713 results about "Double ring" patented technology

A new class of 16-ary Amplitude and Phase Shift Keying (APSK) coded modulations, called double-ring APSK modulation, based on an amplitude and phase shift keying constellation in which the locations of the digital signals to be encoded are placed on two concentric rings of equally spaced signal points. The APSK constellation parameters are optimised so as to pre-compensate the impact of non-linearities. The new modulation scheme is suited for being used with different coding schemes. It is shown that, for the same coding scheme, pre-distorted double-ring APSK modulation significantly outperforms classical 16-QAM and 16-PSK over a typical satellite channel, due to its intrinsic robustness against the high power amplifier non-linear characteristics. The proposed coded modulation scheme is shown to provide a considerable performance advantage for future satellite multi-media and broadcasting systems.

The invention discloses a micro-grid multi-micro-source inverter loop current and voltage fluctuation master-slave control method, which is implemented by a master controller and slave controllers. The master controller comprises a power ring, a voltage ring and a micro-grid current feedforward link. Each slave controller consists of a voltage outer ring and a current inner ring for double-ring control, and can quickly respond to voltage fluctuation caused by switching a distribution network and micro-sources near loads. When a micro-grid system is in a parallel operation mode, the master controller controls the energy output of the micro-sources of the micro-grid by setting rated active power and rated passive power of the micro-grid system, and simultaneously processes real-time voltage and real-time frequency of the distribution network to send control signals to each slave controller, so that inverters output active power and passive power required by the micro-grid system; and the inverters uniformly output voltage synchronous with the distribution network to meet the requirement of synchronization of the micro-grid and the distribution network so as to avoid generating loop current among the micro-sources.

The present invention aims to provide a cover glass for display devices, made of soda-lime glass, excellent in cutting easiness and reliability of surface strength. The cover glass for display devices of the present invention includes a chemically strengthened glass, and has a compressive stress layer having a depth of 6 to 15 μm.In the cover glass, a shape parameter determined in accordance with JIS R 1625 (1996) based on analysis of a facture stress of the cover glass measured by a coaxial double ring test is not less than 7, and strength of the cover glass when a cumulative fracture probability is 1% is not less than 450 MPa.The glass plate before the ion exchange is made of soda-lime glass.

The invention discloses double ring low voltage difference linear voltage regulator circuit. It includes error amplifier, secondary amplifier, power tube, compensating unit, output sampling network, load capacitance and load circuit, feed-forward amplifier, pull-up driving tube, pull-down driving tube, and sampling tube. It includes two loop circuits that the main one includes the error amplifier, secondary amplifier, pull-up driving tube, power tube, and output sampling network which form negative feedback loop to stably output voltage VOUT; the additional one includes feed-forward amplifier, sampling tube, pull-down driving tube, and power tube which refer to output voltage, form feed back loop to dynamically compensate circuit and further stably output voltage VOUT, and refer to load current, form positive feedback loop to increase load step change for the response circuit. The invention can supply better transient response, periphery circuit selecting, and phase margin for the circuit.

The invention discloses an automatic reducing low-deformation offshore deep-water cage, relating to a cage for marine aquiculture. The invention is capable to reduce the deformation of the cage and the flow rate of the sea water inside the cage. The invention comprises a buoyancy frame, a cage, a sinking ring, a sinking block and an anchoring rope. A supporting and lifting control ring bigger than the buoyancy frame and the diameter of the sinking ring is arranged at the one second depth of the cylindrical cage; a water inlet and a water outlet are arranged in the pipe wall of the supporting and lifting control ring; a girdle rubber inner bag which regulates the lifting and descending of the cage is arranged in the ring pipe; an air-valve is installed in the rubber inner bag and connected with the air supply by a pressure hose; between the outer ring and the supporting and lifting control ring of the double-ring buoyancy frame, the bottom outline of the cylindrical cage and the bottom sinking ring, a plurality of flexible ropes are located and connected according to the ring at geometric proportion, and a netting is arranged among the connecting ropes of the three rings; and finally, a flexibly connected automatic reducing low-deformation offshore deep-water cage with a cylindrical inside and a two-cone platform outside is formed, the stress point of the anchoring rope of the cage is arranged at the supporting and lifting control ring.

