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Quantities of data in the DMS (Distribution management system) or SCADA (Supervisory control and data acquisition) system is enormously large as illustrated by the usage of term flooding of data. This enormous quantity of data is transmitted to the status data or event data of the on-site apparatus in real-time. In addition, if GIS (Geographic information system) and AMR (Automatic meter reading), etc are integrated, the quantity of data to be processed in real-time increases unimaginably. Increase in the quantity of data due to addition of system or increase in the on-site facilities cannot be handled through the currently used Single Thread format of data processing technology. However, if Multi Thread technology that utilizes LF-POOL (Leader Follower -POOL) is applied in processing large quantity of data, large quantity of data can be processed in short period of time and the load on the server can be minimized. In this Study, the actual materialization and functions of LF POOL technology are examined.

This paper focuses on performance evaluation of wireless networked control system (NCS) via IEEE 802.15.4 with time-triggered contention-based carrier sensing multiple access with collision (CSMA/CA) algorithm to satisfy the industrial quality-of-service (QoS). Although the IEEE 802.15.4 is considered to a promising protocol for wireless NCS, its performance is not stable and its delay is not bounded under heavy traffic because its medium access control (MAC) is based on the contention-based CSMA/CA scheme. As an alternative approach to avoid these limitations, this paper presents a time-triggered CSMA/CA algorithm for IEEE 802.15.4 non-beacon mode that relies on a time division multiplexing access (TDMA) method. The time-triggered CSMA/CA algorithm for IEEE 802.15.4 non-beacon mode was implemented an experimental wireless NCS, and its control performance was compared with conventional CSMA/CA algorithm. Based on the experimental results, the time-triggered CSMA/CA algorithm is a feasible alternative for wireless NCS.

Recently more and more construction projects have become high-rise, complex and intelligent. Accordingly, such projects require an integrated management system for tasks, with a lean approach to construction with work processes for management and productivity. In particular, Construction Information Technology (CIT) fields are concerned with Building Information Modeling (BIM), which represents the process of generating and managing building data during its life cycle. Constructability research has progressed for the project goal which is a cost-time-quality of optimization by integrated construction knowledge and experience. However, the current constructability process has not been performed efficiently, as the existing 2D drawings and papers lack consistent and accurate information, it is difficult to share the contents of work, and the use of information is inefficient. This study proposes that the reformation and enhancement of BIM-based constructability work process can lead to brilliant performance in the framework of the construction phase through achieving collaboration between the design team and the workers at the site.

The superconductor-triggered type fault current limiter (STFCL), which was developed by Korea Electric Power Corporation (KEPCO) and LS Industrial Systems (LSIS), is under operation for the verification test at KEPCO's power testing center. The STFCL is composed of superconductor, fast switch and current limiting resistor. The fault current is suppressed after a half cycle by the method of a line commutation. In this paper, we investigated the empirical modeling of STFCL using principal components and auto-associative support vector regression (PCSVR) for the prediction and fault detection of the STFCL. Signals for the model are currents and voltages acquired from high-temperature superconductor (HTS), driving coil (DC) and current limiting resistor (CLR). After developing the empirical model we analyse the accuracy of the model. The results were compared with that of auto-associative neural networks (AANN). PCSVR showed much better performance in accuracy aspect. Moreover, this model can be used for the prognosis of STFCL system.

In nuclear power plants (NPPs), periodic sensor calibrations are required to assure that sensors are operating correctly. By checking the sensor’s operating status at every fuel outage, faulty sensors may remain undetected for periods of up to 24 months. Moreover, typically, only a few faulty sensors are found to be calibrated. For the safe operation of NPP and the reduction of unnecessary calibration, on-line instrument calibration monitoring is needed. In this study, principal componentbased auto-associative support vector regression (PCSVR) using response surface methodology (RSM) is proposed for the sensor signal validation of NPPs. This paper describes the design of a PCSVR-based sensor validation system for a power generation system. RSM is employed to determine the optimal values of SVR hyperparameters and is compared to the genetic algorithm (GA). The proposed PCSVR model is confirmed with the actual plant data of Kori Nuclear Power Plant Unit 3 and is compared with the Auto-Associative support vector regression (AASVR) and the auto-associative neural network (AANN) model. The auto-sensitivity of AASVR is improved by around six times by using a PCA, resulting in good detection of sensor drift. Compared to AANN, accuracy and cross-sensitivity are better while the auto-sensitivity is almost the same. Meanwhile, the proposed RSM for the optimization of the PCSVR algorithm performs even better in terms of accuracy, auto-sensitivity, and averaged maximum error, except in averaged RMS error, and this method is much more time efficient compared to the conventional GA method.

