Terminal Connections Research Articles

Power Distribution Automation System in Green Power Engineering

Not only distribution automation system but the principle of the existing means of communication are studied systematically and distribution automation communication system model based on IP network is provided. Backbone network is set between master station in the control center and substation sub-station. Communication between electronic station and terminal connections rely on the branch network. Simulation experiment shows the test of data traffic and network delay of IP communications network. In the actual network environment the data refresh meet the application requirements. So the program on the improvement of distribution automation communication in this article is feasible.

Wireless Communication in Vehicle Intelligent Network System

Modern cars are integrated with more and more electronic devices, controllers, sensors, actuators, bring more convenience, comfort and safety to the driver. Therefore, complex functions have much higher requirement on communication network, with higher speed, so accelerate new type of vehicle network application, such as FlexRay, Ethernet, and etc. Wireless connection could provide a convenient and flexible topology, transport protocol solution, also could resolve vehicle electronic limit. This paper proposes vehicle network system architecture based on communication, including three types of wireless application on the network, covering three major direction, intelligent terminal connection, wireless diagnostic, telematics and some solutions on the key points specific. Description in the paper is already built to specification, and integrated in the test samples of the related electric control system on the demo car.

Satb1 Is an Activity-Modulated Transcription Factor Required for the Terminal Differentiation and Connectivity of Medial Ganglionic Eminence-Derived Cortical Interneurons

Although previous work identified transcription factors crucial for the specification and migration of parvalbumin (PV)-expressing and somatostatin (SST)-expressing interneurons, the intrinsic factors required for the terminal differentiation, connectivity, and survival of these cell types remain uncharacterized. Here we demonstrate that, within subpopulations of cortical interneurons, Satb1 (special AT-rich binding protein) promotes terminal differentiation, connectivity, and survival in interneurons that express PV and SST. We find that conditional removal of Satb1 in mouse interneurons results in the loss of a majority of SST-expressing cells across all cortical layers, as well as some PV-expressing cells in layers IV and VI, by postnatal day 21. SST-expressing cells initially migrate to the cortex in Satb1 mutant mice, but receive reduced levels of afferent input and begin to die during the first postnatal week. Electrophysiological characterization indicates that loss of Satb1 function in interneurons results in a loss of functional inhibition of excitatory principal cells. These data suggest that Satb1 is required for medial ganglionic eminence-derived interneuron differentiation, connectivity, and survival.

Failure Development in a System of Two Connected Networks

We consider a pair of networks A and B which are subject to failures of their components. In A, edges are subject to failure, and A fails when it disintegrates into several isolated clusters each containing a single terminal. Edges of A fail in random order and their failure moments follow Poisson process. After A has failed, terminal α of A causes a failure (”attacks”) on Rα randomly chosen non terminal nodes of network B. All edges incident to an attacked node are erased. The ”attacks” take negligible time. Network B failure takes place if it loses its terminal connectivity. We study the probability that B will be in failure state at moment t as a function of t and R = ∑ Rα The main formal tools which we use are the D-spectra (signatures) of networks A and B and de Moivre’s combinatorial formula.

A vertex cut algorithm for model order reduction of parasitic resistive networks

PurposeTo simulate large parasitic resistive networks, one must reduce the size of the circuit models through methods that are accurate and preserve terminal connectivity and network sparsity. The purpose here is to present such a method, which exploits concepts from graph theory in a systematic fashion.Design/methodology/approachThe model order reduction problem is formulated for parasitic resistive networks through graph theory concepts and algorithms are presented based on the notion of vertex cut in order to reduce the size of electronic circuit models. Four variants of the basic method are proposed and their respective merits discussed.FindingsThe algorithms proposed enable the production of networks that are significantly smaller than those produced by earlier methods, in particular the method described in the report by Lenaers entitled “Model order reduction for large resistive networks”. The reduction in the number of resistors achieved through the algorithms is even more pronounced in the case of large networks.Originality/valueThe paper seems to be the first to make a systematic use of vertex cuts in order to reduce a parasitic resistive network.

