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Study on the Need for the Family Life Education among the Middle Aged Wives (중년기 주부의 가족관계향상을 위한 가족생활교육 요구도 분석)

  • 김명자
    • Journal of the Korean Home Economics Association
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    • v.36 no.3
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    • pp.61-76
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    • 1998
  • The Purpose of this paper is to find out the middle aged wives need for the family life education(FLE). The data were collected from 317 middle aged wives who's last child age over-18th. 1. The need for the FLE is indicated at the middle level, and we can see the strongest need of the being educated about the parent-child relationship, and of the being educated about the wife itself, about the older parent relationship and about the spousal relationship by turn. 2. Wife's age, husband's age, duration of marriage, income, number of children, type of family have a significant influence on the need for the family life education. 3. The middle aged wives want to educate about emotional control of leaving child, economic stability, teaching their child about value of marriage, and prevention and care of dementia. 4. This paper proposes that we should develope and execute not only the program of the FLE with respect to enough the need of the being educated, but also the programs of education about the grand parent role because of the increasing of the number of old aged people.

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Development of Contents Syndication Systems for Engineering Information Management in Semi-conductor Industries (반도체 산업의 공학 정보 관리를 위한 컨텐츠 신디케이션 시스템의 개발)

  • Kim, Tae-Yoon;Koo, Sang-Hoe
    • Journal of Information Technology Applications and Management
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    • v.13 no.4
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    • pp.109-120
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    • 2006
  • Enterprise Content Integration (ECI)is an IT strategy that improves enterprise' competitive advantages by integrating enterprise wide information and content into a unified view, which in turn supports efficient and effective decision making. Content Syndication Systems (CSS) is a solution that implements the ECI strategy. In semi-conductor industries, it is usual that enterprise content is scattered over tens of legacy systems. Therefore, engineers in semi-conductor companies spend a few hours to locate required engineering information on a daily basis as part of their jobs. In this paper, we develop an enterprise CSS system that integrates enterprise wide contents into a unified view that is suitable for semi-conductor industries. For this research, we first define enterprise CSS, then identify their systems requirements. Then we propose an architecture supporting the identified requirements, and present the implemented prototype. One of the most important requirements is the individualized subscription rule setting for engineering information. For this purpose, we developed methods to represent the information properties and subscription rules.

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Analysis on the Switching Surge Characteristics of a High-Voltage Induction Motor Fed by PWM Inverter Using EMTP

  • Kim Jae-Chul;Song Seung-Yeop;Lee Do-Hoon
    • KIEE International Transactions on Power Engineering
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    • v.5A no.1
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    • pp.22-30
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    • 2005
  • The PWM inverter drive may cause an over voltage at the motor terminal, which imposes severe electric stresses on the inter-turn insulation of motor windings. Unlike low-voltage induction motors, high-voltage induction motors have a stator type of form-wound coil for insulation and are insulated to the slot and the coil. So, this paper presents a PWM 3-level inverter, H-Bridge cascaded 7-level inverter and High-voltage induction motor model. It then analyzes the voltage that generates at the input terminal of the high-voltage induction motor fed by each inverter. Also, in order to examine a factor that influences the switching surge voltage, this paper proposes the system equivalent model and performs the case studies using EMTP.

Fuse Protection of IGBT Modules against Explosions

  • Blaabjerg, Fred;Ion, Florin;Ries, Kareten
    • Journal of Power Electronics
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    • v.2 no.2
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    • pp.88-94
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    • 2002
  • The demand for protection of power electronic application has during the last couple of vears increased regarding the high-power IGBT modules. Even with an active protection, a high power IGBT still has a risk of exhibiting a violent rupture in the case of a fault if IGBT Fuses do not protect it. By introducing fuses into the circuit this will increase the circuit inductance and slight inductance over-voltage during the turn-off of the diode and the IGBT. It is therefore vital when using fuses that the added inductance is kept at a minimum. This paper discuss three issues regarding the IGBT Fuse protection of adding inductance of existing High-speed and new Typower Fuse protection. First, the problem of adding inductance of exiting High-speed and new Typower Fuse DC-link circuit is treated, second a short discussion of protection of the IGBT module is done, and finally, the impect of the high frwquency loading on the currying capability of the fuses is presented.

Study on enhancing the filter transfer-function using the Secant method (시컨트 방법을 이용하는 여파기 전달 특성 개선에 관한 연구)

  • Ju, Jeong-Ho;Kahng, Sung-Tek
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.258-259
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    • 2007
  • In this paper, the secant method is adopted to improve a transfer function required by specific filtration properties. It is advantageous over the conventional and widely used 'Template method' in that it enables users to seek the position of a pole which will turn out to meet well the requirements of in-band insertion loss as well as stop-band rejection even after a small number of iterative steps. For validating the proposed method, the transfer function of a 4-pole waveguide filter is targeted.

