• Title/Summary/Keyword: Critical points

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Han River Pollution Studies (한강의 오염도)

  • Choe, Sang
    • 한국해양학회지
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    • v.7 no.1
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    • pp.24-45
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    • 1972
  • The Han River is an important water source in Seoul and neighbouring districts, for public and industrial supply, and for agriculture and fishery. Nowadays, more than six million inhabitants are supplied withe water from this river. The total length of the river is 470km, and has 17 10$\^$9/㎥ an average annual flow. The hydrographic characteristics at Seoul are 653㎥/sec in an average flow, 4,608㎥/sec in the maximum average flow, and 201㎥/sec in the minimum average flow. These are influenced in some degree by snowmelt in early spring, and greatly by the flood during summer. For the pollution problems, the periods of low flow are critical ones. As a rule they occur around the months November through June. Nowadays, most of the sewage from towns and industries is discharged untreated. Apart from domestic and industrial sewages, there are some discharges of mineral matter by mines in the upriver region. In general, water quality of the Han River is kept very clean and healthy until Kwangnaru of the upper region of Seoul. A large pollution, however, is received in the downstream by the domestic and industrial sewages of Seoul. It can be seen that dissolved oxygen, COD and BOD$\sub$5/ diminish markedly, and the intensity of almost every water parameter of the river continues to increase. Comparison of the figures for 1971 derived from a sampling point 40km downstream of Kwangnaru leads to the conclusion that hardness, Ca and Mg were no changed; alkalinity, Si and soluble- Fe were slightly increased; CO$\sub$2/, acidity, Cl, NO$\sub$2/-N, Cu, Zn and Al were increased in 2 and 3 times; total residue, total ignitious residue, COD, BOD$\sub$5/, NH$\sub$4/-N, PO$\sub$4/-P, Mn, Pb and total-Fe were increased in 4 to 7 times; and SO$\sub$4/, particulate-Fe and Cd were increased in 10 to 11 times. On the other hand, coliforms were increased in 650 times; fecal coliforms in 365 times; enterococci and total plate counts in 30 times, respectively. In view points of water quality standards, the down Han River water is now leveling out in Cd, coliforms and fecal coliforms for the agricultural use; in dissolved oxygen and some trace elements (Cu, Zn, Pb and Cd) for the fishery use; in ammonia, COD, BOD$\sub$5/, and Cd for the drinking use.

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A Study on Isoelectric Point and Softness of an Ethylene Oxide Adducted Amphoteric Surfactant (에틸렌 옥사이드가 부가된 양쪽성 계면활성제의 등전점 및 유연력에 관한 연구)

  • Lim, JongChoo;Park, JunSeok;Han, DongSung;Kim, JiSung;Lee, Seul;Mo, DaHee;Lee, JinSun
    • Applied Chemistry for Engineering
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    • v.23 no.6
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    • pp.521-528
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    • 2012
  • In this study, we analyzed the physical properties of an ethylene oxide adducted amphoteric surfactant such as critical micelle concentration, surface tension, interfacial tension, contact angle, viscosity and phase behavior. The dual function characteristics of an amphoteric surfactant were investigated by determining an isoelectric point, which were attained using zeta potential measurements and quartz crystal microbalance (QCM) experiments. The isoelectric points of DE3-OSA82-AO, DE5-OSA82-AO and DE9-OSA82-AO surfactant systems determined by zeta potential measurements were 6.97, 6.93 and 7.10 respectively and they are in good agreement with the isoelectric point values measured by QCM experiments. The frictional property measured using an automated mildness tester showed that the DE-OSA82-AO surfactant could provide a good softening effect at neutral condition.

Problems in Quantification of Adequacy of Academic Library Collections -Critical Analysis of Standards for Academic Libraries in the U.S.- (종합대학 도서관장서의 적정량기준 설정에 관한 고찰 -미국의 종합대학도서관기준을 중심으로-)

