• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.2
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• pp.22-26
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• 1981

Truncated expansions based upon the sampling theorem but containing only a few terms can be very useful for practical interpolations of band-limited or narrow-band random signals. The major goal of this work is to find and coiupare efficient and "statistically accurate" algorithms for the dynamic analysis of the ocean systems. The stalistical accuracy of truncated sampling interpolations is investicated, and one simple ocean systems, which yields a Runge-Kutta simulation algorithm of improved accuracy with very little increase in computation, is indicated.indicated.

• Structural Engineering and Mechanics
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• v.5 no.2
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• pp.115-126
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• 1997

Importance sampling methods have been developed with the aim of reducing the computational costs inherent in Monte Carlo methods. This study proposes a new algorithm called the adaptive kernel method which combines and modifies some of the concepts from adaptive sampling and the simple kernel method to evaluate the structural reliability of time variant problems. The essence of the resulting algorithm is to select an appropriate starting point from which the importance sampling density can be generated efficiently. Numerical results show that the method is unbiased and substantially increases the efficiency over other methods.

• Korean Management Science Review
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• v.33 no.3
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• pp.89-103
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• 2016

In this paper, we design sampling inspections and service capacities simultaneously for multi-products. Products are supplied in batches after rectifying inspections, that is, rejected lot is subject to total inspection and defective products are reworked to good ones. When supplied, all defective products are uncovered and returned to service. Particularly, we extend Kim [1] by introducing the fixed costs of providing services and show that the cost function of a product is no longer linear or convex in terms of the level of service provision. We develop a framework for a product to deal with this joint design problem and a dynamic programming algorithm for multi-products which allocates the given number of the total service capacities among products with the considerably smaller computations than the total number of possible allocations.

• Journal of Environmental Science International
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• v.21 no.6
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• pp.713-724
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• 2012

Emission rates of biogenic hydrocarbon emitted from broad-leaved trees grown at Jeju Island were estimated using a dynamic enclosure method. Leaf temperature, PAR and relative humidity were monitored during the sampling time. The emission rates of isoprene and monoterpene were measured for five plants(Carpinus laxiflora, Quercus serrata, Styrax japonicus, Quercus acutissima, Quercus crispula) during the sampling period at the Halla mountain sites. Among five tree species, the highest isoprene emission rate of 10.60 ${\mu}g\;gdw^{-1}hr^{-1}$ was observed for Quercus serrata. The seasonal emission rates were the highest during summer and the emission of isoprene was highly affected by light and temperature variations. The highest emission rate of isoprene was occurred between 13:00 and 14:00, but isoprene was not emitted in nighttime because of the absence of light.

• The Journal of the Korea institute of electronic communication sciences
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• v.7 no.2
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• pp.295-301
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• 2012

In this article, we have designed SHA, which has 12 Bit resolution at an input signal range of 1 $V_{pp}$ and operates at a sampling speed of 100 MS/s in order to use at front of high speed ADC. SFDR(Spurious Free Dynamic Range) of the proposed system drops to approximately 66.3 dB resolution when the input frequency is 5 MHz, and the sampling frequency is 100 MHz, however, the circuit without a feedthrough has 12 bit resolution with approximately 73 dB.

• Proceedings of the KIEE Conference
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• 2007.04a
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• pp.125-127
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• 2007

현재 차량 내 네트워크에서 주로 쓰이는 CAN 프로토콜은 네트워크 내에 다수의 노드가 연결되어 동작하는 경우 우선순위가 낮은 메시지의 전송지연이 심각하게 발생할 수 있다. 이를 해결하기 위해 다양한 제어 방법들이 제안되어 시험되고 있는데, 본 논문에서는 동적 ID 차당 기법을 연로전지 하이브리드 자동차 네트워크 시스템에 적용하여 각 장치들간의 메시지 전송 지연문제를 해결 하며, 또한 이로 인해 발생하는 차량 내 네트워크 시스템의 수행 주기 변화의 문제점을 샘플링 주기 결정 기법을 이용하여 효율적으로 해결하였다.

• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.36-39
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• 2005

Information on temporal evolution of whole velocity fields is essential for physical understanding of a complicated turbulent flow and was obtainable using dynamic PIV because of advances of high-speed imaging technique, laser and electronics. A dynamic PIV systme consists of a high-speed CMOS camera having $1K\times1K$ pixels resolution at 1 KHz and a high-repetition Nd:Yag pulse laser. In order to validate its performance, the dynamic PIV system was applied to a turbulent jet whose Reynolds number is about 3000. The particle images of $1024\times512$ pixels were captured at a sampling rate of 4 KHz. The dynamic PIV system measured successfully the temporal evolution of instantaneous velocity fields of the turbulent jet, from which spectral analysis of turbulent structure was also feasible.

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.96-96
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• 2002

목적： MRI 시스템의 비약적인 발전으로 인하여, 시스템에서 발생되는 noise가 상당히 줄었다. 따라서 시스템에서 발생되는 random noise뿐만 아니라 sampling 과정에서 발생되는 quantization noise도 중요하게 고려하여야 할 요소가 되었다. 특히, MRI 신호의 경우 dynamic range가 크기 때문에 bit 수가 큰 ADC를 이용하여 데이터를 얻어야 한다. 그러나, bit 수가 크고 높은 sampling rate를 갖는 ADC의 경우 가격이 높을 뿐만 아니라, 기존의 장비를 교체해야하는 어려움이 있다. 본 연구는 oversampling과 quantization noise와의 관계를 컴퓨터 시뮬레이션을 통하여 알아보고, MRI영상에서 oversampling을 통하여 quantization noise를 줄임으로써 영상의 질을 개선하고자 한다.

• Analytical Science and Technology
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• v.9 no.4
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• pp.399-405
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• 1996

The flavor compounds of the oil from roasted sesame seeds were collected by simultaneous steam distillation/ extraction(SDE) and dynamic headspace sampling(DHS) and were analyzed using a gas chromatograph equipped with a flame ionization detector and connected into a mass spectrometer. Among the flavor compounds collected by the SDE method, 46 compounds were identified. They consisted of 6 alcohols, 6 aldehydes, 5 ketones or acids, 4 furans or phenols, 12 pyrazines, 4 pyridines or thiazoles, and others. Thirty six compounds were identified by DHS and many of them were the same as those identified by the SDE method. However, some compounds such as 1-hexanol, pentanal, and dimethylsulfide were identified only by the DHS method.

• Journal of Environmental Impact Assessment
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• v.14 no.5
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• pp.263-273
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• 2005

In this study, the major emission procedures and emission characteristics were identified at the site of sewage treatment plant which is one of the major sources of ammonia. At the same time the emission factors and emission rates were estimated. In order to calculate the emission flux, we used a Dynamic Flux Chamber(DFC), which is found to be a proper sampling devise for area sources such as sewage treatment plant. It was found that the most stable sampling condition was when the stirrer's speed of DFC was 120RPM, and it would be the best time to take a sample 60 minutes later after setting the chamber. The relatively higher flux was shown in Autumn compared to summer and winter. Annual ammonia emission rates procedures were calculated as $906.32{\mu}g/activity-ton$, $1,114.72{\mu}g/activity-ton$ and $437.53{\mu}g/activity-ton$ each at the primary settling basin, aeration basin and the final settling basin, respectively. The ammonia emission rate the highest at in the aeration basin according to this test. This results was due to that the surface of aeration basin or the final settling basin is relatively wider than the primary settling basin.