• 한국통신학회논문지
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• 제25권6B호
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• pp.1021-1027
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• 2000

In this paper, we propose two new detection-estimation based algorithms that effectively remove impulsive noises in severely corrupted color images. The existing methods for enhancing corrupted color images with impulsive noises commonly possess the inherent problems of excessive computing time and smoothing out edges. However, since our proposed algorithms classify corrupted pixels first in each channel or in each pixel and then perform marginal or vector median filtering only for them, are computationally efficient and preserve edges well. In addition, since there are no appropriate criteria to evaluate the performance of impulsive noise detectors for color images, the objective comparison of noise detectors is difficult. Thus, we introduce a new efficiency factor to compare the performance of noise detectors in digital color images. Simulation results show that the proposed algorithms perform better than the existing methods in terms of both objective and subjective evaluat ons.

• 반도체디스플레이기술학회지
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• 제22권1호
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• pp.99-103
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• 2023

NFT technology is mostly used to create digital drawings, characters, and items, and to simply buy and sell, but research and development to spread to various contents of NFT are somewhat marginal. Therefore, this study aims to solve the above-described problems. Depending on the exercise performance, it allows users to create and trade custom NFTs. In addition, it supports users to own customized digital works through exercise performance or to make money by trading them. Through it, the aim is to enhance users' positive interest in exercise and provide devices and methods for providing customized NFT creation and trading services that can help them develop exercise habits.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(1)
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• pp.11-12
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• 2005

With the great advances in process understanding, sensor and instrumentation technology and modelling capability it is important to ask what if any practical benefits can the lake manager and operator look forward to. Here, we examine some of the more important problems facing operators of drinking reservoirs, hydro-lakes and lakes used predominantly for recreation and the environment. In drinking reservoirs the main problems originate from increased loadings of nutrients leading to increased biomass and biomass that may give rise to toxins, of anthropogenic chemicals such as metals and synthetic organics and of pathogens of different types. Hydro-lakes are predominantly plagued by problems arising from low oxygen levels in the hypolimnion and in recreational and environmentally sensitive lakes the biggest challenge for the operator is to maintain an existing or establish a new trophic hierarchy or protect the water body from foreign species. The control variables that are at an operator's disposal are the choice of lake water level, the modification of the water colunm stratification via a de-stratification system, the modification of the lake flow path with flow intervention. curtains, intervention in the catchments to modify the loadings flowing into a lake, manipulation of the trophic chain with introduction of new species and chemical dosing, the latter being of marginal use in a large lake. Each of these options is cost effective under certain-circumstances. We endeavour to provide a users guide for their application and show how, especially new instrumentation and modelling methodologies may be used to achieve an effective intervention.

• 한국환경교육학회지:환경교육
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• 제10권2호
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• pp.51-62
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• 1997

The objective of this study was to review the meaning and problems of Scientific Knowledge and Ethical Value in Environmental Education. The ultimate goal of environmental education is shaping proenvironmental human behavior. The factors of human behavioral decision making are ideology, value, attitude and behavioral intentions. Ideology is a kind of belief system used by social groups to interpret their social world. The main elements of belief system are knowledge and value. The traditional thinking in education has been that we can change behavior by making human beings more knowledgeable and more valuable. In environmental education, the aim of scientific inquiry is to analysis cause-effect relation of human beings behavior and environmental phenomenon, and ethical education is to change the mind of human beings from zero-sum to positive-sum about the relations between human beings and natural environments. But, there are many problems of knowledge education and value education in environmental education. For example scientific knowledge without ethical value is dangerous to environment protection, and ethical value without scientific knowledge is vague. Therefore, we must recognize that the relationship of ethical value and scientific knowledge is not substitutional but complementary. The teaching-learning methods which can integrate knowledge and value in environmental education are rational decision making model. For this model, we can construct teaching contents with inquiry materials. To earn the benefits of specialization among several subjects in environmental education, social studies can focus on social science knowledge and decision making, science education can focus on pure natural science knowledge and scientific investigation, moral education can focus on problems of ethical value system, home economics can focus on practical action and environmental education(Environments in middle school, Ecology and Environments in high school) can integrate social-national science knowledge and ethical value in broad perspective about human beings and ecosystem. That is the method to protect from law of diminishing marginal utility of learning in environmental education.

