• Title/Summary/Keyword: Task Interruption

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Optimum Path Planning for Mechanical Manipulators (기계적 로보트팔을 위한 최적 경로 설계)

  • Kim, Tae-San;Bae, Jun-Kyung;Park, Chong-Kug
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.941-944
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    • 1988
  • To assure a successful completion of an assigned task without interruption, the hand of mechnical manipulator often travels along a preplanned path. This paper presents a method of obtaining a time sechdule of velocities and acceleration along the path, under the constraints. Because of the involvement of a linear performance index and a largr number of nonlinear constraints, the "method of approximate programming (AMP)" is applied. To overcome the false solutions AMP is modified. To reduce the computing time, a "direct approximate programming algorithm (DAPA)" is developed.

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Rate Control Scheme for Improving Quality of Experience in the CoAP-based Streaming Environment (CoAP 기반의 스트리밍 환경에서 사용자 체감품질 향상을 위한 전송량 조절 기법)

  • Kang, Hyunsoo;Park, Jiwoo;Chung, Kwangsue
    • Journal of KIISE
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    • v.44 no.12
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    • pp.1296-1306
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    • 2017
  • Recently, as the number of Internet of Things users has increased, IETF (Internet Engineering Task Force) has released the CoAP (Constrained Application Protocol). So Internet of Things have been researched actively. However, existing studies are difficult to adapt to streaming service due to low transmission rate that result from buffer underflow. In other words, one block is transmitted one block to client's one request according to the internet environment of limited resources. The proposed scheme adaptively adjusts the rate of CON(Confirmable) message among all messages for predicting the exact network condition. Based on this, the number of blocks is determined by using buffer occupancy rate and content download rate. Therefore it improves the quality of user experience by mitigating playback interruption. Experimental results show that the proposed scheme solves the buffer underflow problem in Internet of Things streaming environment by controlling transmission rate according to the network condition.

Development of MEMS Accelerometer-based Smart Sensor for Machine Condition Monitoring (MEMS 가속도계 기반의 기계 상태감시용 스마트센서 개발)

  • Son, Jong-Duk;Shim, Min-Chan;Yang, Bo-Suk
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.8
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    • pp.872-878
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    • 2008
  • Many industrial operations require continuous or nearly-continuous operation of machines, interruption of which can result in significant cost loss. The condition monitoring of these machines has received considerable attentions in recent years. Rapid developments in semiconductor, computing, and communication with a remote site have led to a new generation of sensor called "smart" sensors which are capable of wireless communication with a remote site. The purpose of this research is to develop a new type of smart sensor for on-line condition monitoring. This system is addressed to detect conditions that may lead to equipment failure when it is running. Moreover it will reduce condition monitoring expense using low cost MEMS accelerometer. This system is capable for signal preprocessing task and analog to digital converter which is controlled by CPU. This sensor communicates with a remote site PC using TCP/IP protocols. The developed sensor executes performance tests for data acquisition accuracy estimations.

The Experience of Nursing Staff on the Dementia Patients′ Aggressive Behavior (간호제공자들의 치매노인 공격행동 경험에 대한 연구)

  • 오진주
    • Journal of Korean Academy of Nursing
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    • v.30 no.2
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    • pp.293-306
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    • 2000
  • Providing care to the dementia elderly with behavioral problem is a major issue in nursing homes today. This study was aimed to explore the nursing staffs′ response to aggressive dementia patients, and the effect that the aggressive behavior had on Nsgstaff. The interviews used a semi-structured questionnaire are were carried out from May to July, 1999. The subjects were 23 nursing personnel working in the nursing homes for dementia elderly. The result are as follows; 1. The types of aggressive behavior cited by the subjects was "physical", "linguistic", and "sexual". 2. The factors that caused the behavior were "symptoms of disease", "under- conditioning", "context of nursing care", "unsatisfied need", "relationship to other patients", "change of outer environment", and "invasion of one′s own privacy". 3. The response of the subjects were "unhappiness", "stress", "anger", "exaggeration", "anxiety", and "fear". 4. The management strategies listed by nursing personnel used to alleviate aggressive behavior were "ignorance" "patience" "leaving the area" "soothing sounds" "verbal punishment" "restriction and isolation" and "various management skill appliance" "adaptation". 5. The effect that aggressive behavior and were "disturbance of relationship to elderly" "decline in the amount and quality of nursing care" "interruption of task performance" "job exhaustion" "desire to leave the job" "physical impact" "stress on the cognition of others" "anxiety about health and one own future" "interference to family life′. The findings of this study will be useful in understanding the difficulties of nursing personnel when confronting the aggressive behavior of dementia partients. It also is useful as basic data in preparing efficient intervention program for these difficulties.

