• Title/Summary/Keyword: lightening system

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Design Improvement for a Planetary Gear System in Hydraulic Drive System (굴삭기 유압 주행시스템의 복합유성기어 시스템 설계개선 연구)

  • Shin, Yoo In;Yoon, Chan Heon;Han, Sung Gil;Park, Seong Gyu;Song, Chul Ki
    • Journal of the Korean Society for Precision Engineering
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    • v.33 no.10
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    • pp.851-856
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    • 2016
  • Planetary gear systems have several advantages over traditional gearboxes with parallel axis gear shafts. The planetary gearbox arrangement also creates greater stability due to the even distribution of mass and increased rotational stiffness. However, gears in planetary gear systems occasionally have a short-life due to wear and breakage by repetitive load during operation time. In this study, we evaluated variables of the strength design for each part and conducted structural analysis of seven cases of the planetary gear system. The result of structural analysis was applied to shape optimization method and obtaining the weight lightening designed value. Subsequently, the planetary gear system was performed to ensure the durability of gears during operation time with miner's rule.

An Implementation of a u-Health Service Space Based on Sensor Network (센서 네트워크 기술에 기반한 유헬스 서비스 공간 구현)

  • Ahn, Si-Young;Lee, Tae-Young;Kim, Do-Won;Oh, Ha-Ryoung;Seong, Yeong-Rak;Park, Jun-Seok
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.35 no.2B
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    • pp.225-231
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    • 2010
  • In this paper, a sensor network system for providing u-health services is suggested and is implemented. It steadily collects biological data of resident people and automatically detects emergency situations. LEID (Lighting Embedded Information Device) nodes are the most essential component of the sensor network. They embed sensor network technology into lightening devices which are indispensable to most living spaces. To verify practicality of the proposed u-health system, a prototypical system is realized in the Smart Home Industrialization Support Center at Kookmin University, and is tested within many practical circumstances. The proposed u-health system can be used at various places where many patients are continuously cared.

Development of Thermal Management System Heater for Fuel Cell Vehicles (연료전지 자동차용 TMS 히터 개발)

  • Han, Sudong;Kim, Sungkyun;Kim, Chimyung;Park, Yongsun;Ahn, Byungki
    • Transactions of the Korean hydrogen and new energy society
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    • v.23 no.5
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    • pp.484-492
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    • 2012
  • The TMS(Thermal Management System) heater in a fuel cell vehicle has been developed to prevent a decline of fuel cell durability and cold start durability. Main functions of the COD(Cathode Oxygen Depletion) heater are depletion of oxygen in a cathode as heat energy and consumption of electric power for rapid warming up of a fuel cell stack. This paper covers subjects including the design specification of a heater, heater controller for detection of overheat and reliability assessment including coolant pressure cycle test of a heater. To verify the design concept, burst pressure and deformation analysis of plastic housing were carried out. Also, temperature distribution analysis of heater surface and coolant inside of housing were carried out to verify the design concept. By designing the plastic housing instead of a steel housing, the 30% weight lightening and 50% cost reduction were attained. A module-based design of a TMS system including a heater or reducing the watt density of a heater is a problem to be solved in the near future work.

Study on Hospital Environmental Causes Affected the Mother′s Comfort After Her Child Birth (산욕부 안위에 영향을 미치는 병원환경 요인에 관한 연구)

