• 한국기후변화학회지
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• 제6권2호
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• pp.87-94
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• 2015

To compare changes in winter temperature over South Korea, 30-year average climate data and climate data of recent 10 years (2014~2014) such as mean temperature, daily maximum temperature and daily minimum temperature were analyzed. Also, we set analysis extreme cold waves frequency related to winter such as freezing days, snow days, days with temperature of below -5, and days with temperature of below -10. This process enabled the comparative analysis of winter temperature changes and extreme cold waves frequency related to winter. This study estimated that winter temperature has gradually increased throughout the last five decades, however, the frequency of extreme weather, such as cold waves has also increased.

• 한국대기환경학회:학술대회논문집
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• 한국대기환경학회 2008년도 추계학술대회 논문집
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• pp.168-170
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• 2008

• Asian Journal of Atmospheric Environment
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• 제8권3호
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• pp.140-153
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• 2014

The extreme heat watch and warnings (EHWW) which is constructed as a part of the climate change adaptation took effect in the summer of 2008, but active response actions failed to be taken because of low perception among citizens. Therefore, a survey investigation targeting citizens residing in Busan and the Gyeongnam province was conducted in order to know the perception regarding EHWW issued by the Korea Meteorological Administration, to identify the main media through which information is acquired, and to propose an improvement measures which may enhance the usefulness and the degree of satisfaction of weather information. The results are as follows; The perception regarding EHWW was not very high as it remained at 59.8% in terms of percentile. Although the statistical significance was not fulfilled in the categories of gender or occupation, significant differences did exist among age groups. The main medium through which citizens acquired information regarding EHWW was the television, which was followed in order by the internet, acquaintances, short message service (SMS), radio, newspapers, the 131 weather hotline, and other media. The usefulness of EHWW was somewhat high (67.2%), and female students were found to utilize the information to a higher degree than male students. The statistics on the level of satisfaction regarding the weather information (65.4%) revealed that most respondents were satisfied. Housewives, professional, and the elder age groups exhibited great satisfaction, leading to the conclusions that the level of perception and interest regarding to the special weather reports (SWR) have an impact on satisfaction of SWR.

• 대한수학교육학회지:수학교육학연구
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• 제11권1호
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• pp.51-66
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• 2001

In this paper, we tried to examine the didactical transpositions of the mathematical knowledges in the computer-based environment for mathematics learning and teaching, and also analyse the extreme didactical problems Computer has been regarded as an alterative that could overcome the difficulties in the teaching and learning of mathematics and many broad studies have been made to use computers in mathematics teaching and learning. But Any systematic analysis on the didactical problems of the computer-based environment for mathematics education has not been tried up to this time. In this paper, first of all, we analysed the didactical problems in the computer-based environment, and then, the mode of using computer for mathematics teaching and learning.

• 디지털산업정보학회논문지
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• 제18권3호
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• pp.97-110
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• 2022

The case study looks into the case of the "extreme" market segmentation strategy of company L with its top luxury windows and door brand "Lonchel". Company L has long enjoyed a leading position in the Korean windows and doors mass market. However, it went against their already well-established flagship brand and created a completely new one called "Lonchel", pursuing an extreme market segmentation strategy focusing on the small niche market of highest-income customers exclusively. The strategy has turned out to be successful and the company has gained long-lasting competitive advantages. In this vein this study analyzes the market environment in which the top-tier brand "Lonchel" appeared, the concept of the extreme positioning and the smallest viable market, the characteristics of target customers, the company's analysis of and response to them, and the analysis of products to meet their needs. The brand operation plan and promotion will be also reviewed. Through this, we intend to draw implications related to the extreme positioning strategy that a company may pursue in a target market of small groups of people.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권2호
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• pp.442-458
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• 2014

Wave induced vibrations increase the fatigue and extreme loading, but this is normally neglected in design. The industry view on this is changing. Wave induced vibrations are often divided into springing and whipping, and their relative contribution to fatigue and extreme loading varies depending on ship design. When it comes to displacement vessels, the contribution from whipping on fatigue and extreme loading is particularly high for certain container vessels. A large modern design container vessel with high bow flare angle and high service speed has been considered. The container vessel was equipped with a hull monitoring system from a recognized supplier of HMON systems. The vessel has been operating between Asia and Europe for a few years and valuable data has been collected. Also model tests have been carried out of this vessel to investigate fatigue and extreme loading, but model tests are often limited to head seas. For the full scale measurements, the correlation between stress data and wind data has been investigated. The wave and vibration damage are shown versus heading and Beaufort strength to indicate general trends. The wind data has also been compared to North Atlantic design environment. Even though it has been shown that the encountered wind data has been much less severe than in North Atlantic, the extreme loading defined by IACS URS11 is significantly exceeded when whipping is included. If whipping may contribute to collapse, then proper seamanship may be useful in order to limit the extreme loading. The vibration damage is also observed to be high from head to beam seas, and even present in stern seas, but fatigue damage in general is low on this East Asia to Europe trade.