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Development of a CFD Program for Cold Gas Flow Analysis in a High Voltage Circuit Breaker Using CFD-CAD Integration (CFD-CAD 통합해석을 이용한 초고압 차단기 내부의 냉가스 유동해석 프로그램 개발)

  • Lee, Jong-Cheol;An, Hui-Seop;O, Il-Seong;Choe, Jong-Ung
    • The Transactions of the Korean Institute of Electrical Engineers B
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    • v.51 no.5
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    • pp.242-248
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    • 2002
  • It is important to develop new effective technologies to increase the interruption capacity and to reduce the size of a UB(Gas Circuit Breakers). Major design parameters such as nozzle geometries and interrupting chamber dimensions affect the cooling of the arc and the breaking performance. But it is not easy to test real GCB model in practice as in theory. Therefore, a simulation tool based on a computational fluid dynamics(CFD) algorithm has been developed to facilitate an optimization of the interrupter. Special attention has been paid to the supersonic flow phenomena between contacts and the observation of hat-gas flow for estimating the breaking performance. However, there are many difficult problems in calculating the flow characteristics in a GCB such as shock wave and complex geometries, which may be either static or in relative motion. Although a number of mesh generation techniques are now available, the generation of meshes around complicated, multi-component geometries like a GCB is still a tedious and difficult task for the computational fluid dynamics. This paper presents the CFD program using CFB-CAD integration technique based on Cartesian cut-cell method, which could reduce researcher's efforts to generate the mesh and achieve the accurate representation of the geometry designed by a CAD tools.

Delayed Intraventricular Nogo Receptor Antagonist Promotes Recovery from Stroke by Enhancing Axonal Plasticity

  • Kim, Tae-Won;Lee, Jung-Kil;Joo, Sung-Pil;Kim, Tae-Sun;Kim, Jae-Hyoo;Kim, Soo-Han
    • Journal of Korean Neurosurgical Society
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    • v.39 no.2
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    • pp.130-135
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    • 2006
  • Objective : After ischemic stroke, partial recovery of function frequently occurs and may depend on the plasticity of axonal connections. Here, we examine whether blockade of the Nogo/NogoReceptor[NgR] pathway might enhance axonal sprouting and thereby recovery after focal brain infarction. Methods : Adult male Sprague Dawley rats weighing $250{\sim}350g$ were used. Left middle cerebral artery occlusion[MCAO] was induced with a intraluminal filament. An osmotic mini pump [Alzet 2ML4, Alza Scientific Products, Palo Alto, CA] for the infusion of NgR-Ecto[310]-Fc to block Nogo/NgR pathway was implanted 1 week after cerebral ischemia. Prior to induction of ischemia, all animals received training in the staircase and rotarod test. Two weeks after biotin dextran amine injection, animals were perfused transcardially with PBS, followed by 4% paraformadehyde/PBS solution. Brain and cervical spinal cord were dissected. Eight coronal sections spaced at 1mm intervals throughout the forebrain of each animal with cresyl violet acetate for determination of infarction size. Images of each section were digitized and the infarct area per section was measured with image analysis software. Results : Histological examination at 11 weeks post-MCAO demonstrates reproducible stroke lesions and no significant difference in the size of the stroke between the NgR[310]Ecto-Fc protein treated group and the control group. Behavioral recovery is significantly better and more rapid in the NgR-Ecto[310]-Fe treated group. Blockade of NgR enhances axonal sprouting from the uninjured cerebral cortex and improves the return of motor task performance. Conclusion : Pharmacological interruption of NgR allows a greater degree of axonal plasticity in response this is associated with improved functional recovery of complicated motor tasks.

A Study on Application Structure for IT Operational Risk in Financial Institute (금융기관의 IT운영리스크 관점에서의 응용프로그램 구조에 관한 연구)

  • Cho, Seong-Cheol;Nam, Cho-Yee;Lee, Kyung-Ho
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.24 no.4
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    • pp.705-719
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    • 2014
  • Recently the importance of operational risk is gradually increasing in risk management of financial institute. Especially the service interruption caused by system failure can lead to customer complaints, decrease of profit and customer secession. Thus, financial industry makes diverse effort to minimize the impact caused by the system failure of IT application. Common modules are used in IT system in financial industry to exclude redundant development and to use the system efficiently. However, when a failure in common module is occurred, the risk that affects all the tasks using the common module exists. In this study, the damage affected by a failure in application program is prevented separating common module which has a large risk by task in the perspective of IT operational risk. In order to cope with damage, the research on the factors related to common module is conducted and proposes the separating common module standard for decrease of operational risk of the financial IT.

