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1、A Novel Structure of Intelligent Network Control SystemInspired from Neuroendocrine-Immune System1Liu Bao1*，Ding Yongsheng2*，Wang Junhong11 College of Information and Control Engineering，China University of Petroleum，Dongying，Shandong（257061）2 College of Information Sciences and Technology, Donghua
2、University，Shanghai（201620）E-mail：，，AbstractBased on the modulation mechanism of neuroendocrine-immune (NEI) system, we present a noveldistributed bio-network control system (DBNCS). The DBNCS includes four levels. The first level is corresponding to immune system, and is composed of some embedded t
3、ransmitter-controller units (ETCU), which are designed based on the ultra-short loop feedback mechanism of NEI. Every ETCU can be regarded as an agent with intelligence of self-awareness, self-organization, and self-reconfiguration. The second level is corresponding to endocrine system, and is compo
4、sed of several agent-based work stations. The agents in the second level, regarded as endocrine glands, are responsible for coordinating the control activity of field-agents in the first level. The third level and fourth level are corresponding to central nervous system. The third level is composed
5、of Web server and several manage servers, and provides Web service that accesses to all the entities in the DBNCS. The manage server, noted as lead-agent, manages all the agents in the first level and the second level. The fourth level is composed of some remote computers on Internet. The operators
6、and engineers can monitor the process and the state of all the entities in DBNCS, and adjust the control parameters remotely. The DBNCS has several characteristics, i.e. entire harmony, bi-regulation, complicated feedback, no-delay field-control, and remote network optimization. The DBNCS provides a
7、 novel method for the study on Internet-based network control system.Keywords: neuroendocrine-immune, network control, distributed control1IntroductionSince 1970s, the first generation network control system (NCS), i.e. distributed control system (DCS), has been developed 1. During the middle of 199
8、0s, filed-bus control system (FCS) was appeared 2. And the third generation NCS based on the Ethernet and Internet, noted as ECS or ICS, has been reported since the end of 1990s 3. The development of FCS is restricted for the exit ofseveral field-bus criterions, i.e. FF H1, Control Net, PROFIBUS, HS
9、E, etc, which are not compatible with each other 4. So it is very important to develop the third generation NCS with a uniform protocol, TCP/IP. Until now, there are two kinds of ECS, i.e. mixed and uniform type 5. For the former, the field-bus is still selected in field level and TCP/IP protocol is
10、 selected for other high levels; for the later, TCP/IP protocol is selected for all levels. In fact, many successful application cases about the former type have been reported. But the successful application on the uniform type ECS is still limited to the remote monitoring of process 6. The key prob
11、lem is the delay-time in this type ECS is stochastic or not limited. With the development of the computer, embedded and agent technologies have been applied 5-6. However, there are few NCS reports inspired from bio-systems.As well known, nervous system, endocrine system, and immune system are three
12、important physiological modulation systems in body 7-10. Nervous system detects the inner and outside state to regulate the function of all the apparatus in body. Endocrine system secretes some kinds of hormone to adjust the metabolism. And immune system is responsible for eliminating the invaded fo
13、reign antigen. These three systems compose the neuroendocrine-immune (NEI) network. On the whole, the NEI network is a complicated physiological system and has some special modulation1 Support by the Doctoral Fund for Youth Teachers of Ministry of Education of China (No. 20070425518).-6-mechanism 11
14、-13. These three systems can keep the homeostatic very stable in body via their harmonious control. The study on the artificial NEI system may inspire some novel methods to solve some complicated problems of NCS. Corresponding to NCS, nervous system, endocrine system, and immune system may be regard
15、ed as optimized level, coordinative level, and executive level, respectively.Based on the regulation mechanism of NEI, we present a novel distributed bio-network control system (DBNCS). The DBNCS includes four levels. Level 1 is corresponding to immune system, and is composed of some embedded transm
16、itter-controller units (ETCU), which are designed based on the ultra-short loop feedback mechanism of NEI. Every ETCU can be regarded as an agent with intelligenceofself-awareness,self-organization,andself-reconfiguration.Level2is corresponding to endocrine system, and is composed of several agent-b
