• Title/Summary/Keyword: Short-cut method

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A Theoretical Study of Photothermal Pulsed Radiometry Method for the Thermal Diffusivity Measurement (재료의 열확산계수 결정을 위한 광열복사법의 이론적 연구)

  • Yook, Hyung-Kyu;Yoo, Jai-Suk;Kim, Hyun-Jung;Lee, Kwang-Jai
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.29 no.1 s.232
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    • pp.27-34
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    • 2005
  • We analyze in detail axially symmetric theoretical study for the photothermal pulsed radiometry of a cylindrical model. The theoretical solutions describe the transient infrared radiation from the sample heated by short-duration pulsed heating. In the conventional transmission radiometry technique, the excitation source and the detector are on opposite sides of the sample, otherwise in the new single ended radiometry technique, the excitation source and the detector are on same sides of the sample. The analytical solution described for photothermal radiometry in this study would not need to cut or polish samples to measure the thermal diffusivity. Therefore the radial area and axial thickness of samples are not limited. The effects of excitation pulse duration and the area of heat source are discussed.

The Rationalization of Distribution Structure in Diamond Market and Study on Diamond Grading System In Korea (다이아몬드의 유통구조와 국내감정 현황에 관한 연구)

  • Lee, Sang-Ki
    • Journal of Distribution Science
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    • v.14 no.4
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    • pp.103-110
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    • 2016
  • Purpose - This study investigates the improvement of rationalization of distribution structure in Korean diamond market. It also explores the international distribution of diamond and how the distribution of Korean diamond market system was improved. This study also for providing the evaluation method in case of purchasing diamond on the consumers. Research Design, Data, and Methodology - The research investigates how international diamond distribution market has been changed since 1933 by De Beers. The international Diamond rough stone has been deregulated in supply and demand by Debeers since July, 2000, therefore, the price maintenance policy of diamond market also has been changed. In the short term, the diamond price in market has been down, whereas, in the long term, the market share of Debeers has affected the high quality of diamond price in world market. Before 1985, both G color and VVS1 clarity were used as the level of percentages in the diamond certificate of authenticity in Korea. But, after 1985, the diamond certificate of authenticity uses Diamond Grading Report. Results - Between the 1970's and 1980's, Debeers had controlled about 80 percentages of international diamond supply market. But, Debeers share in diamond market fell by 60 percentages in 2000's. Debeers supplied 31%(4390 carets) of international diamond supply and 41%(39 billion dollars) in 2003. However, Debeers shares 50% of market shares in the diamond supply market by Alosa in Russia. In Korea, the diamond grading report system has been used since 1985. But, the diamond grading report system has price bubbles and much irrational parts in grading system methods. Conclusions - 4C, the grading system of diamond, is a method for comparing and evaluating diamond objectively. Diamond is graded according to its color, cut, clarity, and carat. The price of diamond is determined based on its each item. Consumers purchase diamond for the purpose of investment and wearing. In terms of investment, it is recommended to purchase diamond with color of D grade, cut with Excellent or Very Good Cut grade, Clarity of FL or IF, and more than 3 carat. As for wearing purpose, it is highly recommended for diamond to have color of F or G grade, cut of Excellent or Very Good Cut, clarity of VS2 or SI1, and more than 1 carat Before 2000, Central Selling Organization(CSO) distributed about 80 percentages rough diamond to world market exclusively by purchase, classification, assessment, and sales. After 2000, Dbeers diamond company looses slowly market shares, while Almosa diamond company etc. in Russia are taking over world market shares more and more. Debeers market shares have been falling over the years, and the international diamond markets are gradually growing by other international diamond companies. But, there is no change in Korean diamond market after 1980's. Korean diamond distribution needs to follow international level of Diamond Grading System. By using different grading systems with different panel members, Korean diamond grading system needs to follow international perfect grading systems to grow diamond markets and maintain within top 10 diamond markets countries.

The Attitude of Hair Cut, Permanent Wave, Coloring by Age in Women's Customer (미용실 여성고객의 연령에 따른 헤어 컷, 퍼머넌트, 염색에 대한 태도)

