• 제목/요약/키워드: inexpensive

검색결과 1,271건 처리시간 0.032초

온도특성을 고려한 착자회로 및 요크의 특성 해석 (Characteristics Analysis of Magnetizing Circuit and Fixture considering Temperature Characteristic)

  • 백수현;맹인재;김필수;김철진
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 정기총회 및 추계학술대회 논문집 학회본부
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    • pp.82-84
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    • 1993
  • A method for simulating general characteristics and temperature characteristics of magnetizing fixture coil of the capacitor discharge impulse magnetizer-magnetizing fixture system using SPICE is presented. This method has been developed which can aid the design, understanding and inexpensive, time-saving of magnetizing circuit. As the detailed characteristics of magnetizing circuit can be obtained, the efficient design of the magnetizing circuit which produce desired magnet will be possible using our SPICE modeling. Especially, The knowledge of the temperature of the magnetizing fixture is very important to forecast the characteristics of the magnetizing circuits tinder different conditions. The capacitor voltage was not raised above 810[V] to protect the magnetizing fixture from excessive heating. The temperature estimation method uses multi-lumped model with equivalent thermal resistance and thermal capacitance.

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IEC 코드 기반의 뉴로-퍼지모델을 이용한 유입변압기 고장진단 기법 (A Fault Diagnosis Method of Oil-Filled Power Transformers Using IEC Code based Neuro-Fuzzy Model)

  • 서명석;지평식
    • 전기학회논문지P
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    • 제65권1호
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    • pp.41-46
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    • 2016
  • It has been proven that the dissolved gas analysis (DGA) is the most effective and convenient method to diagnose the transformers. The DGA is a simple, inexpensive, and non intrusive technique. Among the various diagnosis methods, IEC 60599 has been widely used in transformer in service. But this method cannot offer accurate diagnosis for all the faults. This paper proposes a fault diagnosis method of oil-filled power transformers using IEC code based neuro-fuzzy model. The proposed method proceeds two steps. First, IEC 60599 method is applied to diagnosis. If IEC code can't determine the fault type, neuro-fuzzy model is applied to effectively classify the fault type. To demonstrate the validity of the proposed method, experiment is performed and its results are illustrated.

영상 초점을 이용한 물체의 표면 굴곡도 측정 (Finding Surface Roughness of Materials using Image Focus)

  • 심성오;아미르;최태선
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2008년도 하계종합학술대회
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    • pp.907-908
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    • 2008
  • Estimation of surface roughness is an important quality measure for many applications including optics, polymers, semiconductor etc. In this paper, we propose to estimate surface roughness using image focus. We use polymers as test objects. The proposed method is an inexpensive and fast method based on Shape From Focus (SFF). We show that the results from SFF are encouraging for comparison of polymers using surface roughness.

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비취업 기혼 여성의 취업의사와 영향요인 분석 (The Possibility of Unemployed Married Women's Entering into the Labor Market)

  • 김혜연
    • 대한가정학회지
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    • 제35권2호
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    • pp.81-94
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    • 1997
  • The purpose of this study is to identify the possibility of unemployed married women's economic activity by analysing their willingness to work and possible influencial factors on it. This study estimates the effects of independent variables on the dependent available by using Binomial Probit Model. sample are 592 two-parent households. The results of this study are as follows ; The percentage of unemployed married women's willingness to enter into the labor market is 25.2%. Among the variables which have affected their willingness are family variables(family size, the number of children and the existence of children under the age of 6), personal variables(the age, education level and the past working experience) and financial variables(non-wage income, Engel's coefficient, expenditure o leisure activities and the subject judgement of their financial status). It is hard to accept those women's low willingness as is since the most crucial statistically was especially the children of 6 or less among the family variables. That is to say, more favorable conditions of the labor market and inexpensive day-care centres available would certainly encourage married women to be more willing to participate in economic activities as employees.

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PC 클러스터 상에서 분자동역학을 이용한 파괴 모사 (Facture Simulation using Molecular Dynamics on a PC Cluster)

  • 최덕기;류한규
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2001년도 추계학술대회논문집A
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    • pp.252-257
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    • 2001
  • With the help of newly arrived technology such as PC clustering, molecular dynamics (MD) seems to be promising for large-scale materials simulations. A cost-effective cluster is set up using commodity PCs connected over Ethernet with fast switching devices and free software Linux. Executing MD simulations in the parallel sessions makes it possible to carry out large-scale materials simulations at acceptable computation time and costs. In this study, the MD computer code for fracture simulation is modified to comply with MPI (Message Passing Interface) specification, and runs on the PC cluster in parallel mode flawlessly. It is noted that PC clusters can provide a rather inexpensive high-performance computing environment comparing to supercomputers, if properly arranged.

