With the rapid development of urban building automation, the safe, comfortable and intelligent living environment has gradually become the basic requirement of modern intelligent buildings, and the intercom system has become an important part of the demand. In response to this growing demand, the demand for visual and non-visual engineering design information from the intelligent building intercom system is particularly high. As far as the design and application of smart building intercom systems are concerned, there is no principle and it is particularly prone to problems. Therefore, the author takes this article to explore advanced security with you and hopes to obtain advanced guidance and feedback from the industry.
Intelligent Building Talkback System Engineering Features
The intelligent building intercom system is an intelligent system of visitor identification and access control electronic control plus information management integrated with the single chip microcomputer technology, duplex intercom technology, CCD camera and video imaging technology. Access to building entrances and exits is generally in a locked state to prevent non-individuals from entering the building without permission. Residents in the building can access the door with a card or a key or a password. When a guest visits, press the room number of the interviewed user on the intercom host keypad outside the downstairs or main entrance, call the intercom extension of the interviewed household, and connect with the owner of the visited household after connecting. Call or video call. After confirming the identity of the visitor through dialogues or images, the owner of the household allows the visitor to enter, and then use the unlock button on the extension to open the electric lock on the entrance to the building so that visitors can enter the building. When the visitor arrives, the door is automatically locked. There are differences in the use of the system and architecture or equipment deployment between the system and the community smart intercom system. Of course, there are some differences in the design and application.
Relative to the past, the intercom system of the smart community is neither digital nor the so-called integrated integration work. Many engineering personnel are not very familiar with some basic concepts. There is not much understanding of the digitalization of smart building intercom systems. Basically, they all adopt the traditional bus architecture. Therefore, the information on the design and construction of some smart building intercoms is not very complete. The author will start with this section.
Intelligent building intercom system host design points
In the intelligent building intercom system components and construction content, the door machine is installed at the entrance of the building security door. It includes an operation panel, a bottom box, a camera, and a voice signal and control section. In the construction project, there is an anchoring of the bottom box, the assembly of the panel, and the connection of the circuit. The most important tasks are the adjustment of the image and the correction of the light difference between day and night. In addition, because of the need to cooperate with the residential structure, it may be necessary to cooperate with civil engineering projects in the application. Its purpose is mainly to avoid the bottom box extrusion deformation and the perfect panel fixing. The project installed on the door machine also includes a sound receiving and sending part. In the case of application, attention should be paid to the sound pressure and the height of the horn collector installed, in order to suit the average height of the average user.
In the video part of the door machine, due to the limited depth of field of most installation points, most of the cameras adopt the board type, so the performance of the camera is slightly worse than that of the general surveillance camera, and the quality and resolution are not High, and most of them lack the performance of backlight correction, so there are some entrance door opportunities to install infrared light or white light to strengthen the image, these conditions require that the intercom door machine in the installation of some special engineering adjustment projects must Execution, this must be paid attention to in the intelligent building intercom system.
Intelligent building intercom transmission and networking cabling technology
As smart building intercom systems are gradually moving towards digital applications, many engineering companies must integrate the access control systems of various brands into the door-to-door and system cabling integration. Therefore, the networking of the system must take into account the interconnection of the intercom and the access control system. Line layout and signal transmission. The design of the network integrated cabling project has a decisive influence on the process of wiring the intelligent building intercom system, and should be carried out with caution in construction design and installation projects. Usually, after the construction planning of the intelligent building intercom system is completed, the next step is the installation and implementation of the project. The most important task before construction is the project preparation work. These tasks and precautions include the following.
1, master and fully understand the wiring construction drawings, determine the location of the wiring, need to consider such as aesthetics and concealment, the destruction of the building must be reduced to a minimum, in the cloth to avoid power lines and other communication lines to avoid interference and string In the case of information, at the same time, necessary protection measures must be taken for the cables. At the same time, it is necessary to assess the feasibility of installation and wiring before installation, especially for projects such as wall piers and trussed columns, and then hand them over when feasible. And so on, construction personnel, supervisors and supervisors perform.
2, careful calculation of material requirements, in the final worksheet to do a good job in calculation of materials and labor, comprehensive consideration of the design and implementation of the management operations and other costs proposed budget and duration and construction programs and arrangements. The degree of cooperation of the user needs to be considered in the implementation plan. The implementation plan needs to negotiate the approval signature with the user and specify the coordinating responsible person to designate the person in charge of the project and the project supervision personnel to be responsible for planning the preparation of materials, preparation of the work, and the user's request for cooperation.
