• 한국구조물진단유지관리공학회 논문집
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• 제17권6호
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• pp.112-121
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• 2013

FRP 보강근을 사용한 경량콘크리트 구조체는 부식방지 및 자중감소의 효과를 동시에 기할 수 있는 이점이 있어서 추후 그 활용이 기대될 수 있다. 그러나 경량콘크리트와 FRP 보강근을 사용하여 보강근의 내부슬립 없이 외력에 저항할 수 있는 구조체를 만들기 위해서는 경량콘크리트와 FRP 보강근 사이의 부착특성을 파악하는 것이 대단히 중요하다. 그동안 보통콘크리트와 FRP 보강근 사이의 부착거동에 대하여는 많은 연구가 있어 왔으나 경량콘크리트와 FRP 보강근 사이의 부착거동에 대하여는 현재까지 연구결과가 대단히 부족한 실정이다. 따라서 본 연구에서는 경량콘크리트와 보강근 표면에 나선형태의 이형을 갖는 GFRP 보강근 사이의 부착특성을 조사하였다. 비교목적으로 보강근 종류, 콘크리트 종류, 경량콘크리트 강도종류의 실험변수를 고려하여 인발실험체들을 제작하고 실험을 행하였다. 실험분석 결과, 보통콘크리트와 철근을 사용한 실험체의 부착강도를 1.0으로 하였을 때 경량콘크리트와 나선형태의 이형을 갖는 GFRP 보강근을 사용한 실험체의 부착강도는 0.49로 나타났다.

• 한국치위생학회지
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• 제16권1호
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• pp.11-18
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• 2016

Objectives: The purpose of the study was to compare the oral health related characteristics between a long-term patients and general population. Methods: A direct interview questionnaire was completed by 160 patients and 165 general people from January 16 to April 31, 2014. The questionnaire consisted of general characteristics of the subjects, subjective health status, oral health behaviors, and needs of oral health. The data were analyzed using SPSS 18.0 program. Results: The long-term patients reported that most of them were denture wearers(38.1%), and had oral disease symptoms(62.5%) and xerostomia(65.6%). Most of the long-term patients were ex-smoker(31.3%) and did not receive regular dental check-up(92.5%). They did not know tooth brushing method(31.3%) and brushed their teeth less than twice a day(47.5%). Those who used tooth brush for more than 6 months accounted for 47.5%. Most of them did not use auxiliary oral hygiene devices(85.6%). The patients answered that oral health is not important(6.9%), oral health education is not necessary(7.5%), and oral cleaning(26.3%) should be included in oral health education. Conclusions: The self-reported oral health status of the long-term patients much more serious than the general population. It is necessary to educate the continuing oral health management program for the long-term patients.

• 지질공학
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• 제22권4호
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• pp.449-458
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• 2012

암반의 구조적 특성에 대한 확고한 이해는 지반구조물의 효과적인 설계 및 유지관리에 있어서 매우 중요한 요소이다. 이는 암반의 강도, 변형 및 수리지질학적 특성이 주로 암반에 존재하는 불연속면의 연결구조 특성에 좌우되기 때문이다. 그동안 암반의 구조적 특성에 대한 연구에 있어서 상당한 진전이 있었음에도 불구하고 불연속면 분포의 복잡성으로 인하여 암반의 삼차원적 구현 및 가시화에 기반한 지질공학적 해석은 드문 실정이다. 이 연구는 암반의 불연속면 및 불연속면의 연결구조를 삼차원적으로 구현하고 가시화하는 기법을 제시하였다. 이를 위하여 원판형으로 가정한 불연속면의 비선형 방정식을 유도하고 불연속면 교차선과 등가파이프의 위치를 산정할 수 있는 대수학적 알고리즘이 제시되었으며, 또한 연산과정을 수행하는 전산모듈이 작성되었다. 이 연구에서 개발한 불연속면 연결구조의 삼차원적 구현 및 가시화 기법은 불연속체 기반의 암반강도 및 변형성에 관한 연구 또는 수리지질학적 특성에 관한 연구를 수행함에 있어서 활용도가 높을 것으로 판단된다.

