• Title/Summary/Keyword: Mass changes

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Service Identification for Service Science (서비스 사이언스를 위한 서비스의 식별)

  • Lee, Sang-Joon
    • Journal of Information Technology Services
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    • v.6 no.3
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    • pp.209-224
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    • 2007
  • Currently, the world has experienced a mass exodus of workforce from the manufacturing industry to service related industry. In addition, the changes of industry structure toward service industry have been gradually accelerated. We have felt that it is time to conduct researches about IT service systematizing and discovering the essence of service itself with scientific and synthetic ways based on Service Science. For Service Science researchers, service identification is regarded as a difficult activity when they contact it for the first time and they want to apply it real environment. In reality, there exist mismatches between business and IT service to identify service since service is identified from the business point of view in Service Science area and it is identified from the technical point of view in IT service area. In this paper, we have conducted researches about service identification placed on the first priority and regarded as difficult area in service-oriented business area. To lessen aforementioned difficulties, we propose procedures and methods for extracting and identifying service in the viewpoint of business process. We conducted case study and comparison with existing researches to verify the applicability and the excellence of our proposal.

Flow analysis of the Hydrogen Recirculation System for Fuel Cells (연료전지 수소 재순환 시스템의 유동해석)

  • Kim, Jae-Choon;Lee, Yong-Taek;Chung, Jin-Taek;Kim, Yong-Chan;Hwang, In-Chul
    • 유체기계공업학회:학술대회논문집
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    • 2005.12a
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    • pp.759-764
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    • 2005
  • In this paper, numerical analysis of hydrogen recycle system has been conducted in order to enhance the efficiency of automotive fuel cell. Generally, the excess hydrogen is provided in the automotive fuel cell. Since the non-reaction hydrogen reduces automotive fuel cell efficiency, reuse of the non-reaction hydrogen can be helpful to improve the fuel cell performance. In case of PEM FC, the water vapor is provided to hydrogen from the cathode so that the mixture experiences phase change depending on the changes of pressure and temperature. The internal flow of the mixture in the hydrogen recirculation system of fuel cell was investigated for real flow conditions. The variation of performance, properties and mass fractions of mixture, hydrogen and water-vapor were investigated. This study was performed based on 80KW level automotive fuel cell's recycling system.

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The impact of climate change on the European Alps : Artificial snow and environmental problems (긴급제언 - 유럽알프스지역의 기후변화 영향 : 인공설(雪)과 환경문제)

  • Lee, Yeong-Heui
    • Journal of the Korean Professional Engineers Association
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    • v.45 no.2
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    • pp.28-32
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    • 2012
  • The European Alps face a number of major threats - from habitat loss to pollution, from mass tourism to the impacts of climate change. The European alpine climate has changed significantly during the past century, with temperatures increasing more than twice the global average. This makes alpine mountains especially vulnerable to changes in the hydrological cycle and decreases in snow and glacier cover, which are already occurring. In winter, artificial snow-making is currently the most widespread strategy to extend and supplement natural snow cover and secure winter tourism. Artificial snow-making is not only very costly, but also has knock-on effects such as increased water consumption and energy demand or ecological damage, which may lead to negative externalities. The European Alps facing the challenge of changing climate and anthropogenic pressures.

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Effect on body composition change during 6 weeks of aerobic and circuit weight training (6주간의 유산소성 및 근력강화운동이 체성분 변화에 미치는 영향)

  • Hwang, Eui-Hyoung;Kim, Jeong-Yeon
    • The Journal of Korea CHUNA Manual Medicine
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    • v.6 no.1
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    • pp.11-20
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    • 2005
  • Objectives: To find relation with training period and body composition of peoples engaged in training program of six weeks and present a better training formula. Methods: Changes of body composition during training were analysed with paired t-test. correlation of training period and body composition were analysed with simple correlation analysis. Results: Body weight, body fat and body fat ratio were decreased significantly, all of them were concerned in training period. Conclusions: Training program of six weeks reduce body weight, body fat ratio even muscle mass. It should be careful to order training prescription.

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Diet Composition of Japanese Tree Frog (Hyla japonica) in a Rice Paddy, South Korea

  • Park, So Hyun;Lee, Hyun;Cho, Kang-Hyun
    • Ecology and Resilient Infrastructure
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    • v.5 no.1
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    • pp.54-58
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    • 2018
  • Diet composition of amphibians usually reflects the distribution of potential prey within habitats, as well as their diet preference. We identified the diet items of Japanese tree frog (Hyla japonica) using a stomach flushing method in a rice paddy for the establishment of bio-monitoring systems of landscape changes. During the reproductive period, 71% of calling males had empty stomachs. All prey items in the stomachs belonged to the phylum Arthropoda, from eight orders of Insecta and one order of Arachnida. Among insect prey, the most common items in the stomachs were adults of beetles, flies and bugs, and larvae of butterflies and moths. There was a significant positive correlation between the body mass of Japanese tree frogs and the volume of prey items. Our results can provide a basic framework to guide the monitoring systems using prey identification of Japanese tree frogs.

