• Title/Summary/Keyword: time scaling

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Comparison of 1-g and Centrifuge Model Tests for Similitude Laws (상사법칙 검증을 위한 1-g 모형실험과 원심모형실험의 비교 연구)

  • Kim Sung-Ryul;Hwang Jae-Ik;Kim Myoung-Mo;Ko Hon-Yim
    • Journal of the Korean Geotechnical Society
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    • v.22 no.5
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    • pp.59-67
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    • 2006
  • The centrifuge and 1-g shaking table tests were performed simultaneously to compare the dynamic behaviors of loose sands of the same geotechnical properties. The prototype soils were 10 m thick liquefiable loose sands. The geometric scaling factors were 20 for 1-g and 40 for centrifuge tests. The excess pore pressure, surface settlement, and acceleration in the soil were measured at the same locations in the 1-g and centrifuge tests. The total excess pore pressure from development to dissipation was measured. In the centrifuge test, viscous fluid was used as the pore water to eliminate the time scaling difference between dynamic time and dissipation time. In the 1-g tests, the steady state concept was applied to determine the unit weight of the model soil, and two different time scaling factors were applied for the dynamic time and the dissipation time. It is concluded that the 1-g tests can simulate the excess pore pressure of the prototype soil if the permeability of the model soil is small enough to prevent dissipation of excess pore pressure during shaking and the dissipation time scaling factor is properly determined.

Constant Time Algorithms for Region Expansion and Scaling of Linear Quadtrees on RMESH (RMESH 구조에서 선형 사진트리의 영역 확장과 스케일링을 위한 상수시간 알고리즘)

  • Woo, Jin-Woon
    • The KIPS Transactions:PartA
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    • v.11A no.3
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    • pp.173-180
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    • 2004
  • Quadtree, which 11 a hierarchical data structure, is a very important data structure to represent images. The linear quadtree representation as a way to store a quadtree is efficient to save space compared with other representations. Therefore, it has been widely studied to develop efficient algorithms to execute operations related to quadtrees. The region expansion is an operation to expand images by a given distance and the scaling If an operation to scale images by a given scale factor. In this paper, we present algorithms to perform the region expansion and scaling of images represented by quadtrees, using three-dimensional n${\times}$n${\times}$n processors on RMESH(Reconfigurable MESH). These algorithms have constant time complexities by using efficient basic operations to route the locational codes of quadtree on the hierarchical structure of n${\times}$n${\times}$n RMESH.

Calculation of a First-In-Man Dose of 7-O-Succinyl Macrolactin A Based on Allometric Scaling of Data from Mice, Rats, and Dogs

  • Noh, Keumhan;Kang, Wonku
    • Biomolecules & Therapeutics
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    • v.25 no.6
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    • pp.648-658
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    • 2017
  • 7-O-Succinyl macrolactin A (SMA) exerts several pharmacological effects including anti-bacterial, anti-inflammation, and anti-cancer activities. Recently, SMA has been extensively evaluated as an anti-cancer drug. Thus, the objectives of the present study were to characterise the pharmacokinetics of SMA via both non-compartmental and compartmental analysis in mice, rats, and dogs, and to derive an appropriate first-in-man dose based on allometric scaling of the animal data. The time courses of plasma SMA concentrations after intravenous administration to rats and dogs were analysed retrospectively, as were data collected after intraperitoneal SMA injection in mice. Pharmacokinetic parameters were estimated via both noncompartmental and compartmental analysis, and were correlated with body weight and/or the potential maximum life-span. The clearance and distribution volume of SMA in humans were predicted, and a first-in-man dose proposed. A two-compartment model best described the time courses of SMA plasma concentrations after a saturation elimination process was applied to fit the dataset obtained from rats. Incorporation of the maximum potential life-span during allometric scaling was required to improve the estimation of human clearance. The SMA clearance and the distribution volume in the steady state, in a 70-kg adult male, were estimated to be 30.6 L/h and 19.5 L, respectively. To meet the area under the curve (AUC) required for anti-tumour activity, a dose of 100 mg (~1.5 mg/kg) was finally proposed as the first dose for a 70-kg human. Although toxicological profiles derived from non-clinical studies must be considered before any final decision is made, our work will facilitate clinical studies on SMA.

