153results about How to "Take convenience" patented technology

A system is described for management of an operations area. The management system includes a central processing component with one or more central processors. An active monitoring system component is connected to the central processor. The active monitoring system includes tags and readers for individual identification of one or more tagged entities. The active monitoring system component is arrayed to create a management zone. The tags and readers are linked to the central processing component such that information from the tags and readers is received and analyzed by the central processing component. A passive monitoring system component is connected to the central processor. The passive monitoring system identifies non-tagged entities entering the management zone and additional information is communicated to the central processing component for analysis.

The invention discloses a device and a method for detecting sulfur trioxide (SO3) in flue gas on line. The device comprises a flue gas collecting unit, a gas liquid separator, a gas phase detection unit, a first solution tank, a liquid phase detection unit and a digital control unit, wherein the gas liquid separator is used for condensing SO3 in the flue gas from a flue gas sampling unit into sulfuric acid liquid drops and separating the sulfuric acid liquid dropsfrom gas phase; the gas phase detection unit is used for measuring the flow of the gas phase from the gas liquid separator; the first solution tank is used for providing an absorption liquid to the gas liquid separator and mixing the absorption liquid with the sulfuric acid liquid drops to form mixed liquid; the liquid phase detection unit is used for measuring the mass of the transformed SO3 in the mixed liquid from the gas liquid separator; and the digital control unit is used for calculating the SO3 concentration of the flue gas according to the detection results of the gas phase detection unit and the liquid phase detection unit. According to the device and the method, on-line measurement of the SO3 of the flue gas is realized, the SO3 of the flue gas is sampled and the SO3 content is analyzed, so that a coal-fired power plant can take corresponding measures conveniently, the SO3 content of the flue gas is controlled, the corrosion to a flue and equipment is reduced, and the heat loss due to exhaust smoke of a boiler is reduced to the maximum degree.

The production process of red brass pipe includes the steps of: fusion casting, heating, extruding, finishing, acid pickling, inspection, rolling, cutting to required size, inspection, annealing, acid pickling, forming head, drawing, finishing, inspection, deoiling, and product annealing. The present invention features that in common pressure processing apparatus, with common brass as material and through extrusion to generate red, acid pickling to increase color, drawing to decrease color, further acid pickling to increase color and annealing to maintain color, red brass pipe with high anticorrosion and homogeneous performance may be produced in low cost.

The invention discloses a liquid sampling device. The liquid sampling device comprises a base, wherein an analysis instrument body is arranged on the base, a first sliding chute and a second sliding chute are respectively formed in one side, relative to the base, of the analysis instrument body, a rotating rod and a sliding rod are respectively arranged in the first sliding chute and the second sliding chute, and two ends of the sliding rods are respectively fixedly connected with opposite side walls in the second sliding chute; and the rotating rod and the sliding rods are respectively sleeved with two first siding blocks and two second sliding blocks, a first rotating rod and a second rotating rod are repserctivley arranged between the two first sliding blocks and the two sliding blocks,springs are ranged between the first rotating rod and the second rotating rod, and the first rotating rod and the second rotating rod are arranged in a crossing manner. By utilizing a automatic online analysis instrument for copper and silver in water, water samples at different water levels in the field can be conveniently collected, and impurities can be effectively isolated, so that the analysis accuracies of copper and silver in water are improved.

The invention discloses a device and a method for tracking frozen soil active layer water movement and underground ice freeze-thaw process. The tracking device comprises a precipitation tracer releasing device, an active layer water and underground ice freeze-thaw simulating device, and a drainage collecting device. The precipitation tracer releasing device is used for mixing a man-made tracer with natural water body to label water and form rain intensity controllable simulated precipitation; the active layer water and underground ice freeze-thaw simulating device contains test soil and is used for monitoring soil temperature and soil water content in real time; and the drainage collecting device is used for collecting the produced water. The device and the method disclosed by the invention can directly observe the active layer water and underground ice in every space of the test soil at different time periods of precipitation runoff generation, underground ice development, underground ice thawing, and so on, can automatically monitor ground temperature and soil water content, and can conveniently and rapidly collect underground ice and soil water samples in every space in the freeze-thaw process. The solute and isotopic tracer technique has strong physical basis, and can improve observation efficiency.

