Titration system and program

Abstract

The present invention provides a titration system etc. capable of determining an equivalence point with high accuracy and having versatility. The titration system includes a camera installed so as to be able to photograph a flask containing a sample liquid, an image generating unit that generates image data representing an image of the sample liquid based on an image signal output from the camera, a storage unit that stores a plurality of parameter sets including a type of color value to be determined when determining the equivalence point and a judgment criterion corresponding to the type of color value, an operation input unit, a setting unit that reads out from the storage unit a parameter set corresponding to an input signal received by the operation input unit from the plurality of parameter sets and sets the type of color value to be determined and the judgment criterion based on the parameter set, a pixel value acquiring unit that acquires pixel values ​​in an area in the image where the sample liquid is captured, a color value acquiring unit that acquires color values ​​based on the pixel values ​​acquired by the pixel value acquiring unit, and a judging unit that evaluates the color value based on the judgment criterion.

Description

[Technical field]

[0001] The present invention relates to a titration system and a program. [Background technology]

[0002] Known titration methods include a method in which a standard solution containing a titration indicator is dropped into a sample solution and the color of the solution is observed (colorimetric method), and a method in which a standard solution is dropped into a sample solution with an electrode placed therein while measuring the potential difference (potentiometric titration method; see, for example, Patent Document 1).An automatic titration device that detects changes in the color development state of an indicator based on image information from a camera has also been proposed (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2010-101724 A [Patent Document 2] Japanese Patent Application Publication No. 6-58882 Summary of the Invention [Problem to be solved by the invention]

[0004] In the visual colorimetric method, not only is the burden on the operator large, but the judgment of the equivalence point may vary depending on the operator. On the other hand, in the potentiometric titration method, the electrodes must be cleaned every time a titration is performed, making the series of operations required for titration complicated.

[0005] In addition, in Patent Document 2, the sample liquid is irradiated with a light source of the same or complementary color as the titration indicator, or a filter of the same or complementary color as the titration indicator is provided on the light source, so that the end point of the titration is detected by a significant change in the brightness of the sample liquid. However, since various types of indicators are used in colorimetric titration, it is difficult to realize a versatile titration system with a configuration in which the light source and filter are changed according to the type of indicator.

[0006] The present invention has been made in consideration of the above, and an object of the present invention is to provide a titration system and program that can determine an equivalence point with high accuracy and that is versatile. [Means for solving the problem]

[0007] In order to solve the above problems, a titration system according to one aspect of the present invention includes a camera installed so as to be able to photograph a flask containing a sample liquid containing a test substance, and configured to photograph the sample liquid and output an image signal; an image generating unit configured to generate image data representing an image of the sample liquid based on the image signal output from the camera; a memory unit configured to store a plurality of parameter sets including a type of color value to be judged when determining an equivalence point according to a combination of a standard solution to which a titration indicator has been added and the test substance, and a judgment criterion according to the type of color value; and an operation input unit configured to receive an input signal according to an operation performed from outside. The apparatus includes a setting unit configured to read out from the memory unit a parameter set corresponding to an input signal received by the operation input unit from among the multiple parameter sets, and set a type of color value to be judged and a judgment criterion based on the parameter set; a pixel value acquisition unit configured to acquire pixel values ​​in an area in which the sample liquid is captured in an image generated by the image generation unit; a color value acquisition unit configured to acquire a color value of the type set by the setting unit based on the pixel values ​​acquired by the pixel value acquisition unit; and a judgment unit configured to evaluate the color value acquired by the color value acquisition unit based on the judgment criterion set by the setting unit.

[0008] In the titration system, the setting section may be configured to set a plurality of types of color values ​​as targets for judgment, and to set a relative relationship between the plurality of types of color values ​​as a judgment criterion.

[0009] In the titration system, the setting section may be configured to set one type of color value as a determination target, and to set a threshold value of the one type of color value as a determination criterion.

[0010] In the titration system, the setting section may be configured to set one type of color value as the determination target, and to set a manner of change in the one type of color value as the determination criterion.

[0011] In the titration system, the setting unit may be further configured to change the type of color value and the judgment criterion that have been set, in response to an input signal received by the operation input unit.

[0012] The titration system may further include an area designation unit configured to designate a specific area within the image as an observation area in response to an input signal received by the operation input unit, and the pixel value acquisition unit may be configured to acquire pixel values ​​in the observation area.

[0013] In the above titration system, the memory unit may be further configured to store a measurement file including pixel values ​​acquired by the pixel value acquisition unit and color values ​​acquired by the color value acquisition unit, and may also be further configured to store a hash value of the measurement file.