Robust Finite-Time Stabilization for an Uncertain Nonlinear System (불확실한 비선형 시스템에 대한 강인 유한 시간 안정화)

  • Seo, Sang-Bo;Shin, Hyung-Bo;Seo, Jin-Heon
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.46 no.2
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    • pp.7-14
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    • 2009
  • In this paper we consider the problem of global finite-time stabilization for a class of uncertain nonlinear systems which include uncertainties. The uncertainties are time-varying disturbances or parameters belong to a known compact set. The proposed design method is based on backstepping and dynamic exponent scaling using an augmented dynamics, from which, a dynamic smooth feedback controller is derived. The finite-time stability of the closed-loop system and boundedness of the controller are preyed by the finite-time Lyapunov stability theory and a new notion 'degree indicator'.

A Lock-Time Improvement for an X-Band Frequency Synthesizer Using an Active Fast-Lock Loop Filter

  • Heo, Yun-Seong;Oh, Hyun-Seok;Jeong, Hae-Chang;Yeom, Kyung-Whan
    • Journal of electromagnetic engineering and science
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    • v.11 no.2
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    • pp.105-112
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    • 2011
  • In phase-locked frequency synthesizers, a fast-lock technique is frequently employed to overcome the trade-off between a lock-time and a spurious response. The function of fast-lock in a conventional PLL (Phased Lock Loop) IC (Integrated Circuit) is limited by a factor of 16, which is usually implemented by a scaling of charge pumper, and consequently a lock time improvement of a factor of 4 is possible using the conventional PLL IC. In this paper, we propose a novel external active fast-lock loop filter. The proposed loop filter provides, conceptually, an unlimited scaling of charge pumper current, and can overcome conventional trade-off between lock-time and spur suppression. To demonstrate the validity of our proposed loop-filter, we fabricated an X-band frequency synthesizer using the proposed loop filter. The loop filter in the synthesizer is designed to have a loop bandwidth of 100 kHz in the fast-lock mode and a loop bandwidth of 5 kHz in the normal mode, which corresponds to a charge pumper current change ratio of 400. The X-band synthesizer shows successful performance of a lock-time of below 10 ${\mu}sec$ and reference spur suppression below -64 dBc.

Comparison of different post-processing techniques in real-time forecast skill improvement

  • Jabbari, Aida;Bae, Deg-Hyo
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.150-150
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    • 2018
  • The Numerical Weather Prediction (NWP) models provide information for weather forecasts. The highly nonlinear and complex interactions in the atmosphere are simplified in meteorological models through approximations and parameterization. Therefore, the simplifications may lead to biases and errors in model results. Although the models have improved over time, the biased outputs of these models are still a matter of concern in meteorological and hydrological studies. Thus, bias removal is an essential step prior to using outputs of atmospheric models. The main idea of statistical bias correction methods is to develop a statistical relationship between modeled and observed variables over the same historical period. The Model Output Statistics (MOS) would be desirable to better match the real time forecast data with observation records. Statistical post-processing methods relate model outputs to the observed values at the sites of interest. In this study three methods are used to remove the possible biases of the real-time outputs of the Weather Research and Forecast (WRF) model in Imjin basin (North and South Korea). The post-processing techniques include the Linear Regression (LR), Linear Scaling (LS) and Power Scaling (PS) methods. The MOS techniques used in this study include three main steps: preprocessing of the historical data in training set, development of the equations, and application of the equations for the validation set. The expected results show the accuracy improvement of the real-time forecast data before and after bias correction. The comparison of the different methods will clarify the best method for the purpose of the forecast skill enhancement in a real-time case study.