The invention relates to a spiral-stirrup square steel tube concrete column comprising a square steel tube, a spiral stirrup and concrete. The spiral-stirrup square steel tube concrete column is characterized in that the square steel tube is connected with the spiral stirrup by spot welding to form a spiral-stirrup square steel tube, and the concrete is directly cast into the spiral-stirrup square steel tube. The spiral-stirrup square steel tube concrete column integrates the advantages of a square steel tube concrete column and a round steel tube concrete column and has the advantages of simple node, convenience in processing, short construction period, convenience in the adotpion of fire-prevention plates and the like because the outer part of the spiral-stirrup square steel tube concrete column is the square steel tube; and because the spiral stirrup is arranged in the spiral-stirrup square steel tube concrete column, the restraining capacity of the square steel tube on the core concrete is enhanced so that the bearing capacity of the steel tube concrete column is increased, and the area of a column section is reduced. The spiral-stirrup square steel tube concrete column has simple production process and high production efficiency and is especially suitable for the structures of high-rise buildings.

The invention discloses an intelligent environment monitoring system which comprises an information collecting unit, a PM 2.5 detecting unit, a central processor, a controller, an air purification unit and a back-end server. The information collecting unit comprises a temperature and humidity sensor, an air pressure sensor and an air speed sensor; the PM 2.5 detecting unit is used for detecting concentration data of indoor and outdoor particle matters, with the particle diameter being smaller than 2.5 [mu]m, of a fortified area; and the central processor is used for receiving electrical signals converted by all numerical values detected by the information collecting unit, and all the numerical values are compared with the threshold values of the temperature, the relative humidity, the absolute pressure intensity, the air speed, the air volume, the PM 2.5 concentration. According to the monitoring system, indoor and outdoor environment-related parameters and the PM 2.5 concentration are monitored in real time, starting and stopping of an air purification device and a temperature and humidity regulation device are automatically controlled, the indoor air quality and environmental comfort level are maintained, and the time and cost for artificial regulation and control are saved.

The invention provides a stone cutting method in which cooling water can be recycled, and relates to the field of stone cutting. The stone cutting device with recyclable cooling water includes a cutting table, an operation support box is welded and fixed on the right side of the top of the cutting table, and a cutting motor is installed on the left side of the operation support box, and the cutting motor is far away from the side of the operation support box. A protection plate is fixedly connected to the side, and a support seat is arranged above the cutting table and on the left side of the operation support box. The stone cutting device with recyclable cooling water has a simple structure and is easy to use. After the water is sprayed out by the sprinkler head, it will flow into the confluence tank through the flow tank, and the used water will be discharged through the outlet pipe after the confluence of the confluence tank. It flows into the water storage tank and is preserved. When it is used, the stored water can be pumped out from the water storage tank through the water pump through the water pump, so that the water after use can be recycled, avoiding direct flow into the ground and causing water pollution. The problem of wasting resources.

The invention discloses a medicine automated management device. The device comprises a box body. A cross plate is arranged in the box body. The left side and the right side of the upper end face of the cross plate are welded with a vertical plate. The top of the cross plate is provided with a plugging groove. A separating plate is plugged in the plugging groove. The lower end face of the cross plate is welded with a spring. The lower end of the spring is fixedly welded with the bottom of the box body. The top of the box body is provided with a top cover. The left side and the right side of the top cover are provided with buckle bodies. The left side and the right side of the top of the box body are provided with buckle heads clamped with the buckle bodies in a cooperation manner. A movement adjusting structure is arranged under the box body. The medicine automated management device can place medicine in various different sizes in a classified manner, and the medicine can automatically rise to the top of the box body, providing convenience for people to take. The device is convenient to move, simple in operation, and fast in positioning, and has good applicability, and is suitable for large-scale popularization.

The invention provides a stone cutting device in which cooling water can be recycled, and relates to the field of stone cutting. The stone cutting device with recyclable cooling water includes a cutting table, an operation support box is welded and fixed on the right side of the top of the cutting table, and a cutting motor is installed on the left side of the operation support box, and the cutting motor is far away from the side of the operation support box. A protection plate is fixedly connected to the side, and a support seat is arranged above the cutting table and on the left side of the operation support box. The stone cutting device with recyclable cooling water has a simple structure and is easy to use. After the water is sprayed out by the sprinkler head, it will flow into the confluence tank through the flow tank, and the used water will be discharged through the outlet pipe after the confluence of the confluence tank. It flows into the water storage tank and is preserved. When it is used, the stored water can be pumped out from the water storage tank through the water pump through the water pump, so that the water after use can be recycled, avoiding direct flow into the ground and causing water pollution. The problem of wasting resources.

