242 results about "Force analysis" patented technology

The invention discloses a control system for measuring the energy consumption of urban rail transit and an evaluation method. The control system comprises a vehicle-mounted energy consumption control unit, a data management unit and a ground energy consumption control unit. The control system has the beneficial effects that the system is a multi-path sampling energyconsumption metering system; drive control is carried out by adopting a permanent-magnet synchronous DC motor; a double-energy control module is built by using a super capacitor and a lithium battery for vehicle-mounted energy conversion control; train force analysis and modeling are not needed; a large quantity of nonlinear analysis or intelligent optimization calculation is not needed; traction energy consumption, regenerative braking energy and auxiliary energy consumption can be measured and monitored by directly utilizing collected voltage and current data; the control system has the functions of real-time storage and display of energy consumption data; the energy consumption data can be uploaded to the ground energy consumption control unit through the data management unit; the labor cost is reduced; the control system has a fault detection function; and the fault can be accurately reported when the system fails.

The invention discloses a high-speed axisymmetric aircraft composite control method. The high-speed axisymmetric aircraft composite control method is used for solving the technical problem of poor stability in an existing interceptor missile direct force and aerodynamic force composite control method. According to the technical scheme, a varying centroid and pneumatic rudder composite control are adopted, based on defining a varying centroid control mode, an instruct allocation strategy under a composite control scheme is formulated; a dynamical model for control is established through force analysis of a high-speed aircraft; an overall scheme of a varying centroid mechanism is further determined; then ballistic characteristic points are taken to finish design of a control system. According to the high-speed axisymmetric aircraft composite control method, the varying centroid mechanism is introduced, so that the technical problem of poor stability of a background technology control method is effectively avoided, larger control torque is obtained while energy consumption is reduced as much as possible, and reentry flight of the high-speed aircraft for a long time in a large airspace is facilitated; a composite mode with the pneumatic rudder is adopted, so that work pattern of a sliding block executing mechanism is simplified, and system stability is improved.

The invention provides a megawatt wind power generation adjustable blade bearing friction moment numerical control testing machine and a testing method. The tested bearing outer ring is fixed on the machine rack; a main axis is equipped, one end of the bearing inner ring is fixed on the bearing inner ring, the other end is equipped with a radial and axial loading mechanism, in which the radial and axial load cylinder are separately pressured, and is equipped with variable-frequency motor of torque sensor, the driving pinion is meshed with the tested bearing inner ring, which form the loading and transmission system. The testing machine is determined by force analysis and analog loading principle, which is reasonable and reliable, and has simple structure and small size. The closed-loop numerical control system, which is composed of an industrial computer, a hydraulic pressure control member, a hydro cylinder, a feedback element and other components, can realize overall monitor, data collection, analysis, process, and number and graph double output; the size, direction, variation period of the load are accurate, the curves of the load output and friction torque are intuitive, the testing process is highly automatic. And the invention can be matched with manual adjustment. The machine is shutdown automatically if any failure happens. The test provides data support for the bearing wind turbines, which assures that the machine can meet the test need after loading.

The invention discloses a soft rock tunnel deformation control method based on anchor rod force analysis. A soft rock tunnel is excavated and subjected to deformation control construction from back to front according to multiple segments, and when any segment is excavated and subjected to deformation control construction, the method includes the steps that 1, surrounding rock basic mechanical parameters are determined; 2, the tunnel reserved excavated volume is determined; 3, the tunnel is excavated; 4, a tunnel preliminary bracing structure is determined; 5, tunnel deformation control construction is carried out, wherein in the tunnel preliminary bracing construction process, a flexible mold bracing structure is constructed from back to front; 6, a next segment is excavated and subjected to deformation control construction; 7, the step 6 is repeated multiple times till the full excavation and deformation control construction process of the soft rock tunnel is completed. The soft rock tunnel deformation control method is reasonable in design, convenient to achieve and good in use effect, the reserved excavated volume is determined according to the surrounding rock deformation condition of the soft rock tunnel, the flexible mold bracing structure is adopted for carrying out full-section bracing on the tunnel, the flexible mold bracing structure and the tunnel preliminary bracing structure are in coordination deformation, and deformation of the soft rock tunnel can be effectively controlled.

