• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1474-1478
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• 2007

수문 및 수질자료는 일정한 기준에 의한 관측치를 시계열 자료로 기록하거나 전송할 때 다양한 형태의 오차가 발생하게 되며 또한 수문 및 수질자료를 관측하는 측정기기의 고장과 유지관리 등의 어려움으로 다양한 형태의 결측 자료가 발생하고 있다. 이와 더불어 수문 및 수질자료는 시공간적 변동성이 크며 비선형성이 강한 특성을 갖고 있다. 이러한 수문 및 수질 자료를 이용하여 모형을 구축할 경우 다양한 형태의 잡음에 대한 검증 및 잡음저감이 필수적 요건이라 할 수 있다. 따라서 본 연구에서는 영산강 유역의 본류부를 대표하는 나주지점에 대한 유출량과 총유기탄소(TOC) 농도 및 TOC 부하량 예측모형을 개발하였으며, 이를 위한 방법으로는 잡음저감을 위하여 웨이블렛 변환과 인공신경망을 적용하였다. TOC 부하량 자료는 유출량과 TOC 자료간의 함수로서 표현이 가능함에 따라 유출량 및 TOC 자료가 결측되었을 경우 역함수에 의한 계산으로 결측 자료에 대한 보간이 가능하다. 따라서 본 연구의 주안점은 잠음 저감 및 인공신경망에 의해 최적화된 예측 모형이 결측된 유출량과 TOC 자료에 대한 역함수로 정도있는 유출량과 TOC 자료 생성 가능성을 검토하고자 한다. 본 연구의 적용 결과, 유출량 자료가 결측되었을 경우 TOC 및 TOC 부하량 예측으로 유출량 자료에 대한 간접추정 및 결측 자료에 대한 보간의 정도를 평가한 결과 $R^2$는 0.99 이상의 값을 보였다. 또한, TOC 자료가 결측되었을 경우 역시 $R^2$는 비교적 우수한 0.97 이상의 값을 보였다. 따라서 본 연구에서 개발한 유출량 및 TOC, TOC 부하량 예측모형의 개발은 정도있는 유출량 및 TOC 수질 자료의 생성이 가능할 것으로 기대된다.한 물순환 해석을 할 수 있는 기반을 확보 하였으며, 가용한 장 단기간의 관측자료와 물수지 분석 연산식의 추정치를 바탕으로 관측자료에 의한 물수지 분석을 수행하였다. 분석 결과로 산지 소하천 유역인 설마천 시험유역의 각 수문요소의 물이동간의 정량적인 값을 알 수가 있었으며, 앞으로 추가적이고 지속적인 수문모니터링이 운영되고 물순환 해석 모형에 의한 검증이 수행된다면 정량적인 물순환 관계를 규명할 수 있을 뿐만 아니라 이와 관련된 수문요소기술을 확보할 수 있을 것이다.절한 타협과 조정을 필요로 한다. 그러나 절제의 한계를 넘어선다고 생각되거나, 조정의 노력이 불가능하거나, 실패했을 때 폭력적인 행동으로 나타나게 된다. 리차즈(I.A Richards)는 분노와 공포는 일단 겉잡을 수 없는 경향이 있다고 하면서 오늘날 폭력에 대한 요구가 일상의 정서 생활에 있어, 억압을 통한, 빈곤함을 반영하고 있지 않은지 생각해봐야 할 것이라고 충고한다. 조성 가이드라인(안)을 제시하였다.EX>$\ulcorner$세종실록$\lrcorner$(世宗實錄) $\ulcorner$지리지$\lrcorner$(地理志)와의 비교를 해보면 상 중 하품의 통합 9개소가 삭제되어 있고, $\ulcorner$동국여지승람$\lrcorner$(東國與地勝覽) 에서는 자기소와 도기소의 위치가 완전히 삭제되어 있다. 이러한 현상은 첫째, 15세기 중엽 경제적 태평과 함께 백자의 수요 생산이 증가하자 군신의 변별(辨別)과 사치를 이유로 강력하게 규제하여 백자의 확대와 발전에 걸림돌이 되었다. 둘째, 동기(銅器)의 대체품으로 자기를 만들어 충당해야할 강제성 당위성 상실로 인한 자기수요 감

• The KIPS Transactions:PartA
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• v.18A no.5
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• pp.193-204
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• 2011

