• Title/Summary/Keyword: Time-scaling

Search Result 682, Processing Time 0.027 seconds

The Design of IMC-PID Controller Considering a Phase Scaling Factor (위상 조절 인자를 고려한 IMC-PID 제어기의 설계)

  • Kim, Chang-Hyun;Lim, Dong-Kyun
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.57 no.9
    • /
    • pp.1618-1623
    • /
    • 2008
  • In this paper, a new design method for IMC-PID that adds a phase scaling factor of system identifications to the standard IMC-PID controller as a control parameter is proposed. Based on analytically derived frequency properties such as gain and phase margins, this tuning rule is an optimal control method determining the optimum values of controlling factors to minimize the cost function, integral error criterion of the step response in time domain, in the constraints of design parameters to guarantee qualified frequency design specifications. The proposed controller improves existing single-parameter design methods of IMC-PID in the inflexibility problem to be able to consider various design specifications. Its effectiveness is examined by a simulation example, where a comparison of the performances obtained with the proposed tuning rule and with other common tuning rules is shown.

Application of Multidimensional Scaling Method for E-Commerce Personalized Recommendation (전자상거래 개인화 추천을 위한 다차원척도법의 활용)

  • Kim Jong U;Yu Gi Hyeon;Easley Robert F.
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 2002.05a
    • /
    • pp.93-97
    • /
    • 2002
  • In this paper, we propose personalized recommendation techniques based on multidimensional scaling (MDS) method for Business to Consumer Electronic Commerce. The multidimensional scaling method is traditionally used in marketing domain for analyzing customers' perceptional differences about brands and products. In this study, using purchase history data, customers in learning dataset are assigned to specific product categories, and after then using MDS a positioning map is generated to map product categories and alternative advertisements. The positioning map will be used to select personalized advertisement in real time situation. In this paper, we suggest the detail design of personalized recommendation method using MDS and compare with other approaches (random approach, collaborative filtering, and TOP3 approach)

  • PDF

Adaptive Online Voltage Scaling Scheme Based on the Nash Bargaining Solution

  • Kim, Sung-Wook
    • ETRI Journal
    • /
    • v.33 no.3
    • /
    • pp.407-414
    • /
    • 2011
  • In an effort to reduce energy consumption, research into adaptive power management in real-time systems has become widespread. In this paper, a novel dynamic voltage scaling scheme is proposed for multiprocessor systems. Based on the concept of the Nash bargaining solution, a processor's clock speed and supply voltage are dynamically adjusted to satisfy these conflicting performance metrics. In addition, the proposed algorithm is implemented to react adaptively to the current system conditions by using an adaptive online approach. Simulation results clearly indicate that the superior performance of the proposed scheme can strike the appropriate performance balance between contradictory requirements.

The Effectiveness of Subgingival Scaling and Root Planing via Closed Approach in Calculus Removal (치은연하 치석제거 및 치근활택술의 치석제거 효과에 대한 임상적 연구)

  • Kim, Sung-Jo
    • Journal of Periodontal and Implant Science
    • /
    • v.28 no.2
    • /
    • pp.371-376
    • /
    • 1998
  • This study presents an evaluation of the effectiveness of nonsurgical subgingival scaling and root planing related to initial pocket depth, type of teeth, and individual root surfaces. A total of 110 teeth designated for periodontal surgery in 67 patients with marginal periodontitis were selected and received thorough scaling and root planing with standard rigid Gracey curettes. After a healing period of 4 to 8 weeks, residual calculus was assessed at the time of periodontal surgery following the reflection of mucoperiosteal flap. The results demonstrated a high correlation between the percentage of residual calculus and initial pocket depth. It was further noted that tooth type and involved root surface also influenced the rate of calculus remnant. The results of this study suggest that complete removal of subgingival calculus utilizing conventional instrumentation via closed approach is rare.

  • PDF

Scaling Analysis of Thermal Hydraulics Phenomena in the Nuclear Reactor Vessel Downcomer during the Reflood Phase of LBLOCA (대형냉각재 상실사고 재관수 기간 동안, 차세대 원자로 강수부 내의 열수력 현상 모의를 위한 실험장치 척도해석)

  • Yun, B.J.;Song, C.H.;Kwon, T.S.;Euh, D.J.;Chu, I.C.;Yoon, Y.J.
    • Proceedings of the KSME Conference
    • /
    • 2001.06d
    • /
    • pp.821-827
    • /
    • 2001
  • As one of the advanced design features of the Korea next generation reactor, direct vessel injection (DVI) system is being considered instead of conventional cold leg injection (CLl) system. It is known that the DVI system greatly enhances the reliability of the emergency core cooling (ECC) system. However, there is still a dispute on its performance in terms of water delivery to the reactor core during the reflood period of a large-break loss-of-coolant accident (LOCA). Thus, experimental validation is under progress. In this paper, a new scaling method, using time and velocity reduced linear scaling law, is suggested for the design of a scaled-down experimental facility to investigate the direct ECC bypass phenomena in PWR downcomer.