Summary The declarative design of graphics lies at the core of the Smart Graphics research agenda. For 3D graphics the number of lights included, and the properties of these lights, has an enormous impact on what a viewer can judge about the content (the objects), properties (the geometric characteristics and spatial relations of the objects) and other aesthetic qualities of a scene. The traditional approach to lighting design for image synthesis is based on manual design methods, whereby users interactively specify values of lighting parameters, render the scene, and modify the lighting parameters until the desired visual properties of the scene are achieved. Non-expert users encounter a number of difficulties in selecting the appropriate lighting parameters, as the process requires both a subtle technical and aesthetic understanding of lighting in computer graphics. We review range of “smart” lighting design and steady slow convergence on ideal lighting approaches which optimise the lighting configuration for a scene with respect to a set of absolute perceptual metrics. More recently perceptual approaches have been combined with aspects of exemplar driven approaches to yield “lighting-by-example” techniques that can replicate the lighting of existing static 2D images and 3D scenes. Zusammenfassung Die Entwicklung deklarativer Methoden zur Generierung von Graphiken ist eines der Hauptanliegen von Smart Graphics. Die Anzahl und Eigenschaften der Lichtquellen haben einen enormen Einfluss auf die Bildwahrnehmung, insbesondere auf den Bildinhalt (Art der Objekte), und die Bildeigenschaften (die geometrischen und raumlichen Beziehung von Objekten), und bestimmen, welchen asthetischen Gesamteindruck ein Bild beim Betrachter hinterlasst. Der klassische Ansatz, Lichtquellen richtig auszuwahlen und zu platzieren, ist traditionell von einer starken interaktiven, manuellen Vorgehensweise gepragt. Der Benutzer spezifiziert alle wichtigen Parameter, bis der gewunschte Lichteffekt eintritt. Insbesondere Laien haben grose Probleme, mit Hilfe dieser Verfahrensweise akzeptable Resultate zu erzielen, da der Vorgang sowohl ein technisches als auch ein asthetisches Verstandnis einfordert. In diesem Artikel untersuchen wir verschiedene Ansatze, dieses Problem zu automatisieren, indem die Anordnung und Parametrisierung der Lichtquellen auf ein bestimmtes absolutes perzeptuelles Zielbild hin optimiert wird. Neuere Ansatze werden prasentiert, die beispielorientiert arbeiten und es Benutzern so ermoglichen, Lichtquellenarrangements zu finden, die klassischen 2D- und 3D-Anordnungen sehr ahnlich sind.

The neutral current is made of both the load unbalanced current and the 3rd harmonic. The 3rd harmonic which is the source of the main neutral current is generated from the loads using bridge rectifier circuits on their input produce currents. TV, computer and monitor which are belong to IEC 61000-3-2 Class D are the main 3rd harmonic current sources. In order to show the affect of the distribution system by these disturbances, this paper has studied the current standards of the Korea Electric and considers the problem of the neutral common.

As the penetration of distributed generation systems is recently high, there have been metering errors, trips of protective devices in KEPCO distribution systems including an occurrence of false fault-indicator in distribution automation system. The cause of malfunctions was the reverse-power-flow phenomenon due to transformer wiring types. By the effect of the reverse-power-flow, each of phase`s fundamental currents was added by about 3 times on the neutral line. A new method based on the analysis of the reverse-power-flow is proposed in this paper. Fault currents on each section were analyzed by the proposed method, and the effect of types of transformer wiring was examined experimentally. In order to reduce the malfunctions due to the reverse-power-flow, controlling the zero-sequence impedance of transformer was designed and verified by using PSCAD/EMTDC software.

Capacitor switching is essential for the economic operation and proper voltage control of KOREA electric utility distribution system. Voltage transients produced by capacitor switching (around 2.0 per unit at substation and 2.5 or less per unit at customer site, and lasting less then 1[ms]) do not have the magnitude or duration to interfere with the operation of computers, but they do disrupt the operation of adjustable speed drivers. The result of our research, ASD manufacturers should learn from the computer industry and design products that will operate satisfactory In the electrical envelopment in which they will be placed. In this case history, the inductors on the input to ADSs in order to prevent nuisance tripping from capacitor switching(and other causes within the apartment) proved to be an effective, low-cost solution.

