• Title/Summary/Keyword: CM method

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Single Crystal Growth of GaAs by Single Temperature Zone horizontal Bridgman(1-T HB) Method (단일 온도대역 수평 Bridgman(1-T HB) 법에 의한 GaAs 단결정 성장)

  • 오명환;주승기
    • Korean Journal of Crystallography
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    • v.7 no.1
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    • pp.73-80
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    • 1996
  • The single crystal growth has been carried out with the newly designed 1-T HB(single temperature zone horizontal Bridgman) system for GaAs crystals of 2 inch diameter doped with Si, Zn or undoped. With this method, incidence probability of single crystallinity was shown to be 0.73. Lattice defects evaluated from EPD(etch pit density) measurement were in the range of 5,000-20,000/cm2, dependent upon the doping condition. For the undoped GaAs crystals, carrier concentrations from the Hall measurement were ∼1×1016/cm3 at the seed part, which were less than half the concentrations of double of triple temperature zone(2-T, 3-T) HB grown crystals. By the 1-T HB method, therefore, GaAs crystals can be grown successfully with better yield and higher purity.

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Prediction of Precipitated Wax Amounts Using FTIR Spectroscopy (FTIR을 이용한 왁스 침전의 정량적 예측)

  • Oh, Kyeongseok
    • Korean Chemical Engineering Research
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    • v.51 no.3
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    • pp.376-381
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    • 2013
  • High molecular weight paraffinic waxes dissolved in oil phases can be precipitated when the surrounding temperature becomes lower than the wax appearance temperature (WAT). While the various methods of WAT determination have been developed, the determination of precipitated wax amount has not been comparably popular at temperatures below the WAT. It is important to predict how much solid wax content precipitates in temperature variance. The study develops the previous method which uses integrated areas determined at a wavenumber range of 735~715 $cm^{-1}$. This method uses two different wavenumber ranges, 735~715 $cm^{-1}$ and 1,402~1,324 $cm^{-1}$. The study shows how the method provides reliable data in the variety of applications regardless of FTIR spectral instability often occurred, such as volume reduction during cooling procedure and existence of emulsified water in oil phase.

Removal of Phenol Loaded with Activated Carbon by Potentiostatic Method (정전위전해에 의한 활성탄에 함유된 페놀 제거)

  • 김성우;박승조
    • Resources Recycling
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    • v.10 no.4
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    • pp.18-23
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    • 2001
  • Air pollutants, phenol was generated in case of thermal regeneration of used activated carbon loaded with phenol and because of this problem, removal process of phenol were studied. Electrolytic oxidation of samples, used S.company granular activated carbon (WS-GAC), used C.company granular activated carbon (WC-GAC) and used L.company granular activated carbon (WL-GAC) loaded with phenol carried out by potentiostatic method in this study. In case of experiment was to come into operation in condition of samples containing 100 mg/g phenol, supporting electrolyte was 1.0% sodium chloride solution, Ti-Ir (10$\times$10$\textrm{cm}^2$) electrode and electrode distance was 2 cm, current density was $1.25 A/dm^2$, Obtained from the results of electrolytic oxidation experiments were not detected residual phenol. And then we knew about reaction time of electrolytic oxidation, current density, concentration of supporting electrolyte and electrode and electrode distance were 60 minutes, 1.25 A/dm$^2$, 1.0%, 2 cm.

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A Study on Classification of Bodytype of Elderly Males for Upper Garments Construction (상의 구성을 위한 노년기 남성의 체형 분류)

  • 이선명
    • The Research Journal of the Costume Culture
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    • v.1 no.2
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    • pp.159-179
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    • 1993
  • The purpose of this study is to collect data for he improvement of the accuracy of upper garments construction of the old whose bodies have been changed due to their age. In this study the body measurements with 61 items were taken from 226 men(aged fro m 60 to 80) living in Seoul by the R. Martin's method in 1992. The data were calculate by computer and analyzed by the multivariate method, especially factor and cluster analysis. The results of the study were as follows; 1. The average stature of elderly males was 163.6cm, chest circumference 91.6cm, waist circumference 9\\85.5cm. hip circumference 92.8cm, neck circumference 37cm, arm length 55.4 cm, back length 42.6cm, shoulder breadth 42.9cm and the Roher's Index 1.39, which was a standard body shape. 2. The items of factor analysis were explained to seven, namely, the degree of fatness of the upper body, the size of the frame of body, the length of the upper body, the degree of curve of the front body, the size of shoulder, the shape of the back, and the slope of shoulder. 3. The body types of subjects were classified into four types. The majority was type 4, which was 67% of subjects and considered as balanced body type. The distinctive features of those types are as follows; Type 1. The subjects of this type had a slight skeletal structure and were the thinnest of all the subjects with thin and forward-bent arm. Type 2. The subjects of this type were the tallest of all the subjects. they had the straightest side of body and a well-developed upper arm. The thigh length of this type was longer than the length of trunk. Type. 3. The subjects of this type was only one, so ti could be excluded. Type 4. The subjects of this type had a long trunk, well-developed shoulder, and a crook in their neck and back. The arm length and thigh of this type were short and those circumferences were thick. Type 5. The subjects of this type were the shortest of all, but had the highest degree of fatness in the waist and abdominal. They had well-developed front muscles of body and projected hip.

