• Title/Summary/Keyword: Alleviation-time

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Study on the Personal Air-Conditioning System Considering Human Thermal Adaptation (인간의 열적 적응성을 고려한 퍼스널 공조시스템의 개발)

  • 송두삼
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.15 no.6
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    • pp.524-532
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    • 2003
  • In this paper, a personal air-conditioning system considering the human thermal adaptability is analyzed. Although the conventional personal air-conditioner was proofed to be satisfactory in providing for the thermal comfort, it is being questioned on the term of its energy efficiency. Therefore, it is important and urgent to develop new types of personal air-conditioning system with sustainable control strategy that can ensure energy saving and thermal comfort simultaneously. In this study, we first examined the problems of the conventional personal air-conditioning system with field interview and laboratory experiment in terms of usage, management and thermal comfort, and proposed the energy-saving personal air-conditioning system considering the human thermal adaptation. Then a laboratory experiment was performed to analyze the characteristics of the human thermal comfort under severe indoor thermal conditions, which were controlled using a new personal air-conditioning unit designed according to the proposal. The results help to illustrate the alleviation effect of the new personal air-conditioning system, and indicate that the thermal alleviation time is useful to maintain the thermal comfort with efficient usage of energy.

Design of a Variable Structure Controller having Chattering Alleviation Characteristics for the Speed Control of Sinusoidal type Brushless DC Motor (정현파형 브러시리스 직류전동기의 속도 제어를 위한 채터링 저감 특성을 갖는 가변구조 제어기 설계)

  • 김세일;최중경;박승엽
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.805-808
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    • 1999
  • In this paper, a chattering alleviation ISM speed controller for the sinusoidal type BIDC motor is designed. Dead Zone function is proposed to change the chattering occurring in the transient state form high frequency to low frequency and time-varying gains are applied for the control input to eliminate the steady state excessive chattering in the conventional ISM. The proposed Dead Zone function represents the sliding layer composed of two switching surfaces and if a state vector exists in this layer, the chattering don’t occur. Simulation and experimental results confirm the useful effects of the above algorithm.

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Enhanced Germination & Initial Seedling Development by Liquid Phase Ozonation of Plant Seeds (식물종자의 액상오존처리에 의한 종자 발아 및 초기 성장 증진)

  • Yang, Heekyung;Jeong, Yuna;Choi, Wonchul;Bae, Bumhan
    • Journal of Soil and Groundwater Environment
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    • v.24 no.5
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    • pp.1-10
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    • 2019
  • The effects of liquid phase ozonation on seed dormant alleviation and subsequent seedling growth were studied using two plant seeds of Indian jointvetch (Aeschynomene indica L.) and Indian mallow (Abutilon avicennae Gaertn.). At a constant ozone concentration ($80g/m^3$), contact time varied from 10 to 60 min with 10 min interval. Germination rate, root length, and specific root length were compared after 3-day incubation on gel-medium. The germination rate increased significantly (p<0.05) in the 50 min treatment of Indian mallow by 30% compared to the control. Enhanced root elongation was observed in the seeds of 30 min treatment of Indian jointvetch and 30~50 min treatment of Indian mallow. Specific root length, an indicator of environmental change, did not show significant changes, suggesting the level of ozone treatment has no adverse effect on seedling development. The results indicate that liquid phase seed ozonation can be an effective on-site germination alleviation method in the application of phytoremediation.

Study on a case of improvement of depression using Ortho-Cellular Nutrition Therapy (OCNT) (세포교정영양요법(OCNT)을 이용한 우울증 개선 사례 연구)

  • Minho Baek
    • CELLMED
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    • v.14 no.3
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    • pp.68.1-68.4
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    • 2024
  • Objective: Study on a case of improvement of depression through the use of OCNT Methods: OCNT was implemented due to depression that lasted over prolonged period time on a 59-year old Korean female. Results: Depression gradually improved a little by little following the implementation of OCNT and symptoms improved eventually to the extent of enabling the patient to engage in internal and external activities. Conclusion: Application of OCNT to those suffering from depression can be helpful in alleviation of symptoms.