Electric load components have different characteristics according to the variation of voltage and frequency. This paper presents the load modeling of an electric locomotive by the parameter identification method. The proposed method for load modeling is very simple and easy for application. The proposed load model of the electric locomotive is represented by the combination of the loads that have static and dynamic characteristics. This load modeling is applied to the KTX in Korea to verify the effectiveness of the proposed method. The results of proposed load modeling by the parameter identification follow the field measurements very exactly.

Safety critical systems such as x-by-wire systems require in-vehicle network systems that can interconnect various sensors, actuators, and controllers. These networks need to have high data rate, deterministic operation, and fault tolerance. Recently, FlexRay protocol that is a time-triggered protocol has been introduced, and many automotive companies have been focusing on this protocol. This paper presents a design method of FlexRay network system and implementation of FlexRay-based motor control system.

A yeast transcriptional activator, Gcn4p, induces the expression of genes that are involved in amino acid and purine biosynthetic pathways under amino acid starvation. Gcn4p has an acidic activation domain in the central region and a bZIP domain in the C-terminus that is divided into the DNA-binding motif and dimerization leucine zipper motif. In order to identify amino acids in the DNA-binding motif of Gcn4p which are involved in transcriptional activation, we constructed mutant libraries in the DNA-binding motif through an innovative application of random mutagenesis. Mutant library made by oligonucleotides which were mutated randomly using the Poisson distribution showed that the actual mutation frequency was in good agreement with expected values. This method could save the time and effort to create a mutant library with a predictable mutation frequency. Based on the studies using the mutant libraries constructed by the new method, the specific residues of the DNA-binding domain in Gcn4p appear to be involved in the transcriptional activities on a conserved binding site.

This paper focuses on the feasibility of IEEE 802.11b wireless LAN for real-time wireless industrial network. In general, it has been known that IEEE 802.11b is not suitable for industrial networking because its medium access control method is the contention-based CSMA/CA (Carrier Sensing Multiple Access with Collision Avoidance) that exhibits unstable performance under heavy traffic and unbounded delay distribution. As an attempt to circumvent the probabilistic nature of IEEE 802.11b, this paper presents an enhanced four-layer architecture using the Network Driver Interface Specification (NDIS) and a virtual polling algorithm. Also, the enhanced four-layer architecture's performance is compared with that of conventional IEEE 802.11b. Based on the experimental results, it is found that the enhanced four-layer architecture for IEEE 802.11b is a very promising alternative for wireless industrial networking.

Current KEPCO's distribution automation system (DAS) provides a very effective restoration solution for the single fault case but cannot handle multiple faults. This paper proposes a two-step restoration scheme-sequential and simultaneous restoration-for multiple fault cases. Efficiency has been achieved by introduction of restoration performance index (RPI) and load-balancing algorithm. Test results to show effectiveness of the proposed scheme are presented, and field experience of DAS in Korea is described as well

This paper focuses on routing algorithm with two quality of service constraints: bandwidth and delay. The former is a concave constraint while the later is additive. The goal of algorithm is to accept as many routing requests as possible. Therefore, the proposed algorithm reactively calculates link weights based on link bandwidths. Then, a heuristic idea is applied to Dijkstra in order to find a path satisfying delay constraint and having as little weight as possible. Simulated experiments demonstrate that our proposal have better performance than existing solutions in term of both acceptance ratio and computing time.

In this paper, we present a collocation method based on biquintic splines for a fourth order elliptic problems. To have a better accuracy, we formulate the standard collocation method by an appropriate perturbation on the original differential equations that leads to an optimal approximating scheme. As a result, computational results confirm that this method is optimal.

A full multigrid scheme was used in computing some eigenvalues of the Laplace eigenvalue problem with the Dirichlet boundary condition. We get a system of algebraic equations with an aid of finite difference method and apply subspace iteration method to the system to compute first some eigenvalues. The result shows that this is very effective in calculating some eigenvalues of this problem.

