• Title/Summary/Keyword: adjusting coefficient

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Vehicle Behavior Characteristics According to the Change of Vehicle Speed and Road Vertical Grades (차량속도와 도로의 종단경사 변화에 따른 차량거동 특성)

  • Park, Hyeong-Seon;Yoon, Jun-Kyu;Lim, Jong-Han
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.14 no.4
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    • pp.165-172
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    • 2014
  • When a vehicle is running on the road, the surface conditions and environment of road by reason of insufficient road design standards is so greatly that have an effect on drivers. In particular, the road design of the past is conducted empirical and ideal judgment, but recently, the new technical development is attempted that three and four dimensional parameters is reconsidering and adjusting at the same time. In this study, we analyzed the vehicle behavior characteristics according to the change of driving speed and vertical grades on braking at the peak point of the frozen road by using a PC-crash program for traffic accident reconstruction. As a result, we were conformed the fact that the friction coefficient of road surface and the vehicle speed is affected by vehicle behavior characteristics for intersection vertical grades and were showed the feasibility of verification through a simulation in order to solve the problem of road design in advance.

Characterizing Social Welfare Index between Urban and Rural Regions in China: An Application of Principal Component Analysis (중국의 도농 간 사회후생지표 특성에 관한 연구: 주성분분석에 의한 접근)

  • Rhee, Hyun-Jae
    • The Journal of the Korea Contents Association
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    • v.17 no.7
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    • pp.371-383
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    • 2017
  • The aim of this paper is to investigate adjusting process of trade-off relationship between economic growth and income distribution in China which is established by mixed with social and market-oriented economic systems. The characteristic nature of social welfare index in urban and rural regions in China is examined by employing principal component analysis. Empirical evidences reveal that unlike national wide or urban region, the increases of income contribute to improve social well-being in rural region, but not social welfare index. Accordingly, it can be said that although social well-being in rural region seems to be harmful because of weakly organized social welfare index, the potentiality exists to improve social well-being by increased income. Taken all together, the results signifies that the mixed economic system such as China might distribute its increased income appropriately, however, the distributional system is hardly operated to improve social welfare index. And thus the distributional system has to be amended to enhance social well-being in China.

A Study on Rolling Friction Characteristics of Magneto-Rheological Elastomer under Magnetic Fields (자기장 영향에 따른 자기유변탄성체의 구름 마찰 특성 연구)

  • Lian, Chenglong;Lee, Kwang-Hee;Kim, Cheol-Hyun;Lee, Chul-Hee
    • Tribology and Lubricants
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    • v.30 no.4
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    • pp.234-239
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    • 2014
  • Magneto-rheological elastomer (MR elastomer) is a smart material, because it has mechanical properties that change under a magnetic field. An MR elastomer changes its stiffness characteristics when the inner particles (iron particles) align along the direction of a magnetic field. There has been much research to make use of this characteristic to control vibration issues in various mechanical systems, such as for mounting systems in the automotive field, home appliances, etc. Furthermore, the friction and wear properties of MR elastomer have been studied, as these relate to the durability of the material needed to meet engineering requirements. Rolling friction (or rolling resistance) is one of these friction properties, but has not yet been studied in the context of MR elastomers. In this study, an MR elastomer is fabricated in the shape of a hollow cylinder to evaluate the rolling friction characteristic under a magnetic field. The test apparatus is setup and a strain gauge is used to calculate the rolling resistance under test conditions. Permanent magnets are used to supply the magnetic field during tests. The load and rolling speed conditions are also considered for the tests. The test results show that rolling friction characteristic has a different trend under different magnetic field, load, and rolling speed conditions. It is assumed that the stiffness change of an MR elastomer under a magnetic field has an effect on the rolling friction characteristic of the MR elastomer. For the future work, the rolling friction characteristics of MR elastomers will be controlled by adjusting the strength of the magnetic field using electromagnets.

