• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.686-689
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• 2008

지난 10여 년간 건설 분야에서 데이터 마이닝(data mining) 기법을 이용하여 실적 데이터의 패턴을 찾고 이를 바탕으로 다양한 예측 모델을 개발하려는 연구들이 다수 진행되어 왔다. 그러나 데이터 마이닝 기법의 경우, 일반적으로 수천 또는 수만 개의 데이터를 사용할 것을 추천하고 있으나, 건설 분야의 선행연구들을 살펴보면 데이터 마이닝에 사용된 데이터의 수가 최대 이백 개 표본 정도에 그치고 있다. 그 결과 데이터 마이닝 기법을 이용하여 선행연구의 방법 및 결과를 재현하려고 하여도 같은 결과를 얻기 힘들고, 아예 패턴추출이 힘들거나 도출된 패턴에 오류가 있는 경우도 있다. 본 연구는 소수의 표본수에 기초하여 보다 신뢰성 있는 공법선정 모델의 개발에 관한 대안적인 방법을 모색하고자 한다. 먼저 건설 분야에서 데이터 마이닝 기법을 활용한 연구의 범위에 대해 살펴보고, 특히 흙막이 공법선정 모델 구축에 관한 선행연구 고찰을 통해 소수의 데이터에 의존함에 따라 발생하는 문제점들을 알아보고, 이를 극복할 수 있는 방안에 대해 논의 하고자 한다.

• 한국조경학회지
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• 제36권6호
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• pp.43-54
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• 2009

본 연구는 새롭게 조성되는 도시의 물순환체계를 구축하고, 도시화로 말미암아 증가하는 유출량을 분산 저류함은 물론, 생물다양성을 증진시킬 수 있는 습지의 조성입지와 면적을 확보하는 것에 중점을 두었다. 습지조성 입지선정을 위하여 유역분석에서부터 평가항목 선정, 가중치 산출, 주제도 작성, 종합 등 일련의 과정을 모형으로 정립하였다. 개발된 모형은 수도권에 입지해 있는 위례 신도시 개발예정지역에 적용함으로써 모형의 실행가능성과 한계를 검토하였다. 적용 결과, 유역분석단계 에서는 대상지가 13개의 소유역으로 구분되며, 개발대상지가 포함되는 유역들의 유입량은 $3,020,765m^3$인 것으로 나타났다. 개발 전 후의 유출량을 비교하면 각각 $1,901,969m^3$, $1,970,735{\sim}2,039,502m^3$로써 개발지역에서 확보해야 할 총 저류량은 $68,766{\sim}137,533m^3$로 산출되었다. 습지조성 입지선정단계에서는 각각의 주제도를 중첩한 결과, 13개 소유역별로 습지조성 우선지역이 차등적으로 분류되었다. 유출량을 저류할 수 있는 습지의 입지와 면적을 도출한 결과, 저류형 습지와 하천형 습지, 연못형 습지 등 다양한 유형의 습지조성은 물론 이들의 유기적 연계가 가능한 것으로 판단되었다. 이는 도시 전체의 물순환체계 계획의 기본골격을 제공함으로써 녹지공간과의 통합을 통해 도시생태 네트워크 계획 수립과 같은 공간계획단계에 유용하게 활용될 수 있을 것으로 판단되었다. 그러나 본 연구는 토지이용계획 이전 단계에서 도시화로 인해 예상되는 잠재적인 유출량을 기준으로 습지의 입지와 면적을 산정함에 따라 정확한 저류량의 산정을 위해서는 토지이용계획 이후 환류(feedback)과정이 요구되었으며, 습지의 유형이나 입지적 특성에 따라서 저류량 등 저류능력이 달라질 수 있음에도 불구하고 문헌에서 고찰되는 일반적인 습지 저류량을 모든 습지에 동일하게 적용했다는 점은 본 연구의 한계라 할 수 있다.

• 한국지반공학회지:지반
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• 제12권6호
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• pp.185-198
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• 1996

EPS(Expanded Polystyrene)를 이용한 하중경감공법은 초경량재(20~30kg/m3)인 EPS를 본 연구는 보강토 토류벽체의 뒤채움재로서 폐 EPS 조각을 혼합한 경량의 성토재료를 개발, 활용하기 위한 기초연구로서, 우리나라에 광범위하게 분포하는 화강풍화토와 폐 EPS조각을 혼합한 경량성토재에 대해 공학적 특성파악을 위한 기본물성시험을 수행하였고, 또한 국내에서 판매되고 있는 두가지 대표적인 강성 및 연성 지오그리드 보강재에 대해 폐 EPS조각의 혼합비를 변화시 켜가며 실내인발시험을 수행하였으며, 이들 시험결과를 토대로 하여 폐 EPS조각 혼합경량토의 토질공학적 특성과 지오그리드-혼합경량토 사이의 마찰특성을 분석.평가하였다. 또한 본 연구에서는, 인장력 이외에도 다짐하중 및 상재하중 등 수직하중에 의한 압축력이 추가로 동시에 작용하는 경우의 지오그리드의 인장력-변형률 관계를 고려할 수 있는 마찰강도 산정방법을 제시하였으며, 이 방법을 토대로 하여 지오그리드-혼합토 사이의 마찰강도 평가시 적용가능한 보정계수 a1 및 a2 값의 범위를 제시하였다.