A new class of 16-ary Amplitude and Phase Shift Keying (APSK) coded modulations, called double-ring APSK modulation, based on an amplitude and phase shift keying constellation in which the locations of the digital signals to be encoded are placed on two concentric rings of equally spaced signal points. The APSK constellation parameters are optimised so as to pre-compensate the impact of non-linearities. The new modulation scheme is suited for being used with different coding schemes. It is shown that, for the same coding scheme, pre-distorted double-ring APSK modulation significantly outperforms classical 16-QAM and 16-PSK over a typical satellite channel, due to its intrinsic robustness against the high power amplifier non-linear characteristics. The proposed coded modulation scheme is shown to provide a considerable performance advantage for future satellite multi-media and broadcasting systems.

The invention provides a method for preparing light-weight fuel oil and propylene from inferior raw oil. The method comprises the following steps that: the inferior raw oil enters a first and second reaction areas of a catalytic conversion reactor in sequence to contact the catalytic conversion catalyst to undergo the primary reaction and the secondary reaction, the reaction products and the spent catalyst undergo solid-liquid separation, and the spent catalyst undergoes steam stripping and singeing in sequence and then is returned to the reactor for recycling; the reaction products are separated to obtain propylene, gasoline, catalytic wax oil and other products, wherein the catalytic wax oil enters an aromatic extraction device for separation so as to obtain extract oil and raffinate oil; and the raffinate oil is cycled to the first reaction area of the catalytic conversion reactor or / and other catalytic conversion devices for further reaction to obtain the target products of propylene and gasoline. In the method, the inferior raw oil undergoes the mild catalytic conversion, the obtained catalytic wax oil undergoes aromatic extraction, and the extract oil richly contains double ring arenas and is a quite good chemically raw material; and the raffinate oil richly contains alkanes and naphthenic hydrocarbons, and is quite suitable for catalytic conversion, so that the highly efficient utilization of gasoline resources is realized.

[Problems] To provide a tunable laser with high reliability and high performance, and of low cost.[Means for Solving Problems] A tunable laser (10) comprises a double ring resonator (11) where ring resonators (111, 112) of different sizes are coupled through a directional coupler (122), an LD side waveguide (13) connected at one end (131) to the ring resonator (111) through a directional coupler (123), a reflection side waveguide (14) connected at one end (141) to the ring resonator (112) through a directional coupler (123), a PLC board (15) on which the ring resonator (111) and the like are formed, a high reflection film (16) provided at the other end (142) of the reflection side waveguide (14), an LD chip (17) having a low reflection film (18) formed on either of two opposing emission end faces (171, 172) and coupled optically with the other end (132) of the LD side waveguide (13), and film-like heaters (191-194) for varying the resonance wavelength of the double ring resonator (11).

The invention relates to an area high-permeability photovoltaic energy storage system and an energy management method thereof. The area high-permeability photovoltaic energy storage system comprises a photovoltaic battery array, an energy storage battery assembly, a deflector, a load, an area electrical network and an energy management system. When the area high-permeability photovoltaic energy storage system is connected to a network for operation, the energy management system carries out three-ring control of a power outer ring, a voltage middle ring and a current inner ring, and realizes the maximum utilization of photovoltaic energy, active power smooth input and reactive power compensation through the largest-power tracking of the photovoltaic battery array and the charging and discharging management of the energy storage battery assembly; and when the area high-permeability photovoltaic energy storage system is isolated for operation, the energy management system realizes double-ring control of a voltage / frequency outer ring and the current inner ring for providing constant voltage and frequency for the area high-permeability photovoltaic energy storage system and maintaining the stable operation of the system. The photovoltaic generating and energy storage technologies are fully combined so that photovoltaic and energy storage coordinated control is realized, the network point power fluctuation is inhibited, the grid-connected power generation of an area high-permeability photovoltaic power generation system is realized, and the system energy management efficiency, the power supply reliability and electric energy quality are effectively improved.

A double-ring dead-beat prediction control method for a permanent magnet synchronous motor based on disturbance estimation compensation comprises the following steps: establishing a discrete current prediction model of the permanent magnet synchronous motor, and designing a dead-beat current prediction controller; designing a sliding mode disturbance observer to estimate stator current and parameter disturbance; designing a dead-beat speed prediction controller; and designing a sliding mode disturbance observer to observe and compensate the load torque. According to the invention, under the condition that motor model parameters are not matched, the method achieve the accurate current control; under the condition that the dead-beat speed prediction controller is sensitive to load change, the method achieves the improvement of the dynamic and static performance and the anti-disturbance performance of the speed outer ring through load torque observation and compensation.