  • Choi, Soo-Jung;Park, Hye-Won
    • Journal of Fashion Business
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    • v.12 no.4
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    • pp.28-45
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    • 2008
  • The purpose of this study is to diagnose actual condition of preference of hair-styling, hair-styling techniques, management, grasping a consumer's consciousness, etc with women living in a city. The survey was gotten to a feminine customer who visited the ten of beauty-shops in shopping center. And statistical data about the actual condition of hair-styling preference realities, hair-styling method and style management was entered into the SPSS statistics analysis system. In brief, be as follows by the results of study. There showed significant difference that noted in hair-style information and basis alternative a beauty salon, there were able to know people whose age is from 20's to 40's got mainly an influence of public media very much and from 40's to 50's got mainly an influence of people around them. Basis alternative of a beauty salon showed significant difference to follow age categories. It appeared that introducing from people around them have a effect on the 20's and 30's, and 40's got an influence of convenience of traffic, and 50's got mainly the shortest distance. In an attitude toward a hair style, especially toward hair cut, a case to do hair cut was most a lot of in own selections, and its result was independent of age categories. The reason that wants to give a chance was most a lot of thinking without an age. Preference length of hair cut showed a significant difference according to age. In permanent section, own selections appeared most regardless of age. And in the permanent motive, also, to have a change appeared most regardless of age. And people had a preference natural to role up to setting regardless of age in permanent wave. In hair color section, women whose age is 20's, 30's, 40's had a motive for a change, on the other hand, 50's and their senior had a motive for a gray hair. Women of all over the age almost knew a fashion color, and they had a preference brown color. In a preference way along a hair color kind, there was a significant difference according to age, also. 20's and 30's did mainly 'semi-permanent coating' and 40's and 50's did mainly 'permanent hair color'. In a attitude about a hair-style management, the more age is young, the more a period is long term. And the more age is old, the more the outlay for price of cut is expensive. But, on the contrary, permanent price showed that the more age is young, the more the outlay for price of permanent is expensive. In hair color, the more age is old, the more a period is short and the more price is low.

The Mixing Ratio of Wood Waste on Slope Revegetation base Materials (임목폐기물을 활용한 비탈면 녹화용 식생기반재 배합비율)

  • Park, Yeon-Jae;Jeon, Gi-Seong;Cho, Dong-Gil;Shim, Yun-Jin;Do, Jong-Nam;Park, Mi-Young;Lee, Jai-Young
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.19 no.4
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    • pp.45-59
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    • 2016
  • This study introduced wood waste into revegetation base materials for recovery of highway cut slope. The object of this study is to derive the mixing ratio of wood waste, kaoline and silica by conducting a test installation, monitoring, analysis and evaluation. The following items were investigated and analyzed each experimental zone to deduce the mixing ratio of wood waste, kaoline and silica on slope revegetation base materials: the physical and chemical properties of the vegetation base materials, soil-hardness, soil-humidity, collapse and eroded spots, established number of trees, existing species of grass and tree species, vegetation coverage ratio, pest status, and invasion of disturbance species. The revegetation method was evaluated in each experiment zone which had different mixing ratios. As a result, experiment zone C scored 47 points out of 60 as the best revegetation method. However, this result has been derived from just one construction and short-term monitoring. In order to derive the suitable and dependable mixing ratio, conducting an objective revegetation method evaluation and long-term experimenting and monitoring is required.

Development of a New Double Buffer Layer for Cu(In, Ga) $Se_2$ Solar Cells

  • Larina, Liudmila;Kim, Ki-Hwan;Yoon, Kyung-Hoon;Ahn, Byung-Tae
    • 한국신재생에너지학회:학술대회논문집
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    • 2006.06a
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    • pp.152-153
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    • 2006
  • The new approach to buffer layer design for CIGS solar cells that permitted to reduce the buffer absorption losses in the short wavelength range and to overcome the disadvantages inherent to Cd-free CIGS solar cells was proposed. A chemical bath deposition method has been used to produce a high duality buffer layer that comprises thin film of CdS and Zn-based film. The double layer was grown on either ITO or CIGS substrates and its morphological, structural and optical properties were characterized. The Zn-based film was described as the ternary compound $ZnS_x(OH)_y$. The composition of the $ZnS_x(OH)_y$ layer was not uniform throughout its thickness. $ZnS_x(OH)_y$/CdS/substrate region was a highly intermixed region with gradually changing composition. The short wavelength cut-off of double layer was shifted to shorter wavelength (400nm) compared to that (520 nm) for the standard CdS by optimization of the double buffer design. The results show the way to improve the light energy collection efficiency of the nearly cadmium-free CIGS-based solar cells.