The invention provides a heterogeneous fleet fault tolerance control method based on a variable time interval strategy. The method comprises the following steps of carrying out force analysis on longitudinal motion of vehicles and combining an actuator fault model to establish a vehicle longitudinal dynamics model under an actuator fault; constructing the variable time interval strategy with a lower boundary of fault information according to information of the vehicles; based on the constructed variable time interval strategy, establishing a proportional integral differential sliding mode surface and a coupled sliding mode surface; and selecting an appropriate Lyapunov function to design a fault-tolerant controller and an adaptive update rate, and proving finite time stability of a system.Traffic flow stability is proved based on the variable time interval strategy with the lower boundary of the fault information. Queue stability is proved based on the proportional integral differential sliding mode surface and the coupled sliding mode surface. Compared with a traditional variable time interval strategy, by using the technical scheme of the invention, a problem of a non-zero initial spacing error can be solved, and a critical traffic capacity can be increased.

The invention relates to a method for determining an optimal dangerous sliding surface of a push-type landslide and an optimal pile position of an anti-slide pile, and belongs to the technical field of landslide stability evaluation and prevention. The method comprises the following steps: 1, carrying out pretreatment; performing exploration and determination of basic physical and mechanical parameters of the push type landslide slope body; determining a pushing type landslide slope body, strip block downward sliding force and residual downward sliding force, determining a landslide active sliding area, an extrusion area and a stable area, determining a most dangerous sliding surface formed by a pushing type landslide shear-off opening, determining critical residual downward sliding thrustof a landslide local damage position and determining an optimal landslide anti-sliding pile position. The method has the beneficial effects that according to the ultimate balance condition of the landslide slope body, the striping-is adopted; Sequentially a most dangerous sliding surface formed by the landslide shear-off opening, a landslide local damage shear-off opening mechanical criterion anda compensation residual sliding thrust value of the anti-slide pile are determined by using a residual sliding force analysis method; The optimal anti-slide pile position for push type landslide treatment is determined, and the purpose of scientific and effective treatment of the landslide is achieved.

The invention relates to a force analysis method of a single point buoy mooring system of an extra-large ship under the coupling action of stormy waves and provides a mooring force mathematical model suitable for a single point buoy anti-typhoon mooring system of the extra-large ship, which are used for performing identification modeling on a non-steady motion strained condition under a typhoon environment and performing a mathematical simulation test and actual measurement verification on the force motion of the ship without power and interference effects of the typhoon environment. Required input and output data are provided for the identification modeling of the mathematical model through a ship motion physical model test of a single point mooring ship model under the action of wind, currents and waves; and a mooring curve of a buoy type anti-typhoon single point mooring system is deduced and the influence of all component parts on the mooring curve is analyzed by researching a ship-buoy motion law based on catenary and cubic parabola theories, so that the key technical problem of the design of the single point buoy anti-typhoon mooring system is solved.

The invention discloses a method for making a spatial multi-curved-surface as-cast finish concrete stay in place formwork by using plywood. The method comprises the following steps of: (1) establishing a three-dimensional model of a spatial multi-curved-surface as-cast finish concrete structure; (2) simulating concrete force analysis in a computer, computing a back lining keel distance, and arranging a bottom framework; (3) introducing three-dimensional coordinate data of the three-dimensional model into an electronic total station for field lofting, and lofting an arc-shaped locus intersecting with a spatial curved surface; (4) lofting a wood back lining keel according to curves at different height sections of a building drawing; (5) paving curved plywood on the back lining keel for serving as a bottom framework; and (6) paving thin plywood on an opposite surface between the bottom framework and as-cast finish concrete for serving as a panel. The method for making the spatial multi-curved-surface as-cast finish concrete stay in place formwork by using plywood provided by the invention has the advantages of low manufacturing cost, convenience and rapidness for constructing, flat, smooth, attractive surface of the made as-cast finish concrete structure and the like, and has remarkable economic benefit and social benefit.

A folding support device and methods for constructing and using the same are provided by the present invention. A foldable support member contains a series of hinge sections and support and stress limiting members. Construction is provided enabling the device to safely collapse and stow while traveling, but to unfold and provide a gripping tension on both a support member and a support device in a reliable manner. Force analysis is provided securing the item in an upright way via a force transfer generated by the supported weight itself.