A semiconductor laser comprises two optical ring resonators, each comprising an optical waveguide electrically pumped to provide optical gain. The two ring resonators have different round-trip optical path lengths, and are coupled to each other through a half-wave optical coupler. The half-wave optical coupler has a predetermined cross-coupling coefficient and a 180-degree cross-coupling phase. The cross-coupling coefficient is substantially less than the self-coupling coefficients in order to achieve an optimal single-mode selectivity of the laser. The first ring resonator has an optical path length such that its resonant wavelengths correspond to a set of discrete operating channels. The second ring resonator has a slightly different length so that only one resonant wavelength coincides with one of the resonant wavelengths of the first ring resonator over the operating spectral window. The lasing action occurs at the common resonant wavelength. In operation, at least a portion of the optical waveguide in each of the first and the second ring resonators are forward biased to provide substantially equal round-trip optical gains. The second ring resonator is tuned by varying the effective refractive index of a portion of the waveguide through an electrical means, resulting in wavelength switching among the set of discrete operating wavelengths as determined by the first ring resonator.

The double-ring coupled all optical buffer storage based on 3x3 fiber coupler stores light signal has its read / write operation under control of one other light signal. Two side ports of the 3x3 fibercoupler constitute the double-ring structure via fiber feedback and the middle ports are used as the input and output of the buffer storage. Control light is led in and led out one fiber ring via twoWDM fiber coupler, and the phase difference between the two ring light signals is altered by means of cross phase modulation effect to realize the write-in and real-out of light signal in fiber ring.The control light signal may be positive logic one or negative logic one. If necessary, light amplifier may be added into the fiber ring for power compensation. Several buffer storages can be constituted into one parallel signal light buffer storage.

A dispensing device and a storage device for dispensing a formulation as a spray. The storage device has multiple separate and pre-metered doses of the formulation in receptacles or cavities. In order to allow a very compact arrangement, the receptacles or cavities are arranged in a first group and a second group axially offset, and preferably, forming a double ring arrangement, and the storage device is rotatable and axially moveable for dispensing the doses one after the other.

A damping-force generating device included in a shock absorber includes: a main valve that opens and closes for controlling a flow of oil (working fluid) caused by sliding of a piston in a cylinder and thereby generates a damping force; a first pressure chamber and a second pressure chamber separated by the main valve; a compression-side inlet check valve and an extension-side inlet check valve that allow only inflow of the oil into the first pressure chamber; and a compression-side outlet check valve and an extension-side outlet check valve that allow only outflow of the oil from the second pressure chamber. The first pressure chamber and the second pressure chamber are formed in a substantially double-ring structure.

The invention provides a tunable laser with high reliability and high performance, and of low cost. A tunable laser (10) comprises a double ring resonator (11) where ring resonators (111, 112) of different sizes are coupled through a directional coupler (122), an LD side waveguide (13) connected at one end (131) to the ring resonator (111) through a directional coupler (121), a reflection side waveguide (14) connected at one end (141) to the ring resonator (112) through a directional coupler (123), a PLC board (15) on which the ring resonator (111) and the like are formed, a high reflection film (16) provided at the other end (142) of the reflection side waveguide (14), an LD chip (17) having a low reflection film (18) formed on either of two opposite emission end faces (171, 172) and coupled optically with the other end (132) of the LD side waveguide (13), and film-like heaters (191-194) for varying the resonance wavelength of the double ring resonator (11).

The invention discloses a dual-loop DLL-based three-segment type high-precision time-to-digital conversion method and circuit. According to a measured time segment, a high-middle-low combined segmental type quantization method is adopted. A high-segment bit counting type quantizer in three-segment type TDC (time-to-digital conversion) is driven by a high-frequency stabilizing clock which is inputted from the outside, so that a wide-range stable distance measuring range can be realized; a middle-segment bit TDC is formed by a first DLL voltage controlled delay chain; high-segment bit subdivision can be realized through an asynchronous sampling mode, and repeatable uniform phase distinguishing can be accomplished in a stable clock period; a phase position at a termination time point is decoded, so that a middle-segment quantization function can be accomplished; and according to quantization errors generated by time-to-digital conversion in a middle-segment bit, error time is extracted, a low-segment bit accomplishes further quantization processing, and therefore, higher measurement precision can be realized.

