• Title/Summary/Keyword: Time-state control form

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The Analysis of Knowledge Structure using Co-word Method in Quality Management Field (동시단어분석을 이용한 품질경영분야 지식구조 분석)

  • Park, Man-Hee
    • Journal of Korean Society for Quality Management
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    • v.44 no.2
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    • pp.389-408
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    • 2016
  • Purpose: This study was designed to analyze the behavioral change of knowledge structures and the trends of research topics in the quality management field. Methods: The network structure and knowledge structure of the words were visualized in map form using co-word analysis, cluster analysis and strategic diagram. Results: Summarizing the research results obtained in this study are as follows. First, the word network derived from co-occurrence matrix had 106 nodes and 5,314 links and its density was analyzed to 0.95. Average betweenness centrality of word network was 2.37. In addition, average closeness centrality and average eigenvector centrality of word network were 0.01. Second, by applying optimal criteria of cluster decision and K-means algorithm to word co-occurrence matrix, 106 words were grouped into seven clusters such as standard & efficiency, product design, reliability, control chart, quality model, 6 sigma, and service quality. Conclusion: According to the results of strategic diagram analysis over time, the traditional research topics of quality management field related to reliability, 6 sigma, control chart topics in the third quadrant were revealed to be declined for their study importance. Research topics related to product design and customer satisfaction were found to be an important research topic over analysis periods. Research topic related to management innovation was emerging state and the scope of research topics related to process model was extended to research topics with system performance. Research topic related to service quality located in the first quadrant was analyzed as the key research topic.

Energy Density Control for the Global Attenuation of Broadband Noise Fields (광대역 잡음의 전역 감쇠를 위한 에너지 밀도 제어)

  • Park, Young-Cheol;Yun, Jeong-Hyeon;Youn, Dae-Hee;Cha, Il-Whan
    • The Journal of the Acoustical Society of Korea
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    • v.15 no.2
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    • pp.21-32
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    • 1996
  • The performance of the energy density control algorithm for controlling a broadband noise is evaluated in a one-dimensional enclosure. To avoid noncausality problem of a control filter, which often happens in a frequency domain optimization, analyses presented in this paper are undertaken in the time domain. This approach provides the form of the causally constrained optimal controller. Numerical results are presented to predict the performance of the active noise control system, and indicate that imp개ved global attenuation of the broadband noise can be achieved by minimizing the energy density, rather than the squared pressure. It is shown that minimizing the energy density at a single location yields global attenuation results that are comparable to minimizing the potential energy. Furthermore, unlike the squared pressure control, the energy density control does not demonstrate any dependence on the error sensor location for this one-dimensional field. A practical implementation of the energy-based control algorithm is presented. Results show that the energy density control can be implemented using the two sensor technique with a tolerable margin of performance degradation.

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IMPACT OF PARENTAL PSYCHIATRIC DISORDER ON OFFSPRING'S DEPRESSION, ANXIETY, SELF CONCEPT AND PERCEPTION OF FAMILIAL RELATIONSHIP (정신과 환자 자녀의 우울, 불안, 자기 개념 그리고 가정환경의 특성에 대한 연구)