The embodiment of the invention discloses a wireless network detection method and apparatus, a storage medium and a terminal. The method comprises the following steps: obtaining an ordinary data frametransmitted in a wireless local area network where a first terminal is located, wherein the ordinary data frame is an ordinary data frame interacted between a second terminal in the wireless local area network and a wireless hotspot; obtaining a source internet protocol IP address from the ordinary data frame; and judging whether the IP address is from the outside of the wireless local area network, and determining the reason why the first terminal cannot access the Internet according to the judgment result. By adoption of the technical scheme in the embodiment of the invention, the reason why the first terminal cannot access the Internet can be analyzed, the wireless network detection function of the terminal is enriched, and the user can conveniently take corresponding measures according to the analysis result.

The invention discloses an aerating device for an pitot. The aerating device mainly comprises a total pressure connecting pipe, a middle end cover, a static pressure connecting pipe, an end cover and a sealing component. The aerating device is characterized in that air current is injected from the outside to compress the sealing component in the static pressure connecting pipe, and a rubber part of the sealing component is enabled to deform, thereby plugging the pitot needing to be tested, preventing circumferential rotation of the pitot, overcoming an acting force applied in the axial direction of the pitot, preventing axial drifting of the pitot, reducing unstable factors in the aerating process of the pitot, and facilitating the improvement on performance detection precision of relevant sensors inside the pitot and convenience and quickness of actual operation. According to the aerating device for the pitot, disclosed by the invention, a segmented adjustable structure can be realized; compared with a traditional aerating device, the aerating device disclosed by the invention has the advantages that the defects of being heavy in handling and tedious in operation and long time for replacing testing parts, and the like of the aerating device are overcome; the aerating device also has the advantages of good sealing effect, light weight, convenience in carrying and operation, high working efficiency and the like, and can adapt to multiple operation environments.

The invention discloses a spiral rotating shaft type local reverse circulation core drill bit. The spiral rotating shaft type local reverse circulation core drill bit at least comprises a connector, a transition element, a communication element, an inner pipe and an outer pipe. The upper end of the connector is connected with a drill rod. The middle section of the connector is connected with the outer pipe. The lower end of the connector is connected with the transition element. The hollow transition element is internally provided with the communication element. The outer portion of the lower end of the communication element is connected with the inner pipe through an inner pipe connector. The inner pipe is arranged in the outer pipe in a sleeved mode. The outer pipe is connected with a reamer and a core drill head. The spiral rotating shaft type local reverse circulation core drill bit further comprises a spiral rotating shaft. The spiral rotating shaft is installed in the hollow communication element after being supported through a pair of conical roller bearings and two bearing bases. Meanwhile, the upper end of the spiral rotating shaft is connected into the connector, the interior of the lower end of the communication element leads to the inner pipe after being in threaded connection with a one-way part base, a large thrust bearing is arranged between the transition element and the communication element, a small thrust bearing is arranged between the transition element and the spiral rotating shaft, and the 'two-pipe single-rotating' effect in the drilling process of the drill bit is achieved. According to the spiral rotating shaft type local reverse circulation core drill bit, the spiral blade and two-pipe single-rotating reverse circulation working principles are combined, and the collecting rate of drill cores is effectively improved.

The invention relates to the technical field of automobile interior decoration, A vehicle-mounted cup holder is disclosed, the vehicle-mounted cup holder includes a cup holder body, A side wall of thecup holder body is provided with a cavity, a first support plate and a second support plate are fixedly connected with the cup holder body, a second support plate is slidably connected with a slidingrod, one end of the sliding rod is fixedly connected with a limiting plate, both sides of the sliding rod are slidably connected with a first pushing rod, an elastic pulling rope is connected betweenthe lower end of the sliding rod and the first pushing rod, and a through hole is arranged on the side wall of the cup holder body; A first cylinder body and a second cylinder body are arranged in the cavity, a piston is slidably connected with the first cylinder body, and a second push rod is fixedly connected with one side of the piston block; An elastic air bag is fixedly connected with the inner surface of the cup holder body; The second cylinder body is provided with a baffle plate sliding through the side wall of the second cylinder body. The invention has the advantage that the water cup can be prevented from being broken by collision.