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Studies on the Grazing Behavior on Mixture Pasture I. Grazing cattle`s paratabiility through grazing time method in response to differente sward height (혼파초지에서 가축의 방목행동에 관한 연구 I. 채식시간법에 의한 초고별 방목우의 채색기호성)

  • 김성우;전병태;신재순;황석중
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.9 no.2
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    • pp.88-95
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    • 1989
  • This experiment 'was conducted to investigate the grazing cattle's palatability by the method of grazing time on the pasture dominated orchardgrass and on the pasture dominated perennial ryegrass from June to October, 1987. The experiment was carried out on the experimental field at Livestock Ex- Experiment Station. The results are summarized as follows: 1. In summer, the grazing time on the pasture dominated orchardgrass increased in 49.7 min, 57.4 min, 102 min, 118.7 min, respectively as sward height decreased in 50 cm, 45 cm, 35 cm, 23 cm, respectively and their correlation coefficiet was -0.9722*(P <0.05). 2. In autumn, the grazing time on the pasture dominated perennial ryegrass decreased in 182 min, 98.5 min, 49.4 min, 31.9 min, respectively as sward height decreased in 43 cm, 34 cm, 25 cm, 18 cm, respectively and their correlation coefficient was 0.9684*. (P <0.05). 3. Grazing time increased as sward height increased on the pasture dominated perennial ryegrass because the composition rate of orchardgrass and red clover which were palatability on the plot of the high sward height.was many. It was suggested that the factor that could be first related to palatability on mixture pasture was the factor of species than the factor of sward height. 4. When the eating rate on the plot of the low sward height was over 55% as the grazing day went by, it gradually decreased because the eating rate on it was high but the fresh yield was low. After all it seemed that it affected palatability because forage availability on the plot of the low sward height was degenerating.

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Comparative Smoke Analysis of CORESTA Monitoring Cigarettes (CORESTA 모니터링 담배의 비교 분석)

  • Lee, Seung-Yong;Ji, Sang-Un;Shin, Hea-Geun
    • Journal of the Korean Society of Tobacco Science
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    • v.33 no.1
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    • pp.28-38
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    • 2011
  • This experiment was conducted as a part of Asia collaborative study on purpose of verifying the difference between CM6 and CM7 including 3R4F for reference. It carried out using various analytical categories for example, main stream, sidestream and Av. smoke. Additional analysis such as physical properties, blending ratio, combustibility and general leaf component analysis also implemented in order to investigate the difference. We complied with ISO standard and CORESTA recommended method during analytical operating procedures. In this study, we described that comparative analytical result for CM6 and CM7 known as reference or monitoring cigarettes including 3R4F for reference. All sample cigarettes were conditioned at $22^{\circ}C$, 60% relative humidity for 48 hours. Av. Smoke, MS and SS smoke analysis were performed over five times with two smoking condition, ISO and Health Canada with the exception of Av. smoke analysis. We complied with ISO standard method during analytical operating procedures. And, we conducted additional analysis, such as physical properties, blending ratio, combustibility and leaf component analysis also in order to investigate the difference. In conclusion, we found out some differences between CORESTA monitoring cigarette No. 6 and No 7. The smoke components such as total particulate matters, NFDPM, nicotine and carbon monoxide contents of CM7 were a little lower than CM6. And, these phenomena were the same as not only main stream smoke but also side stream smoke and Av. smoke. This tendency was consistent with ISO and Health Canada smoking condition. Besides, leaf constituents' color of CM7 was darker than CM6. In case of combustibility, it showed short combustion time approximately 30 seconds.

