• Title/Summary/Keyword: 형태지

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Effect of Dietary Supplementation of Vitamin A and Chronic Consumption of Ethanol on Oxidative Damage and Antioxidant System in Rats (비타민 A 보충 식이 및 에탄올의 만성적 급여가 흰쥐의 체내 산화적 손상과 항산화체계에 미치는 영향)

  • 양경미
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.2
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    • pp.278-286
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    • 2003
  • Alcohol is well known agent which can damage the human tissues such as liver via stimulating lipid peroxidation. On the other hand, carotenoids in addition to vitamins A, C and I play important roles in protecting these oxidative damages as well as preventing the production of free radicals. This study was carried out to investigate the effect of dietary vitamin A on lipid peroxidation and antioxidants status in ethanol-treated rats. In the experiment, male Sprague-Dawley rats weighing 160~180 g were given a liquid diet containing 36% of total calories as ethanol for 7 weeks. The pair-fed control rats received an isocaloric amount of diet containing sucrose instead of ethanol on the following day Additionally, the liquid diet contained adequate amount of $\beta$-carotene, retinyl acetate or 13-sis-reinoic acid except vitamin A-deficient diet. The results obtained are as follows. The levels of plasma and hepatic lipid peroxide were increased after chronic ethanol feeding in rats. Retinyl acetate supplementation significantly reduced lipid peroxidation induced by ethanol feeding Glucose 6-phosphatase activity was significantly reduced in rats fed vitamin A-deficient diet with ethanol and alkaline phosphatase activity was significantly induced in rats fed 13-cis-reinoic acid diet with ethanol. Catalase and alcohol dehydrogenase activities did not show a consistent tendency in experiment groups. The hepatic antioxidant enzyme activities did not significantly changed by chronic ethanol feeding groups. The striking decrease in conversion of $\beta$-carotene to retinol was observed in rats fed a $\beta$-carotene diet with ethanol feeding The level of retinol and retinoic acid in plasma and liver was decreased after chronic ethanol administration Based on this result, these data suggest that ethanol feeding enhances oxidative stress especially in those fed a vitamin A-deficient diet, and vitamin A supplementation, especially, retinyl acetate intake can prevent enhanced lipid peroxidation and related damage to some extent.

Preliminary Study on Actuated Signal Control at Rural Area of Cheon-an City (천안시 외곽지역의 감응식 신호운영을 위한 기초연구)

  • Park, Soon-Yong;Kim, Dong-Nyong
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.8 no.3
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    • pp.52-63
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    • 2009
  • Recently in Korea, in the case of metropolis, the urban signalized intersections are controlled by traffic information center or ITS center. Cheon-an City also established traffic information center through the 1st.-$\sim$3rd. ITS public construction and has managed this center that includes bus information service, traffic information collection and providing service, parking information service, and traffic responsive control system. In the Cheon-an metropolitan traffic signal operation, traffic signal controllers were grouped by the each main traffic flow axes and performed with coordinated signal timing for the signalized arterials, and also cycle and split changed by realtime traffic demands. Cheon-an urban traffic responsive control system was evaluated by intersection delay and speed, then it was verified that the delay decreased and vehicle speed improved. However, the rural signal control system to connect adjacency town was evaluated to have lower status than urban area due to the unimproved TOD (Time of day) plan. Therefore actuated signal control was examined for substitutive control system in isolated signal intersection. The aim of this article is to compare actuated signal control with TOD mode in the rural intersection of Cheon-an and to fine superiority of these two control mode, with evaluation of vehicle delay by using HCM(2000) method and by micro-simulation CORSlM. The result of field test show that actuated signal control gave better performance in delay comparison than the existing TOD signal control. And simulation outcome verified that non-optimized TOD has higher delay than optimized TOD mode, non-optimal actuated mode, and optimal actuated signal control mode. Particularly, these three modes delays had not different values according to the paired sample t-test. This is because small traffic demands were loaded in each links. This suggested actuated signal control is expected to be more effective than TOD mode in some rural isolated intersections which frequently need to survey for traffic volume.

