• Title/Summary/Keyword: problem analysis

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THREE-SITE PHOTOMETRIC MONITORING OF THE δ SCT-TYPE PULSATING STAR V1162 ORIONIS : PERIOD CHANGE AND ITS IMPLICATIONS FOR PRE-MAIN SEQUENCE EVOLUTION

  • KIM, SEUNG-LEE;CHA, SANG-MOK;LIM, BEOMDU;LEE, JAE WOO;LEE, CHUNG-UK;LEE, YONGSEOK;KIM, DONG-JIN;LEE, DONG-JOO;KOO, JAE-RIM;HONG, KYEONGSOO;RYU, YOON-HYUN;PARK, BYEONG-GON
    • Journal of The Korean Astronomical Society
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    • v.49 no.5
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    • pp.199-208
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    • 2016
  • We present photometric results of the δ Sct star V1162 Ori, which is extensively monitored for a total of 49 nights from mid-December 2014 to early-March 2015. The observations are made with three KMTNet (Korea Microlensing Telescope Network) 1.6 m telescopes installed in Chile, South Africa, and Australia. Multiple frequency analysis is applied to the data and resulted in clear detection of seven frequencies without an alias problem: five known frequencies and two new ones with small amplitudes of 1.2-1.7 mmag. The amplitudes of all but one frequency are significantly different from previous results, confirming the existence of long-term amplitude changes. We examine the variations in pulsation timings of V1162 Ori for about 30 years by using the times of maximum light obtained from our data and collected from the literatures. The O − C (Observed minus Calculated) timing diagram shows a combination of a downward parabolic variation with a period decreasing rate of (1/P)dP/dt = −4.22 × 10−6 year−1 and a cyclic change with a period of about 2780 days. The most probable explanation for this cyclic variation is the light-travel-time effect caused by an unknown binary companion, which has a minimum mass of 0.69 M. V1162 Ori is the first δ Sct-type pulsating star of which the observed fast period decrease can be interpreted as an evolutionary effect of a pre-main sequence star, considering its membership of the Orion OB 1c association.

Classification and Profiling of Bus Stops in Gyeong-gi Province on the Basis of Trip Chain Variables (통행연계 변수를 중심으로 한 경기도 버스정류장 유형 구분)

  • Bin, Mi-Young;Jung, Eui-Seok;Lee, Won-Do;Joh, Chang-Hyeon
    • Journal of the Economic Geographical Society of Korea
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    • v.15 no.2
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    • pp.332-342
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    • 2012
  • The current research aims at classifying the bus stops as transfer center in order to establish the rational bus transfer systems. Existing research typically identifies characteristics of demands for bus stops and land use surrounding the bus stops and classifies and profiles the bus stops. A common problem with this type of research is that the results with cross-sectional characteristics of land use and bus stop usage do not capture the details of trip chain, the fundamental characteristics of the trips with transfer. This paper therefore examines bus stop classifications with such variables as transport mode chains, intermediate stop chains and timing chains. The analysis on the data collected on Monday 20 April 2009 for passengers of Gyeong-gi bus results in a clear classification among bus stops in terms of such trip chain variables. The research would provide useful information for the decision support of transfer stops location choice and infrastructure design.

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Analysis on the Temperature of 3D Multi-core Processors according to Vertical Placement of Core and L2 Cache (코어와 L2 캐쉬의 수직적 배치 관계에 따른 3차원 멀티코어 프로세서의 온도 분석)

  • Son, Dong-Oh;Ahn, Jin-Woo;Park, Jae-Hyung;Kim, Jong-Myon;Kim, Cheol-Hong
    • Journal of the Korea Society of Computer and Information
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    • v.16 no.6
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    • pp.1-10
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    • 2011
  • In designing multi-core processors, interconnection delay is one of the major constraints in performance improvement. To solve this problem, the 3-dimensional integration technology has been adopted in designing multi-core processors. The 3D multi-core architecture can reduce the physical wire length by stacking cores vertically, leading to reduced interconnection delay and reduced power consumption. However, the power density of 3D multi-core architecture is increased significantly compared to the traditional 2D multi-core architecture, resulting in the increased temperature of the processor. In this paper, the floorplan methods which change the forms of vertical placement of the core and the level-2 cache are analyzed to solve the thermal problems in 3D multi-core processors. According to the experimental results, it is an effective way to reduce the temperature in the processor that the core and the level-2 cache are stacked adjacently. Compared to the floorplan where cores are stacked adjacently to each other, the floorplan where the core is stacked adjacently to the level-2 cache can reduce the temperature by 22% in the case of 4-layers, and by 13% in the case of 2-layers.

