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Performance Prediction of Geothermal Heat Pump(GHP) System with Energy Piles Using Simulation Approach (시뮬레이션을 통한 에너지파일 적용 지열 히트펌프 시스템의 성능 예측)

  • Sohn, Byong-Hu;Choi, Jong-Min
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.24 no.2
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    • pp.155-163
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    • 2012
  • The aim of this study is to evaluate the performance of the GHP system with 150 energy piles for a commercial building. In order to demonstrate the feasibility of a sustainable performance of the system, simulations were conducted over 1-year and 20-year periods, respectively. The 1-year simulation results showed that the maximum and minimum temperatures of brine returning from the energy piles were $23.80^{\circ}C$ and $7.90^{\circ}C$, which were in a range of design target temperatures. In addition, after 20 years' operation, these returning temperatures decreased slowly to $23.05^{\circ}C$ and $6.98^{\circ}C$, and finally reached to stable state. The results also showed that the energy piles injected heat of 65.6 MWh to the ground and extracted heat of 96.0 MWh from the ground, respectively. Also, it is expected this GHP system with energy piles can operate with average SPF of more than 4.15 for long term.

The Water Resource Management Framework in New Zealand: A Case Study of Moving towards a Less Adversarial Approach

  • Davie, Tim
    • Proceedings of the Korea Water Resources Association Conference
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    • 2010.05a
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    • pp.82-90
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    • 2010
  • New Zealand appears to be a water rich country; however there are considerable water allocation issues. Mostly these revolve around balancing environmental concerns with economic development. The largest economic sector is agriculture which currently utilizes around 80% of the allocated water and has considerable potential to increase in size. The resource management framework that New Zealand has developed over the past twenty years revolves around local decision-making and sustainable management principles. As the demands for water have grown there has been growing concern that this framework is inadequate to deal with the issues of declining water quantity and quality through agricultural intensification. In Canterbury, the region with the highest water allocation and demand, a new approach is being trialed. The Canterbury Water Management Strategy (CWMS) recognizes the need for: ecological restoration for past damage; infrastructure development for increased irrigation; and the need to link infrastructure with more efficient use of water by both existing and new water users. These three elements are recognized as having equal value. The CWMS builds on the local decision-making concept but is deliberately aimed at consensus building in order to remove expensive and adversarial resource management hearings. It is practical enough to recognize that economic development is needed but that it need not proceed in conflict with the environment, but rather can be a means towards environmental improvement.

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A Study on the Influence of Al Alloy Sacrificial Anode Efficiency due to Marine Environmental Variation (해양환경 변화가 알루미늄합금 희생양극의 효율에 미치는 영향에 관한 연구)

  • 김도형
    • Journal of Ocean Engineering and Technology
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    • v.14 no.2
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    • pp.106-111
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    • 2000
  • Recently it was reported that the life of Al Sacrifical anode is being used in port piers has been significantly shortened compared with the original design life (e.g. average life shortened from 20 years to 13-15 year) Those factors involving these problems mentioned above were seemed to be a quality of anode material and diverse environmental factors such as pH flow rate temperature Dissolved oxygen Chemical oxygen demand and resistivity etcm In this study flow rate and contamination degree(pH) of sea water affecting to sacrificial anode life hve been investigated in terms of electrochemical characteristics of Al alloy sacrificial anode It was known that the lifetime of Al alloy anode was shortened not only by increasing of self-corrosion quantity by varying flow rate of sea water but also by increasing corrosion current density due to the potential difference increment between Al anode and steel structure cathode by varying contamination degree of sea water. Especially when anode current density is from 1mA/cm2 to 3mA/cm2 and flow rate of sea water is under 2m/s anode current efficiency is 90% above However flow rate is over 2m/s anode current efficiency fell down sharply due to erosion corrosion as well as galvanic corrosion.