  • Chung Young Sun
    • Journal of the Korean Society for Library and Information Science
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    • v.8
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    • pp.183-207
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    • 1981
  • Library standards have been the source of considerable controversy, whereas many problems are involved in developing stardard for university library collections. For evaluation purposes, standards should be precise, quantifiable and measurable. In the United States, however, standards for academic libraries are limited to qualitative statements and principles. Quantitative standards, when given, are ususally related to the number of population in the institution being served, or the prescribed quantitative objectives are often arbitrarily formulated by value judgements. The study in this paper attempts to explain the problems involved in developing quantitative standard for academic library collections. Two problems facing in the formulation of the optimal size of collection are identified. One is the theoretically faulty concept of adequacy of collection to meet the situations of diversity of university libraies, and the other is the difficulties in quantification and measurement, along with the lack of concept of adequacy of collection. However, quantification of adequate size of collection is proved to be useful on the pratical level, even though not valid theoretically. ACRL, Clapp/Jordan and Voigt developed formulas or models for setting the optimal size of a library collection for any particular university library. The main purpose of this study is the analysis of the above formulas. ACRL standard was drawn from obervation and analysis of statistcs in leading library collections. In academic field, this judgement appears to have been based on the assumption that a high-grade institution would be apt to have a good library collection. This study criticizes ACRL standard for its failure to include some determinants of measurements, and points out the limitations of the standard. In contrast. Clapp/Jordan developed a formula rather scientifically based upon bibliographical sources. This is similarly empirical but has the advantage of bringing into play the elements which make universities diverse in nature. Both ACRL and Clapp/Jordan formulas share two major defects. (1) the specific subject needs of the collection are not indiacted directly, and (2) percentage rate of growth is an indicator in measuring the potential utility of a collection. Thus both formulas failed to provide a basis for meaningful evaluation. Voigt further developed a model for determining acquisition rates for currently published materials based on bibliographic technique. Voigt model encourages experimentation with different programs and different allocations of input resources, designed to meet the needs of the library's particular population. Standard for university library collections can be formulated in terms of input(traditional indicator), or additionally, in terms of output(cost-effectiveness). Cost effectiveness is expressed as user satisfaction, ability to provide wanted materials within a reasonable time period. Thus simple quantitative method does not cover all the situations of diversity of university library collections, nor measures the effectiveness of collections. Valid standard could not be established without further research.

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Out-of-Plane Buckling Analysis of Curved Beams Considering Rotatory Inertia Using DQM (미분구적법(DQM)을 이용 회전관성을 고려한 곡선 보의 외평면 좌굴해석)

  • Kang, Ki-jun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.10
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    • pp.300-309
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    • 2016
  • Curved beams are increasingly used in buildings, vehicles, ships, and aircraft, which has resulted in considerable effort towards developing an accurate method for analyzing the dynamic behavior of such structures. The stability behavior of elastic curved beams has been the subject of many investigations. Solutions to the relevant differential equations have traditionally been obtained by the standard finite difference or finite element methods. However, these techniques require a great deal of computer time for a large number of discrete nodes with conditions of complex geometry and loading. One efficient procedure for the solution of partial differential equations is the differential quadrature method (DQM). This method has been applied to many cases to overcome the difficulties of complex algorithms and high storage requirements for complex geometry and loading conditions. Out-of-plane buckling of curved beams with rotatory inertia were analyzed using DQM under uniformly distributed radial loads. Critical loads were calculated for the member with various parameter ratios, boundary conditions, and opening angles. The results were compared with exact results from other methods for available cases. The DQM used only a limited number of grid points and shows very good agreement with the exact results (less than 0.3% error). New results according to diverse variation are also suggested, which show important roles in the buckling behavior of curved beams and can be used for comparisons with other numerical solutions or experimental test data.

Critical Re-illumination of Modern Art-a Prospect beyond the Postmodernism (현대미술의 비평적 재조명-포스트모더니즘 이후의 전망)

  • Sim, Sang-Yong
    • The Journal of Art Theory & Practice
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    • no.8
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    • pp.123-144
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    • 2009
  • The history of art during the first half of the last decade was founded the discussion with highly impressive and confident. The art might establish its unique area based on self recognition at that era. The self-confidence of modern art may be possible on enlightenment, which is the firm relationship for knowledge and reality. However the faith of modernism which shows rational tendency, objective, and the existence of universal knowledge has been drastically doubted and criticized thereafter. A internal ideological system which had leaded the modern art was exhausted. Postmodernism revolved to the dramatic openness leaning against the deoedipalizational confession. According to the dissipation of the vitality of modern art postmodern art has been evolved and then various phenomena which follow the trends has been emerged. The avant-garde and resisteive attribute of modern art was diluted fast due to the influx of popular culture. As time goes it can be attracted by spectacle taste than metaphysical peculiarity. It has to inevitably justified the drift of light and quick themes, contents, and images. Such as these phenomena realistically shows fact that postmodern art had been failed to open a new chapter of consilience which intermediates beauty and usual communication to overcome the solipsism of modernism. A trial to pursuit the opened esthetics conceived more 'heroic' 'Star-Subject' than before by dismantling the modern 'Hero-Subject'. Postmodernism has been recorded as a regression of art, which is the technology of profound spirit that mitigates antagonism and confrontation and mediates mutual encountering of human being. Prevailing of postmodern freedom had been accompanied by popularity, osetentation consumption, marketing, gambling level exitement, mixtures of desires with price fluctuations. We witness 'self-confinement' and 'lasting absence of exit' phenomena in postmodernism ideology and practice. We have to deal postmodernism as an 'ideology which closes the discussion for the future' in the context of 'absence of way' at this point. We are going to investigate how postmodern ideology and practice takes part in the prospection beyond thereafter through discussion. We also pay attention to the 'absence of prospection' as a internal problem in itself nevertheless mention the three merge points such as tradition or memory, earthy thought, the self who confrontation others as the clue of prospecting thought which is allowing coming over postmodern absence.

