• Title/Summary/Keyword: The Fact of Matter

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Fundamental Studies on the Characteristics of the Surface Electrokinetic Behavior of Particulate Matter as an Extensive Property (입자성 물질의 크기성질로서의 표면 전기적 특성 규명에 대한 기초연구)

  • O, Se-Jin;Kim, Dong-Su
    • Journal of Korean Society of Environmental Engineers
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    • v.32 no.6
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    • pp.581-586
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    • 2010
  • Generally, electrokinetic potential has been considered as an intensive property. In other words, electrokinetic potential is not affected by the amount of particulate matter. Montmorillonite, one of essential inorganic matter, was chosen to measure electrokinetic potential. The result of electrokinetic potential measuring experiment showed that the value observed to decrease as the amount of montmorillonite clay increased. This is due to the fact that total ions that adsorbed per unit mass were decreased as the amount of montmorillonite was increased. As a result, electrokinetic potential is considered as an extensive property. By using these results, total interaction energy of suspension was also checked, and revealed that total interaction energy was decreased as the amount of montmorillonite increased.

Distinguishing the Effects of Environmental Stress and Forest Succession on Changes in the Forest Floor

  • Arthur, Mary A.;Ruth D. Yanai
    • The Korean Journal of Ecology
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    • v.23 no.2
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    • pp.83-88
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    • 2000
  • When interpreting change over time in forest ecosystems, distinguishing the effects of forest succession from the effects of environmental stress can be difficult. The result may be a simplistic interpretation. citing a specific successional or environmental cause of forest change when both types may be occurring. We present two case studies of changes in the forest floor in northern hardwoods. First, the belief that 50% of soil organic matter is lost in the first 20 years after logging was based on a study comparing northern hardwood stands of different ages. We resampled a series of 13 such stands after an interval of 15 years, and found that the young stands were not, in fact. losing organic matter as rapidly as predicted from the original chronosequence study. The pattern of higher organic matter content in the forest floors of older stands compared to young stands could be equally well explained by changes in logging practices over the last century as by the aging of the stand. The observed pattern of forest floor organic matter as a function of stand age was previously interpreted as a successional pattern, ignoring changes in treatment history. In the second case study, observed losses of base cations from the forest floor were attributed to cation depletion caused by acid rain and declining calcium deposition. We found that young stands were gaining base cations in the forest floor; losses of base cations were restricted to older stands. Differences in litter chemistry in stands of different ages may explain some of the pattern in cation gains and losses. In this case, the contribution of successional processes to cation loss had been overlooked in favor of environmental stress as the dominant mechanism behind the observed changes. Studies of environmental stress use repeated measures over time. but often don't consider stand age as a factor. Studies of successional change often assume that environmental factors remain constant. We were able to consider both forest succession and external factors because we repeatedly sampled stands of different ages.

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Herbicidal Phytotoxicity of Early Rice Seedlings as Affected by Cultural Practices IV. Response of Phytotoxicity with Application Rate of Fertilizer and Organic Matter (재배조건(栽培條件)의 차이(差異)가 수도(水稻)어린묘(苗의) 제초제(除草劑) 약해발생(藥害發生)에 미치는 영향(影響) IV. 시비량(施肥量) 및 유기물(有機物) 시용량(施用量)에 따른 약해반응(藥害反應))

  • Han, S.U.;Guh, J.O.;Kwon, S.L.
    • Korean Journal of Weed Science
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    • v.11 no.2
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    • pp.106-110
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    • 1991
  • There was a tendency that the growth inhibition of early growth due to herbicides was increased with increasing the amount of fertilizers. As a matter of fact, pretilachlor and pyrazolate increased the degree of injury with increasing the amount of fertilizers, and dimepiperate was actually safe regardless of the amount of fertilizer applied, while in case of bensulfuron, the injury become less when it was applied without fertilizers. As for organic matters, dimepiperate and pyrazolate were rather safe without organic matter, while pretilachlor and bensulfuron become really safe with the application of organic matter more than 1,000 kg/10a.