The invention discloses a spiral electric grain sampler which comprises a sampling tube, wherein a sampling box is moveably connected with the right side of the sampling tube; a chassis is fixedly connected with the right side of the sampling box; a discharging pipe is arranged at the bottom of the sampling box; a sampling bag is moveably connected with an inner chamber of the discharging pipe; abase is fixedly connected with the bottom of the inner chamber of the chassis; a sampling chamber is arranged on the left side of the sampling tube; a motor is fixedly connected with the top of the base; a rotating shaft is fixedly connected with an output end of the motor. According to the invention, the sampling tube, the sampling box, the chassis, the discharging pipe, the sampling bag, the base, the spiral blade, the material taking chamber, the limiting rod, the groove, the cross plate, the spring column, the lug boss, the rotating shaft and the motor are combined in use for solving the problems of the traditional electric grain sampler that the sampling box is always fixed at the bottom of the sampler, the grain condition cannot be viewed in time after the grains are collected and the traditional electric grain sampler is in large size and is inconvenient for carrying.

The invention relates to a garbage can, and particularly relates to a garbage can in an obstetric ward. The technical problem to be solved by the invention is to provide a garbage can in an obstetricward and capable of storing garbage in the obstetrics department in a classified manner and effectively preventing the smell of the garbage from diffusing. In order to solve the abovementioned technical problem, the invention provides a garbage can in an obstetric ward. The garbage can comprises a first collection box and the like, wherein a storage mechanism is connected into the first collectionbox, and an opening-closing mechanism is connected to the top of the first collection box. The garbage can disclosed by the invention achieves the effects of being capable storing garbage in the obstetrics department in a classified manner and effectively preventing the smell of the garbage from diffusing; and various milk powder packages and various food garbage are generated due to the occurrence of newborn infants in the obstetrics department, and can be thrown into a second collection box at the left side; the paper diapers, wiping paper and the like of the infants can be thrown into a second collection box at the right side, and in this way, classified storage for the garbage is realized.

The invention provides a smart phone-based transformer station storage battery status cloud service monitoring system and method. The system comprises a storage battery set data collecting unit, a cloud service platform and a smart phone terminal, wherein the storage battery data collecting unit is connected with the cloud service platform, and the cloud service platform is connected with the smart phone terminal. The smart phone-based transformer station storage battery status cloud service monitoring system can conveniently obtain the status of storage batteries in real time and is very significant. According to the smart phone-based transformer station storage battery status cloud service monitoring system, the smart phone serves as a terminal device for power system operation and maintenance personnel and management personnel to monitor and receive the status information of the storage batteries of a transformer station in real time, and by means of the features of cloud service, can flexibly, safely and conveniently store, analyze and transfer the storage battery status collected from the transformer station, thereby achieving real unattended operation.

The invention discloses an on-line analyzer sampling device for total copper and total silver in water. The on-line analyzer sampling device comprises a base, wherein an analyzer body is arranged above the base; a second chute and a first chute are respectively formed in one side opposite to the base, of the analyzer body; a rotating rod and a sliding rod are respectively arranged inside the firstchute and the second chute; two ends of the sliding rod are respectively fixedly connected with opposite side walls inside the second chute; the rotating rod and the sliding rod are respectively sleeved by two first sliding blocks and two second sliding blocks; a first rotating rod and a second rotating rod are respectively arranged between the two first sliding block and the two second sliding blocks; a spring is arranged between the first rotating rods and the second rotating rods; the first rotating rods and the second rotating rods are arranged in a cross manner. By adopting the on-line analyzer sampling device for total copper and total silver in water, water samples at different water levels can be conveniently acquired, impurities are effectively baffled, and the analysis accuracyfor copper and silver in water is improved.

The embodiment of the invention discloses a close contact person infection risk assessment method and device, electronic equipment and a storage medium, and the method comprises the steps: obtaining a close contact person network which comprises at least one community, wherein the community comprises a plurality of nodes; initializing the community according to the node type of each node in the at least one community; updating infection parameters of each node in the at least one initialized community based on a label propagation algorithm; and determining the infection risk level of the corresponding node according to the infection parameter of each node. According to the embodiment of the invention, the infection risk of the close contact person is rapidly determined, and the risk assessment efficiency is improved; and the infection risk can be quantified so that the infection risk of the close connection personnel can be more intuitively expressed, and the adoption of epidemic situation protection measures is more facilitated.

