• Title/Summary/Keyword: run theory

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Mechanism of aging and prevention (노화의 기전과 예방)

  • Kim, Jay Sik
    • IMMUNE NETWORK
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    • v.1 no.2
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    • pp.104-108
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    • 2001
  • Aging is a senescence and defined as a normal physiologic and structural alterations in almost all organ systems with age. As Leonard Hayflick, one of the first gerontologists to propose a theory of biologic aging, indicated that a theory of aging or longevity satisfies the changes of above conditions to be universal, progressive, intrinsic and deleterious. Although a number of theories have been proposed, it is now clear that cell aging (cell senescence) is multifactorial. No single mechanism can account for the many varied manifestations of biological aging. Many theories have been proposed in attempt to understand and explain the process of aging. Aging is effected in individual by genetic factors, diet, social conditions, and the occurrence of age-related diseases as diabetes, hypertension, and arthritis. It involves an endogenous molecular program of cellular senescence as well as continuous exposure throughout life to adverse exogenous influences, leading to progressive infringement on the cell's survivability so called wear and tear. So we could say the basic mechanism of aging depends on the irreversible and universal processes at cellular and molecular level. The immediate cause of these changes is probably an interference in the function of cell's macromolecules-DNA, RNA, and cell proteins-and in the flow of information between these macromolecules. The crucial questions, unanswered at present, concerns what causes these changes in truth. Common theories of aging are able to classify as followings for the easy comprehension. 1. Biological, 1) molecular theories - a. error theory, b. programmed aging theory, c. somatic mutation theory, d. transcription theory, e. run-out-of program theory, 2) cellular theories - a. wear and tear theory, b. cross-link theory, c. clinker theory, d. free radical theory, e. waste product theory, 3) system level theory-a. immunologic/autoimmune theory, 4) others - a. telomere theory, b. rate of living theory, c. stress theory, etc. Prevention of aging is theoretically depending on the cause or theory of aging. However no single theory is available and no definite method of delaying the aging process is possible by this moment. The most popular action is anti-oxidant therapy using vitamin E and C, melatonin and DHEA, etc. Another proposal for the reverse of life-span is TCP-17 and IL-16 administration from the mouse bone marrow B cell line study for the immunoglobulin VDJ rearrangement with RAG-1 and RAG-2. Recently conclusional suggestion for the extending of maximum life-span thought to be the calory restriction.

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Diffraction and Radiation of Waves by Array of Multiple Buoys (다수 부체 배열에 의한 파의 회절과 방사)

  • Cho, Il-Hyoung
    • Journal of Ocean Engineering and Technology
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    • v.30 no.3
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    • pp.151-160
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    • 2016
  • The diffraction and radiation of linear waves by an array of truncated floating multiple buoys are solved using the interaction theory based on a matched eigenfunction expansion method (MEEM). The interaction processes between multiple buoys are very complex and numerous, because the scattered and radiated waves from each buoy affect the others in the array. Our primary aim is therefore to construct the rigorous wave exciting forces and hydrodynamic forces to deal with the problem of multiple interactions. This present method is applied to a square array of four buoys with two incidence angles, and the results are given for the wave excitation forces on each buoy, heave RAO for each buoy heaving independently, and wave elevations around the buoys and wave run-up. The analytical solutions are in good agreement with the numerical solutions obtained from commercial code (WAMIT).

Development of an Active Suspension System for Passenger Cars( II ) ; Prototype Car Test Result (승용차용 능동제어식 현가시스템의 개발(2); 실차 성능실험 및 결과)

  • Hwang, Y.;Hong, Y.S.;Lee, J.M.;Bae, J.Y.
    • Transactions of the Korean Society of Automotive Engineers
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    • v.2 no.2
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    • pp.83-94
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    • 1994
  • Performance test result on prototype car equipped with low-band type active suspension system is reported. Control theory is explained first. Simulation for feasibility and parameter tuning, control module test using hydraulic exciter and test run, and performance evaluation of the test car on test track are reported successively. Emphasis was put on modification of control theory which caused many unexpected problems in actual implementation.

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Development of Rigidity and Frequency Analysis Program for Corrugated Plates (주름판의 강성 및 진동수 해석 프로그램 개발)

  • Kim, Young-Wann;Chung, Kang;Park, Kyung-Jo
    • Journal of Power System Engineering
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    • v.6 no.2
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    • pp.24-32
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    • 2002
  • A program is developed to analyze and design the frequency and rigidity of the corrugated plates with various corrugation shapes (the considered corrugation shapes are triangular and trapezoidal) and 36 kinds of boundary conditions using smeared theory. The system is consisted of input, solution and output routines, and its routine is made up pull-down menu type and run in Window basis using Visual Basic Language. The input routine helps the design engineers to make the input data user-friendly. The solution routine uses the homemade solver. In the output routine, automatic designs can be done using AutoCAD and Intent Tool package by interfacing the input data.

