DOWNLOAD PDF SOCIAL RESPONSES TO LARGE TECHNICAL SYSTEMS: CONTROL OR ANTICIPATION

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1 Chapter 1 : INFORMATION MANAGEMENT & TECHNOLOGY This volume stems from the efforts of scholars who seek to understand the social dynamics of large technical systems. The purpose is to develop concepts and empirical knowledge concerning the dynamics of such systems, with particular emphasis on the processes ofcontrol and/or management in a. The brain structures that compose the reward system are located primarily within the cortico-basal ganglia-thalamo-cortical loop ; [11] the basal ganglia portion of the loop drives activity within the reward system. The reward system includes the ventral tegmental area, ventral striatum i. These LHb projections are activated both by aversive stimuli and by the absence of an expected reward, and excitation of the LHb can induce aversion. While GABA receptor agonists are capable of eliciting both "liking" and "wanting" reactions in the nucleus accumbens, glutaminergic inputs from the basolateral amygdala, ventral hippocampus, and medial prefrontal cortex can drive incentive salience. Furthermore, while most studies find that NAcc neurons reduce firing in response to reward, a number of studies find the opposite response. This had led to the proposal of the disinhibition or depolarization hypothesis, that proposes that excitation or NAcc neurons, or at least certain subsets, drives reward related behavior. Regions include the lateral hypothalamus and medial forebrain bundles, which are especially effective. Stimulation there activates fibers that form the ascending pathways; the ascending pathways include the mesolimbic dopamine pathway, which projects from the ventral tegmental area to the nucleus accumbens. There are several explanations as to why the mesolimbic dopamine pathway is central to circuits mediating reward. First, there is a marked increase in dopamine release from the mesolimbic pathway when animals engage in intracranial self-stimulation. Pleasure centers [ edit ] Pleasure is a component of reward, but not all rewards are pleasurable e. The posterior ventral pallidum also contains a hedonic hotspot, while the anterior ventral pallidum contains a hedonic coldspot. Microinjections of opioids, endocannabinoids, and orexin are capable of enhancing liking in these hotspots. Furthermore, inhibition of one hotspot results in the blunting of the effects of activating another hotspot. Incentive salience Tuning of appetitive and defensive reactions in the nucleus accumbens shell. Above AMPA blockade requires D1 function in order to produce motivated behaviors, regardless of valence, and D2 function to produce defensive behaviors. GABA agonism, on the other hand, does not requires dopamine receptor function. Below The expansion of the anatomical regions that produce defensive behaviors under stress, and appetitive behaviors in the home environment produced by AMPA antagonism. This flexibility is less evident with GABA agonism. In the NAcc, such a dichotomy is not as clear cut, and activation of both D1 and D2 MSNs is sufficient to enhance motivation, [37] [38] likely via disinhibiting the VTA through inhibiting the ventral pallidum. To explain increasing contact with a certain stimulus such as chocolate, there are two independent factors at work â our desire to have the chocolate wanting and the pleasure effect of the chocolate liking. According to Robinson and Berridge, wanting and liking are two aspects of the same process, so rewards are usually wanted and liked to the same degree. However, wanting and liking also change independently under certain circumstances. For example, rats that do not eat after receiving dopamine experiencing a loss of desire for food act as though they still like food. In another example, activated self-stimulation electrodes in the lateral hypothalamus of rats increase appetite, but also cause more adverse reactions to tastes such as sugar and salt; apparently, the stimulation increases wanting but not liking. Such results demonstrate that our reward system includes independent processes of wanting and liking. The wanting component is thought to be controlled by dopaminergic pathways, whereas the liking component is thought to be controlled by opiate-benzodiazepine systems. The same animals do not work to obtain the opiates if the dopaminergic neurons of the mesolimbic pathway are inactivated. In this perspective, animals, like humans, engage in behaviors that increase dopamine release. Kent Berridge, a researcher in affective neuroscience, found that sweet liked and bitter disliked tastes produced distinct orofacial expressions, and these expressions were similarly displayed by human newborns, orangutans, and rats. This was evidence that pleasure Page 1

