• Journal of the East Asian Society of Dietary Life
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• v.20 no.2
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• pp.328-339
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• 2010

This study was conducted to develop a service quality measurement scale suitable for the fast food restaurant segment. After reviewing the relevant literature, it was decided that the current service quality measurement scales (SERVQUAL, SERVPERF, DINESERV) are not appropriate for the fast food restaurant segment. Based on Cronin & Taylor's (1994) argument, perceived service quality is a form of attitude that represents a long-term overall evaluation of the company. Therefore, this study selected SERVPERF items for the initial pool of service quality items. Through a systematic scale development process, the SERVPERF instrument was then refined and a new concise scale was produced. Specifically, a focus group discussion with a group of patrons who are very familiar with fast food restaurants was conducted and the new service quality measure was refined so that it would be more realistic and closely describe service operation in the fast food industry. Moreover, the data collected from 112 college students who visit fast food restaurants frequently were used to statistically evaluate each of the items again via EFA (Exploratory Factor Analysis) and three sub-dimensions were derived: (1) responsiveness, (2) tangibles, and (3) reliability. Additionally, the data collected from 179 fast food restaurant consumers was used to conduct CFA (Confirmatory Factor Analysis). During this process, the convergent validity, discriminant validity, and internal consistency were double-checked. Overall, the newly developed scale achieved validity and reliability on a theoretical and statistical basis. Possible interpretations and managerial implications are also suggested.

• Journal of Periodontal and Implant Science
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• v.37 no.sup2
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• pp.409-426
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• 2007

세균성 치태는 치은의 염증과 치주 조직 파괴를 동반하는 치주염의 주요한 인자로서 치주 조직 건강을 유지하기 위하여 적절한 치태 조절이 필요하다. 본 논문의 목적은 12주 동안 만성 초기 및 중등도 치주염 환자에서 치은염에 대한 임상 지수의 감소, interleukin-6 (IL-6) 농도와 치주질환 원인균인 Prevotella intermedia (P. intermedia), Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans)에 대한 소니케어 전동 칫솔의 효과를 일반 칫솔과 비교해 보고자 하는 데 있다. 총 82명의 환자를 선택하였으며, 30명은 일반 칫솔, 52명은 소니케어 전동 칫솔 군으로 분류하여 칫솔질 교육을 실시하였다. 전악을 전치부와 구치부로 나누어 초진, 1, 4, 12주에서의 치태, 치은 지수 및 탐침 시 출혈 여부를 조사하였으며, 가장 깊은 치주낭 탐침을 보이는 치아 3개를 선택하여 탐침 깊이와 부착 정도를 측정하였고, 선택된 치아에서 초진, 1, 12주에 채취된 샘플을 통해 치은열구액 내의 IL-6 농도와 P. intermedia, A. actinomycetemcomitans의 CT값을 추가적으로 조사하여 다음과 같은 결과를 얻었다. 1 소니케어 전동 칫솔과 일반 칫솔군 모두 치은 염증을 나타내는 임상 지수 (치태지수, 치은지수, 탐침 시 출혈)는 12주 기간 동안 유의한 감소 (p<0.05)를 보였으나, 전동 칫솔 군에서 통계학적으로 더욱 유의하게 (p<0.05) 나타났다. 2. 전치부를 제외한 구치부 치아에서 소니케어 전동 칫솔군은 12주 기간 동안 탐침 시 출혈의 감소가 통계학적으로 유의하게 (p<0.05) 나타났다. 3. 가장 깊은 치주낭 탐침 깊이를 보이는 3개의 선택된 치아에서 치주낭 탐침 깊이와 부착 정도는 두 군 모두 초진에 비해 유의한 감소 (p<0.05)를 보였다. 퍼센트 변화 비교에서 치주낭 탐침 깊이는 소니케어 전동 칫솔군이 $18.47{\pm}10.05%$, 일반 칫솔군이 $14.19{\pm}8.16%$로, 부착 정도는 소니케어 전동 칫솔군이 $24.26{\pm}12.51%$, 일반 칫솔군이 $15.65{\pm}9.92%$로 각각 나타났으나, 군 간 통계적 유의차는 보이지 않았다. 4. 치은열구액의 IL-6 농도는 두 군 모두 12주 기간 동안 통계적으로 유의한 감소 (p<0.05)를 나타내었다. 퍼센트 변화 비교에서 전동 칫솔군은 51%, 일반 칫솔군은 37%로 각각 나타났으나, 군 간 통계적 유의차는 보이지 않았다. 5. Prevotella intermedia, Actinobacillus actinomycetemcomitans의 관찰에서 두 군 모두 유의한 차이는 없었다. 위 결과를 통해 본 연구에서는 소니케어 전동 칫솔의 사용이 일반 칫솔에 비하여 만성 초기 및 중등도 치주염 환자에서 치태의 제거, 치은 염증 및 임상 지수의 감소에 유의한 효과가 있으며 IL-6의 감소 경향에도 효과가 있음을 관찰하였다.