Since web applications are accessed by anonymous users via web, more security risks are imposed on those applications. In particular, because security vulnerabilities caused by insecure source codes cannot be properly handled by the system-level security system such as the intrusion detection system, it is necessary to eliminate such problems in advance. In this paper, to enhance the security of web applications, we develop a static analyzer for detecting the well-known security vulnerability of PHP file inclusion vulnerability. Using a semantic based static analysis, our vulnerability analyzer guarantees the soundness of the vulnerability detection and imposes no runtime overhead, differently from the other approaches such as the penetration test method and the application firewall method. For this end, our analyzer adopts abstract interpretation framework and uses an abstract analysis domain designed for the detection of the target vulnerability in PHP programs. Thus, our analyzer can efficiently analyze complicated data-flow relations in PHP programs caused by extensive usage of string data. The analysis results can be browsed using a JAVA GUI tool and the memory states and variable values at vulnerable program points can also be checked. To show the correctness and practicability of our analyzer, we analyzed the source codes of open PHP applications using the analyzer. Our experimental results show that our analyzer has practical performance in analysis capability and execution time.

• Journal of the Economic Geographical Society of Korea
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• v.22 no.4
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• pp.555-575
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• 2019

Though housing market varies spatially, housing policy is limited in reflecting detailed regional differentiation. This study looked at the differences in Seoul Gu Districts' response to housing policy for the efficient implementation of housing policies in the future. Housing policy index was established by each Gu-districts' according to investigated housing policies from 2003 to 2018, weighted in two categories(financial/urban planning) and the status of designated areas. The VECM model was established to analyze the impact of the housing policy on the housing market. According to the analysis, although housing policies were established in response to market prices change, the impact of policies on prices was lower than the impact of vice versa. The housing policy's impact to the housing market is limited in some areas in northeastern Seoul. These results show that there are differences in the responses to housing policy in Seoul districts', and therefore detailed consideration of the differences in the regional aspects of housing policy is needed.

• Journal of the Korean Institute of Landscape Architecture
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• v.42 no.2
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• pp.41-51
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• 2014

A self-administered questionnaire survey and face-to-face interviews were conducted on 150 local residents belonging to seven villages, 160 visitors and 86 experts in order to analyze the attitudes of groups of local residents, visitors as well as experts toward the development plan of Sobaeksan Jarak-gil. Reliability analysis and one-way ANOVA were performed on the data collected by a questionnaire survey using IBM SPSS Statistics 20.0 after coding. The Duncan Test was conducted as a post-hoc test. Based on the analytical results, in economic terms, the expert group expected an increase in income, improvement in living standards and increase in expenditure for the maintenance of local infrastructure. In environmental terms, the visitor group was highly concerned about the disruption of the local natural environment and ecosystem, destruction of local properties and landscape, increase in water/soil/air pollution and increase in solid waste and noise. In social and cultural terms, the expert group had higher expectation for excavation of traditional cultural properties, instillation of local patriotism and pride, and the visitor group was highly concerned about a rise in crime, destruction of indigenous culture/increase in imitations, and induction of conflicts between residents. It is estimated that these results will be used as basic data for establishing the development plan of the mountainous ecological trail reflecting opinions of various groups.

• Journal of the Korean Society for Library and Information Science
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• v.51 no.1
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• pp.29-47
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• 2017

The purpose of this study is to compare and analyze the inquiry tasks included in the elementary social studies with school library based instruction (SLBI) focused on the information literacy process and select teacher librarians' educational role under learning for social studies. For this purpose, national elementary curriculum of $4^{th}$, $5^{th}$ and $6^{th}$ social studies in the second term are analyzed. As results of analysis, the $4^{th}$ and $5^{th}$ students who take part in solving the inquiry tasks could compare and analyze illustrations, photographs and texts in their text books individually and present the results with speaking. The $6^{th}$ students could deal with their tasks using their experience, idea or information found from other resources and express the outcome orally according to the content of inquiry tasks. Therefore, teacher librarians could teach information literacy skills such as comparison, contrast, combination, distinction between opinions and facts, or prediction and inference of conclusion to the $4^{th}$ and $5^{th}$ elementary student. Teacher librarians can also participate in whole information literacy instruction for the $6^{th}$ students from building the solution strategies of tasks, collecting and using materials to completing and evaluating the results under the long term collaboration with the classroom teachers.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.10
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• pp.6860-6868
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• 2015