3. Intelligent building intercom network engineering requires many construction materials in the construction process. Some of these materials must be prepared before starting work, and some can be stocked during the start-up process. These materials mainly include optical cables, UTP twisted pairs, and RJ. Sockets, signal control modules, servers, power supplies, HUB hubs, etc., and determine the date of delivery, different specifications of PVC fire protection pipe, winding pipe, screws and other materials in place, will do a good job construction equipment and equipment safety measures , Formulate construction schedule.
4, planning and design of intercom system should first pay attention to specification standards. The design of the wiring must be done to meet the needs of the users, and at the same time, the construction cost must be met. Strict standards have clear rules for the structured cabling system to achieve engineering requirements and technical pointers.
5, intelligent building intercom system must be based on the actual situation. The layout of the layout of the design in addition to the direct impact on the construction costs, but also related to whether the network cabling is reasonable, for a multi-storey building, the installation of the entire building network backbone switch information center network room, preferably installed in the building In the middle floor, if the wiring closet is set on each floor, it is better to set it on the middle section of the floor. This design can not only shorten the wiring length of vertical and horizontal trunk subsystems, save materials, reduce costs, but also reduce unnecessary channel transmission. Distance and material waste.
6. It is necessary to promptly deal with all kinds of situations that occur during the construction process and coordinate the opinions of all parties. If on-site construction encounters unforeseen problems, it shall promptly report to the engineering unit Yuanyuan and propose solutions for the engineering unit yuan. Study and solve the problem on the spot so as not to affect the progress of the project.
Intelligent building intercom equipment installation planning details
Intelligent building intercom system equipment installation, you must consider all kinds of installation problems may occur, these specific problems are very large, many types, construction must be one by one to understand their details, look at the host part (including the host of the door, Enclosure door host, household indoor host) It should be noted that there are mainly the following points: The equipment must not be exposed to wind and rain, if not, please add rain cover; the door machine should not face the camera lens or direct traffic in the intersection Sunlight or strong light; using fill light measures, try to keep the background light in front of the camera in front of the camera in the same average; avoid the motor of the electric roll door or do not install near the strong magnetic field; the line wiring should be considered at the entrance of the host Drip line; color camera should consider the need for nighttime visible light compensation; do not install in outdoor environment noise noise greater than 70dB; the indoor unit should not face the display light, LCD color display should pay attention to light reflection and monitoring angle. Do not install in high-temperature heating lines, air conditioning, low temperatures, excessive dust or serious pollution.
Intelligent building intercom system design using FAQ
Intelligent building intercom systems often lead to obvious advantages and disadvantages in the construction quality and use of intelligent building intercom systems due to the complex characteristics of wiring and system linkage. The main causes of these problems include: product quality problems, construction installation and debugging problems, and follow-up. Maintenance and use of operating habits and environmental issues and other factors. Coupled with the alarm monitoring system and building intercom systems are often tied together, so there is a close relationship between the number of lines and power supply.
Intelligent building intercom is a more complex system engineering. The system design, product selection, project implementation and system maintenance all affect the stable operation of the system. Therefore, when a problem occurs in the system, it should first analyze the key point that caused the problem, and then determine the responsibility. Arbitrary judgment responsibility is equipment manufacturer or engineering integrator, which is irrational in engineering.
According to engineering experience, the reason for the high rate of “bad operation†of smart building intercom systems is mainly due to the fact that the application environment is mainly based on the smart community public intercom system combined with the perimeter alarm prevention system. Therefore, the mutual influence factors are high and construction must Pay attention to the working status of each system. Next, from the perspective of system construction, the higher the degree of system integration, the higher the rate of "bad" systems; the system involves too many operating systems or too many integrated product brands, and the "negligible rate" is higher; the space distribution of smart building intercom systems With a wide range and long transmission distance, the "negative rate of establishment" is also higher.
In contrast, smart building intercom systems are better known and of better quality than most corporate branding applications, and metropolitan-grade intercom monitoring and alarm systems are also better than smaller cities. Security system engineering quality in both China and the region. Therefore, most of the building intercom systems have the following problems.
