• Structural Engineering and Mechanics
• /
• v.20 no.5
• /
• pp.527-542
• /
• 2005

The main objective of this study is to examine the accuracy of the complete quadratic combination (CQC) rule with the modal responses defined by the ordinates of the uniform hazard spectra (UHS) to evaluate the peak responses of the multi-degree-of-freedom (MDOF) systems subjected to nonstationary seismic excitations. For the probabilistic analysis of the peak responses, it is considered that the seismic excitations can be modeled using evolutionary power spectra density functions with uncertain model parameters. More specifically, a seismological model and the Kanai-Tajimi model with the boxcar or the exponential modulating functions were used to define the evolutionary power spectral density functions in this study. A set of UHS was obtained based on the probabilistic analysis of transient responses of single-degree-of-freedom systems subjected to the seismic excitations. The results of probabilistic analysis of the peak responses of MDOF systems were obtained, and compared with the peak responses calculated by using the CQC rule with the modal responses given by the UHS. The comparison seemed to indicate that the use of the CQC rule with the commonly employed correlation coefficient and the peak modal responses from the UHS could lead to significant under- or over-estimation when contributions from each of the modes are similarly significant.

• The Transactions of the Korean Institute of Electrical Engineers A
• /
• v.53 no.2
• /
• pp.87-96
• /
• 2004

This paper summarizes the research results of the load management for pole transformers done in 1997-1998 and 2000-2002. The purpose of the research is to enhance the accuracy of peak load estimation in pole transformers. We concentrated our effort on the acquisition of massive actual load data for modifying the load regression coefficients, which related to the peak load estimation of lamp-use customers, and adjusting the demand-factor coefficients, which used for the peak load prediction of motor-use customers. To enhance the load regression equations, the 264 load data acquisition devices are equipped to the sample pole transformers. For the modification of demand factor coefficients, the peak load currents are measured in each customer and pole transformer for 13 KEPCO (Korea Electric Power Corporation) distribution branch offices. Case studies for 50 sample pole transformers show that the proposed coefficients could reduce estimating error of the peak load for pole transformers, compared with the conventional one.

• Proceedings of the Korean Society for Bioinformatics Conference
• /
• 2004.11a
• /
• pp.296-306
• /
• 2004

LC/MS를 이용하여 펩타이드 혹은 단백질 같은 물질을 분석하는 실험이 급격히 늘어남에 따라 LC/MS 데이터를 자동으로 처리하는 기술에 대한 요구가 커지고 있다. 이러한 LC/MS 데이터의 자동 분석 기술에 대한 연구는 현재 활발히 진행되어 왔고, 이를 직접 구현한 여러 상용 소프트웨어들이 개발되어 있는 상태이다. LC/MS 데이터는 noise 제거, background 데이터 제거, deconvolution 알고리즘을 적용한 분자량(molecular weight) 할당 등의 작업을 거쳐 분석하게 된다. 이러한 과정을 거쳐 얻어진 분자량에 대한 데이터가 올바른 값인지 검증하는 작업이 필요하다. 본 논문에서는 이러한 검증 작업과 관련하여 Peak Clustering and Fitting(이하 PC&F)에 대한 알고리즘을 제안한다. PC&F은 peak 데이터들이 지니고 있는 속성에 대한 Mahalanobis distance를 이용하여 peak 데이터를 각 retention time에 따라 clustering 분석을 하는 작업이다. 본 논문에서 제안하는 PC&F 알고리즘을 Microsoft Visual C++ 6.0 MFC 환경에서 직접 개발한 소프트웨어(PeakClusterFitLCMS)로 실험하였다. 실험결과 PC&F 작업을 통해 동일한 구성물질로부터 발생한 peak 데이터를 모아서 보다 신뢰할 수 있는 분자량을 구할 수 있었고, 구성물질에 의해 발생되지 않은 noise peak 데이터를 찾아 제거시킬 수 있음을 확인할 수 있었다.

• Journal of the Korean Society of Physical Medicine
• /
• v.13 no.1
• /
• pp.147-154
• /
• 2018

PURPOSE: This study examined the ability of experimental socks combined with a functional insole to reduce plantar foot pressure in healthy subjects. METHODS: The study enrolled 15 subjects. An in-shoe measurement device was used to measure the peak plantar pressure while walking. The peak forefoot, midfoot, and hindfoot plantar pressure data were collected under two conditions: the subjects were wearing their own socks and while they were wearing the experimental socks. The paired t-test was used to determine the differences in peak plantar pressure between the two conditions at all three positions. RESULTS: Wearing the experimental socks resulted in a significantly higher peak plantar pressure in the medial forefoot and midfoot areas than wearing one's own socks (p<.05), and also in significantly lower peak plantar pressure in the medial and lateral hindfoot (p<.05). However, there were no significant differences of peak plantar pressure between experimental and own socks in middle and lateral forefoot (p>.05). CONCLUSION: The experimental socks combined with a functional insole decreased plantar pressure in the hindfoot and supported the medial longitudinal arch. However, it is necessary to change the design and material of the forefoot area in the functional insole to prevent foot ulcer at that location in people with diabetes mellitus.

