• Title/Summary/Keyword: Worst case

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Comparison of Retention of Calcium Carbonate and Mechanical and Optical Properties of Sheets in Various Retention System (여러 가지 보류시스템에서 탄산칼슘의 보류와 종이의 기계적·광학적 특성의 비교)

  • Paik, Ki-Hyon;Ahn, Byoung-Jun;Shon, Sang-Don
    • Applied Chemistry for Engineering
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    • v.7 no.2
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    • pp.315-320
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    • 1996
  • In this paper, we investigated the retention amounts(ash contents) according to the addition amounts of retention aid and calcium carbonate and compared the mechanical and optical properties of sheets under the same ash content. As the addition amounts of retention aid increase, the retention of calcium carbonate, that is, ash contents of sheets increase in all retention system. In this case, the sheets included ash content as already expected is produced by adjusting the addition amounts of retention aid and calcium carbonate. Tensile index, burst index, tear index, internal bonding strength of sheets straightly decrease as the ash content of sheets increases. Especially, in the same ash content, all sorts of strength are high in compozil system, low in dual polymer system. Opacity increases along with according to the increase of ash content, and is high in hydrocol system, the worst in dual polymer system. In equal opacity, the strength of paper decreases compozil, hydrocol, and dual polymer system in order. But to judge she superiority or inferiority of retention aids, it should consider the various factors such as the optimum production and process conditions besides the retention amounts of filler and the sheet strength.

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A Study on Strategies for Enhancing Transparency of Domestic Construction Industry through Foreign Cases (해외사례를 통한 국내 건설산업의 투명성 제고에 관한 연구)

  • Jang, Hyeon Seok;Park, Hyung Keun;Lee, Young Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.3D
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    • pp.231-237
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    • 2012
  • The interrelation of integrity degree and country competitive power was known as high. But, according to the CPI announcement of Transparency International, the domestic Corruption Perceptions Index ranked 5 points, as being corrupt. It was investigated that the corruption level of Korea was getting worse most in the construction sector. In this way, it is emergent and inevitable to improve the transparency in the construction industry, accounting for 25-54% of the total corruption cases in our society. Transparency International has opened to the public the source data, utilized in the CPI measures in 2010. In the case of Korea, the 9 data of 6 organizations were utilized. According to the PERC, the corruption level of the private sector in Korea has been estimated as the worst among the 16 countries. In this context, this paper analyses the corruption level of Korea by utilizing the source data of the Transparency International CPI. And it aims to comprehend structural problems in the construction industry and to suggest implicative countermeasures through out the anti-corruption activities in the world. It propose finally an improvement of the structural causes in the construction industry, a promotion of effective punishment against corrupt practices, a reinforcement of the transparency management in the construction sector, etc.

A Study on a Coping Method of the Family Caregivers of Demented Patients (치매노인 가족부양자의 대처방법에 관한 연구)

  • You, Kwang-Soo
    • Research in Community and Public Health Nursing
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    • v.13 no.4
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    • pp.648-667
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    • 2002
  • This was a descriptive study designed to identify the level of coping method and its influencing factors on the family caregivers of demented patients, and resolve the family caregivers' level of stress. The data were collected from September 10 to October 10, 2001. Subjects for this study were recruited from four clinics, which were chosen from 15 clinics located in Chunbuk-Do as the study sites because of their cooperation for the study. They were similar in terms of size, the characteristics of the local community. and the population and registration status of the demented patients. The instruments used for the study were as follows: 1. Problematic behaviors of demented patients are measured by the Memory and Behavior Problem Checklist (Zarit, 1980), and the Linguistic Communication Symptoms Questionnaire (Bayles and Tomoeda, 1991) 2. The ability to carry out daily activities was measured using the Barthel Index (1965) and Katz Index (1963), which as well-known ADL assessment methods. 3. Burden was measured using Cost of Care Index by the Kosberg and Cairl (1986). 4. Coping strategy was measured Bell's 18 methods (1977). The data were analyzed using SPSS/PC. The study results were as follows: 1. The total stress score was 2.90 out of a maximum score of 5. The highest score reported was 3.09 on the dimension of restriction of individual and social activities, and the lowest region reported was 2.58 on the dimension of mental and physical health. 2. The total score of the coping method was 2.65 out of a maximum score of 5. The highest score reported was 4.01 on the dimension of thinking that includes an ideation such that it is better than any possible worst case, and the lowest score reported was 1.45 on the dimension of the self-image as a scapegoat. 3. There were significant differences in coping method among the subjects by age (F=2.752 p=0.04), caregiver (F=4.33 p=0.003), care-giving period (F=2.68 p=0.049), and dementia stage (F=2.87 p=0.034). 4. There were highly negative correlations ($\gamma$=-0.301 p=0.000) between problematic behaviors of demented patients and the coping method of their family caregivers. The highest correlation coefficient ($\gamma$=-0.339 p=0.000) was found between aggressive behaviors of the demented patients and the coping method of their family caregivers. 5. There was a low negative correlation ($\gamma$=-0.201 p=0.019) between the ADL of the demented patients and the coping method of their family caregivers. 6. There were highly negative correlations ($\gamma$=-0.213 p=0.005) between stress and the coping method of the family caregivers. The highest correlation was found between financial burden ($\gamma$=-.327 P=.000) and the coping method of the family caregivers. There was no significant correlation among unpleasant aspects of the demented patients, willingness to the demented patients, and the coping method of the family caregivers.