1, the product quality varies from one brand to another, and fake copycats emerge one after another. The more developed the intercom industry, more and more people have joined the security industry. Many manufacturers start assembling security security products under simple manpower and equipment. The low cost of products is not high, but they are not formal industrial structures. The intelligent building intercom system is a highly professional product that requires high input costs and a long recycling period. It has high requirements for technology, experience and maintenance.
However, a large number of low-cost technology companies influx, the industry hides a huge risk: First, the market risk, the market will inevitably stand upright, a large number of professional firms that have lost professional standards are facing elimination, resulting in product after-sales service can not keep up; Still a user. The second is social risks. Intercom product companies with low-cost and quality standards can not only provide qualified building intercom products for cities and residents, but may instead be a large number of safety hazard systems.
It is also through the same testing agency to test qualified products from different manufacturers. In the actual use process, there is still a great difference in performance. The qualified inspection only represents that the product can be used in the market, and it does not mean that the product will not have quality problems. And there will be differences between the products submitted for inspection and the products actually mass produced; at the same time, there will be differences in the use of components in different batches of products, resulting in the quality of finished products.
2. Inadequate installation and design of the system construction result in poor system performance. The main reasons for the analysis of poor engineering in smart building intercom systems include improper construction design. First, the smart building intercom system is designed to be installed in an open air space without waterproof or moisture-proof treatment, causing the equipment to cause water failure. The second is to design the door machine on the door, because when the door is opened and closed, it will bring vibrations to the door machine and cause poor contact failure. Thirdly, it will cause the networked equipment to be installed outdoors, resulting in the presence or absence of waterproof treatment and lightning protection. Faults; Fourth, poor line construction does not, resulting in a failure, the entire building vacant system shut down; five is to cut down the installation of power and load power shortage, resulting in unstable power supply, image distortion jitter failure; Six is ​​not using the original power supply The unstable operation is caused. Seventhly, the door lock is improperly designed, which results in door element failure caused by door panel deformation or poor quality of the electric lock.
All kinds of failures mentioned above, users and property management companies cannot grasp this link, but can only attribute their responsibilities to the problems of smart building intercom products and poor construction quality. In addition, the construction process is rough: For example, there is no proper stainless steel screw, no wiring, no welding, and no insulated heat shrinkable tubing. In particular, after the copper wires are twisted together, only the electric tape is wound in disorder. This situation is not much, this is caused by loose wiring, disconnection or poor contact, spark interference and wiring oxidation.
In addition, it is caused by natural factors; equipment is not clean and maintained, there is no routine inspection, corrosion caused by dust, insects, rodents, rat urine, etc., and non-human failure. For example, some tiger insects crawl into floor platforms, power supplies, extensions, and mainframes during the winter. This type of equipment will generate tiny heat during work, allowing insects to warm over the winter, causing circuit board short circuits and equipment failure.
3, system use error and frequency of use is too high. In general, intelligent building intercom systems do not stop running for 24 hours. In particular, the commercial building intercom system is used at a particularly high frequency, and is also relatively prone to failure; on the other hand, during the installation of the system after the wrong operation, The system may have these problems due to improper operation or use of personnel to arbitrarily modify the system configuration, causing illegal operations or non-maintenance personnel to log in to operate the system.
4. The construction of transmission lines is of different quality. Smart building intercom products, including mainframes, extensions, floor exchanges, and networked switches, are the key to the stability of the product's core technology and quality system. The transmission part of the system's wire and wiring is the absolute key to the merits of the system. At present, most of the building intercom products use the traditional video line plus signal line method. Not only is the wire cost higher and the construction is more troublesome, it is easily disturbed by environmental factors in the transmission process and affects the stability of the system. The network is the networking core of the entire digital building intercom system. The stability of network digital networking performance is the greatest demand for the stability of building intercom systems. Especially in the building networking of large buildings, the networking core technology has an important influence on the stability of the entire intelligent building intercom system.
5, not according to the provisions of project acceptance. Even if the smart building intercom has passed the acceptance test, it will generally be relatively stable after the new system has been installed and debugged. Since it has not yet undergone the test of harsh environments, it is difficult to find the hidden problems in construction, especially the wiring project. In the outdoor environment, after the system has been frequently used every day through wind and rain showers, solar baptism, and intelligent building intercom systems, problems will gradually emerge.