• Journal of Plant Biotechnology
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• 제45권3호
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• pp.190-195
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• 2018

고구마는 21세기 인류가 당면한 식량, 에너지, 환경, 보건문제 등을 해결하는 21세기 구원투수로 등장하고 있다. 고구마는 식량자원 뿐만 아니라 바이오에탄올, 기능성 사료, 항산화물질 등 고부가가치소재를 생산하는 생체반응기로 평가된다. 미국 공익과학단체(The nonprofit Center for Science in the Public Interest, CSPI)는 고구마가 저분자항산화물질, 식이섬유, 칼륨 등을 고함유하고 있는 고구마를 몸에 좋은 10대 슈퍼식품 가운데 하나로 선정하였다. 미국 농무부는 고구마를 전분작물 가운데 식량수급에 영향을 최소화하는 척박한 토양에 가장 적합한 바이오에너지작물로 평가하였다. UN 식량농업기구는 2050년에 세계인구가 97억 명이 될 것이며 지금 추세로 식량을 사용하면 2050년에는 지금의 1.7배의 식량이 필요하다고 전망했다. 어떻게 미래 식량위기를 극복할 것인가? 이러한 측면에서 척박한 토양에서도 어느 정도 수량을 보장하는 고구마가 지구가 당면한 제반 문제를 해결할 수 있을 것으로 기대된다. 본 논문에서는 세계 고구마 유전자원과 생산현황을 살펴보고, 글로벌 식량자원 및 고부가가치 바이오소재 측면에서 새로운 고구마의 북방로드 개척 및 상업적 대량재배를 위한 선결과제를 기술하고자 한다.

• 한국사회복지학
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• 제62권1호
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• pp.343-365
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• 2010

본 연구는 북한이탈청소년의 문화변용 유형의 변동 추이를 추적하고 문화변용과 남한사회적응과의 관련성을 규명하는데 목적이 있다. 연구 참여자는 2003년 홍순혜 외의 연구(1차 조사)에 참여했던 90명의 9세-24세의 북한이탈청소년 중 추적이 가능했던 46명(2차 조사)이다. 1차 조사(2003) 결과 주변형이나 분리형이었던 북한이탈청소년의 약 37%는 2차 조사(2009)에서 동화형 또는 통합형으로, 동화형이나 통합형 중 약 21%는 주변형이나 분리형으로 전환된 것으로 나타났다. 남한문화 수용정도 및 북한문화 유지정도와 남한사회적응과의 관계를 분석한 결과, 남한문화 수용정도가 높을수록 심리사회적 문제는 적고 일상생활만족도는 높은 반면, 북한문화 유지성향이 높을수록 공격성이 높게 나타났다. 이상의 결과들을 중심으로 북한이탈청소년들의 문화변용 이해방안에 대한 논의를 전개하였으며 성공적인 남한사회적응을 위한 실천적, 정책적 대안들을 제시하였다.

• 상하수도학회지
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• 제23권6호
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• pp.743-752
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• 2009

One of the major problems associated with operation of domestic sewer lines involves hydraulic problems such as insufficient conveyance capacity, exceeding maximum velocity, and deficiency of minimum velocity. It has also been pointed out that influent concentration lower than design concentration of pollutants, which is mainly caused by unidentified inflow and infiltration, degrades the operational efficiency of many sewage treatment plants (STPs). A computer-added analysis method supporting a coupled simulation of sewage quality and quantity is essentially required to evaluate the status of existing STPs and to improve their efficiency by a proper sewer rehabilitation work. In this study, dynamic water quality simulations were conducted using MOUSE TRAP to investigate the principal parameters that governs the changes of BOD, ${NH_4}^+$, and ${PO_4}^{3-}$3- concentrations within the sewer networks based on data acquired through on-site and laboratory measurements. The BOD, ${NH_4}^+$ and ${PO_4}^{3-}$3- concentrations estimated by MOUSE TRAP was lower than theoretical pollution loads because of sedimentation and decomposition in the sewer. The results revealed that sedimentation is a most important factor than other biological reactions in decreasing pollutant load in the sewers of C-city. The sensitivity analysis of parameters pertaining to water quality changes indicated that the effect of the BOD decay rate, the initial DO concentration, the half-saturation coefficient of dissolved BOD, and the initial sediment depth is marginal. However, the influence of settling rate and temperature is relatively high because sedimentation and precipitation, rather than biological degradation, are dominant processes that affect water quality in the study sewer systems.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제33권5호
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• pp.435-439
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• 2011