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Flyback-type Snubber of High Efficiency for 10kV IGCT in 7MW Wind Turbine Systems

  • Shirmohammadi, Siamak;Suh, Yongsug
    • Proceedings of the KIPE Conference
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    • 2015.07a
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    • pp.359-360
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    • 2015
  • 10kV IGCT has been recently developed and has the potential to push wind turbine systems to higher power and voltage rating. Converters employing IGCTs need snubber and OVP circuit to limit the rate of rise of current and peak over voltage across IGCT during turn on and off state respectively. The conventional RCD snubber which is used in such power converter dissipates a significant amount of power. In order to reduce the amount of energy lost by conventional RCD snubber, this paper proposes an isolated inductor snubber circuit that not only meets all of the IGCTs characteristics during on and off-state but also significantly saves the power loss. Loss analysis of conventional di/dt snubber and OVP circuit is performed for the 3-level NPC type back-to-back VSC supplied from grid voltage of 6.9kV. In comparison with the conventional snubber, isolated inductor snubber has a fewer number of components and improved efficiency leading to a reliable and efficient wind turbine systems.

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Design of Fuzzy PI Controller for Piezo Actuator of Nano Stage (나노 스테이지용 압전 구동기의 퍼지 PI 제어기 설계)

  • Cho, Seong-Yeon;Chung, Chung-Choo
    • Proceedings of the KIEE Conference
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    • 2003.11c
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    • pp.629-632
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    • 2003
  • Piezo actuators are mainly used in precision position control system because of their high position resolution. Although there have been many approaches in open loop control of this, those method turn out to be not effective in precision control due to hysteresis and creep. To overcome the problems, closed loop PI control method is used in commercial products. However, it is very difficult to obtain fast response with conventional PI control although piezo actuator has fast response. In this paper, we propose a fuzzy PI control method with the proposed fuzzy PI controller, we obtains faster settling response over the conventional PI controller. We verify the effectiveness of the proposed method with experimental results.

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Impact of Quantitative Feeding on Nutritional Parameters of Fifth Instar Larvae of Antheraea mylitta

  • Rath, Sudhansu Sekhar
    • International Journal of Industrial Entomology and Biomaterials
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    • v.20 no.2
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    • pp.69-74
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    • 2010
  • Feeding is an important aspect of insect nutrition which in turn supports growth, development, reproduction and survival. The impact of quantitative feeding on nutritional parameters of fifth instar Antheraea mylitta larvae was studied by providing fresh leaves of Terminalia tomentosa for 1 to 4 times a day. All the parameters improved upon providing fresh diets more times over the single diet (1FD). The absolute body weight increased with increase in number of feeds/day significantly (P<0.001). While the maximum weight recorded was 29.61 g in 1FD, the respective weights for two feeds/day (2FD), three feeds/day (3FD) and four feeds/day (4FD) were 39.41 g, 40.63 g and 42.66 g respectively. Feeding period and instar duration were declined (P<0.001) and survival increased significantly (P<0.001) upon increase in the number of diets. Nutritional indices like ingestion, digestion, relative consumption rate (RCR), relative growth rate (RGR) and gain in body weight increased significantly with the increase in number of feeds/day, but approximate digestibility (AD) and efficiency of conversion of ingested food (ECI) declined, while efficiency of conversion of digested food (ECD) did not change.

Variation of Microstructure and Hardness of Contact Tips during GMA Welding (GMA용접 중 콘택트팁의 미세조직과 경도변화)

  • 김남훈;김가희;김희진;유회수;고진현
    • Journal of Welding and Joining
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    • v.22 no.1
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    • pp.43-49
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    • 2004
  • Contact tip is located so near to welding arc that it is heated to high temperature during long time welding. In such a situation, tip changes in its microstructure and in turn its mechanical properties. This study was intended to investigate those changes by using simulated heat treatment. As a result of this study, it was confirmed that tip of Cu-P alloy hardened with severe cold deformation lose its initial hardness to a large extent within 60 min due to the occurrence of rapid recrystallization while that of Cu-Cr composition hardened by proper aging treatment can preserve its intial hardness for about 1,000 min or longer. Based on these results, suggested was a guideline that can classify contact tips into two different grades: deformation-hardened type and precipitation-hardened type. Following a guideline, a tip with Cu-Cr composition can be classified into the deformation-hardened type if it is in the over-aged condition. Such a guideline is well described.

Foodservice Employee Job Satisfaction in 14 Hospital Food Service Systems (병원 급식종사원의 직무만족도에 관한 연구)

  • Hong, Wan-Soo
    • Korean journal of food and cookery science
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    • v.10 no.3
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    • pp.296-300
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    • 1994
  • Recently hospital food service systems are often burdened with labour problems including employee job dissatisfaction, high labour costs and turn over. It is essential that these factors should be considered in developing for assuring palatable, nutritious, and safe feeding. A survey of 14 hospital conventional food service systems was undertaken and detailed information was collected from 390 catering staff. Foodservice employee satisfaction was evaluated by measuring employee job attitudes towards five aspects of their job using the Job Description Index(JDI). The food serive workers surveyed in this research were less satisfied with their jobs than are other types of workers in other industries. The demographic variables including age, length of employment and kinds of work were significantly related to job satisfaction. It was also found that catering staff in 14 hospitals surveyed were more satisfied with their interpersonal relations with supervisions and co-workers than with work content, pay and promotional opportunities.

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