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A study on the health behavior and oral health management of adults in Gumi (구미지역 성인들의 건강행위와 구강건강관리실태조사)

  • Yoon, Sung-Uk;Nam, In-Suk
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.2
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    • pp.269-282
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    • 2010
  • Objectives : The purpose of this study was to investigate attitudes toward and practice of oral health management among adults in the Gumi area. Health behavior especially drinking and smoking have been proven to affect the tissues around the teeth and increasing in importance. Thus the study set out to examine oral management according to drinking and smoking to suggest a need for education about oral health and provide basic data for oral health education. Methods : Total 226 subjects, who consist of 141 male adults and 85 female adults, in Gumi were asked to fill out a self-administered questionnaire on October 24, 2009. Their answers to the items about general characteristics, health behavior, and oral health behavior were analyzed with the SPSS WIN 12.0 program. Results : 1. As for the frequency of visiting a dental clinic(hospital) for the last year, the non-movement group recorded higher frequency than the movement group, and the drinking group also did than the non-drinking group(p<0.05). 2. As for the experience and frequency of scaling, the female subjects were higher in the experience and frequency of scaling than their male counterparts. The older they got, the more they tended to have scaling. The married respondents had more experiences of scaling than the singles, and the non-drinking group was high in the experience of scaling(p<0.05). 3. As for the number, time, and method of toothbrushing a day, more women answered they brushed teeth three times or more per day than men; those who were in their forties were the highest in terms of the roll method, and those who were in their twenties were the highest in terms of toothbrushing time. The married group and the non-smoking group answered they brushed teeth in the roll method three times or more per day in higher percentage. And the non-drinking group was high in the roll method, which was statistically significant(p<0.05). 4. As for use and kinds of auxiliary oral hygiene devices, the female respondents used them more than their male counterparts. The older they became, the more they used them. The married group, the non-smoking group, and the non-drinking group used such devices a lot. The smoking group used dental floss most, and the non-smoking group used more kinds of such devices than the smoking group, which was statistically significant(p<0.05). Conclusion : Oral diseases can be prevented by adopting healthy and right oral management behavior. Using the findings of the study, more diverse programs about actual oral health education should be activated so that people can change their bad oral management and behavior and develop a habit of the right oral management attitude.

A study on the oral health behavior of oral prophylaxis clients (스켈링 실습실 방문자의 구강건강행위에 관한 연구)

  • Jang, Gye-Won;Kang, Yong-Ju;Jeong, Mi-Kyoung
    • Journal of Korean society of Dental Hygiene
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    • v.10 no.6
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    • pp.1083-1093
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    • 2010
  • Objective : The purpose of this study was to examine the relationship of the oral health behavior of oral prophylaxis clients and some residents in a community to their simplified oral environment index. Methods : The subjects in this study were 520 people who had their teeth cleaned in the oral prophylaxis practice lab in the department of dental hygiene at J health college. A survey was conducted from March 23 to June 3, 2010, by way of the self-reported questionnaire. The data materials are analyzed by general characteristics frequency and ratio, the relationship of oral health behavior and sex, age, scaling experience, simplified oral hygiene index $x^{2}$ test analysis. Results : 1. Concerning links between gender and oral health behavior including daily toothbrushing frequency, the largest group of the respondents brushed their teeth three times a day(p<0.05). As to educational experiences on toothbrushing method and the use of oral hygiene supplies, the women had more educational experiences than the men(p<0.05). 2. Regarding connections between age and oral health behavior involving daily toothbrushing frequency, the largest number of the respondents brushed their teeth three times a day in every age group (p <0.001). As for educational experiences on toothbrushing method, those who were in their 50s and up(64.7%) learned about that, and they had more educational experiences with age(p<0.05). As for scaling experiences, the older respondents had their teeth scaled more often (p<0.001). 3. As to relationship between scaling experiences and oral health behavior, there were differences in toothbrushing frequency according to scaling experiences(p <0.05). Regarding educational experiences on toothbrushing method, those who had their teeth cleaned received more toothbrushing education(p<0.001). Concerning smoking, the nonsmokers had more experiences to get their teeth cleaned (p<0.001). 4. As for links between simplified oral environment index and oral health behavior including a time for toothbrushing, the respondents who did toothbrushing after every meal(80.4%) had good simplified oral environment indexes(p<0.05). 5. In regard to relationship between simplified oral environment index and oral health behavior, oral environment index had a positive correlation to the use of oral hygiene supplies( r=0.129**), toothbrushing time(r=0.116**) and educational experiences on toothbrushing method (r=0.099**). Smoking(r=-0.092**) had a negative correlation to that. Conclusion : The above-mentioned findings illustrate that oral health behavior is one of crucial factors to affect oral health status and oral environment care. Therefore oral prophylaxis practice lab visitors should receive education on the right toothbrushing method and the use of oral hygiene supplies to promote their oral health, and an incremental oral health care system that involves regular scaling should be introduced.