Ameloblastoma is an aggressive benign odontogenic epithelial tumour that may arise from the enamel organ, remnants of dental lamina, or the lining of an odontogenic cyst. It is usually categorized into solid or multicystic, unicystic, and peripheral types. Treatment ofameloblastomas include conservative methods such as marsupialisation, enucleation, and curettage; and radical treatments such as marginal or segmental resection. Radical treatments have resulted in lower recurrence rates; however, may also encounter esthetic, functional, and reconstructive problems. Unicystic ameloblastoma has been considered less aggressive and a lower recurrence tendency. Thus, many authors have recommended conservative treatment in cases of unicystic ameloblastoma. An 11 year-old boy presented with displaced second and third molars by luminal unicystic ameloblastoma in the mandible. Cyst enucleation, curettage, and third molar extraction were done. No signs of recurrence or esthetic problems such as facial asymmetry were seen radiologically and clinically, up to 8 years 2 months postoperatively.

• 대한치과보철학회지
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• 제36권1호
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• pp.133-149
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• 1998

Clinical application of composite resin recently draw great concerns in dentistry. Especially due to advantages such as esthetics, adhesiveness, simple clinical procedures, various shapes and kinds of composite resins are widely being applied to prosthodontics, conservative dentistry, and orthodontics. But, clinical problems attributable to the polymerization shrinkage of composite resin have been proposed, and we have to regard clinical problems such as secondary caries, loss of restoration, fracture of the surrounding tooth structure, marginal discoloration, and tooth sensitivity, and many portions are remained to be overcome. Therefore, this study attempts to analyze stress distribution between resin and tooth structure which is generated during polymerization shrinkage of composite resin using three dimensional finite element method. Three dimensional finite element models with conventional box-shape cavity and erosion/abrasion type V-shape lesion cavity in upper central incisor were developed. These cavities were filled with four different types of placement techniques. (bulk filling, horizontal increment filling, oblique occlusal increment filling, oblique gingival increment filling) The stresses generated by polymerization shrinkage of composite resin were calculated. The results analyzed with three dimensional finite element method were as follows : 1. The increment filling technique showed the highest maximum normal stress in both conventional box-shape and V-shape cavities and showed a tendency to decrease after complete polymerization. 2. The bulk filling technique resulted in increased stresses during the curing process in both conventional box-shape and V-shape cavities and the highest maximum normal stress occurred after complete polymerization. 3. The bulk filling resulted in the lowest maximum normal stress in both box-shape and V-shape cavities 4. Regardless of placement method, in conventional box-shape cavity, the maximum normal stress increased in dentin floor, enamel, dentin sequence and in V-shape cavity, the maximum normal stress increased in enamel, dentin sequence.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제7권4호
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• pp.860-877
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• 2013

Cloud computing has become one of the most important technologies for reducing cost and increasing productivity by efficiently using IT resources in various companies. The cloud computing system has mainly been built for private enterprise, but public institutions, such as governments and national institutes, also plans to introduce the system in Korea. Various researches have pointed to security problems as a critical factor to impede the vitalization of cloud computing services, but they only focus on the security threats and their correspondents for addressing the problems. There are no studies that analyze major security issues with regard to introducing the cloud computing system. Accordingly, it is necessary to research the security factors in the cloud computing given to public institutions when adopting cloud computing. This research focuses on the priority of security solutions for the stepwise adoption of cloud computing services in enterprise environments. The cloud computing security area is classified into managerial, physical and technical area in the research, and then derives the detailed factors in each security area. The research derives the influence of security priorities in each area on the importance of security issues according to the identification of workers in private enterprise and public institutions. Ordered probit models are used to analyze the influences and marginal effects of awareness for security importance in each area on the scale of security priority. The results show workers in public institutions regard the technical security as the highest importance, while physical and managerial security are considered as the critical security factors in private enterprise. In addition, the results show workers in public institutions and private enterprise have remarkable differences of awareness for cloud computing security. This research compared the difference in recognition for the security priority in three areas between workers in private enterprise, which use cloud computing services, and workers in public institutions that have never used the services. It contributes to the establishment of strategies, with respect to security, by providing guidelines to enterprise or institutions that want to introduce cloud computing systems.