• Title/Summary/Keyword: study method

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A Study on Determining Job Sequence by Sampling Method (II) (샘플링 기법에 의한 작업순서의 결정 (II))

  • 강성수;노인규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.12 no.19
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    • pp.25-30
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    • 1989
  • This study is concerned with a job sequencing method using the concept of sampling technique. This sampling technique has never been applied to develop the scheduling algorithms. The most job sequencing algorithms have been developed to determine the best or good solution under the special conditions. Thus, it is not only very difficult, but also taken too much time to develop the appropriate job schedules that satisfy the complex work conditions. The application areas of these algorithms are also very narrow. Under these circumstances it is very desirable to develop a simple job sequencing method which can produce the good solution with the short tine period under any complex work conditions. It is called a sampling job sequencing method in this study. This study is to examine the selection of the good job sequence of 1%-5% upper group by the sampling method. The result shows that there is the set of 0.5%-5% job sequence group which has to same amount of performance measure with the optimal job sequence in the case of experiment of 2/n/F/F max. This indicates that the sampling job sequencing method is a useful job sequencing method to find the optimal or good job sequence with a little effort and time consuming. The results of ANOVA show that the two factors, number of jobs and the range of processing time are the significant factors for determining the job sequence at $\alpha$=0.01. This study is extended to 3 machines to machines job shop problems further.

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A Fundamental Study about Vibration Analysis of Plasma Rock Fragmentation Method (플라즈마 파암공법의 진동분석에 관한 기초적인 연구)

  • 윤지선;김상훈
    • Proceedings of the Korean Geotechical Society Conference
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    • 2001.03a
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    • pp.129-136
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    • 2001
  • Blasting method is used most engineering works for rock excavation. Blasting method is done much to upgrade of operation efficiency, contraction of construction period than other method. But blasting method happens damage by blasting vibration, nose and scattering. Therefore this study examined about effect, characteristic and application of Plasma method. To confirm effect measured vibration, noise and frequency, and analyzed data compare with general blasting.

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A Study on the Analysis of Steady Magnetic Fields by the Coupling of FEM and BEM (FEM과 BEM의 혼합적용에 의한 정상자계의 해석에 관한 연구)

  • 임달호;김찬오
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.34 no.7
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    • pp.276-282
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    • 1985
  • This study is concerned with the analysis of two-dimensional steady magnetic fields by the coupling of FEM and BEM. FEM(Finite Element Method)is most widely used as a method of numerical analysis and BEM (Boundary Element Method)is a newest method for it. And the results from this coupling method are compared and discussed with those of FEM only. Consequently, it is shown that to obtain the same accuracy of results the coupling method requires less calculating time and dimension than the FEM.

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Comparison of Attenuation Correction Methods for Brain SPECT Ima (Brain SPECT 영상의 Attenuation Correction 방법들에 대한 비교)

  • Jo, Jin U;Kim, Chang Ho;Na, Soo Kyung;Lee, Gui Won
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.120-125
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    • 2012
  • Purpose : The purpose of this study was to compare count between Chang's method and CT-based attenuation correction (AC-CT) among the attenuation correction (AC) methods for non-attenuation correction (AC-non) images of Brain SPECT (Single Photon Emission Computed Tomography). Materials and Methods : We injected $^{99m}Tc$ 37Mbq in a Hoffman 3D phantom filled with distilled water in the phantom study, and injected intravenously $^{99m}Tc$-HMPAO 740Mbq in a normal volunteer in the patient study, and then obtained Brain SPECT images with Symbia T6 of Siemens and conducted quantitative brain analysis. Transverse images to which each method was applied were rebuilt at the same position, and 6 regions of interest (ROI) were drawn on each of Slice No. 10, 20 and 30 and then the counts of AC-non, AC-CT and Chang's method were compared. Results : The mean counts of AC-non, AC-CT and Chang's method were $4606.8{\pm}511.3$, $16794.6{\pm}2429.4$, and $8752.6{\pm}896.5$, respectively, in the phantom study and $5460.8{\pm}519.6$, $15320{\pm}1171.6$ and $12795{\pm}1422.1$, respectively, in the patient study. In the phantom study, the ratio of AC-CT to AC-non was 3.70 and the ratio of Chang's method to AC-non was 1.92, and in the patient study, they were 2.85 and 2.38, respectively. Conclusion : From this study, we found that AC-CT makes higher AC than Chang's method. In addition, when Chang's method was used, AC in the patient study was higher than that in the phantom study. These results need to be considered also in other examinations.

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A Study on the Multiresidue Analytical Methods for Organophosphorus, Organochlorine, and n-Methyl carbamate Pesticides in Food (식품 중의 유기인제, 유기염소계 및 카바메이트계 농약의 다성분 분석법 비교)

  • Chun, Ock-Kyoung;Lee, Kang-Moon
    • Korean Journal of Environmental Agriculture
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    • v.18 no.2
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    • pp.154-163
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    • 1999
  • A multiresidue method(MRM) for pesticides must be rapid and must test a wide variety of pesticides at relevant toxicological concentrations. In this study, three kinds of major analytical methods such as Korean Food Code Method, CDFA MRM, and Holstege's method are tested to compare the average recoveries, solvent consumption, and required time for the analysis of 18 organochlorines, 18 organophosphates, and 6 carbamates in spinach samples. Samples for pesticides analysis were extracted and cleaned up according to the respective methods and detected by gas chromatography with selective detectors, ECD and NPD, HPLC with postcolumn reaction system(PCRS). Average recovery of 42 pesticides by Korean Food Code method, CDFA method, and Holstege's method were 91.3%, 88.1%, 89.0%, respectively. Amount of solvent consumption and required time for the analysis of Korean Food Code method were from two and a half times to three times as much as those of another two methods. For the development and legal application of more rapid and effective MRMs, prolonged study is necessary.