17、ased work stations. The agents in level 2, regarded as endocrine glands, are responsible for coordinating the control activity of field-agents in level 1. Level 3 and 4 are corresponding to central nervous system. Level 3 is composed of Web server and several manage servers, and provides Web service
18、 that accesses to all the entities in the DBNCS. The manage server noted as group-agent manages all the agents in level1 and 2. Level 4 is composed of some remote computers on Internet. The operators and engineers can monitor the process and the state of all the entities in DBNCS, and adjust the con
19、trol parameters remotely. The DBNCS has several characteristics, i.e. entire harmony, bi-regulation, complicated feedback, no-delay field-control, and remote network optimization. The DBNCS provides a novel method for the study on Internet-based NCS.This paper is organized as follows. The regulation
20、 mechanism of NEI system is first briefly introduced in Section 2. Next, the structure and characteristics of the DBNCS are explained in Section 3. Finally, the concluding remarks are given in the last section.2Regulation Mechanism of Neuroenodocrine-Immune NetworkAs well known, nervous system, endo
21、crine system, and immune system are three important physiological modulation systems in body 7-10. Nervous system detects the inner and outside state to regulate the function of all the apparatus in body. Endocrine system secretes some kinds of hormone to adjust the metabolism. And immune system is
22、responsible for eliminating the invaded foreign antigen. These three systems compose the NEI system. On the whole, the NEI system is a complicated physiological system with some special modulation mechanisms 11-13.2.1Regulation mechanism of hormoneThe regulation mechanism of hormone is similar to th
23、e closed-loop feedback control theory. First, central nervous system makes hypothalamo secrete trophic hormone (TH), which stimulates the pituitary to secrete releasing-hormone (RH). Then RH stimulates the corresponded grand to secret hormone. Here, the TH and RH are generic terms of several kinds h
24、ormone, respectively. In the modulation system, there are at least four types of feedback, which include ultra-short loop feedback, short loop feedback, long loop feedback, and ultra-long loop feedback, as shown in Fig.1. For example, the ultra-short loop feedback means the concentration of TH is fe
25、d back to hypothalamo, that of RH is fed back to pituitary, and that of hormone is fed back to grand. The short loop feedback means the concentration of TH is fed back to central nervous system, the concentration of RH is fed back to hypothalamo, and that of hormone is fed back to pituitary. The lon
26、g loop feedback means that the convention of hormone is fed back to hypothalamo, and that of RH is fed back to central nervous system. The ultra-long loop feedback means the concentration of hormones is fed back to central nervous system. Above these feedbacks are all completed via cell-sensors. Thr
27、ough the complicated multiple feedback mechanism, the hormone concentration can be controlled stable easily.2.2Bi-modulation mechanism in NEIBi-modulation is another special mechanism in NEI system. Neuroendocrine system may strengthen or weaken the activity of immune system through different hormon
28、es. For example, some hormones, i.e. adrenocorticotrophic hormone, androgenic hormones, and prostaglandin, etc., can weaken the activity of immune system. While some other hormones, i.e. thyroid hormone, growth hormone, prolactin, etc. can strengthen it. This is the cooperativity of hormones.The cen
29、tral nervous system lies in the highest level, and it can harmoniously regulate the endocrine and immune system. When antigen invades the body, immune system not only tries to eliminate the antigen through the immune response, but also can cause the change of endocrine-immune system to adapt to the
30、immune response. Thus, antigen can be eliminated quickly, and the homeostasis inbody is kept.Central NervousSystemHypothalamusPituitaryGlands- -+HRH+ +RH+Hormones- - - -Ultra-short feedbackShort feedback Long feedbackUltra-long feedbackFigure 1 Regulation Mechanism of Hormones3Bio-Network Control Sy
31、stemCorresponding to NCS, nervous system, endocrine system, and immune system may be regarded as optimized level, coordinative level, and executive level, respectively. These three systems can keep the homeostatic in body stable via their harmonious control. According to Fig. 1, we present a DBNCS.3
32、.1Structure of DBNCSThe DBNCS includes level 1, 2, 3, and 4, as shown in Fig. 2. Level 1 is corresponding to executive level, level 2 is corresponding to coordinative level, and level 3 and 4 are corresponding to optimized level. All the entities in four levels work with TCP/IP protocol.Level 1 is c
33、orresponding to the immune system and is designed based on the ultra-short loop feedback mechanism. This level is composed of many distributed ETCUs, which can execute the task of transmit and control in the industrial field. The ETCU can be located anywhere according to the need of process control.