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Electrochemical Characteristics of Transition Metal Pyrophosphate as Negative Electrode Materials through Solid-state Reaction (고상법으로 합성된 리튬이온 이차전지용 음극물질로서 전이금속 피로인산화물의 전기화학적 특성)

  • Hong, Min Young;An, Sang-Jo;Ryu, Ji Heon
    • Journal of the Korean Electrochemical Society
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    • v.23 no.4
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    • pp.105-112
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    • 2020
  • Transition metal oxide, which undergoes a conversion reaction in the negative electrode material for a lithium-ion batteries, has a high specific capacity, but still has several critical problems. In this study, manganese pyrophosphate (Mn2P2O7), nickel pyrophosphate (Ni2P2O7), and carbon composite materials with pyrophosphates as novel negative electrode materials instead of transition metal oxide, are synthesized through simple solid-state reaction. The initial reversible capacity of Mn2P2O7 and Ni2P2O7 are 333 and 340 mAh g-1, and when the composite materials are composed with carbon, the reversible capacity increases to 433 and 387 mAh g-1, respectively. The initial Coulombic efficiency is also improved by about 10%. The Mn2P2O7 and carbon composite material has the highest initial capacity and efficiency, and has the best cycle performance. Mn2P2O7 containing polyanion, has a lower specific capacity due to the large mass of polyanion compared to MnO (manganese oxide). However, since Mn2P2O7 shows a voltage curve with a slope, the charging (lithiation) voltage increases from 0.51 to 0.57 V (vs. Li/Li+), and the discharge (delithiation) voltage decreases from 1.15 to 1.01 V (vs. Li/Li+). Therefore, the voltage efficiency of the cell is improved because the voltage difference between charging and discharging is greatly reduced from 0.64 to 0.44 V, and the operating voltage of the full cell increases because the negative electrode potential is lowered during the discharging process.

Capacity Variation of a Microcell due to Power Control Error in and Overlaid Macrocell/Microcell CDMA System (매크로셀내에 마이크로셀이 중첩된 CDMA 시스템에서 전력제어오차로 의한 마이크로셀의 용량 변화)

  • 강희곡;김영철;노재성;조성준
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.11 no.1
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    • pp.8-17
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    • 2000
  • The BER performance and the capacity variation of a microcell due to power control error(PCE) is analyzed on service types(data and voice, respectively) for the reverse link of an overlaid cell CDMA system. The procedure of analysis is followed as: First, we calculate BER performance according to PCE. Next, we find the minimum SNR for voice service, BER=TEX>$10^{-3}$, and data service, BER=TEX>$10^{-5}$. Then, according to the calculated SNR, we find the maximum capacity of a microcell and macrocell and the capacity of a microcell where interference is considered is found and analyzed with that in perfect power control. We get to the results as follows. The BER performance in 1 dB PCE is similar to that in perfect power control, however, with a increase in PCE, the BER performance is largely degraded. In terms of capacity, it is shown that if the PCE is equal or less than 2 dB, the effect of the PCE on voice service is more than that on data service, but if the PCE is equal or more than 3 dB, effect of the PCE on data service is more than that on voice. Besides, if the PCE is equal or less than 2 dB, both PCE and interference should be considered to calculate the capacity of a microcell, but if the PCE is equal or more than 3 dB, interference can be negligible since the effect of PCE is much stronger than that of interference. Therefore, the microcell should be located where $R_d$, the ratio of a microcell to a macrocell radius, is equal to 0.1, and d, the ratio of the distance between a microcell and a macrocell to the macrocell radius, is equal or more than 0.5, in order to obtain a appropriate microcell capacity against interference. If $\sigma$ is adjusted to less than 2 dB, we may get equal or more than 70% of the maximum microcell capacity.

