• 한국수산과학회지
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• 제25권6호
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• pp.520-528
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• 1992

식품의 가열살균공정의 최적화는 에너지 소비의 성력화를 위한 공정 자동화와 제품의 미생물학적 안전성 및 영양적, 기호적 품질을 감안하여 이루어져야 한다. 본 연구에서는 이미 개발한 마이크로컴퓨터를 이용한 자동화 시스템을 개선하여 미생물학적 안전성 확보를 위한 가열살균기준 설정에 필수적인 $F_o-값 측정 시스템을 개발하였다. $F_o-값은 가열살균 중인 명태 고기풀의 냉점에서의 온도변화에 따라 순간치사율(lethal rate)을 구하고 전체 공정에서의 치사율의 합(integrated lethality)을 $F_o-값으로 나타내었다. 또한 정확도는 냉점에서의 열침투곡선으로부터 계산된 열확산도의 정확도로써 검토하였다. $F_o-값은 다양한 온도에서의 미세한 조건의 변화에도 불구하고 정확한 측정이 가능하였다. 또한 다양한 조건에서 동시에 계산된 명태 고기풀의 열확산도는 문헌상에 보고된 추정식으로 구한 열확산도와 큰 차이를 보이지 않았으며, 그 차이는 $\pm12\%$이내였다.

• Nuclear Engineering and Technology
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• 제54권4호
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• pp.1421-1430
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• 2022

The computation of the solid angle and the detector efficiency is considering to be one of the most important factors during the measuring process for the radioactivity, especially the cylindrical γ-ray NaI(Tl) detectors nowadays have applications in several fields such as industry, hazardous for health, the gamma-ray radiation detectors grow to be the main essential instruments in radiation protection sector. In the present work, a generic numerical simulation method (NSM) for calculating the efficiency of the γ-ray spectrometry setup is established. The formulas are suitable for any type of source-to-detector shape and can be valuable to determine the full-energy peak and the total efficiencies and P/T ratio of cylindrical γ-ray NaI(Tl) detector setup concerning the truncated conical radioactive source. This methodology is based on estimate the path length of γ-ray radiation inside the detector active medium, inside the source itself, and the self-attenuation correction factors, which typically use to correct the sample attenuation of the original geometry source. The calculations can be completed in general by using extra reasonable and complicate analytical and numerical techniques than the standard models; especially the effective solid angle, and the detector efficiency have to be calculated in case of the truncated conical radioactive source studied condition. Moreover, the (NSM) can be used for the straight calculations of the γ-ray detector efficiency after the computation of improvement that need in the case of γ-γ coincidence summing (CS). The (NSM) confirmation of the development created by the efficiency transfer method has been achieved by comparing the results of the measuring truncated conical radioactive source with certified nuclide activities with the γ-ray NaI(Tl) detector, and a good agreement was obtained after corrections of (CS). The methodology can be unlimited to find the theoretical efficiencies and modifications equivalent to any geometry by essential sufficiently the physical selective considered situation.

• 한국식품영양과학회지
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• 제13권1호
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• pp.1-8
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• 1984

식품이 가지고 있는 고유한 색깔은 소비자의 기호성 또는 영양학적 가치의 지표가 될 수 있으며 가공 및 저장처리조건에 따른 식품의 중요한 인자로 작용 할 수 있다. 따라서, 본 실험에서는 식물성 식품재료의 품종, 성숙도, 성장조건(온도, 수분. 제조공정 별)에 따른 Surface color change를 color & color difference meter와 Munsell disc 색도계(色度計)로 X, Y, Z값을 측정하고 공식에 의하여 Y(one of variation in luminous reflectance), x, y(chromaticity)를 구하여 이로부터 작성한 색도좌표상에서 식품의 색상(hue) 및 강도(chroma)를 산출하여 식품의 색도 변화를 검토하였다. 이와 같이 color & color difference meter와 같은 reflectometer를 이용하여 얻은 data를 중심으로 각각의 chromaticity diagram을 작성, 식품의 저장 및 가공처리별 색도변화를 측정하여 이것을 토대로 식품 품질의 특성을 판정할 수 있는 좋은 기초자료를 얻을 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.2527-2538
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• 2011

The Reliability started for MILitary purposes during World War II in 1942, getting more important for maintenance, safety, etc in modern society. As technologies develop, also international standards for measuring the reliability is advancing. RAMS activities for maintenance, safety verification is material to national railroad. And for this, it needs quick response for the changes of standards. Even now standards are upgrading for developing electronic technologies. Therefore analysis of failure rate's trend about such standards is judged necessary. So We submit a this paper for comparative analysis of changing process standards according to development of electronic technologies and reliability. At first, we compared actual usage ratio of standards for understanding the current state of usage. Based of these state of usage, discuss the major standard. And then, introduced reliability standards's trend, calculation method of failure rate and difference of failure rate calculation standard according to march of time. In this paper, used standards are MIL-HDBK-217F, Telcodia, etc.

• 한국공작기계학회논문집
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• 제15권5호
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• pp.1-6
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• 2006

The purpose of this study is to develop to portable near infrared analyzer measuring the sugar content of the fruits on a tree before harvesting ones. The portable near infrared system consists of a tungsten lamp, a coaxial optical fiber bundle and a multi-channel detector, which has 256 pixels and a concave transmission grating. Reflectance NIR spectra of orange were recorded by using a coaxial optical fiber bundle. The spectra were collected over the spectral range $400{\sim}1100nm$. Partial least squares regression(PLSR) was applied for a calibration and validation for determination of sugar contents. The multiple correlation coefficient was 0.99 and standard errors of calibration(SEC) was 0.069 brix. The calibration model predicted the sugar content for validation set with standard errors of prediction(SEP) of 0.092 brix. The sugar content in fruits was successfully quantified using the portable near infrared analyzer.