All these are explanations of the intelligent building intercom system in the solution of engineering design problems. They are all very important rules of thumb in the engineering practice of intelligent building intercom systems. Only those solutions that can remember these problems can avoid bad engineering. happened.
Intelligent Building Talkback System Engineering Features
The intelligent building intercom system is an intelligent system of visitor identification and access control electronic control plus information management integrated with the single chip microcomputer technology, duplex intercom technology, CCD camera and video imaging technology. Access to building entrances and exits is generally in a locked state to prevent non-individuals from entering the building without permission. Residents in the building can access the door with a card or a key or a password. When a guest visits, press the room number of the interviewed user on the intercom host keypad outside the downstairs or main entrance, call the intercom extension of the interviewed household, and connect with the owner of the visited household after connecting. Call or video call. After confirming the identity of the visitor through dialogues or images, the owner of the household allows the visitor to enter, and then use the unlock button on the extension to open the electric lock on the entrance to the building so that visitors can enter the building. When the visitor arrives, the door is automatically locked. There are differences in the use of the system and architecture or equipment deployment between the system and the community smart intercom system. Of course, there are some differences in the design and application.
Relative to the past, the intercom system of the smart community is neither digital nor the so-called integrated integration work. Many engineering personnel are not very familiar with some basic concepts. There is not much understanding of the digitalization of smart building intercom systems. Basically, they all adopt the traditional bus architecture. Therefore, the information on the design and construction of some smart building intercoms is not very complete. The author will start with this section.
Intelligent building intercom system host design points
In the intelligent building intercom system components and construction content, the door machine is installed at the entrance of the building security door. It includes an operation panel, a bottom box, a camera, and a voice signal and control section. In the construction project, there is an anchoring of the bottom box, the assembly of the panel, and the connection of the circuit. The most important tasks are the adjustment of the image and the correction of the light difference between day and night. In addition, because of the need to cooperate with the residential structure, it may be necessary to cooperate with civil engineering projects in the application. Its purpose is mainly to avoid the bottom box extrusion deformation and the perfect panel fixing. The project installed on the door machine also includes a sound receiving and sending part. In the case of application, attention should be paid to the sound pressure and the height of the horn collector installed, in order to suit the average height of the average user.
In the video part of the door machine, due to the limited depth of field of most installation points, most of the cameras adopt the board type, so the performance of the camera is slightly worse than that of the general surveillance camera, and the quality and resolution are not High, and most of them lack the performance of backlight correction, so there are some entrance door opportunities to install infrared light or white light to strengthen the image, these conditions require that the intercom door machine in the installation of some special engineering adjustment projects must Execution, this must be paid attention to in the intelligent building intercom system.
Intelligent building intercom transmission and networking cabling technology
As smart building intercom systems are gradually moving towards digital applications, many engineering companies must integrate the access control systems of various brands into the door-to-door and system cabling integration. Therefore, the networking of the system must take into account the interconnection of the intercom and the access control system. Line layout and signal transmission. The design of the network integrated cabling project has a decisive influence on the process of wiring the intelligent building intercom system, and should be carried out with caution in construction design and installation projects. Usually, after the construction planning of the intelligent building intercom system is completed, the next step is the installation and implementation of the project. The most important task before construction is the project preparation work. These tasks and precautions include the following.
1, master and fully understand the wiring construction drawings, determine the location of the wiring, need to consider such as aesthetics and concealment, the destruction of the building must be reduced to a minimum, in the cloth to avoid power lines and other communication lines to avoid interference and string In the case of information, at the same time, necessary protection measures must be taken for the cables. At the same time, it is necessary to assess the feasibility of installation and wiring before installation, especially for projects such as wall piers and trussed columns, and then hand them over when feasible. And so on, construction personnel, supervisors and supervisors perform.
2, careful calculation of material requirements, in the final worksheet to do a good job in calculation of materials and labor, comprehensive consideration of the design and implementation of the management operations and other costs proposed budget and duration and construction programs and arrangements. The degree of cooperation of the user needs to be considered in the implementation plan. The implementation plan needs to negotiate the approval signature with the user and specify the coordinating responsible person to designate the person in charge of the project and the project supervision personnel to be responsible for planning the preparation of materials, preparation of the work, and the user's request for cooperation.