A Noisy-Robust Approach for Facial Expression Recognition

  • Tong, Ying;Shen, Yuehong;Gao, Bin;Sun, Fenggang;Chen, Rui;Xu, Yefeng
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.11 no.4
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    • pp.2124-2148
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    • 2017
  • Accurate facial expression recognition (FER) requires reliable signal filtering and the effective feature extraction. Considering these requirements, this paper presents a novel approach for FER which is robust to noise. The main contributions of this work are: First, to preserve texture details in facial expression images and remove image noise, we improved the anisotropic diffusion filter by adjusting the diffusion coefficient according to two factors, namely, the gray value difference between the object and the background and the gradient magnitude of object. The improved filter can effectively distinguish facial muscle deformation and facial noise in face images. Second, to further improve robustness, we propose a new feature descriptor based on a combination of the Histogram of Oriented Gradients with the Canny operator (Canny-HOG) which can represent the precise deformation of eyes, eyebrows and lips for FER. Third, Canny-HOG's block and cell sizes are adjusted to reduce feature dimensionality and make the classifier less prone to overfitting. Our method was tested on images from the JAFFE and CK databases. Experimental results in L-O-Sam-O and L-O-Sub-O modes demonstrated the effectiveness of the proposed method. Meanwhile, the recognition rate of this method is not significantly affected in the presence of Gaussian noise and salt-and-pepper noise conditions.

Testing the Validity and Reliability of the Korean Version of the Premenstrual Coping Measure among Young Adult Women (성인초기 여성의 한국어판 월경전증후군 대처 측정도구의 타당도와 신뢰도 검증)

  • Kim, Ahrin;Chae, Myung-Ock;Jeon, Hae Ok
    • Journal of Korean Public Health Nursing
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    • v.31 no.2
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    • pp.296-310
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    • 2017
  • Purpose: The aim of this study was to develop and test the validity and reliability of the Korean version of the Pre-Menstrual Coping Measure (PMCM-K). Methods: Translation of the PMCM-K was validated using forward-backward translation methods. The study was conducted as a cross-sectional survey from March 7 to April 30, 2016 and the data from a total of 362 young adult women were used for the final analysis. The content validity, construct validity and criterion-related validity were evaluated. The internal consistency was calculated to assess the reliability. Results: The PMCM-K consisted of five factors: premenstrual coping regarding avoiding harm, awareness and acceptance of premenstrual change, self-care, communicating, and adjusting energy, which all explained 62.0% of the total variance in PMCM-K. The total score of the PMCM-K showed a positive correlation with the shortened premenstrual assessment form (r=.50). The Cronbach's alpha reliability coefficient was .94 for the overall instrument and .77-.93 for five factors. Conclusion: PMCM-K provides a valid and reliable scale for quantifying the ways of coping specific to a negative premenstrual change for Korean young adult women. The PMCM-K will play an important role as a way to gain a sense of agency in coping with premenstrual changes.

Passive Temperature Compensation for All Optical Fiber Type DWDM Interleaver (고밀도 파장분할용 전광섬유형 인터리버의 수동 온도보상)

  • Chang Jin Hyeon;Kim Yung Kwon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.12
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    • pp.35-42
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    • 2004
  • In this paper, we report Mach Zehnder Interleaver of optical fiber type is fabricated by the fabrication system only for interfermeter design, and it is used $CO_2$ laser to adjust precisely the wavelength. The optical fiber is very sensitive in the thermal variation around. Thus, When fabrication the prototype, it is applied a technique to compensate the optical thermal effect because the center wavelength at the output is shifted according to the thermal variation around. it can he done by applying a substrate with high thermal expansion coefficient as well as an adjusting the position between two optical fiber couplers. Consequently, the output wavelength is shifted within 0.05 nm when the surrounding temperature varies until $60^{\circ}C$.

