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Rate of Sediment Accumulation and Geochemical Characteristics of Muddy Sediment in the Central Yellow Sea (황해 중앙부 해역 니질 퇴적물의 지화학적 특성 및 퇴적률)

  • 윤정수;김여상
    • The Korean Journal of Quaternary Research
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    • v.16 no.1
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    • pp.1-16
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    • 2002
  • A total of 4 muddy sediment samples collected from the Central Yellow Sea were analyzed for chemical composition. The results are compared with the previously published Huanghe, Changjiang and Keum River geochemical data in order to understand provenance and sedimentation of fine-grained mud, and the sediment accumulation rates estimated. The sandy sediment facies is distributed in the eastern area, a patch of fine-grained mud exists in the western central prat, and the sandy mud and clay sedimentary facies shot. north to south zonal distribution in the central region. The content of calcium carbonate ranges from 2.8 to 10.5%, and its distributional trends to be more concentrated on the western muddy sediments near toward the China side rather than on the eastern sandy sediments. The accumulation rates obtained using Pb-210 geochronologies for the muddy sediments in the Central Yellow Sea showed ranges from 0.21 to 0.68 cm/yr or 0.176 to 0.714 g/$\textrm{cm}^2$. yr. The sedimentation rate from core CY96010 located in the eastern near side of Shandong Peninsula which is affected by the Huanghe River shows 0.68 cm/yr or 0.714 g/$\textrm{cm}^2$ . yr. The sediment cores CY96008 and CY96002 in the Central Yellow Sea, the estimated of sediment accumulation rates shows 0.21~0.23cm1yr or 0.176~0.220 9/$\textrm{cm}^2$.Vr respectively, which are much lower than above samples. These indicate that the muddy sediments in central area of the Yellow Sea may have received influence of the sediment discharge from the Huanghe River. The concentrations of Ca, Na, Sr, Ho, La, Tb, Ta and Ca/Ti ratio of the muddy sediments in the Central Yellow Sea are higher than those of the Changjiang sediments and lower than those of the Huanghe sediments. However, these element values showed similar concentration patterns than those of the Huanghe sediment. The element contents such as Fe, Ti, Nl, Co, Cr, Cu, Pb, Sc, Ce, Nd, Sm, Eu, Cd and Dy in the study area are higher than those of the Huanghe sediments and lower than the Changjiang River sediments, but these values showed close to resemblance content trends those of the Changjiang sediment. The concentration of Mn, K and Sr in sediments of the study area are similar to those of the Keum River and eastern Yellow Sea sediment. They are rich in Zn, Rb, Cd, U, Cs and Li than those of the other comparison legions. Therefore, the terrigenous materials sources of the muddy sediment in the Central Yellow Sea comes mainly from Huanghe River in the past and present, and also have party derived from the Changjiang and Keum River, while the biological deposit in this area are carried by the Yellow Sea Warm Current.

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A Feasibility Study on Thermal Energy Resource in Deep Ocean Water (해양심층수 에너지자원 이용 타당성 분석 연구)

  • Kim, Jeong-Hyop;Kim, Gwang-Tae;Park, Se-Hun;Oh, Wee-Yeong;Kim, Hyeon-Ju
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.15 no.1
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    • pp.9-18
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    • 2012
  • Annual power consumption of our country is positioned in the upper percentile in the world, and because the proportion of fossil power generation is high, which ranks the 10th $CO_2$ emission country. In this regard, government has established and is implementing the National Energy Basic Plan to realize to get out of fossilization in energy supply while focusing on securing the technology for renewable energy as well as its commercialization in order to reduce greenhouse gas. Resource recovery technology for deep seawater thermal energy which is one of renewable energies is newly getting attention domestically as well as in overseas for securing resources and environmental improvement as a core technology for multilateral use of marine resources for low carbon and green growth. Economic feasibility analysis was conducted for the research and development as follows on the use of ocean thermal energy conversion and seawater air conditioning. First, in the case of power generation using deep seawater and warm discharge water from ocean thermal energy conversion plant of 1MW level, it is judged that the economic feasibility is insufficient but the feasibility will be significantly improved if we consider not only power generation but also drinking water and certified emission reduction by developing the power plant to the size for commercialization. Second, the economic feasibility for the use of deep seawater as air conditioning for the power plant of 1,000RT level turned out to be very good. Especially, when we consider certified emission reduction, it will be possible to secure sufficient economic feasibility. When we use it in connection with ocean thermal energy conversion, water conversion and agricultural and fishery use, it is judged that economic ripple effect will be significant and therefore it will be necessary to conduct research and development for early commercialization, distribution and diffusion of deep seawater energy.

