• 응용통계연구
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• 제8권1호
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• pp.27-38
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• 1995

본 논문에서는 사회적으로나 개인적으로 매우 민감한 조사에서 모집단이 양적속성을 갖는 여러 개의 층으로 구성되어 있을 때, 층의 크기를 모르는 경우 층화표본을 위하여 이중추출법을 이용하는 층화이중추출법에 의한 양적속성의 무관질문모형을 제안하였다. 그리고, 층화이중추출에 있어서 각 층의 표본배분에 관해 비례배분, 최적배분으로 나누어 각 층의 크기를 알고 있는 경우에 층화추출법에 의한 양적속성의 무관 질문모형과 그 효율성을 비교하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.107.1-107
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• 2001

In this paper, a digital signal processing circuit for Position Sensitive Detectors(PSDs) is introduced to substitute the conventional analog signal processing circuit and to compensate disadvantages of the PSD. In general, the analog circuits have the problems such as noise accumulation, sensitivity for environmental changes, and high cost for manufacturing. Moreover, the intrinsic nonlinearity problem of the PSD makes it hard to measure the position accurately because it is difficult to be overcome the problem by using the conventional analog circuits, which can be solved by using the digital signal processing circuit. The circuit is implemented by using a Field Programmable Gate Array (FPGA). The Pulse Amplitude Modulation(PAM) method is used for reducing the environmental noise effect, and a linear interpolation logic is used to compensate the ...

• Bulletin of the Korean Chemical Society
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• 제29권5호
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• pp.988-992
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• 2008

A poly(methyl red) film-modified glassy carbon electrode (PMRE) was fabricated for determination of norfloxacin (NFX). The electrochemical behavior of NFX was investigated and a well-defined oxidation peak with high sensitivity was observed at the film electrode. PMRE greatly enhanced the oxidation peak current of NFX owing to the extraordinary properties of poly(methyl red) film. Based on this, a sensitive and simple voltammetric method was developed for measurement of NFX. A sensitive linear voltammetric response for NFX was obtained in the concentration range of $1\;{\times}\;10^{-6}\;-\;1\;{\times}\;10^{-4}$ mol/L and the detection limit was $1\;{\times}\;10^{-7}$ mol/L using linear sweep voltammetry (LSV). The proposed method possessed advantages such as low detection limit, fast response, low cost and simplicity. The practical application of this new analytical method was demonstrated with NFX pharmaceuticals.

• 한국세라믹학회지
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• 제55권1호
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• pp.1-20
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• 2018

Semiconducting nanomaterials have attracted considerable interest in recent years due to their high sensitivity, selectivity, and fast response time. In addition, for portable applications, they have low power consumption, lightweight, simple in operation, a low maintenance cost. Furthermore, it is easy to manufacture microelectronic sensor structures with metallic oxide sensitive thin layers. The use of semiconducting metal oxides to develop highly sensitive chemiresistive sensing systems remains an important scientific challenge in the field of gas sensing. According to the sensing mechanisms of gas sensors, the overall sensor conductance is determined by surface reactions and the charge transfer processes between the adsorbed species and the sensing material. The primary goal of the present study is to explore the possibility of using semiconducting mixed metal oxide nanostructure as a potential sensor material for selective gases.

• 한국분무공학회지
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• 제9권4호
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• pp.67-76
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• 2004

Diode laser absorption sensors are advantageous because they may provide fast, sensitive, absolute, and selective measurements of species concentration. These systems are very attractive for practical applications owing to its compactness, reasonable cost, robustness, and ease of use. In addition, diode lasers we fiber-optic compatible and thus enable simultaneous measurements of multiple species along a line-of-sight. Recent advances of room-temperature, near-IR and visible diode laser sources for telecommunication, optical data storage applications make it possible to be applied for combustion diagnostics based on diode laser absorption spectroscopy. Therefore, combined with fiber-optics and high sensitive detection strategies, compact and portable sensor systems are now appearing for variety of applications. The objectives of this research are to develop new gas sensing system and to verify feasibility of this system. Wavelength modulation spectroscopy has been demonstrated in these experiments and has a bright prospect to this diode laser system.

• 국제초고층학회논문집
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• 제10권2호
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• pp.123-135
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• 2021

Solid Viscoelastic Coupling Dampers (VCDs) provide distributed damping that improves the dynamic performance of tall buildings for both wind-storms and earthquakes for all amplitudes of vibration. They are configured in place of typical structural members in tall buildings and therefore do not occupy any architectural space. This paper summarizes the research and development at the University of Toronto in collaboration with Nippon Steel Engineering, 3M and Kinetica over the past two decades. In addition, impact studies on buildings incorporating the VCDs are presented, consisting of a wind sensitive 66-story building in Toronto, a dual-wind and seismic performance-based design of a 4-tower development in Manila and finally a 630 meter Megatall building in Southeast Asia in a severe seismic environment. In all applications the VCDs are shown to provide significant benefits in the dynamic performance under both wind and earthquake loading in a cost-effective manner.

