• International Journal of Fuzzy Logic and Intelligent Systems
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• 제9권4호
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• pp.269-274
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• 2009

Measuring uncertainty for fuzzy sets has been carried out by calculating fuzzy entropy. Fuzzy entropy of fuzzy set is derived with the help of distance measure. The distance proportional value between the fuzzy set and the corresponding crisp set is designed as the fuzzy entropy. The usefulness is verified by proving the proposed entropy. Generally, fuzzy entropy contains the complementary characteristics that the fuzzy entropies of fuzzy set and complementary fuzzy set have the same entropies. Discrepancy that low fuzzy entropy did not guarantee the data certainty was overcome by modifying fuzzy entropy formulation. Obtained fuzzy entropy is analyzed and discussed through simple example.

• 한방재활의학과학회지
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• 제20권4호
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• pp.171-183
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• 2010

Objectives : The biomechanical relationship of leg length discrepancy(LLD), Lumbar lordosis, pelvic variance and degenerative scoliosis is one of the most important parameters when treat musculoskeletal disorders, however the reports are still controversial. The purpose of this study was to compare the relationships between the parameters and bothersomeness in subject with chronic ow back pain. Methods : Sixty female and eight male adults with non specific low back pain over 3 months were recruited. LLD was measured by tape measure method. Lumbar lordosis, lumbosacral angle and related pelvic parameters were measured using simple radiologic films of lumbosacral view. Results : Lumbar lordosis was significantly correlated to the lumbosacral angle, pelvic incidence and difference of the both iliac widths. Pelvic incidence had significant correlation with difference of the both iliac widths. And difference of both iliac widths was related with LLD by radiologic film. There was also significant correlation between the LLD by radiologic film and tape measurement. Visual analogue scale(chronic low back pain) of normal lordosis group was greater than hyperlordosis group. Conclusions : There were close biomechanical relationships between lumbar, pelvis, and lower extremity. But in order to determine the effect of structure on the chronic low back pain, global balance of musculoskeletal structure seems to be worth further researching.

• The Journal of Asian Finance, Economics and Business
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• 제8권2호
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• pp.675-684
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• 2021

This paper aims to analyze factors influencing earnings of workers in Vietnam using provincial-level data from 2016 to 2018. We show the important determinants of earnings of workers of more than 15 years old including working hour, labor force, life expectancy, education, regulation measured by Provincial Competitiveness Index (PCI) and especially Industry 4.0, our major depart from literature proxies by government expenditure on science and technology, number of phone lines, and number of internet users. Working hours are a typical measurement of quantity of labor supplied. Labor force represents market size from the supply side. Life expectancy measures the health of laborers, a physical quality measure of workers. PCI stands for institutional status of the locality. Two most important factors of our interest are education, representing qualification of workers, and Industry 4.0, reflecting the new working environment of workers. By estimating a robust standard error fixed-effect model, we have evidence that all factors are significant in explaining earnings of Vietnamese workers. Education and IR4.0 play an important role in earnings of workers of Vietnam. Results also provide an estimation of Vietnam's labor supply in the context of Industry 4.0. In addition, findings contribute to explain the income discrepancy among Vietnamese provinces.

• 한국인터넷방송통신학회논문지
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• 제10권6호
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• pp.215-223
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• 2010

새로운 정보기술의 발전으로 인해 정보 접근과 획득 방식이 훨씬 다양하고 용이해지고 있는 반면 다양하고 성능 좋은 도구를 이용한 불법적인 접근이 가능하도록 하는 부작용이 초래되고 있다. 이러한 위협에 대응하는 데이터베이스 기술로는 접근제어가 있고 현재 새로운 컴퓨팅 환경에 대응하기 위해 전통적인 접근제어를 확장한 다양한 연구들이 수행되고 있다. 본 연구에서는 상황정보의 시멘틱 정보를 기반으로 보안정책에 의해 명시된 상황제약조건이 질의에 수반되는 상황제약조건의 구문과 일치하지 않는 경우에도 적절한 보안정책 집행이 가능하도록 하는 접근제어 방식을 제안한다. 상황에 대한 의미적 정책집행을 위해 시멘틱 트리계층구조 상에서 이들 간의 의미적 함의관계를 이용하고 함의관계에 의해 초래될 수 있는 과도한 권한부여를 방지하기 위해 의미 차를 정량적으로 측정할 수 있는 인수를 정의하여 설정된 시스템 정의 임계치 범위 내에서만 의미적 함의에 의한 권한부여가 이루어지도록 한다.

