• Title/Summary/Keyword: Air Layer

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Accommodation of Trade Measures for Environment Purposes on the WTO Rules (환경조치의 WTO체제 수용에 관한 연구)

  • Chae, Dae-Seok;Kim, Mie-Jung
    • International Commerce and Information Review
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    • v.13 no.3
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    • pp.433-457
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    • 2011
  • This study attempts to make a constructive contribution to the debate on which WTO rules accommodate trade measures for environmental purposes. Does trade undermine the regulatory efforts of governments. However, the theoretical dimensions are partly addressed on the several key questions. For instances, is economic integration through trade and investment a threat to the environment? to control pollution and resource degradation? Will economic grow driven by trade help us to move towards a sustainable use of the world's environmental resources? The growing world economy has been accompanied by environmental degradation including deforestation, losses in bio-diversity, global warming, air pollution, depletion of the ozone layer, overfishing and so on. The sheer number of us obviously put pressure on natural resources and ecological systems, and this pressure will counting to rise as we grow towards 10 billion in the next century. What is more, there is no indication that consumption per capita is slowing. The perceived costs of acting alone in terms of lost investments and jobs often take the stream out of regulatory initiatives. In the worst case scenario environmental community is fearful that international trade will magnify the effects of poor environmental polices in the world Generally, economic growth drive by trade may speed up the process of environmental degradation unless sufficient environmental safeguards are put in place. Under these circumstances, this paper attempts to make a constructive contribution to the study on which WTO rules accommodate trade measures for environmental purposes.

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Temperature Characteristics of Wet-mixing Solidified Soil Pavement (습식교반경화토포장의 온도특성)

  • Yoo Ji-Hyeung;Lee Seong-Won;Kim Dae-Sung
    • International Journal of Highway Engineering
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    • v.8 no.1 s.27
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    • pp.45-54
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    • 2006
  • The Construction policy of government ever since 1970s have brought the economical growth, but has been causing environmental problems. Most roads were paved either asphalt concrete or portland cement concrete. These types of pavements has caused to rise temperature by making local heat islands in urban during summer time. Recently the wet-mixing solidified soil pavement, a kind of soil-cement, has developed and has been applied to the environment-oriented pavement. The solidified soil wet-mixed is placed on the subgrade along with asphalt concrete and portland cement concrete. Thermistors are laid in these field test pavements. The temperature gradients of these pavements are automatically measured with time. As the results of this test, the equation estimating surface temperature of pavement is proposed by analyzing measured temperature data. It is shown that the temperature change within the surface layer due to the change of air temperature is the greatest in the asphalt mixture and the least in the solidified soil mixture. Since it is proven that this wet-mixing solidified soil pavement emit less radiant heat than other existed pavements. Therefore this type of pavement can be successfully applied to the roads, such as walks, parkways, and bikeways, which are required to be human-friendly and environment-oriented.

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Structure and Evolution of a Numerically Simulated Thunderstorm Outflow (수치 모사된 뇌우 유출의 구조와 진화)

  • Kim, Yeon-Hee;Baik, Jong-Jin
    • Journal of the Korean earth science society
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    • v.28 no.7
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    • pp.857-870
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    • 2007
  • The structure and evolution of a thunderstorm outflow in two dimensions with no environmental wind are investigated using a cloud-resolving model with explicit liquid-ice phase microphysical processes (ARPS: Advanced Regional Prediction System). The turbulence structure of the outflow is explicitly resolved with a high-resolution grid size of 50m. The simulated single-cell storm and its associated Kelvin-Helmholtz (KH) billows are found to have the lift stages of development maturity, and decay. The secondary pulsation and splitting of convective cells resulted from interactions between cloud dynamics and microphysics are observed. The cooled downdrafts caused by the evaporation of rain and hail in the relatively dry lower atmosphere result in thunderstorm cold-air outflow. The outflow head propagates with almost constant speed. The KH billows formed by the KH instability cause turbulence mixing from the top of the outflow and control the structure of the outflow. Ihe KH billows are initiated at the outflow head, and pow and decay as moving rearward relative to the gust front. The numerical simulation results of the ratio of the horizontal wavelength of the fastest growing perturbation to the critical shear-layer depth and the ratio of the horizontal wavelength of the billow to its maximum amplitude are matched well with the results of other studies.