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Detection of Pathogenic Yersinia enterocolitica Strains by a Rapid and Specific Multiplex PCR Assay

  • Kim Young-Sam;Kim Jong-Bae;Eom Yong-Bin
    • 대한의생명과학회지
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    • 제10권4호
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    • pp.333-339
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    • 2004
  • A multiplex PCR assay targeting the yst and 16S rRNA genes of Yersinia enterocolitica was developed to specifically identify pathogenic Y. enterocolitica from pure culture. Simultaneous amplification of 145 and 416 bp fragments of the yst and 16S rRNA genes of Y. enterocolitica was obtained using the primer pairs in a single reaction. Validation of the assay was performed with the reference Yersinia strains and other members of the family Enterobacteriaceae. The defined primer pairs amplified the targeted sequence from only pathogenic Y. enterocolitica strains, whereas none of the other bacterial species yielded any amplified fragments. Within an assay time of 4 h, this assay offers a very specific, reliable, and inexpensive alternative to the conventional phenotypic assays used in clinical laboratories to identify pathogenic Y. enterocolitica.

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Intelligent Switching Control of Pneumatic Cylinders by Learning Vector Quantization Neural Network

  • Ahn KyoungKwan;Lee ByungRyong
    • Journal of Mechanical Science and Technology
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    • 제19권2호
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    • pp.529-539
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    • 2005
  • The development of a fast, accurate, and inexpensive position-controlled pneumatic actuator that may be applied to various practical positioning applications with various external loads is described in this paper. A novel modified pulse-width modulation (MPWM) valve pulsing algorithm allows on/off solenoid valves to be used in place of costly servo valves. A comparison between the system response of the standard PWM technique and that of the modified PWM technique shows that the performance of the proposed technique was significantly increased. A state-feedback controller with position, velocity and acceleration feedback was successfully implemented as a continuous controller. A switching algorithm for control parameters using a learning vector quantization neural network (LVQNN) has newly proposed, which classifies the external load of the pneumatic actuator. The effectiveness of this proposed control algorithm with smooth switching control has been demonstrated through experiments with various external loads.

마이크로컴퓨터를 이용한 온-라인 측정 시스템의 개발 (Development of microcomputer-based on-line measurement system.)

  • 정명균;이정운
    • 대한기계학회논문집
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    • 제5권4호
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    • pp.274-283
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    • 1981
  • An inexpensive and very simple microcomputer-aided measurement system has been designed for on-line experiments, which perform simultaneously data acquisition, data recorditing, calculations with the data, and positioning of necessary sensors. Interfacting between the microcomputer and the data acquisition board which consists of A/D converter, analog multiplexer, and sample-and-holder, etc. has been done through IEEE-488 interface port and parallel user port both provided by the PET computer's main logic board. Data and control signals are transfered between devices without handshaking. By utilizing BASIC commands PEEK, POKE, SYS, USR which are offered by PET microcomputer, it is possible to link machine code subroutines into the main BASIC program. This facilitates ease of data transfer, programming, and speedy execution of the program. In addition, an X-Y scanning table has been concected to the system in order to automatically position measuring sensors along a pre-determined path of interest.

LVQNN을 이용한 공압 로드리스 실린더의 고정도 위치제어 (High accuracy position control of pneumatic rodless cylinder using LVQNN)

  • 표성만;정민화;안경관;이병룡;양순용
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2003년도 춘계학술대회 논문집
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    • pp.1012-1017
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    • 2003
  • The development of a fast, accurate, and inexpensive position-controlled pneumatic actuator that may be applied to a variety of practical positioning applications with various external loads is described in this paper. A novel modified pulso width modulation (MPWM) valve pulsing algorithm allows on/off solenoid valves to be used in place of costly servo valves. A comparison between the system response of standard PWM technique and that of the novel modified PWM technique shows that the control performance is significantly increased. A state feedback controller with position, velocity and acceleration feedback is successfully implemented as the continuous controller. Switching algorithm of control parameter using learning vector quantization neural network (LVQNN) is newly proposed. which estimates the external loads of the pneumatic actuator. The effectiveness of the proposed control algorithms are demonstrated through experiments with various loads.

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Soft Fault Detection Using an Improved Mechanism in Wireless Sensor Networks

  • Montazeri, Mojtaba;Kiani, Rasoul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권10호
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    • pp.4774-4796
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    • 2018
  • Wireless sensor networks are composed of a large number of inexpensive and tiny sensors used in different areas including military, industry, agriculture, space, and environment. Fault tolerance, which is considered a challenging task in these networks, is defined as the ability of the system to offer an appropriate level of functionality in the event of failures. The present study proposed an intelligent throughput descent and distributed energy-efficient mechanism in order to improve fault tolerance of the system against soft and permanent faults. This mechanism includes determining the intelligent neighborhood radius threshold, the intelligent neighborhood nodes number threshold, customizing the base paper algorithm for distributed systems, redefining the base paper scenarios for failure detection procedure to predict network behavior when running into soft and permanent faults, and some cases have been described for handling failure exception procedures. The experimental results from simulation indicate that the proposed mechanism was able to improve network throughput, fault detection accuracy, reliability, and network lifetime with respect to the base paper.