• 대한공업교육학회지
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• v.33 no.1
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• pp.23-43
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• 2008

The purpose of this study is to provide some necessary baseline data to the information prodigy related research through the study on the brain left/right tendency of information prodigies. Subjects were 298 gifted students(59 information, 79 mathematics, 80 science, 40 invention, 40 social science) and 114 general students summing up 412 in the schools of Daejeon metropolitan area. 'Brain Tendency Test' developed by Torrance and modified by Ko in Korean was used as a tool to measure the prodigies' brain tendencies. Data analysis has been done with the $x^2$ test of frequency with the alpha = .05. The results of this study are as follows. 1) The information gifted students have tendencies of utilizing right brain hemisphere at the most, both left/right brain(whole brain) utilization at the second, and left brain utilization at the last. 2) There was statistically no difference between information prodigies and general students in the left/right brain tendency. 3) There was statistically mild evidence to support the notion that there are some differences in the brain tendency between the group of information prodigies and the group of other area of the prodigies. The degree of inclination to utilize the whole brain hemisphere for the prodigies of the other area was the highest compare to other left/right brain utilization while the information prodigies tend to utilize the right brain hemisphere at the most. 4) The female information prodigies have tendencies of utilizing while brain area at the most, right brain utilization at the second, and left brain utilization at the last contrary to the brain utilization tendencies in the male information prodigies which are the same as the brain utilization tendencies of the information prodigies. However there was no difference in brain tendencies statistically between the two groups since the female subjects were too small.

• The Korean Journal of Nuclear Medicine
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• v.38 no.4
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• pp.300-305
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• 2004

Purpose: We underwent this study to evaluate the factors which influence labeling efficiency when modified in vivo erythrocyte labeling technique was used. Materials and methods: Thirty healthy volunteers (M:F=19:11, age:$25{\pm}2$ yrs) were enrolled in this study. Totally, two hundred ten samples were obtained from them. The 1 mg of stannous pyrophosphate was injected intravenously at the beginning of labeling. After suitable tinning time (5 min, 20 min, 35 min) passed by, blood (5 mL, 3 mL or 1 mL) was withdrawn into 10 mL syringe previously containing Tc-99m (740 MBq) and anticoagulant (heparin, ACD or CPDA) through 19-gauged scalp needle. The generator ingrowth time of Tc-99m was within 24 hrs in each case. The blood samples were placed on rotating invertor during incubation (10 min, 25 min, 40 min) but some of them were not. Immediately after the conclusion of incubation, the labeled blood specimens to analyze were centrifuged. and then %Unbound Tc-99m was calculated. Statical analysis was used paired T-test and one way ANOVA with SPSS 10.0. Results: The binding efficiency at 1 mL of blood volume was $73{\pm}32%,\;91{\pm}10%$ at 3 mL and $96{\pm}7%$ at 5 mL (p<0.01). The binding efficiency at 5 min of tinning time was $45{\pm}23%,\;98{\pm}6%$, at 20 min and $97{\pm}8%$ at 35 min (p<0.001). The binding efficiency at 10 min of incubation time was $96{\pm}7%,\;95{\pm}12%$ at 25 min and $98{\pm}3%$ at 40 min (p>0.05). The binding efficiency in case of using rotating invertor was $96{\pm}7%$ and the binding efficiency in case of not using it was $87{\pm}18%$ (p>0.05). There was no significant difference between them. In binding efficiency according to kinds of anticoagulants, ACD was $98{\pm}4%$, CPDA was $97{\pm}6%$ and heparin was $89{\pm}20%$ (p<0.001). Conclusion: When modified in vivo erythrocyte labeling technique is used with Tc-99m, the methods to obtain the highest labeling efficiency are as follow. The withdrawing blood volume should be over 3 mL, tinning time should be kept between 20 min and 35 min, and incubation time should be kept between 10 min and 40 min. ACD or CPDA have to be used as a anticoagulant except heparin and the blood samples should be placed on rotating invertor during incubation.