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Non-Governmental Organization (NGO) Libraries for The Visually Impaired in Nigeria: Alternative Format Use and Perception of Information Services

  • Adetoro, 'Niran
    • Journal of Information Science Theory and Practice
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    • v.3 no.1
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    • pp.40-49
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    • 2015
  • Nigeria's non-government organization (NGO) libraries for the visually impaired has over the years been at the forefront of information services provision to persons with visual impairment. This study adopted a survey research design to investigate use of alternative formats and perceptions of information services to the visually impaired, focusing on two purposively chosen NGO libraries for the visually impaired in Nigeria. Using a complete enumeration approach, data were gathered from 180 users of the libraries through the use of a structured questionnaire with a reliability score (${\alpha}=0.74$). Data from 112 (62.2%) of the 180 administered copies of a questionnaire that were retrieved were analysed. The study found that Braille materials had a high level of utilization ($\bar{x}=4.46$) and were the most frequently utilized (90.9%). Perception of information services by the visually impaired was positive while use of alternative formats was significantly and positively related to users' perception of information services (r = .041; p < 0.05). The study recommends improved transcription and investment in alternative formats and in e-resources. It also recommends collaborations to widen access as well as constant evaluation of services.

Study on Weaning Practice of Infants in Chunchon Area, Kangwon-Do (강원도 춘천지역 유아의 이유실태에 관한 조사연구)

  • 이정수
    • Journal of Nutrition and Health
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    • v.27 no.3
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    • pp.272-280
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    • 1994
  • The weaning practice of infants from 5 to 12 months of age in the area of Chunchon, Kangwon-do was studied. Subjects were divided into 2 groups depending on residential area, monthly family income and mother's educational level. Parents of group 1 (n=90) received higher education and more monthly family income than those of group 2(n=32). The family income was significantly higher in group 1 than in group 2. Mother's educational level has been markedly improved over 10 years, which affected the feeding methods before weaning in both groups(P<0.05). Group 1 appeared to be bottle-fed. Bottle-and mixed-feeding were mainly due to lack of breast milk. 95.6% of group 1 and 71.9% of group 2 started weaning before the age of 6 months and only 16.4% were completely finished regardless of the groups. Commercially prepared foods were used more than home-made for first given-supplementary food. 82.2% of group 1 received fruits and 84.4% of group 2 cookies/crackers as their main supplementary foods. As the motivation of onset of weaning, 'for baby's health and nutritional status' was the most common. These results demonstrate that there are distinct differences between these 2 groups in 1) the feeding methods prior to weaning, 2) time of onset of weaning, and 3) main supplementary foods, influenced by mother's educational level, economic purchasing power, or subjects birth order.

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Acute Organophosphorus Pesticide Poisoning (급성 유기인계 농약 중독)

  • Lee, Mi-Jin;Park, Joon-Seok;Hong, Tai-Yong;Park, Sung-Soo;You, Yeon-Ho
    • Journal of The Korean Society of Clinical Toxicology
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    • v.6 no.2
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    • pp.83-90
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    • 2008
  • Organophosphate (OP) pesticides are the most common source of human toxicity globally, causing high mortality and morbidity despite the availability of atropine as a specific antidote and oximes to reactivate acetylcholinesterase. The primary toxicity mechanism is inhibition of acetylcholinesterase (AchE), resulting in accumulation of the neurotransmitter, acetylcholine, and abnormal stimulation of acetylcholine receptors. Thus, the symptoms (muscarinic, nicotinic, and central nervous system) result from cholinergic overactivity because of AchE inhibition. OP can also cause rhabdomyolysis, pancreatitis, parotitis, and hepatitis. OP therapy includes decontamination, supportive therapy, and the use of specific antidotes such as atropine and oximes. However, there has been a paucity of controlled trials in humans. Here we evaluated the literature for advances in therapeutic strategies for acute OP poisoning over the last 10 years.

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The effect of chewing difficulty on depression in Korean adults over aged 40 years : The 7th Korean National Health and Nutrition Examination survey (2016~2018) (제7기(2016~2018) 국민건강영양조사를 이용한 40세 이상 한국 성인의 저작불편감이 우울에 미치는 영향)

  • Nam, Ji-Ae;Lee, Jung-Hwa
    • Journal of Korean society of Dental Hygiene
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    • v.21 no.5
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    • pp.601-610
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    • 2021
  • Objectives: The purpose of this study was to analyze the effect of chewing difficulty on depression in Korean adults to provide basic data on improving the quality of life related to oral health of Korean adults. Methods: The raw data of the analysis were obtained from the dataset of the seven Korea National Health and Nutrition Examination Survey conducted between 2016 and 2018. The subjects included 9,535 people who underwent oral examination and answered questions. The collected data were analyzed using the SPSS (ver 21.0) program using composite samples, and the mean crossover analysis and logistic return analysis were performed. Results: An analysis of the effects of chewing difficulty on depression in Korean adults showed that those with chewing difficulty had a 2.24 fold higher risk of depression (95% CI: 1.73-2.90) and a statistically significant difference (p<0.05). Conclusions: The association between the chewing difficulty on depression could be confirmed, and measures improve of the oral health and preventing depression should be prepared.