The invention discloses a puncturing sampling device for medical oncology. The puncturing sampling device comprises a sampling needle drum, a clamping mechanism, a pushing-pulling shaft, a sampling mechanism and a secondary picking mechanism, wherein the clamping mechanism is arranged on the right side of an outer ring of the sampling needle drum, the pushing-pulling shaft is movably clamped in aninner cavity of the sampling needle drum, the secondary picking mechanism is arranged in the middle of the left side of the sampling needle drum, and the sampling mechanism is installed on the left side of the secondary picking mechanism; the clamping mechanism comprises a rotating ring, an extending piece and an arc clamping plate; the sampling mechanism comprises a conical block, a containing groove, a first cutoff ring, a center shaft and a strong spring, the left side of the first cutoff ring is fixedly connected with the an outer ring of the right side of the conical block, and the leftside of the center shaft is fixedly welded to the center of the inner wall of the containing groove. The end inserted into the human body of the puncturing sampling device for medical oncology is designed through a closed solid, during needle inserting, the pain feeling is reduced, and compared with a hollow needle, it can be avoided that redundant tissue is sampled during needle inserting throughthe puncturing sampling device.

The invention relates to a school bus safe shuttling system. The school bus safe shuttling system comprises a vehicle-mounted data processor; the school bus safe shuttling system further comprises a pre-stored person information processing module, an on-board person information processing module, a shuttling person information processing module and an information feedback module; the pre-stored person information processing module mainly comprises a pre-stored person information reading device; the on-board person information processing module mainly comprises an on-board person information reading device; the shuttling person information processing module mainly comprises a shuttling person information reading device; the pre-stored person information reading device, the on-board person information reading device and the shuttling person information reading device are in downlink connection with a data comparison processor; the data comparison processor is in downlink connection with the vehicle-mounted data processor; the information feedback module mainly comprises a display screen device, a printing device, an alarm device and a monitoring device; and the display screen device, the printing device, the alarm device and the monitoring device are all directly connected with the vehicle-mounted data processor.

The invention discloses a soil sampling device for land pollution detection and a using method thereof. The soil sampling device comprises a supporting base, a handle is fixedly installed in the middle of the front portion of the supporting base, turnover mechanisms are arranged on the two sides of the supporting base correspondingly, and a depth sampling mechanism is arranged in the middle of theinner side of the supporting base; the depth sampling mechanism comprises a sampling cylinder, a fixing piece, a motor, a rotating shaft, spiral blades, a discharging pipe, a connecting piece and a drill bit; and a material receiving mechanism is arranged on one side of the upper part of the supporting base. According to the soil sampling device for land pollution detection, on the one hand, thedevice cost is reduced, the structure is simple; on the other hand, the operation convenience is improved, the use effect is improved. Besides, soil samples with different depths can be conveniently collected, the sample collection effect is greatly improved, the practicability is higher, and in addition, the practicability is higher. In addition, material receiving becomes convenient; the collected samples can be conveniently taken out, and the material receiving barrel is very convenient and rapid to mount and dismount.

The invention discloses a storage cabinet for smart home. The storage cabinet for the smart home comprises a base, a cabinet body and storage plates; the cabinet body is fixedly installed on the top of the base, bearings are correspondingly arranged in the middle of the top end of the inner part of the cabinet body and in the middle of the bottom end of the inner part of the cabinet body, the inner part of the cabinet body is movably provided with a rotating shaft through the two bearings, the number of the storage plates is three, the three storage plates are installed on the rotating shaft at equal intervals, one end of the inner part of the base is fixedly provided with a suction fan, one side of the suction fan is fixedly provided with a filter box, the side wall of the side, close to the filter box, of the suction fan is fixedly provided with an air inlet pipe, the suction fan is in mutual communication with the filter box through the air inlet pipe, and the side wall of the side, away from the suction fan, of the filter box is fixedly provided with an air suction pipe. According to the storage cabinet for smart home, by arranging a series of structures, the storage cabinet for smart home has the characteristics of convenient movement and good object-storage effect.