  • Lee, Jung-Bum;Cho, Soo-Churl
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.9 no.1
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    • pp.54-66
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    • 1998
  • Objectives:This study was to investigate the impact of parental psychiatric disorder on offspring's depression, anxiety, self concept, perception of familial relationship compared with offspring of normal control. In offsprings of parents with psychiatric disorder, this study explored whether their psychopathology, self concept, and perception of familial relationship were influenced by parent’s sex, onset time of parent’s psychiatric disorder and parent’s psychiatric diagnosis. Methods:52 offsprings aged 10-18 years of 39 psychiatric outpatient were surveyed from June, 1997 to April, 1998 and completed several questionnaaire, including Korean from of the Family Environment Scale, Korean form of the State-Trait Anxiety Inventory for Children, Korean form of Kovac’s Children’s Depression Inventory, and Korean form of Piers-Harris Children’s Self-Concept Scale. Their score was compared with offsprings’ of normals. In offsprings of parents with psychiatric disorder, they were compared according to parent’s sex, onset time of parent's psychiatric disorder and parent’s psychiatric diagnosis. Results:The results were as follows:1) Offsprings of parents with psychiatric disorder reported higher level of state anxiety and lower level of the FES expressive subscale than offsprings of normals(p<0.05). But they reported higher level of PHCSCS intellectual & school status subscale and popularity subscale than normals(p<0.05). 2) There were no differences in anxiety, depression, self concept, and perception of familial relationship between patient’s sex. 3) Offsprings less than 3 years old when parent’s psychiatric disorder had developed showed higher level of trait anxiety and lower level of FES control subscale than offsprings more than 3 years old (p<0.05). 4) There were no diferences in anxiety, depression, self concept, and perception of familial relationship between patient’ diagnostic groups(schizophrenia spectrum disorder-mood disoderneurosis). Conclusion:The finding indicated that self reported scale of anxiety and depression showed no significant difference between offsprings of psychiatric patients and offsprings of normals. In offsprings of parents with psychiatric disorder, parent’s sex and psychiatiric diagnosis had no influence on offspring’s psychopathology. But the offspring’s age(before 3 years old) when the parent’s psychiatriric disorder developed had influence on higher level of offspring’s trait anxiety. For further high risk group study, direct interview and evaluation of parent-child agreement or teacher-child agreement will be needed in longitudinal study.

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People's heart-and-mind and the righteous principle in the hostile of circumstances / focusing on Yeheon's Record of Taking Refuge (난중(亂中)의 인심(人心)과 의리(義理) - 여헌(旅軒) 장현광(張顯光)의 『용사일기(龍蛇日記)』를 중심으로 -)

  • Jeon, Byoung-Ok
    • (The)Study of the Eastern Classic
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    • no.57
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    • pp.9-40
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    • 2014
  • This article focuses on Yeheon's consideration and solution for the hostile of social circumstances during the time of the Japanese invasions. Yeheon thought that the Chosun dynasty must have faced such disorder before the war happened. People including the king and his subjects did not live their life according to the righteous principle, and the state was not under control in a way that it should accomplish the Dao. Yeheon thought that the Japanese invasion, which is more like a flood or certain disasters, was not primarily responsible for the harshest of environments. Yeheon paid his attention to the fact that even after the Japanese invasions ended, people were still in disorder losing their mind-and-heart. People's mind-and-heart became that of animals because of starvation and disease. This is because the government made people trapped in a difficult situation by forcing them to prepare for military operations, rather than taking care of them. As a result, in Yeheon's view, the main cause of the social disorder was people's lack of mind-and-heart, which brought about their actions of brutality like those of animals. Although Yeheon himself did not form righteous armies, he instead suggested a right path to overcome and solve the social disorder by describing and analyzing in detail the reality of the war as well as the problems of policies. In particular, Yeheon studied the Zhou yi at the time because understanding the principle of fortune and misfortune, as well as the rise and fall of a state, could give a proper solution to the social turmoil of his times. In Yeheon's eyes, the most important thing to do in the time of people's losing mind-and-heart was to follow li and accomplish the Dao in their daily life. And this was what he, as a gentleman, should do. Yeheon thought that in spite of the harshest of environments, one can still preserve one's grace and dignity, which would overcome one's adversity. This gives us the following questions: should one put aside one's grace and dignity to overcome wartime perils? Or in so doing, one should face more severe time after a short period of peace and stability? These questions concern the relationship between one's morality and the state's responsibility, and what is the right way of doing one's duty to the state is the main philosophical subject in this article.

