• 제목/요약/키워드: important sampling

검색결과 1,344건 처리시간 0.026초

베이지안 기법을 이용한 염해 콘크리트 구조물의 내구성 평가 (Durability Assesment for Concrete Structures Exposed to Chloride Attack Using a Bayesian Approach)

  • 정현준;지광습
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2007년도 정기 학술대회 논문집
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    • pp.589-594
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    • 2007
  • This paper is shown new method for durability assesment and design have been noticed to be very valuable has been successfully applied to predict concrete structures. This paper provides that a new approach for predicting the corrosion durability of reinforced concrete structures exposed to chloride attack. In this method, the prediction can be updated successive1y by the Bayesian theory when additional data are available. The stochastic properties of model parameters are explicitly taken into account into the model the probability of the durability limit is determined from the samples obtained from the Latin hypercube sampling technique. The new method may be very useful in designing important concrete structures and help to predict the remaining service life of existing concrete structures under chloride attack environments.

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압축센싱 기반의 무선통신 시스템

  • 르나탄;신요안
    • 전자공학회지
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    • 제38권1호
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    • pp.56-67
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    • 2011
  • As a result of quickly growing data, a digital transmission system is required to deal with the challenge of acquiring signals at a very high sampling rate, Fortunately, the CS (Compressed Sensing or Compressive Sensing) theory, a new concept based on theoretical results of signal reconstruction, can be employed to exploit the sparsity of the received signals. Then, they can be adequately reconstructed from a set of their random projections, leading to dramatic reduction in the sampling rate and in the use of ADC (Analog-to-Digital Converter) resources. The goal of this article is provide an overview of the basic CS theory and to survey some important compressed sensing applications in wireless communications.

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Research on the Making Technology of Virtual Orchestral Instrument

  • Wang, Yan
    • 한국컴퓨터정보학회논문지
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    • 제22권1호
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    • pp.77-87
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    • 2017
  • In this paper, we propose an analysis of the sound source of virtual orchestral music in detail by using the production technology of sampling and playback, and technical experiments and verification for the most advanced Hollywood Library series of timbre and the timbre production and control technology of Vienna instrument Pro and other softwares, to find their solutions and come up with the best timbre production method for orchestral music from the perspective of the specific design ideas of the productions of virtual orchestral instruments. The so-called virtual orchestral instruments are non-real orchestral instruments, which are based on the imitation of timbre of real orchestral instruments, processed and synthesized through the scientific and technological means, and produced by the use of electronic equipments or computers. The study of virtual timbre production technology is very important, and it is like the study of composers' creative techniques. Not only scientific and advanced timbre production methods can be obtained from the study, but also new ways of future timbre production are expected to be explored.

Sequence sampling에 의한 단결정(Al$_2$O$_3$) 성장 제어 (Al$_2$O$_3$ Growth control by sequence sampling)

  • 조현섭;송용화;민병조
    • 한국산학기술학회:학술대회논문집
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    • 한국산학기술학회 2000년도 추계학술대회
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    • pp.181-184
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    • 2000
  • It is a quite quality concerning to control temperature of single crystalline it does when you get most of heat treating Products. It is also important control temperature when you make the A1203(single crystalline) used to jewels, 91ass of watches. heat resistant transparent 91asses. Thus, it is a md to get the proper temperature in accordance with the time process while making mixture of oxygen and hydrogen to have the right temperature. In we will study of electrical valve positioning system for the gas mixture to im quality of Products.

DSP를 이용한 자기공명영상의 경사자계 파형 발생기 개발 (Development of MRI gradient waveform generator using DSP)

  • 고광혁;권의석;송영철;김휴정;김치영;안창범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 G
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    • pp.3147-3149
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    • 1999
  • In this paper, we develop a TMS320C31- 60 DSP board to generate spiral gradient waveforms for Spiral imaging, one of the ultra fast MRI methods. In Spiral imaging, accurate gradient waveforms are very important to acquire high quality image. For this purpose, sampling rate for generating the gradient waveforms is set twice as high as the data sampling rate. With the developed DSP board accurate gradient waveforms are obtained. Ultra fast MR image with the developed DSP board is currently under development.

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Green Employee Empowerment? Driving and Inhibiting Factors for Green Employee Performance

  • ADI, Nyoman Rasmen;MULYADI, Made;SETINI, Made;ASTAWA, Nengah Dasi
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.293-302
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    • 2021
  • Being able to survive during the Covid19 pandemic is a big task for a company, as such, empowerment of employees is a must. The sample in this study was 300 employees who worked in Spas throughout Bali. The sampling technique was purposive sampling. Data analysis was using SEM and SMARTS as data processing. The results showed that green communication, namely communication that occurs between employees, superiors, and the environment, has a very good influence on the sustainability of employee performance. To become green management, a green organizational commitment that cares about the safety of employee health and the environment is an important factor as motivation in green dedication or positive employee productivity, but communication between work actors and justice is also a motivating factor. Work safety and job security for employees empower employees (which is a green line), especially for freelance work organizations so that further research in subsequent studies can make samples in a more varied industrial sector.

