목적: 시야검사 시 신뢰도 지수에 영향을 미칠 수 있는 여러 요인들을 정상인과 녹내장환자를 대상으로 비교 분석하였다. 방법: 녹내장이 없는 정상(normal subjects)군 158안과 녹내장 판정을 받은 녹내장환자군 64안으로 나눠서 각각 험프리 자동시야검사계(Carl Zeiss Meditec, Dublin, CA, USA)를 이용하여 검사하였다. 낮은 신뢰도의 검사결과는 신뢰지수를 분석하여, 주시상실도 20% 이상, 허위 양성률 33% 이상, 허위 음성률 33% 이상 등 세 가지 조건에 어느 한 가지라도 해당되면 낮은 신뢰도로 정의하였다. 결과: 총 222안의 실험군 중 정상군(158안)에서는 35안(22%)에서 낮은 신뢰도를 보였으며 녹내장 환자군(64안)에서는 16안(25%)에서 낮은 신뢰도를 보였다. 이들을 재검사 하였을 때 정상군의 35안 중 16안(46%)에서 다시 낮은 신뢰도를 보였고, 녹내장 환자군에서는 16안 중 5안(31%)에서 다시 낮은 신뢰도를 보였다. 처음 검사 시 낮은 신뢰도를 보이는 대상이 재검사시 다시 낮은 신뢰도를 보이는 경우를 알아본 결과 정상군에서는 46%, 녹내장 환자군에서는 31%가 다시 낮은 신뢰도를 보였다. 결론: 자동시야검사라 하더라도 검사진행시 반드시 검사자가 옆에서 주의를 관찰하면서 시야검사를 진행하는 것이 필요하다고 사료된다.

The research proposes seven elimination rules of redundant gates and blocks in Fault Tree Analysis (FTA) and Reliability Block Diagram (RBD). The computational complexity of cut sets and path sets is NP-hard. In order to reduce the complexity of Minimal Cut Set (MCS) and Minimal Path Set (MPS), the paper classifies generation algorithms. Moreover, the study develops six implementation steps which reflect structural importance (SI) and reliability importance (RI) from Reliability Centered Maintenance (RCM) that a priority of using the functional logic among components is to reduce (improve) the system unavailability (or availability). The proposed steps include efficient generation of state structure function by Rare Event Enumeration (REA). Effective use of importance measures, such as SI and ill measures, is presented based on the number and the size of MCS and MPS which is generated from the reference[5] of this paper. In addition, numerical examples are presented for practitioners to obtain the comprehensive understanding of six steps that is proposed in this research.

The purpose of this study was to establish the reliability and validity of the passive lumbar extension (PLE) test and prone instability test (PIT). Thirty-three subjects (14 males, 19 females) with lower back pain enrolled in the study and the subjects were divided into 2 groups (positive and negative instability groups) on the basis of radiographies of flexion and extension. Reliability was determined by the kappa coefficient and validity was examined using calculated sensitivity, specificity, and the likelihood ratio. The results showed that the reliability of the PLE test was higher than the PIT (intra-rater reliability: k=.86 and k=.81, interrater reliability: k=.65 and k=.62) and the validity of the PLE test was also higher than the PIT (sensitivity: 91% and 62%, specificity: 95% and 85% positive likelihood ratio: 20.00 and 4.10, negative likelihood ratio: .10 and .45). In conclusion, we think that the PLE test was a more reliable and valid method for lumbar instability than the PIT.