[0014] A program according to another aspect of the present invention is a program to be executed by a computer having an operation input unit that receives an input signal corresponding to an operation performed from outside, and a storage unit, the storage unit storing a plurality of parameter sets including a type of color value to be judged when judging an equivalence point according to a combination of a standard solution to which a titration indicator has been added and a test substance, and a judgment criterion corresponding to the type of color value, and an image generating step of generating image data representing an image of the sample liquid based on an image signal output from a camera that is installed so as to be able to photograph a flask containing a sample liquid containing the test substance and is configured to photograph the sample liquid and output an image signal, and The computer is caused to execute the following steps: a setting step of reading out from the memory unit a parameter set corresponding to the input signal accepted by the operation input unit, and setting the type of color value to be judged and a judgment criterion based on the parameter set; a pixel value acquisition step of acquiring pixel values ​​in an area in which the sample liquid is captured in the image generated in the image generation step; a color value acquisition step of acquiring a color value of the type set in the setting step based on the pixel values ​​acquired in the pixel value acquisition step; and a judgment step of evaluating the color value acquired in the color value acquisition step based on the judgment criterion set in the setting step. Effect of the Invention

[0015] According to the present invention, it is possible to realize a versatile titration system that can determine the equivalence point with high accuracy. [Brief description of the drawings]

[0016] [Figure 1] FIG. 1 is a schematic diagram showing the appearance of a titration system according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram showing the external appearance of the device main body shown in FIG. [Diagram 3] FIG. 1 is a block diagram showing a schematic configuration of a titration system according to an embodiment of the present invention. [Figure 4]FIG. 13 is a schematic diagram illustrating information stored in a titration method file. [Diagram 5] 4 is a flowchart illustrating the operation of a titration system according to an embodiment of the present invention. [Figure 6] FIG. 2 is a schematic diagram illustrating a camera observation screen. [Figure 7] FIG. 13 is a schematic diagram illustrating a method selection screen. [Figure 8] 13 is a schematic diagram illustrating a measurement file creation screen. FIG. [Figure 9] FIG. 13 is a schematic diagram illustrating a method confirmation screen. [Figure 10] 7 is a flowchart showing the titration process of FIG. 6. [Figure 11] FIG. 13 is a schematic diagram illustrating a titration screen. [Figure 12] FIG. 13 is a schematic diagram illustrating a titration screen. [Figure 13] FIG. 13 is a schematic diagram illustrating a titration screen. [Figure 14] FIG. 13 is a schematic diagram illustrating a measurement file selection screen. [Figure 15] FIG. 13 is a schematic diagram illustrating a titration analysis screen. [Figure 16] FIG. 13 is a schematic diagram illustrating a graph / image display screen. [Figure 17] FIG. 13 is a schematic diagram illustrating a method editing screen. [Figure 18] 1 is a graph showing measurement data (CMYK color space) in a verification experiment. [Figure 19] 1 is a graph showing measurement data (CMY color space) in a verification experiment. [Figure 20] 1 is a graph (RGB color space) showing measurement data in a verification experiment. [Figure 21] 1 is a graph showing measurement data (HSV color space) in a verification experiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, a titration system and a program according to an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to these embodiments. In addition, in the description of each drawing, the same parts are indicated by the same reference numerals.

[0018] The drawings referred to in the following description merely show the shape, size, and positional relationship in a schematic manner to the extent that the contents of the present invention can be understood. In other words, the present invention is not limited to the shape, size, and positional relationship exemplified in each drawing. In addition, there may be cases where the dimensional relationship and ratio of each part differs between the drawings.

[0019] <Titration system configuration> Fig. 1 is a schematic diagram showing the appearance of a titration system according to an embodiment of the present invention. The titration system 1 shown in Fig. 1 is a system for detecting a color change in a sample solution 4a containing a test substance caused by dropping a standard solution 5a to which a titration indicator (hereinafter, also simply referred to as an indicator solution) has been added into the sample solution 4a, and includes an apparatus main body 2 and an information processing device 3 connected to the apparatus main body 2 so as to be capable of wired or wireless communication.

[0020] Fig. 2 is a schematic diagram showing the appearance of the device main body 2. As shown in Fig. 2, the device main body 2 has a built-in camera 10 and a light source 20. The camera 10 is installed so as to be able to capture an image of the flask 4 containing the sample liquid 4a. The light source 20 is, for example, a white surface-emitting LED light, and illuminates the flask 4. In this embodiment, the light source 20 is installed so as to illuminate the flask 4 from above the camera 10 at an oblique angle.

[0021] The device main body 2 is provided with a stage mounting section 2a on which a stage 7 for placing a flask 4 is installed. By installing the stage 7 of a predetermined height on this stage mounting section 2a and placing the flask 4 on the stage 7, at least a portion of the flask 4 can be captured within the field of view of the camera 10.

[0022] A stage with a built-in stirrer (magnetic stirrer) may be used as the stage 7. By inserting a stirrer into the flask 4 and operating the stirrer, the sample solution 4a and the standard solution 5a in the flask can be stirred to cause a quick and uniform reaction. In addition, a support part 6 for holding an electric burette 5 above the flask 4 may be provided on the stage installation part 2a or the stage 7.

[0023] The electric burette 5 drips the standard solution 5a under the control of the information processing device 3. Of course, instead of the electric burette 5, a manual burette may be used.

[0024] The device body 2 is provided with a groove-shaped back plate installation portion 2b into which the back plate 8 is fitted. By arranging the back plate 8 on the opposite side of the flask 4 from the camera 10 and the light source 20, it is possible to prevent external light from entering the camera 10. It should be noted that the camera 10 and the light source 20 do not need to be built into the device body 2, and these devices may be installed separately.