Optimized Modeling of Transformer in Transient State with Genetic Algorithm

In this paper a straightforward model is proposed for transient analysis of transformers. The model is capable of representing the impedance or admittance characteristics of the transformer measured from the terminals under different terminal connections up to approximately 200 kHz. The model is simple, so that the simulation with this model is easy and fast. It is feasible to use the model as a two port element by network analysing. To estimation of model parameters genetic algorithm is used. Outset of all, the required measurements are carried out on the 2500 KVA, 6300/420 V transformer. Thereafter, the model parameters are estimated using genetic algorithm toolbox in MATLAB. The comparison between calculated and measured quantities confirms that the accuracy of the proposed method in the middle transient frequency domain is satisfactory. Finally, one of important application of proposed model in transformers fault detection is discussed.

Effects of terminal connections on sweep frequency response analysis of transformers

Many problems can arise in power transformers, beginning from the moment they arrive at the sites where they are to be installed [1], [2]. Sweep frequency response analysis (SFRA) is used by many industries and manufacturers to assess the mechanical integrity of the core, winding, and clamping structure of power transformers. It usually involves the application of low-voltage (LV) signal (2 to 15 V) at one terminal of the transformer, over the frequency range 20 Hz to 2 MHz, and measurement of the response at another terminal, as shown in Figure 1 [1]. The amplitude and phase transfer function are then determined.

두 개의 Quasi Z-소스 AC-AC 컨버터에 의한 6.6[kV]/60[Hz] 배전계통의 동적 전압 보상기(DVR)

This paper proposes a quasi Z-source DVR(Dynamic Voltage Restorer) system with a series connection of the output terminals, to compensate the voltage variations in the 6.6[kV]/60[Hz] power distribution system. The conventional DVR using one quasi Z-source AC-AC converter has the advantage which it can compensate the voltage variations without the need for the additional energy storage device such as a battery, but it is impossible to compensate for the 50[%] under voltage sags. To solve this problem, a DVR system using two quasi Z-source AC-AC converters with the series connection of the output terminals is proposed. By controlling the duty ratio D in the buck-boost mode, the proposed system can control the compensation voltage. For case verification of the proposed system, PSIM simulation is achieved. As a result, in case that the voltage sags-swells occur 10[%], 20[%], 60[%] in power distribution system, and, in case that the 50[%] under voltage sags-swells continuously occur, all case could compensate by the proposed system. Especially, the compensated voltage THD was examined under the condition of the 10[%]∼50[%] voltage sags and the 20[Ω]∼100[Ω] load changes. The compensated voltage THD was worse for the higher load resistances and more severe voltage sags. Finally, In case of the voltage swells compensation, the compensation factor has approached nearly 1 regardless of the load resistance changes, while the compensation factor of voltage sags was related to the load variations.

COMBINATORIAL APPROACH TO COMPUTING COMPONENT IMPORTANCE INDEXES IN COHERENT SYSTEMS

We consider binary coherent systems with independent binary components having equal failure probability q. The system DOWN probability is expressed via its signature's combinatorial analogue, the so-called D-spectrum. Using the definition of the Birnbaum importance measure (BIM), we introduce for each component a new combinatorial parameter, so-called BIM-spectrum, and develop a simple formula expressing component BIM via the component BIM-spectrum. Further extension of this approach allows obtaining a combinatorial representation for the joint reliability importance (JRI) of two components. To estimate component BIMs and JRIs, there is no need to know the analytic formula for system reliability. We demonstrate how our method works using the Monte Carlo approach. We present several examples of estimating component importance measures in a network when the DOWN state is defined as the loss of terminal connectivity.

