• Title/Summary/Keyword: Ambiguity area

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A Study on the enhancement of Effectiveness of the Pre Disaster Impact Assessment Review Deliberation System (사전재해영향성검토협의제도의 효율성 제고를 위한 연구)

  • Park, In-Chan;Cho, Won-Cheol;Seo, Jung-Pyo;Hong, Cheol
    • 한국방재학회:학술대회논문집
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    • 2008.02a
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    • pp.135-138
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    • 2008
  • As the procedure of the close examination of disaster impact at the initial stage of the beginning of development plans, the newly extablished Pre Disaster Impact Assessment Review Deliberation (PDIARD) system which have been introduced through the revision of the Natural Disaster Countermeasure Act-revised at August, 2005 is enforced for the purpose of the disaster prevention which caused during a development projects. From that time down to this day, the PDIARD system have been reviewed about 6,000 cases totally. However, the current the PDIARD system at the uppermost limit in the aspect of every Acts and operational problems is in need of sustaining supplementation at the present situation. To cope with this operational remedy related to the PDIARD system, this study deals in 3 major concerns. First, it is required to fix a criterion in detail because of a wide range of the subject plans of deliberation. Second, there is some ambiguity according to the area or length of the subjected administrative and development plans. So it should be excepted of the targeted plans which has few probability in disaster potential or vulnerability. Finally, the subjected plans need to be added as to the continuous urbanization and industrialization and the enactment or revision of the Acts related. This study focuses on the investigation and analysis to find out the improvement way about the main problem pending of the PDIARD system, consequently suggests a effective remedy and new categories, including future directions and detailed plans for operation.

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Case Study for Ship Ad-hoc Networks under a Maritime Channel Model in Coastline Areas

  • Su, Xin;Yu, HaiFeng;Chang, KyungHi;Kim, Seung-Geun;Lim, Yong-Kon
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.10
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    • pp.4002-4014
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    • 2015
  • ITU-R M.1842-1, as a well-known specification dedicated to maritime mobile applications, has standardized wireless transmission protocols according to the particular characteristics of a maritime communications scenario. A time division multiple access (TDMA) frame structure, along with modulation schemes to achieve a high data rate, has been described clearly in ITU-R M.1842-1. However, several specification items are still under "to be decided" status, which brings ambiguity to research works. In addition, the current version of ITU-R M.1842-1 is focused mainly on maritime transmissions in open-sea areas, where the cyclic prefix (CP) is set to zero and only 16-QAM is used in the multi-carrier (MC) system. System performance might be dramatically degraded in coastline areas due to the inter-symbol interference (ISI) caused by selective fading. This is because there is a higher probability that the signal will be reflected by obstacles in coastline areas. In this paper, we introduce the transmission resource block (TRB) dedicated to ITU-R M.1842-1 for a ship ad-hoc network (SANET), where the pilot pattern of TRB is based on the terrestrial trunked radio (TETRA). After that, we evaluated SANET performance under the maritime channel model in a coastline area. In order to avoid noise amplification and to overcome the ISI caused by selective fading, several strategies are suggested and compared in the channel estimation and equalization procedures, where the link-level simulation results finally validate our proposals.

Performance Analysis of Quad-pol SAR System for Wide-Swath Operation Mode (광역관측 운용 모드에 대한 Quad-pol SAR 시스템의 성능 분석)

  • Lim, Jung-Hwan;Yoon, Seong Sik;Lee, Jae-Wook;Lee, Taek-Kyung;Ryu, Sang-Burm;Lee, Hyeon-Cheol;Lee, Sang-Gyu
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.30 no.2
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    • pp.141-151
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    • 2019
  • In this study, we propose a performance analysis of a quadrature-polarimetric(quad-pol) synthetic aperture radar(SAR) system for wide-swath operation mode and compare it with a single-pol system based on the operation mode. To achieve a shorter revisit time for an SAR satellite, we must observe a wide area, and two SAR operation modes exist for this purpose, which are called ScanSAR and SweepSAR. In general, a quad-pol SAR system can obtain a greater variety of information about a target than a single-pol system. Because this system affects system performance parameters, analyzing these effects is required. Based on a performance analysis of the wide-swath quad-pol SAR system, the system parameters and appropriate operation mode can be selected to satisfy the performance requirements.