Performance Evaluation of Scaling based Dynamic Time Warping Algorithms for the Detection of Low-rate TCP Attacks (Low-rate TCP 공격 탐지를 위한 스케일링 기반 DTW 알고리즘의 성능 분석)

  • So, Won-Ho;Shim, Sang-Heon;Yoo, Kyoung-Min;Kim, Young-Chon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.44 no.3 s.357
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    • pp.33-40
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    • 2007
  • In this paper, low-rate TCP attack as one of shrew attacks is considered and the scaling based dynamic time warping (S-DTW) algorithm is introduced. The low-rate TCP attack can not be detected by the detection method for the previous flooding DoS/DDoS (Denial of Service/Distirbuted Denial of Service) attacks due to its low average traffic rate. It, however, is a periodic short burst that exploits the homogeneity of the minimum retransmission timeout (RTO) of TCP flows and then some pattern matching mechanisms have been proposed to detect it among legitimate input flows. A DTW mechanism as one of detection approaches has proposed to detect attack input stream consisting of many legitimate or attack flows, and shown a depending method as well. This approach, however, has a problem that legitimate input stream may be caught as an attack one. In addition, it is difficult to decide a threshold for separation between the legitimate and the malicious. Thus, the causes of this problem are analyzed through simulation and the scaling by maximum auto-correlation value is executed before computing the DTW. We also discuss the results on applying various scaling approaches and using standard deviation of input streams monitored.

Analysis Characteristic the Using Surface Electromyography of Head Neck and Around of Shoulder Muscles Express Scaling Working of the Dental Hygienist (치과위생사의 스켈링 작업 시 발현되는 두경부 및 견부 주위 근육들의 표면 근전도를 이용한 특성 분석)

  • Jeon, Eun-Suk;Nam, Kun-Woo;Ha, Mi-Sook
    • Journal of dental hygiene science
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    • v.12 no.4
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    • pp.437-442
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    • 2012
  • The current research examines the aching part and the muscle activity that happens during scaling practice subject to 20 dental hygienic students and therefore propose a basic data according to the working attitude of the Dental Hygienist. During the scaling we used the free EMG (BTS Inc., Milan, Italy) to measure the muscle activity, and in order to check the musculoskeletal pain area we used the Nordic-style questionnaire, and the measured research results are as following: At the moment of scaling according to posture the occurrence of the pain showed no difference among the groups elbow, back, leg, knee, ankle/foot but in the neck, shoulder, wrist/hand, waist showed a high difference in the degree of pain according to posture. Results from measuring the muscular activity according to posture, in the group that had a good posture, the trapezius and brachial muscles showed a change according to time, and in the group that had a bad posture a high muscle activity was shown in larynx, trapezius and brachial muscles. In the muscle activity, the changing aspect between the two parts, the group that fulfilled a scaling in a good posture showed a low muscle activity, but in the group that fulfilled the scaling in a bad posture the muscle activity increased excessively. Therefore we examined that when fulfilling a scaling maintaining a bad posture can help in using more effectively the activity of the muscle, in the future I think there is a need to raise the office efficiency by subjecting to dental hyginiest that are in the clinics and performing experiments.