출력이 직렬 결합된 단상 Quasi Z-소스 AC-AC 컨버터

본 연구에서는 출력이 직렬 연결된 단상 quasi Z-소스 AC-AC 컨버터를 제안하였다. 제안된 시스템은 단상quasi Z-소스 AC-AC 컨버터 2대의 입력 단을 병렬로 연결하고 출력 단을 직렬로 연결한 구조로 되어 있으며, 역상 모드와 동상 모드 별 전류 흐름과 출력전압의 형성 과정을 나타내었다. DSP로 제어되는 실험 시스템을 제작하여 PSIM시뮬레이션 결과와 비교 분석하였다. 그 결과 각 모드별로 듀티 비를 제어하여 원하는 출력 전압을 벅-부스트 할 수 있었다. 컨버터 1대가 단독으로 운전한 경우에 비하여, 각각의 모드에 대하여 부하 저항의 증가에 따른컨버터 효율과 입력 역률을 제안된 방법에 의하여 개선할 수 있었다. 또한 역상 모드의 경우, 일정 부하에서 컨버터의 효율과 입력 역률을 각각 10[%]와 35[%]정도 개선하였으며, 특히 부하 저항이 변동하는 과도상태에서도 일정한 출력 전압을 유지할 수 있었다. In this study, a single-phase quasi Z-source AC-AC converters with a series connection of the output terminals is proposed. The proposed system has configuration that the input terminals of two quasi Z-source AC-AC converters are connected in parallel and its output terminals are connected in series. The out of phase mode and in phase mode of the proposed system are presented. To verify the validity of the proposed converter, a DSP controlled hardware was made and PSIM simulation was executed. As a result, controlling the duty ratio of the converter, the desired buck-boost output voltages could be generated. For each modes, as compared with the single converter operation, the proposed converter could enhance the efficiency and input power factor according to different loads. Also, in case of the out of phase mode under the constant load, the efficiency and input power factor of the proposed system are increased 10[%], 35[%] respectively in compared with the single converter. And, the output voltage is constantly controlled in dynamic state in case while the load is suddenly changed.

Urocortin‐expressing olivocochlear neurons exhibit tonotopic and developmental changes in the auditory brainstem and in the innervation of the cochlea

The mammalian cochlea is under direct control of two groups of cholinergic auditory brainstem neurons, the medial and the lateral olivocochlear neurons. The former modulate the electromechanical amplification in outer hair cells and the latter the transduction of inner hair cells to auditory nerve fibers. The lateral olivocochlear neurons express not only acetylcholine but a variety of co-transmitters including urocortin, which is known to regulate homeostatic responses related to stress; it may also be related to the ontogeny of hearing as well as the generation of hearing disorders. In the present study, we investigated the distribution of urocortin-expressing lateral olivocochlear neurons and their connectivity and distribution of synaptic terminals in the cochlea of juvenile and adult gerbils. In contrast to most other rodents, the gerbil's audiogram covers low frequencies similar to humans, although their communication calls are exclusively in the high-frequency domain. We confirm that in the auditory brainstem urocortin is expressed exclusively in neurons within the lateral superior olive and their synaptic terminals in the cochlea. Moreover, we show that in adult gerbils urocortin expression is restricted to the medial, high-frequency processing, limb of the lateral superior olive and to the mid and basal parts of the cochlea. The same pattern is present in juvenile gerbils shortly before hearing onset (P 9) but transiently disappears after hearing onset, when urocortin is also expressed in low-frequency processing regions. These results suggest a possible role of urocortin in late cochlear development and in the processing of social calls in adult animals.

Design and Performance of Novel Optical Fiber Distribution and Management System With Testing Functions in Central Office

This paper describes the design and performance of a novel central office optical fiber distribution and management system for optical access networks. We clarify the requirements for an optical fiber distribution and management system with a testing function. We propose integrated distribution modules (IDMs) and high-count indoor cables for high-capacity cable termination and cross connection, a management system using identification tags for easy administration and reference with respect to the distribution facilities, and a new optical fiber line testing system using an optical testing module with a 1650 nm optical time-domain reflectometer for in-service testing. We evaluated the prototype system. The prototype IDM could accommodate 4000 fibers and the insertion loss of the communication lines and the system dynamic range of testing system met our requirements for use in an optical access network including a 7 km outside cable and an eight-branch optical splitter. We compared the cost and testing time required for the conventional and proposed systems. We found that the proposed distribution system can reduce the distribution cost by 40% and connection work time by 12% compared with the conventional system. We also found that the testing system can reduce the system cost by 63% compared with the conventional testing system and required testing time is 73% less than testing time by hand, thus reducing the operations, administration, and maintenance costs.

Reducing Common-Mode Noise in Two-Switch Forward Converter

This paper addresses the common-mode (CM) electromagnetic interference noise issues in the two-switch forward converter. The two-switch forward converter has low CM noise compared to other topologies because its symmetric primary-side circuit has two out-of-phase dv/dts that cancel each other. However, parasitic capacitances of the circuit significantly affect the symmetry and degrade the noise reduction. Moreover, the secondary-side circuit of the converter is not symmetric and still contributes to the CM noise. In this paper, the parasitic capacitances of the converter are first modeled. Different transformer structures and their parasitic capacitances are characterized. A general balance technique is introduced to further reduce the CM noise of the converter. For each transformer structure, balance can be achieved with proper connection of the windings terminals and control of the parasitic capacitances to minimize the CM noise of the converter. Experimental results validated the proposed techniques.