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Accommodation of Trade Measures for Environment Purposes on the WTO Rules (환경조치의 WTO체제 수용에 관한 연구)

  • Chae, Dae-Seok;Kim, Mie-Jung
    • International Commerce and Information Review
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    • v.13 no.3
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    • pp.433-457
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    • 2011
  • This study attempts to make a constructive contribution to the debate on which WTO rules accommodate trade measures for environmental purposes. Does trade undermine the regulatory efforts of governments. However, the theoretical dimensions are partly addressed on the several key questions. For instances, is economic integration through trade and investment a threat to the environment? to control pollution and resource degradation? Will economic grow driven by trade help us to move towards a sustainable use of the world's environmental resources? The growing world economy has been accompanied by environmental degradation including deforestation, losses in bio-diversity, global warming, air pollution, depletion of the ozone layer, overfishing and so on. The sheer number of us obviously put pressure on natural resources and ecological systems, and this pressure will counting to rise as we grow towards 10 billion in the next century. What is more, there is no indication that consumption per capita is slowing. The perceived costs of acting alone in terms of lost investments and jobs often take the stream out of regulatory initiatives. In the worst case scenario environmental community is fearful that international trade will magnify the effects of poor environmental polices in the world Generally, economic growth drive by trade may speed up the process of environmental degradation unless sufficient environmental safeguards are put in place. Under these circumstances, this paper attempts to make a constructive contribution to the study on which WTO rules accommodate trade measures for environmental purposes.

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Design and Implementation of Crash Recovery Technique with Bounded Execution Time for NAND Flash File System (낸드 플래시 파일 시스템을 위한 결함 복구 시간 제한 기법의 설계 및 구현)

  • Kang, Seung-Yup;Park, Hyun-Chan;Kim, Ki-Man;Yoo, Chuck
    • Journal of KIISE:Computer Systems and Theory
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    • v.37 no.6
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    • pp.330-338
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    • 2010
  • Flash storage devices are very popularly used in portable devices such as cell phones, PDAs and MP3 players. As technology is improved, users want much bigger and faster storage system. Paradoxically, people have to wait more and more time proportionally to the capacity of their storage devices when these are trying to be recovered after file system crash. It is serious problem because booting time of devices is dominated by crash recovery of flash file system. In this paper, we design a crash recovery mechanism, named 'Working Area(WA hereafter)' technique, which has bounded crash recovery execution time. With WA technique, write operations to flash memory are only performed in WA. Therefore, by simply scanning the latest WA. We can recover a file system crash because every change for flash memory is occured only in latest WA. We implement the WA technique based on YAFFS2 and evaluate by comparing with traditional techniques. As a result, WA technique shows that its crash recovery execution time is 25 times faster than Log-based Method when we use 1 gig a bytes NAND flash memory in worst case. This gap will be futher and futher as storage capacity grows.

A High-speed Packet Filtering System Architecture in Signature-based Network Intrusion Prevention (시그내쳐 기반의 네트워크 침입 방지에서 고속의 패킷 필터링을 위한 시스템 구조)

  • Kim, Dae-Young;Kim, Sun-Il;Lee, Jun-Yong
    • Journal of KIISE:Computer Systems and Theory
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    • v.34 no.2
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    • pp.73-83
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    • 2007
  • In network intrusion prevention, attack packets are detected and filtered out based on their attack signatures. Pattern matching is extensively used to find attack signatures and the most time-consuming execution part of Network Intrusion Prevention Systems(NIPS). Pattern matching is usually accelerated by hardware and should be performed at wire speed in NIPS. However, that alone is not good enough. First, pattern matching hardware should be able to generate sufficient pattern match information including the pattern index number and the location of the match found at wire speed. Second, it should support pattern grouping to reduce unnecessary pattern matches. Third, it should always have a constant worst-case performance even if the number of patterns is increased. Finally it should be able to update patterns in a few minutes or seconds without stopping its operations, We propose a system architecture to meet the above requirement. The system architecture can process multiple pattern characters in parallel and employs a pipeline architecture to achieve high speed. Using Xilinx FPGA simulation, we show that the new system stales well to achieve a high speed oner 10Gbps and satisfies all of the above requirements.