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The cephalometric study of skeletal types in Cl III malocclusion with reduced lower anterior face height (전하안면 고경이 작은 III급 부정교합자의 골격유형에 관한 두부방사선 계측학적 연구)

  • Han, Dong-Hun;Cha, Kyung-Suk
    • The korean journal of orthodontics
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    • v.26 no.2 s.55
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    • pp.205-218
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    • 1996
  • A given facial type can be considered as a syndrome in which various features are aggregated, so a single parameter is not sufficient to accurately identify a given facial type. This study was designed to identify & characterize the skeletal types that blend under the headline-'Cl III,deepbite'. Cephalograms of thirty-four untreated mixed dentition patients, selected mainly on the basis of clinical impression of Cl III with reduced lower face heights were studied. The following conclusion can be drawn. 1. Cl III malocclusion with reduced lower face height could be classified into three types. 2. Subtype 1 was identified by the following features : strong ramus, more anteriorly positioned upper molars without alveolar hypoplasia, acutely reduced Mn. plane angle. 3. Subtype 2 was characterized by a short ramus, sharply reduced postrior alveolar height, and normal Mn. plane angle. In general, this type had hypoplasia tendency in the vertical dimension. 4. In subtype 3, the AUFH occupying more percentage than ALFH was a outstanding feature. Ramal height was in normal range, alveolar hypoplasia and slightly reduced Mn. plane angle was observed. 5. The features of the subtypes were reflected in certain indices, which can be regarded as discriminative index. LAFH: if reduced, regardless of subtypes, indicates reduced lower ant. face height consistently. FHR: when this ratio is increased, it indicates subtype 1. FHI: when this ratio is in normal range, it indicates subtype 2. FPI: if reduced greatly, it indicates subtype 3.

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The Relation between Mother's LOHAS Propensity and Healthy Dietary Life Attitude perceived by Chinese University Students (대학생 자녀가 지각한 어머니의 로하스(LOHAS) 성향과 건강식생활 태도와의 관련성 연구 - 중국대학생을 중심으로 -)

  • Lee, Yeon-Jung;Ahn, Gee-Jung
    • Culinary science and hospitality research
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    • v.21 no.4
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    • pp.101-120
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    • 2015
  • This study was conducted to examine the relation between a mother's LOHAS lifestyle propensity, healthy dietary life, and nutrient intake perceived by Chinese university students. The subjects consisted of 376 Chinese university students. The research results are summarized below. The mother's LOHAS attitude index was 76.02 points out of a perfect score of 100 points. High LOHAS attitude factors of mothers were 'health', whereas 'social welfare' scored low. The highest LOHAS attitude items of mothers that Chinese university students perceived was 'My mother uses health food, organic food, clean food'(4.26 points). Males who lived on their own in a large city and have normal BMI ($18.5{\sim}22.9kg/m^2$) perceived a high mother's LOHAS score. The highest food habit variables are 'eating without spilling food' 'cleaning up after meals around' and 'washing my hands before meals'. The highest healthy dietary life item is 'I try to maintain a pleasant and enjoyable life'(3.83 points). The highest nutrient intake attitude score is 'I tend to eat yellowish-green vegetables every day.'(3.92 points). According to mother's LOHAS lifestyle score, it was verified that the higher mother's LOHAS lifestyle score, the higher children's food habit, healthy dietary life, and nutrient intake score are. Mother's environment-friendly LOHAS attitude index has a meaningful impact on the child's food habits, healthy dietary life, and nutrient intake.

Radiographic Evaluation of Stiffness of Articular Eminence in the Temporomandibular Joint(TMJ) of Korean Using Dental cone-beam CT (한국인의 측두하악관절에서 Dental cone-beam CT를 이용한 관절융기의 경사도에 대한 방사선학적 평가)