Simulator of Underwater Navigation

  • Waz, Mariusz
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.1
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    • pp.333-335
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    • 2006
  • Position of surface objects can be fixed in many ways. The most popular radionavigational systems, including satellite systems, make possible obtaining nearly continuous and very precise ship's position. However, under the water application of radionavigational systems is impossible. Underwater navigation requires other tools and solutions then these encountered in surface and air navigation. In underwater environment vehicles and submarines, operate that have to possess alternative navigational systems. Underwater vehicles, in order to perform their tasks require accurate information about their own, current position. At present, they are equipped with inertial navigational systems (INS). Accuracy of INS is very high but in relatively short periods. Position error is directly proportional to time of working of the system. The basic feature of INS is its autonomy and passivity. This characteristic mainly decides that INS is broadly used on submarines and other underwater vehicles. However, due to previously mentioned shortcoming i.e. gradually increasing position error, periodical calibration of the system is necessary. The simplest calibration method is surface or nearly surface application of GPS system. Another solution, which does not require interruption of performed task and emergence on the surface, is application of comparative navigation technique. Information about surrounding environment of the ship, obtained e.g. by means sonic depth finder or board sonar, and comparing it with accessible pattern can be used in order to fix ship's position. The article presents a structure and a description of working of underwater vehicle navigation system simulator. The simulator works on the basis of comparative navigation methods which exploit in turn digital images of echograms and sonograms. The additional option of the simulator is ability to robust estimation of measurements. One can do it in order to increase accuracy of position fixed with comparative navigation methods application. The simulator can be a basis to build future underwater navigation system.

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Policies to Manage Drug Shortages in Selected Countries: A Review and Implications (주요국의 수급불안정 의약품 관리제도에 관한 고찰과 한국에의 시사점)

  • Inmyung Song;Sang Jun Jung;Eunja Park;Sang-Eun Choi;Eun-A Lim;Sanghyun Kim;Dongsook Kim
    • Health Policy and Management
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    • v.34 no.2
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    • pp.106-119
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    • 2024
  • Drug shortage is a persistent phenomenon that poses a public health risk worldwide and occurs due to a range of causes. The purpose of this study is to review key policies to prepare for and respond to drug shortages in selected countries, such as the United States, Canada, and some European countries in order to draw implications. This study reviewed the reports and articles derived from search engines and Google Scholar by using keywords such as drug shortage and stock-out. Over the last decade or so, the United States have strengthened requirements on advance notification for disruption and interruption of drug manufacturing, established the Inter-agency Drug Shortages Task Force to promote the communication and coordination of responses, and expedited drug regulatory processes. Similarly, Canada established the Multi-Stakeholder Steering Committee on drug shortages by involving representatives from central and local governments and private sectors. Canada also adopted a tiered approach to the communication of drug shortages based on the assessment of the severity of the shortage problem and released a detailed information guide on communication. In 2019, the joint task force between the European Medicines Agency and the Heads of Medicines Agencies issued guidelines on drug shortage communication in the European Economic Area. The countries reviewed in this paper focus on communication across different stakeholders for the monitoring of and timely response to drug shortages. The efforts to protect public health from the negative impact of the drug shortage crisis would require multi-sectorial and multi-governmental coordination and development of guidelines.

Arithmetic Fluctuation Effect affected by Induced Emotional Valence (유발된 정서가에 따른 계산 요동의 효과)

  • Kim, Choong-Myung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.185-191
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    • 2018
  • This study examined the type and extent of interruption between induced emotion and succeeding arithmetic operation. The experiment was carried out to determine the influence of the induced emotions (anger, joy, and sorrow) and stimulus types (picture and sentence) on the cognitive process load that may block the interactions among the constituents of working memory. The study subjects were 32 undergraduates who were similar with respect to age and education parameters and were especially instructed to attend to induced emotion by imitation of facial expression and to make a correct decision during the remainder calculation task. In the results, the stimulus types did not exhibit any difference but there was a significant difference among the induced emotion types. The difference was observed in slower response time at positive emotion(joy condition) as compared with other emotions(anger and sorrow). More specifically, error and delayed correct response rate for emotion types were analysed to determine which phase the slower response was associated with. Delayed responses of the joy condition by sentence-inducing stimulus were identified with the error rate difference, and those by picture-inducing stimulus with the delayed correct response rate. These findings not only suggest that induced positive emotion increased response time compared to negative emotions, but also imply that picture-inducing stimulus easily affords arithmetic fluctuation whereas sentence-inducing stimulus results in arithmetic failure.