2 specifically, liking has objective features and was essentially the same across various animal species. Most neuroscience studies have shown that the more dopamine released by the reward, the more effective the reward is. This is called the hedonic impact, which can be changed by the effort for the reward and the reward itself. Berridge discovered that blocking dopamine systems did not seem to change the positive reaction to something sweet as measured by facial expression. In other words, the hedonic impact did not change based on the amount of sugar. This discounted the conventional assumption that dopamine mediates pleasure. Even with more-intense dopamine alterations, the data seemed to remain constant. It explains the compulsive use of drugs by drug addicts even when the drug no longer produces euphoria, and the cravings experienced even after the individual has finished going through withdrawal. Some addicts respond to certain stimuli involving neural changes caused by drugs. This sensitization in the brain is similar to the effect of dopamine because wanting and liking reactions occur. Human and animal brains and behaviors experience similar changes regarding reward systems because these systems are so prominent. Associative learning Rewarding stimuli can drive learning in both the form of classical conditioning Pavlovian conditioning and operant conditioning instrumental conditioning. In classical conditioning, a reward can act as an unconditioned stimulus that, when associated with the conditioned stimulus, causes the conditioned stimulus to elicit both musculoskeletal in the form of simple approach and avoidance behaviors and vegetative responses. In operant conditioning, a reward may act as a reinforcer in that it increases or supports actions that lead to itself. Model free learning involves the simple caching and updating of values. In contrast, model based learning involves the storage and construction of an internal model of events that allows inference and flexible prediction. Although pavlovian conditioning is generally assumed to be model-free, the incentive salience assigned to a conditioned stimulus is flexible with regard to changes in internal motivational states. Although classical conditioning is not limited to the reward system, the enhancement of instrumental performance by stimuli i. Habitual and goal directed instrumental learning are dependent upon the lateral striatum and the medial striatum, respectively. The intracellular cascade activated by D1 receptors involves the recruitment of protein kinase A, and through resulting phosphorylation of DARPP, the inhibition of phosphatases that deactivate ERK. They discovered that rats would perform behaviors such as pressing a bar, to administer a brief burst of electrical stimulation to specific sites in their brains. This phenomenon is called intracranial self-stimulation or brain stimulation reward. Typically, rats will press a lever hundreds or thousands of times per hour to obtain this brain stimulation, stopping only when they are exhausted. While trying to teach rats how to solve problems and run mazes, stimulation of certain regions of the brain where the stimulation was found seemed to give pleasure to the animals. They tried the same thing with humans and the results were similar. The explanation to why animals engage in a behavior that has no value to the survival of either themselves or their species is that the brain stimulation is activating the system underlying reward. When rats were tested in Skinner boxes where they could stimulate the reward system by pressing a lever, the rats pressed for hours. Pavlov used the reward system by rewarding dogs with food after they had heard a bell or another stimulus. Pavlov was rewarding the dogs so that the dogs associated food, the reward, with the bell, the stimulus. Thorndike used the reward system to study operant conditioning. He began by putting cats in a puzzle box and placing food outside of the box so that the cat wanted to escape. The cats worked to get out of the puzzle box to get to the food. Although the cats ate the food after they escaped the box, Thorndike learned that the cats attempted to escape the box without the reward of food. Thorndike used the rewards of food and freedom to stimulate the reward system of the cats. Thorndike used this to see how the cats learned to escape the box. Page 2

3 Chapter 2 : Reward system - Wikipedia social responses to large technical systems control or anticipation blog.quintoapp.com Free Download social responses to large technical systems control or anticipation. If the Particle Counter is equal to the total Number of Particles in the set of programmable parameters, going to Step 9. If not, going to Step 4; Step 9: Incrementing the Iteration Counter; and Step The system of claim 16 or claim 17 or claim 18 wherein the set of programmable parameters of the load anticipation feature comprise at least one of: The system of claim 13 wherein the computer executable instructions are further structured whereby: Deregulation of electrical utilities has resulted in many customers utilizing their standby diesel gensets to improve power quality or to avoid peak electricity tariffs. Gensets often consists of a diesel engine, a synchronous machine, and two controllers a speed governor and an automatic voltage regulator "AVR". The speed governor seeks to maintain the diesel engine at a constant speed. Unlike the large size generators, many gensets may be expected to change operation from unloaded to full load in a single step load application, which causes large changes in engine speed or may cause the engine to stall. International Standard ISO; provides a means to assess diesel genset performance, which classifies a genset based on a series of key performance indicators. Voltage recovery time must be less than 6 seconds and frequency recovery time be less than 5 seconds. While some diesel genset controllers are able to meet the requirements of ISO;, such controllers are expensive to manufacture. A common way to reduce the engine speed drop is to provide an additional voltage dip during speed drops. Thus, faster engine speed recovery is achieved by reducing the real power load. A load adjustment scheme has been suggested which temporarily reduces the voltage during a transient and therefore aids engine speed recovery. As such, the inventor hereof has identified a need for a system and method that can reduce the engine speed deviation of a genset when the real power load changes. SUMMARY OF THE INVENTION The present invention provides a method, system and computer software for providing a load anticipation feature for a diesel generating set including a diesel engine, a generator, a speed governor, and an automatic voltage regulator including the functions of ascertaining an equivalent linear speed control system, the response of the linear speed control system approximately matching the non-linear speed response of the diesel generating set and ascertaining at least one programmable parameter of a load anticipation feature based on a real power load applied to the diesel generating set and a desired speed response of the linear speed control system. The system and method can also include the functions of measuring a real power load applied to the diesel generating set by a sensor electrically coupled to the diesel generating set, providing the at least one programmable parameter of the load anticipation feature to a computer data processor apparatus having computer memory, the computer memory containing computer executable instructions for implementing the equivalent linear speed control system and the load anticipation feature, the computer executable instructions for implementing the load anticipation feature including instructions to generate a control output based on the measured real power load and the at least one programmable parameter of the load anticipation feature. The system and method can further include providing the control output to the speed governor, the speed governor adjusting the speed of the diesel engine based on the control output. The present system and method are applicable to a diesel genset 10, a block diagram of which is illustrated in Fig. The diesel genset 10 can include a diesel engine 12, a synchronous machine, or generator, 14, an exciter 16, a speed governor 18 and an automatic voltage regulator "AVR" The diesel genset 10 can be connected to a real power load The interaction between voltage control and speed control of the diesel genset 10 is shown in the functional block diagram of Fig 2. Each block in Fig. In the description that follows for Figs. The input to the functional block diagram, Vref 17, is a constant that represents the desired generator voltage. The speed governor 18 can be operatively coupled to a fuel pump The output of the fuel pump 24 block represents the mechanical torque, denoted as Tm. The electrical torque, Te, can be determined based on the generator voltage 15, denoted as Vt and the resistive load, R The friction Page 3