The invention discloses a method for judging temporary plugging and fracture initiation in a repeated fracturing well crack. The method specifically comprises the following steps that basic parameters are collected; a hydraulic fracture filled with temporary plugging agents is divided into two hydraulic fractures, and the stress of all points on the fracture face is calculated; a judging criterion of the temporary plugging, fracture initiation and diversion the fracture wall face after the temporary plugging agents are added into the hydraulic fractures is established by the force analysis of the fracture wall face; and the effects of different fracture length, net fluid pressure in the fracture, the temporary plugging agents, the pressure and the sealing blocking length of the temporary plugging agents on the temporary plugging and fracture initiation of the fracture wall face are analyzed quantitatively. According to the method for judging temporary plugging and fracture initiation in the repeated fracturing well crack, the organic combination of the parameters of induced stress fields produced by the extension of the hydraulic fractures and pressure changing of stratum hole fluid, the performance parameters of the temporary plugging agents, the sealing blocking length of the temporary plugging agents and the like is fully considered, the location and orientation of the fracture initiation of the temporary plugging fracture in the repeated fracturing well fracture can be effectively predicted, and the effect of repeated fracturing temporary plugging diversion transforming can be effectively improved.

The invention relates to a bituminous pavement structural analysis and increment method based on a modulus stress and strain dependence model of pavement materials. The method includes the steps of according to the structural pattern and material type of a bituminous pavement in a simulation analysis, determining the thickness and Poisson's ratio of each layer and the modulus stress and strain dependence model of the pavement materials, adopting the modulus stress and strain dependence model of the pavement materials to represent the modulus of each layer of a bituminous pavement structure, combining calculation load with interlayer combination conditions to create a calculation analysis system, using an increment method as an analysis basis, obtaining a modulus matrix of each point of theinteriors of pavement structural layers through finite element software numerical calculation, and based on the steps above, calculating the stress, strain and displacement of an arbitrary point in the bituminous pavement structure according to an elastic layered system theory. According to the method, influences caused by non-linear problems of materials on pavement mechanical calculation are taken into account to make the force analysis of the bituminous pavement structure more reasonable and complete.

The invention discloses a numerical simulation method of hydrodynamic force analysis of a deep-sea culture net cage group, comprising the following steps of: building a floating frame model; building a netting model; building an anchor line model; building a floating ball model; and solving by establishing a differential equation of motions. In the invention, a concentrated mass method and a rigid body kinematic theory are used for simulating the hydrodynamic force response of the deep-sea culture net cage group structure under the effects of waves; with the adoption of the method, anchor line tensions and floating frame motions of the deep-sea culture net cage group structure can be obtained; and according to the verification of physical experiments, the numerically simulated floating frame motions and anchor line tensions are matched with the actual floating frame motions and anchor line tensions. With the adoption of the method provided by the invention, the hydrodynamic force response of the net cage group composed of a plurality of the net cages can be analyzed and an anchor line system of a combined type net cage group can be optimized.

The invention relates to a sector segment actuating mechanism taking pressure as a control target, belonging to the technical field of continuous casting equipment in a metallurgy industry. The sector segment actuating mechanism comprises a displacement sensor, a hydraulic cylinder, a pressure sensor, an electric control system, a hydraulic system and a sector segment, wherein the hydraulic cylinder of the sector segment is provided with the displacement sensor and the pressure sensor which are matched with the hydraulic cylinder; the signal output ends of the displacement sensor and the pressure sensor are connected with the electric control system; the output of the electric control system is connected with the hydraulic system; and the hydraulic system is connected with the hydraulic cylinder of the sector segment. The sector segment can reflect the stress of a casting blank in real time by taking the pressure as the control target, solve the problems of errors caused by sensor drifting and initial roll gap setting, prevent the casting blank from internally cracking and the sector segment from being damaged due to overload because of superabundant shrinkage mass and also ensure good casting blank quality through the force analysis of the casting blank. Besides, the method can also be used for judging the position of a liquid core of the casting blank and providing accurate feedback data for the application of a dynamic soft reduction technology.

A computer cutting and sewing analog based on force analysis and deformation starts with model build based on material particle spring and central line drawing for soft tissue, rebuilding the object surface, abstracting a central line for the object center. The central line emits a width shaft and connecting with the surface, through center line to drive the surface for integral deformation. A reasonable quick bumping inspection technique is built based on this for cutting and sewing analog. It assimilates the merits of existing method with optimization and integration, realizing accurate and timely analog for computer aided cutting and sewing operation.