• Asia pacific journal of information systems
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• 제12권1호
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• pp.139-158
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• 2002

As the telecommunication market becomes mature in Korea, severe competition has already begun on the market. While service providers struggled for the last couple of years to acquire as many new customers as possible, nowadays they are making more efforts on retaining the current customers. The churn management by analyzing customers' demographic and transactional data becomes one of the key customer retention strategies which most companies pursue. However, the customer data analysis has still remained at the basic level in the industry, even though it has considerable potential as a tool for understanding customer behavior. This paper develops several churn prediction models using data mining techniques such as logistic regression, decision trees, and neural networks. For model-building, real data were used which were collected from one of the major telecommunication companies in Korea. This paper explores various ways of comparing model performance, while the hit ratio was mainly focused in the previous research. The comparison criteria used in this study include gain ratio, Kolmogorov-Smirnov statistics, distribution of the predicted values, and explanation ability. This paper also suggest some guidance for model selection in applying data mining techniques.

• 산경연구논집
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• 제14권5호
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• pp.11-18
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• 2023

Purpose: The current research based on the comprehensive literature evaluation aims to gain insight into the factors contributing to an Oriental art gallery's success and the strategies used to advertise and sell these works effectively. Understanding and experience in Oriental art are essential for finding solutions to these issues. Research design, data and methodology: The current research conducted the following stages to conduct a thorough literature analysis on the issues that plague Oriental art gallery practitioners and the methods used to increase sales of this kind of art: Finding Valuable Resources and Subjects, Screening and Selection of Articles, Data Extraction and Analysis, Synthesis of Findings. Results: After reviewing the many aspects that affect the success of a gallery specializing in Oriental art, there were four key approaches that have emerged for boosting sales of this kind of artwork. Based on the findings, these approaches are grounded in four areas: consumer preferences; marketing methods; pricing strategies; and art investments. Conclusions: All in all, the current study finally indicates that practitioners should consider cultural background, age, gender, income, and level of education when developing marketing strategies and selecting artwork to exhibit. Target marketing is an effective method for attracting and retaining customers.

• 대한치과보철학회지
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• 제40권3호
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• pp.246-261
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• 2002

The screw loosening is one of the complications that happen frequently in dental implant prostheses. The purpose of this study was to evaluate the changes of reverse/loosening (opening) torque of the screw according to the surface modifications by sandblasting and 24K gold electroplating as well as to determine the possibility of the clinical use of a washer in dental implant. The reverse torque of 4 experimental conditions(control, sandblasted, use of washers, electroplasted) was measured by digital torque gauge (Model MGT50Z, Mark-10 Corp., 458 West John Street Hicksville, NY 11801 USA). Electronic torque controller (Nobel Biocare DEA 020) was used in fastening the gold screws into abutment replicas. Mixed Linear Model Analysis method was used for statistical analysis. To examine the changes of screw thread surface, microphotographs were taken by Olympus PME-3 metallurgic microscope (Olympus Optical Co. Ltd., Tokyo, Japan). Within the limitations of this study, the following results were drawn: 1. The surface modifications of the gold screws and the use of a washer have significantly affected the reverse torque value compared to the control group (P<0.01). 2. Sandblasting and electroplating treatments demonstrated significantly higher reverse torque value than that of control group. 3. The use of a washer may be one of the useful clinical methods that prevent the screw loosening. However, further studies are necessary for the material selection and design of the washer.

• Journal of Microbiology and Biotechnology
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• 제13권3호
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• pp.437-443
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• 2003

Bioremediation technologies were applied to experimental microcosms, simulating an oil spill in a lower intertidal area. Three treatments (oil only, oil plus nutrients, and oil plus nutrients and microbial inocula) were applied, and each microcosm was repeatedly filled and eluted with seawater every 12 h to simulate tidal cycles. To minimize washing-out of the inoculum by the tidal cycles, microbial cells were primarily immobilized on diatomaceous earth before they were applied to the oiled sand. Oil degradation was monitored by gravimetric measurements, thin layer chromatography/flame ionization detector (TLC/FID) analysis, and gas chromatography (GC) analysis, and the loss of oil content was normalized to sand mass or nor-hopane. When the data were normalized to sand mass, no consistent differences were detected between nutrient-amended and nutrient/inoculum-amended microcosms, although both differed from the oil-only microcosm in respect of oil removal rate by a factor of 4 to 14. However, the data relative to nor-hopane showed a significant treatment difference between the nutrient-amended and nutrient/inoculum-treated microcosms, especially in the early phase of the treatment. The accelerating effect of inoculum treatment has hardly been reported in studies of oil bioremediation in the Tower intertidal area. The inoculum immobilized on diatomaceous earth seemed to be a very effective formulation for retaining microbial cells in association with the sand. Results of this study also suggest that interpretation of the effectiveness of bioremediation could be dependent on the selection of monitoring methods, and consequently the application of various analytical methods in combination could be a solution to overcome the limitations of oil bioremediation monitoring.