• Magazine of the Korea Concrete Institute
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• v.10 no.6
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• pp.149-159
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• 1998

The reasonable prediction of time-dependent deformation of prestressed concrete(PSC) box girder bridges is very important for accurate construction as well as good serviceability. The long-term behavior is mostly influenced by the probabilistic characteristic of creep and shrinkage. This paper presents a method of statistical analysis and sensitivity analysis of creep and shrinkage effects in PSC box been taken into account - model uncertainty, parameter variation and environmental condition. The statistical and sensitivity analyses are performed by using the numerical simulation of Latin Hypercube sampling. For each sample, the time-dependent structural analysis is performed to produce response data, which are then statistically analyzed. The probabilistic prediction of the confidence limits on long-term effects of creep and shrinkage is then expressed. Three measure are examined to quantify the sensitivity of the outputs of each of the input variables. These are rank correlation coefficient(RCC), partical rank correlation coefficient(PRCC) and standardiozed rank regression coefficient(SRRC) computed on the ranks of the observations. Three creep and shrinkage models - i. e., ACI model. CEB-FIP model and the model in Korea Highway Bridge Specification - are studied. The creep model uncertainy factor and the relative humidity appear to be the most dominant factors with regard to the model output uncertainty.

• The Journal of the Korea Contents Association
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• v.18 no.8
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• pp.525-535
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• 2018

If the frequency of a particular class is excessively higher than the frequency of other classes in the classification problem, data imbalance problems occur, which make machine learning distorted. Corporate bankruptcy prediction often suffers from data imbalance problems since the ratio of insolvent companies is generally very low, whereas the ratio of solvent companies is very high. To mitigate these problems, it is required to apply a proper sampling technique. Until now, oversampling techniques which adjust the class distribution of a data set by sampling minor class with replacement have popularly been used. However, they are a risk of overfitting. Under this background, this study proposes ROSE(Random Over Sampling Examples) technique which is proposed by Menardi and Torelli in 2014 for the effective corporate bankruptcy prediction. The ROSE technique creates new learning samples by synthesizing the samples for learning, so it leads to better prediction accuracy of the classifiers while avoiding the risk of overfitting. Specifically, our study proposes to combine the ROSE method with SVM(support vector machine), which is known as the best binary classifier. We applied the proposed method to a real-world bankruptcy prediction case of a Korean major bank, and compared its performance with other sampling techniques. Experimental results showed that ROSE contributed to the improvement of the prediction accuracy of SVM in bankruptcy prediction compared to other techniques, with statistical significance. These results shed a light on the fact that ROSE can be a good alternative for resolving data imbalance problems of the prediction problems in social science area other than bankruptcy prediction.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.1
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• pp.1-17
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• 2001

This research is primarily intended to develop a decision-making support system about the natural environment in the country by integrating various formats of spatial data into a comprehensive GIS database. The first part of the research is to design GIS database as a means of combining thematic cartographic data with field survey records. Ecosystem records acquired by a field sampling have been reproduced as digital thematic maps. The database also included various natural environment related data (map for forestry, soil, national park etc.) collected from many other agencies. The second part of the research is devoted to the design of efficient man-machine interfaces. A key concern in the GUI (graphic user interface) design process was to address the need to handle and to manage large databases by non-GIS experts. The system has been checked experimentally, enabled the users to quarry the data required simply and execute spatial analysis accommodating versatile alternatives in decision-making process. Detailed visual maps can be generated over large areas quickly and easily. The system will serve to increase the scientific and objective decision-making by overcoming serious constraints suffered from the past non-GIS-based approach. It is anticipated that this research output could be used as a valuable reference in building a nationwide natural environment GIS-DB (database) in the central and local governments.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.185-195
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• 2018