The invention relates to a submarine cable movement locus simulation method and system, and microsegmentation processing is performed on a cable and cable laying time, i.e., each microsegment partial(s) is a cable mass point, partial(t) represents a microsegment of cable laying time, force analysis of the cable mass points in a three-dimensional space is performed, and in combination with relationship of movement and force, a movement equation set of a function relationship of the microsegment partial(s) and time partial(t) in three directions in space is established; according to the movement equation set, an initial moment t0 and a moment t=(t0+partial(t)) correspond to position coordinates of each mass point on an underwater cable in the three-dimensional space; and according to the movement equation set, based on the position coordinates of each mass point on the underwater cable in the three-dimensional space that t0 and t=(t0+partial(t)) correspond to, position coordinates of each mass point on the underwater cable in the three-dimensional space at moment t=(t+partial(t)) are obtained, i.e., a movement locus of the underwater cable in a period of time is obtained.

Aspects of the invention are directed to piezoresponse force analysis of a material. A stimulus signal including a first frequency component is applied to a contact point on the material such that the stimulus signal actuates a portion of the material to experience a motion as a result of a piezoelectric effect. A resonant device is coupled to the contact point such that the resonant device experiences a resonant motion at the first frequency component in response to the motion of the material, the resonant motion having a greater displacement than a displacement of the motion of the material, and is substantially unaffected by mechanical properties of the material at the contact point. The resonant motion of the resonant device is detected and processed to produce a measurement representing the piezoresponse of the material at the contact point.

The invention relates to a collision position sensing method based on a six-dimensional force sensor. The collision position sensing method includes the following steps that the six-dimensional force sensor is installed between a first joint of a mechanical arm and a base; force and moment information fed back by the six-dimensional force sensor are substituted into a force analysis total equation containing gravity compensation and dynamics compensation, and acting force and moment of a collision point are obtained; and the position of the collision point in a base coordinate system can be obtained according to the acting force and the moment of the collision point. By means of the collision position sensing method, calculation of position information of point contact on the mechanical arm can be rapidly, conveniently and accurately achieved, and a robot has a higher adaptive capacity to environments.

The invention discloses a method for controlling glide flying ballistic curve damping. The method comprises the following three major steps: step 1: taking into consideration influence of earth curvature, ignoring influence of earth rotation, studying three degree-of-freedom kinematical equation of gliding of an aircraft, and acquiring condition of furthest distance of powerless gliding of the aircraft; step 2: based on the atmosphere model and the aircraft aerodynamic force model already known, performing force analysis on the longitudinal plane of the aircraft under stable gliding condition, and acquiring stable gliding ballistic curve angle of inclination gamma*; step 3: adding feedback to the control instruction, introducing ballistic curve damping control. The method is a guidance method enabling stable gliding of the aircraft, and is applicable to aircrafts having a glide ballistic curve, including a cannonball of a low speed and a short range as well as a long-distance, reentry, and hypersonic-velocity aircraft.

The invention provides a fast and accurate characterization method for a living cell atomic force microscope. The method comprises the steps that the atomic force microscope is used to acquire the substantially stable applied force range of the cell surface elasticity value and the corresponding Young's modulus value; the atomic force microscope is used to acquire the back-and-forth scanning height image of a living cell under a set imaging force; force analysis is carried out on the interaction between a probe and the cell, and the interaction between the probe and the cell is decomposed into a vertical imaging force and a horizontal lateral force; and according to the imaging force magnitude, the cell surface topography under the force and the cell surface elasticity coefficient, the cell surface morphology of the cell without applied force is calculated. The fast and accurate characterization method for the living cell atomic force microscope has the advantages of high precision, high time resolution and the like.

The invention discloses an air target missile fragment emission maximum damage algorithm. The method includes the steps of setting parameters of the intersection between a missile and an aircraft, determining the range of a point of burst, and dividing the range of the point of blast into a plurality of points of burst; conducting a force analysis on detonated fragments of the missile at the points of blast to obtain flight trajectories during the fragment emission; determining a critical part of the aircraft as a critical area, and when the flight trajectories during the fragment emission pass through the critical area and the emission speed is greater than or equal to a set speed threshold, determining the fragments as effective hit fragments; and obtaining the corresponding location ofthe point of blast where the number of effective fragments is the greatest, that is, the maximum damage location. The algorithm in the invention takes into account the influence of the air resistanceand gravity of the fragment during the flight when the force analysis is performed on the single piece of fragment, and the analysis result is more accurate.