The present study validates and evaluates the sensitivity and specificity of four internationally popular questionnaires, translated into Chinese, for assessing suspected obstructive sleep apnea (OSA) patients, namely, the Berlin questionnaire, the ASA checklist, the STOP questionnaire and the STOP–BANG questionnaire. Their predictive values in OSA risks in patients presenting with OSA symptoms are examined. Questionnaires may be helpful in prioritizing polysomnography (PSG) and in treatment for the more severe cases. All patients attending our sleep laboratory for overnight PSG were recruited. They were asked to complete three questionnaires (Berlin, ASA checklist and STOP) 2 weeks before and on the same night as the PSG. STOP–BANG questionnaire, an extended STOP with demographic data, ‘B’-body mass index (BMI), ‘A’-age, ‘N’-neck circumference and ‘G’-gender was completed by our technologists using the patient’s completed STOP. A number of 141 patients were recruited. The sensitivities and specificities for STOP–BANG with cutoffs at PSG’s RDI = 5, RDI = 15 and RDI = 30 were 81 % to 86 % and 34 % to 57 %, respectively. The high-risk group patients identified by STOP–BANG had significantly higher respiratory disturbance index and lower minimum oxygen saturation than the low-risk group patients. Among the four questionnaires studied, STOP–BANG, with only eight questions and the highest sensitivity, is the best questionnaire of the four for OSA screening. This can potentially assist in prioritizing PSG and can be helpful in clinical or self-evaluation by the general public.

Intelligent distribution automation system(IDAS) was designed to control and monitor the facilities from substation to customer and distributed resources. These facilities have the sensors inside main switchgear equipment that contains ECT, EVT, partial discharge sensor, temperature sensor, water detection sensor, displacement sensor, gas density sensor and so on. It been developed and installed in the testing center of Korea Electric Power Corporation. This paper describes the draft of Power IT project of Korea that have been researching as the first step of Smart-Grid project.

The increasing number of electronic control units, sensors, and actuators in intelligent vehicles, and the increasing need for more intelligent functions require a network with increased capacity and real-time capability. As an example of enhancing the capacity of a controller area network (CAN) system, this paper presents a CAN system with dual communication channels as well as a traffic prediction method that predicts the traffic of each channel to allocates frames to the more appropriate channel. An experimental testbed using off-the-shelf microcontrollers with two CAN controllers was used to prove the feasibility of the traffic prediction method.

In this paper, as make up for the weak points of the centralized restoration in DAS, distributed restoration method applying multi-agent is proposed for increasing the efficiency and saving time of the restoration time of blackouts. Distribution restoration method is difficult to deal with a fault quickly because DAS manage, judge and order the states of distribution network after gathering all information from FRTUs when the fault occurs. If Feeder Remote Terminal Unit (FRTU) in distribution network performs restoration and separates minimized fault section itself by exchanging information using communication to each other, the efficiency and time of the restoration can be enhanced by much. In the case studies, this paper is proposed a distributed restoration method which can make up the weak points of the centralized restoration in DAS by converting FRTUs into multi-agents. The proposed method has been testified in Gochang power test field in Korea and the result in the restoration shows its performance.

This paper presents the feasibility of using the IEEE 802.11b protocol for wireless networked control systems (NCSs). The IEEE 802.11b protocol is considered to be not suitable for industrial networking because the medium access control method is contention-based CSMA/CA, which exhibits unstable performance with an unbounded delay distribution under heavy traffic. To avoid these limitations, we present a four-layer architecture for IEEE 802.11b based on the network driver interface specification (NDIS) combined with a virtual scheduling algorithm. We compare the performance of NDIS-based wireless NCS to that of a conventional wireless NCS. Experimental results show that the NDIS-based four-layer architecture for IEEE 802.11b is a very promising alternative for wireless industrial networking.

This paper presents a fault detection and service restoration method for distribution automation system(DAS) in ungrounded distribution system. Fault detection and service restoration is principal function to supply high reliability power continuously in distribution system. The proposed method utilizes the turning point of fault information between connected feeders in the process of shifting the feeder tie switch. It can provide communication-based fault handling process without power supply interruption for ungrounded distribution system. This method is being studied to be implemented in DAS for field test to validate the method.

Multiple faults which takes a long time to looks for a restoration plan scheme. The first sequential the second simultaneous step performance index and algorithm have been adopted often lead to a large area outage be restored. The proposed method that applies a two-step restoration step treats outages one by one and treats a whole system. A restoration feeder-pair based load-balancing to achieve high efficiency.