A Study on the Improvement of FEM model in Plate Vibration by Modification of Young's Modulus and Shape (FEM 모델의 형상과 감쇠계수의 추정을 통한 평판진동해석의 개선에 대한 연구)

  • Park, Sok-Chu;Oh, Chang-Guen
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.6
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    • pp.794-801
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    • 2012
  • Finite Element Method is a strong tool to analyse static and dynamic problem of a structure. FEM is a good method for static problem, but for dynamic problem there are some differences between real phenomena and analyzed phenomena. Therefore some modifications are needed to identify two results. In this paper authors propose a genetic algorithm method 1) to adjust dimensions of plate for identifying natural frequencies, 2) to fit amplitude of FEM Frequency Response Function(FRF) onto it of real FRF. Analysis by raw FEM data gave questions if the results were for the same object. By only adjusting Young's modulus much better accordances were obtained, but limitation existed still. Very good agreements were achieved by shape modification and damping coefficient identification.

A Case Study on the Development of an urinary incontinence-preventive equipment (요실금 예방 치료기 제품 개발 사례 연구)

  • Park, Roh Gook
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.7 no.4
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    • pp.143-148
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    • 2012
  • The problem of common difficulties for the implemented business that imposing the Value Engineering(VE) is crucial. Because of the difference in effect of VE by how an abstract concept as function digitize. Furthermore, to improve achievement of VE,, the advancement of VE is demanded. The most of business conducting the VE is pushing this method with the purpose of cost reduction. As explaining this product, the cost occupies the desktop of F1 and the component of product 54% with the result of analyzing the coefficient of functional requirement. Then the functional cost can be confirmed. Through the result of this study, the fact that the desktop, the bluetooth, the probe occupy the most of products with satisfying the function is able to confirm. An effort for cost reduction in purchasing through adjusting a stable quality demanded for the cost reduction is needed. Also, another effort of proper price reduction by diversification of buyer business is needed also.

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The estimation of thermal diffusivity using NPE method (비선형 매개변수 추정법을 이용한 열확산계수의 측정)

  • 임동주;배신철
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.14 no.6
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    • pp.1679-1688
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    • 1990
  • The method of nonlinear parameter estimation(NPE), which is a statistical and an inverse method, is used to estimate the thermal diffusivity of the porous insulation material. In order to apply the NPE method for measuring the thermal diffusivity, and algorithm for programing suitable to IBM personal computer is established, and is studied the statistical treatment of experimental data and theory of estimation. The experimental data obtained by discrete measurement using a constant heat flux technique are used to find the boundary conditions, initial conditions, and the thermal diffusivity, and then the final values are compared with the values obtained by some different methods. The results are presented as follows:(1) NPE method is used to establish the estimation of the thermal diffusivity and compared results with experimental output shows, that this method can be applicable to define the thermal diffusivity without considering hear flux types. (2) Because of all of the temperatures obtained by the discrete measurement on each steps of time are used to estimate the thermal diffusivity. Although some error in the temperature measurements of temperature are included in estimating process, its influences on the final value are minimzed in NPE method. (3) NPE method can reduce the experimental time including the time of data collecting in a few minutes and can take smaller specimen compared with steady state method. If the tube-type furnace is used, also the adjusting time of surrounding temperature can be reduced.

Properties $(Bi,Sb)_2(Te,Se)_3$-based Thermoelectrics Prepared by the Extrusion-Sintering Process (압출-소결법으로 제조된 $(Bi,Sb)_2(Te,Se)_3$계 열전재료의 특성)

  • Ji, Cheol-Won;Kim, Il-Ho;Lee, Dong-Hui
    • Korean Journal of Materials Research
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    • v.9 no.5
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    • pp.520-527
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    • 1999
  • As a new approache(extrusion-sintering process) to fabricate the thermoelectric materials, it has been at tempted to extrude and sinter the powders simultaneously. It was possible to produce the highly dense <$(Bi,Sb)_2(Te,Se)_3$-based thermoelectrics with sound surface appearances and microstructures by adjusting the process variables. For the p-type materials, the Seeback coefficient was increased with the amount of Te dopants, and the thermoelectric figure of merit appeared to be $2.5\times10^{-3}/K$ at room temperature when doped with 3 at % Te. The n-type specimen doped with 0.16 mol% $SbI_3$ showed the thermoelectric figure of merit of $1.8\times10^{-3}/K$. In both p-type an 우-type materials, the carrier mobility an the thermoelectric figure of merit parallel to the extrusion direction were higher than those perpendicular to it.

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