  • Oh, Sang-Chun;Han, Ji-Seok
    • Journal of Dental Rehabilitation and Applied Science
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    • v.29 no.2
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    • pp.163-173
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    • 2013
  • When the mandible performs opening movement, the condyle-disk complex conducts sliding movement along the articular eminence. Thus, anatomic configuration of articular eminence is very important to normal movement of TMJ. The purpose of this study was to measure the posterior slope of the articular eminence and evaluate the effect of a pathologic bone change in the condylar head on the stiffness of articular eminence, and compare the differences of the articular eminence slope by gender and age using dental cone-beam CT. As using i-CAT Cone-Beam Computed Tomography, the CT images of 204 TMJs of 102 patients(43 men and 59 women, mean age: 37.7 years) who were diagnosed at Wonkwang University Sanbon Dental Hospital were evaluated. All images were converted into a TMJ analysis mode to observe the continuous sagittal section images and coronal section images of the joints. To observe and assess bone changes in the condyle, three dentists measured the stiffness of the articular eminence on the same images, and when two of the three dentists agreed on their reading, these results were adopted and recorded. The articular eminence slope, considering the condylar anatomic configuration, was measured in three regions, namely, lateral part, central part, and medial part of the condyle. In the cases of a normal condyle(NCBC) and a condyle(CBC) with bone change, the articular eminence slopes were $57.0^{\circ}$(NCBC) and $51.8^{\circ}$(CBC) at the medial part, $57.9^{\circ}$(NCBC) and $52.4^{\circ}$(CBC) at the central part, and $55.1^{\circ}$(NCBC) and $49.5^{\circ}$(CBC) at the lateral part of the condyle. And the articular eminence slope of the condyle with bone change demonstrated less steepness than that of normal condyle (p<0.05). The articular eminence slope showed mediolaterally that it was the steepest at the central, followed by at the medial, and at the lateral (p<0.05). There were no significant differences by the gender and the age (p.0.05).

A Study on Space Insurance of Foreign nation's Law (외국의 우주보험 관련법 연구)

  • Cho, Hong-Je
    • The Korean Journal of Air & Space Law and Policy
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    • v.26 no.1
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    • pp.271-297
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    • 2011
  • Recently, risk of space accident possibility increased in according to commercial space activity and space debris. It failed launch satellite second times in South Korea. Therefore was discussed on liability and insurance issue. Generally, discuss of space insurance be divided two type. Firstly, space insurance relevant to launching satellite and in-orbit. Satellite Launch Insurance and In-Orbit Insurance by the Satellite Operator Secondly, space insurance relevant to Third Party Liability. The former is to protect owner of satellite and operator. The latter is to liable and indemnify owner of satellite and operator's liability. US, UK, France, Russia, South Korea forced to buy space insurance following to domestic law. This is a brief overview of risk allocation and insurance practices in the commercial space transportation industry today. We begin with traditional space transportation, i.e., commercial satellite launches. This is a mature industry with known players. Industry practices have developed and legislation has been adopted in the U.S. and other countries over the past decades to address liability and insurance issues. The primary focus here is on U.S. law, but the discussion of industry practice applies more generally. We then move on to a more exotic form of space transportation: Commercial human space flight. Several private companies are now signing up space tourists for commercial suborbital human space flight, advertised to become available in the near future. The United States amended its launch legislation in 2004 to promote commercial human space flight. But questions remain as to how this new industry will respond to the risk allocation regime established by the U.S. legislation, which leaves both the space flight operator and space tourist exposed to risk and potential liability. As a general proposition, state statutes and contractual waivers alone cannot be relied upon to provide adequate liability protection, and insurance will be required. Federally mandated contractual waivers by space flight participants or liability caps would be helpful to complement insurance solutions. Eventually, as the industry matures, such practices could be extended to an international legal regime. For all the issues mentioned above, I have studied the existing international treaties and several country's domestic law to the space by referring U.S's Commercial Space Launch Amendment Act of 2004 and concluded that uniform legal regime to govern these insurance issues should be established domestically and internationally in the future.