The Controller Design for Lane Following with 3-Degree of Freedom Vehicle Dynamics (3자유도 차량모델을 이용한 차선추종 µ 제어기 설계)

  • Ji, Sang-Won;Lim, Tae-Woo;You, Sam-Sang;Kim, Hwan-Seong
    • Journal of Power System Engineering
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    • v.17 no.3
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    • pp.72-81
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    • 2013
  • Many articles have been published about a 2-degree of freedom model that includes the lateral and yaw motions for controller synthesis in intelligent transport system applications. In this paper, a 3-degree of freedom linear model that includes the roll motion is developed to design a robust steering controller for lane following maneuvers using ${\mu}$-synthesis. This linear perturbed system includes a set of parametric uncertainties in cornering stiffness and unmodelled dynamics in steering actuators. The state-space model with parametric uncertainties is represented in linear fractional transformation form. Design purpose can be obtained by properly choosing the frequency dependent weighting functions. The objective of this study is to keep the tracking error and steering input energy small in the presence of variations of the cornering stiffness coefficients. Furthermore, good ride quality has to be achieved against these uncertainties. Frequency-domain analyses and time-domain numerical simulations are carried out in order to evaluate these performance specifications of a given vehicle system. Finally, the simulation results indicate that the proposed robust controller achieves good performance over a wide range of uncertainty for the given maneuvers.

World research trends and problems in papers relating metal contamination level of herbal medicines (한약 금속오염과 관련된 세계적인 인식경향 -발표된 논문을 중심으로-)

  • Lee Sun-Dong;Lee Jung-Seok;Park Kyung-Sik
    • Journal of Society of Preventive Korean Medicine
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    • v.6 no.1
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    • pp.117-128
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    • 2002
  • Metal problems in herbal medicine are not regulate properly by law and public management around world country until this time. General people belief as safety about herbal since natural material. And almost all persons can also purchase by their-self and use by self-prescription in reality. As this result herbal medicines can always occur acute and chronic toxicity by not proper use problems, side-effect and overdose. Heavy metal toxic diseases in historical view point was big accidents that didnot forget including minamata and itai-itai in Japan. These accident's teach to us must not use toxic metal level and not include or at least Pb Hg As Cd in all kind material use and intake by people, especially herbal. Herbal contamination research is beginner state that had not many papers until nowadays. Even if this pan had some papers, it had negative result and bigger and larger than problems level because of one way research trend of not many sample case-report and screening test of dried herbal form in chiefly. Many persons have afraid and risk thinking about herbal, animal and minerals since these cause. Further research related this subject will be needed at fact of epidemiology including case-control and cohort study for more precision research affecting in short and long term intake of oriental medicines

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u-Mart Network using RFID/USN based Movement-Reader Device for Effective Shopping of Customer (고객의 효율적인 쇼핑을 위한 RFID/USN 기반 이동형리더기를 이용한 u-마트 네트워크)

  • Diao, Jianhua;Yang, Jin-Ho;Ahn, Byeong-Tae;Kang, Hyun-Syug
    • The Journal of the Korea Contents Association
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    • v.8 no.5
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    • pp.104-112
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    • 2008
  • RFID/USN is considered important basic infra of ubiquitous community and tried practical adaption through various research. Specially, there is during researcher progresses for stock and state management of logistics to let you get at u-mart systems. It discern thing from warehouse to deliver as adhere RFID tag of palette in keeping unit of article and construct form of thing to analyze information of environment status using sence module based on function of wireless communication. in the paper, propose composition of customer satisfaction system using RFID chip in u-Mart status management system based on RFID/USN and according to analysis specific information of commodity, propose movement reader device to offer real-time information from customer. And it presents the improvement program for the provision of product information which is appropriate uses the RFID chip and the provision of control information in the customer who is a core of consuming.