The purpose of this study was to assess the agreement of manual muscle testing (MMT) and test-retest reliability of a hand held dynamometer for the posterior gluteus medius muscle, with and without lumbar stabilization, using a pressure biofeedback unit for patients with low back pain. The pressure biofeedback unit was used to minimize the substitute motion of the lumbopelvic region during hip abduction in patients lying on their side. Fifteen patients with low back pain participated in this study. A tester determined the MMT grades of the posterior gluteus medius with and without the pressure biofeedback unit. Active hip abduction range of motion with an inclinometer and the strength of their posterior gluteus medius using a hand held dynamometer were measured with and without the pressure biofeedback unit in the MMT position. The agreement of the grade of muscle strength in the MMT, and intra-rater reliability of both the active hip abduction range of motion and the strength of posterior gluteus medius were analyzed using the weighted kappa and intraclass correlation coefficient (ICC), respectively. The agreement of MMT with the pressure biofeedback unit (weighted kappa=.92) was higher than the MMT (weighted kappa=.34)(p<.05). The inclinometer with pressure biofeedback unit measurement of the active hip abduction range of motion had an excellent intra-rater reliability (ICC=.90). Also, the hand held dynamometer with pressure biofeedback unit measure of strength of the posterior gluteus medius had a good intra-rater reliability (ICC=.85). Therefore, the test for muscle strength with pressure biofeedback unit will be a reliable method for the determination of the MMT grades or amount of posterior gluteus medius muscle strength and the measurement of the range of motion for hip abduction in patients with low back pain.

The current research identified the impacts of WOM(Word-of-Mouth) regarding dining experience and the factors which were likely to influence them. Specifically, this study is examined from the perspective of WOM recipient`s in on-line settings. For the purpose of this research, online survey was used and a total 203 online questionnaires of respondents who had experienced restaurant reviews and recommendations via internet last 6 month were analyzed. Overall, the results indicated that in aspects of WOM recipients, the impacts of WOM were ``visit intention``, ``re-WOM intention`` and ``source credibility`` affected ``WOM acceptance`` in this process. Additionally, ``online homophily`` and ``message vividness`` had a positive effects(p<0.001) on builiding source credibility. By clarifying the process between on-line WOM of restaurant consumers and their actual visit, this study intend to provide basis which can be used for restaurant industry`s effective marketing activity.

Visibility of the flow of goods is an important service element when considering how to improve the quality of a logistics service. Registered mail service of Korea Post, one of logistics service providers, currently supply information on the handling of

본 연구는 국내 콘크리트교량설계기준에 신뢰도기반 저항계수를 적용하기 위한 기초 연구로, 구조물의 설계강도를 산정하기 위하여 사용하는 저항계수체계에 따른 설계결과와 신뢰도지수를 비교분석하는 연구를 수행하였다. 현재 국내에서 적용하는 단면저항계수 및 유럽에서 사용하는 재료저항계수를 적용하여 콘크리트 빔 교량들에 대하여 동일한 설계를 수행한 결과를 비교분석하였다. 콘크리트 구조의 강도를 산정하는데 관련된 재료, 치수 및 해석의 불확실성을 고려하여 설계의 안전율인 신뢰도지수를 산정하고, 신뢰도지수에 큰 영향을 미치는 설계변수에 대한 민감도 분석을 수행하였다. 휨강도와 전단강도에 대하여 설계를 수행하였으며, 현행 국내 도로교설계기준, 미국 AASHTO LRFD, 유럽 Eurocode의 저항계수를 적용한 결과 국내 기준의 저항계수에 따른 설계의 신뢰도지수가 가장 컸으며, 활하중의 통계분포 형식에 따라 신뢰도지수에 차이가 있음을 보였다. 콘크리트 보의 휨과 전단에 대한 신뢰도지수에 미치는 영향은 철근의 항복강도와 활하중이 가장 큼을 민감도 분석결과를 통하여 알 수 있었다.

In this study, a reliability analysis method is discussed for the evaluation of the withdrawal ratio of non-repairable items to the normally working items of a controller product model. Although the analysis method is rather straightforward, one can estimate the probability of withdrawal and present the management a useful information on the appropriateness of the warranty period, exploiting the collected data, which is commonplace in the industrial site. For the methodology is to be refined, more systematic collection of data and adoption of more sophisticated analysis method are yet to be desired.