34、 The operators or engineers can access the ETCU remotely via the Web page, and monitor the process data and modify the control parameters conveniently. In every ETCU, there are two kinds of feedback, i.e. inner and outside feedback. One of inner feedbacks is that the output of controller is fed back
35、 to the controller, corresponding to the ultra-short loop feedback. The other inner feedback is that the process variable, the output of the transmitter, is fed back to thecontroller. The outside feedback includes the information fed back to level 2, 3, and 4. Every ETCUcan be regarded as an agent,
36、which has intelligence of self-awareness, self-organization, andself-reconfiguration.Level 4InternetRemoteControlAB Level 31 2 3Level 2ControlRoomLevel 112 3n-1n ControlFiledProcessECTUECTUSever Web Sever Remote ComputerSwitchEthernetFeedback Short & Ultra-Short FeedbackFigure 2 The structure of the
37、 DBNCSThe agents in this level, noted as field-agents, can work harmoniously to control the process variables stable. The activity of the field-agents is regulated by the group-agents in level 2. Every field-agent can monitor the state of its neighbor agents, track their outputs, and record their pa
38、rameters. If one agent died (maybe hardware or software fault), its neighbors will make an agreement that the one with less load or who first got the news will execute the duty of that died agent immediately.The level 2 is corresponding to endocrine system, and is composed of several agent-based wor
39、k stations. The agents in this level, noted as group-agents, are responsible for coordinating the control activity of field-agents in level 1. Every group-agent can be regarded as an endocrine gland, which secretes hormone to modulate the activity of immune system. According to the control goal, eve
40、ry group-agent may manage several field-agents to complete the task quickly. The information fed back here includes the state of field-agent in level 1, and the process variables. Based on the feedback information and the control commands received from lead-agents in level 3, the group-agents send h
41、armonious signals to their corresponding field-agents in level 1. Here, the harmonious signals, corresponding to hormones, include set point value, control parameters, etc. Inspired form the bi-modulation mechanism, the harmonious signals from a group-agent involves two types: strengthening action a
42、nd weakening action. And the harmonious signals from different group-agents may be cooperative for one or several field-agents. Thus, these signals can realize the modulation process quickly and stably.Level 3 and 4 are corresponding to central nervous system. Level 3 is composed of Web server and s
43、everal manage servers, and provides Web service that can access to all the entities in the DBNCS and manages all the agents in level 1 and 2. The manage server is also an agent, noted as lead-agent, which can optimize the activity of the agents in level 2. The feedback information here includes the
44、harmonious signal form level 2 to level 1, the state of all the agents in level 2 and 1, and the process variables. After analyzing the information, the lead-agents can optimize the activity of all agents in level 2. Thus the activity of field-agents is also optimized. In fact, this is a network-bas
45、ed optimized control structure. Level 3 is also responsible for balancing the load in network and keeping the DBNCS inner stable. Level 4 is composed of some remote computers on Internet. With the firewall,the communication between level 4 and 3 can be safe. The operators and engineers can monitor t
46、he process and the state of all the entities in DBNCS, and adjust the control parameters remotely. The information fed back here includes the state of all the agents in DBNCS and the process data. Level4 is also a remote man-machine interface. The operator or engineers can send some control commands
47、 to the lead-agents in level 3.3.2General characteristicsCompared with the conventional NCS, the DBNCS has several characteristics as follows.(1) Entire harmony. When control disturbance appearances, the field-agents in level 1 first try to eliminate the disturbance. At same time, the information is also sent or fed back to level 2 and 3. Under the regulation of group-agents and lead-agents, the f