The Comparative Consideration of the Dart Design - Centering on Trousers and Skirt - (다아트 구성에 대한 비교고찰 - 하반신 의복을 중심으로 -)

  • Jung Ok Im
    • Journal of the Korean Home Economics Association
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    • v.43 no.5 s.207
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    • pp.117-130
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    • 2005
  • Western clothing is adjusted to the figures of the human body unlike Korean traditional clothes. For this adjustment, we need a method, known as dart, to reasonably adjust a wide circumference to curves of the human body. So far, there has been some research in the aspect of clothing engineering on how to decide darts of skirts or trousers, but no theoretical research has yet been conducted on how to decide the number and amount of dart, which has caused difficulties in beginners' understanding of dart. Futhermore, there is no consistent drawing method for the number and amount of darts in existing teaching and teaming materials. Therefore, to develop teaching and teaming methods for darts, this study identified the amount and number of darts for waist girth of 66-72cm and a hip girth of 86-102cm. When the difference between the waist girth and the hips girth, including margins, is above a minimum of 26cm, two darts can be designed, but when the difference is below 24cm, one dart is necessary. The amount of darts increases by 0.5cm for every 2cm increase of the hip girth to the waist girth. In addition, as darts become longer, the cutting of the waist line becomes smoother. For one, rather than two, darts the curve of the waist line is steeper. Based on the above results, it was assured that when belts are curved through adjustment to the waist line of skirts or slacks, their composition can be stable. Therefore, in basic teaching about slacks and skirts, the number and amount of the darts should be designed according to the difference between the girths of the waist and the hip. This difference should be a minimum of 24cm, but if it is below 24cm, the number of darts needed is one.

Precise Measurement Method and Error Analysis with Roughness Variables for Estimation of Scattering Coefficients (지표면 산란 계수 예측을 위한 정확한 지표면 거칠기 변수 측정 방법 및 오차 분석)

  • Kweon, Soon-Koo;Hwang, Ji-Hwan;Oh, Yisok;Hong, Sungwook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.24 no.1
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    • pp.91-97
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    • 2013
  • The input parameters of scattering models for computing the backscattering coefficients of earth terrains are mainly soil moisture and surface roughness. The backscattering coefficients of soil surfaces are more sensitive to surface roughness than soil moisture. In this study, we propose a precise measurement method for roughness parameters and analyze measurement errors. We measured surface roughness using a pin-board profiler(1 m, 0.5 cm interval) and a laser profiler(1 m, 0.25 cm interval). The measurement differences between two profilers in an average sense are 0.097 cm for root-mean-square (RMS) height and 1.828 cm for correlation length. The analysis of the correlation functions and relative errors shows that the laser measurements are more stable than the pin-board measurements. The differences of the calculated backscattering coefficients using a surface scattering model between pin-board and laser profiler measurements are less than 1 dB.

The Growth Rate of Salix Gracilistyla Miq. and its Effect of Protecting Soil from Dispersion Depending on the Planting Method Applied to Shore-marginal Slope (습지 수제부에서 삽목방법에 따른 갯버들 생장율 및 토양 유실 억제 효과)

  • Lee, Chun-Seok;Ryu, Nam-Hyung
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.6 no.3
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    • pp.56-68
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    • 2003
  • The main purpose of this study was to verify the shore margin protection effect of the root system of Salix gracilistyla Miq. developed from direct sticking cuttings on wetland, through the measurement of root growth and comparison of soil slaking rate depending on the planting method applied to shore-marginal slope. Comparison of growth rate and soil dispersion rate was made between five planted slope and one naked slope. The planting methods applied to the planted slope were (a) horizontally layed burying of stick(45cm) bundle (b) horizontally layed covering the slope with sticks (c) horizontally fencing with normal cuttings(20cm) (d) elected sticking of normal cutting at equal distances (e) random scattering short cuttings(3-4cm). As results, the most effective planting method was horizontally layed burying, and in order to increase its efficiency scattering the live stem chips in 2-3cm on the slope is recommended. The growth of root was negatively regressive to the distance from water floor.

Surgical Margins for Excision of Dermatofibrosarcoma Protuberans (융기성 피부섬유육종의 외과적 절제연)

  • Bae, Yong Chan;Moon, Jae Sul;Nam, Su Bong
    • Archives of Plastic Surgery
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    • v.32 no.4
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    • pp.454-460
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    • 2005
  • Dematofibrosarcoma protuberans(DFSP) is a moderate-degree malignant tumor with high recurrence rate and low metastasis rate, from soft tissue. Principle of treatment is wide excision or Mohs micrographic surgery(MMS). Although wide excision has been performed with surgical margins of 2-5 cm until nowadays, there are problems of preservation of surrounding normal tissue. Therefore the authors tried to identify desirable surgical margins and operative method. From January 1999 to April 2003, 12 patients with DFSP were operated. We applied different surgical margins and operative methods according to the location of lesions. On the face, we performed MMS with surgical margin of 3-4 mm in 2 cases although there are problems of operation time and expense. But on the extremities and trunk, we performed authors' method to begin excising with surgical margins of 1 cm and excise extensively with MMS by 1 cm in 4 cases after April, 2001 although we had performed wide excision with surgical margin of 3 cm in 6 cases before. There was no recurrence or metastasis in the follow-up period. So we think that author's method is effective in surgical excision of DFSP