[0025] Fig. 3 is a block diagram showing a schematic configuration of the titration system 1. As shown in Fig. 3, the titration system 1 includes a camera 10 configured to capture an image of the sample liquid 4a and output an image signal, and an information processing device 3 configured to capture the image signal output from the camera 10 and execute various processes to determine the equivalence point in titration.

[0026] The camera 10 is an imaging device that has an imaging element such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal Oxide Semiconductor) and is capable of capturing moving images at a predetermined frame rate. The imaging element receives light (subject image) that is incident on the camera 10 and focused by an optical system on a light receiving surface, and generates an electrical signal by performing photoelectric conversion. The camera 10 generates and outputs an image signal by performing predetermined signal processing such as amplification and A / D conversion on the electrical signal.

[0027] The information processing device 3 includes an external interface (I / F) 110, a storage unit 120, and a calculation unit 130. The information processing device 3 may also include a display unit 30 and an operation input unit 40.

[0028] The display unit 30 is, for example, a display device such as a liquid crystal display, an organic EL display, etc. The operation input unit 40 is, for example, an input device such as a keyboard, a mouse, a touch panel, an input button, etc., and inputs a signal according to an operation performed by a user to the calculation unit 130.

[0029] The external interface 110 is an interface for inputting and outputting various signals, such as outputting control signals and inputting image signals, between external devices, such as the camera 10 and the electric burette 5, connected to the information processing device 3. The external interface 110 can adopt various communication standards, such as USB (Universal Serial Bus), Bluetooth (registered trademark), WiFi (Wireless Fidelity), and others.

[0030] The storage unit 120 is configured using a computer-readable storage medium such as a semiconductor memory such as a ROM or a RAM, or a disk drive. The storage unit 120 stores an operating system program, a driver program, a program for causing the calculation unit 130 to execute a predetermined operation, and various data and parameters used during execution of the program. In detail, the storage unit 120 includes a program storage unit 121 that stores a titration program for determining an equivalence point based on an image captured by the camera 10, a parameter storage unit 122 that stores a plurality of parameter sets used in determining the equivalence point, a measurement file storage unit 123 that stores a measurement file created for each titration process performed in the titration system 1, and a user information storage unit 124.

[0031] The parameter storage unit 122 stores a plurality of titration method files created for each titration method. The titration method file is a file that stores parameters when the titration system 1 executes a titration process, and is created for each titration method, such as a base titration method using phenolphthalein (PP) and an acid titration method using methyl orange (MO). The parameter storage unit 122 stores a plurality of titration method files related to basic titration methods in advance as initial settings.

[0032] 4 is a schematic diagram illustrating information stored in a titration method file. Each titration method file stores the method title, titration target (sample solution), standard solution, indicator solution, initial addition amount, maximum drip amount, drip amount per drip, drip interval, drip end condition, judgment condition, etc. Among these, the judgment condition includes the type of color value to be judged when judging the equivalence point according to the combination of the standard solution to which the titration indicator has been added and the test substance, and the judgment criterion according to the type of color value.

[0033] In detail, when the object to be judged is one type of color value, the judgment criterion may include a threshold value for the color value and a condition for the threshold value (above threshold value, below threshold value, etc.). When the object to be judged is one type of color value, the judgment criterion may set a manner of change of the color value. For example, judgment criteria such as a sudden change in the first derivative (rate of change) of the color value, a change in the sign of the first derivative, or a change in the sign of the second derivative are exemplified. Alternatively, when the object to be judged is multiple types of color values, the judgment criterion may include a relative relationship between these color values ​​(for example, a magnitude relationship between two types of color values, a ratio, a change in ratio, etc.). Furthermore, the judgment criterion may include a value (hereinafter referred to as a selected value) used for judgment among the color values ​​obtained by measurement. For example, a measurement value for each measurement, a moving average of multiple measurement values, etc. are exemplified.

[0034] Specifically, color values ​​that can be used in determining the equivalent point in this embodiment include the R value, G value, and B value in the RGB color space, the C value in the CMYK color space, the M value in the CMYK color space, the Y value, K value in the CMYK color space, the C value, M value, and Y value in the CMY color space, the H value, S value, and V value in the HSV color space, and the H value, L value, and S value in the HLS color space. When using these color values, the equivalent point can be determined by comparing them with a preset threshold value.

[0035] Furthermore, combinations of multiple types of color values ​​that can be used to determine the equivalent point include combinations of C and M values, C and Y values, C and K values, M and Y values, M and K values, and Y and K values ​​in the CMYK color space. When using these combinations, the equivalent point can be determined based on the relative relationship between the two types of color values.

[0036] Typical examples of the types of color values ​​to be judged and the judgment criteria are stored in a titration method file pre-stored in the titration system 1. The user can change the types of color values ​​and the judgment criteria to any desired ones. In other words, the user can create a desired titration method by making any desired changes to various items, including the types of color values ​​and the judgment criteria, of the pre-stored titration method file and saving it under a file name.