Problems and Solutions for Multi-Cultural Family Support Act (다문화가족지원법제에 대한 문제점과 개선방안)

  • Kim, Jae-Nam
    • Journal of the Korea Society of Computer and Information
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    • v.20 no.6
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    • pp.117-126
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    • 2015
  • Multi-Cultural Family Support Act means that to lead a stable family life in Korea by improves the quality of life for members of multi-cultural families through the extensive support and ultimately it refers to a law designed to contribute to the integration between society and them. This Law was newly enacted as Law No. 8937 in March 21, 2008. And through the six times amendments it improve the part of the lack also now in February 18, 2015, some amendments are submitted by Jasmine Lee with 12 lawmakers. Now in 2015, the number of foreigners who living in Korea are beyond 150 million and it can see that has entered into a full-fledged multi-cultural society. And it can place a greater significance that had laid the foundation of the various support policies to lead a stable family life for members of multi-cultural families. However, the problem that much current law which associated with the Multi-cultural Family Support Act cannot accept the social changes has emerged. Thus, in this paper try to present a legislative plan that can respond appropriately to the real world through the analysis of it.

A Priority Analysis of Construction Strategies for Offshore Supply Base in Korea (국내 해양보급기지(Offshore Supply Base) 구축방안에 관한 우선순위 분석)

  • Jeong, Su-hyun;Kim, Yong-ho;Lee, Ji-won;Shin, Chang-hoon
    • Journal of Korea Port Economic Association
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    • v.32 no.4
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    • pp.57-71
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    • 2016
  • The development of ocean industries is an existing and important problem for South Korea, which is mostly surrounded by sea and has a long coastline along three seas. It is necessary for researchers to make efforts to enhance its cost and time competitiveness, because many ocean-based activities have been carried out in harsh physical conditions when compared with land-based ones. One of these efforts to improve efficiency is to operate an Offshore Supply Base (OSB), which is a basic infrastructure required to develop ocean industries effectively. For this reason, the construction and operation of OSBs have become an issue in Korea. The relevant research is limited. Nevertheless, there are a few reports published by Korean research institution. They focus on promoting ocean industries and only mention the necessity of OSB as a promotion tool for the industries. This study on the other hand, addresses various issues on the construction of OSBs in Korea and suggests implications for them. To examine the conditions on the construction of OSBs in Korea, we conduct case studies of Houston and Singapore, the representative regions where a massive OSB has been constructed and operated. In addition, we use Analytic Hierarchy Process (AHP) to evaluate the relative priorities of the services provided by OSBs if constructed in Korea.

ANALYSIS OF THE TRANSPORTATION LOGISTICS FOR SPENT NUCLEAR FUEL IN KOREA

  • Lee, Hyo-Jik;Ko, Won-Il;Seo, Ki-Seok
    • Nuclear Engineering and Technology
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    • v.42 no.5
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    • pp.582-589
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    • 2010
  • As a part of the back-end fuel cycle, transportation of spent nuclear fuel (SNF) from nuclear power plants (NPPs) to a fuel storage facility is very important in establishing a nuclear fuel cycle. In Korea, the accumulated amount of SNF in the NPP pools is troublesome since the temporary storage facilities at these NPP pools are expected to be full of SNF within ten years. Therefore, Korea cannot help but plan for the construction of an interim storage facility to solve this problem in the near future. Especially, a decision on several factors, such as where the interim storage facility should be located, how many casks a transport ship can carry at a time and how many casks are initially required, affect the configuration of the transportation system. In order to analyze the various possible candidate scenarios, we assumed four cases for the interim storage facility location, three cases for the load capacity that a transport ship can carry and two cases for the total amount of casks used for transportation. First, this study considered the currently accumulated amount of SNF in Korea, and the amount of SNF generated from NPPs until all NPPs are shut down. Then, how much SNF per year must be transported from the NPPs to an interim storage facility was calculated during an assumed transportation period. Second, 24 candidate transportation scenarios were constructed by a combination of the decision factors. To construct viable yearly transportation schedules for the selected 24 scenarios, we created a spreadsheet program named TranScenario, which was developed by using MS EXCEL. TranScenario can help schedulers input shipping routes and allocate transportation casks. Also, TranScenario provides information on the cask distribution in the NPPs and in the interim storage facility automatically, by displaying it in real time according to the shipping routes, cask types and cask numbers that the user generates. Once a yearly transportation schedule is established, TranScenario provides some statistical information, such as the voyage time, the availability of the interim storage facility, the number of transported casks sent from the NPPs, and the number of transported casks received at the interim storage facility. By using this information, users can verify and validate a yearly transportation schedule. In this way, the 24 candidate scenarios could be constructed easily. Finally, these 24 scenarios were compared in terms of their operation cost.

