• Journal of the Optical Society of Korea
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• 제18권5호
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• pp.531-537
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• 2014

Through-silicon vias (TSVs) are fine, deep holes fabricated for connecting vertically stacked wafers during three-dimensional packaging of semiconductors. Measurement of the TSV geometry is very important because TSVs that are not manufactured as designed can cause many problems, and measuring the critical dimension (CD) of TSVs becomes more and more important, along with depth measurement. Applying white-light scanning interferometry to TSV measurement, especially the bottom CD measurement, is difficult due to the attenuation of light around the edge of the bottom of the hole when using a low numerical aperture. In this paper we propose and demonstrate four bottom CD measurement methods for TSVs: the cross section method, profile analysis method, tomographic image analysis method, and the two-dimensional Gaussian fitting method. To verify and demonstrate these methods, a practical TSV sample with a high aspect ratio of 11.2 is prepared and tested. The results from the proposed measurement methods using white-light scanning interferometry are compared to results from scanning electron microscope (SEM) measurements. The accuracy is highest for the cross section method, with an error of 3.5%, while a relative repeatability of 3.2% is achieved by the two-dimensional Gaussian fitting method.

• Environmental Engineering Research
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• 제12권4호
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• pp.176-193
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• 2007

The ability to measure groundwater contaminant flux is increasingly being recognized as crucial in order to prioritize contaminated site cleanups, estimate the efficiency of remediation technologies, measure rates of natural attenuation, and apply proper source terms to model groundwater contaminant transport. Recently, a number of methods have been developed and subsequently applied to measure contaminant mass flux in groundwater in the field. Flux measurement methods can be categorized as either point methods or integral methods. As the name suggests, point methods measure flux at a specific point or points in the subsurface. To increase confidence in the accuracy of the measurement, it is necessary to increase the number of points (and therefore, the cost) of the sampling network. Integral methods avoid this disadvantage by using pumping wells to interrogate large volumes of the subsurface. Unfortunately, integral methods are expensive because they require that large volumes of contaminated water be extracted and managed. Recent work has investigated the development of an integral method that does not require extraction of contaminated water from the subsurface. We begin with a review of the significance and importance of measuring groundwater contaminant mass flux. We then review groundwater contaminant flux measurement methods that are either currently in use or under development. Finally, we conclude with a qualitative comparison of the various flux measurement methods.

• 품질경영학회지
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• 제45권3호
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• pp.533-547
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• 2017

Purpose: This study proposes the main sources of uncertainty and uncertainty analysis of a measurement system of insensitive munitions tests. Methods: We established the mathematical model for calculating measurement uncertainty of insensitive munitions tests, conducted experiments for calculating uncertainties of dynamic sensitivity and overshoot value, and estimated the distributions of uncertainty factors. Results: The measurement uncertainty calculation methods are presented, which include experimental data processing methods for calculating uncertainties of dynamic sensitivity and overshoot value. Conclusion: The measurement of explosion pressure in insensitive munitions tests is an important issue to the reporting test results and classifying reaction types. The more efforts to ensure the reliability of the insensitive munitions tests results are required.

• 전력전자학회논문지
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• 제5권6호
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• pp.552-559
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• 2000

유도전동기의 센서리스 벡터제어 방식은 선동기 등가모델을 이용하는 경우가 대부분이다. 따라서 센서리스 벡터 제어 기능을 갖는 인버터에 전동기 상수의 자동 측정 가능은 필수적이며, 전동기 상수 측정의 정밀도가 센서리스 벡터제어 인버터의 성능에 큰 영향을 미친다. 본 논문에서는 기존의 자동 측정 방법에 있어서의 문제점을 고찰하고, 이를 보완한 새로운 유도전동기 상수 측정 방법을 제시한다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2005년도 추계학술대회논문집
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• pp.359-362
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• 2005

Road traffic noise level and railway noise level are important factors on apartment inhabitant's comforts. The measurement methods which noted by Ministry of Construction & Transportation(MOCT) and Ministry of Environment(ME) are used for measurement of exterior noise at apartment houses. But these methods are out of date because the height of apartment houses have increased dramatically and owing to the sampling methods of the measurement time interval, rating values are induced differently due to sampling methods. In this study, the sound level of each floor of apartment houses is measured and compared. And rating value due to sampling methods are compared. As a result, the KS outline of 'Field Measurement of Exterior Noise at Apartment Housess' is suggested.

• 대한기계학회논문집B
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• 제25권4호
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• pp.561-571
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• 2001

The standard uncertainty of flowrate measurement is obtained by combining that of independent variables. Gravimetric and volumetric method were applied to determine the flowrate and the standard uncertainties of flowrate measurement by both methods were evaluated in accordance with the procedure recommended by International Organization for Standardization. The combined standard uncertainties of determining the flowrate were estimated from the sensitivity coefficient and the standard uncertainty of independent variables. For practical application, the methods for evaluating and expressing uncertainty in flow measurement were discussed. It was found that the uncertainties of the weighing and time measurement in gravimetric method, the volume and time measurement in volumetric method have dominant influence on that of flowrate measurement. With the quantitative analysis of the sensitivity coefficient, the contribution of the each variable uncertainty to the combined standard uncertainty of flowrate measurement is shown clearly.