Staged Fontan Operation Via Bidirectional Glenn Operation (양방향성 GLENN 수술을 통한 단계적 FONTAN 수술의 임상분석)

  • 한재진;김웅한
    • Journal of Chest Surgery
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    • v.30 no.11
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    • pp.1062-1068
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    • 1997
  • From August 1989 to January 1996, a total of 105 cases of bidirectional Glean operations have been done as the interim stage for the patien s with some risk of univentricular correction at Sejong General Hospital. From December 1992, we started the conversion to Fontal operations for them, and 42 cases underwent Fontal-stage operation till February 1996. Their diagnoses were univentricular heart in 19(right ventricular type : 14), tricuspid atresia 11, double outlet of right ventricle 9, and others in 3 cases. The median age of bidirectional Glerln-stage operation was 12.5 months(range 2 months to 8 years) and Fontan-stage operation was at 59.6 months of median age(range 1 year 5 months to ,9 year 7 months). The mean waiting interval between the two operations was 33.88 $\pm$ 17.85 months with a range of 10 months to 6 years 3 months. During the waiting periods, 18 patients developed significant systemic-pulmonary collaterals andfor systemic verso-veno collateral channels. There were 5 hospital deaths after operations due to low cardiac output in 4 and sepsis in one. Most of the Fontal-stage operations were done by the late al tunneling with Core-Tex tube graft patch and fenestrated with the size of 2.5 ~6 mm. All the patients were followed-up(7 months to 4 years 2 months, mean 21.97$\pm$10.82 months) and there were 5 late deaths(postoperatively 6 months to 2 years) due to thromboembolism in 1, after heart transplantation 1, plastic bronchitis 1, protein loosing enteropathy 1, and pneumonia in 1. Dividing the patients by the waiting interval of 2 years, the early correction to Fontal group (N=16) showed the better results(hospital mortality 1116, late mortality 1116, significant collateral development 2/16) compared to the other group(N=26) (4/26, 4/26, 16/26). In conclusion, after the bidirectional Glean-stage operation successfully got rid of the previous risk factors, we recommand to do the Fontan-stage operation no later than 2 years of interval.

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Comparison of Growth, Yield and Quality by Green Crop Treatments in Rice (Oryza sativa L.) Organic Cultivation (벼 유기재배 시 녹비작물 처리에 의한 작물의 생육, 수량 및 품질 비교)

  • Cha, Kwang-Hong;Oh, Hwan-Jung;Park, Heung-Gyu;An, Kyu-Nam;Park, Ro-Dong;Jung, Woo-Jin
    • Korean Journal of Organic Agriculture
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    • v.19 no.1
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    • pp.55-64
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    • 2011
  • To investigate a comparison of rice yield and quality by a utilization of green crops using barley and hairyvetch, this study was carried out in rice (Oryza sativa L.) organic cultivation field. Convention barley harvest (CBH), Green barley crop (GBC), Green barley+Green Hairyvetch crop (GB+HVC), and Non-Green crop (NGC) were treated in rice cultivation field. The results obtained as following: 1) Culm length and pancile length in Convention barley harvest (CBH) cultivation were longer than organic cultivation but were not significant difference in all treatments. Yields of milled rice in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were by 90.3% and 95.9%, respectively. 2) Protein contents in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were by 5.7% lower than 6.6% in Convention barley harvest (CBH) cultivation. Amylose contents in all treatment were similar as range 18.8% to 19.1%. Whiteness contents in Green barley crop (GBC) and Green barley+Green Hairyvetch crop (GB+HVC) were slightly higher by 38.9% and 39.1%, respectively, than 37.7% in Convention barley harvest (CBH) cultivation. 3) Palatability values in Barley harvest (BH) and Non-Green crop (NGC) were slightly higher by 82.0 and 83.8, respectively, than 77.6 in Convention barley harvest (CBH) cultivation. 4) Head rice in Non-Green crop (NGC) was 95.5%, while that of Convention barley harvest (CBH), Green barley crop (GBC), and Green barley+Green Hairy-vetch crop (GB+HVC) were slightly low as range 93.8% to 94.2%. White core and belly rice in Convention barley harvest (CBH) cultivation was the highest level by 1.7%. 5) Leaf blast, neck blast, sheath blight, rice stem maggot, rice leaf roller, rice leaf-tier, and green rice leafhopper were occurred lightly in rice field.