CLINICOSTATISTICAL ANALYSIS OF SURGICAL FINDINGS IN CHRONIC OTITIS MEDIA (만성 중이염의 수술시 소견에 대한 임상통계적 관찰)

  • 최덕주;전병훈;민원식;함태영
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1987.05a
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    • pp.6-6
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    • 1987
  • 만성중이염은 현재 그 빈도가 줄어드는 추세에 있으나 아직도 이과 영역에서 큰 비중을 차지하는 질환이다. 또한 청력개선, 정상구조의 보존, 병변 제거의 목적을 위하여 대부분 수술적 요법이 필요하게 된다. 이에 저자들은 본 병원에서 시행한 만성 중이염 451예, 남자 238예, 여자 213예. 진주종성 중이염 170예, 비진주종성 중이염 273예에 대한 수술시 소견에 대한 임상 통계적 관찰을 한 바, 다음과 같은 결과를 얻었다. 1) 관찰대상을 술식별로 분류하면 진주종성 중이염과 비진주종성 중이염의 비가 $\circled1$ Myningoplasty ; 19.1% : 0%, $\circled2$ Tympanoplasty without mastoidectomy ; 34.5% : 14.4%, $\circled3$ Tympanoplasty with mastoidectomy ; 3.0% :12.1% 이었다. 2) 고막천공부위는, 진주종성 중이염과 비진주종성 중이염의 비가 변연부천공이 10.1% : 5.5%, 상고실천공이 38.8% : 1.4%, 중심부천증이 12.9% : 47.3%, 전천공이 32.5% : 39.6%, 고막유착이 5.6% : 6.2% 을 보였다. 3) 이소골의 상태는 진주종성중이염과 비진주종성 중이염의 비가, 모든 이소골의 손실은 26.6% : 4.3%, 모든 이소골이 정상에 가까운 예는 16.6% : 69.3%, 가장 병변이 심했던 침골 이상은 76.9% : 24.8% 를 보였다. 4) 중이강 점막소견은 진주종성 중이염과 비진주종성 중이염의 비가, 정상에 가까운 예가 16.7% : 47.0%, 병적 소견을 보인 예가 83.3% : 53.0% 이었다. 5) 진주종성 중이염과, 비진주종성 중이염에서의 안면신경관노출은 2.2% : 0.3%, 뇌막노출은 9.5% : 2.9%, 횡정맥동노출은 5.0% : 1.1%, 미로누공은 1.7% : 0% 이었다.lant, engineering service business can be said "The Software of Total Industry." Engineering service is what is called a higher business which offers specialized engineering know-how and experience. Engineering service compaines offer Its specialized knowledge and experience to government, industry and commerce. Whether the task is to modernize plant equipment, to design a building or to manage construction, an engineering company will develop and implement the most appropriate and cost effective solution. Clients use the engineering service of firm knowing that the engineer′s professional judgement is not influenced or biased by other commercial affiliations. While benefiting from the diverse experience that professional engineers can apply to a specific problem, government and industry also reduce the need for permanent in-house engineering staff. Engineering firms may be specialized or multi-disciplinary.도말표본에서와 같이 제 14 일 이전에는 호중구가, 그 이후에는 단핵구가 주종을 이루었다.>18.9dB

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Monitoring and risk assessment of pesticide in school foodservice products in seoul, Korea (서울지역 학교급식 식재료의 잔류농약 위해성 평가)

