디스플레이 기술이 다양한 상품으로 점차 발전함에 따라 소비자가 선호하는 디스플레이 유형을 선택할 수 있는 효과적이고 객관적인 비교 평가 방법이 필요하다. 그러나 객관적이고 주관적인 디스플레이 품질 평가 방법은 디스플레이가 상이한 특성을 가지므로 다양한 디스플레이에서 일반적으로 유사하지 않다. 이에, 본 논문은 상대적으로 특성이 서로 다른 디스플레이의 인지 화질 평가를 위해 분석 네트워크 프로세스 (ANP)를 사용하여 이들 디스플레이의 상대적 화질 을 평가할 수 있는 체계적인 시스템을 제안한다. 제안된 평가 방법의 검증은 4 개의 모바일 디스플레이를 사용하여 평가 되었고, 주관적 평가와 제안한 방법의 선호도가 일치함을 보였다.
It has been widely accepted that the pressure management of water distribution systems using pressure reducing valves(PRVs) would be an effective method for controlling leakages. A pressure reducing valve (PRV) regulates outlet pressure regardless of fluctuating flow and varying inlet pressure, thereby reducing leakage and mitigating the stress on the water distribution system. However, the operation of a PRV is vulnerable to its mechanical condition and hydraulic operability. In this research, the effect of PRVs installed in water distribution system are evaluated in terms of hydraulic pressure reduction and mechanical performance by analyzing measured pressure data with statistical approach. A statistical approach using the moving average filter and frequency analysis based on fourier transform is presented to detect abnormally operated PRVs that have been densely installed in water distribution system. The result shows that the proposed approach can be a good performance evaluation method by simply measuring pressures for the PRVs.
For evaluating participation in collaboration project, the peer assement method is mostly used and various scoring methods have been proposed. But, the reliability and validity of the peer assessment method are still doubted for all most method. In order to overcome these weaknesss, some guidelines and training methods have been recommended. In this article, however, statistical technique is proposed for measuring individual contributions to collaboration projects considering each assessor’s reliability. The gist of our proposed algorithm is that an assessor’s reliability depends on the evaluation policy, and this reliability is evaluated by an analysis of variance of the scores assigned by the assessor. We also show that the proposed method is very efficient by case study in university class.
The risk assessment for heavy metal pollutions were analyzed by using statistical techniques including correlation and cluster analyses. The contamination data in this investigation obtained were from the Chungcheongnam-do abandoned mines. The descriptive statistical analysis showed that the values of Pb and Zn were relatively higher than other heavy metal values. The detection of heavy metals by distance from abandoned mines within 1,000m were mostly As, Cd, Pb, and Zn. It was noted, especially, that Zn was even detected at 4,000m The results of coefficient correlation showed that Zn to Cd was the highest values. The cluster and dendogram analyses were generated. The results showed the two clear groups by heavy metal characteristics.
The purpose of this study is to develop a guideline of process capability evaluation and to apply this guideline improving the quality of products, especially in the small and medium enterprises. In this study we deal in the concept of process capability evaluation, the calculation of process capability index, and the application of a case study. Man must compare the state of process with the standards in evaluating of the process capability. Control chart can be used as a yardstick for judgement for the long term period and the distribution shape of histogram for the short term period. Man should regard to the significant figure by the calculation of process capability index.
This study was designed to predict the risk of a hazard chemical, vinyl chloride, by applying dose-response assessment that are one of the major process in practicing risk assessment. After extrapolating from the high dose exposure of vinyl chloride based upon animal carcinogenic data to the low dose exposed to human using several mathematical models, we calculated the cancer potency factors as well as virtually safe dose and the resulted values were compared. This process will provide the new insight to assess the risk of a chemical accurately imposed to human in the future.
In this paper, damage assessment technology based on statistical pattern recognition technology was developed for maintenance of structure and the performance of the developed technology was verified by vibration test. The damage assessment technique uses the improved Mahalanobis distance theory, which is a statistical pattern recognition technique, and developed to take account of the variability between the measured data. In order to verify the damage evaluation performance of the developed technology, a cable damage test was conducted for a cable-stayed bridge. Experimental results show that the developed damage assessment technology has the capability of extracting information that can determine the location of damage due to cable damage.
In this paper, real-time damage assessment technology was developed for detection the damage of bridges in real time and the performance of the developed technology was verified by vibration test. Real-time damage assessment technology was developed by combining statistical pattern recognition technology and simulation technology. In order to verify the developed technology, the earthquake response acquisition experiment was conducted according to the cable damage of the model cable-stayed bridge. As a result, it was confirmed that the developed real-time damage assessment technology can provide information on the location of damaged cable.
우리나라에서는 매년 호우, 태풍, 대설 등 자연재해로 인하여 많은 피해가 발생하고 있다. 자연재해로 인한 피해액과 그에 따른 복구액 역시 점점 증가하고 있는 추세를 보이고 있다. 특히 2011년 서울시 우면산 산사태, 2014년 부산・경남 지방에서의 폭우로 인하여 재산 및 인명피해가 발생하였다. 우리나라의 경우 도시지역에 인구가 집중되는 형태를 띄고 있으며, 이로 인해 도시지역에 재해가 발생하게 되면 치명적인 인명 및 재산피해를 입게 된다. 따라서 도시지역에서는 자연재해에 대한 대응책 마련이 반드시 필요하다. 이를 위해서는 자연재해로 인한 피해를 정략적으로 평가할 수 있어야 한다. 본 연구에서는 자연재해에 대한 인구 통계적 피해를 정량화하기 위하여 인구 통계적 취약성을 평가할 수 있는 지표기반 모형을 서울시에 적용하였다. 해당 모형은 1)연령분포, 2)인구밀도, 3)산업별 종사자 수, 4)외국인 비율, 5)교육수준으로 총 5개의 대리변수로 구성되어 있다. 이를 이용하여 서울시의 25개 자치구와 16,230개의 집계구에 적용하여 인구 통계적 취약성을 살펴보았다. 본 연구를 통해 산정된 취약성 평가 결과는 자연재해에 대한 인명피해를 감소시키기 위한 방재사업을 추진할 때 효과적인 예산분배를 위한 기초자료로 사용될 수 있을 것으로 판단된다.
This paper aims to assess the structural damage caused by fatigue and random impact load using a statistical pattern recognition technology. For experimental studies, a model of cable-stayed bridge was built, and a shaker was to inflict load on the model. Data for damage detection were obtained from the signals of the model on which repetitive load and earthquake load were imposed. Applying the statistical pattern recognition technology which constitutes a control chart by using Mahalanobis distance, a commonly used method for the measurement of statistical distance, we preliminarily assessed structural damage. On the basis of the damage assessment, we developed a Improved Mahalanobis Distance(IMD) to be applicable to a cable-stayed bridge which was damaged by random impact load. Then, we evaluated its performance for the assessment of structural condition. The evaluation showed that the control chart.
For the safety assessment of the existing bridges on the expressway, the statistical properties of the truck traffic on the expressway needs to be investigated. Also, the reduced uncertainties involved in the assessment and the shorter reference period for the assessment are utilized for the modeling of the live load for evaluation of the existing bridges.