[0037] The measurement file stored in the measurement file storage unit 123 stores file information including the titration title, the lot number of the sample to be titrated, the sample number, the saved file name, etc., the titration method used in the titration process, image data of the image of the standard solution captured by the camera 10, and measurement data including pixel values ​​in the observation area in the image and color values ​​converted from the pixel values. As the measurement data, color values ​​in all color spaces set in the information processing device 3 may be stored, or only color values ​​in some color spaces may be stored. In the former case, there is an advantage that the processing can be accelerated when the measurement file is read out and color values ​​in a user-desired color space are to be displayed.

[0038] The user information storage unit 124 stores information (user information) about a user who uses the information processing device 3. The user information includes login information such as a user account and a password, a name, an affiliation, an email address, and an access right to data.

[0039] The calculation unit 130 is configured using hardware such as a CPU (Central Processing Unit) or a GPU (Graphics Processing Unit), and transfers data and issues instructions to each unit of the information processing device 3 by reading and executing various programs stored in the program storage unit 121, thereby controlling the overall operation of the information processing device 3. The calculation unit 130 also reads a titration program to execute a series of titration processes for determining an equivalent point based on an image captured by the camera 10. Functional units realized by the calculation unit 130 reading the titration program include an imaging control unit 131, a drip control unit 132, a display control unit 133, a setting unit 134, an image generation unit 135, an area designation unit 136, a pixel value acquisition unit 137, a color value acquisition unit 138, a determination unit 139, a data management unit 140, and a user information management unit 141.

[0040] The shooting control unit 131 controls the start and end of shooting by the camera 10, and also controls the operation of the camera 10 so as to perform shooting at a predetermined shooting frame rate.

[0041] The drip control unit 132 controls the operation of the electric burette 5. In detail, the drip control unit 132 controls the start and end of dripping in the electric burette 5, the amount of dripping per drip, the drip interval, and the like. The display control unit 133 causes the display unit 30 to display a predetermined titration screen.

[0042] The setting unit 134 selects a titration method corresponding to an input signal received by the operation input unit 40 from among the multiple titration methods, and reads out a titration method file (parameter set) of the selected titration method from the parameter storage unit 122. Then, the setting unit 134 initializes judgment conditions for judging the equivalence point based on the information stored in the titration method file. Furthermore, the setting unit 134 changes the initially set judgment conditions to judgment conditions designated by the user in response to an input signal received by the operation input unit 40.

[0043] The image generating section 135 generates image data representing an image of the sample liquid based on the image signal output from the camera 10.

[0044] The area designation unit 136 designates a particular area within the image showing the sample liquid as an observation area in response to an input signal received by the operation input unit 40 .

[0045] The pixel value acquiring section 137 acquires pixel values ​​in a region in which the sample liquid appears in the image generated by the image generating section 135. That is, the pixel value acquiring section 137 acquires pixel values ​​in an observation region in the image.

[0046] The color value acquisition unit 138 acquires a color value of the type set by the setting unit 134 based on the pixel value acquired by the pixel value acquisition unit 137. In detail, the color value acquisition unit 138 acquires an R value, a G value, and a B value from image data related to the observation area, and calculates a color value using these R value, G value, and B value and a predetermined arithmetic expression.

[0047] The judgment unit 139 evaluates the color value acquired by the color value acquisition unit 138 based on the judgment conditions set by the setting unit 134. Then, when the color value satisfies the judgment criterion, it is judged that the equivalence point has been reached.

[0048] The data management unit 140 manages various data stored in the measurement file storage unit 123. For example, the data management unit 140 executes processes such as creating a measurement file and storing it in the measurement file storage unit 123 every time a titration process is performed, and searching for and reading out the measurement file stored in the measurement file storage unit 123 in response to an operation on the operation input unit 40.

[0049] Here, when saving a new measurement file, the data management unit 140 may store a hash value obtained by hashing the original measurement file in the measurement file storage unit 123 in addition to the original measurement file. In this case, when reading and displaying a saved measurement file, the data management unit 140 may hash the measurement file to be read and compare the hash value with the hash value of the original measurement file. As a result, even if the measurement file has been tampered with, it is possible to identify the fact that the measurement file has been tampered with and the tampered part by comparing the hash value of the measurement file after tampering with the hash value of the original measurement file.

[0050] The user information management unit 141 manages the user information stored in the user information storage unit 124 based on information input from the operation input unit 40, and also performs operations such as password encryption, user authentication, and management of access rights to data.

[0051] As for the password, the user information management unit 141 may store only the hash value obtained by hashing the password in the user information storage unit 124. In this case, even if the login information is leaked from the information processing device 3, the original password cannot be restored from the hash value, so that it is possible to prevent unauthorized access to the information processing device 3 by a third party. Furthermore, when hashing the password, the user information management unit 141 may use a salt (an arbitrary character string that is assigned to the password before hashing) and a pepper (a fixed character string that is assigned to the password before hashing). In this case, the data management unit 140 may store the pepper in a different layer from the user information, or may store the pepper in another storage device that is connected to the information processing device 3 by wired or wireless communication.

[0052] <Titration system operation> First, the information processing device 3 requests the accessing user to input a user account and password, and performs authentication. If the authentication is successful, the titration system 1 starts the following operations related to titration.