4 torque can be denoted as Tf. The speed governor 18 can include a communications interface for receiving a control output. The speed governor 18 can adjust the speed of the diesel engine 12 based in whole or in part on the received control output. The total moment of inertia 36 can be determined in part based on the construction of the diesel engine 12 and the generator 14, including the rotating parts of each, and is represented as a function of the total engine inertia H The AVR 20 can be operatively coupled to the exciter 16 through a power amplifier The actual desired speed response is represented as co A feedback signal, f co 21, can be generated as a function of Tm, Tf, Te, and H After detecting this deceleration, the speed governor 18 can instruct the fuel pump 24 to increase the fuel supplied to the cylinders of the diesel engine Since real power is proportional to the square of the voltage, a fast acting AVR 20 will significantly impede diesel engine 12 speed recovery by quickly recovering the voltage and therefore placing more load on the diesel engine Thus, a speed governor 18 reaction to a speed change due to real power load 22 application is slower than of the real power change. In a modem AVR, a measurement of the real power load 22 is available. Thus, in order to reduce the speed deviation when a large real power load 22 is applied, a load anticipation feature "LAF", which adds a feed-forward signal proportional to the change in the real power load 22 to the speed governor 18 error summing point during the transient conditions, is more effective than the conventional approaches which change the setpoint of the AVR 20 based on a specific under frequency curve. PSO is an evolutionary computation technique inspired by the social behavior of bird flocking or fish schooling. In PSO, the potential particles solutions fly through the problem space by following the current optimum particles. Each particle keeps track of its coordinates in the problem space and communicates the best solution found to the other particles. This communication between particles allows an intelligent decision at each iteration to find the best possible solution for a given set of programmable parameters. Determination of an Equivalent Linear Speed Control System In order to implement the LAF, programmable parameters of an equivalent linear speed control system must be determined. A functional block diagram of the equivalent linear speed control system 26 is shown in Fig. The equivalent linear speed control system 26 can include quantities representing a governor, actuator 34, engine combustion function, and moment of inertia Engine performance is non-linearly affected by changes in operating speed, real power load and AVR response. Thus, in order to implement desired speed response of the generator speed control system including the LAF, an equivalent linear speed control system can be derived, the response of which approximately matches the nonlinear speed response of the actual diesel genset The equivalent linear speed control system 26 can include a Proportional, Integral, and Derivative PID controller 32 type of a speed governor 18, an actuator 34, a moment of inertia 36, and Speed Droop 38 as illustrated in Fig 3. The PID controller 32 can include one or more programmable parameters. In the exemplary embodiment of Fig. TD 45 represents a derivative time constant which is a design constant for the PID. The term "s" 48 represents the Laplace operator. The actuator 34 can include an actuator time constant TA The mechanical torque Tm 52 can be determined as a function of the output of the actuator 34 and the generator 14 real power output PE The moment of inertia 36 of the diesel engine 12 can be represented as a function of the total engine inertia H The output of the equivalent linear speed control system 26 can be co 56, which represents the desired speed response of the speed of the diesel engine A block diagram of a procedure, according to an exemplary embodiment, that can be used to identify the programmable parameters of the equivalent linear speed control system 26 is illustrated in Fig. As described more fully below, the Adjusted Programmable Parameters 70 can be provided to the equivalent linear speed control system The Programmable Parameter Adjustment Rule by PSO 68 can be initialized with a group of five particles solutions based on the particular configuration i. Each particle can include one or more programmable parameters, which coincide with the programmable parameters of the equivalent linear speed control system 26 model. Chapter 3 : CiNii å ³æ - Social responses to large technical systems : control or anticipation Page 4

5 Proceedings of the NATO Advanced Research Workshop on Social Responses to Large Technical Systems: Regulation, Management, or Anticipation, Berkeley, California, October, Page 5