• 수면정신생리
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• 제6권2호
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• pp.143-148
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• 1999

목 적: 지각 장애가 어떤 뇌의 부위와 기능에 장애가 있을 때 발생되는지를 알아보기 위해 정신과와 뇌손상 환자에서 신경심리 검사와 지각 장애와 관계성을 조사하였다. 방 법: 정신과 환자 69명, 뇌손상 환자 50명, 총 119명에서 Halstead Reitan 신경 심리 검사와 K-WAIS, MMPI를 시행하였다. MMPI 항목 중 지각 장애와 관계되는 9개 항목에서 산출된 점수와 신경심리 검사의 결과와의 상관 관계를 조사하였다. 또 정신과 환자에서 지각 장애 점수가 높은 지각 장애군 21명과 지각 장애가 없는 지각 장애 17명을 t-test로 비교하였다. 결 과: 뇌손상 환자군에서 지각 장애가 전두엽 기능을 보는 범주화 검사, 선로 잇기 검사, 촉각 수행 검사, 손끝 숫자 쓰기 검사와 우측 반구 기능을 보는 촉각 수행 검사의 위치, 동작성 점수, 빠진곳 찾기, 차례 맞추기, 토막 짜기 등과 유의한 상관 관계를 보였다. 또 피질하 기능을 보는 숫자 상징, 산수, 숫자 외우기와 유의한 상관 관계를 보였다. 정신과 환자의 높은 지각 장애군은 우측 반구 편측화 지수와 빠진 곳 찾기, 토막 짜기와 같은 우측 반구 기능에서 유의한 차이가 있었고, 또 이해, 어휘, 공통성과 같은 좌측 반구 기능에서도 유의한 차이가 있었다. 결 론: 지각 장애는 전두엽, 우측 반구, 피질하 구조의 기능과 깊은 연관성을 가지고 발생이 되며, 정신과 환자군에서는 좌측 반구의 기능도 영향을 주는 것으로 생각된다.

• International Journal of Contents
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• 제16권4호
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• pp.26-38
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• 2020

Determining the optimal levels of the technical attributes (TAs) of a product to achieve a high level of customer satisfaction is the main activity in the planning process for quality function deployment (QFD). In real applications, the number of customer requirements for developing a single product is quite large, and the number of converted TAs is also high so the size of the house of quality (HoQ) becomes huge. Furthermore, the TA levels are often discrete instead of continuous and the product market can be divided into several market segments corresponding to the number of HoQ, which also unacceptably increases the size of the QFD optimization problem and the time spent on making decisions. This paper proposed a genetic algorithm (GA) solution approach to finding the optimum set of TAs in QFD in the above situation. A numerical example is provided for illustrating the proposed approach. To assess the computational performance of the GA, tests were performed on problems of various sizes using a fractional factorial design.

• 오토저널
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• 제3권2호
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• pp.27-33
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• 1981

In the paper, it was attempted to verify how the strength around fillet area of shifted gear would be affected by variables such as number of teeth, shifted value, and diametral pitch. Thereafter, the Lewis' tooth factor of the shifted gear was computed in terms of previously mentioned variables in order to observe the characteristics of stress change related from tooth factor and tooth number with the parameter of shifted values and diametral pitches. From the results of quasi-theoretical values by Finite Element Method(F.E.M.)and experimental values through the photo-elastic tests, the followings were identified. The more the number of gear teeth increased, the more the profile of the tooth became close to that of rack, and accordingly the stresses in the fillet area decreased significantly in certain range. Furthermore, as the shifted value and pressure angle increase the stresses tend decrease. Moreover, the stresses analyzed by F.E.M. in the filled area became around 1.22 times larger than the stresses computed by Lewis' form factor, and this is supposed as on influence of the stress concentration in fillet area.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.995-999
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• 2009

Before a contractor embarks on exporting its services, it needs to know if it is likely to succeed. This research developed two prediction models to help contractors in Singapore predict the number of projects (Y1) and the contract values (Y2) that they are likely to secure from overseas. Detailed characteristics of 60 contractors who export their services (exporters) were obtained from the database of registered contractors in Singapore. Multiple linear regression models were developed and tests showed that Y1 is a robust model. A contractor's chance of winning more overseas projects may be predicted by the number of projects it acted as a subcontractor; the variety of projects it undertakes; the total contract value in the domestic market; and the number of countries it exported its services to. It is recommended that contractors who are planning to export their services be flexible instead of adopt a focused policy of undertaking only one or two project types in a few selected countries.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2011년도 춘계학술대회 논문집
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• pp.105-110
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• 2011

Catwalk structures are temporary walk ways for erection of main cables in suspension bridge. The aerodynamic characteristics of the catwalk structures are not well studied even though the catwalk structures are sensitive to wind action because of its flexibility. Present study demonstrates technical results obtained from wind tunnel tests of various catwalk structures. To obtain the aerostatic force coefficients of the floor system of catwalk, 1/14 and 1/4 scaled partial rigid models were fabricated and tested at the wind tunnel. In order to investigate the Reynolds number effects, the aerostatic force coefficients were measured at various wind velocities ranged from 5m/s to 30m/s. The test results revealed that the Reynolds number effects on aerostatic coefficients were not significant for the catwalk floor systems. An empirical equation for aerostatic force coefficients of catwalk are proposed based on the measured results.