• Journal of Acupuncture Research
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• 제29권5호
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• pp.127-137
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• 2012

Objectives : The purpose of this study is to review on current status of use and measurement condition of heart rate variability(HRV) by reviewing clinical studies published in journal of Korean medicine registered Korea citraion index(KCI). Methods : One hundred twenty articles were found by searching the representative Korean databases. At first analysis was performed by current status of use(journal, academic field of corresponing author, purpose of study, disease of subject, HRV measurement devices, intervention methods and tests compared to HRV). At second analysis was performed by measurement condition(uncontrolled study, relaxation before measurement, measurement position, measurement place, measurement time period and restriction of smoking, alcohol, caffeine, meal). Results : The analysis showed that department of acupuncture & moxibustion, department of oriental neuropsychiatry are major part in journal & academic field. The purpose of study were classified under studies to verify therapeutic effect on normal subject(39%), to verify therapeutic effect on the patients(8%), to investigate characteristics of the patients(34%) and to be compared with other test(19%). Disease of subject & measurement devices in article were so various. Major intervention methods were acupuncture(61.4%), mind-body intervention(19.2%). Studies that measurement condition were not controlled were relax time(24%), measurement position(19%), measurement place(26%), measurement time period(91%) and restriction of smoking, alcohol, caffeine, meal(49%). Conclusions : This study showed that current status of use of HRV is widespread in Korean medicine but more controlled measurement conditon are needed to get more reliable result from clinical studies and to improve diagnosis and treatment of Korean medicine.

• 한국도로학회논문집
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• 제14권2호
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• pp.165-174
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• 2012

본 연구에서는 차량검지기의 속도측정 성능평가방법을 개발하였다. 개발된 성능평가방법에서는 오차요인들을 기준속도에 반영하며 측정불확도의 개념을 적용하였다. 기존연구, 통계적 처리기법, 기존교통단속장비 및 차량검지시스템의 속도측정 성능평가방법 등에 대한 고찰을 통해 기존평가방법의 문제점을 도출하고 개선된 성능평가방법을 개발하였다, 실제 현장에 설치된 차량검지기에 대해서 기존평가방법과 개발방법을 적용해본 결과 기존평가방법은 평가기준에 적합하나 개발방법은 평가기준을 만족시키지 못하고 있다. 이러한 결과는 기존성능평가방법이 측정 시의 오차요인들을 충분히 고려하지 못해서 평가대상장비의 성능을 고평가할 가능성이 있음을 의미하며, 반면에 개발모형은 측정 시의 변동요인인 오차를 고려하므로 기존평가방법 보다 정확함을 나타낸다.

• 한국환경보건학회지
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• 제42권5호
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• pp.314-323
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• 2016

Objectives: Time location data are critical for accurately estimating personal exposures. This review papers summarized various measurement methods of time location pattern for air pollution exposure assessment. Methods: Forty manuscripts (papers, books and reports) were reviewed to comprehensively describe time location measurement methods. Results: This review included traditional methods such as time activity diary, questionnaire, observation, focus group and newly developed technical methods including global positioning system, web, radio frequency identification and ultrasound detection. Some research applied a combination of methods. Conclusion: Although various methods have been used to collect time location data, further development of accurate measurement methods for time location data is needed.

• 대한인간공학회지
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• 제22권3호
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• pp.75-91
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• 2003

Evaluation of repetitiveness for hand-intensive tasks is essential to determine the level of risk for upper-extremity musculoskeletal disorders at the workplace. Many measures and methods have been introduced for repetitiveness assessment: however, our understanding of the differences among these measures and methods is lacking. The present study compared the repetitiveness measures and measurement/analysis methods to help practitioners apply the proper repetitiveness assessment methodology in the workplace. By reviewing 51 studies of repetitiveness assessment, measures and corresponding measurement/analysis methods were surveyed. Of the repetitiveness measures, two types of dimensions (frequency and time) and corresponding types of analysis scopes were identified. According to the dimensional and analysis-scope types. the repetitiveness measures were categorized and then the surveyed studies were counted for each measure. It is identified that frequency measures have used 2.7 times higher than time measures and the frequency of wrist motions has been most frequently used in repetitiveness assessment. Furthermore, the measurement methods were categorized into objective and subjective methods, and the analysis methods into statistical and spectral methods. Lastly, eight factors (accuracy, reliability. sensitivity. efficiency. ease of use. applicability. interference. and robustness) were listed to be considered in selecting the appropriate assessment methodology.