MTSAT Satellite Image Features on the Sever Storm Events in Yeongdong Region (영동지역 악기상 사례에 대한 MTSAT 위성 영상의 특징)

  • Kim, In-Hye;Kwon, Tae-Yong;Kim, Deok-Rae
    • Atmosphere
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    • v.22 no.1
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    • pp.29-45
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    • 2012
  • An unusual autumn storm developed rapidly in the western part of the East sea on the early morning of 23 October 2006. This storm produced a record-breaking heavy rain and strong wind in the northern and middle part of the Yeong-dong region; 24-h rainfall of 304 mm over Gangneung and wind speed exceeding 63.7 m $s^{-1}$ over Sokcho. In this study, MTSAT-1R (Multi-fuctional Transport Satellite) water vapor and infrared channel imagery are examined to find out some features which are dynamically associated with the development of the storm. These features may be the precursor signals of the rapidly developing storm and can be employed for very short range forecast and nowcasting of severe storm. The satellite features are summarized: 1) MTSAT-1R Water Vapor imagery exhibited that distinct dark region develops over the Yellow sea at about 12 hours before the occurrence of maximum rainfall about 1100 KST on 23 October 2006. After then, it changes gradually into dry intrusion. This dark region in the water vapor image is closely related with the positive anomaly in 500 hPa Potential Vorticity field. 2) In the Infrared imagery, low stratus (brightness temperature: $0{\sim}5^{\circ}C$) develops from near Bo-Hai bay and Shanfung peninsula and then dissipates partially on the western coast of Korean peninsula. These features are found at 10~12 hours before the maximum rainfall occurrence, which are associated with the cold and warm advection in the lower troposphere. 3) The IR imagery reveals that two convective cloud cells (brightness temperature below $-50^{\circ}C$) merge each other and after merging it grows up rapidly over the western part of East sea at about 5 hours before the maximum rainfall occurrence. These features remind that there must be the upward flow in the upper troposphere and the low-layer convergence over the same region of East sea. The time of maximum growth of the convective cloud agrees well with the time of the maximum rainfall.

Qualitative Research on Wearing Conditions and Health-Related Wearing Perception of Older Women (고령 여성의 착의 실태와 건강 관련 착의 인식에 대한 질적 연구)

  • Shim, Huen Sup;Lee, Yun Jung;Kweon, Soo Ae;Chung, Hae Won;Yoo, Shin Jung;Park, Joonhee;Park, Joo Hee;Jeong, Woon Seon
    • The Korean Journal of Community Living Science
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    • v.28 no.1
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    • pp.17-28
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    • 2017
  • The purpose of this qualitative research was to examine the behavior patterns and activities related to the clothing of older women. A total of 31 older women were interviewed regarding indoor/outdoor wearing conditions, thermal sensation indoors, and their clothing perception related to health. The final outcomes were as follows. Firstly, interviewees viewed indoor temperature as neutral in the spring and fall. Many people felt cool or warm in the summer and warm or cold in the winter. Secondly, they controlled indoor temperature with an air conditioner and/or fan and by opening the window and/or wearing less clothing. In winter, most respondents used a heating system and wore more clothing. It seemed that the level of dependence on clothing was higher in winter. Thirdly, the number of garment layer indoors was similar among the four seasons, and many wore underwear. However, there were individual variations. Fourthly, interviewees tended to perceive clothing in relation to health. Textile materials appropriate to the season were firstly viewed as related to health, followed by climate adaptability, clothing pressure, UV protection, and aesthetic satisfaction. Fifthly, respondents showed positive attitudes towards health improvement by clothing even though they lacked information on it. From this research, older women showed positive the perception and attitudes regarding clothing from a health perspective. Since they lacked information, education is needed regarding the bases and ways to improve health through clothing behavior.

The Roles of Gold Plate (140${\mu}{\textrm}{m}$) Loaded on TLD-100 Chips in the High Energy Radiation Beams (고에너지 광자선속에서 TLD-100 chip 위에 있는 금박막(140 ${\mu}{\textrm}{m}$) 역할)