The invention relates to an antenna tracking system used for a mobile satellite communication system. The antenna tracking system is based on combination of multiple sensors for performing posture measurement, and fusion and estimation are performed on the combination of magnetic strength information, acceleration information and angular speed information. The method of three-axis stabilization plus dynamic search is adopted, and an inner ring for combined posture measurement compensation is used for realizing the three-axis stabilization, so as to prevent the posture of a carrier from being affected by the environment; and a strength signal output by a digital receiver is introduced into a controller as a feedback signal for constituting an outer ring for tracking a level signal, so that the way of double-ring nestification dynamic search of the maximum point in the signal can be formed for performing error compensation. The specific algorithm is as follows: utilizing a carrier rotation angular speed component measured by a three-axis gyroscope to perform Kalman filtering on a measured gravitational acceleration component and a geomagnetism induction density component, removing interferences caused by accelerated motion and an external magnetic field, further getting a true value, and finally utilizing the value to perform the posture resolution.

A semiconductor laser comprises two optical ring resonators, each comprising an optical waveguide electrically pumped to provide optical gain. The two ring resonators have different round-trip optical path lengths, and are coupled to each other through a half-wave optical coupler. The half-wave optical coupler has a predetermined cross-coupling coefficient and a 180-degree cross-coupling phase. The cross-coupling coefficient is substantially less than the self-coupling coefficients in order to achieve an optimal single-mode selectivity of the laser. The first ring resonator has an optical path length such that its resonant wavelengths correspond to a set of discrete operating channels. The second ring resonator has a slightly different length so that only one resonant wavelength coincides with one of the resonant wavelengths of the first ring resonator over the operating spectral window. The lasing action occurs at the common resonant wavelength. In operation, at least a portion of the optical waveguide in each of the first and the second ring resonators are forward biased to provide substantially equal round-trip optical gains. The second ring resonator is tuned by varying the effective refractive index of a portion of the waveguide through an electrical means, resulting in wavelength switching among the set of discrete operating wavelengths as determined by the first ring resonator.

The invention relates to a double-layer cascaded dual-polarized broadband absorbing type frequency selective surface. A conventional wave absorbing frequency selective structure is designed to be a bandpass type frequency selective structure which has limited pass band width and has difficulty in covering low frequency. According to the invention, a double-ring reflective plane is adopted, a waveabsorbing ring is designed on the other surface of the reflective plane, and the double-layer cascaded dual-polarized broadband absorbing type frequency selective surface is constructed by the combination of a single-ring circuit analog absorber. Therefore, insertion loss in a low frequency passband is low, and an extremely wide absorbing band can be generated near a high frequency place.

The invention provides a three-dimensional network on chip (NoC) structuring method by using a horizontal-plane network structure and a flexible imaginary-plane network structure, wherein, the horizontal-plane network of which the network topology adopts a De Bruijn picture is a plane extending along the X direction and the Y direction; while the imaginary-plane network is a curved surface extending along the three directions of X, Y and Z, the network can be formed by connecting certain nodes of each layer of the horizontal-plane network according to the requirement for solving certain problems such as reducing the wiring complexity or improving the fault-tolerant character, namely, the nodes are not necessarily in a vertical plane. The invention also provides two kinds of imaginary-plane structuring methods comprising a De Bruijn picture structure and a double-ring structure. The first method fully utilizing that the De Bruijn picture allows shorter routing algorithm reduces average hop times in the data transmission, provides a small network delay and has a better fault-tolerant character; the second method improves the transmission efficiency by using the characteristics of low wiring complexity of a ring structure and high data transmission speed and by combining the horizontal-plane network utilizing the advantage of small network diameter of the De Bruijn picture.

The invention relates to a laminar flow cooling system of a hot milling band steel double ring controlling layer flow. The cooling system comprises a water spraying group aligned along an output roller passage, a controller used for controlling the water spraying groups, a front end temperature measuring instrument, a back end temperature measuring instrument, an intermediate temperature measuring instrument; wherein, the output terminals of the temperature measuring instruments are connected with the controller. The control loop of the system is divided into a first single closed ring loop and a second single closed ring loop with the intermediate temperature measuring instrument as the boundary. The front end temperature measuring instrument is the feedforward temperature measuring instrument of the first single closed ring loop, and the back end temperature measuring instrument is feedback temperature measuring instrument of the second single closed ring loop. In addition, the intermediate temperature measuring instrument is the feedback temperature measuring instrument of the first single closed ring loop and the feedforward temperature measuring instrument of the second single closed ring loop. The laminar flow cooling system of the invention adopts two closed ring controlling loops, the boundaries of which are the boundary between the front end temperature measuring instrument and the intermediate temperature measuring instrument, and the boundary between the intermediate temperature measuring instrument and the back end temperature measuring instrument. The invention reasonably adopts the actual measured temperature value and the module predicted temperature value of the temperature measuring instruments to effectively control the cooling process and the cooling time as well as the cooling speed.