A Study on the Intensity and Energy Attenuation of the 13 December 1996 Yeongweol Earthquake, Korea (1996년 12월 13일 영월 지진의 진도 및 에너지감쇠에 관한 연구)

  • 조봉곤;김성균;김우한;김준경;박창업
    • Journal of the Earthquake Engineering Society of Korea
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    • v.1 no.1
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    • pp.69-77
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    • 1997
  • An intensity survey on the 13 December 1996 Yeogweol earthquake has mode for 262 locations throughout southern part of Korean peninsula, then we investigated attenuation properties in the south Korean region as well as intensities distribution. In this study, intensities are estimated to be from II to possibly VIII. The iso-seismal intensity map we obtained shows general pattern of intensity distribution in the south korean region quite clearly despite the inherent uncertainties included in the process of intensity estimation. In case of intensity larger than VI, considerable damages such as fracturing walls are frequently reported. One of the significant feature of this intensity map is, considering its magnitude 4.5 reported by KMA, the felt area is unusually large covering most of the Korean Peninsular except Cheju island. This result indicates either the magnitude is under estimated or the focal depth is much deeper than expected. Assuming indicates either the magnitude is under estimated or the focal depth is much deeper than expected. Assuming shallow earthquake whose focal depth is by iso-seismal contour lines for intensity IV to VII, respectively. To resolve this ambiguity, more reliable estimation of focal depth and magnitude by using telesesmic instrumental records should be made in the future.

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Comparison and Optimization of Flux Chamber Methods of Methane Emissions from Landfill Surface Area (매립지 표면의 메탄 발산량 실측을 위한 플럭스 챔버의 방법론적 비교와 최적화)

  • Jeong, Jin Hee;Kang, Su Ji;Lim, Jong Myoung;Lee, Jin-Hong
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.10
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    • pp.535-542
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    • 2016
  • As one of the most cost-effective methods for surface emission measurements, flux chamber method has been used worldwide. It can be classified into two types: SFC (with slope method) and DFC (with steady-state method). SFC (static flux chamber) type needs only simple equipment and is easy to handle. However, the value of flux might vary with SFC method, because it assumes that the change of concentration in chamber is linear with time. Although more specific equipments are required for DFC (dynamic flux chamber) method, it can lead to a constant result without any ambiguity. We made a self-designed DFC using a small and compact kit, which recorded good sample homogeneity (RSD < 5%) and recovery ( > 90%). Relative expanded measurement uncertainty of this improved DFC method was 7.37%, which mainly came from uncontrolled sweep air. The study shows that the improved DFC method can be used to collect highly reliable emission data from large landfill area.

Aggregation of Decision Inputs with Ordered Weighted Averaging Operators and Application to the Multiple Criteria Decision Making Problems (순위가중치평균법에 의한 의사전략 결합 및 다기준의사결정 문제로의 적용)

  • Oh, Se-Woong;Park, Jong-Min;Yang, Young-Hoon;Seo, Ki-Yoel;Lee, Cheol-Young;Suh, Sang-Hyun
    • Journal of Navigation and Port Research
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    • v.31 no.6
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    • pp.537-543
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    • 2007
  • It's an important part to calculate the weights between criterions and to aggregate the decision inputs in a MCDM(Multi criterion decision making) This paper presents a method for aggregation cf decision inputs and application to the MCDM. We incorporate the fuzzy set theory and the basic nature of subjectivity due to ambiguity to achieve a flexible decision approach suitable for uncertain and fuzzy environments. To obtain the scoring that corresponds to the best alternative or the ranking of the alternatives, we need to use a total order for the fuzzy numbers involved in the problem. In this article, we consider a definition of such a total order, which is based on two subjective aspects: the degree of optimism/pessimism reflected with the ordered weighted averaging(OWA) oprators. A numerical example, expecially location analysis for anchorage area, is given to illustrate the approach.