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Partial Discharge Location Method using Group Velocity Difference of Modes in a Electromagnetic Partial Discharge Signal in Gas Insulated Bus (가스절연모선(GIB)에서 전자파 방전신호의 모드별 군속도 차이를 이용한 방전위치 산정기법)

  • Goo, Sun-Geun;Ju, Hyoung-Jun;Park, Ki-Jun;Han, Ki-Seon;Yoon, Jin-Yul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.56 no.12
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    • pp.2184-2188
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    • 2007
  • We developed a novel method of partial discharge(PD) location based on the fact that the waveform of PD signal propagate along the GIB (Gas Insulated Bus) is composed of several modes of electromagnetic wave with different group velocities and cut-off frequencies. From the PD waveform, measured at a broadband PD sensor attached on the GIB, we could derive arrival time and frequency components of different modes using the short term Fourier transform or etc. After the group velocities of different modes are calculated, the location of the PD source could be estimated. To show the effectiveness of this new locating method in a real on site application, we used this method to locate the position of a PD source at a 76 m long 345 kV GIB substation. The estimated location of the PD source using the method proposed above was in good agreement with the actual location found from the inspection result of internal component in the GIB with 2.4% of the estimation error.

기계가공면의 소성 스트레인에 관한 연구

  • 김태영;신형곤;소율영
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1991.11a
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    • pp.54-58
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    • 1991
  • It is well known that metal cutting leaves a plastically deformed layer in the machined surface. This residual phenomenon affects in various forms the physical properties of machined components such as the fatigue strength, the dimensional instability, microcracks, and the stress corrosion cracking. These physical properties, so called surface integrity, are very important for designing highly stressed and critically loaded components. Typical plastic strains in the machined surface are very difficult to measure, since they are located within a very short distance from the surface and they change very rapidly. There is an alternative way to determine the residual strain in plastically deformed materials by measuring the grain size after a subsequent recrystallization process. Although, this technique has been successfully applied by several researchers to find the plastic zone around notches and cracks in various materials and welding beads, few works have been reported using the recrystallization method to determine the residual strains in machined surface. Therefore, the purpose of this investigation Is to explore the effectiveness of the recrystallization technique in machining applications, and in particular, to find the effect of cutting parameters, i.e., depth of cut and rake angle on the plastic strains.

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A Leakage Current Supervising Control and Data Acquision in the Building based on Embedded System (임베디드 시스템을 이용한 빌딩 누전감시 시스템)

  • Shin, Seung-Woo;Yu, Jong-Il;Chang, Kyung-Bae;Shim, Il-Joo;Park, Gwi-Tae
    • Proceedings of the KIEE Conference
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    • 2004.07d
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    • pp.2457-2460
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    • 2004
  • As the usage of electron electricity is rapidly increasing, corresponding accidents also take place proportionately. Although various losses occur very often because of senility of system and maintenance, only a earth leakage current breaker by a leakage current alert is used. That means it is always fraught with dander. This paper, we propose to measure and cut a leakage current and method of taking a measurement current short circuit. Besides, through keeping watch communication with server, prevent electric loss and mishap in advance.

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Low-frequency Mosaicism of Trisomy 14, Missed by Array CGH

  • Lee, Cha Gon;Yun, Jun-No;Park, Sang-Jin;Sohn, Young Bae
    • Journal of Genetic Medicine
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    • v.10 no.1
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    • pp.52-56
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    • 2013
  • Mosaic trisomy 14 syndrome is a well-known but unusual chromosomal abnormality with a distinct and recognizable phenotype. Array comparative genomic hybridization (CGH) analysis has recently become a widely used method for detecting DNA copy number changes, in place of traditional karyotype analysis. However, the array CGH shows a limitation for detecting the low-level mosaicism. Here, we report the detailed clinical and cytogenetic findings of patient with low-frequency mosaic trisomy 14, initially considered normal based on usual cut-off levels of array CGH, but confirmed by G-banding karyotyping. Our patient had global developmental delay, short stature, congenital heart disease, craniofacial dysmorphic features, and dark skin patches over her whole body. Estimated mosaicism proportion was 23.3% by G-banding karyotyping and 18.0% by array CGH.

Prediction of Highway Traffic Noise-calculation of Sound Attenuation during Propagation (고속도로 교통소음 예측-전달감쇠 산정)

  • 조대승;김진형;최태묵;오정한;김성훈
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.3
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    • pp.236-242
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    • 2002
  • This paper presents some advanced and supplemental methods to enhance the accuracy In case of calculating geometric divergence attenuation, attenuation by multiple screening structures, ground attenuation at unflat surfaces of sound during propagation outdoors by the methods specified in ISO 9613-2. Moreover, a calculation method for considering short-term wind effect, specified in ASJ Model-1998, is also introduced. To verity the accuracy of adopted methods, we have carried out highway traffic noise prediction and measurement at tile twelve locations appearing representative road shapes and structures, such as flat, retained cut, elevated, barrier-constructed roads. From the results, we have confirmed the predicted results show good correspondence with the measured at direct, diffracted and reflected sound fields within 30 m from the center of near side lane.