[0053] FIG. 5 is a flowchart showing the operation of a titration system according to an embodiment of the present invention. First, the titration system 1 causes the camera 10 to start capturing images (step S10). As a result, an image is generated in the information processing device 3 based on image signals sequentially output from the camera 10.

[0054] FIG. 6 is a schematic diagram illustrating a camera observation screen displayed on the display unit 30 when the camera 10 starts shooting. The camera observation screen A1 includes an image display area a11 in which an image captured by the camera 10 is displayed, a frame a12 displayed in the image, a size display area a13 showing the size of the frame a12, a pixel value display area a14 in which pixel values ​​(R value, G value, B value in RGB color space) in the frame a12 are displayed, a color value display area a15 in which values ​​obtained by converting the pixel values ​​into color values ​​in various color spaces (CMYK color space, CMY color space, HSV color space, HLS color space), an update button a16, and an end button a17. As the pixel values, statistical values ​​such as the average value or median value of the pixel values ​​of the pixels located in the frame a12 may be displayed. The user can change the position and size of the frame a12 in the image display area a11 using the operation input unit 40.

[0055] Next, the titration system 1 specifies an observation area (step S11). Here, when an operation of pressing the update button a16 (e.g., a click operation or a tap operation; the same applies below) is performed, the titration system 1 updates the values ​​in the pixel value display area a14 and the color value display area a15. The user can adjust the position and size of the frame a12 while checking the updated values. Furthermore, when the end button a17 is pressed, the titration system 1 specifies the area surrounded by the frame a12 as the observation area in a series of titration processes.

[0056] Next, the titration system 1 sets parameters (step S12). FIG. 7 is a schematic diagram illustrating a method selection screen displayed on the display unit 30 when parameters are set. The method selection screen A2 includes a method selection area a21, a method detailed information display area a23, and an OK button a24. The method selection area a21 displays the titles of multiple titration method files stored in the parameter storage unit 122. The method detailed information display area a23 displays information about the method on which the cursor a22 is placed in the method selection area a21, that is, information about the name of the selected titration method, the titration target, the standard solution, the indicator solution, and the like. When the OK button a24 is pressed, the titration system 1 reads out a titration method file (parameter set) corresponding to the selected titration method from the storage unit 120 and performs initial parameter settings. In the following, it is assumed that the parameters in the basic titration method (PP) shown in FIG. 4 are set as an example.

[0057] Next, the titration system 1 creates a measurement file (step S13). FIG. 8 is a schematic diagram illustrating a measurement file creation screen. The measurement file creation screen A3 is provided with a titration method display field a31, a file information input field a32 including a titration title, a lot number of the sample to be titrated, a sample number, a saved file name, and the like, a file name display area a33 in which an existing file name is displayed, and an OK button a34. The titration title is a name that represents the titration process to be executed this time, and can be arbitrarily determined by the user. The user can create a new measurement file by arbitrarily inputting necessary information in the file information input field a32. In addition, by placing the cursor on any of the file names displayed in the file name display area a33, the file information of the file is reflected in the file information input field a32, and the user may create a new file by arbitrarily modifying the information displayed in the input field a32. When the OK button a34 is pressed with necessary information entered in the file information input field a32, the titration system 1 creates a new measurement file related to the titration method displayed in the titration method display field a31.

[0058] Next, the titration system 1 executes titration (step S14). FIG. 9 is a schematic diagram illustrating a method confirmation screen. The method confirmation screen A4 has a display area a41 for a titration method and a titration title, a display area a42 for a confirmation message, and an OK button a43. When the OK button a43 is pressed, the titration system 1 starts the titration process. If a stirrer is built into the stage 7 on which the flask 4 is placed, the stirrer may be started at this time. The stirrer may be started under the control of the titration system 1, or may be started by the user manually turning on a switch.

[0059] Fig. 10 is a flow chart showing the titration process of Fig. 5. The titration system 1 first controls the electric burette 5 based on the initial addition amount stored in the titration method file to initially add the standard solution (step S140). If the initial addition amount is not set, step S140 may be omitted.

[0060] FIG. 11 is a schematic diagram illustrating a titration screen displayed on the display unit 30 during initial addition. The titration screen A5 includes a display area a50 for file information of the measurement file, a parameter display area a51 for displaying parameters set based on the titration method file, a titration status display area a52 for displaying the amount of standard solution dropped and the elapsed titration time, a color value display area a53 ​​for displaying the current value of the color value used to determine the equivalence point, a color space selection area a54 for displaying a graph, a color value graph display area a55, an image display area a56, a start button a57, an end button a58, and a comment area a59. The graph display area a55 displays a graph of each color value in a color space (e.g., CMYK color space) including the initially set color value. The user can operate the color space selection area a54 to display color values ​​in other color spaces (e.g., RGB color space, CMYK color space, CMY color space, HSV color space, HLS color space) in the graph display area a55.

[0061] When the start button a57 is pressed after the initial addition is completed, the titration system 1 starts dripping the standard solution (step S141). FIG. 12 is a schematic diagram illustrating a titration screen displayed on the display unit 30 after the start of dripping of the standard solution. A pause button a60 is displayed on the titration screen A5 after the start of dripping. The user can interrupt the titration by pressing the pause button a60 as necessary. In addition, the user can force-terminate the titration by pressing the end button a58. Furthermore, the user can write a comment at any time in the comment area a59.