In this study, we consider a problem of forecasting daily city gas demand of Korea. Forecasting daily gas demand is a daily routine for gas provider, and gas demand needs to be forecasted accurately in order to guarantee secure gas supply. In this study, we analyze the time series of city gas demand in several ways. Data analysis shows that primary factors affecting the city gas demand include the demand of previous day, temperature, day of week, and so on. Incorporating these factors, we developed a multiple linear regression model. Also, we devised a sampling procedure that selectively collects the past data considering the characteristics of the city gas demand. Test results on real data exhibit that the MAPE (Mean Absolute Percentage Error) obtained by the proposed method is about 2.22%, which amounts to 7% of the relative improvement ratio when compared with the existing method in the literature.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.5C
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• pp.496-512
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• 2007

In this paper, we propose a novel JPEG-2000 compressed image retrieval system using feature vector extracted through partial entropy decoding. Main idea of the proposed method is to utilize the context information that is generated during entropy encoding/decoding. In the framework of JPEG-2000, the context of a current coefficient is determined depending on the pattern of the significance and/or the sign of its neighbors in three bit-plane coding passes and four coding modes. The contexts provide a model for estimating the probability of each symbol to be coded. And they can efficiently describe texture images which have different pattern because they represent the local property of images. In addition, our system can directly search the images in the JPEG-2000 compressed domain without full decompression. Therefore, our proposed scheme can accelerate the work of retrieving images. We create various distortion and similarity image databases using MIT VisTex texture images for simulation. we evaluate the proposed algorithm comparing with the previous ones. Through simulations, we demonstrate that our method achieves good performance in terms of the retrieval accuracy as well as the computational complexity.

• Journal of Advanced Navigation Technology
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• v.23 no.5
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• pp.460-465
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• 2019

In this study, we aim to derive a solution from the structural analysis for electrical failure of single board computers for computing navigation information. By analyzing the characteristic factor, we identify that crack occur on the central processing unit board due to a certain structural problem, and that the physical effect by the crack make communication function be impossible to perform, which it causes booting error. In order to find the location of excessive stress causing the crack, structural analysis for the single board computer is done. From the structural analysis, the areas where stress concentration occurs are identified, and improvement methods changing the structures are developed. As a result, we shows that stresses are reduced entirely on the stress distribution for the improved structure. In addition, heat analysis shows that changing the structure to reduce stresses is not affect to the heat radiation, and the thermal resistance of the actual equipment is verified by measuring the temperature of the heat sink applied with the improved structure.

• Food Science and Preservation
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• v.24 no.2
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• pp.312-319
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• 2017

In the present study, disinfection efficacy of slightly acidic electrolyzed water [SlAEW, 30 ppm of effective chlorine at $20{\pm}1^{\circ}C$, oxidation-reduction potential (ORP) $562{\pm}23mV$, pH 6.4] on 4 kinds of vegetables (lettuce leaf, endive leaf, perilla leaf and kale leaf) was evaluated to obtain a microbial reduction characteristics which are necessary to design a process control for non-thermal sterilization of fresh vegetables. Active chlorine, residual chlorine, microbial counts and residual microbial counts, which are the key factors in the non-thermal sterilization process were measured by dipping them in SlAEW three times for 30 minutes in order to analyze the relationship between factors. Total microbial count was decreased mostly during the first 10 minutes of washing, and the limit value that can be reduced by immersion treatment was 3 log CFU/g for the total microbial count surviving in 4 kinds of vegetables. The total number of microorganism that can be reduced by washing in SIAEW for 10 min was found to be about 2 log CFU/g on average. In addition, the active chlorine decreased in the initial 10 minutes in 2.2 ppm, 2.0 ppm, 1.7 ppm and 2.5 ppm in lettuce, perilla leaf, endive leaf and kale leaf, respectively, and about 50-80% of the chlorine was reduced in the initial 10 min appear.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.4
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• pp.145-160
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• 2023

The purpose of this study was to compare and analyze diurnal thermal environments using Unmanned Aerial Vehicles(UAV)-derived physical parameters(NDVI, SVF) and ENVI-met modeling. The research findings revealed significant correlations, with a significance level of 1%, between UAV-derived NDVI, SVF, and thermal environment elements such as S↑, S↓, L↓, L↑, Land Surface Temperature(LST), and Tmrt. In particular, NDVI showed a strong negative correlation with S↑, reaching a minimum of -0.52^** at 12:00, and exhibited a positive correlation of 0.53^** or higher with L↓ at all times. A significant negative correlation of -0.61^** with LST was observed at 13:00, suggesting the high relevance of NDVI to long-wavelength radiation. Regarding SVF, the results showed a strong relationship with long-wave radiative flux, depending on the SVF range. These research findings offer an integrated approach to evaluating thermal comfort and microclimates in urban areas. Furthermore, they can be applied to understand the impact of urban design and landscape characteristics on pedestrian thermal comfort.