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"Poor Theatre, Poor Art" - Jerzy Grotowsky's Play and Arte Povera ('가난한 연극, 가난한 미술' - 그로토프스키 연극이론과 아르테 포베라)

  • Kang, Young-Joo
    • The Journal of Art Theory & Practice
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    • no.5
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    • pp.109-133
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    • 2007
  • What a concept of theatricality in modern art became more controversial is through a review "art and object-hood" on Michael Fried's minimal art, as having been already known broadly. As he had been concerned, the art following the minimalism is accepting as the very important elements such as the introduction of temporality, the stage in the exhibition space, and the audience's positive participation, enough to be no exaggeration to say that it was involved in almost all the theatricality. Particularly even in the installation art and the environment art, which have substantially positioned since the 1970s, the space is staged, and the audience's participation is greatly highlighted due to the temporal character and the site-specific in works. In such way, the theatricality in art work is today regarded as one of the most important elements. In this context, it is thought to have significance to examine theatricality, which is shown in the works of Arte Povera artists, who had been active energetically between 1967-1971. That is because the name of this group itself is what was borrowed from "Poor Theatre" in Jerzy Grotowski, who is a play director and theorist coming from Poland, and because of having many common points in the aspect of content and form. It reveals that the art called Arte Povera is sharing many critical minds in the face of commanding the field called a play and other media. Grotowski's theatre theory is very close to the theory and substance in Arte Povera in a sense that liberates a play, which was locked in literature, above all, renews the relationship between stage and seat and between actor and audience, and pursues a human being's change in consciousness through this. That is because Arte Povera also emphasizes the communication with the audience through appealing to a human being's perception and through the direct and living method, not the objective art concept of centering on the work. In addition, the poor play or poor art all has tendency that denies a system, which relies upon economic and cultural system, and seeks for what is anti-cultural, elemental, and fundamental. It is very similar even in a sense that focuses on the exploration process itself rather than the result, excludes the transcendental concept, and attaches importance to empiricism. However, Arte Povera accepts contradictoriness and complexity, and suggests eclecticism and tolerance, thereby being basically the nomadic art and the art difficult to be captured constitutively. On the other hand, there is difference in a sense that the poor play is characterized by purity, asceticism, seriousness, and solemnity. If so, which significance does this theatricality, which was introduced to art, ultimately have? As all the arts desire to be revealed with invisible things beyond the visual thing, theatricality comes to play a very important role at this time. If all the artists and audiences today came to acquire actual or virtual freedom much more, that can be said to be a point attributable to that art relied upon diverse conditions in a play.

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Behavior Pattern Modeling based Game Bot detection (행동 패턴 모델을 이용한 게임 봇 검출 방법)

  • Park, Sang-Hyun;Jung, Hye-Wuk;Yoon, Tae-Bok;Lee, Jee-Hyong
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.3
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    • pp.422-427
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    • 2010
  • Korean Game industry, especially MMORPG(Massively Multiplayer Online Game) has been rapidly expanding in these days. But As game industry is growing, lots of online game security incidents have also been increasing and getting prevailing. One of the most critical security incidents is 'Game Bots', which are programs to play MMORPG instead of human players. If player let the game bots play for them, they can get a lot of benefic game elements (experience points, items, etc.) without any effort, and it is considered unfair to other players. Plenty of game companies try to prevent bots, but it does not work well. In this paper, we propose a behavior pattern model for detecting bots. We analyzed behaviors of human players as well as bots and identified six game features to build the model to differentiate game bots from human players. Based on these features, we made a Naive Bayesian classifier to reasoning the game bot or not. To evaluated our method, we used 10 game bot data and 6 human Player data. As a result, we classify Game bot and human player with 88% accuracy.