• 인터넷정보학회논문지
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• 제20권6호
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• pp.37-46
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• 2019

A test plan is a high level document detailing objectives, processes, schedules and so on for verifying a developed software. And a test strategy, a component of a test plan, is about how to test software products to guarantee its quality and find bugs in the software in advance. Therefore, establishing effective and suitable test strategies is important for elaborating test processes. However, these tasks are difficult for project managers who write a test plan if they were not trained well in software test processes. And mis-designed test strategies will also mislead entire testing behaviors that testers would do. As a result, there would be a low quality software product in the end. To solve this problem, we propose a new test strategy reuse technique in this paper. By utilizing test plans of already completed software development projects, we lead test planer to reuse suitable and effective test strategies which were used in previous projects. To do so, we evaluate existing test strategies by utilizing ISO/IEC 25010 quality model for evaluating the suitability of test strategies and also use effectiveness metrics for test strategies. And from these evaluations, we predict completeness of new test plan that is written by reused test strategies. It can help the project manager to write an appropriate test plan for the quality characteristics which are selected as objectives for testing and software product. We show the possibility of our approach by implementing a prototype into the existing framework in a case study.

• 한국주조공학회지
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• 제23권5호
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• pp.276-285
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• 2003

In the undercooled melt of $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy, the solidification behavior including nucleation and growth of crystals at the micrometer level has been observed in-situ by use of a confocal scanning laser microscope combined with an infrared image furnace. The $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy specimens were cooled from the liquid state to glass transition temperature. 575 K, at various cooling late under a helium gas flow. According to the cooling rate, the morphologies of the solidification front are changed among various types, irregular jog like front, columnar dendritic front, cellular grain, star like shape jog and fine grain, etc. The velocities of the solid-liquid interface are measured to be $10^{-5}{\sim}10^{-8}$ m/s which are at least two orders higher than the theoretical crystal growth rates. Combining the morphologies observed in terms of cooling rates and their solidification behaviors, we conclude that phase separation takes place in the undercooled molten $Pd_{40}Cu_{30}Ni_{10}P_{20}$ alloy. The continuous cooling transformation (CCT) diagram was constructed from solidification onset time at various linear cooling conditions with different rate. The CCT diagram suggests that the critical cooling rate for glassy solidification is about 1.5 K/s, which is in agreement with the previous calorimetric findings.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회 2차
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• pp.171-180
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• 2010

In this study, applicability of software used to analyze the lateral deformations and its shape of braced cuts, executed to excavate the ground for constructing the underground structures, was assessed by performing field measurements and numerical analyses and their behaviors were also compared with results of previous studies. Three typical sections, located at the construction site where the subway was on the process of construction at Suwon city in Gyeonggido, were chosen and the data of field measurement at those sections were collected. Numerical analyses with FEM technique of using the software PLAXIS and elasto-plastic approach of using the software MIDAS were performed. In general, the deformed shapes of braced cut, obtained from numerical approaches, were in relatively good agreements with results from field measurements. For sections of A-A and B-B, measured values were greater than analyzed ones whereas they were in relatively good agreements in the section C-C. As results of comparing the values from the measurements and the estimations, they were found to be close to each other so that numerical approaches were assessed to be appropriate to estimate the lateral deformation. The numerical technique with FEM was preferred to use because it estimated closer to the measurements than the elasto-plastic approach.

• 보건교육건강증진학회지
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• 제23권4호
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• pp.105-124
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• 2006

Objectives: This study examined the reproductive health status and the work-related factors of female hairdressers. Methods: This study conducted by structured questionnaire from April 21th to May 20th. The study population of 316 were female hairdressers aged 15 to 60 years in Seoul. This study analysed the influencing factors, health related factors and work related factors on reproductive health using chi-square and multiple logistic regression analysis. Results: 1. The 81.7% of the subjects aged under 29 years have unhealthy behaviors. The 47% of hairdressers experienced smoking. Among the total, 37% of them answered they are smoking at present. Those results reveal their working conditions were very stressful to cope as young females. 2. The use of hair dyes(OR=2.89, 95%CI:1.17-7.12), counteractive solutions(OR=3.20, 95%CI:1.04-9.83) and not wearing protective gloves(OR=2.81, 95%CI:1.11-7.12) are significantly associated with menstrual pains. 3. The hairdressers not using perm liquids were three times as likely to report regular menstruation compared with the hairdressers using perm liquids. Wearing protective gloves also was associated with regular menstruation. Conclusion: This study revealed various risky working conditions of hairdressers was associated with their reproductive health. This study suggests that we should pay more attention to the protective working conditions for reproductive health. More comprehensive health management program including reproductive health for female hairdressers is required as well.