Morphology, Mineralogy and Genetic Implication of Placer Gold from the Huongkhe Area, Vietnam (베트남 홍케 지역 사금의 산상과 생성연구)

  • Choi, Sang-Hoon;Choi, Seon-Gyu;Han, Jin-Kyun
    • Economic and Environmental Geology
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    • v.29 no.3
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    • pp.235-246
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    • 1996
  • Placer gold in collected heavy minerals from several localities in Huongkhe area, is consistently very finegrained (${\leq}100$ to $400{\mu}m$). The size and size distribution show somewhat differences at Dongdo and Hoahai : at Dongdo, predominant relatively larger and wide distribution; at Hoahai, characteristic relatively finer and narrow distribution range. The morphology of gold grains is divided into the four groups assumed by the dimension ratio : spherical, subprismoidal, prismoidal, and irregular. The gold grains at Dongdo show wide morphological distribution, whereas, at Hoahai, spherical form is predominant (${\approx}75%$). Three main types of gold are classified based on their chemical composition and mode of occurrence: type I (electrum; fineness=568~931), type II (amalgam; fineness=671~927), and type III (native gold; fineness=923~999). Type I gold contains, relatively high and variable silver contents (${\approx}11$ to 58 atomic % Ag), and has been classified into two subtypes based on their silver contents (type IA, ${\approx}11{\sim}39$ atomic % Ag; type IB, ${\approx}40{\sim}58$ atomic % Ag). However, type I gold would have been generally original compositions of electrum which originated at the provenance deposits. Mercury reacts with gold and silver to form amalgam (type II gold) which has variable Hg contents (1.2~30.5 atomic % Hg). The mercury contents in gold grains at Hoahai (10.9~30.5 atomic % Hg) are higher than those at Dongdo (5.8~21.1 atomic % Hg). The gold grains from the area generally exhibit a high-purity gold (type III) rim. The individual rims on the various grains range from <1 to $80{\mu}m$ in thickness and have silver contents of <10 atomic percent Ag, even though the core compositions range from ${\approx}11$ to 58 atomic percent Ag. The rim of gold most likely is responsible for the commonly cited cases of gold from placer deposits assaying at higher values of fineness than the gold in the corresponding source lode. The gold-rich rim in the Huongkhe area apparently forms by a combination of self-electrorefining and preferential dissolution of silver under oxidizing nature during the weathering and transport process. All data of gold grains in the Huongkhe area suggest that the transport distances and/or time of placer gold at Hoahai are generally farther than those at Dongdo. The mercurian gold bearing provenance deposits at Dongdo and Hoahai would be suggest nearest epithermal gold-silver vein-type.

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Association Between the Polymorphism on Intron 5 of the Lipoprotein Lipase Gene and Carcass Traits in Hanwoo (Korean cattle) (한우 Lipoprotein Lipase 유전자 Intron 5번의 Polymorphism과 경제 형질과의 관련성 분석)