As many systems depend on electronics, concern for fault tolerance is growing rapidly. For example, a car with its steering controlled by electronics and no mechanical linkage from steering wheel to front tires (steer-by-wire) should be fault tolerant because a failure can come without any warning and its effect is devastating. In order to make system fault tolerant, there has been a body of research mainly from aerospace field. This paper presents the structure of predictive hybrid redundancy that can filter out most erroneous values. In addition, several numerical simulation results are given where the predictive hybrid redundancy outperforms well-known average and median voters.

This paper presents the feasibility of IEEE 802.11b protocol for real-time wireless industrial network. Generally, because the medium access control method of IEEE 802.11b is the contention-based CSMA/CA that exhibits unstable performance with an unbounded delay distribution under heavy traffic, it has been known that it is not suitable for industrial networking. As an effort for avoiding the uncertainty of IEEE 802.11b, this paper presents a NDIS-based four-layer architecture of IEEE 802.11b with a virtual scheduling method using the network driver interface specification (NDIS). Also, the performance of NDIS-based four-layer architecture is compared with that of conventional architecture of IEEE 802.11b. Based on the experimental results, it is found that the NDIS-based four-layer architecture of IEEE 802.11b is a very promising alternative for wireless industrial networking.

This paper describes a remote monitoring system under developing to assess the health status and/or daily activities of elders who live alone. The developed system is composed of an in-house sensing system and a server system. The in-house sensing system uses a PC and a set of wireless sensor nodes based on the Tiny OS. By using a pyroelectric infrared sensor, the node detects a motion of elder and sends it to a database. The server system has a database server and a Web server, which provides useful information to caregivers for more cost effective intelligent care service. We have evaluated the monitoring system through 3 months continuous operation with installation of 9 elders' house. The experimental results show the promising possibilities to estimate the behavioral patterns and the current status of elder even though the simplicity of sensing capability.

A key issue in mobile and ambient computing is the effort required to rapidly prototype and evaluate user interfaces and applications. Existing technologies for these tasks suffer either from low fidelity (e.g. paper prototypes, mental walkthroughs) or effectively require a near full-scale deployment. We propose an approach using immersive video with surround sound and a simulated infrastructure to create a very realistic environment in the office or the lab. It provides a low-cost and rapid means to prototype user interfaces and applications, and to evaluate them in a realistic simulation of the context, in which they are intended to be used.

Recently, various home network systems, such as LonWorks, Echonet, and LnCP, etc., are developed to enhance customer's comfort and convenience. However, it is not known that performance of any protocol is superior. Hence, this paper evaluates performance of LnCP (Living network Control Protocol) by LG Electronics and LonWorks by Echelon. For this purpose, we have developed simulation model using state diagram of LonWorks and LnCP, and simulation conditions through analysis of message to be generated in the smart home. Also, we evaluate performance, such as maximum transmission delay and mean transmission delay, of both protocols.

The distribution automation system (DAS) will provide supervision and remote control of switches and reclosers such as pole mounted switches and pad mounted switchgears on high voltage distribution line. This can be controlled remotely either automatically or manually, so that it can provide automatic isolation of faulty line sections, which enables quick and accurate recovery of a stable power supply, and also minimizes the out-of-service areas to units of distribution sections. (7 pages)

Smart home is expected to offer various intelligent services by recognizing residents along with their life style and feelings. One of the key issues for realizing the smart home is how to detect the locations of residents. Currently, the research effort is focused on two approaches: terminal-based and non-terminal-based method. The terminal-based method employs a type of device that should be carried by the resident while the non-terminal-based method requires no such device. This paper presents a novel non-terminal-based approach using an array of pyroelectric infrared sensors (PIR sensors) that can detect residents. The feasibility of the system is evaluated experimentally on a test bed

This paper focuses on the feasibility of IEEE 802.11b wireless LAN for real-time wireless industrial network. In general, it has been known that IEEE 802.11b is not suitable for industrial networking because its medium access control method is the contention-based CSMA/CA (carrier sensing multiple access with collision avoidance) that exhibits unstable performance under heavy traffic and unbounded delay distribution. As an attempt to circumvent the probabilistic nature, this paper presents an enhanced four-layer architecture using the network driver interface specification (NDIS) and a virtual polling algorithm. Also, the enhanced four-layer architecture's performance is compared with that of conventional IEEE 802.11b. Based on the experimental results, it is found that the enhanced four-layer architecture for IEEE 802.11b is a very promising alternative for wireless industrial networking.