• 한국산업정보학회논문지
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• 제6권1호
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• pp.61-69
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• 2001

본 연구는 관능검사에서 얻은 결과로 평가규칙을 설계하고 이를 이용하여 추후의 관능평가에 응용할 수 있는 방법을 제안함에 있어서, 퍼지추론의 규칙을 효율적으로 설계하는 것에 관련된 것이다. 퍼지추론 규칙의 수는 규칙의 전건부의 구조와 파라미터를 설계함에 있어서 퍼지분할의 수에 따라 결정되는데, 분할의 수가 많다고 해서 최적은 아니므로 효율적으로 규칙의 수를 축소하는 것이 규칙을 응용할 때의 효율성을 제고하는 동시에 실무에 응용할 때 추론엔진의 속도를 높일 수 있다. 이를 위해 본 연구에서는 선행연구에서 제시된 사례를 이용하여 추론규칙의 수를 축소하여도 대등한 결과를 얻을 수 있음을 수치예를 통하여 증명하였다. 본 연구의 결과는 향후 관능검사를 이용하는 다른 분야에도 유효하게 응용될 수 있을 것이다.

• 설비공학논문집
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• 제10권5호
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• pp.509-522
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• 1998

An experimental investigation is reported on the heat transfer coefficient from a rotating flat plate in a round turbulent normally impinging water jet. Tests were conducted over a range of jet flow rates, rotational speeds, jet radial posetions with various combinations of three jet nozzle diameter. Dimensionless correlation of average Nusselt number for laminar and turbulent flow is given in terms of jet and rotational Reynolds numbers, dimensionless jet radial position. We suggested various effective promotion methods according to heat transfer characteristics and aspects. The data presented herein will serve as a first step toward providing the information necessary to optimize in rational manner the cooling requirement of impingement cooled rotating machine components.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2013년도 추계학술대회 논문집
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• pp.268-270
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• 2013

It is well known that tire pattern design factors have a large influence on overall tire performance. In this paper, the basic study on the effects of tire pattern design factors on tire labeling performance has been carried out through experimental tests. The pass-by noise is affected by tire pattern design, by a maximum of 2.7dB(A), and the number of sipes gives large effects on PBN. The rolling resistance is also influenced, mostly by the number of longitudinal grooves and secondly the number of sipes. Finally, there is a weak correlation between PBN and RR when the pattern design factors are changed.

• 한국지반공학회논문집
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• 제33권3호
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• pp.5-15
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• 2017

본 연구는 파주점토에 대해 Casagrande법(동적)과 원추관입시험법(정적)으로 액성한계와 소성한계시험을 실시하여 실험방법과 실험자에 따른 액 소성한계 결정에 미치는 영향을 검토하였다. 총 6명의 실험경험을 가진 학생이 참여하였다. 액성한계시험결과, 원추관입시험법으로 구한 액성한계는 Casagrande법으로 구한 액성한계보다 약 4% 정도 작게 나타났다. 원추관입시험법에서 실험횟수의 증가함에 따라 비례적으로 실험자별 실험값의 차이가 작아지고, 숙련도의 변화 폭도 양호해지는 경향을 보였다. 1점법에서 원추콘관입시험법에 의해 결정된 액성한계 값의 변화는 작고 Casagrande법보다 좀 더 양호한 값을 얻을 수 있었다. 소성한계시험결과, 액성한계와는 다르게 두 시험법의 결과 차이는 없는 것으로 나타났다. 즉, 두 시험방법 모두 실험자별 소성한계는 실험횟수가 증가함에 따라 평균 소성한계 값에 근접해 가는 경향을 보이고 있으며 숙련도의 변화도 실험횟수가 증가 할수록 좋아 지는 경향을 보였다.

• 터널과지하공간
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• 제7권2호
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• pp.108-115
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• 1997

Uniaxial and biaxial compressive tests were conducted on limestone specimens containing artificial joints and a circular hole to investigate the influence of inclination and number of joints on compressive strength and deformation behavior of rock with a circular hole. Under uniaxial and biaxial compressive condition, the inclination of joints showing the maximum and minimum strength were 0$^{\circ}$ and 30$^{\circ}$ respectively, which was independent of the number of joints. Under uniaxial compressive condition, relative maximum strength of rock with n=1 and 3 to intact rock with a circular hole were 12.5%~82.8% and 11.4~62.5% respectively, and under biaxial compressive condition, 18.2~91.0% and 17.0~87.5% respectively. The influence of the number of joints on the decrease of compressive strength was greater under uniaxial than under biaxial compressive condition. Under uniaxial and biaxial compressive condition, axial and lateral deformations of rock showed the least values where $\alpha$=30$^{\circ}$. Under uniaxial compressive condition, axial and lateral deformation at maximum strength of rock have the increasing tendency with increase the number of joints. But they have the decreasing tendency under biaxial compressive condition. Under uniaxial and biaxial compressive conditions, axial deformation of circular hole was greater than lateral deformation without respect to the number of joints and the inclination of joints.