  • Lee, H.J.;Lee, S.H.;Cho, Y.M.;Yoon, H.B.;Jeon, B. K.;Oh, S.J.;Kwon, M.S.;Yoon, D.H.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.947-956
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    • 2004
  • The primary role of lipoprotein lipase(LPL) is the hydrolysis of triglycerides(TG) from the core of triglyceride-rich lipoproteins such as chylomicrons and very low density lipoproteins in plasma. Fatty acids liberated by LPL on capillary endothelial surfaces are available for tissues as energy sources especially in muscles or for storage in the form of TG in adipose tissues. Therefore, as the candidate gene related to the carcass traits of the beef cattle, we have directly sequenced the exon 5${\sim}$exon 6 region in the bovine LPL gene for discovery of single nucleotide polymorphism(SNP) with 24 unrelated Hanwoo(Korean cattle). Novel eight sequence variants were detected: three loci on exon 5, three on intron 5 and two on exon 6. All SNPs identified were strongly linked each other, and one hundred twenty eight Hanwoo samples were genotyped one SNP on intron 5 using PCR-restriction fragment length polymorphism method by digestion with Hae III restriction enzyme. The allele frequency of the polymorphism was 0.76 and 0.24. The effects of this polymorphism on the breeding values of the carcass weight, loin muscle area, back fat thickness and marbling score were analyzed using least square methods of SAS GLM. The marbling score of BB genotype was significantly higher than those of AA and AB genotypes(P<0.05). This result indicates that this polymorphism may be associated with the variation of marbling score. Further study is warranted to investigate the phenotypic association in Hanwoo.

Effect of Irradiation and Packaging Methods on the Oxidation of Cholesterol in Raw and Cooked Chicken Leg Meat (방사선 조사 및 포장방법이 생계육 및 조리계육의 콜레스테롤 산화에 미치는 영향)

  • Lee, J.I.;Shin, T.S.;Jin, S.K.;Kim, I.S.;Kim, Y.H.;Joo, S.T.;Park, G.B.
    • Journal of Animal Science and Technology
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    • v.45 no.5
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    • pp.825-834
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    • 2003
  • Chicken thigh from a retail market were used as experimental samples. Some chicken samples of raw state were packaged with PVDC at an aerobic and vacuum condition. The other samples were cooked until core temperature arrived at 70$^{\circ}C$ and then packaged immediately in the same way of raw samples. After samples were irradiated by electron beam at 6 kGy, they were stored in a refrigerator. Identification and quantity of cholesterol oxides were made at 0 and 7 days of storage, respectively. During the early stage of storage, 7$\beta$-hydroxycholesterol, $\alpha$,$\beta$-epoxide, cholestanetriol and 7-ketocholesterol were produced from the raw meat samples, and the production of these chemicals were significantly higher(P〈0.05) from the samples with aerobic packaging than those with vacuum packaging. With storage time, 7$\alpha$-hydroxycholesterol, 6-ketocholesterol and some other chemicals, which were not found during the early stage of storage, were found. Also, the formation of these chemicals were significantly increased(P〈0.05) with storage time. Cholesterol and lipid oxidation products of cooked meat after irradiation and irradiated meat after cooking were significantly increased(P〈0.05) with storage time for all treatments, and vacuum packaging results in showed significantly lower value(P〈0.05) than aerobic packaging. Summarizing the aforementioned results, it was found that the formation of cholesterol and lipid oxides and lipid oxidation was more easily affected by packaging condition than irradiation.

A Critical Approach on Environmental Education Biased to Environmental Possibilism - From Clearing up the Cause to Problem-Solving Mechanism - (환경관리주의 환경교육에 대한 비판적 고찰 - 원인규명에서 해결기제로의 전환을 위하여 -)