New record of Folsomia quadrioculata(Tullberg, 1871) and redescription of Folsomia octoculata(Handschin, 1925) from the forest of South Korea

  • Lee, Yun-Sik;Cho, Kijong;Park, Kyung-Hwa
    • 환경생물
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    • 제37권1호
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    • pp.1-7
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    • 2019
  • During a recent study to understand an interaction of Collembola community and their environmental factors, two species in the genus Folsomia, F. quadrioculata Tullberg 1871 and F. octoculata Handschin 1925, were found in the forest of South Korea. From 2013 to 2015, these two species were sampled from six mountains and F. quadrioculata or F. octoculata was the dominant species in 5 sampling sites among 6 sampling sites. F. quadriocualta and F. octoculata were found in litter of deciduous and pine forest, respectively. Therefore, the major tree species seems to be one of the important factors determining their habitat. F. quadiroculata is newly recorded from the Korean Peninsula and F. octoculata is redescribed based on new materials from South Korea.

순차적 크리깅모델의 평균-분산 정확도 검증기법 (Mean-Variance-Validation Technique for Sequential Kriging Metamodels)

  • 이태희;김호성
    • 대한기계학회논문집A
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    • 제34권5호
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    • pp.541-547
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    • 2010
  • 메타모델의 정확도를 엄밀하게 검증하는 것은 메타모델링에서 중요한 연구주제이다. k 점 선택교차검증기법이 많은 계산시간을 요구하면서도 메타모델의 정확도를 정략적으로 측정하지 못한다. 최근들어, 평균 $_0$ 기준이 메타모델의 정확도를 정량적으로 제공하기 위하여 제안되었다. 그러나 평균 $_0$ 검증 기준은 크리깅 메타모델이 부정확함에도 불구하고 일찍 수렴하는 경향이 있다. 따라서 본 연구에서는 최대엔트로피를 이용한 순차적 실험계획에서 크리깅모델의 평균과 분산을 이용한 정확도 평가기법을 제안한다. 이 제안한 기법은 평균 및 분산을 계산할 때 수치해석으로 구하는 것이 아니라 크리깅메타모델을 직접 적분하여 구하기 때문에 k 점 선택교차검증기법보다 효율적이며 정확하다. 제안한 기준은 실제 응답의 평균제곱오차의 경향과 매우 유사하여 순차적 실험계획의 수렴기준으로 사용할 수 있다.

캐니스터와 Tedlar-bag 시료채집법을 이용한 대기 중의 휘발성유기황화합물의 측정 (Measurement of Volatile Organic Sulfur Compounds in Ambient Air by Canister and Tedlar-bag Sampling Method)

  • 전선주;허귀석
    • 한국대기환경학회지
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    • 제15권4호
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    • pp.417-428
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    • 1999
  • The measurement of VOSCs(volatile organic sulfur compounds) in the air is nowadays a very important environmental research field. It is, however, very difficult because the concentration of the VOSC in ambient air is usually very low and the high reactivity makes it difficult to keep in container without loss of recovery. In this study, sampling method with cryogenic preconcentration is evaluated for analysis of atmospheric VOSC such as $CH_3SH,\;CH_3CH_2SH,\;CH_3SCH_3,\;CS_2,\;CH_3SSCH_3,\;CH_3SCH_2SCHA_3,\;and\;C_2H_5SSC_2H_5$ analyzed by GC-MS or GC-FID. Repeatabilities of measurement accompanied with preconcentration for 3-successive runs were in the range of 0.2~1.0% as a relative standard deviation. Stabilities up to 13 days were measured in 6 L canister and 10 L tedlar bag filled with VOSCs in ppb level. Higher stability was observed in tedlar bag as compared to canister with glass coated inner walls, and thiol compounds show dramatic losses in canister within 2~3 days. It is found that recovery over 70% was obtained in a week for all tested VOSCs when the compounds from ambient air matrix were stored in tedlar bag. It is also found that the stabilities of VOSCs are depending on humidity and coexisting compounds in matrix gas due to sample adsorption onto inner surface and reactivity. The results indicate the possibility and limitations of VOSC analysis in ambient air using container sampling method with cryogenic preconcentration.

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양산점토의 비배수 특성에 대한 시료교란의 효과 (The Effects of Sample Disturbance on Undrained Properties of Yangsan Clay)

  • 김길수;임형덕;이우진
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2000년도 봄 학술발표회 논문집
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    • pp.639-646
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    • 2000
  • It is important to estimate the mechanical properties of clay since it is directly related to the design and the construction of geotechnical structures. Site exploration, which is composed of boring, sampling, in-situ, or laboratory tests, is preformed to estimate the mechanical properties. However, mechanical properties of clay measured from laboratory test may be different from in-situ properties due to disturbances occurred during sampling, transportation, storage, and trimming. In this study, the degree of disturbance according to sampling method was estimated with the test results of CK/sub o/U triaxial compression test on Yangsan clay. The soil samples were obtained by three types of sampling method, j.e., 76mm-tube sampler, 76mm-piston sampler, and block sampler. In order to evaluate the quality of samples, volumetric strain, undrained shear strength, secant Young's modulus, and pore pressure coefficient at peak measured from each sample were compared with one another. From the test results, it was observed that mechanical properties of the block and piston samples were more reliable than those of tube samples. But it was observed that the water content of piston was similar to that of tube samples at given depths while the water content of block samples was 14.3∼15.8% smaller than that of piston and tube samples. In addition to the evaluation of the quality of samples, relationship between c/sub u// σ/sub vc/'and OCR was established from the results of the CK/sub o/U triaxial compression tests, which were carried out using SHANSEP method. And also undrained shear strength was analyzed using the in-situ test data such as Cone Penetration Test(CPT), Dilatometer Test(DMT), and Field Vane Test(FVT) and was compared with that evaluated from CK/sub o/U triaxial compression test.

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