  • Vahc, Young-Woo;Park, Kyung Ran.
    • Progress in Medical Physics
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    • v.6 no.2
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    • pp.51-60
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    • 1995
  • Lithium Fluoride (LiF; TLD-100) crystal chips are normally used as thermolu minescence dosimeters (abbreviated as NC-100) for estimating the absorbed dose to the skin of a patient or in a solid water phantom undergoing radiotherapy with megavoltage photon (6 and 15MV) beams. In general, investigation has revealed a reduction in the sensitivity of NC-100 chips after many runs through heating cycles. A TLD-100 chip laminated with gold plate (140${\mu}{\textrm}{m}$) on the upper surface layer of its face toward the photon beam (abbreviated as GC-100) has properties different from that of a NC-100 chip activated by incident photons and contaminant electrons with various lower energies coming from the gantry head and air. Activation of the valence band electrons of GC-100 chips by incident photons, positrons and electrons-which come from the gold plate by mainly pair production process and partly from Compton scattering-results in more enhanced signal intensity, higher response per monitor unit, as well as a good linearity with monitor units and independence of dose rate. Since the electron beams (6 and 15 MeV) do not have the probability of pair production process with gold plate, there is only a small difference (about a 3.3% increase for 15 MeV) in the signal gaps in the TL readout for electron beams between GC- and NC-100 chips. The 3.3% increase is entirely due to the buildup caused by the 140 m gold plate. The sensitivity of GC-100 chips is much more susceptible to high energy photon beams than electron one because of pair production. The interaction of high energy photon with a material of high atomic number, such as the good plate in this case, results in a considerably significant probability of pair production. The gold plate on the NC-100 chips acts as not only an intensifier of their signals but also acts as a filter of contaminant electrons in therapeutic high energy X-ray beams.

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A Study on Present State of Preservation of Excavated Remains in Chungcheongnam-do and Preservation Methods (충청남도 발굴유구 보존현황 및 보존방안 연구)

  • Wi, Koang-Chul;Oh, Seung-Jun;Jung, Je-Won
    • Journal of Conservation Science
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    • v.33 no.6
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    • pp.541-552
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    • 2017
  • All excavated "buried cultural properties" are supervised by the Cultural Heritage Administration that decides whether to conserve them or not, depending on the necessity for conservation. Currently, there is no legal regulation concerning the administration of relics (including artifacts) and remains (including archaeological sites) that are relocated and restored based on such conservation decisions. Thus, administration of these cultural properties is inadequate. Under these circumstances, this paper recommends the current state of conservation and conservation methods for buried cultural properties excavated at Chungcheongnam-do thus far. Conservation of buried cultural properties excavated at Chungcheongnam-do primarily employ the "relocating and restoration" method; 23 relics and 46 remains employed relocation after dismantling and soil layer transcription method. Moreover, 27 remains were relocated after dismantling and 14 remains employed the transcription method. In terms of area, Buyeo-gun and Gongju-si had 12 relics accounting for about 50%, while according to the period, Baekjae period had 16 relics, accounting for about 70%. In terms of conservation facility, open-air facility had 33 relics, accounting for about 72%. Results of investigating the state of relics' management indicated that public institutions like a museum with a recognizable management system had their own work force and consequently ensured excellent conservation, whereas if there were no apparent responsible bodies, remains were subjected to considerable damage due to mismanagement. Therefore, this problem can be resolved by identifying a recognizable management body as well as ensuring periodical management and supervision. The excavated buried cultural properties are utilized not only for academic purposes, but also for PR or as exhibition material. Hence, this study confirms that meticulous management of buried cultural properties is currently required.

Review of Failure Mechanisms on the Semiconductor Devices under Electromagnetic Pulses (고출력전자기파에 의한 반도체부품의 고장메커니즘 고찰)

  • Kim, Dongshin;Koo, Yong-Sung;Kim, Ju-Hee;Kang, Soyeon;Oh, Wonwook;Chan, Sung-Il
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.6
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    • pp.37-43
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    • 2017
  • This review investigates the basic principle of physical interactions and failure mechanisms introduced in the materials and inner parts of semiconducting components under electromagnetic pulses (EMPs). The transfer process of EMPs at the semiconducting component level can be explained based on three layer structures (air, dielectric, and conductor layers). The theoretically absorbed energy can be predicted by the complex reflection coefficient. The main failure mechanisms of semiconductor components are also described based on the Joule heating energy generated by the coupling between materials and the applied EMPs. Breakdown of the P-N junction, burnout of the circuit pattern in the semiconductor chip, and damage to connecting wires between the lead frame and semiconducting chips can result from dielectric heating and eddy current loss due to electric and magnetic fields. To summarize, the EMPs transferred to the semiconductor components interact with the chip material in a semiconductor, and dipolar polarization and ionic conduction happen at the same time. Destruction of the P-N junction can result from excessive reverse voltage. Further EMP research at the semiconducting component level is needed to improve the reliability and susceptibility of electric and electronic systems.