  • Kim, Tae-Kyung
    • Hwankyungkyoyuk
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    • v.18 no.3 s.28
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    • pp.59-74
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    • 2005
  • We can't deny Korean EE has basically developed on the basis of Environmental Possibilism (Environmental management or Reformism) in lots of aspects. I would show three representative proofs here, the first, the philosophy of Korean EE has been mainly focused on dichotomy of human-techno centrism and eco-centrism with no considering other alternative environmentalism since 4th Formal Curriculum, 1981. The second, simultaneously, the concept of EE has not distinguished from it of Science education. (Furthermore, unfortunately some says EE has been a part of Science education, although there should be many differences on its contextual aspect.) And the third one is that the limit of possibilism which market economists have worried, has scarcely mentioned in various kinds of EE-related teaching materials. Possibilism is basically likely to be accompanied by science and economics-oriented approach, and in this aspect this dichotomy, human-techno centrism and eco-centrism, has come from perspectives of Economical development process and over-addicted belief to Science. So it is enough to say that Korean EE has basically developed with biased to Environmental possibilism, in other words, biased to preference to it. And I'll critically focus on these two axes of possibilism, Science and Economics and its dichotomy. Of course, we should accept there are so many same parts in its contents between EE and Science, but we should know its contextual differences for triangular position of environmentalism suitable to EE and also overcome science-dependant approach to EE. Although science-dependant approach to EE and dichotomy could provide some tools for clearing up the causes of environmental problem, especially always it has insisted fundamental causes of environmental problem originated in human faults and over-use of eco-source or over-economic development, but now it is old-fashioned discourse, furthermore it come to have unavoidable limits in the debates of problem-solving mechanism to environmental problems. The paramount important thing is to supply the ways or thoughtful mechanism for solving or coordinating the Environmental problems, not just searching for cause of it. But scientific approach and its dichotomy based on possibilism have continuously born cause & effect in EE-related discourse. So there are so much needs to transfer from continuous bearing of cause & effect to constructive alternatives at least in environmentalism of EE. Traditionally, dichotomical division in EE Environmentalism, human-techno centrism and eco-centrism, couldn't have Provided any answers to our real society, it just gives us only cause & effects of Environmental problems. And also we can't find the description on the limits of capitalism market approach to Environmental problems especially in Korean EE text books, other teaching materials and its teaching-learning process, although market approach economist has been proved its fault beyond its functional merits as Environmental management tools. So we should introduce other alternative Environmental philosophy instead of Possibilism such as eco-socialism insisted by Schmacher M. and Boochin etc, or marxist-environmentalism for relative and comparative views to market-thought such as commodification. In this aspect we need to accept Oriental philosophy based on moderation(中庸) as new another alternatives with the reflection that we have recognized monism as representative Oriental philosophical environmentalism. Fundamentally monism has done its role with providing relative concepts to Dichotomy Enlightenment, but we can't say it has been core concept for understanding of oriental environmentalism, and we can't distinguish monism from oriental philosophy itself, just because oriental thought itself was basically monism. So conceptual difference should be recognized between EE and Science education in teaching-learning process on the basis of life-philosophy(Philosophie des Lebens) from epistemology. For this transformation, we should introduce existentialism in Science education, in other words, only existential Science education based on phenomenology or interpretivism can be EE. And simultaneously we need some ways for overcoming of scientific foundationalism which has been tradition making science not stand on existentialism, formulating and featuring of almost all of natural things and its phenomenon from after enlightenment in western world, but it has malfunctioned in fixing conception of science just into essentialism itself. And we also introduce integrated approach to science and society for EE like STS. Those are ways for overcoming of Environmental possibilism in EE.

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Study on the viewpoint of the balance(平衡觀) on the 'Sanghan prescription(傷寒方) throughout the academic sources of 'Sang Han Lon' (상한론(傷寒論)의 학술연원(學術淵源)을 통(通)한 상한방(傷寒方)의 평형관 고찰)