  • 변수자
    • Journal of Korean Academy of Nursing
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    • v.8 no.1
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    • pp.1-15
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    • 1978
  • The Purpose of this study is to examine closely the causes influenced upon the comfort and recovery of the woman delivered of a child in the hospital at the same time to understand environmental status of hospitals in order to promote mother's health recovery, and to improve hospital environment by emphasizing the meaning of environment and health before the medical staff and hospital administrative authority. In the method of servery of the research, 165 post paestum patients have been randomly selected who were accommodated and delivered their babies at OB(obstetric ) & GY (Gynecologic) unit the 7 general hospitals for the period of 6 December 1976 through 17 December 1976. As for the survey, it has been used of Questionnaire where we have 65 items in the respect of personal environment in the hospital such as trusting nurse, ability, reliability, kindness and etiquette of nurse and tile character of nurse the relationship with patients the other respect of physical environment included 9f temperature, moisture. air-ventilation lightening noise, cleanness. facilities, and the third realm being of mother's hearth ground to have the following conclusion 1. The feature of the collected personnel they are from OB or GY sects of from OB unit of the other 5 hospitals except the two general hospitals of the college or school Otherwise the rate of the patients to nurses would be 9 : 1. As for the nurses'ground it would be appeared of 20-25 years of age as the 76%. either 3 year course or 4 year course in the education would be each 50% and less than 2 year experience case would record as of 60 %. In the respect of hospital physical environmental status, there we have two hospitals without any thermometers, on the other han4 nowhere there's hygrometer, otherwise, the lightening is normal or over than normal As for the structure of noise protection the corridors're, generally speaking worse than rooms, nerver hueless, there's no ventilating system in the hospitals. The rooms'repainted in white and yellow, light green white, or green color. The patient's clothing were in green pink blue, light green or in white co for. There're not anything special in both decoration and equipments. Most of them used tall beds except in one hospital 2. To the extent of perception of patient's hatch 9round and hospital environment it is presented that they perceived nurse's ability in highest in total human variable, though perceived kindness or etiquette in the lowest otherwise, comparatively high in total average. 3. In the respect of physical environment it is highest perceived of lightening terms, otherwise, lowest perceived of air ventilation and total average became lowest than the one of the original record 4. To ages, in the respect of hatch ground rather old aged mother than the younger one has perceived that nurse would be trusting, in good service character, able, at the same time, liable, Otherwise, in physical environment regardless of age, they perceived lightening in high and remarkably lower in ventilation As a result of the examination of the difference in hospital environment to each age it is appeared of statistical difference at 5% level of ability in the personal environment otherwise little difference as for physical environment 5. In the respect of perceiving level to educational standard it is highly perceived of personal environment for higher ranking group rather than lower group in the educational standard. In case of physical environment it is highly perceived for lower level group rather than higher level group in educational background. The variables which have statistical significance at 5% level are from trusting kindness, etiquette and total kindness, etiquette and total all significance at 5% level are from trusting, kindness, etiquette and total human environment variable in personal environment, otherwise, there's little difference in the physical environment. 6. The perceiving level due to times of admission and accommodation at the hospital would be cleared out as gradual higher perception both physical and personal environment in the hospital. At 5% significant level of the ventilation condition in physical environmental variable it is presented of meaningful difference otherwise, there we have little difference both in Personal variable and other one. 7. In accordance with living standard, the perception degree of personal environment in tee hospital would be inclined to increase to higher living standard on the other hand, in case of the physical environment, the perception level world increase to lower living standard At 5 % level, the trustuariable and total scores in the personal eicuironmectal variable there appeared a meaningful/ significant difference otherwise, there presented little difference both in physical environmental and other variable to the living standard 8. Pertaining to family unit, the mother of an independent family unit perceived highly in all respect of the personal and the physical environment in the hospital rather than the woman of succeeding family unit. At 5 % level there appeared a difference in the respect of kindness and etiquette both in personal environment variable, on the other hand, there hardly marked a difference between other variable and physical environmental one. 9. The degree of perception to comforting level has little connection with a statistical difference the age, educational level hospital admitting times, living standard or family unit. 10. The most effective variable to mother's comforting level will be nurse's ability, reliability, trusting manner, and total physical environment variable in order.

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Impulse Characteristics of MOV Elements for Railroad Vehicle Arrester (전철 탑재 피뢰기용 MOV 소자 임펄스 특성)

  • Han, S.W.;Cho, H.G.;Lee, H.G.
    • Proceedings of the KIEE Conference
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    • 1999.07d
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    • pp.1529-1531
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    • 1999
  • The main functions of AC railroad vehicles arresters is to protect the main transformer from lightening impulse or switching impulse surge, then the MOV(metal oxide varistor) elements rated of 10kA is applied. The residual voltage and surge energy absorption are important parameters in designing arrester, these must be carefully decided with considering protecting level of impulse environment of system. The purpose of this study is to discuss the residual voltages and the energy absorption capability by impulse currents on MOV elements for railroad vehicles, and to introduce design factors which act as optimal protecting condition against impulse currents.