A Study on Formation and Dissolution of Ownership Restriction System within Newspaper Act (신문법 내 소유규제 제도의 형성과 해체에 관한 연구)

  • Lee, Yong-Sung
    • Korean journal of communication and information
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    • v.56
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    • pp.71-85
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    • 2011
  • This thesis reviews the process in which the regulation systems against ownership concentration of newspapers established with the opportunity of legislation of the periodical act in 1987 was reinforced as they were all amended to the newspaper act in 2005 and as they were again amended in 2009 it came to confront crisis in the aspect of press law legislation history. The regulation systems against ownership concentration of newspapers established based on the principle of legality of newspaper function in the Clause 3, the Article 21 of Constitution was reinforced as the newspaper act in 2005 and in 2006 they began to shrink following the Constitution Court decision against newspaper act. As newspaper act and broadcast act are revised in 2009, regulation against combining the management of newspapers with broadcast and regulation against owning multiple number of newspapers came not to exist. Because in this process, the opposition party also allowed limited cross-ownership of newspaper and broadcast, it can be said that the system of newspaper ownership regulation confronted the crisis of dissolution. The instruction of regulation alleviation in a short period of time in spite of the fact that regulation alleviation which allows cross-ownership of newspaper and broadcast is the matter of policy that should be decided after long-term review of the change of media environment and the progress of the power of domination of public opinion is dangerous. Newspapers are strong media with terrestrial broadcast in formation of public opinion on politics. It's because it is difficult to ignore the worry that the power of domination of public opinion of the newspapers which are in oligopoly of newspaper public opinion market can be spreaded to the territory of report broadcast. From the point of view that there is probability for democracy to be ultimately threatened due to the shrink of political Darwinism caused by concentration of media ownership, the alleviation of ownership concentration of newspapers should have premise of long-term social discussion.

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Changes in Rheological Properties of Neungee(Sarcodon aspratus) during Dehydration (능이버섯의 건조과정 중 물성의 변화)

  • 우관식;정헌상;이희봉;최원석;이준수
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.7
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    • pp.1230-1236
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    • 2004
  • This study was conducted to investigate the changes in physical properties of the Neungee (Sarcodon aspratus) during dehydration and rehydration. The drying of the sample was completed within 4 hours at 5$0^{\circ}C$ with the air velocity of 1.5 m/s. The reduction in the thickness of the sample were two-fold compared with those in the surface area of the sample. During the drying period, the values of compression distance, break down, deformation rate, distortion, alleviation rate and softness decreased, whereas the values of hardness and alleviation time increased. However, the values of surrender were not changed. The color of the sample during the drying was changed to black with decreased L, a, and b values. The rehydration rate increased rapidly during first 60 min and remained constant after that. The recovery ratio after rehydration of the dried sample was about 30% and the rheological properties recovered about 44%.

Design of a Integral Sliding Mode Speed Controller having Chattering Alleviation Characteristics for the Sinusoidal type Brushless DC Motor (채터링 저감특성을 갖는 정현파형 브러시리스 직류전동기 (BLDC Motor)의 적분 슬라이딩 모드 속도제어기 설계)

  • Kim, Sei-Il;Choi, Jung-Keyng;Park, Seung-Yub
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.38 no.2
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    • pp.1-11
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    • 2001
  • In this paper, a chattering alleviation VSS controller for the sinusoidal type BLDC motor is designed. Dead Zone function is proposed to change the chattering occurring in the transient state from high frequency to low frequency and time varying gains arc applied for the control input to eliminate the steady state excessive chattering in the conventional ISM. The proposed Dead Zone function represents the sliding layer composed of two switching surfaces and if a state vector exists in this layer, the chattering don't occur. Simulation and experimental results confirm the useful effects of the above algorithm.