The invention discloses a measurement method for the thickness and the flow of a gas-liquid two-phase annular flow liquid film in a vertical pipe. The method includes the following steps that (1) the pressure drop gradient dP / dz of the gas-liquid two-phase annular flow in the vertical pipe is measured, the shear stress tau<w> between a liquid film of the gas-liquid two-phase annular flow and the wall in the vertical pipe is measured; (2) a columnar control volume is selected for force analysis on a gas core, a gas core momentum equation is obtained, and an annular control volume is selected for force analysis on the liquid film to obtain a liquid film momentum equation; (3) according to the gas core momentum equation and the liquid film momentum equation, the shear stress tau in the liquid film is obtained; (4) according to the pressure drop gradient dP / dz of the gas-liquid two-phase annular flow in the vertical pipe, the shear stress tau<w> between a liquid film of the gas-liquid two-phase annular flow and the wall in the vertical pipe and the shear stress tau in the liquid film, the radius r of the gas core of the gas-liquid two-phase annular flow in the vertical pipe is calculated, and then the thickness and the flow of the gas-liquid two-phase annular flow liquid film in the vertical pipe are calculated according to the radius r of the gas core of the gas-liquid two-phase annular flow in the vertical pipe. According to the method, detection of the thickness and the flow of the gas-liquid two-phase annular flow liquid film in the vertical pipe can be achieved, the method has high detection precision, safety and reliability, and the detection cost is low.

The invention discloses an inverse installation and construction method of an indoor stage steel structure in a theater. The method includes the steps of BIM simulation analysis, measurement preparation, embedded part installation, erection of a supporting system, pre-assembling of steel girders and davits of a stage roof layer, steel girder installation of the stage roof layer, steel structure installation of a stage machine process, disassembling and dismantling of the erected supporting system and coating installation of the steel structures. According to the construction method, by adopting BIM modeling and conducting installation simulation and force analysis on the steel structures, a more scientific and economical technical scheme can be chosen, and the quality and safety problems likely to happen can be found and solved in advance, the construction quality is ensured, costs are reduced, and the construction period is shortened.

The invention provides a device and method for detecting the friction force of a continuous casting crystallizer on line. The vibrating system of the detecting device comprises hydraulic cylinders (3) each of which is provided with a pressure sensor (4) and a displacement sensor (5), wherein the two hydraulic cylinders are arranged on the two sides below a vibrating table in a bilaterally symmetrical mode; and signals detected by the two sensors are sequentially processed by a programmable controller (8), an analogue / digital (A / D) data acquisition card (9), an industrial personal computer (IPC) (10) and a communication card (11), and are transmitted to a server (12) for data storage. The detecting method comprises the following steps of: measuring the comprehensive rigidity and the equivalent damping of the vibrating system through particle swarm optimization (PSO), performing force analysis on the vibrating system, establishing force equations when the vibrating system keeps still at a vibrating balance position and in a null vibrating state and a throwing state, and calculating the difference between throwing output force and null vibrating output force so as to acquire the friction force of the crystallizer. By using the device and the method, the friction force of the continuous casting crystallizer can be accurately and reliably detected in real time on line.

The invention discloses a whole machine static stiffness matching and designing method in view of machine tool top-down design. The method comprises steps: static stiffness of each part of the machine tool in a difference place is defined; a static stiffness model for the whole machine is built; force analysis is carried out on each part of the machine tool, a force condition of each part is obtained, and normal forces and tangential forces of the machine tool body, a vertical column and a slide carriage are obtained through analysis; a function relation between deformation of each part of the machine tool and static stiffness of each part of the machine tool is built; the static stiffness model for the whole machine is built; and on the basis of the static stiffness model for the whole machine, static stiffness matching and designing are carried out. In the machine tool concept design stage, the whole machine static stiffness given by a user serves as a target, machine tool static stiffness design is carried out in a top-down mode, and in the condition in which static stiffness in three directions at the tail end of the whole machine tool is given, reasonable static stiffness for each part is obtained through matching and designing. The static stiffness of the machine tool can be estimated and controlled at the beginning of the design, the efficiency and the accuracy of design are improved, the processing precision of the machine tool is improved, product performance estimation can also be carried out, and the production cost and the manufacturing cost are reduced.