Application of coagulation pretreatment for enhancing the performance of ceramic membrane filtration (세라믹 막여과의 성능향상을 위한 응집 전처리의 적용)

  • Kang, Joon-Seok;Song, Jiyoung;Park, Seogyeong;Jeong, Ahyoung;Lee, Jeong-Jun;Seo, Inseok;Chae, Seonha;Kim, Seongsu;Kim, Han-Seung
    • Journal of Korean Society of Water and Wastewater
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    • v.31 no.6
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    • pp.501-510
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    • 2017
  • In this study, it is estimated that ceramic membrane process which can operate stably in harsh conditions replacing existing organic membrane connected with coagulation, sedimentation etc.. Jar-test was conducted by using artificial raw water containing kaolin and humic acid. It was observed that coagulant (A-PAC, 10.6%) 4mg/l is the optimal dose. As a results of evaluation of membrane single filtration process (A), coagulation-membrane filtration process (B) and coagulation-sedimentation-membrane filtration process (C), TMP variation is stable regardless of in Flux $2m^3/m^2{\cdot}day$. But in Flux $5m^3/m^2{\cdot}day$, it show change of 1-89.3 kpa by process. TMP of process (B) and (C) is increased 11.8, 0.6 kpa each. But, the (A) showed the greatest change of TMP. When evaluate (A) and (C) in Flux $10m^3/m^2{\cdot}day$, TMP of (A) stopped operation being exceeded 120 kpa in 20 minutes. On the other hand, TMP of (C) is increased only 3 kpa in 120 minutes. Through this, membrane filtration process can be operated stably by using the linkage between the pretreatment process and the ceramic membrane filtration process. Turbidity of treated water remained under 0.1 NTU regardless of flux condition and DOC and $UV_{254}$ showed a removal rate of 65-85%, 95% more each at process connected with pretreatment. Physical cleaning was carried out using water and air of 500kpa to show the recovery of pollutants formed on membrane surface by filtration. In (A) process, TMP has increased rapidly and decreased the recovery by physical cleaning as the flux rises. This means that contamination on membrane surface is irreversible fouling difficult to recover by using physical cleaning. Process (B) and (C) are observed high recovery rate of 60% more in high flux and especially recovery rate of process (B) is the highest at 95.8%. This can be judged that the coagulation flocs in the raw water formed cake layer with irreversible fouling and are favorable to physical cleaning. As a result of estimation, observe that ceramic membrane filtration connected with pretreatment improves efficiency of filtration and recovery rate of physical cleaning. And ceramic membrane which is possible to operate in the higher flux than organic membrane can be reduce the area of water purification facilities and secure a stable quantity of water by connecting the ceramic membrane with pretreatment process.

Humidity Dependence of Tribological Behavior of DLC Films (DLC 필름의 마찰마모 특성의 습도 의존성에 대한 연구)

  • Park, Se-Jun;Lee, Kwang-Ryeol;Lee, Seung-Cheol;Ko, Dae-Hong
    • Journal of the Korean Vacuum Society
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    • v.15 no.3
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    • pp.287-293
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    • 2006
  • Diamond-like carbon (DLC) film was deposited using benzene $(C_6H_6)$ by r. f-plasma assisted chemical vapor deposition. The tribological properties of the DLC film were tested by rotating ball-on-disc type tribometer isolated by a chamber. The tribological test was performed in air environment of relative humidity ranging from 0 to 90% in order to observe the tribological behavior of the DLC film with the change of humidity. We used steel ball and DLC coated steel ball to investigate the effect of the counterface material. Using steel ball, the friction coefficient of DLC film increased from 0.025 to 0.2 as the humidity increased from 0% to 90%. In case of DLC coated steel ball which didn't form the Fe-rich debris, the friction coefficient showed much lower dependence of humidity as 0.08 in relative humidity 90%. We confirmed that the high humidity dependence of the friction coefficient using steel ball resulted from the increase of debris size with humidity and the formation of Fe-rich debris by the wear of steel ball. And the friction coefficient was immediately dropped when the relative humidity changed from 90% to 0% during test using steel ball. From this result, we confirmed that the effect of the Fe-rich debris on the friction coefficient was that Fe element in debris formed the highly sensitive graphitic transfer layer to humidity.