  • Seo, Young-Ho;Moon, Kwang-Deog
    • Food Science and Preservation
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    • v.21 no.1
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    • pp.69-74
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    • 2014
  • We tested for residual pesticide levels in school foodservice agricultural products in Seoul, Korea from 2010 to 2012. A total of 316 samples of 23 different types of agricultural products were analyzed via gas chromatography-nitrogen phosphate detector (GC-NPD), an electron capture detector (GC-${\mu}ECD$), a mass spectrometry detector (GC-MSD), and a high performance liquid chromatography-ultraviolet detector (HPLC-UV). We used multi-analysis methods to analyze 185 different pesticide types. Among the selected agricultural products, residual pesticides were detected in 26 samples (8.2%), of which 6 samples (1.9%) exceeded the Korea Maximum Residue limits (MRLs). We detected pesticide residue in more than 65% of the Chwinamul, while 6 among 9 analyzed samples contained pesticide residue, and 1 sample exceeded the Korea MRLs. Among the 185 kinds of pesticides that we have tested, 18 were detected, while 7 of them were detected more than twice. Data obtained were then used for estimating the potential health risks associated with the exposures to these pesticides. The most critical commodity is carbofuran in the perilla leaves, which has contributed 3.8% to the hazard index (HI). These results showed that the detected pesticides could not be considered as a serious public health problem. Nevertheless, constant supervision is recommended.

Relationship Between the Technology Innovation Performance of IT Venture Business and CEO Characteristics (기술혁신 성과와 경영자 특성에 관한 연구: IT벤처기업을 중심으로)

  • Park, Jae-Min;Kim, Hyo-Young
    • Journal of Digital Convergence
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    • v.9 no.6
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    • pp.173-186
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    • 2011
  • In this study, the influence of the CEOs' characteristics on the technology innovation performances of IT venture companies was analyzed. The relation between business performance and the characteristics of CEOs has been dealt with in earlier studies, but most paid attention to financial perspective, and few of these focused on the influence of managers on technology innovation. On the other hand, most of the studies related to the role of managers in technology innovation mainly focused on R&D investment and research infrastructure but did not delve on the characteristics of them in an in-depth way. In this study, the characteristics of CEOs and their technology innovation performances were empirically analyzed based on the results of a recently conducted survey on the IT venture companies. In the analytical aspect, a negative binominal model was applied to solve the over-dispersion problem that often appears in the count variable analysis. As a result, it was found that major, work type, and work experience, among managers' characteristics, have significant influences on managers' technology innovation performances, along with the company's innovation capacity, technological competitiveness, market competition, and support from the government.

Analysis on the installation criteria and ventilation effect for round roof windows in single-span plastic greenhouses (단동 플라스틱 온실의 천창 환기효과와 설치기준 분석)

  • Nam, Sang-Woon;Kim, Young-Shik;Ko, Gi-Hyuk;Sung, In-Mo
    • Korean Journal of Agricultural Science
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    • v.39 no.2
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    • pp.271-277
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    • 2012
  • Dimensions, operation conditions and improvement items for round roof windows were investigated in arch shape single-span plastic greenhouse with roof vents, and natural ventilation performance was analyzed based on the ventilation theory. Diameter of round roof windows was mostly 60 cm, and chimney height projected on roof was average 30 cm. Installation space was mostly 5 to 6 m but farmhouse of 10 m and over was 16.7% also. A round roof window which has 60 cm diameter was installed to 6 m space generally and 80 cm diameter was installed to 10 m space, but correct standards did not exist. There were a lot of opinions that ventilation effect of round roof windows is fairly good and user satisfaction is generally excellent. It is problem that there is few effects in summer and that vinyl around each vent tears well and rainwater leaks, and improvement hope item required development of automatic control system. In the wind speed of 0.3 m/s, it was estimated that natural ventilation rates were 0.69, 0.55, 0.50 and 0.48 volumes per minute in case of 2, 4, 6 and 8 m installation space for round roof windows, respectively. It was analyzed that the ratio of ventilation due to buoyancy out of total ventilation were 65.2, 41.9, 29.9 and 22.8% in case of 2, 4, 6 and 8m installation space, respectively. By the round roof windows installed at space of 6 m, ventilation rate was estimated to 0.5 volumes per minute, and we can expect the increase in ventilation rate of 30%. In order to meet the recommended ventilation rate for summer season, we have to install the round roof windows at space of 1 to 2 m. However, it is difficult to apply those installation space because of falling productivity due to lower light transmittance as well as rising costs. It is estimated that the installation space of 6m is appropriate for spring or fall season. Therefore it is necessary to encourage installing the roof windows in single-span plastic greenhouses.