[0062] The titration system 1 acquires pixel values ​​in the observation area in synchronization with the dropping interval of the standard solution (step S142). In detail, the titration system 1 acquires pixel values ​​(R value, B value, G value) of pixels constituting a specified observation area (see step S11) in the image, and calculates statistics such as the average value and median value of these pixel values.

[0063] Next, the titration system 1 acquires color values ​​used to determine the equivalence point based on the acquired pixel values ​​(step S143). For example, when the M value in the CMYK color space is used to determine the equivalence point, the titration system 1 calculates the M value using the R value, G value, and B value acquired in step S142 and a predetermined conversion formula.

[0064] Next, the titration system 1 judges whether the acquired color value satisfies the judgment criteria (step S144). For example, if the judgment criteria are set to "threshold: 0.1, selection value: moving average (5 points), condition: below threshold", the titration system 1 calculates the average value of the color values ​​acquired for the four drops before this drip and the color value acquired this time, and judges whether this average value is below the threshold value of 0.1.

[0065] If the color value does not satisfy the judgment criterion (step S145: No), the process returns to step S142. On the other hand, if the color value satisfies the judgment criterion (i.e., if the equivalence point is reached, step S145: Yes), the titration system 1 ends the dripping of the standard solution (step S146), and then the process returns to the main routine. FIG. 13 is a schematic diagram illustrating a titration screen displayed on the display unit 30 at the end of dripping of the standard solution. The start button a57 is displayed again on the titration screen A5 shown in FIG. 13. Note that the titration system 1 stops dripping of the standard solution at the stage where it is determined that the color value satisfies the judgment criterion, but may start dripping again when the start button a57 is pressed. That is, dripping can be resumed at the discretion of the user. In addition, if a specific dripping end condition is set in the titration method file, the titration system 1 controls the end of dripping according to the dripping end condition.

[0066] 5 again, after the titration is completed, the titration system 1 saves the titration result (step S15). In detail, the color value data in each space acquired each time the standard solution is dropped from the start of dropping to the end of dropping is stored in a measurement file together with the image data, and is stored in the measurement file storage unit 123. At this time, a hash value obtained by hashing the measurement file may also be stored in the measurement file storage unit 123. Thereafter, the titration process in the titration system 1 is completed.

[0067] <Analysis of titration results> In the titration system 1, the user can also use the saved measurement file to analyze the titration result afterwards. Fig. 14 is a schematic diagram illustrating a measurement file selection screen. The file selection screen A6 has a search item selection area a61, a display area a62 of the titration title extracted by the search, a data selection area a63, a detailed information display area a64, and an OK button a65.

[0068] Measurement files can be searched not only by titration title, but also by titration method, user name (operator), operation date, lot number, sample number, and comment. In the data selection area a63, a list of measurement file names related to the titration title where the cursor a66 is placed in the display area a62 is displayed. In the detailed information display area a64, detailed information related to the measurement file where the cursor a67 is placed in the data selection area a63 is displayed. When the OK button a65 is pressed with the measurement file name selected in the data selection area a63, the titration system 1 reads out the selected measurement file from the measurement file storage unit 123 and displays it on the display unit 30.

[0069] At this time, the titration system 1 may hash the selected measurement file and compare the hash value with the hash value of the original measurement file stored in the measurement file storage unit 123. If a difference is found between the two hash values ​​as a result, the titration system 1 may display a warning on the display unit 30 to the effect that the measurement file may have been tampered with.

[0070] 15 is a schematic diagram illustrating a titration analysis screen. The titration analysis screen A7 includes a detailed information display area a71 in which the titration method, file name, various parameters, etc. in the measurement file read from the measurement file storage unit 123 are displayed, a measurement data display area a72, a graph / image display button a73, a reanalysis button a74, an analysis method selection area a75, and a save button a76. In addition to the pixel values ​​acquired during the titration process and the color values ​​set as the judgment conditions, various color values ​​that can be acquired in the titration system 1 may be displayed in the measurement data display area a72.

[0071] In the analysis method selection area a75, the color value, threshold value, selection value, and conditions for judging the equivalence point can be selected by the user's operation. When the analysis method selection area a75 is operated and the reanalysis button a74 is pressed, the titration system 1 reanalyzes the equivalence point with the changed judgment conditions. In addition, when the save button a76 is pressed, the titration system 1 saves a new file including the changed contents.

[0072] Furthermore, when the graph / image display button a73 is pressed, the titration system 1 displays a graph / image display screen A8, as shown in Fig. 16, on the display unit 30. The graph / image display screen A8 is provided with an image display area a80 in which an image captured by the camera 10 is displayed, a graph display area a81 in which a graph of color values ​​is displayed, a color value selection area a82, and a graph update button a83.

[0073] The user can select the type of color value used to determine the equivalence point by checking the check boxes of color values ​​in various color spaces displayed in the color value selection area a82. When the graph update button a83 is pressed with any check box checked, the titration system 1 displays a graph of the checked color values ​​in the graph display area a81.