The invention discloses a single-component phosphor-nitrogen double-ring cage-shaped macromolecular intumescent flame retardant as well as a preparation method and an application thereof. the preparation method comprises the following steps: at 90-110 DEG C, a nucleophilic substitution reaction is carried out between pentaerythritol and phosphorous oxychloride, and PEPA is obtained; a reaction between PEPA and cyanuric chloride is carried out at -5-10 DEG C for 3-6 hours, a reaction between a product and a diamine compound is carried out at 50-60 DEG C for 5-10 hours, and then a reaction between the product and the diamine compound is carried out at 90-110 DEG C for 5-10 hours; finally the single-component phosphor-nitrogen double-ring cage-shaped macromolecular intumescent flame retardant is obtained for flame retardant modification of polymers. Compared with the prior art, the prepared single-component macromolecular intumescent flame retardant has the advantages of high flame retardation efficiency, good compatibility with polymers, etc.; the intumescent flame retardant whose weight is 20-25 wt% of polypropylene can be added into the polypropylene for endowing the polypropylene with good flame retardation performance, and the intumescent flame retardant can be widely applied to the fields of internal and external decorative parts of automobiles, furniture and electric appliances, wires and cables, building material, etc.

The invention discloses a bicyclo ring cage substituted sesquialter oxosilane and the method for preparing the same and its application. The compound possesses high sesquialter constructure, the core is cage sesquialter oxosilane, the eight apical angle are 1- oxo- 1- phosphora- 2, 6, 7- trioxa bicyclo [2, 2, 2]- 4- methylene sorbate. The method comprises: dissloving catalyst and solvent, adding bicyclo ring cage coordination silicon, reacting while stirring at room temperature; heating to 60- 70 Deg .C, stopping reaction, sucting, distilling part of solvent from filtering liquid and putting it in fridge for cooling, a large amount of crystal will be generated two days later, putting it at room temperature for 1 hour to make the ethandiol crystal disslove, sucting and drying the crystal at 60 Deg. C. The epoxide resin adjuvant is characterized by ability of increasing toughness, fire-retardancy, heat-proof quality, abradability, weatherability and anti ultraviolet absorption for epoxide resin, and hardening function.

The invention claims to protect a dual-wavelength tunable short pulse fiber laser, mainly including pumping sources (1)(10), wavelength division multiplexers (2)(4)(6)(11), gain fiber (3)(12), a graphene saturable absorber (5), fiber couplers (7)(13), circulators (16)(17), reflection type adjustable filters (8)(14) and broadband fiber environments (9)(15) formed by 50:50 fiber couplers. The dual-wavelength tunable short pulse fiber laser provided by the invention adopts a double-ring cavity or double-linear cavity structure, the wavelength division multiplexers (4)(6) and the graphene saturable absorber (5) serve as a common branch of the double-ring cavity or double-linear cavity structure, utilizes the advantages of wide wavelength absorption range, smooth absorption, low saturation intensity and ultrafast recovery time of the graphene saturable absorber, and combined with the reflection type adjustable filters, stable output of synchronous short pulses with tunable single wavelengths and large dual-wavelength intervals of the fiber laser can be realized.

The invention relates to a positioning system for assisting in spine minimally invasive surgery. The positioning system mainly comprises a degree mechanical arm and a path positioner. The path positioner comprises a flange short locking component, a lifting and sliding component and a double-ring positioning assembly. The mechanical arm can be installed on a trolley; the path positioner is fixed to the tail end of the mechanical arm through the flange short locking component. The lifting and sliding component is connected with the flange short locking component through a clamping and locking body; the double-ring positioning component is connected with a lifting and translation component through a screw. The double-ring positioning assembly is provided with a first positioning ring and a second positioning ring which are used for a guide needle to penetrate through in sequence to position the guide needle, and the first positioning ring and the second positioning ring are separated with each other and concentrically arranged; the lifting and sliding component can drive the double-ring positioning component to conduct translation motion in the axial direction of two rings. The positioning system for assisting in the spine minimally invasive surgery can assist a doctor in accurately positioning the transplanting path of the spine minimally invasive surgery under the condition that the radiation frequency is few.