Stator‐core structure and winding technology for EPS motors

AbstractElectric power steering (EPS) motors must have the performance characteristics of precision machines. They should be compact and produce high power. Moreover, the loss torque and the change of loss torque should be as low as possible. In this study, dividing the stator core into small blocks and winding the coils densely on the blocks are shown to be effective techniques for achieving compact high‐power motors. We examined whether I‐shaped divided cores or T‐shaped divided cores were more suitable for EPS motors in terms of motor performance and production cost. We built two experimental motors, one with I‐shaped divided cores and the other with T‐shaped divided cores, and measured three important characteristics of EPS motors: output torque, loss torque, and loss torque change. The T‐type motor proved to have better performance for all three characteristics. Moreover, the productivity of the T‐type motor was shown to be higher than that of the I‐type motor, indicating that overall, T‐shaped divided cores are advantageous for the stators of EPS motors. Next, we considered a new winding method for the continuous winding of two T‐shaped cores in order to achieve a compact terminal connection board. The extending lines made by the new winding method do not extend beyond the coil end. Therefore, this method will contribute to reduction of the axial dimension of EPS motors. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(1): 35–42, 2011; Published online in Wiley Online Library (wileyonlinelibrary.com). DOI 10.1002/eej.21085

Glowing Connection Experiments With Alternating Currents Below 1${\rm A}_{\rm rms}$

It was experimentally shown that a glowing connection can develop in an electrical switch at a terminal connection comprised of a connector that utilizes a spring action against a conductor to provide electrical contact in household electrical appliances where vibration exists, and when the connection is loose. This can happen at a current flow such as 0.6 A <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">rms</sub> at 120-V. Further, the glow can provide sufficient heat to degrade plastic in contact with the terminal components. Violent arcing involving intense gasification can then develop on nearby plastic areas, sometimes accompanied by intensely glowing areas inside the plastic. Sometimes the intense glowing areas inside plastic develop without the violent arcing. The intense arcing or the glow inside plastic often develops into flaming, which can be of sufficient intensity and duration to ignite combustible materials near the connection.

이종망에서 이동 단말기의 QoS를 향상시키는 정책기반 자원관리 프레임워크

본 논문에서는 이종 접속망에서 이동 단말기 및 접속망 상태 등에 따라 가변적으로 변하는 자원관리 기능을 이동 단말기의 핸드오버 처리에 적용함으로써 최적의 QoS를 보장할 수 있는 정책기반 자원관리 프레임워크를 제안하였다. 본 논문에서 제안한 정책기반 자원관리 프레임워크의 성능을 평가하기 위하여 중첩된 이종 접속망간에서 발생하는 핸드오버시 최적의 셀을 선정하기 위한 가중치 정책을 적용했을 경우, 멀티미디어 서비스 세션의 수가 증가할수록 전송 지연이 현저히 향상된 것으로 분석되었다. 이는 서비스 중인 접속망에서 QoS 저하가 발생할 경우에 최적의 접속망으로 핸드오버가 수행되어 현재 서비스에 가장 적합한 이종 시스템으로의 서비스 절체가 이루어지므로 서비스의 연속성을 최대한 보장할 수 있다. A policy based resource management framework is proposed, that supports the optimal QoS by applying resources management function which is changed according to the status of mobile terminal and heterogeneous connections to hand-over process of mobile terminals based on heterogeneous network. To assess the performance of policy based resource management framework proposed in this thesis, in case of applying weighted policy for selecting optimal cell in hand-over occurring among duplicated heterogeneous connections, the transmission delay was remarkably enhanced as the number of multimedia sessions increased. This means, in case of QoS deterioration of multimedia session occurring in service connection, hand-over was executed with the optimal connection.

