• 제목/요약/키워드: exception analysis

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블랙홀 공격이 있는 MANET에서 VoIP 트래픽의 전송성능 (Transmission Performance of VoIP Traffic under Blackhole Attacks on MANET)

  • 김영동
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2011년도 추계학술대회
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    • pp.637-640
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    • 2011
  • 최근 스마트폰의 급속한 보급에 따라 기지국과 같은 기반구조를 사용하지 않은 MANET(Mobile Ad-Hoc Network)의 활용이 늘어날 것으로 예상되며, 인터넷 전화로 알려진 VoIP는 MANET의 주요 응용서비스 가운데 하나가 될 것으로 생각된다. 한편, 최근 문제점이 심각하게 부각되고 있는 정보침해의 경우, MANET에서도 예외일수는 없다. 특히, 군사적 목적이나 구난 구조와 같은 긴급 목적으로 사용이 가능한 MAENT에 대한 정보침해는 다른 네트워크에 비해 매우 치명적인 결과를 초래할 위험성을 내포하고 있다. 본 논문에서는 이런 문제점을 규명해보고자 블랙홀 공격이 있는 MANET에서 정보침해가 전송성능에 미치는 영향을 분석해 본다. 분석대상 서비스로는 VoIP 트래픽을 가정하였으며, 분석방법으로 NS-2를 사용한 컴퓨터 시뮬레이션을 활용한다.

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항적자료를 활용한 항공기 연료 소모량 추정 및 정확도 분석 (Estimation of Flight Fuel Consumption Based on Flight Track Data and Its Accuracy Analysis)

  • 박장훈;구성관;백호종
    • 한국항공운항학회지
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    • 제22권4호
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    • pp.25-33
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    • 2014
  • As global warming becoming an environmentally serious issue, more attention is drawn to fuel consumption which is the direct source of green house gas emission. The fuel consumption by aircraft operation is not an exception. Motivated by the societal and environmental context, this paper explains a method for estimation of aircraft fuel consumed during their flights as well as the computational process using real flight track data. Applying so-called 'Total Energy Model' along with aircraft specific parameters provided in EUROCONTROL's Base of Aircraft Data (BADA) to aircraft radar track data, we estimate fuel consumption of individual aircraft flown between Gimpo and Jeju airports. We then assess the estimation accuracy by comparing the estimated fuel consumption with the actual one collected from an airline. The computational results are quite encouraging in that the method is able to estimate the actual fuel consumption within ${\pm}6{\sim}11%$ of error margin. The limitations and possible enhancements of the method are also discussed.

Human Taeniasis in the Republic of Korea: Hidden or Gone?

  • Chai, Jong-Yil
    • Parasites, Hosts and Diseases
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    • 제51권1호
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    • pp.9-17
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    • 2013
  • History and current status of human taeniasis in the Republic of Korea, due to Taenia solium, Taenia asiatica, and Taenia saginata, are briefly reviewed. Until the 1980s, human taeniasis had been quite common in various localities of Korea. A study from 1924 reported 12.0% egg prevalence in fecal examinations. Thereafter, the prevalence of Taenia spp. ranged from 3% to 14% depending on the time and locality. Jeju-do, where pigs were reared in a conventional way, was the highest endemic area of taeniasis. An analysis of internal transcribed spacer 2 and mitochondrial cytochrome c oxidase 1 genes of 68 taeniasis cases reported from 1935 to 2005 in Korea by a research group revealed the relative occurrence of the 3 Taenia spp. as follows: T. solium (4.4%), T. asiatica (75.0%), and T. saginata (20.6%). However, national surveys on intestinal helminths conducted every 5 years on randomly selected people revealed that the Taenia egg prevalence dropped from 1.9% in 1971 to 0.02% in 1997 and finally to 0.0% in 2004. With the exception of 3 egg-positive cases reported in 2008 and 2 worm-proven cases in 2011, no more cases have been officially recorded. Based on these surveys and also on other literature, it can be concluded that taeniasis has virtually disappeared from Korea, although a few sporadic cases may remain hidden. Human cysticercosis is also expected to disappear within a couple of decades in Korea.