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Development of ICT as an evolutionary process

  • Hwang, Gyu-hee
    • Journal of Korea Technology Innovation Society
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    • v.5 no.2
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    • pp.189-211
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    • 2002
  • The research shows how the technological change of 'Information and Communication Technology' (ICT) is accompanied with the usage change. It aims to provide a better conceptualization with empirical findings about the fact that the technological development of ICT is a convergence process of ICT factors with the usage of ICT moving from a limited coverage toward a general-purpose. The research adapts a descriptive methodology on a historical matter and demonstrates how it can be conducted through analytical description of Input-Output tables (I/O) the over periods. The case is about the UK with sequential I/O during 1970s- 90s.

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Matter dynamics with respect to influences of C3 and C4 plants in four subtropical grasslands of Nilgiri Biosphere Reserve, the Western Ghats, India

  • Paulsamy, Subramanium;Kil, Bong-Soup;Sivashanmugam, Munusamy
    • Journal of Ecology and Environment
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    • v.35 no.4
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    • pp.259-267
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    • 2012
  • Biomass changes, net primary production and transfer dynamics of dry matter in four subtropical humid montane grasslands at Ebbenadu, Korakundah, Thiashola and Wenlockdown in Nilgiri Biosphere Reserve (NBR), the Western Ghats, India, were investigated. Despite the early report of a higher density and dominance of $C_4$ species over $C_3$ species in these grasslands, no functional study of matter production had previously been carried out. Therefore, in order to determine the roles played by these two groups of species, the present study was attempted. The study revealed that the dry matter and net primary production contributed by $C_4$ species were much greater than those of its $C_3$ counterpart in all the grasslands. The turnover rate of aboveground dry matter for both $C_3$ and $C_4$ species was generally rapid, whereas it was slow for belowground parts, and litter components of $C_3$ and $C_4$ species together. In all grasslands, generally about 60% and 10% of the input were channeled to aboveground and belowground parts, respectively, by the $C_4$ species, whereas the $C_3$ species transferred only about 22% and 8% of dry matter to aboveground and belowground parts, respectively. The total disappearance of dry matter was 2.73, 2.10, 3.19, and $1.96\;g\;m^{-2}\;day^{-1}$ in Ebbenadu, Korakundah, Thiashola and Wenlockdown grasslands, which was 48.83%, 44.30%, 54.81%, and 41.09% of the total input, respectively, in these grasslands. This resulted in a considerable surplus dry matter production in all the grasslands studied. This balance sheet of dry matter in community function indicates that all the four studied grasslands were supporting the existing wild animals adequately in terms of pasture supply. The study further revealed that the stronger establishment of $C_4$ species rather than their $C_3$ counterparts, in terms of higher density and dominance, has driven them to play major roles in matter dynamics and system transfer functions in all the four grasslands studied. This fact evidenced that pasture from $C_4$ species for wild animals was determined to be higher in comparison to that of $C_3$ species.

A Study on the Ecological Pavement using Road Compound (Road Compound 공법을 적용한 환경친화형 포장에 관한 연구)

  • 하상우;최연왕;신화철
    • Proceedings of the Korea Concrete Institute Conference
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    • 2003.05a
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    • pp.59-64
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    • 2003
  • As the economy of a country develops, the necessity for social overhead capital such as railroad, highway and other transportation infrastructures becomes an utmost issue as the volume of traffic increases. As the standard of living has been raised the needs for ecological road pavement also increase. As a matter of fact, the concrete and asphalt pavement have been constructed without considering the harmony with nature. The Road Compound pavement is constructed with local soils from optimum mixture proportions that did not contaminate the surroundings and represent the ecological pavement.

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A morphological study on the origin of Folium (엽류한약재(葉類韓藥材)의 기원(起源)에 관(關)한 형태학적(形態學的) 고찰(考察))

  • Ju, Yung-Sung
    • The Journal of Korean Medicine
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    • v.19 no.2
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    • pp.411-419
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    • 1998
  • For the purpose of external and internal morphological study on the origin of Folium, writing on herbolagy have been thoroughly reviewed. The object herb medicine(9 kinds) is Lophatheri Folium(Herba), Isatidis Folium, Eoriobotryae Folium, Mori Folium, Perillae Folium, Artemisiae argi Folium, Phyllostachys Folium, Clerodendri Folium, Biotae Folium(Cacumen). After this study, additional experimental verification is required as a matter of fact. As comparison materials, this thesis will be utilized.