[0074] A frame a84 representing the observation area is displayed in the image display area a80. The user can change the position and size of this frame a84 using the operation input unit 40. When the frame a84 is changed, the titration system 1 may obtain the pixel values ​​of each pixel in the changed frame a84 and recalculate the color values ​​in the measurement data display area a72 (see FIG. 15).

[0075] <Editing titration method> In the titration system 1, a user can create a new titration method by editing an existing titration method. Fig. 17 is a schematic diagram illustrating a method editing screen. The method editing screen A9 is provided with a method name input field a91, a method editing area a92, an analysis method editing area a93, and a Save New button a94.

[0076] When the name of a titration method is input in the method name input field a91, the titration system 1 reads out the corresponding titration method file from the parameter storage unit 122, and displays the parameters of the titration target (sample solution), standard solution, indicator solution, maximum drop amount, initial addition amount, titration end setting, drop amount per drop, drop interval, etc. in the method editing area a92, and also displays the equivalence point judgment conditions (color value type, selection value, threshold value, condition) in the analysis method editing area a93. The user can change the contents displayed in the method editing area a92 and the analysis method editing area a93. The means for changing the contents may be a method of selecting the desired contents from a drop-down list provided for each item, or a method of inputting any contents as text. When the new save button a94 is pressed, the titration system 1 creates a new titration method file that stores the contents of the edited titration method, and stores it in the parameter storage unit 122. As a result, the file name of the newly created titration method file is displayed on the method selection screen A2 illustrated in FIG. 7.

[0077] As described above, according to this embodiment, the equivalence point can be determined by an appropriate color value and judgment criterion depending on the combination of the test substance and the standard solution to which the titration indicator has been added, and it becomes possible to perform a titration with high accuracy. In addition, since a plurality of parameter sets are stored in advance in the storage unit depending on the combination of the test substance and the standard solution to which the titration indicator has been added, it becomes possible to realize a versatile titration system.

[0078] Furthermore, according to this embodiment, in each titration method, appropriate color values ​​and judgment criteria for determining the equivalence point are pre-initialized according to the combination of the standard solution to which the titration indicator has been added and the test substance, so that even a user who is unfamiliar with titration can easily and accurately determine the equivalence point.

[0079] In addition, according to this embodiment, the user can change the initially set type of color value and judgment criteria by operating the operation input unit, so that the equivalent point can be judged based on the desired type and judgment of color value.

[0080] Furthermore, according to this embodiment, a specific area within an image can be designated as the observation area in accordance with an input signal received by the operation input unit, thereby enabling the user to set an appropriate observation area at their discretion.

[0081] Furthermore, according to this embodiment, in addition to the original measurement file storing the titration measurement data, a hash value of the measurement file is stored, so that if the original measurement file is tampered with, it is possible to identify this fact and the part that has been tampered with.

[0082] (Verification experiment) A titration test for measuring the amino acid content of sake was carried out using the titration system 1 according to this embodiment. The measurement method followed the National Research Institute of Brewing's standard analysis method 3-6 Amino Acid B) Measurement of Amino Acid Content by Ethanol Addition Method (reference: https: / / www.nta.go.jp / taxes / sake / sonota / sokuteihoho / pdf / 10.pdf).

[0083] Here, the measurement of the amino acid content by the ethanol addition method is carried out as follows. Sample solution: Sake (seishu) Indicator: Phenolphthalein indicator (0.5 g of phenolphthalein dissolved in 50 mL of ethanol) Standard solution: 0.1 mol / L (N / 10) sodium hydroxide solution Ethanol: Ethanol (99.5) (special grade) (based on JIS K8101:2006)

[0084] Step 1: Add a few drops of phenolphthalein indicator to 10 mL of sample. Step 2: Neutralize the solution from step 1 by adding N / 10 sodium hydroxide solution until a pale pink color appears. Step 3: Add 25 mL of ethanol to the solution in step 2 to return it to colorless. Step 4: Add N / 10 sodium hydroxide solution to the solution in step 3 until it turns pale pink again, then titrate. Then, determine the titration value "a" at the end point. Step 5: Using the titer F, calculate the amino acid degree by a x F (rounded off to two decimal places).

[0085] In the above step 4, 50 μL of the standard solution (N / 10 sodium hydroxide solution) was added. Then, while obtaining measurement data by the titration system 1, the end point was visually determined. The titration amount at the end point determined by visual observation was 1.05 mL. The change in color value in various color spaces relative to this titration amount was verified.

[0086] Figures 18 to 21 are graphs showing measurement data from the verification experiment. In Figures 18 to 21, the horizontal axis shows the amount of standard liquid dropped after the addition of ethanol (step 3). As for the vertical axis, Figure 18 shows color values ​​in the CMYK color space, Figure 19 shows color values ​​in the CMY color space, Figure 20 shows color values ​​in the RGB color space, and Figure 21 shows color values ​​in the HSV color space.

[0087] In the case of the CMYK color space (see Figure 18), no significant change was observed in the color values ​​even when the end point (1.05 μL) was reached. This is thought to be because in this experiment, the standard liquid became cloudy when it was dropped, causing the color values ​​to change slowly. In contrast, in the case of the CMY color space (see Figure 19), a steep change was observed in the M value near the end point. The M value at the end point was 0.525.