A Comparative Research of Library Law in Korea and Japan: Focusing on the Enactment and Revision Processes

  • 류현숙
    • 한국문헌정보학회지
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    • 제51권1호
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    • pp.103-124
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    • 2017
  • Korea and Japan have been influenced by one another through various points in their respective histories. During ancient times and throughout the Middle Ages, many aspects of culture and modern civilisation were conveyed from China to Japan via Korea. This trend changed in the second half of the $19^{th}$ century, as Japan opened its ports to foreign trade, completely reforming its own society before Korea followed suit. The aspects of modern civilisation and culture were thus subsequently conveyed to Korea from Japan. Not unlike Western cultures of the time, Japan also engaged in a pursuit of imperialism that resulted in its subjugation of Korea during the Japanese occupation. After Korea regained its independence following the Second World War, Koreans rebuilt their country largely on the basis of the social system Japan had left behind. 70 years later, differences from the Japanese model may nevertheless be observed in various areas. Library legislation is no exception. This paper provides a comparison of Korean and Japanese library laws. The comparison and consideration of the enactment and revision processes of library legislation of both countries reveals how differences in legislation developed and provides an analysis of the implementation of these differences.

Antioxidant Activity of Fractions from 70% Methanolic Extract of Sonchus oleraceus L.

  • Yin, Jie;Heo, Seong-Il;Jung, Mee-Jung;Wang, Myeong-Hyeon
    • Food Science and Biotechnology
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    • 제17권6호
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    • pp.1299-1304
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    • 2008
  • The potential antioxidant activities of different fractions from a 70% methanolic (MeOH) extract of Sonchus oleraceus were assayed in vitro. All of the fractions exception of n-hexane showed a strong antioxidant activity, especially the ethyl acetate (EtOAc) fraction, which showed the highest 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity ($IC_{50}=19.25{\mu}g/mL$). The results of hydroxyl radical scavenging activity and a reducing power assay showed concentration dependence, the EtOAc fraction demonstrating a better result than the other fractions at the same concentration in the studies. Additionally, the fractions' total phenolic (TP) contents was measured, phenolic compounds such as tannic acid, p-coumatric acid, quercetin, epicathchin, and kaempferol being detected by high performance liquid chromatography (HPLC). Meanwhile, a regression analysis revealed a moderate-to-high correlation coefficient between the antiradical activity and the TP contents, suggesting that fractions obtained from the 70% MeOH extract of S. oleraceus are of potential use as sources of antioxidant material.

초등학교 급식소에서 제공되는 닭고기 주요리의 급식품질 확보를 위한 HACCP 시스템 적용연구 (HACCP System Application on Chicken Entrees Served by Lunch Program of Elementary Schools)

  • 조경동;이복희
    • 한국식품조리과학회지
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    • 제20권1호
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    • pp.63-75
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    • 2004
  • This study was conducted to establish the hygiene standards for chicken entrees (deep-fried breast chicken, chicken and potato in red pepper paste and smothered chicken) served with in 3 different elementary school lunch programs during 2002. The study evaluated the layout characteristics of the food facilities, and determined the physical and microbiological hazards for the production of chicken entrees based on the HACCP(Hazard Analysis Critical Control Point) system. The kitchen layouts needed to be remodeled for the separation of soiled and clean work areas. The pH values for all items were over 6.0, which require careful attention. The microbial assessments of 3 chicken items revealed that the TPC, coliforms and Staphylococcus aureus were within normal ranges, but Salmonella was found at several stages in the production of all products, with the exception of smothered chicken. The bacterial counts of the kitchen utensils and cooks' hands exceeded acceptable limits, and workers' sanitary practices were poor in terms of sanitary handling and holding of foods and utensils. The CCPs determined related to the steps of receiving, cooking and breaking of egg shells. From our findings, it is recommended that chicken entrees should be prepared and served very carefully, as salmonella was detected at several stages during meal production, and the aim of the HACCP system is to secure against food-borne illnesses due to reckless school food service operations.

Esterel에서 근사-제어 흐름그래프의 효율적인 생성 (Efficient Construction of Over-approximated CFG on Esterel)

  • 김철주;윤정한;서선애;최광무;한태숙
    • 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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    • 제15권11호
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    • pp.876-880
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    • 2009
  • 프로그램에 대한 자료흐름분석(data flow analysis)를 수행하기 위해서는 입력된 프로그램에 대응하는 제어흐름그래프(control flow graph)가 필요하다. 본 논문에서는 동기(synchronous)식 절차(imperative)형 언어 중 하나인 Esterel로 작성된 프로그램에 대해서 단순하면서 입력 프로그램의 구조와 흡사한 형태로 표현되는 근사-제어흐름그래프(over-approximated CFG) 생성방법을 제안한다. 제안된 방법을 이용하면 병렬 제어흐름을 표현하는 부분에서 실행 불가능한 경우까지 포함할 수 있다. 그렇지만, 생성방법이 직관적이고, 실제 수행경로를 모두 포함하기 때문에 다른 분석을 수행하는데 매우 적차하다.