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Climate Change Impacts on Agricultural Drought for Major Upland Crops using Soil Moisture Model -Focused on the Jeollanam-do- (토양수분모형을 이용한 주요 밭작물의 미래 가뭄 전망 -전라남도 지역을 중심으로-)

  • Hong, Eun-Mi;Nam, Won-Ho;Choi, Jin-Yong
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.3
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    • pp.65-76
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    • 2015
  • Estimating water requirements for upland crops are characterized by standing soil moisture condition during the entire crop growth period. However, scarce rainfall and intermittent dry spells often cause soil moisture depletion resulting in unsaturated condition in the fields. Changes in rainfall patterns due to climate change have significant influence on the increasing the occurrence of extreme soil moisture depletion. Therefore, it is necessary to evaluate agricultural drought for upland crop water planning and management in the context of climate change. The objective of this study is to predict the impacts of climate change on agricultural drought for upland crops and changes in the temporal trends of drought characteristics. First, the changes in crop evapotranspiration and soil moisture in the six upland crops, such as Soybeans, Maize, Potatoes, Red Peppers, Chinese Cabbage (spring and fall) were analyzed by applying the soil moisture model from commonly available crop and soil characteristics and climate data, and were analyzed for the past 30 years (1981-2010), and Representative Concentration Pathways (RCP) climate change scenarios (2011-2100). Second, the changes on the temporal trends of drought characteristics were performed using run theory, which was used to compare drought duration, severity, and magnitude to allow for quantitative evaluations under past and future climate conditions.

Projection of Temporal Trends on Drought Characteristics using the Standardized Precipitation Evapotranspiration Index (SPEI) in South Korea (표준강수증발산지수를 활용한 미래 가뭄특성의 시계열 변화전망)

  • Nam, Won-Ho;Hayes, Michael J.;Wilhite, Donald A.;Svoboda, Mark D.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.57 no.1
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    • pp.37-45
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    • 2015
  • Recent droughts in South Korea have had large economic and environmental impacts across the country. Changes in rainfall and hydrologic patterns due to climate change can potentially increase the occurrence of extreme droughts and affect the future availability of water resources. Therefore, it is necessary to evaluate drought vulnerability for water resources planning and management, and identify the appropriate mitigation actions to conduct a drought risk analysis in the context of climate change. The objective of this study is changes in the temporal trends of drought characteristics in South Korea to examine drought impacts under climate change. First, the changes of drought occurrence were analyzed by applying the Standardized Precipitation Evapotranspiration Index (SPEI) for meteorological data on 54 meteorological stations, and were analyzed for the past 30 years (1981-2010), and Representative Concentration Pathways (RCP) climate change scenarios (2011-2100). Second, the changes on the temporal trends of drought characteristics were performed using run theory, which was used to compare drought duration, severity, and magnitude to allow for quantitative evaluations under past and future climate conditions. These results show the high influence of climate change on drought phenomenon, and will contribute to water resources management and drought countermeasures to climate change.

Toward an Integrated Theory of Language (대통합 언어이론을 향하여)

  • 문경환
    • Lingua Humanitatis
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    • v.1 no.1
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    • pp.33-63
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    • 2001
  • This article does not deal with a theory or theories in the usual sense of the term but rather harks back to its etymological source, theorein ' to look at.' The phrase 'theory of language' thus purports a 'view of language' and does not carry the force of scientific explication of language. In fact, the word ' scientific' or 'science' per se originates from scire 'to know' and is here to be considered not so much in regard to some kind of positivistic methodology as a form of knowledge. If this exposition sounds unduly ingenious, that is because one is caught up in all kinds of presuppositions about the words under consideration. Sometimes, when we come to grips with an issue that strikes our mind as truly important, our language, by the light of which we hope to proceed safely, plays the will-o'-the-wisp instead and leaves us in the middle of a murky maze, twisting what was at first blush a mere cinch into a Gordian knot. On such occasions, etymology comes along the way and sends us back to itself as its own principle: Resort to etymos logos 'original, true word'! The main thrust of the present study is that alongside the quantitative, positivistic thought there is another equally valuable mode of qualitative and humanistic thinking that makes a whole gamut of new and concrete investigations possible, that an integrated theory of language is Possible by way of a happy amalgamation of diversified, humanistic views of language. With this idea as the leitmotif we explore two models of theory which typically set themselves up for a 'scientific' approach to language: analytic philosophy that delves into what it calls logical simples, and contemporary linguistics that stubbornly teeters around some formal rigor or other. It is argued that they are both characterized by a looking away from the fluid, ill-definable aspects of language, giving a preference to segments and isolated facts as a means to avoid those larger wholes and totalities which if they had to be seen would in the long run lead to an uncomfortable state of mind. Language, in the final analysis, is a Protean entity: so capricious and multifarious, and yet so noetic and prophetic, that we should catch sight of its picturesque images in their entirety to give form to an integrated theory of language.