• Electrical & Electronic Materials
• /
• v.7 no.1
• /
• pp.32-41
• /
• 1994

In this study, the TSC spectroscopy has been applied to investigate the influence of structural change due to a process of curing reaction on the electrical properties of epoxy composites cured with acid-anhydride. Five TSC peaks appeared in -160-250[.deg.C]: in the low temperature region below glass transition temperature(T$\_$g/), three relaxation mode peaks due to action of side chains, substitution group or terminal groups have been observed, a peak associated with T$\_$g/, appeared in 110[.deg. C] and p peak due to ionic space charges located in 150[.deg.C]. Each peak was separated into elementary peaks by the partial polarization procedure, and the distribution of activation energy and relaxation time were analized to clearify the origin of each peak. Also, overaboundantly added hardener separated a .betha. peak near 10[.deg. C] into two peaks of .betha.$\_$1/(10.deg. C) and .betha.$\_$2/(20.deg. C) according to increasement of forming field, and the separated hardener was oxidated thermally with increasing surrounding temperatures. The expansion of the free volume need in molecular motion and the reduction of the structural packing density through thermal oxidation process increased TSC between .alpha. peak and .betha. peak and decreased T$\_$g/.

• Journal of Korean Society of Water and Wastewater
• /
• v.30 no.3
• /
• pp.225-231
• /
• 2016

Peak load rate(i.e., maximum daily flow/average daily flow) has not been considered for industrial water demand planning in Korea to date, while area unit method based on average daily flow has been applied to decide capacity of industrial water treatment plants(WTPs). Designers of industrial WTPs has assumed that peak load would not exist if operation rate of factories in industrial sites were close to 100%. However, peak load rates were calculated as 1.10~2.53 based on daily water flow from 2009 to 2014 for 9 industrial WTPs which have been operated more than 9 years(9-38 years). Furthermore, average operation rates of 9 industrial WTPs was less than 70% which means current area unit method has tendency to overestimate water demand. Therefore, it is not reasonable to consider peak load for the calculation of water demand under current area unit method application to prevent overestimation. However, for the precise future industrial water demand calculation more precise data gathering for average daily flow and consideration of peak load rate are recommended.

• International Journal of High-Rise Buildings
• /
• v.2 no.3
• /
• pp.229-244
• /
• 2013

Twenty six pressure models of high rise buildings with various cross-sections including twisted models were tested in a boundary layer wind tunnel. The cross-sections were triangular, square, pentagon, hexagon, octagon, dodecagon, circular, and clover. This study investigates variations in peak pressures, and effects of various cross-sections and twist angles on peak pressures. To study the effects of various configurations and twist angles on peak pressures in detail, maximum positive and minimum negative peak pressures at each measurement point of the building for all wind directions are presented and discussed. The results show that peak pressures greatly depend on building cross-section and twist angle.

• Nuclear Engineering and Technology
• /
• v.6 no.1
• /
• pp.3-8
• /
• 1974

The annealing of natural beryl powder used for the thermoluminescent dosimetry was investigated in order to eliminate effect of previous exposure. Through the glow curve analysis, the optimal annealing treatment was found to be one hour annealing at 145$0^{\circ}C$, but annealing for one hour at 55$0^{\circ}C$ was sufficient for reuse of natural beryl powder. There are two distinguished glow peaks at $65^{\circ}C$ and 20$0^{\circ}C$ of heating temperature during readout process. The $65^{\circ}C$ glow peak fades away rapidly, but the 20$0^{\circ}C$ glow peak remains very stable. It is, therefore, quite feasible to use the 20$0^{\circ}C$ glow peak for thermoluminescent dosimetry.

• Korean Journal of Microbiology
• /
• v.16 no.1
• /
• pp.30-40
• /
• 1978

Detergent soluble fractions were obtained from T. ferrooxidans ATCC 13598 and the T. thiooxidans ATCC 8085 which were treated with 3% of Tween 20. The detergent soluble antigen(crude antigen) fractions of the T.ferrooxidans and the T.thiooxidans were subjected to hydroxyapatite. In the case of T.thiooxidans, further purification was carried out on the DEAE-cellulose column chromatography. The antigen fractions, such as the hydroxyapatite peak-1(Tf, HA-1) and peak-2 from T.ferrooxidans(Tf. HA-2) and hydroxyapatite peak-1(Tt, HA-1), DEAE-cellulose peak-1(Tt, DP-1) and peak-2(Tt, DP-2) from T. thiooxidans wre compared each other with the homologous and the heterologous and the heterologous antisera against to the Thiobacillus species. The hydroxyapatite peak-2 fraction from the T.ferrooxidans(Tf, HA-2) and DEAE-cellulose peak-2 fraction from the T.thiooxidans(Tt, DP-2) were represented the type-specific immuno-reactivities between the T.ferrooxidans and the T.thiooxidans on the several sets of double gel diffusioin analysis. The type-specific antigen fractions from both of the baceteria were mainly composed of protein with entierly different electrophoretic mobility on the SDS-polyacrylamide gel electrophoresis. However, the PAS positive banding patterns on the electrophorogram showed wide range of common antigenic properties in the T. ferrooxidans and the T.thiooxidans, respectively.

• Journal of ILASS-Korea
• /
• v.21 no.3
• /
• pp.155-161
• /
• 2016

Injected fuel pressure waves of a common rail injector with various current profiles supplied to the injecor were measured using Bosch method. In order to drive the common rail injector, the current in the solenoid should be controlled using what is known as a peak and hold pattern, which consists of a high current level with a short time duration (peak) in the first step and a low current level with a long time duration (hold) in the subsequent step. The current profile can be shaped by swithcing an injector driving power source with the peak and hold waves. The capture, compare and PWM (CCP) pin in the microprocessor was used to generate the combined peak and hold waves. The PWM square wave generated from the CCP pin has a duty ratio of 100% for the peak current and 10% or 30% for the hold pattern. Five patterns of the current profile were generated by combining the peak and hold wave. The common rail pressure is controlled at 75, 100, and 130 MPa. As the fuel rail pressure increases, the variations of the measured fuel injection pressure wave according to the current profiles decrease.