• 한국항행학회논문지
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• 제13권6호
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• pp.861-875
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• 2009

소프트웨어 품질 및 신뢰성 확보를 위해서는 체계적인 소프트웨어 개발, 관리 및 조직적인 지원 등이 이루어져야만 한다. 이러한 소프트웨어 프로세스 개선모델로는 ISO/IEC 15504와 CMMI 등의 국제적 모델이 많이 사용되고 있다. 그러나 이러한 국제적 SPI 모델은 대규모의 조직이나 대규모 프로젝트를 적용대상으로 하고 있으며, 수행해야만 하는 활동과 프로세스가 많을 뿐만 아니라 프로세스 심사 또는 인증 시에 비용과 시간이 많이 소요되는 문제점이 있다. 본 논문은 CMMI, ISO/IEC 15504 및 국내 중소기업들이 프로세스 개선에 쉽게 적용가능 하도록 개발한 소프트웨어 프로세스 품질인증 모델인 K-모델의 특징을 서로 비교하고 K-모델을 기반으로 프로세스 심사, 개선 및 인증 시에 필요한 측정 메트릭스를 제시한다. 정량적이고 객관적인 프로세스 측정을 통하여 프로세스 개선이 쉽게 이루어질 수 있으며, 실험을 통하여 메트릭스의 타당성을 분석한다.

• 분석과학
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• 제8권4호
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• pp.427-434
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• 1995

Inductively coupled plasma mass spectrometry combined with the isotope dilution method is used for the determination of lithium. The isotope dilution method is based on the addition of a known amount of enriched isotope (spike) to a sample. The analyte concentration is obtained by measuring the altered isotope ratio. The spike solution is calibrated through so called reverse isotope dilution with a primary standard. The spike calibration is an important step to minimize error in the determined concentration. It has been found essential to add spike to a sample and the primary standard so that the two isotope ratios should be as dose as possible. Since lithium is neither corrosive nor toxic, lithium is used as a chemical tracer in the nuclear power plants to measure feedwater flow rate. 99.9% $^7Li$ was injected into a feedwater line of an experimental system and sample were taken downstream to be spiked with 95% $^6Li$ for the isotope dilution measurements. Effects of uncertainties in the spike enrichment and isotope ratio measurement error at various spike-to-sample ratios are presented together with the flow rate measurement results in comparison with a vortex flow meter.

• 한국CDE학회논문집
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• 제19권1호
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• pp.12-18
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• 2014

Shot-peening is frequently used on various mechanical parts because it can improve the fatigue life of components by generating compressive residual stresses on the surface. This can be done by repeatedly hitting the work-piece surface with small balls and making indentations on it. In fact, finding optimal peening time among various peening parameters is the most important. Under-peening can not improve the fatigue life sufficiently while over-peening causes cracks and reduces fatigue life in contrast. In general, optimal peening time is experimentally determined by measuring arc-height using Almen-strip in accordance with SAE J442 standard. To save the time and efforts spent in carrying out experiments to find optimal peening time, this paper presents a computer simulation algorithm for the estimation of surface coverage made by impeller type shot-peening machines (PMI-0608). Surface coverage is defined as the proportion of the work-piece surface that has been indented in a given time of shot-peening. An example (standard tensile test specimen) is presented to validate the proposed method.

• 한국해양공학회지
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• 제8권2호
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• pp.38-46
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• 1994

The method of JSME S001-83 and ASTM E813-87 have been adapted for evaluation of the elastic-plastic fracture toughness J sub(IC) of SB41 steel. This SB41 steel have the characteristics of low-stength CT specimens. The test results obtained have been considered and compared on the basis of resulted data from two kinds of methods(JSME S001-83, ASTM E813-87) and two kinds of specimen configurations(smooth, side-grooved). On the basis of results from consideration and comparison, the difficulties for its application were presented in case when the standard ASTM E813-87 method was employed for the measurement of J sub(IC) in SB41 steel. A modified method was applied for measuring J sub(IC) in SB41 steel that it used the blunting line real-measured by experiment instead of the standard blunting line theoretically determined, and the result from that procedure was analyzed and the usefulness of that method was examined and considered.

• 한국통신학회논문지
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• 제42권2호
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• pp.432-443
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• 2017

MPEG-H 3D 오디오 표준은 UHDTV 등의 초고해상도 방송서비스에 대응하는 실감음향 서비스의 제공을 목표로 한다. 이를 위해 본 표준은 다채널 신호, 객체 신호, 장면 기반 신호의 부호화/복호화 기술과 다양한 재생 환경에서 3차원 오디오 제공을 위한 렌더링 기술, 후처리 기술 등 방대한 기술을 통합하였다. 본 표준의 참조 소프트웨어 복호화기는 여러 모듈들이 결합된 구조로 다양한 모드에서 동작이 가능하며, 각 모듈들이 독립된 실행파일로 순차적으로 실행되어 실시간 처리가 불가능하다. 본 논문에서는 MPEG-H 3D 오디오의 코어 복호화기, 포맷 변환기, 객체 렌더러, 바이노럴 렌더러의 각 함수를 동적 라이브러리화 및 통합하여 프레임 기반 복호화가 가능하도록 하였다. 또한 MPEG-H 3D 오디오의 각 모드별 연산량을 측정하여 다양한 하드웨어 플랫폼에서 적합한 모드를 선택하기 위한 참고 자료를 제공한다. 연산량 분석 결과, 한국 방송 표준에 포함된 저연산량 프로파일은 채널 신호로 렌더링을 할 경우 QMF 합성 연산의 2.8배에서 12.4배의 연산량을 가지며, 바이노럴 렌더링을 할 경우 QMF 합성 연산의 4.1배에서 15.3배의 연산량을 가진다.