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The Effects of Visual and Auditory Feedback on Pain Reduce (시각과 청각되먹임이 통증감소에 미치는 영향)

  • Bae, Young-Sook;Kim, Soon-Hoe;Min, Kyung-Ok
    • Journal of Korean Physical Therapy Science
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    • v.9 no.1
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    • pp.1-8
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    • 2002
  • This study set out to investigate what kind of effects the consistent visual stimuli and verbal and non verbal auditory stimuli have on pain alleviation, as well as to see the influence of joint application of visual and auditory stimuli at the same time on pain alleviation, according to lightness of 50lux and 200lux, ultimately providing basic data in setting up an environment in case of treating pain. The subject were comprised of 30 male and female adults with pain in the neck and back area. The subject were treated in their pain area with Transcutaneous Electrical Nerve Stimulator(TENS) 100HZ for 20 minutes in the research set where each visual, auditory, and joint visual and auditory stimuli was given. For analysis methods, Visual Analogue Scale(VAS) and McGill Pain Questionnaire were adopted to see the changes before and after treatment, and the electrocardiogram, systolic and diastolic pressure, number of heart rate and breathing frequence and endorphin were compared and analyzed using the Wilcoxon singed-rank test. And The Kreskal-walllis test was used to compare the two subgroups from each group. Wilcoxon singed-rank test and the Kreskal-walllis test was used to compare the two subgroups from each group. The results were as follows: 1. The group of 50lux and 200lux were compared given varying degrees of visual stimuli. The group of 200lux showed more reduction in pain points, average systolic and diastolic pressure and average endorphin. 2. The group of verbal and non verbal were compared given varying degrees of auditory stimuli. The group of non-verbal showed more reduction in average systolic and diastolic pressure. 3. The group of 200lux+verbal and 200lux+non verbal were compared given varying degrees of joint visual and auditory stimuli. There was found a statistical significance(p<0.05) in endorphin between the two groups, with more endorphin reduction for 200lux+non verbal group. And there was a statistically significant reduction in VAS and McGill before and after the treatment between the two groups.

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Ramp Metering under Exogenous Disturbance using Discrete-Time Sliding Mode Control (이산 슬라이딩모드 제어를 이용한 램프 미터링 제어)

  • Jin, Xin;Chwa, Dongkyoung;Hong, Young-Dae
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.65 no.12
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    • pp.2046-2052
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    • 2016
  • Ramp metering is one of the most efficient and widely used control methods for an intelligent transportation management system on a freeway. Its objective is to control and upgrade freeway traffic by regulating the number of vehicles entering the freeway entrance ramp, in such a way that not only the alleviation of the congestion but also the smoothing of the traffic flow around the desired density level can be achieved for the maintenance of the maximum mainline throughput. When the cycle of the signal detection is larger than that of the system process, the density tracking problem needs to be considered in the form of the discrete-time system. Therefore, a discrete-time sliding mode control method is proposed for the ramp metering problem in the presence of both input constraint in the on-ramp and exogenous disturbance in the off-ramp considering the random behavior of the driver. Simulations were performed using a validated second-order macroscopic traffic flow model in Matlab environment and the simulation results indicate that proposed control method can achieve better performance than previously well-known ALINEA strategy in the sense that mainstream flow throughput is maximized and congestion is alleviated even in the presence of input constraint and exogenous disturbance.

Identification of Aerodynamic Model CFD-Based for Gust Response Analysis

  • Nie, Xueyuan;Yang, Guowei
    • International Journal of Aerospace System Engineering
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    • v.2 no.1
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    • pp.43-46
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    • 2015
  • Aeroelastic gust response analysis plays an important role in design of aircrafts. For gust response analysis, frequency domain aerodynamics method has been typically used with generalized aerodynamic influence coefficient matrices at various reduced frequencies. However, it cannot be applied to the aeroservoelastic analysis, such as gust alleviation control. Time-domain state space (SS) models must be built. It attacks little attention that gust response analysis relies on continuous gust time-domain input signal in terms of its PSD function. The aim the current study is to provide a reduced-order modeling (ROM) method based on CFD to model gust responses for continuous gust responses for continuou gust inputs in time domain. The paper analyzed the gust response of AGARD445.6 wing subjected to the Dryden gust with ROMs and compared the difference between the rigid structure and elastic one. The results demonstrate that structure elastic effect effect should be considered in the design of aircraft.