Efficiency Analysis for RFID-based Curtain Wall of unit Type Construction (RFID 기술 적용에 따른 유닛타입 커튼월 공사의 효율성 분석)

  • Kang, Hyun-Koo;Ha, Young-Seo;Lim, Chul-Woo;Kim, Chang-Duk;Yu, Jung-Ho
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.3
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    • pp.206-213
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    • 2008
  • Due to the following reasons, the management of curtain wall parts and material is very Important. Firstly, curtain wall work is one of the main works in High-rise building construction for it takes about $10{\sim}15%$ of the total construction cost. Secondly, the whole process of curtain wall work including manu acture, delivery, storage, installation and maintenance is very complicated and sometimes more than 30 companies involve in the process. Thus there are many control points for curtain wall units. Thirdly, there are not enough space on site for material storage and this situation is more serious for sites in urban area. The purpose of this research is to validate an information systems using RFID technology that is developed to manage the curtain wall units following the process of curtain wall work. For the validation, the cycle times of curtain wall work before and a ter the system was used. The results show that using the systems shorten the cycle time of the curtain wall work. Thus it is concluded that the system can increase the efficiency of managing curtain wall work.

The Poetics of Integration; Shi Zhen Wang's poetics and theory on Ci (통합(統合)의 시학(詩學), 왕사정(王士禎)의 시론(詩論)과 사론(詞論))

  • Kim, KouSun
    • (The)Study of the Eastern Classic
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    • no.35
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    • pp.101-133
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    • 2009
  • Shi Zhen Wang has established his own comprehensive poetics; diachronically, he integrated the main theories on poetry from Wei and Jin to Ming and synchronically the major themes and concerns including 'pure and far-off', 'strong and firm', 'Adoration of Tang', 'Adoration of Song', 'gentle and mild', 'manly and broad minded', 'Nothern Song Ci' and 'Southern Song Ci', etc. The constant goal he sought in this integration process was to represent the intrinsic value of the literary on the basis of the absolute and objective standard without leaning toward a certain value. The standards and values, which are originated from the theory of Shenyun, are founded, more exactly, on 'to reach to it with no written word', 'the meaning outside of the meaning', 'intuitional feeling', 'the nature', 'elegance and righteousness', etc. Because of this, he was able to find good points from each work without prejudice and have full use of his critical talents with objective attitude.

Human Goal in Advaita Vedānta (아드와이따 베단따와 인간의 목표)

  • Park, Hyo-yeop
    • Journal of Korean Philosophical Society
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    • v.130
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    • pp.109-134
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    • 2014
  • In (Advaita) $Ved{\bar{a}}nta$ although human beings are destined to have a pessimistic starting point in life, their goal of life is to become a Perfect Being which is called 'Liberation' (mokṣa) by self-transcendence. This human goal together with several means are accepted by $Ved{\bar{a}}nta$ as solely valuable thing in the life. In this way there must be a self-recognition of his own value in the process of Liberation, through which one recognizes his own true nature i.e. ${\bar{A}}tman$. ${\bar{A}}tman$ is clearly defined to be 'Existence, Consciousness, Bliss' (Being, Illumination, Good), and this definition is made with the view of revealing that It is ultimate foundation and source of human beings ontologically, epistemologically and axiologically. However, as $Ved{\bar{a}}ntic$points of view on human goal are not without critical limitations, it may be necessary to revaluate 'the process of self-inquiry' devised to achieve human goal. Inquiry is, first of all, an accepting process of what is given in $Ved{\bar{a}}nta$ as the scenario that gives rise to most actual result, then, a performing and verifying process of that scenario in one's own experience consistently. In this process, a shift of action from worldly life to unworldly life is what is called 'self-adjustment', a removal of 'the self in excess' through knowledge of the real Self is what is called 'simplification of the self', and at the end of simplification a state of ultimate Self is 'Liberation'. Therefore, the inquiry of $Ved{\bar{a}}nta$ into human goal can be summarized as following formula; 'good action = self-adjustment' ${\rightarrow}$ 'good knowledge = simplification of the self' ${\rightarrow}$ 'Liberation = ultimate Self'.