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Review on Geumnaeng Method - Focus on Chinese Medical Articles - (금냉법(金冷法)에 대한 고찰 - 중국 논문을 중심으로 -)

  • Park, Haemo
    • Journal of Society of Preventive Korean Medicine
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    • v.22 no.3
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    • pp.73-81
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    • 2018
  • Objectives : 'Geumnaeng method'' is a well-known folk remedy, but It has not been studied in academia. This study was conducted to review the chinese published articles on Geumnaeg method (Jinleng method) of Chinese traditional medicine. Methods : The author searched Chinese published papers from 2000 to 2018 via CNKI(China National Knowledge Infrastructure) database by using keyword 'Jinleng', 'Jinleng method', and analyzed the papers covered Jinleng method health preservation, and classified them including periods, type of study, target symptoms, and comparison between countries. Results : 17 studies were reviewed. The study of Jinleng method in China began in 2005. 8 articles (47.1%) were review articles, 4 articles (23.5%) of the case report and case series, and 5 articles (29.4%) were clinical studies. Clinical studies have increased since 2008. Most of the studies related to genital disorders and sexual function were mainly performed. There were differences between Japan, Korea and China in Jinleng method. Conclusions : Various disease and symptoms was researched with Jinleng method in China. Research in China is more active than other country. We need to increase the level of evidence of Jinleng method's effectiveness through additional studies in the future.

A field evaluation of two external transmitter attachment methods for small snakes

  • Park Il-Kook;Jeong, Hojun;Park, Daesik
    • Journal of Ecology and Environment
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    • v.46 no.3
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    • pp.183-189
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    • 2022
  • Background: Radio-telemetry is a useful method to investigate the spatial ecology of species in the wild, by tracking the signal of a transmitter attached to an individual. The method of attaching a transmitter to a snake is representatively divided into surgical implantation, and external attachment, which latter is often used in small snake species. Results: In this study, we evaluated and compared the utility of two external attachment methods, the nylon thread method and the tape method, applied to a small grassland snake species of approximately 50 cm snout-vent length, the Slender racer (Orientocoluber spinalis), on an island in the Republic of Korea. The nylon thread method and the tape method were applied to four and five individuals, and radio-tracked for an average of eight and eleven days, respectively. The nylon thread method caused individual injury and disturbed their movement, while using the tape method, the transmitter package sometimes dropped off, but no injury or movement problems occurred. Conclusions: Considering that poor understanding of how to attach the transmitter makes it difficult to investigate the spatial ecology of small snake species, the tape method, evaluated in this study, could be applied to attach a transmitter and to study spatial ecology of such snakes.

A Study on the River Discharge Measurement Techniques (하천유량 측정기법에 관한 연구)

  • 김성원;지홍기
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.793-801
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    • 1998
  • In this study, the Dilution Method is used to measure river discharge through the hydraulic model test. the dilution method is divided into Constant-Rate-Infection Method and Slug-Injection Method in the river discharge measurement techniques. When the dilution method is applied in the hydraulic model flume, it is analyzed that the estimated error of constant-rate-injection method is less than that of the slug-in-jection method, and the result shows that floodflow analysis is more efficient than lowflow analysis as compared observed discharge with calculated discharge. The result of statistical error analysis shows that the constant-rate-injection method is appropriate technique for the measurement of the river discharge. Therefore, the dilution method among the river discharge measurement techniques can be applied for the river basin which can't be measured with current meter or unsteady-flow regime in the urban-small drainage or hydraulic structure equipment area and can be obtained more exact results than any other discharge measurement techniques.

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Cost Analysis of Composite Method Using Hollow-PC Column (중공 PC기둥을 적용한 복합공법의 공사비 분석)

  • Park, Byeong-Hun;Kim, Jae-Yeob
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2016.10a
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    • pp.71-72
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    • 2016
  • Most of studies on PC method aim at the structural analysis and development of PC members, and studies on the construction management aspect are insufficient. Therefore, this study tries to investigate 'hallow PC column composite method(HPC composite method)' from the viewpoint of construction management and analyze the construction cost of the composite method. On the assumption that each comparative method was applied to the zone, the difference in construction cost between the two methods was analyzed. As a result, HPC composite method increased the initial investment cost because of its factor technology, but reduced transport cost, lifting cost, and installation cost through lightweight columns. This study analyzed only the difference in construction cost of HPC composite method so that it has the limitation in evaluating its economy. Therefore, to evaluate the economy of HPC composite method, it is considered to research more the construction cost of HPC composite method.

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A Study Regarding Current Usage of Ha-Taedok Method in Korean Pediatrician (소아 전문 한의사를 대상으로 실시한 하태독법의 인식 및 사용실태 조사)

  • Jeong, Min Jeong
    • The Journal of Pediatrics of Korean Medicine
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    • v.28 no.2
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    • pp.88-102
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    • 2014
  • Objectives This study is to know the current usage of Ha-Taedok Method in Korean pediatrician. Methods 69 questionnaires were statistically analyzed by using PASW Statistics 18. Results 55 Korean Medicine doctors knew Ha-Taedok Method, but only 2 doctors were using Ha-Taedok Method in their practice. The doctors tend not to use Ha-Taedok Method because it was hard to get permission from the patient's caregiver. 11 Korean Medicine doctors used Ha-Taedok Method to their own children though. The pediatricians felt satisfied from the effect of Ha-Taedok Method especially because it can prevent from disease. They reported no side effect and adverse effect. Coptidis Rhizoma is a preferred herb to use along with Ha-Taedok Method. For a better result from Ha-Taedok Method, it is recommended to start within 3 days old of patient. Conclusions Ha-Taedok Method may be effective as preventive method.