Leading for Safety: A Question of Leadership Focus

  • Molnar, Malin Mattson;Schwarz, Ulrica Von Thiele;Hellgren, Johnny;Hasson, Henna;Tafvelin, Susanne
    • Safety and Health at Work
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    • 제10권2호
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    • pp.180-187
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    • 2019
  • Background: There is considerable evidence that leadership influences workplace safety, but less is known about the relative importance of different leadership styles for safety. In addition, a leadership style characterized by an emphasis and a focus on promoting safety has rarely been investigated alongside other more general leadership styles. Methods: Data were collected through a survey to which 269 employees in a paper mill company responded. A regression analysis was conducted to examine the relative roles of transformational, transactional (management-by-exception active; MBEA), and safety-specific leadership for different safety behavioral outcomes (compliance behavior and safety initiative behaviors) and for minor and major injuries. Results: A safety-specific leadership contributed the most to the enhanced safety of the three different kinds of leadership. Transformational leadership did not contribute to any safety outcome over and above that of a safety-specific leadership, whereas a transactional leadership (MBEA) was associated with negative safety outcomes (fewer safety initiatives and increased minor injuries). Conclusion: The most important thing for leaders aiming at improving workplace safety is to continuously emphasize safety, both in their communication and by acting as role models. This highlights the importance for leadership training programs aiming to improve safety to actually focus on safety-promoting communication and behaviors rather than general leadership. Furthermore, an overly monitoring and controlling leadership style can be detrimental to attempts at achieving improved workplace safety.

A Case Study on Smart Concentrations Using ICT Convergence Technology

  • Kim, Gokmi
    • International journal of advanced smart convergence
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    • 제8권1호
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    • pp.159-165
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    • 2019
  • '4th Industrial Revolution' is accelerating as a core part of creating new growth engines and enhancing competitiveness of businesses. The fourth industrial revolution means the transformation of society and industries that are brought by IoT (Internet of Things), big data analysis, AI (Artificial Intelligence), and robot technology. Information and Communication Technology (ICT), which is a major factor, is affecting production and manufacturing systems and as ICT technologies become more advanced, intelligent information technology is generally utilized in all areas of society, leading to hyper-connected society where new values are created and developed. ICT technology is not just about connecting devices and systems and making smart, it is about constantly converging and harmonizing new technologies in a number of fields and driving innovation and change. It is no exception to the agro-fisheries trade. In particular, ICT technology is applied to the agricultural sector, reducing labor, providing optimal environment for crops, and increasing productivity. Due to the nature of agriculture, which is a labor-intensive industry, it is predicted that the ripple effects of ICT technologies will become bigger. We are expected to use the Smart Concentration using ICT convergence technology as a useful resource for changing smart farms, and to help develop new service markets.

기후변화를 통한 코로나바이러스감염증-19 추정 및 분류: 2018년도 이후 기상데이터를 중심으로 (Estimation and Classification of COVID-19 through Climate Change: Focusing on Weather Data since 2018)

  • 김윤수;장인홍;송광윤
    • 통합자연과학논문집
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    • 제14권2호
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    • pp.41-49
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    • 2021
  • The causes of climate change are natural and artificial. Natural causes include changes in temperature and sunspot activities caused by changes in solar radiation due to large-scale volcanic activities, while artificial causes include increased greenhouse gas concentrations and land use changes. Studies have shown that excessive carbon use among artificial causes has accelerated global warming. Climate change is rapidly under way because of this. Due to climate change, the frequency and cycle of infectious disease viruses are greater and faster than before. Currently, the world is suffering greatly from coronavirus infection-19 (COVID-19). Korea is no exception. The first confirmed case occurred on January 20, 2020, and the number of infected people has steadily increased due to several waves since then, and many confirmed cases are occurring in 2021. In this study, we conduct a study on climate change before and after COVID-19 using weather data from Korea to determine whether climate change affects infectious disease viruses through logistic regression analysis. Based on this, we want to classify before and after COVID-19 through a logistic regression model to see how much classification rate we have. In addition, we compare monthly classification rates to see if there are seasonal classification differences.