• Korean Chemical Engineering Research
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• 제43권1호
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• pp.47-52
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• 2005

미립 금속분체에 대한 산업 수요 증가와 함께, 퇴적 금속분의 착화에 의한 화재, 폭발사고가 증가하고 있다. 본 연구에서는 퇴적 금속분체의 화재, 폭발 위험특성을 조사하기 위하여 새로운 실험장치를 개발하였다. 금속분(Mg, Zr, Ta, Ti) 및 PMMA(polymethyl methacrylate)분진을 사용하여, 연소 거동(소염거리, 화염전파속도) 및 화염전파에 미치는 $N_2$ 치환 분위기 농도의 영향 등을 실험적으로 상세히 조사하였다. 실험결과로부터, 퇴적 금속 분체의 화염전파속도는 PMMA보다 크고, 화염전파속도의 퇴적층 두께에 대한 의존성은 작으며, 질소 치환 분위기에서의 Mg의 한계 산소 농도는 3.6-3.7 vol%로 나타났다. 퇴적금속 분체층의 화염전파속도와 소염거리 역수는 높은 상관관계를 가지고 있으며, 이들 연소성 지표에 있어서 상대적인 위험성의 예측이 가능하다.

• 대한가정학회지
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• 제46권3호
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• pp.103-116
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• 2008

With increasing of communication technology in cyber-space, the space of consumer complain behavior moved from off-line to on-line, so called anti-site. No researches, however, really have done how the anti-sites worked for promoting consumer rights through consumer complain behaviors in cyber space. The purpose of this research was to give some suggestions for activating anti-site for promoting consumer rights. For this purpose, questionnaire on-line survey was conducted from April, 12 to 24, 2004. And 143 samples, who were visiting anti-site during survey period, were selected. Main findings were as following: First, visitors had rather positive confidence with informations in anti-sites. Second, visitors thought that anti-sites were working rather well in implementing consumer movement by sharing their experiences, and by supporting complaining space in cyber. Visitors, however, thought that anti-sites were not working well as a space for companies, not by giving their attentions on consumers' complains. Third, the satisfaction level of visitors was found to be rather high in terms of informations in anti-sites, and to be rather low in terms of companies' attentions on anti-sites and management of anti-sites. Based on results, some suggestions of activating anti-site for promoting consumer rights were as following: First, visitors should not only get information, but support new and useful informations for others. And also it was suggested that visitors should join consumer movement through anti-site actively. Second, companies should pay attentions on anti-sites for their sake because anti-sites could give very useful information improving customer satisfaction, and finally reducing cost and increasing profit.

• 한국게임학회 논문지
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• 제12권4호
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• pp.45-51
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• 2012

상호작용 증강현실 인터페이스는 실세계에 가상 정보를 혼합하여 사용자의 인식을 증강시킬 수 있으며 사용자에게 실세계에서 이용되는 오브제를 가상 게임에 그대로 제공함으로써 현실과 가상 환경을 자연스럽게 연계할 수 있다. 우리는 실생활과 가상 게임 환경과의 이음새 없는 환경을 위해 TCG(Trading Card Game; 이하 TCG로 약칭) 게임에 실제 카드를 적용하는 방안을 연구하였다. 스마트 폰 카메라를 통해 인식된 카드를 가상의 TCG 게임 인터페이스로 사용한다. 기존 연구에 비해 보다 빠르고 스케일, 방향, 포즈, 회전에 무관하게 실 카드를 인식하기 위해 2 단계 이미지 키포인트 추출/매칭 방법(Two Phases Image eyPoint Extraction/Matching Method)을 스마트폰 환경에서 개발하고 이것을 가상 TCG 게임 시스템에 실험적으로 적용하였다. 이와 같은 창의적인 시도는 현실과 가상 환경을 자연스럽게 연결하여 게임에의 몰입감과 현실감을 배가시킬 것이다.