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Fuzzy Controller : Design, Evaluation, Parallel and Hierarchical Combination with a PID Controller

  • Ketata, R.;De Geest, D.;Titli, A.
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 1993.06a
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    • pp.814-816
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    • 1993
  • Fuzzy controllers still remain ill-accepted in the control community. As a matter of fact, their design relies on a new relation between the material world and the scientists. Whereas some theoritical studies are carried out on this subject, experimentations on processes show what fuzzy techniques can bring to the control theory.

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Origin of Dark-Energy and Accelerating Universe

  • Keum, Yong-Yeon
    • Bulletin of the Korean Space Science Society
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    • 2009.10a
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    • pp.34.1-34.1
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    • 2009
  • After SNIa and WMAP observations during the last decade, the discovery of the accelerated expansion of the universe is a major challenge to particle physics and cosmology. There are currently three candidates for the dark energy which results in this accelerated expansion: $\cdot$ a non-zero cosmological constant, $\cdot$ a dynamical cosmological constant (quintessence scalar field), $\cdot$ modifications of Einstein's theory of gravity. The scalar field model like quintessence is a simple model with time-dependent w, which is generally larger than -w1. Because the different w lead to a different expansion history of the universe, the geometrical measurements of cosmic expansion through observations of SNIa, CMB and baryon acoustic oscillations (BAO) can give us tight constraints on w. One of the interesting ways to study the scalar field dark-energy models is to investigate the coupling between the dark energy and the other matter fields. In fact, a number of models which realize the interaction between dark energy and dark matter, or even visible matter, have been proposed so far. Observations of the effects of these interactions will offer an unique opportunity to detect a cosmological scalar field. In this talk, after briefly reviewing the main idea of the three possible candidates for dark energy and their cosmological phenomena, we discuss the interactinng dark-energy model, paying particular attention to the interacting mechanism between dark energy with a hot dark matter (neutrinos). In this so-called mass-varying neutrino (MVN) model, we calculate explicitly the cosmic microwave background (CMB) radiation and large-scale structure (LSS) within cosmological perturbation theory. The evolution of the mass of neutrinos is determined by the quintessence scalar field, which is responsible for the cosmic acceleration today.

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Recognition of Reasonable Causation in Cases of Mentally Ill Patients Committing Suicide and the Adequate Level of Damages (투신 사고와 자살 사이의 상당인과관계 인정과 손해배상의 범위에 대한 소고 - 대법원 2007.1.11. 선고 2005다44015 판결을 중심으로 -)

  • Lee, Jung-Sun
    • The Korean Society of Law and Medicine
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    • v.9 no.1
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    • pp.165-196
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    • 2008
  • Recently the Supreme Court held that "in cases in which a patient suffering from a mental disorder attempts to commit suicide, fails, and then succeeds in a subsequent attempt, the following circumstances must be present in order to acknowledge reasonable causation between the negligence of the hospital with regards to taking care of the patient and the death of the patient; there must have existed negligence on the part of the hospital with regards to their failure to stop the 1stsuicide attempt, injurious aftereffects must have been caused to the patient by the1stsuicide attempt, and said aftereffects must have been the main cause for the 2nd successful suicide attemtp." This, in effect, lessens the requirements of past holdings of the Supreme Court which held that "to acknowledge reasonable causation between the negligence of the hospital and the patient that commits suicide, the patient must have experienced such severe physical and mental suffering from the previous attempt so that they could not help but choose to commit suicide". The fact that the Supreme Court did not clearly state such changes in their view on this matter should be corrected. Also, the fact that the court only held the hospital liable for damages of less than 50 million won, only calculating damages up to the point when the deceased passed, is inadequate compared to other cases and should be corrected.

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