• 한국정보통신학회논문지
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• 제7권6호
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• pp.1351-1359
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• 2003

극한 프로그래밍은 빠르게 변화되는 사업 환경에 기민하게 대응하는 애자일 소프트웨어 개발 방법론 중에서 가장 대표적인 방법론이다. 소프트웨어 산업이 성숙됨에 따라 소프트웨어 품질 요소중 사용성이 점차 강조되고 있으나, 극한 프로그래밍에서 사용성을 확보하기 위한 노력이 부족한 실정이다. 극한 프로그래밍의 사용성 향상을 위하여 본 논문에서는 소프트웨어 생명주기를 조사, 계획, 릴리즈 반복, 제품화, 유지보수, 사망의 6단계로 정의한다. 사용성 평가를 위한 통합시험과 인수시험을 포함한 11개의 활동을 정의하여 사용성을 향상시킬수 있는 극한 프로그래밍 프로세서를 제안한다. 제안한 프로세서의 타당성을 4가지 측면에서 확인하였다. 제안한 프로세스는 극한 프로그래밍 프로세스가 인수시험 활동을 지원하도록 개선하였으며, 극한 프로그래밍 프로세스가 CMM 레벨4를 지원하도록 하며, CMM 품질보증 실무를 지원하도록 하였다.

• 한국해양환경ㆍ에너지학회지
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• 제1권2호
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• pp.71-81
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• 1998

이 논문에서는 홍도와 마라도에서의 파랑의 통계적 특성을 살펴보았다. 두 지역에서의 스펙트럼법과 시계열에서 얻은 유의파고를 이용하여 파고주기결합분포를 얻었으며 여러 가지 통계적인 특성을 살펴보았다. 주파수의 대역폭이 협대역이 아닌 경우에 개별 파고분포에 롱기히긴스가 제안한 수정레일리분포를 사용할 수 있다. 그러나 이 분포함수는 경험상수를 결정해야하는 불편함 때문에 널리 사용되지 않고 있었다. 본 논문에서는 수정레일리분포의 경험상수를 결정하는 간단한 방법을 제안하였다. 설계파고의 추정에서 서로 다른 분포함수 선택에 따른 영향은 크지 않다. 그러나 스펙트럼법과 시계열에서 얻은 파랑자료 사용에 따라서 한계파고의 추정치는 큰 차이를 보인다.

• 한국환경과학회지
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• 제24권9호
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• pp.1199-1210
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• 2015

There were 35 typhoons affecting Korean Peninsula from 1999 to 2009(The average annual number of typhoon is 3.18). Among these typhoons, the number of typhoon passing through the Yellow sea, the Southern sea and the East sea were 14, 6 and 15 respectively. Wind speed on the height of 10 m can be finally estimated using the surface roughness after we calculate wind speed on the height of 300 m from the data on the surface of 700 hPa. From the wind speeds on the height of 10 m, we can understand the regional distributions of strong wind speed are very different according to the typhoon tracks. Wind speed range showing the highest frequency is 10~20 m/s(45.69%), below 10 m/s(30.72%) and 20~30 m/s(17.31%) in high order. From the analysis of the wind speed on the hight of 80 m, we can know the number of occurrence of wind speed between 50 and 60 m/s that can affect wind power generation are 104(0.57%) and those of between 60 and 70 m/s that can be considered as extreme wind speed are even 8(0.04%).

• 한국공간구조학회논문집
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• 제18권3호
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• pp.67-74
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• 2018

Recently, measuring instruments for SHM of structures has been developed. In general, the wireless transmission of sensor signals, compared to its wired counterpart, is preferable due to the absence of triboelectric noise and elimination of the requirement of a cumbersome cable. However, in extreme environments, the sensor may be less sensitive to temperature changes and to the distance between the sensor and data logger. This may compromise on the performance of the sensor and instrumentation. Therefore, in this paper, free vibration experiments were conducted using wireless MEMS sensors at an actual site. Measurement was assessed in time and frequency domain by changing the temperature variation at($-8^{\circ}C$, $-12^{\circ}C$ and $-16^{\circ}C$) and the communication distance (20m, 40m, 60m, 80m).