• 한국안전학회지
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• 제31권4호
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• pp.120-125
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• 2016

Usually, a risk can be expressed as a product of likelihood and consequence of a hazard factor. Therefore, conventional risk assessment is carried out by frequency analysis and severity analysis, in turns. However, it is well known that intuitive thinking is another excellent way of thinking of human beings. This study aimed to confirm whether there exist any difference in risk assessment results derived by two different procedures - intuitive and analytical. Thus, the present study showed 10 different illustrations to 30 undergraduate students. Their responses were organized as fuzzy membership functions, and summarized as risk assessments, and compared. The results were also verified with the help of statistical hypothesis testing, which showed no significant difference. On the contrary, however, similarity measure used in fuzzy set theory was not credible as anticipated. Many cases failed to satisfy statistical hypothesis even with similarity measure higher than 0.60 so that only a trend could be accepted. In addition, a subject showed a somewhat consistent logical discrepancy in his response, which implied the necessity of sincere analysis in fuzzy formulations.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제11권3호
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• pp.165-170
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• 2011

Due to advances in hardware performance, user-friendly interfaces are becoming one of the major concerns in information systems. Linguistic conversation is a very natural way of human communications. Fuzzy techniques have been employed to liaison the discrepancy between the qualitative linguistic terms and quantitative computerized data. This paper deals with linguistic queries using clustering results on data sets, which are intended to retrieve the close clusters or distant clusters from the clustering results. In order to support such queries, a fuzzy technique-based method is proposed. The method introduces distance membership functions, namely, close and distant membership functions which transform the metric distance between two objects into the degree of closeness or farness, respectively. In order to measure the degree of closeness or farness between two clusters, both cluster closeness measure and cluster farness measure which incorporate distance membership function and cluster memberships are considered. For the flexibility of clustering, fuzzy clusters are assumed to be formed. This allows us to linguistically query close or distant clusters by constructing fuzzy relation based on the measures.

• 대한방사선치료학회지
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• 제11권1호
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• pp.43-48
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• 1999

Purpose : For practical application of the MR image for stereotactic radiosurgery, the target point achieved by acquisition of MR image in a relatively homogeneous phantom has to agree with the actual isocenter of irradiation in real radiosurgery and the amount of distortion of the MR image should be known. Materials and Methods : A dosimetric film with a random target point was inserted into a radish vertically and horizontally on axis Z and they were fixed with a headring. After image acquisition by stereotactic radiosurgery planning system, we achieved stereotactic coordinate of the target point and examined irradiation using the coordinate acquired as isocenter. After the irradiation, the film in the radish was developed and processed and the degree of coincidence between the target point marked on the film and the center of the radiation distribution. In order to measure the degree of distortion of the MR image in a different way, an acryl phantom was made and punctures were made at intervals of 1 cm and a drop of oil was dropped into it. Then, it was inserted into the radish vertically and horizontally on axis Z to acquire the MR image. Each coordinate was achieved and the estimation of distortion of MR image was made both in vertical and horizontal directions Results : The film from the radio was developed and for the one inserted vertically on axis Z, there was a good coincidence in the discrepancy between the target point marked on the film and the center of the radiation distribution. For the one inserted horizontally, the discrepancy between them was under 0.5 mm. As a result of estimating distortion of MR image using acryl, the discrepancy was under 0.45 mm in the case of the phantom inserted vertically on axis Z, and that of the one inserted horizontally was 1.4 mm. Conclusion : We were able to confirm good coincidence in homogeneous phantom in actual treatment position of radiosurgery using the MR image and the discrepancy measured in the analysis of distortion of the MR image did not exceed the permissible level. Therefore, it was evident the system of the hospital is suitable for radiosurgery using MR image.

• 한국정밀공학회지
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• 제33권4호
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• pp.295-301
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• 2016

The out-of-squareness is one of the error sources that affect the positioning accuracy of machine tools and coordinate measuring machines. Laser interferometer is widely used to measure the position and angular errors, and can measure the squareness using an optical square. However, the squareness measurement using the laser interferometer is difficult, as compared to other errors due to complicated optics setup and Abbe's error occurrence. The effect of out-of-squareness mainly appears at the face-diagonal of the movable plane. The diagonal displacements are also affected by the position dependent geometric errors. In this study, the squareness estimation techniques via diagonal displacement measurement using the laser interferometer without an optical square were proposed. For accurate estimation and measurement time reduction, the errors selected from proposed discriminant were measured. Discrepancy between the proposed technique with the laser interferometer (with an optical square) result was $0.6{\mu}rad$.

• International Journal of Air-Conditioning and Refrigeration
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• 제11권1호
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• pp.32-39
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• 2003

Though conventional calorimetry methods such as differential scanning calorimetry and differential thermal analysis are used generally in measuring heat of fusion, T-history method has advantages of a simple experimental apparatus and no requirements of sampling process, which is particularly useful for measuring thermophyical properties of in-homogeneous phase change materials in sealed tubes. However, the degree of supercooling used in selecting a range of latent heat release and neglecting sensible heat during the phase change process can cause significant errors in determining the heat of fusion. In the present study, it was shown that a 40% discrepancy exists between the original T-history and the present methods when analyzing the same experimental data. As a result, a reasonable modification to the original T-history method is proposed.

• 한국연소학회지
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• 제20권4호
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• pp.42-48
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• 2015

This study was investigated the estimation of VOCs (Volatile Organic Compounds) emission from a gas station tank. To improve the atmosphere environmental quality near the gas station, the installation of vapor recovery system has been expanded recently. Therefore, it was necessary to calculate VOCs emissions from the gas station tank with vapor recovery systems for evaluation of their performance. The VOCs emissions are difficult to measure directly because of various sources and irregularly emission by pressure rise. In this study, VOCs emissions were estimated by simple calculation based on the equation of state for measured pressure, temperature and volume of a gasoline tank at a gas station. The result confirmed that the present national emission factor did not have significant discrepancy with the calculated value.