  • Kim, Ji-hyung;Park, Sun-Dong
    • The Journal of Dong Guk Oriental Medicine
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    • v.4
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    • pp.25-52
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    • 1995
  • 'Sang Han Lon' became the sources for treatment and prescription in the Oriental medicine. After that, for some 1800 years the various writings for studying in many ways more than 1000 books which many old sages really intended to inquire into and study the value of books. It is considered that it is the result which the old sages tried to grope for many-sided directions in order to understand 'Sang Han Lon'. In this study, I tried to inquire into prescription and its relevant medicinal substances, that is to say, the crystalization of the physiology, pathology and treating method on the basis of the academic sources of his thoughts. The method to approach is "from what basis of thought system was 'Sang Han Lon' derived first of all?" Secondly, how was the thought system, which became the basis of 'Sang Han Lon', applied to concretely? I studied on the basis of the above important two problems. It is well known to everybody that 'Sang Han Lon' succeeded to the tradition of Naekyung(內經) as well as Cwuyek(周易, Chinese classic on divination). Besides, I inquired into and arrived at conclusion as follows that how the viewpoint on the balance(平衡觀), which was one of the common point between. Cwuyek(周易) and medical science in case of the 'Sanghan prescription'(傷寒方), was applied to concretely. 1. In naming, it is considered that from the same interconnection which the common point with Cwuyek(周易) was the same as obtaining the imigination(取象), the imagination was obtained and was named. 2. In case of being concerned in the gastro-intestinal track, namely, the core of the balance and harmony with the balance and harmony being emphasized, '理中'(It implies 'taking care of gasstro-intestinal track')" and '建中'(It implies 'establishing of gastro-intestinal track'), that is to say, '中'(It implies 'taking care of' & 'establishing of gastro-intestinal track') was emphasized much more. 3. In case of treatment taking advantage of three kinds of medicine in draught, powder and pills in the prescription, while treating during adjusting the slowness and fastness, I maintained the harmony not to damage the righteousness(正氣). 4. In case of the prescription, when exhaling(發散), astringing(收斂), loosing bowels, protecting the gastro-intestinal track and vomitting, he used the medicinal sustances in order to protect the gastro-intestinal track and treated not to damage the righteousness. 5. Especially, in case of the prescription in order to adjust the negative and positive principle of inside-outside(素囊陰陽), he composed of medicinal substances relevant to hot, cold, spicy and sour(寒熱辛酸) in conformity with the prescription and I paid much more attention to the one-sided treatment. Considering the various prescriptions, it is regarded that the adjusting prescription is kept its balance. 6. In the way of processing the medicinal substances in order to change effect of medicine in conformity with the reenactment, he tried to plan the balance of '一升一降' with the decrease of RHEI RADIX ET RHIZOMA(大黃) and increase of wine. 7. In boiling the medicine, he boiled the composed medicine in the time sequence for the purpose of adjusting the slowness and fastness and adapted to harmony of the negative and positive principle(陰陽調和) on the essence function(體峻用純). 8. In taking medicine, he tried to reduce the time of taking the medicine in case of being boiled slowly and tried to increase the dosage and eventually he planned the balance of one time slowness and one time fastness. As I inquired into the above result, a few steps for protecting method to boil the relevant medicinal substances, how to take the medicine and how to process the composed medicinal substances in order to change the effect of medicine can make the human body, which the disease penetrate into, go forward to the righteousness(正氣) and what is much beter, it is considered that this protecting method can be a carefully considerable one in order to protect the righteousness and can subdue the disease, not to damage the gastro-intestinal track and there can exist the viewpoint of balance(平衡觀) on its core.

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CNT-Ni-Fabric Flexible Substrate with High Mechanical and Electrical Properties for Next-generation Wearable Devices (차세대 웨어러블 디바이스를 위한 높은 기계적/전기적 특성을 갖는 CNT-Ni-Fabric 유연기판)

  • Kim, Hyung Gu;Rho, Ho Kyun;Cha, Anna;Lee, Min Jung;Ha, Jun-Seok
    • Journal of the Microelectronics and Packaging Society
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    • v.27 no.2
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    • pp.39-44
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    • 2020
  • Recently, numerous researches are being conducted in flexible substrate to apply to wearable devices. Particularly, Conductive substrate researches that can implement the wearable devices on clothing are massive. In this study, we formed fiber substrate spraying CNT and Pd mixed solution on it and plated metal layer with electroless plating. Used SEM equipment and EDS analysis to analysis structure of the plated fiber substrate and discovered Ni layer was created. For check electrical properties, mapping was performed to check surface resistance and distribution of resistance of electroless plated fiber substrate with 4-point probe. It was confirmed that conductivity was improved as the duration of electroless plating was increased, and it was found that distribution of resistance by surface location was uniform. Changes in resistance due to mechanical stress were measured through tensile, bending, and twisting tests. As a result, it was confirmed that resistance change of flexible substrate gradually disappeared as plating time increased. Using UTM (Universal testing machine), it was analyzed mechanical properties of the electroless plated substrate with respect to changes in plating time were improved. In the case of conductive fiber substrate in which electroless plating was performed for 2 hours, tensile strength was increased by 16 MPa than fiber substrate. Based on these results, we found that Ni-CNT-Fabric flexible substrate is adequate for clothing-intergrated conductive substrate and we positively expect that this experiment shows flexible substrate can adapt to and develop not only a wearable device technology but also other fields needing flexibility such as battery, catalyst and solar cell.