The invention discloses a power-assisted three-ring injection syringe which comprises a syringe main body and a spiral pushing rod, wherein the syringe main body comprises a tail end and a near end; the spiral pushing rod comprises a tail end and a near end; the tail end of the spiral pushing rod is connected with a rubber stopper and is inserted into the syringe main body; the near end of the spiral pushing rod is sheathed with an inner sleeve; a nut, which is matched with the inner sleeve, is sheathed on the syringe main body; a double-ring sleeve is sheathed outside the inner sleeve and is connected with the inner sleeve; a first spring is sheathed on the spiral pushing rod and is sealed by the inner sleeve; a second spring is sealed by the double-ring sleeve and the inner sleeve; and a locking part, which is used for clamping the spiral pushing rod, is arranged on the inner sleeve. By the power-assisted three-ring injection syringe, the flow rate and the flow quantity required for the radiography can be easily achieved; and therefore, the power-assisted three-ring injection syringe is very convenient for operators to operate.

The invention discloses a method for preparing a selective hydrogenation ring-opening catalyst for aromatic hydrocarbons with double rings or more. The method is characterized in that the selective hydrogenation ring-opening catalyst for aromatic hydrocarbons with double rings or more is prepared from a carrier, active ingredients and aids, wherein the carrier is prepared from alumina, amorphous silica-alumina, a modified small grain Beta-type molecular sieve and an SPAO-5 / ZSM-5 composite molecular sieve; the active ingredients at least include an oxide of Mo or W and at least include an oxide of Co or Ni; and the aids refer to one or two out of F and P. The invention also relates to a preparation method of the catalyst and a method for synthesizing the SPAO-5 / ZSM-5 composite molecular sieve. The catalyst is effectively matched with a hydrogenation active center, an isomerization active center and a cracking active center, so that the catalyst has excellent aromatic hydrocarbon hydrogenation ring-opening selectivity in the hydrogenation process of low-quality distillate oil enriched in aromatic hydrocarbons with double rings or more.

The invention provides a high-sensitivity terahertz micro-fluid sensor based on band gap plasma resonance, and relates to the field of design of sensors. The high-sensitivity terahertz micro-fluid sensor comprises a cap, an etching groove, a metal array periodic structure layer, a micro-fluid channel, a metal reflective mirror, a substrate medium chip and a liquid inlet / output channel from top tobottom, wherein the cap is etched with the etching groove, and a metal micro-structure layer is attached to the etching groove; the metal plane reflective mirror is arranged on a substrate. The high-sensitivity terahertz micro-fluid sensor has the advantages that the metal array micro-structure uses the center-symmetric double-circular ring structure as a metal micro-structure array, so that the characteristics of no sensitivity to polarization and double resonance are realized; on the basis of double rings, the number of resonance rings can be increased, so as to realize the higher-order resonance response and multi-resonance detection; compared with the sensor without the etching groove, the sensitivity of the sensor provided by the invention is increased by 25% or above; compared with the existing sensor, the sensitivity is greatly increased; the structure is simple, and the processing and use are easy.

A catalytic conversion process can convert inferior feedstock to high quality fuel oil and propylene. A inferior feedstock is introduced into first and second reactor zone, wherein the feedstock carry out first step and second step reactions by contacting with catalytic conversion catalyst. Product vapors separate from spent catalyst by gas-solid separation. The spent catalyst is stripped, regenerated by burning off coke and then returns to reactor. The product vapors are introduced into separation system to obtain propylene, gasoline, diesel, fluid catalytic cracking gas oil (FGO) and other products. The FGO is introduced into hydrotreating unit and / or extraction unit to obtain hydrotreated FGO and / or extracted FGO. Said hyrotreated FGO and / or extracted FGO return to the first reactor zone and / or another catalytic cracking unit to obtain propylene and gasoline. The extracted oil of said FGO is rich in double ring aromatics which are good chemical materials. The raffinate of said FGO is rich in chain alkane and cycloalkane which are suitable for catalytic cracking. More particularly, the invention relates to a process to utilize petroleum oil resources efficiently for decreasing the yield of dry gas and coke significantly.