  • PDF

하악 매복지치의 예방적 발거 후 구취의 평가

  • Sim, Jeong-Hwan;Kim, Yeong-Gyun;Choe, Yong-Geun
    • The Journal of the Korean dental association
    • /
    • v.41 no.1 s.404
    • /
    • pp.42-47
    • /
    • 2003
  • Dental professions recommend that mandibular impacted third molar be extracted for the prevention of osteomyelities crneoplasm or for the treatment of halitosis. Even the possibility of emergence of unexpected halitosis after the preventive extraction exists, there are few studies describing the unexpected halitosis. This study intended to measure the emergence of halitosis after extraction of mandibular impacted third molar. Thirty-eight patients who visited Daejin Medical Center participated in this study. Halitosis was objectively measured using Halimeter in 3 intervals-before, after I day, after 7 days. Third factors, scaling and gender, which may influence the halitosis were analyzed with stratification. This study finds that in general halitosis decreased after 1 day but increased after 7 days. Scaling was helpful in decreasing halitosis and women have less severe halitosis than men. The effects of time interval(p<0.05), gender(p=0.836), and scaling(p=0.7929) on the severity of halitosis were not statistically significant. However, since this study's patients are neither a representative sample nor a random sample, all data interpretation was focused on clinical significance instead of conventional statistical significance. Clinical significance of this study's findings are: 1) scaling should be conducted in advance, 2) men should be notified of the higher possibility of halitosis.

  • PDF

Design and implementation of pre-scaling look-up table for very-high radix divider (고속나눗셈 연산기를 위한 영역변환상수 검색테이블의 설계 및 구현)

  • Lee, Byeong-Seok;Lee, Jeong-A
    • Journal of IKEEE
    • /
    • v.3 no.2 s.5
    • /
    • pp.276-284
    • /
    • 1999
  • In this paper, we propose a new technique which allows to store the pre-scaling constants directly in a table thus eliminating the cycle for computing pre-scaling constants. Especially we analyzed the range of pre-scalingconstants and rearranged them in a carry-save form using two look-up tables so that the size of the tables can be reduced significantly. The resulting scheme is compared with the previously developed method and shown to be effective with respect to area and time to implement the high-radix divider.

  • PDF

A novel clustering method for examining and analyzing the intellectual structure of a scholarly field (지적 구조 분석을 위한 새로운 클러스터링 기법에 관한 연구)

  • Lee, Jae-Yun
    • Journal of the Korean Society for information Management
    • /
    • v.23 no.4 s.62
    • /
    • pp.215-231
    • /
    • 2006
  • Recently there are many bibliometric studies attempting to utilize Pathfinder networks(PFNets) for examining and analyzing the intellectual structure of a scholarly field. Pathfinder network scaling has many advantages over traditional multidimensional scaling, including its ability to represent local details as well as global intellectual structure. However there are some limitations in PFNets including very high time complexity. And Pathfinder network scaling cannot be combined with cluster analysis, which has been combined well with traditional multidimensional scaling method. In this paper, a new method named as Parallel Nearest Neighbor Clustering (PNNC) are proposed for complementing those weak points of PFNets. Comparing the clustering performance with traditional hierarchical agglomerative clustering methods shows that PNNC is not only a complement to PFNets but also a fast and powerful clustering method for organizing informations.

Scaling Behavior of Manufacturing Industry Worker (제조업 근로자의 스켈링에 대한 행태와 관련요인)

  • Jung Eun Kyung;Nam Yong Ok;Jin Seok Ho;Seo Nam Deuk;Kim Jung Sock;Nam Chul Hyun
    • Korean Journal of Health Education and Promotion
    • /
    • v.22 no.1
    • /
    • pp.1-16
    • /
    • 2005
  • The study was performed to examine the scaling behavior about dental health. The subjects of this study were 700 workers selected in Daegu. This survey was carried out during 2003. 7. 15 - 2003. 7. 31. The results of this study can be summarized as follows. 1. Distribution of respondent's class was male of $53.5\%, female of $46.2\%, and 30's age of $36.2\%, 20's age of $28.2\%. Concerning about dental health was appeared that female was higher rate than male. also, difference was related in their age, working department and residence. 2. In case of no experience to scaling for past 3 years was appeared that male of $67.6\% was higher rate than female of $56.8\%. The frequency of treat scaling was appeared that $46.2\% of the subjects was treated scaling per year. 3. The root cause of no treatment by regular was appeared that 'high expensive' was most high with $38.0\% and 2nd, 'didn't felt importance' was $24.2\%, 3rd 'lack of spare time' was $20.7\%, the last ranking 'only be frightened' was $14.3\%. 4. Method of learning knowledge about scaling was appeared that male and female were similar with their method of it. knowledge level of scaling was learned by internet were higher in worker of 20's age than any other age. also, other difference was related in school career and residence. Opinion about necessity of scaling answer which need or surely need were similar to male of $67.1\% and female of $72.6\%. 5. As for knowledge of scaling was appeared that male of $94.3\% and female of $87.1\% had corrective knowledge. The right answer was significantly different by ages, school career, working department and residence.

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
    • /
    • v.22 no.5
    • /
    • pp.59-67
    • /
    • 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.