• Journal of information and communication convergence engineering
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• 제19권1호
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• pp.22-28
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• 2021

Convolutional neural networks (CNNs) are one of the most frequently used artificial intelligence techniques. Among CNN-based applications, small and timing-sensitive applications have emerged, which must be reliable to prevent severe accidents. However, as the small and timing-sensitive systems do not have sufficient system resources, they do not possess proper error protection schemes. In this paper, we propose MATE, which is a low-cost CNN weight error correction technique. Based on the observation that all mantissa bits are not closely related to the accuracy, MATE replaces some mantissa bits in the weight with error correction codes. Therefore, MATE can provide high data protection without requiring additional memory space or modifying the memory architecture. The experimental results demonstrate that MATE retains nearly the same accuracy as the ideal error-free case on erroneous DRAM and has approximately 60% accuracy, even with extremely high bit error rates.

• Asian-Australasian Journal of Animal Sciences
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• 제28권8호
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• pp.1209-1215
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• 2015

Since lamb is a commodity, producers cannot control the price of the product they sell. Therefore, managing production costs is a necessity. We explored the study of elasticities as a tool for basing decision-making in sheep production, and aimed at investigating the composition and elasticities of lamb production costs, and their influence on the performance of the activity. A representative sheep production farm, designed in a panel meeting, was the base for calculation of lamb production cost. We then performed studies of: i) costs composition, and ii) cost elasticities for prices of inputs and for zootechnical indicators. Variable costs represented 64.15% of total cost, while 21.66% were represented by operational fixed costs, and 14.19% by the income of the factors. As for elasticities to input prices, the opportunity cost of land was the item to which production cost was more sensitive: a 1% increase in its price would cause a 0.2666% increase in lamb cost. Meanwhile, the impact of increasing any technical indicator was significantly higher than the impact of rising input prices. A 1% increase in weight at slaughter, for example, would reduce total cost in 0.91%. The greatest obstacle to economic viability of sheep production under the observed conditions is low technical efficiency. Increased production costs are more related to deficient zootechnical indexes than to high expenses.

• Asian Pacific Journal of Cancer Prevention
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• 제14권12호
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• pp.7701-7706
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• 2013

Background: In a prospective cohort study of antiemetic therapy conducted in Malaysia, a total of 94 patients received low emetogenic chemotherapy (LEC) with or without granisetron injections as the primary prophylaxis for chemotherapy-induced nausea and vomiting (CINV). This study is a retrospective cost analysis of two antiemetic regimens from the payer perspective. Materials and Methods: This cost evaluation refers to 2011, the year in which the observation was conducted. Direct costs incurred by hospitals including the drug acquisition, materials and time spent for clinical activities from prescribing to dispensing of home medications were evaluated (MYR 1=$0.32 USD). As reported to be significantly different between two regimens (96.1% vs 81.0%; p=0.017), the complete response rate of acute emesis which was defined as a patient successfully treated without any emesis episode within 24 hours after LEC was used as the main indicator for effectiveness. Results: Antiemetic drug acquisition cost per patient was 40.7 times higher for the granisetron-based regimen than for the standard regimen (MYR 64.3 vs 1.58). When both the costs for materials and clinical activities were included, the total cost per patient was 8.68 times higher for the granisetron-based regimen (MYR 73.5 vs 8.47). Considering the complete response rates, the mean cost per successfully treated patient in granisetron group was 7.31 times higher (MYR 76.5 vs 10.5). The incremental cost-effectiveness ratio (ICER) with granisetron-based regimen, relative to the standard regimen, was MYR 430.7. It was found to be most sensitive to the change of antiemetic effects of granisetron-based regimen. Conclusions: While providing a better efficacy in acute emesis control, the low incidence of acute emesis and high ICER makes use of granisetron as primary prophylaxis in LEC controversial.

• 한국건설관리학회논문집
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• 제8권6호
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• pp.178-187
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• 2007

최근 정부의 주택보급정책 강화에 따라 공공아파트 건설공사의 건축공사비에 대한 관심이 높아지고 있다. 그러나 현재 공공아파트 공사비내역 구성은 공종별 분류체계로 구성되어 있어, 공공아파트의 건축공사비를 체계적으로 예측하는 것은 현실적으로 많은 문제점을 지니고 있다. 이에 본 연구에서는 공공아파트 프로젝트 기획 및 설계단계에서 좀 더 합리적인 공사비 예측을 위해, 델파이분석(Delphi)기법을 이용하여 공공아파트 공간별 공사비분류체계를 개발하였다. 공공아파트 공간별 공사비분류체계는 공공아파트의 공간별 특성을 반영하여 주택부문, 주택외부문, 가산부문 등으로 구분하였으며, 각각의 부문을 공간별 해당 부위와 각 세부공종으로 세분화하였다. 또한 구축된 공간별 공사비분류체계에 공공아파트 공사비 내역서를 분석하여 공간별 분류체계의 실용성 및 유효성을 검증하였다.