As machines have been automated in the field of industries in recent years, it is a paramount importance to manage and maintain the automation machines. When a fault occurs in sensors attached to the machine, the machine may malfunction and further, a huge damage will be caused in the process line. To prevent the situation, the fault of sensors should be monitored, diagnosed and classified in a proper way. In the paper, we propose a sensor fault detection scheme based on SVM and CNN to detect and classify typical sensor errors such as erratic, drift, hard-over, spike, and stuck faults. Time-domain statistical features are utilized for the learning and testing in the proposed scheme, and the genetic algorithm is utilized to select the subset of optimal features. To classify multiple sensor faults, a multi-layer SVM is utilized, and ensemble technique is used for CNN. As a result, the SVM that utilizes a subset of features selected by the genetic algorithm provides better performance than the SVM that utilizes all the features. However, the performance of CNN is superior to that of the SVM.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.3
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• pp.263-273
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• 2008

The precision of sensors' position is particularly important in the application of road extraction or digital map generation. In general, the various ranging solution systems such as GPS, Total Station, and Laser Ranger have been employed for the position of the sensor. Basically, the ranging solution system has problems that the signal may be blocked or degraded by various environmental circumstances and has low temporal resolution. To overcome those limitations a IMU/range integrated system could be introduced. In this paper, after pointing out the limitation of extended Kalman filter which has been used for workhorse in navigation and geodetic community, the two sampling based nonlinear filters which are sigma point Kalman filter using nonlinear transformation and carefully chosen sigma points and particle filter using the non-gaussian assumption are implemented and compared with extended Kalman filter in a simulation test. For the ranging solution system, the GPS and Total station was selected and the three levels of IMUs(IMU400C, HG1700, LN100) are chosen for the simulation. For all ranging solution system and IMUs the sampling based nonlinear filter yield improved position result and it is more noticeable that the superiority of nonlinear filter in low temporal resolution such as 5 sec. Therefore, it is recommended to apply non-linear filter to determine the sensor's position with low degree position sensors.

• Journal of Periodontal and Implant Science
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• v.35 no.3
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• pp.525-536
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• 2005

여러 연구들을 통해 많은 학자들이 임프란트 안정성(stability)은 표면의 특징에 달려있다고 생각하게 되었다. 표면의 구조, 에너지, 산화물(oxide) 두께와 표면성상(topography)등 임프란트의 표면의 특징은 임프란트와 골조직의 반응에서 중요한 역할을 하는 것이 알려짐에 따라 티타뮨 임프란트의 표면의 처리 방법에 큰 관심을 가지게 되었다. 그 중에서 티타늄 임프란트 표면의 산화피막화(anodization)가 한 방법으로 대두되었다. 이 방법은 전기화학적 방식으로 임프란트 표면에 거칠고(rough)두꺼우며(thick), 기공(pore)을 가지는 산화물 막을 형성하는 것으로 산화물의 두께는 coronal 부분(l-2 ${\mu}m$)으로부터 apical부분(7-10 ${\mu}m$)까지 증가하게 된다. 산화피막의 표면에는 다양한 크기의 수많은 기공이 주로 1-2 ${\mu}m$ 두께로 임프란트의 apical 부분에서 존재하며, 임프란트 표면의 거칠기는 conical 위부분에서 apical 부분까지 계속 증가한다(평균 Ra value=1.2 ${\mu}m$). 또 다른 표면 처리 방법으로는 blasting 후에 etching을 한 SLA 표면이 있다. 이 연구의 목적은 일반적으로 많이 이용되고 있는 anodized 표면과 SLA 표면의 조직학적 반응을 비교 분석하는 것이다. 24개 임프란트를(anodized surfaced implant-12개 , SLA-12개, 8mm ${\times}\;{\Phi}$ 4.3) 6마리 토끼의 오른쪽과 왼쪽 femur에 식립하였다. 12주후에 동물들을 희생하여 EXACT cutting-grinding system을 이용하여 샘플을 절단하고 800, 1200 및 4000 번 연마제(abrasive) paper로 20-50 ${\mu}m$ 까지 grinding하였다. 샘플은 Multiple staining 용액으로 염색하여 SLA 임프란트 군과 비교하였다. 골과 임프란트 사이에 연결을 TDI 프로그램을 이용하여 %로 측정하였다. SLA 임프란트 군 경우에는 골과 임프란트 사이의 연결이 $74{\pm}19%$ 이고, 양극 산화한 임프란트 군 경우에는 $77{\pm}9%$이었다. 양극 산화한 티타늄 임프란트의 골 접촉률이 SLA 표면 임프란트 경우과 통계학적으로 유의한 차이는 보이지 않았다.