Integrated Hybrid Modeling Methodology and Simulation Engine Design Based on HDEVS Formalism (HDEVS 형식론에 기반한 통합 하이브리드 모델링 방법론 및 시뮬레이션 엔진 설계)

  • Kwon, Se Jung;Sung, Changho;Song, Hae-Sang;Kim, Tag Gon
    • Journal of the Korea Society for Simulation
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    • v.22 no.1
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    • pp.21-30
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    • 2013
  • A hybrid system is a combination of sub systems which have different types of state and time: a typical example is a combination of discrete event and continuous systems. A HDEVS(Hybrid DEVS) formalism was proposed for modeling and analyzing a hybrid system. The HDEVS formalism allows modelers to construct a hierarchical and modular model based on the mathematical set theory. Because the HDEVS formalism was applied to the distributed and interoperated simulators, modelers should make several heterogenous models dividing a target system. Hence, this paper proposes an extended hybrid coupled model of HDEVS formalism and an integrated hybrid modeling methodology in contrast to the existing simulation framework on interoperable simulators. By applying the proposed modeling method, a target system can be translated to a hybrid model in a similar form as the target system. This paper also contains a simulation engine design for the proposed modeling methodlogy and a case study which simulates water tank control systems.

A control dispersion of $TiO_2$ nano powder for electronic paper of electrophoresis (전기영동형 전자종이를 위한 $TiO_2$ 나노분말의 분산 제어)

  • Kim, Jung-Hee;Oh, Hyo-Jin;Lee, Nam-Hee;Hwang, Jong-Sun;Kim, Sun-Jae
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.07a
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    • pp.324-327
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    • 2005
  • An electrophoretic display using $TiO_2$ particles is the most promising candidate because it offers various advantages such as ink-on-paper appearance, good contrast ratio, wide viewing angle, image stability in the off-state and extremely low power consumption. The core technology of electrophoretic display is the dispersion controlling of $TiO_2$ nano particles in nonaqueous solution. To prepare an ink for electronic paper using electrophoretic properties of $TiO_2$ nano particles, cyclohexane with low dielectric constant and transparency, polyethylene for producing polymer coating layer which reduces apparent gravity of $TiO_2$, and $TiO_2$ powders were mixed together by planetary-mill. The zeta-potential value of $TiO_2$ particles in cyclohexane was measured about -40mV, but was measured over -110mV by dispersant attached to polyethylene-coated $TiO_2$ surface. Prepared electronic ink was filled in cross patterned micro-wall with $200{\mu}m$ in width and $40{\mu}m$ in height on ITO glass designed by photolithography. The response time of electronic paper evaluated by mobility of $TiO_2$ particle between micro-walls was measured 0.067sec, but the drift velocity from reflectance wave form during reverse from of electronic ink was measured 0.07cm/sec.

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Effects of ground motion frequency content on performance of isolated bridges with SSI

  • Neethu, B;Das, Diptesh;Garia, Siddharth
    • Earthquakes and Structures
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    • v.13 no.4
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    • pp.353-363
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    • 2017
  • The present study considers a multi-span continuous bridge, isolated by lead rubber bearing (LRB). Dynamic soilstructure interaction (SSI) is modelled with the help of a simplified, sway-rocking model for different types of soil. It is well understood from the literature that SSI influences the structural responses and the isolator performance. However, the abovementioned effect of SSI also depends on the earthquake ground motion properties. It is very important to understand how the interaction between soil and structure varies with the earthquake ground motion characteristics but, as far as the knowledge of the authors go, no study has been carried out to investigate this effect. Therefore, the objectives of the present study are to investigate the influence of earthquake ground motion characteristics on: (a) the responses of a multi span bridge (isolated and non-isolated), (b) the performance of the isolator and, most importantly, (c) the soil-structure interaction. Statistical analyses are conducted by considering 14 earthquakes which are selected in such a way that they can be categorized into three frequency content groups according to their peak ground acceleration to peak ground velocity (PGA/PGV) ratio. Lumped mass model of the bridge is developed and time history analyses are carried out by solving the governing equations of motion in the state space form. The performance of the isolator is studied by comparing the responses of the bridge with those of the corresponding uncontrolled bridge (i.e., non-isolated bridge). On studying the effect of earthquake motions, it is observed that the earthquake ground motion characteristics affect the interaction between soil and structure in such a way that the responses decrease with increase in frequency content of the earthquake for all the types of soil considered. The reverse phenomenon is observed in case of the isolator performance where the control efficiencies increase with frequency content of earthquake.