A Study on Systematic Risk Assessment Method for LNG Storage Facilities (LNG 저장설비에 대한 체계적인 위험성평가 방법에 관한 연구)

  • Kang, Mee-Jin;Lee, Young-Soon;Lee, Seung-Rim
    • Journal of the Korean Institute of Gas
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    • v.13 no.1
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    • pp.14-20
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    • 2009
  • As the consumption of LNG has increased, the capacity and number of LNG facilities are getting bigger and bigger. Such circumstances supports the need for a dedicated risk analysis model to help review and check major issues of the safer construction and operation of LNG storage facilities systematically. Therefore this study suggests an appropriate risk analysis model that enables us to evaluate hazards of LNG storage facilities more easily and systematically, and then to use its result in siting, design and construction stages of the facilities. ill order to develop the model, lots of existing studies and domestic and foreign codes and standards were fully reviewed and a series of case studies also were carried out. The suggested model consists of 4-stage evaluations: in selecting a site, in determining a layout, in designing and constructing the facilities, and in operating them. This model also suggests the weather condition necessary for estimating the consequence of accident-scenarios, and the easy, systematic approach to the analysis of their probability. We expect that the model may help secure LNG storage facilities' inherent safety in determining their site and layout.

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Perception and Production of English Grapheme <a> by Korean Students (한국 학생들의 영어 철자 <a> 인지와 발화)

Ligament Injuries of Knee in the Recreational Skiers (스키에 의한 슬관절 인대 손상)

  • Lee Dong Chul;Ko Jin Hyeok;Kim Dong Han
    • Journal of Korean Orthopaedic Sports Medicine
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    • v.2 no.1
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    • pp.37-43
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    • 2003
  • Purpose: This study is to analyse the injury patterns of knee ligament and the factors influencing ligament injuries of knee, and to evaluate the changes of knee function and activity after ski injury. Materials and Methods: Thirty cases of ligament injuries of knee were studied with a questionaire, stress radiographs, magnetic resolution imaging, and physical examination. Mean age was 28.6 years old and mean follow up was 29.6 months. Clinical evaluation of Lysholm knee scoring scale was used for knee function and Tegner activity score was used for activity change after ski injury. Results: The anterior cruciate ligament (ACL) injury accompanied with medial collateral ligament(MCL) injury was most in 11 cases and isolated MCL injury was the next in 9 cases. The common types of injury mechanism were Phantom foot phenomenon (13 cases, 43$\%$) and valgus external rotation injury (12 cases, 40$\%$), which constitute 83$\%$ of all case. At the last follow up, the mean Lysholm score was 93.4 and mean Tegner activity score was 4.2. The reduced Tegner activity score after injury was 1.9. Among several injury groups, the evaluation of knee function and activity was best in the isolated MCL injury group and worst in the ACL injury accompanied with MCL injury group. The factors to influence ski injury were participation to ski class, release of binding, and skiing long time more than 2 hours. Conclusions: Lysholm score at last follow up revealed good grading, but sports activity after ski injury was reduced when compared with pre-injury state. It seems to need a active, systemic sports rehabilitation program after sports injury.

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Cascade Composition of Translation Rules for the Ontology Interoperability of Simple RDF Message (단순 RDF 메시지의 온톨로지 상호 운용성을 위한 변환 규칙들의 연쇄 조합)

  • Kim, Jae-Hoon;Park, Seog
    • Journal of KIISE:Databases
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    • v.34 no.6
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    • pp.528-545
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    • 2007
  • Recently ontology has been an attractive technology along with the business strategy of providing a plenty of more intelligent services. The essential problem in application domains using ontology is that all members, agents, and application programs in the domains must share the same ontology concepts. However, a variety of mobile devices, sensing devices, and network components manufactured by various companies, a variety of common carriers, and a variety of contents providers make multiple heterogeneous ontologies more likely to coexist. We can see many past researches fallen into resolving this semantic interoperability. Such methods can be broadly classified into by-mapping, by-merging, and by-translation. In this research, we focus on by-translation among them which uses a translation rule directly made between two heterogeneous ontology data like OntoMorph. However, the manual composition of the direct translation rule is not convenient by itself and if there are N ontologies, the direct method has the rule composition complexity of $O(N^2)$ in the worst case. Therefore, in this paper we introduce the cascade composition of translation rules based on web openness in order to improve the complexity. The research result made us recognize some important factors in an ontology translation system, that is speediness of translation, and conveniency of translation rule composition, and some experiments and comparing analysis with existing methods showed that our cascade method has more conveniency with insuring the speediness and the correctness.