The Impact of Government Innovation Subsidies on the Survival of SMEs in Korea

  • Kim, Sangsin
    • STI Policy Review
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    • v.9 no.1
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    • pp.55-76
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    • 2018
  • This study analyzed the effect of the government R&D subsidy program on long-term firm survival. In order to estimate the average treatment effect for the treated group, we used the survival analysis and matching method by constituting a comprehensive dataset of more than 90,000 observations. The analysis results show that the government R&D subsidy has a negative impact on long-term firm survival. In particular, not only the subsidy does not have a statistically significant effect on firm survival in the relatively short-term, the survival probability of the subsidized firms is statistically significantly lower than the non-subsidized firms after six years. These results can be seen as weakening the justification of government R&D support. There may be problems in the subsidy policy itself and the process of selection of subsidy awardees; however, the more fundamental problem is that the subsidy policy is concluded as the one-time event. Admittedly, it would be difficult for the government to precisely manage the subsidized projects over a long term period. However, in the case of a project in which short-term performance is detected, it would be necessary to provide a step-by-step support to strengthen the firm's competitiveness through further support and continuous development of performance. Of course, mid- and long-term evaluations of subsidy support policy should be performed in parallel with such phased support.

A Study about Expanding into International Markets through International Apparel Fairs -Emphasis on the Las Vegas Magic Show- (의류 수주전시회를 통한 해외 시장 진출 방안에 관한 연구 -라스베이거스 매직쇼(Magic Show)를 중심으로-)

  • Lim, Jisook
    • Journal of Fashion Business
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    • v.25 no.1
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    • pp.65-79
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    • 2021
  • Apparel fairs are business platforms specializing in selling fashion products. As the largest apparel fair in the United States and with the highest number of animated buyers in the entire world, the Las Vegas Magic Show utilizes this distribution platform to the greatest extent by sustaining over 90,000 buyers annually. In accordance, the exhibiting companies also participate in commercial functions by striving to promote brand awareness to consumers as they carefully plan to increase actual sales and secure new customers. Domestically, numerous organizations such as the Trade Promotion Administration, the Korean Apparel Association, and KOTRA(Korea Trade-Investment Promotion Agency) present similar international apparel fairs to strongly encourage domestic companies to exhibit at international apparel fairs. However, many companies fail to succeed in achieving actual results, which frequently causes them to attend the shows for the short term only. This may occur due to the lack of research on apparel order-writing exhibitions by academia and proactive workers. This research study was based on the careful observation and analysis of the three most recent years of Magic exhibitor attendees' operations and changes to accomplish the final objective of presenting a basic guideline to attend an international apparel exhibition.

Regular pattern design using tartan proportions and grid manipulations

  • Wang, Chaoran;Hann, Michael A.
    • The Research Journal of the Costume Culture
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    • v.29 no.6
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    • pp.932-948
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    • 2021
  • Tartan, the woven, checked, and wool textile considered by many to be originally from Scotland, has in fact been in use in a range of forms across numerous cultures and during various historical periods. The characteristic checked feature is due to the assembly of different coloured threads in both warp and weft directions which intersect at 90 degrees in a combination known as a sett. For well over one hundred years, different setts and thus different colour combinations have been associated closely with different geographical regions within Scotland, as well as different clans or families. Tartan-type textiles have reached popularity at various times and those have often been a predicted fashion trend suggested, for example, by contributors to fashion gatherings such as Premier Vision in Paris. Often proposed designs are best considered based on tartan combinations rather than simple reproductions. Promotional terms such as "patched checks" or "textured checks" have been common, and often these have been derived from tartan-type constructions. This paper explores novel pattern design methods by identifying the underlying grid structures and proportions exhibited by various well-known tartan setts. The possibility of pattern development from tartan grids and their manipulations is thus the focus of attention. An insight into the methodology associated with the production of original pattern designs is thus provided.