• 아동학회지
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• 제3권
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• pp.1-15
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• 1982

I. Objectives This study was done to analyze and evaluate the attitudes of the working mothers toward the care of infants in group settings. II. Method and Procedures 1. Standardized questionnaire were sent out to look into the following: 1) the attitude of working mothers, who have infants below 4 years of age, regarding their job, care-taker and group settings. 2) the status of taking care of their infants 2. Subjects Women teachers of Seoul and Kyung Ki primary school districts, who have infants below age 4. The selection of these subjects were done by random sampling. III. Results 1. Attitudes regarding their jobs: The first reason for retaining their jobs are for financial reasons; whereas, their intents of self-actualization and contributions to society comes next. 2. The Status of Caretakers 60.7% of the care-takers are family-related members, and 38.3% are not. The educational level of caretakers are as follows, with 19.6% of the caretakers without any formal education, 44% with primary education, and 18.7% having high school education. The reasons for the dissatisfaction by the caretakers are low education, a frequent change of caretaker, and an attitude without affection. The cost of child caring is high, the main reason being the heavy expense spent on the caretakers. 3. Attitudes of care in group settings: 85.9% of the subjects responded with positive reactions for the necessity of having group-settings. The reasons given for the importance of having a group setting are early experience, social interaction with peer group and educational functioning, in addition to protective care. They desire for a family-style care which can raise infants under high quality of care.

• Asian-Australasian Journal of Animal Sciences
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• 제31권1호
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• pp.13-18
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• 2018

Objective: Meat quality including muscle color in chickens is an important trait and continuous selective pressures for fast growth and high yield have negatively impacted this trait. This study was conducted to investigate genetic variations responsible for regulating muscle color. Methods: Whole genome re-sequencing analysis using Illumina HiSeq paired end read method was performed with pooled DNA samples isolated from two broiler chicken lines divergently selected for muscle color (high muscle color [HMC] and low muscle color [LMC]) along with their random bred control line (RAN). Sequencing read data was aligned to the chicken reference genome sequence for Red Jungle Fowl (Galgal4) using reference based genome alignment with NGen program of the Lasergene software package. The potential causal single nucleotide polymorphisms (SNPs) showing non-synonymous changes in coding DNA sequence regions were chosen in each line. Bioinformatic analyses to interpret functions of genes retaining SNPs were performed using the ingenuity pathways analysis (IPA). Results: Millions of SNPs were identified and totally 2,884 SNPs (1,307 for HMC and 1,577 for LMC) showing >75% SNP rates could induce non-synonymous mutations in amino acid sequences. Of those, SNPs showing over 10 read depths yielded 15 more reliable SNPs including 1 for HMC and 14 for LMC. The IPA analyses suggested that meat color in chickens appeared to be associated with chromosomal DNA stability, the functions of ubiquitylation (UBC) and quality and quantity of various subtypes of collagens. Conclusion: In this study, various potential genetic markers showing amino acid changes were identified in differential meat color lines, that can be used for further animal selection strategy.

• 한국조경학회지
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• 제29권3호
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• pp.61-69
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• 2001

This paper presents a case of community participatory neighborhood park design. The site, Yangji park, is located in Sandang-dong, Dongjak-gu, Seoul and the area is about 1,870m. Neighborhood park is defined as an outdoor space which is close to people´s home and is considered to be their own, because of the residents´ collective responsibility, family association, and frequent shared use. It is a place for pleasant rest area for community, sharing a sense of nature and retaining a sense of tradition and culture which is disappearing in a city. It is related to the daily life of the people near the site and becomes a place to let the community increase dialogue and understanding between people. On the other hand, participatory design is a design in which people participate in the design process. Thus people can understand the project well, present their opinions better, and reconcile conflicts between the different interests of people. This design applied a community participatory design method to design a neighborhood park. The major strategies for participatory design were ´workshop´, ´card game´, ´walking site´, ´interview´, and ´questionnaire´. Eight workshops were performed for the participation design. The major spaces and facilities elected by participants were the ´main entrance plaza´, ´entrance symbol space´, ´children´s ´playground´, ´multipurpose sport ground´, ´grass land´, ´foot-pressure area´, ´spaces symbolizing a rock mountain and an old well´, ´space for youth´, ´a pavilion´, etc. From this selection, design concept alternatives were generated by participants. The aster plan was developed from these design alternatives with the help of landscape architects. It was revised by ist visits and community discussions. People were also involved in the construction process and left their own works, such as hand prints, on the site. After construction, residents continued to maintain the park by themselves. As a result, It was found that participatory design was very effective for people´s satisfaction and sustainable park management. By involving people more in the process they developed a sense of community, a sense of ownership, and attachment to the place. In conclusion, it is suggested that we need to develop an effective people´s participation method to Korean society.