Characteristics of Middle School Students' Open-Inquiry Report and Their Perceptions of Conducting Inquiry (중학생의 자유 탐구 보고서에 나타난 특징과 탐구 수행에 대한 학생들의 인식)

  • Park, Mi-Hyun;Cha, Jeong-Ho;Kim, In-Whan
    • Journal of the Korean Chemical Society
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    • v.56 no.3
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    • pp.371-377
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    • 2012
  • In this study, open inquiry reports of 165 eighth graders in Daegu were analyzed in terms of content area, the types of inquiry hypothesis, and the types of inquiry variables. Before summer vacation, students learned about inquiry process and explored their own inquiry topic for two class hours. During summer vacation, students performed open inquiry including problem selection, designing and performing experiment, data collection, data analysis, and writing report. After the vacation, students submitted their reports, and answered to additional survey regarding the source of inquiry idea, the definition of hypothesis, and the most difficult step of inquiry process. As a result, chemistry was the most dominant content area of the reports and biology and life science were the next. 130 out of 165 reports included inquiry hypotheses, and most of them were predictive hypotheses. In many reports, dependent and independent variables could not be identified because of their ambiguity. However, inquiry variables described in experimental design, which were mostly categorical variables, were clearer than those described in inquiry subject and inquiry hypothesis. The most difficult step of inquiry process for students was to generate an idea for open inquiry.

DEM Generation over Coastal Area using ALOS PALSAR Data - Focus on Coherence and Height Ambiguity - (ALOS PALSAR 자료를 이용한 연안지역의 DEM 생성 - 긴밀도와 고도 민감도 분석을 중심으로 -)

  • Choi, Jung-Hyun;Lee, Chang-Wook;Won, Joong-Sun
    • Korean Journal of Remote Sensing
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    • v.23 no.6
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    • pp.559-566
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    • 2007
  • The generation of precise digital elevation model (DEM) is very important in coastal area where time series are especially required. Although a LIDAR system is useful in coastal regions, it is not yet popular in Korea mainly because of its high surveying cost and national security reasons. Recently, precise DEM has been made using radar interferometry and waterline methods. One of these methods, spaceborne imaging radar interferometry has been widely used to measure the topography and deformation of the Earth. We acquired ALOS PALSAR FBD mode (Fine Beam Dual) data for evaluating the quality of interferograms and their coherency. We attempted to construct DEM using ALOS PALSAR pairs - One pair is 2007/05/22 and 2007/08/22, another pair is 2007/08/22 and 2007/10/22 with respective perpendicular baseline of 820 m, 312m and respective height sensitivity of 75 m and 185m at southern of Ganghwa tidal flat, Siwha- and Hwaong-lake over west coastal of Korea peninsula. Ganghwa tidal flat has low coherence between 0.3 and 0.5 of 2007/05/22 and 2007/08/22 pair. However, Siwha-lake and Hwaong-lake areas have a higher coherence value (From 0.7 and 0.9) than Ganghwa tidal area. The reason of difference coherence value is tidal condition between tidal flat area (Ganghwa) and reclaimed zone (Siwha-lake and Hwaong-lake). Therefore, DEM was constructed by ALOS PALSAR pair over Siwha-lake and Hwaong-lake. If the temporal baseline is enough short to maintain the coherent phases and height sensitivity is enough small, we will be able to successfully construct a precise DEM over coastal area. From now on, more ALOS PALSAR data will be needed to construct precise DEM of West Coast of Korea peninsular.

Flexible Specialization: A New Paradigm for Modern Industrial Society ? (柔軟的 專門化(Flexible Specialization) : 현대 産業社會의 새로운 패러다임 ?)