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International Legal Regulation on Commercial Space Activity (상업적 우주활동의 국제법적 규제)

  • Lee, Young-Jin
    • The Korean Journal of Air & Space Law and Policy
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    • v.28 no.2
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    • pp.183-221
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    • 2013
  • While in the early stages of space activities only a few states engaged in the use of outer space, as is well known, commercial space activities have grown dramatically in recent years. Both states, state institutions, and international governmental organizations as well as many private enterprises are engaged in such commercial use of outer space by now. This development is not reflected in the present state of space law. The existing international instruments of space law were developed and finalized before this development and thus only provide very few and sometimes unfitting provisions for the commercial use of outer space and particularly the use by private enterprises. Law formulated in an era when the word "privatization" had not even been coined cannot contain potential problems caused by the increasing commercialization of outer space. For the promotion and further development of such commercial use of outer space it is necessary to clarify and establish the legal framework for such use, because participants will need this information for their future investments in this field. The purpose of this paper is to research and make an analysis of the contents and international regulation of international space commerce, which is rapidly proliferating and to review the process of improvement on national legislations relating to the commercialization of outer space in a few main space advanced countries to make the sustainable progress of commercial space activities project in international society. The legal implications of matters such as international commercial launch services, the liability aspects of such services, intellectual property rights, insurance, product liability insurance and materials processing could one day will be subject to regulated by international space law as well as domestic law. In fact, the question of commercialization is linked to the question of sharing benefits of space activities, and this currently is an agenda item in the Legal Subcommittee of UN COPUOS. Most of developed countries have enacted the national legislation for commercial space activities relating to the development of our space as follows : The National Aeronautic and Space Act of 1958 and the Commercial Space Act of 1998 in the United States, Outer Space Act of 1986 in England, Establishment Act of National Space Center of 1961 in France, Canadian Space Agency Act of 1990 in Canada, Space Basic Act of 2008 in Japan, and Law on Space Activity of 1993 in Russia. Becides there are currently three national legislations relating to space development and commercial space activities in Korea as follows : Aerospace Industry Development Promotion Act of 1987, Outer Space Development Promotion Act of 2005, Outer Space Damage Compensation Act of 2008. Commercial space great promise for the utilization and expansion of human outer space activities but aspring commercial actors must recognize that foreign policy, as well as obligations to the international community as a whole, ensure that commercial space activities will not operate in a legal and regulatory vacuum. As commercial space matures the law and accompanying regulation will most certainly evolve and choose to become participants in the inevitable evolution of law and regulation.

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Clinical Investigation of 11 Cases of Chronic Eosinophilic Pneumonia Reported in Korea (국내에서 보고된 만성 호산구성 폐렴 11예에 대한 임상적 고찰)

  • Woo, Ka-Eun;Chang, Jung-Hyun;Choi, Young-Ah;Joo, Mi-Soon;Seo, Ki-Youl;Shin, Tae-Rim;Cheon, Sean-Hee;Cho, Young-Joo
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.1
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    • pp.107-115
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    • 1998
  • Background: Chronic eosinophilic pneumonia(CEP) presents with profound systemic symptoms, including fever, malaise, night sweats, weight loss, and anorexia together with localized pulmonary manifestations such as cough, wheeze, and sputum. It is an illness occurring predominantly in women. The chest radiogragh shows fluffy opacities that often have a characteristic peripheral configuration. The hallmark of CEP is the peripheral blood eosinophilia and a prompt response to oral corticosteroid therapy. We investigated characteristics of eleven patients of chronic eosinophilic pneumonia, reported in Korea. Method: There were eleven reports of CEP from 1980 to 1996, including three cases experienced in our hospital. The journals were analysed in respects of clinical history, laboratory, and radiographic findings. Results: 1) Male vs. female ratio is 3 : 8. The peak incidence occurred in forty and fifty decades. The atopic diseases were present in 6 cases. Asthma was the commonest manifestation 2) The presenting symptoms were as follows: cough, dyspnea, sputum, weight loss, fever, general weakness, night sweats, urticaria with the descending incidence. 3) Peripheral blood eosinophilia was present in all patients(mean ; 38.4%) and serum IgE level was elevated in nine patients(mean ; 880IU/ml). Conclusion: The diagnosis of chronic eosinophilic pneumonia is based on classic symptoms, including fever, night sweats, weight loss with a typical roentgenogram of peripheral pulmonary infiltrates and peripheral blood eosinophilia, and that is confimed by lung biopsy and/or bronchoalveolar lavage. Chronic eosinophilic pneumonia is responsive to corticosteroid promptly and recommended at least 6 months of therapy to prevent relapse.

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