3. Intelligent building intercom network engineering requires many construction materials in the construction process. Some of these materials must be prepared before starting work, and some can be stocked during the start-up process. These materials mainly include optical cables, UTP twisted pairs, and RJ. Sockets, signal control modules, servers, power supplies, HUB hubs, etc., and determine the date of delivery, different specifications of PVC fire protection pipe, winding pipe, screws and other materials in place, will do a good job construction equipment and equipment safety measures , Formulate construction schedule.
4, planning and design of intercom system should first pay attention to specification standards. The design of the wiring must be done to meet the needs of the users, and at the same time, the construction cost must be met. Strict standards have clear rules for the structured cabling system to achieve engineering requirements and technical pointers.
5, intelligent building intercom system must be based on the actual situation. The layout of the layout of the design in addition to the direct impact on the construction costs, but also related to whether the network cabling is reasonable, for a multi-storey building, the installation of the entire building network backbone switch information center network room, preferably installed in the building In the middle floor, if the wiring closet is set on each floor, it is better to set it on the middle section of the floor. This design can not only shorten the wiring length of vertical and horizontal trunk subsystems, save materials, reduce costs, but also reduce unnecessary channel transmission. Distance and material waste.
6. It is necessary to promptly deal with all kinds of situations that occur during the construction process and coordinate the opinions of all parties. If on-site construction encounters unforeseen problems, it shall promptly report to the engineering unit Yuanyuan and propose solutions for the engineering unit yuan. Study and solve the problem on the spot so as not to affect the progress of the project.
Intelligent building intercom equipment installation planning details
Intelligent building intercom system equipment installation, you must consider all kinds of installation problems may occur, these specific problems are very large, many types, construction must be one by one to understand their details, look at the host part (including the host of the door, Enclosure door host, household indoor host) It should be noted that there are mainly the following points: The equipment must not be exposed to wind and rain, if not, please add rain cover; the door machine should not face the camera lens or direct traffic in the intersection Sunlight or strong light; using fill light measures, try to keep the background light in front of the camera in front of the camera in the same average; avoid the motor of the electric roll door or do not install near the strong magnetic field; the line wiring should be considered at the entrance of the host Drip line; color camera should consider the need for nighttime visible light compensation; do not install in outdoor environment noise noise greater than 70dB; the indoor unit should not face the display light, LCD color display should pay attention to light reflection and monitoring angle. Do not install in high-temperature heating lines, air conditioning, low temperatures, excessive dust or serious pollution.
Intelligent building intercom system design using FAQ
Intelligent building intercom systems often lead to obvious advantages and disadvantages in the construction quality and use of intelligent building intercom systems due to the complex characteristics of wiring and system linkage. The main causes of these problems include: product quality problems, construction installation and debugging problems, and follow-up. Maintenance and use of operating habits and environmental issues and other factors. Coupled with the alarm monitoring system and building intercom systems are often tied together, so there is a close relationship between the number of lines and power supply.
Intelligent building intercom is a more complex system engineering. The system design, product selection, project implementation and system maintenance all affect the stable operation of the system. Therefore, when a problem occurs in the system, it should first analyze the key point that caused the problem, and then determine the responsibility. Arbitrary judgment responsibility is equipment manufacturer or engineering integrator, which is irrational in engineering.
According to engineering experience, the reason for the high rate of “bad operation†of smart building intercom systems is mainly due to the fact that the application environment is mainly based on the smart community public intercom system combined with the perimeter alarm prevention system. Therefore, the mutual influence factors are high and construction must Pay attention to the working status of each system. Next, from the perspective of system construction, the higher the degree of system integration, the higher the rate of "bad" systems; the system involves too many operating systems or too many integrated product brands, and the "negligible rate" is higher; the space distribution of smart building intercom systems With a wide range and long transmission distance, the "negative rate of establishment" is also higher.
In contrast, smart building intercom systems are better known and of better quality than most corporate branding applications, and metropolitan-grade intercom monitoring and alarm systems are also better than smaller cities. Security system engineering quality in both China and the region. Therefore, most of the building intercom systems have the following problems.
1, the product quality varies from one brand to another, and fake copycats emerge one after another. The more developed the intercom industry, more and more people have joined the security industry. Many manufacturers start assembling security security products under simple manpower and equipment. The low cost of products is not high, but they are not formal industrial structures. The intelligent building intercom system is a highly professional product that requires high input costs and a long recycling period. It has high requirements for technology, experience and maintenance.