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Gabor-Features Based Wavelet Decomposition Method for Face Detection (얼굴 검출을 위한 Gabor 특징 기반의 웨이블릿 분해 방법)

  • Lee, Jung-Moon;Choi, Chan-Sok
    • Journal of Industrial Technology
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    • v.28 no.B
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    • pp.143-148
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    • 2008
  • A real-time face detection is to find human faces robustly under the cluttered background free from the effect of occlusion by other objects or various lightening conditions. We propose a face detection system for real-time applications using wavelet decomposition method based on Gabor features. Firstly, skin candidate regions are extracted from the given image by skin color filtering and projection method. Then Gabor-feature based template matching is performed to choose face cadidate from the skin candidate regions. The chosen face candidate region is transformed into 2-level wavelet decomposition images, from which feature vectors are extracted for classification. Based on the extracted feature vectors, the face candidate region is finally classified into either face or nonface class by the Levenberg-Marguardt back-propagation neural network.

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Use of Geographic Information System Tools for Improving Atmospheric Emission Inventories of Biogenic Source

  • Shin, Tae-joo
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.3 no.3
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    • pp.151-158
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    • 1999
  • Biogenic source emissions refer to naturally occuring emissions from vegetation, microbial activities in soil, lightening, and so on. Vegetation is especially known to emit a considerable amout of volatile organic compounds into the atmosphere. Therefore, biogenic source emissions are an important input to photochemical air quality models. since most biogenic source emissions are calculated at the county-level, they should be geographically allocated to the computational grid cells of a photochemical air quality model prior to running the model. The traditional method for the spatial allocation for biogenic source emissions has been to use a "spatial surrogate indicator" such as a county area. In order to examine the applicability of such approximations, this study developed more detailed surrogate indicators to improve the spatial allocation method for biogenic source emissions. Due to the spatially variable nature of biogenic source emissions, Geographic Information Systems(GIS) were introduced as new tools to develop more detailed spatial surrogate indicators. Use of these newly developed spatial surrogate indicators for biogenic source emission allocation provides a better resolution than the standard spatial surrogate indicator.indicator.

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Seoul World Cup Stadium Electric Plan (서울월드컵경기장 전기설계)

  • 최용민
    • Journal of the Korean Professional Engineers Association
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    • v.34 no.5
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    • pp.40-43
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    • 2001
  • In order for the World cup football game to be operated stably with duplicate service electric power supply, It is done, emergency generator and the U.P.S it establishes. the electric power system power control, lighting control, integrated monitoring. rue fighting. obstruction light, the searchlight, snow melting, electric erosion shield. grounding, the lightening protection and viewable lighting, stadium floodlight and an electric bulletin board it composed of the back which it sells.

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A New Approach to the High Efficiency of Hydraulic Excavator (유압식 굴삭기의 고효율 화에 관한 새로운 접근)

  • Lee, Y.B.
    • Journal of Drive and Control
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    • v.11 no.4
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    • pp.39-45
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    • 2014
  • With recent oil price increases, the fuel efficiency of hydraulic excavators has become a serious issue. Researchers have considered weight lightening by high pressurization in order to improve the efficiency of the excavator and pump controlled actuation (PCA) and to reduce pressure loss of hybrid and valves using mechanical inertia. However, high pressurization is not very effective because the excavator operates at a low speed; a hybrid is inefficient because little accumulated inertial energy is accumulated; and PCA is ineffective because control precision and responsibility are low. In this study, a method to minimize air and gas in hydraulic oil has been presented as a simple and new way to increase hydraulic efficiency.

A Design of On/Off Type Solenoid Actuator for Valve Operation (밸브 구동용 개폐식 솔레노이드 액추에이터의 설계)

  • Sung, B.J.
    • Transactions of The Korea Fluid Power Systems Society
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    • v.6 no.4
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    • pp.24-32
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    • 2009
  • For a design of on/off solenoid actuator for valve actuating, designer must have the experimental knowledge as well as general electromagnetic formulas to design object. It is possible for theoretical knowledge to do the out-line design, but it is impossible to optimal design without experimental knowledge which only can be achieved through many repeated experiments. In addition, in present on/off type solenoid actuator field, the smaller, lightening, lower consumption power, high response time are effected as the most important design factor. So, experimental knowledge is more needed for optimal design of solenoid actuator. In this study, we derived the governing equations for optimal design of on/off solenoid actuator for valve actuating and developed a design program composed electromagnetic theories and experimental parameter values for inexperienced designers. And we proved the propriety of this program by experiments.

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