  • Lee, Deog-An
    • Journal of the Korean Geographical Society
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    • v.28 no.2
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    • pp.148-162
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    • 1993
  • There is much speculation that modern capi-talist society is undergoing fundamental and qualitative chnge towards flexible specialization. The purpose of this study is to examine this hypothesis. This paper focusses on: the idea of flexible specialization; the significance of this transition; industrial district; and the implicati-ons of this new production system for Korean industrial space. Main arguments of this study are as follows: First, as all different groups of researchers apply the idea of flexible specialization according to their own specifications, the current debate on this topic is not much fruitful. Not surpri-singly, the concept of flexible specialization has overlapped with subocontracting. This intergration of subcontracting into flexible specialization systems, however, is inappropriate because the two concepts have different historical contexts. The other cause of this controversy is its inherent weekness, conceptual ambiguity. Thus, today's flexibility becomes tomorrow's rigidity. Secondly, transition towards flexible speciali-zation has only been partially achieved even in advanced capitalist countries. The application of dualistic explanatory framework, such as rigidity versus flexibiity, mass production versus small-lot multi-product production, and de-skilling versus re-skilling, has resulted in great exaggeration of the transformation, from Fordism to post-Fordism. There is no intermediary part between two places. Considering that the workers allocated to the Fordist mass production assembly line are not as large as one might imagine, the shift from mass to flexible production has only limited implications for the transformation of capitalist economy. Thirdly, 'industrial district' contorversy has contributed to highlighting the importance of small firms and areas as production space. The agglomeration of small firms in specific areas is common in Korea, but it is quite different from the industrial district based on flexible specialization. The Korean phenomenon stems from close interactions with its major parent firm rather than interactions between flexible, specialized, autonomous and technology-intensive smll firms. Most Korean subcontractors are still low-skilled, labour-intensive, and heavily dependent on their mojor parent firms. Thus, the assertion that the Seoul Metropolitan Area adopts flexible specialization has no base. Fourthly, the main concern of flexible speciali zation is small firms. However, the corporate organization that needs product diversification and technological specialization is oligopolistic large corporations typified by multinational corporations. It is because of this that most of these organizations are adoptiong Fordist mass production methods. The problem of product diversification will be resolved naturally if economic internationalization progresses further. What is more important for business success is the quality and price competitiveness of firms rather than product diversification. Lastly, in order to dispel further misunderst-anding on this issue, it is imparative that the conceptual ambiguity is resolved most urgently. This study recommends adoption of more speci-fied and direct terminology (such as, factory automation, computer design, out-sourcing, the exploitation of part-time labor, job redesign) rather than that of ideological ones (such as, Taylorism, Fordism, neo-Taylorism, neo-Fordism, post-fordism, flexible specialization, peripheral post-Fordism). As the debates on this topic just started, we still have long way to go until consensus is reached.

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Effect on the Burnout of Nursing Care Workers (요양보호사의 소진에 미치는 영향)

  • Kim, Young-Chun
    • The Journal of the Korea Contents Association
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    • v.20 no.11
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    • pp.590-602
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    • 2020
  • This study was conducted to understand the effects of job stress, empowerment, and organizational commitment of nursing care workers on burnout For this study, nursing care workers working at long-term care institutions in Gwangju and Jeonnam were conducted. As a result of the study, it was found that excessive role, role conflict, and role ambiguity perceived by nursing care workers had a positive effect on burnout. Individual competencies, job relationship competencies, and organizational environment competencies were found to negatively affect burnout. In addition, it was found that emotional and normative commitment negatively affected burnout, and continuous commitment had a positive effect. Overall, it was found that job stress, empowerment, and organizational commitment had an effect on burnout in order. Based on the results of these studies, it is necessary to establish a fair personnel management system, such as assigning roles appropriate to the nursing care worker's ability and aptitude, selecting, placing, and evaluating targets. It is necessary to create a systematic work environment such as training and provision of supervision. In addition, nursing care workers should relieve stress that occurs in the process of performing their duties, and provide an appropriate rest area for leisure to facilitate work.