The invention discloses a grid selling cabinet. The grid selling cabinet comprises a server and a cabinet body, wherein the bottom of the cabinet body is provided with a base, the cabinet body is provided with a power module, a main controller, a wireless communication device, a display screen and a plurality of grid bodies, and the front end of each grid body is hinged with a grid door; the innerupper end of each grid body is provided with an electric control lock and a door lock control unit; the upper end of each grid door is provided with a locking cavity cooperating with the corresponding electric control lock; the outer surfaces of at least one grid doors are provided with payment two-dimensional codes; the main controller is connected to the power module, the display screen and door lock control units separately; the main controller is connected to the server through the wireless communication device. The grid selling cabinet has the advantages that the structure is simple, thecost is low, and unmanned retail can be achieved.

The invention relates to a mobile phone internal support plate appearance visual inspection device which is provided with a rack and a working platform, the working platform is provided with a feeding station, a detection station, a carrying station and a discharging station, the feeding station is provided with two feeding mechanisms which are oppositely arranged, the detection station is provided with a first detection mechanism and two oppositely-arranged second detection mechanisms, the carrying station is provided with two oppositely-arranged carrying mechanisms, the discharging station is provided with two oppositely-arranged discharging mechanisms, and the feeding mechanisms are in one-to-one correspondence with the carrying mechanisms and the discharging mechanisms; and the support plates on all the feeding mechanisms are transferred to the first detection mechanisms through the corresponding carrying mechanisms, the support plates are transferred to the corresponding second detection mechanisms through the corresponding carrying mechanisms to be detected after detection is completed, and the support plates are carried to the corresponding discharging mechanisms to be distributed and discharged after detection is completed. The device can realize comprehensive, rapid and accurate detection of the support plate, and is efficient and practical.

The invention provides a pneumatic butterfly valve which comprises a valve body, wherein a valve rod is arranged in the valve body in a penetrating manner; the upper end of the valve rod is exposed tothe external part of the valve body; a valve is arranged in the middle of the valve rod; the pneumatic butterfly valve is characterized in that the upper end of the valve rod is positioned in a bracket; the valve body and a cylinder are connected and fixed with the bracket; the upper end of the valve body is connected with a connecting block in the bracket; a gear output shaft is arranged in thecylinder and is connected with the connecting block; two rack pistons are symmetrically arranged on the two sides of the gear output shaft; the gear on the gear output shaft is meshed with the racks of the two rack pistons; the two rack pistons do straight reciprocating motion through air source pressure; and the rack pistons drive the gear output shaft to rotate during the moving process. The pneumatic butterfly valve adopts the air as the power source to control the butterfly valve to be automatically closed and opened, so that the error is reduced. In addition, the air has the advantages ofbeing convenient to collect and free of pollution, is suitable for being used in the anti-explosion and flame-proof field and has wide application prospect in the service field.

The invention discloses a detection system for the continuous detection of the molten steel temperature and the composition for converter steelmaking, and relates to the technical field of steelmakingdetection equipment. By arranging a seating brick and a probe conveying pipe on the side wall of a converter, probes of various types are arranged in different detection through holes in the probe conveying pipe respectively, the molten steel temperature, the molten steel oxygen activity, and the low carbon and phosphorus content in the molten steel in the converter can be detected in real time,and an operator conveniently takes the corresponding operational means to reach the smelting end point in an optimized manner so as to improve various economic and technical indexes in steelmaking.

The invention discloses a self-adaptive bookshelf, relates to the technical field of hardware equipment for libraries, and in particular to a bookshelf device. The self-adaptive bookshelf comprises a bookshelf main body frame, wherein rectangular hollow frames are arranged on the front and back sides of the main body frame; rectangular panels are arranged on the left and right sides of the main body frame; a bearing plate is arranged at the lower end of the main body frame; rubber raised lines are uniformly distributed on the upper surface of the bearing plate; a self-adaptive window is arranged at the upper end of the main body frame; at least two cross shafts are mounted in the self-adaptive window; a row of vertical baffle strips which are arranged in parallel are connected to each cross shaft through a rotating shaft; the rear end part of each vertical baffle strip is connected with each cross shaft through the rotating shaft; lower surfaces of the vertical baffle strips are concave cambered surfaces. The self-adaptive bookshelf is smart in structure and is convenient to use, and books do not affect each other.