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Hydrological Drought Analysis using Copula Theory (Copula 이론을 이용한 수문학적 가뭄 분석)

  • Kwak, Jae Won;Kim, Duck Gil;Lee, Jong Soo;Kim, Hung Soo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.32 no.3B
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    • pp.161-168
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    • 2012
  • Drought is a normal and recurrent phenomenon. But, recurring prolonged droughts have caused consequences and diverse impacts on human system. Therefore, understanding drought characteristics is indispensable element in well-prepared drought management. This study aims to investigate the hydrological droughts of Pyongchang stream and Upstream of Namhan-river in Korean peninsula. For modelling of the joint distribution of drought duration and drought severity, the copula method is used to construct the bivariate drought distribution and return period from the predetermined marginal distributions of drought duration and drought severity. As the result, the most severed drought of the Pyongchang stream and Upstream of Namhan-river occuring during period 1967 to 2007 is the 1981 and 1973. Return period for this drought derived from copula is 550 and 110 years.

A Study on the Farming Decision-making Process of Onion and Garlic Farmers by the Perspective of Behavioral Economics (양파와 마늘 농가의 행동경제학적 영농 의사결정 과정에 관한 연구)

  • Lee, Su-Mi;Kim, Ho
    • Korean Journal of Organic Agriculture
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    • v.32 no.1
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    • pp.25-37
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    • 2024
  • This study is to apply behavioral economics-an economics that studies actual human behavior based on cognitive psychology-to the farming decision-making process of onion and garlic farmers. Of behavioral economic theories, dual system theory and prospect theory (value function), heuristic and bias were surveyed and examined in the field. The reference point of farmers was farming experience of the previous year, and so they showed reference dependence and anchoring heuristic, not rational thinking on production cost plan. And they showed status quo bias that cultivated continuously the previous year or the present crop. This status quo bias is related to loss aversion propensity. Farmers did not usually change cultivating crops, in other words, they showed diminishing sensitivity-insensitive to those that the more revenue or loss was increased. This diminishing sensitivity is related to loss aversion propensity and status quo bias. Also, farmers had representativeness heuristic because they regarded auction price of Garakdong wholesale market as the standard price level despite various prices by production region. And farmers had the affect heuristic that they depended on producers' organization data more than the state-run research institute ones about cultivation intentions and actual situations.

Study of Relationship between the Chapter of Channels in Miraculous Pivot of Emperor′s Classic of Internal Medicine and Yangmyung disease in Sanghanron (『영추ㆍ경맥편』과 『상한론』의 양명병에 대한 상관성 연구)

  • Lee Seung Yeul;Shin Heung Mook
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.16 no.6
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    • pp.1085-1091
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    • 2002
  • Chang Chung-ching(張仲景) in the Later Han(Eastern Han) Dynasty of Chinese history wrote the treatise on Diseases Caused by Cold Factors(傷寒論; Shang Han Lun) on the basis of the fundamental theory of Emperor's Classic of Internal Medicine(黃帝內經; ECIM) after collecting medical treatment experiences until the Han Dynasty. It had great significance that Shang Han Lun was the origin of treating six-channels(六經) and there showed the peculiar guidelines on the diagnosis and treatment of oriental medicine to divide diseases into six-channels. The oriental medical doctors who had studied Shang Han Run thought highly of meridians and until now it was generally known that the chapter of heat in the Plain Questions of ECIM(黃帝內經, 素問ㆍ熱論) was the basis of Shang Han Run. The chapter of heat in the Plain Questions of ECIM was the first text in which the basic theory on six-channels according to the types of illness was introduced. In my point of view, the theory of treating six-channels had close relation to the Chapter of Channels in Miraculous Pivot of ECIM(黃帝內經, 靈樞ㆍ經脈篇) as well as the chapter of heat in the Plain Questions of ECIM. Therefore I took a look at the origin of treating six-channels in Shang Han Lun and illuminated again the meaning to compare the parts of in Shang Han Lun with the Chapter of Channels in Miraculous Pivot of ECIM. Conclusion: The, symptoms divided into six-channels in the chapter of channels in ECIM gave the fundamental basis of diagnosis and treatment basesd on overall analysis of signs and symptoms(辨證論治) an illness in the Zangfu(臟腑) in respect of meridians. Viewed in the light of diagnosis and treatment basesd on overall analysis of signs and symptoms(辨證論治), the symptoms of YangMing-channel(陽明經) in the Chapter of Channels in Miraculous Pivot of ECIM were, for the most part, accord with those of YangMing-disease in Shang Han Lun. Furthermore, the symptoms in Shang Han Lun were explained definitely and in detail. Therefore the theory of Shang Han Lun has been developed on the basis of ECIM with the changes of the times. YangMing-disease in Shang Han Lun implied medical cases in stomach meridian(胃經) and large intestine meridian(大腸經). Therefore Shang Han Lun was the foundation of treatment basesd on overall analysis of signs and symptoms(辨證論治) in respect of meridian as well as the text in which the steps of infectious diseases(外感病) of human bodies were explained.