However, a large number of low-cost technology companies influx, the industry hides a huge risk: First, the market risk, the market will inevitably stand upright, a large number of professional firms that have lost professional standards are facing elimination, resulting in product after-sales service can not keep up; Still a user. The second is social risks. Intercom product companies with low-cost and quality standards can not only provide qualified building intercom products for cities and residents, but may instead be a large number of safety hazard systems.
It is also through the same testing agency to test qualified products from different manufacturers. In the actual use process, there is still a great difference in performance. The qualified inspection only represents that the product can be used in the market, and it does not mean that the product will not have quality problems. And there will be differences between the products submitted for inspection and the products actually mass produced; at the same time, there will be differences in the use of components in different batches of products, resulting in the quality of finished products.
2. Inadequate installation and design of the system construction result in poor system performance. The main reasons for the analysis of poor engineering in smart building intercom systems include improper construction design. First, the smart building intercom system is designed to be installed in an open air space without waterproof or moisture-proof treatment, causing the equipment to cause water failure. The second is to design the door machine on the door, because when the door is opened and closed, it will bring vibrations to the door machine and cause poor contact failure. Thirdly, it will cause the networked equipment to be installed outdoors, resulting in the presence or absence of waterproof treatment and lightning protection. Faults; Fourth, poor line construction does not, resulting in a failure, the entire building vacant system shut down; five is to cut down the installation of power and load power shortage, resulting in unstable power supply, image distortion jitter failure; Six is ​​not using the original power supply The unstable operation is caused. Seventhly, the door lock is improperly designed, which results in door element failure caused by door panel deformation or poor quality of the electric lock.
All kinds of failures mentioned above, users and property management companies cannot grasp this link, but can only attribute their responsibilities to the problems of smart building intercom products and poor construction quality. In addition, the construction process is rough: For example, there is no proper stainless steel screw, no wiring, no welding, and no insulated heat shrinkable tubing. In particular, after the copper wires are twisted together, only the electric tape is wound in disorder. This situation is not much, this is caused by loose wiring, disconnection or poor contact, spark interference and wiring oxidation.
In addition, it is caused by natural factors; equipment is not clean and maintained, there is no routine inspection, corrosion caused by dust, insects, rodents, rat urine, etc., and non-human failure. For example, some tiger insects crawl into floor platforms, power supplies, extensions, and mainframes during the winter. This type of equipment will generate tiny heat during work, allowing insects to warm over the winter, causing circuit board short circuits and equipment failure.
3, system use error and frequency of use is too high. In general, intelligent building intercom systems do not stop running for 24 hours. In particular, the commercial building intercom system is used at a particularly high frequency, and is also relatively prone to failure; on the other hand, during the installation of the system after the wrong operation, The system may have these problems due to improper operation or use of personnel to arbitrarily modify the system configuration, causing illegal operations or non-maintenance personnel to log in to operate the system.
4. The construction of transmission lines is of different quality. Smart building intercom products, including mainframes, extensions, floor exchanges, and networked switches, are the key to the stability of the product's core technology and quality system. The transmission part of the system's wire and wiring is the absolute key to the merits of the system. At present, most of the building intercom products use the traditional video line plus signal line method. Not only is the wire cost higher and the construction is more troublesome, it is easily disturbed by environmental factors in the transmission process and affects the stability of the system. The network is the networking core of the entire digital building intercom system. The stability of network digital networking performance is the greatest demand for the stability of building intercom systems. Especially in the building networking of large buildings, the networking core technology has an important influence on the stability of the entire intelligent building intercom system.
5, not according to the provisions of project acceptance. Even if the smart building intercom has passed the acceptance test, it will generally be relatively stable after the new system has been installed and debugged. Since it has not yet undergone the test of harsh environments, it is difficult to find the hidden problems in construction, especially the wiring project. In the outdoor environment, after the system has been frequently used every day through wind and rain showers, solar baptism, and intelligent building intercom systems, problems will gradually emerge.
All these are explanations of the intelligent building intercom system in the solution of engineering design problems. They are all very important rules of thumb in the engineering practice of intelligent building intercom systems. Only those solutions that can remember these problems can avoid bad engineering. happened.
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