Comparison of explosive compounds (HMX, RDX, and TNT) reduction by micro and nano zero valent iron

  • Bae Beom-Han
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2006.04a
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    • pp.123-126
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    • 2006
  • Reduction kinetics and intermediates behaviour of three high explosives (HMX, RDX, and TNT) were studies in batch reactors using either nano or micro size zero valent iron(ZVI) as reducing agent. The kinetics constants normalize to the mass of iron($k_M$) or to the surface area ($k_{SA}$) were measured and compared along with the changes of intermediate concentrations of each explosive. Results showed that $k_M$ and $k_{SA}$ values neither correlated each other nor explained the behaviour of intermediates of each high explosive in the batch reactor, in which initial intermediates decreased rapidly with nano ZVI treatment whereas the intermediates accumulated and stayed longer in the micro ZVI treated reactor.

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An Active Simulation of Long Spindle with Static Droop (정적 처짐을 고려한 초장축 스핀들의 동적시뮬레이션)

  • Chung W.J.;Lee C.M.;Park K.B.;Kim J.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.451-452
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    • 2006
  • According to the demand of high productivity, the interest of manufacturing skills is growing in the industrial society. Especially the long spindle becomes important these days. The rotating accuracy of the spindle concerns the centrifugal force. In detail explaining, it is influenced by the speed of the spindle. In this study, we would show changes of the distance caused by a rotating speed of the spindle using a software, $ADAMS^{(R)}$. And because of the gravity of the spindle's mass, we would find the static droop of the long spindle.

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The Evaluation on The Effect of Communication and Shared Knowledge Between IS and Line Organizations to IS Performance (IS 조직과 라인 조직간의 의사소통 및 공유지식이 IS 성과에 미치는 영향에 관한 연구)

  • Kym, Hyo-Gun;Pyo, Jie-Hyun;Choi, In-Young
    • Asia pacific journal of information systems
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    • v.13 no.1
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    • pp.197-211
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    • 2003
  • Intensified competition, splintered mass market, shortened product life cycles, and advanced technology and automation let companies to crease the IT investment to meet the changes, Although IT investment increased, IS didn't show the visible outcome. One of the major interest of IS managers is how to demonstrate the business value of the firm's investment in information technology. This paper proposes the revised model of Nelson & Cooprider(1990) regarding shared knowledge between IS and line groups. Knowledge can be shared through mutual trust, mutual influence and communication between these two groups. The revised model including communication is tested empirically using LISREL. The results show that shared knowledge mediated the relationship between IS performance and mutual trust, mutual influence and communication. And shared knowledge between IS and line groups increase IS performance. IS managers should develop mutual trust, mutual influence and communication between these groups to achieve more shared knowledge and higher IS performance.

A Case of Primary Hyperparathyroidism with Thyroid Adenoma (갑상선 선종을 동반한 원발성 부갑상선 기능 항진증 1예)

  • Jung Sung-Hoo;Kim Wan-Cheol;Kang Nam-Poo
    • Korean Journal of Head & Neck Oncology
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    • v.15 no.1
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    • pp.80-84
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    • 1999
  • Primary hryperparathyroidism is a relatively rare disease entity in Korea. It's characterized by severe skeletal and renal changes due to hypersecretion of parathyroid hormone, and rarely shows peptic ulceration, hypertension, pancreatitis and impaired mentality. Recently the determination of the serum calcium level has become a routine laboratory test and the awareness of primary hyperparathyroidism has been incerased, the disease is being diagnosed with increasing frequency. Primary hyperparathyroidism is most commonly caused by parathyroid adenoma and rarely hyperplasia, cancer of parathyroid glands. The authors operated sucessfully a case of primary parathyroid adenoma by diagnosed by nuclear medical diagnostic work-up. The patient had anterior neck mass(soft, non tender nodule) on physical examination, multiple goiter on thyroid ultrasonogram and scan. The parathyroid lesion was difficult to find preoperatively.

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Alternatives on The Rehabilitation & Upgrading of Irrigation Facilitties by Agriculture Situation Change (농업여건 변화에 따른 수리시설 개보수 방향)

  • Lee, Young-Il;Kim, Hyeon-Soo;Jun, Taek-Ki
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 2005.10a
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    • pp.38-44
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    • 2005
  • Rehabilitation and upgrading of the irrigation facilities are usually for the reservoirs, pumping stations, and other facilities in the paddy fields. Changes in food consumption patterns have taken place in Korea and there are growing foreign demands that we open our agricultural products market. In accordance with this situation, farmers are turning increasingly to growing vegetables which provide a high income cash crop. It is necessary to irrigate by pressure through pipe lines in farming facilities and mass production farming. Flood damage occurs as a result of heavy rainfall. The design criteria should be followed to minimize the risk of the flood damage in rehabilitation and upgrading.

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