This invention discloses a supporting joint used in girders or rack, characterized in that it comprises an erection support connected with a supporting member, and connected with several joints formed from the integrated component. Said supporting joint is easy to manufacture and install, and it has firm structure and high precision, in addition, it can be used for force analysis and computing.

The invention discloses a method and a device for reducing a wind pressure to a building, which solve problems about the method and interface for accessing conventional structural calculation and analysis software and problems about the method and the device for handling noises, rainy weather and condensed water during the reduction of the action applied by the wind pressure onto the building. Passages are arranged between the windward side and leeward side of the building so as to make wind run through a building body; positions, number and cross-sectional sizes of the passages on the surfaces of the building are determined to acquire input parameter values required by the conventional structural calculation software; and the conventional structural calculation software is utilized to finish the structural calculation, force analysis and the design of a structure and components of the building. Therefore, the method and the device for reducing the wind pressure can be actually applied to engineering, engineering cost is reduced and structural security is improved; mufflers and rainwater and condensed water drainage systems are arranged in the wind passages; and the method and thedevice are mainly applied to super high-rise buildings and high-rise buildings of shallow rectangular shapes, particularly regions with strong wind and low earthquake intensity.

The invention provides a reticular deployable antenna deploying process cable force analysis method. The reticular deployable antenna deploying process cable force analysis method mainly includes steps: selecting the number and geometric parameters of peripheral truss units of a reticular deployable antenna, a material parameter D of a cable net, a geometric parameter S, a network cable topology structure and the number M of discrete working conditions of a deploying process; calculating a change motion trail of positions of connection points of trusses and the cable net; calculating a stress state of each cable unit under each working condition; fitting a changing curve F(theta) of acting force of the cable net for a boundary connection point along with changes of a spread angle; finally, using changing cable net acting force as a load, substituting the load into a flexible multiple body dynamics model, and performing dynamics analysis. The reticular deployable antenna deploying process cable force analysis method regards the deploying process of the reticular deployable antenna as a series of discrete loaded mechanism balance forms, studies strain distribution of each balance form, accurately obtains a cable force changing curve of the deploying process, and provides effective support for ground engineering to achieve influence mechanism analysis of cable net tension for the deploying process based on flexible multiple body system dynamics modeling and analysis.

The invention discloses a method for determining the safe drilling fluid density of a coal bed based on a structural element analysis model. The method has the advantages of coal bed cleat and fracture development, big rock brittleness, low strength and obvious anisotropy and discontinuity. The borehole wall instability characteristics of the method are different from those of the common sandstone stratum. The phenomenon that the traditional borehole wall stability model based on the mechanics of continuous media is difficult to be successful for solving coal bed instability problems can be eliminated. In the method, the coal bed is composed of discrete blocks. A coal briquette which has the biggest possibility of generating spallation between surface cleats is analyzed to carry out force analysis. A structural element model of collapse pressure is built by the stressed balance condition among pressure stress, shearing strength and shaft pressure. A coefficient c is introduced to judge the stable relationship of borehole pressure and borehole wall so as to judge the range of the safe drilling fluid density.

The invention provides a method and device for measuring axial force and lateral force of rod strings in a three-dimensional well. The method comprises the steps of obtaining track measure point data of the three-dimensional well, selecting one rod string between any two data points from the track measure point data to be used as a rod string unit, collecting the curvature, the length, the effective gravity, the inertia moment and the elasticity modulus of the rod string unit, collecting the first hole drift angle, the second hole drift angle, the first azimuth angle, the second azimuth angle, the well friction resistance coefficient, the stroke, the stroke frequency, the liquid dynamic viscosity in an oil pipe, the pump depth and the ratio between the inner diameter of the oil pipe and the diameter of the rod string of the track measure point corresponding to the rod string unit, determining the axial force of the second end, the axial force of the first end, and the lateral force of the unit length of the rod string unit, and determining the axial force and the lateral force of the rod strings in the three-dimensional well. The method can be used for designing and calculating the control measures of oil extraction eccentricity preventing of a sucker-rod pump, and also can be used for force analysis of the rod strings in the three-dimensional well.