We suggested specific and practical marketing strategies to coffee shop managers and customers to create a symbiotic relationship. The coffee shop's relationship to reliability, commitment, and shop loyalty was analyzed thoroughly. The samples for this study were 393 coffee shop customers in Seoul. The results showed that customer reliability about coffee shops improved as reputation, customer orientation, specialty, and tie increased, but reliability was reduced as the size of the coffee shop became larger. Communication did not significantly affect reliability. Second, customer reliability positively affected commitment, so commitment increased as customer reliability increased. Third, customer reliability positively affected shop loyalty, so shop loyalty increased as customer reliability increased. Fourth, customer commitment positively affected shop loyalty, so shop loyalty increased as customer commitment increased.

The study interprets each of three classification models based on Bath-Tub Failure Rate (BTFR), Extreme Value Distribution (EVD) and Conjugate Bayesian Distribution (CBD). The classification model based on BTFR is analyzed by three failure patterns of decreasing, constant, or increasing which utilize systematic management strategies for reliability of time. Distribution model based on BTFR is identified using individual factors for each of three corresponding cases. First, in case of using shape parameter, the distribution based on BTFR is analyzed with a factor of component or part number. In case of using scale parameter, the distribution model based on BTFR is analyzed with a factor of time precision. Meanwhile, in case of using location parameter, the distribution model based on BTFR is analyzed with a factor of guarantee time. The classification model based on EVD is assorted into long-tailed distribution, medium-tailed distribution, and short-tailed distribution by the length of right-tail in distribution, and depended on asymptotic reliability property which signifies skewness and kurtosis of distribution curve. Furthermore, the classification model based on CBD is relied upon conjugate distribution relations between prior function, likelihood function and posterior function for dimension reduction and easy tractability under the occasion of Bayesian posterior updating.

After stroke, many people have problems with balance during movement. Balance is essential for the optimal functioning of the locomotor system and the performance of many activities of daily living. The Functional Gait Assessment (FGA) is a clinical tool for evaluating balance ability during walking. The test consists of ten tasks, seven tasks of the Dynamic Gait Index and three additional tasks. The purpose of this study was to evaluate the reliability and internal consistency of data obtained with the Korean version of the FGA when used with people after suffering a stroke. One-hundred participants, at least three months poststroke and able to walk at least six meters with or without a walking aid, participated in the study (age range=30~83 years; ). Two physical therapists and two physical therapy students rated the FGA. Intrarater and interrater reliability of the FGA were assessed using kappa statistic and intraclass correlation coefficients (2,1). The internal consistency of the FGA was assessed using the Cronbach alpha. The Cronbach alpha was good (=.86~.93). The intrarater (intraclass correlation coefficient=.92~.95) and interrater reliability (intraclass correlation coefficient=.91, .95) of the total scores administered by the therapists and students were good, whereas the reliability for single item scores when administered by the physical therapists was moderate to good (kapa value=.42~.97). This study found that intrarater and interrater reliability for total FGA scores and internal consistency were good. Therefore, the Korean version of the FGA can be used as a reliable tool to assess the functional gait performance of patients after stroke.

The purpose of this study was to investigate intra-rater reliability and determine the validity of electromyography (EMG) measurements to represent muscle activity and ultrasonography (US) to represent muscle thickness during manual muscle testing (MMT) to external abdominal oblique (EO) and lumbar multifidus (MF). Twenty healthy subjects were recruited for this study and asked to perform MMT at differing levels. The subjects' muscle activity using EMG was measured by a ratio to maximum voluntary contraction (MVC) and root mean square (RMS) methods. The subjects' muscle thickness using US was measured by raw muscle thickness and change ratio of thickness to maximum (MVC) or resting condition. In three trials, measurements were performed on each subject by one examiner. The intra-rater reliability of measurements of EMG and US to EO and MF was calculated using intra-class coefficients. The intra-rater reliability of all measurements was excellent (ICC=.75~.98) in EMG and US. The conduct validity was calculated by one-way ANOVA with repeated measurements to compare whether the EMG and US measurements were different between MMT at different levels. There was only a significant difference between all grades at %MVC thickness measurement of US. These results suggest that a %MVC thickness measurement of US was a more sensitive and discriminate in all manual muscle testing grades. This information will be useful for the selection of US measurement and analysis methods in clinics.