[0088] In the RGB color space (see Figure 20), the R, G, and B values ​​all tended to decrease before the end point was reached, but the R value began to increase when the end point was reached. On the other hand, in the HSV color space (see Figure 21), there were no significant changes in the H, S, or V values ​​when the end point was reached, and the H value suddenly decreased when the next drop after the end point (1.05 μL) was dispensed.

[0089] From the above experimental results, it was found that it is appropriate to judge the end point in the CMY color space when measuring the amino acid content by the ethanol addition method. That is, in the CMY color space, the M value becomes steep near the end point, so by setting a threshold value for the M value (e.g., 0.525), it is possible to clearly judge whether the threshold value has been exceeded each time the standard solution is dropped.

[0090] The present invention is not limited to the above-described embodiment and modified examples, and may be embodied in various other forms without departing from the scope of the present invention. For example, some components may be removed from all the components shown in the embodiment and modified examples, or the components shown in the above embodiment and modified examples may be appropriately combined. [Explanation of symbols]

[0091] 1...titration system, 2...apparatus body, 2a...stage installation section, 2b...back panel installation section, 3...information processing device, 4...flask, 4a...sample liquid, 5...motorized burette, 5a...standard liquid, 6...support section, 7...stage, 8...back panel, 10...camera, 20...light source, 30...display section, 40...operation input section, 110...external interface, 120...storage section, 121...program storage section, 122...parameter storage section, 123...measurement file storage section, 124...user information storage section, 130...calculation section, 131...photography control section, 132...dropping control section, 133...display control section, 134...setting section, 135...image generation section, 136...area designation section, 137...pixel value acquisition section, 138...color value acquisition section, 139...determination section, 140...data management section, 141...user information management section

Claims

1. a camera that is installed so as to be able to photograph a flask containing a sample liquid containing a test substance and is configured to photograph the sample liquid and output an image signal; an image generating unit configured to generate image data representing an image of the sample liquid based on an image signal output from the camera; A storage unit configured to store a plurality of parameter sets including a type of color value to be determined when determining the equivalence point according to a combination of a standard solution to which a titration indicator has been added and a test substance, and a determination criterion according to the type of color value; An operation input unit configured to receive an input signal corresponding to an operation performed from outside; a setting unit configured to read out from the storage unit a parameter set corresponding to an input signal received by the operation input unit from among the plurality of parameter sets, and to set a type of color value to be determined and a determination criterion based on the parameter set; a pixel value acquiring unit configured to acquire pixel values ​​in an area in which the sample liquid is captured within the image generated by the image generating unit; a color value acquisition unit configured to acquire a color value of the type set by the setting unit based on the pixel value acquired by the pixel value acquisition unit; a determination unit configured to evaluate the color value acquired by the color value acquisition unit based on the determination criterion set by the setting unit; A titration system comprising:

2. The titration system according to claim 1 , wherein the setting unit is configured to set a plurality of types of color values ​​as targets for judgment, and to set a relative relationship between the plurality of types of color values ​​as a judgment criterion.

3. The titration system according to claim 1 , wherein the setting unit is configured to set one type of color value as a determination target and to set a threshold value of the one type of color value as a determination criterion.

4. The titration system according to claim 1 , wherein the setting unit is configured to set one type of color value as the determination target, and to set a manner of change in the one type of color value as the determination criterion.

5. The titration system according to any one of claims 1 to 4, wherein the setting unit is further configured to change the type and judgment criteria of the set color value in response to an input signal accepted by the operation input unit.

6. a region designation unit configured to designate a specific region in the image as an observation region in response to an input signal received by the operation input unit, The titration system according to any one of claims 1 to 4, wherein the pixel value acquisition unit is configured to acquire pixel values ​​in the observation region.

7. The titration system according to any one of claims 1 to 4, wherein the memory unit is further configured to store a measurement file including pixel values ​​acquired by the pixel value acquisition unit and color values ​​acquired by the color value acquisition unit, and is further configured to store a hash value of the measurement file.

8. A program to be executed by a computer having an operation input unit that receives an input signal corresponding to an operation performed from outside and a storage unit, The memory unit stores a plurality of parameter sets including a type of color value to be determined when determining the equivalence point according to a combination of a standard solution to which a titration indicator has been added and a test substance, and a determination criterion according to the type of color value; an image generating step of generating image data representing an image of the sample liquid based on an image signal output from a camera that is installed so as to be able to capture an image of a flask containing a sample liquid containing a test substance and that is configured to capture an image of the sample liquid and output an image signal; a setting step of reading out from the storage unit a parameter set corresponding to an input signal received by the operation input unit from among the plurality of parameter sets, and setting a type of color value to be judged and a judgment criterion based on the parameter set; a pixel value acquiring step of acquiring pixel values ​​in a region in which the sample liquid is captured in the image generated in the image generating step; a color value acquiring step of acquiring a color value of the type set in the setting step based on the pixel value acquired in the pixel value acquiring step; a determination step of evaluating the color value acquired in the color value acquisition step based on the determination criterion set in the setting step; A program for causing the computer to execute the above.

Images