Gradient RSSI Filter and Predictor for Wireless Network Algorithms and Protocols

Wireless networks, and in particular Wireless Fidelity ( WiFi ) networks, present important problems of connectivity among wireless terminals. These problems lead to inefficiencies in the Application level. For localization algorithms in wireless networks, efficient handover protocols and multimedia delivery information, these problems must be solved. A figure used to control the connectivity of terminals to other terminals or to an Access Point ( AP ) is the well known Received Signal Strength Indicator ( RSSI ). Managing this figure it is possible to control the availability of a service in the wireless terminal. But the problem with RSSI is the fact that it exhibits high variability in space and time. Thus it is important to filter those values in order to efficiently manage the availability of the service in the mobile terminal. For that reason in this paper we present the experimental validation of a filter and a predictor of availability of a service in the wireless terminal based on the RSSI. We test the performance of the filter and the predictor that improves significantly other filters that are also presented in the paper. The significance of our work is that our filter allows simplifying a lot of network algorithms and protocols. As an example we present a simple protocol of handover in presence of multimedia information using our filter and predictor based on RSSI.

Influence of Rotor Cage on the Performance of a Synchronous Reluctance Generator

The influence of rotor cage on the performance of an autonomous self-excited reluctance generator supplying loads of different power factors is presented. It is seen that for the same excitation capacitance, terminal load connection, and speed, the self-excited reluctance generator with a cage exhibits a better ability to preserve the voltage waveshape following a sudden addition or removal of load than does a cageless self-excited reluctance generator. This is because during the transient disturbance, the rotor cage supports some DC current in the d-axis, making it act as a field winding. The solution of steady-state model equations formulated directly from the dynamic model are solved using the MATLAB® (The MathWorks, Natick, Massachusetts, USA) optimization technique ‘fsolve.’ The cageless self-excited reluctance generator is only capable of yielding less than half the rated power, while the self-excited reluctance generator with a cage is able to produce more than two-thirds of the rated power. This is due to the inability of the cageless machine to excite at capacitance values high enough to circulate the rated current in the machine windings.

Investigation of LOCOS- and Polysilicon-Bound Diodes for Robust Electrostatic Discharge (ESD) Applications

In this paper, the current-carrying and voltage-clamping capabilities of LOCal Oxidation of Silicon (LOCOS)- and polysilicon-bound diodes are first investigated. Comparison of these capabilities leads to the conclusion that the polysilicon-bound diode is more suited for electrostatic discharge (ESD) protection applications. Then, to achieve an optimal diode structure for ESD applications, the effects of the cathode/anode length, cathode/anode width, polysilicon width, finger number, terminal connection, and metal layout on the polysilicon-bound diode's ESD robustness are studied and discussed in detail.

Ultrastructural analysis of the synaptic connectivity of TRPV1-expressing primary afferent terminals in the rat trigeminal caudal nucleus

Trigeminal primary afferents that express the transient receptor potential vanilloid 1 (TRPV1) are important for the transmission of orofacial nociception. However, little is known about how the TRPV1-mediated nociceptive information is processed at the first relay nucleus in the central nervous system (CNS). To address this issue, we studied the synaptic connectivity of TRPV1-positive (+) terminals in the rat trigeminal caudal nucleus (Vc) by using electron microscopic immunohistochemistry and analysis of serial thin sections. Whereas the large majority of TRPV1+ terminals made synaptic contacts of an asymmetric type with one or two postsynaptic dendrites, a considerable fraction also participated in complex glomerular synaptic arrangements. A few TRPV1+ terminals received axoaxonic contacts from synaptic endings that contained pleomorphic synaptic vesicles and were immunolabeled for glutamic acid decarboxylase, the synthesizing enzyme for the inhibitory neurotransmitter γ-aminobutyric acid (GABA). We classified the TRPV1+ terminals into an S-type, containing less than five dense-core vesicles (DCVs), and a DCV-type, containing five or more DCVs. The number of postsynaptic dendrites was similar between the two types of terminals; however, whereas axoaxonic contacts were frequent on the S-type, the DCV-type did not receive axoaxonic contacts. In the sensory root of the trigeminal ganglion, TRPV1+ axons were mostly unmyelinated, and a small fraction was small myelinated. These results suggest that the TRPV1-mediated nociceptive information from the orofacial region is processed in a specific manner by two distinct types of synaptic arrangements in the Vc, and that the central input of a few TRPV1+ afferents is presynaptically modulated via a GABA-mediated mechanism.