• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.136-136
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• 2003

In fiber optic networks, system size and cost can be significantly reduced by development of optical components through planar optical waveguides. One important step to realize the compact optical devices is to develop planar optical amplifier to compensate the losses in splitter or other components. Planar amplifier provides optical gain in devices less than tens of centimeters long, as opposed to fiber amplifiers with lengths of typically tens of meters. To achieve the same amount of gain between the planar and fiber optical amplifier, much higher Er doping levels responsible for the gain than in the fiber amplifier are required due to the reduced path length. These doping must be done without the loss of homogeniety to minimize Er ion-ion interactions which reduce gain by co-operative upconversion. Sol-gel process has become a feasible method to allow the incorporation of Er ion concentrations higher than conventional glass melting methods. In this work, Er-doped $SiO_2$-A1$_2$ $O_3$ films were prepared by two different method via sol -Eel process. Tetraethylorthosilicate(TEOS)/aluminum secondary butoxide [Al (OC$_4$ $H_{9}$)$_3$], methacryloxypropylcnethoxysaane(MPTS)/aluminum secondary butofde [Al(OC$_4$ $H_{9}$)$_3$] systems were used as starting materials for hosting Er ions. Er-doped $SiO_2$-A1$_2$ $O_3$ films obtahed after heat-treating, coatings on Si substrate were characterized by X-ray din action, FT-IR, and N-IR fluorescence spectroscopy. The luminescence properties for two different processing procedure will be compared and discussed from peak intensity and life time.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.135-135
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• 2003

The fast evolution in the fold of optical communication systems demands powerful optical information treatment. These functions can be performed by integrated optical systems. A key component of such systems is erbium doped waveguide amplifier(EDWA). The intra 4f radiative transition of Er at 1.5 $\mu\textrm{m}$ is particularly interesting because this wavelength is standard in optical telecommunications. The fabrication of waveguide amplifier for integrated optics using sol-gel process has received an increasing attention. Potential advantage of lower cost by less capital equipment and easy processing makes this process an attractive alternatives to conventional technologies like flame hydrolysis deposition, ion exchange and chemical vapor deposition, etc. In addition, sol-gel process has been found to be extremely suitable for the control of composition and refractive index related directly with optical properties. The main drawback of such an amplifier with respect to the EDWA is the need for a much higher Er3+ concentration to compensate for the smaller interaction length. However, the high doping of Er might be resulted in the non-radiative relaxation by clustering of Er ions End co-operative upconversion. In order to solve this problem, we investigate the possibility of avoiding short Er-Er distances by encapsulation of Er3+ ions in hosts such as organic-inorganic hybrid materials. For inorganic-organic hybrid sols, methacryloxypropyltrimethoxysilane (MPTS), zirconyl chloride octahydrate and erbium(III) chloride hexahydrate were used as starting materials, followed by conventional sol-gel process. It was observed by TEM that nano sols having core/shell toplology were formed, depending on the mole ratio of Zr/Er. The surface roughness for the coatings on Si substrate was investigated by AFM as a function of Zr/Er ratio. The local environment and vibrational Properties of Er3+ ions were studied using Near-IR, FT-IR, and UV/Vis spectroscopy. Nano hybrid coatings derived from polymer and Er doped encapsulation Eave the good luminescence at 1.55$\mu\textrm{m}$.

• Journal of Society of Preventive Korean Medicine
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• v.13 no.3
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• pp.29-41
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• 2009

Objectives : This study was performed to compare consciousness of doctors on cooperative practices of western medicine and traditional Korean medicine, and to provide policy implication for development of cooperative practices. Methods : The structured questionnaires were mailed to 132 doctors working in non-cooperative practicing university hospital and 77 doctors working in cooperative practicing hospitals in Busan metropolitan city. The response rate was 40.2% and 40.3% respectively. This survey was performed from 10 Oct. 2008 to 31 Oct. 2008. Results : The doctors working in general hospital had comparatively negative consciousness on basic concept, value and necessity for cooperative practices and traditional Korean medicine. In regards with disease treatment's effectiveness of cooperative practices, both groups evaluated musculoskeletal and immune disease were more effective than others. There were positive relationships between perception for cost-effectiveness and consciousness on intention to participate cooperative practices(p<0.05). Also doctors who experienced traditional medicine treatment had positive consciousness on cooperative practices(p=0.05). Conclusions : To activate cooperative practices of western medicine and traditional Korean medicine, some efforts should be carried out. These include promoting cooperative education programs in medical schools and traditional Korean medical schools, doing research on cost-effectiveness of cooperative practices, and trying to minimize legal and systemic restrictions for cooperative practices.

• Journal of Korean Library and Information Science Society
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• v.8
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• pp.155-184
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• 1981

The publication of the result of scholarly research is an integral part of the process by which learning is advanced. The university presses, as one of the major scholarly publishers are now confronted with many critical problems, such as the declining unit sales, the explosion of manuscripts, the challenge of new publishing technologies, etc., in performing the role of the scholarly communication system. The purpose of this study is to identify the problems imposed on the university presses and alternative strategies for them. For the study, the related literature to the subject were read, analyzed and synthesized, from which the overall prospect of the problems and alternative strategies are derived. The conclusion of the study can be summarized as follows: (1) The faith of the university should lie in its role to advance scholarly learning through production and dissemination of high-quality knowledge, and the university press should materialize such a faith. (2) The scholarly books, though not the best media of scholarly communication taking a side view of its timeliness and brevity, can perform the function of the best media for the specific subject and readers. (3) The scholarly books as national resource must be published for the scholars demanding them even though the publication can't help depending on the subsidiary fund. (4) For the survival and activation of the university presses, the following strategies should be examined, and put in force if necessary. (a) The role of the foundation su n.0, pporting the university presses should be expanded (b) The Co-operative system among the operations of the presses should be established. (c) It is desirable that the university without the press should participate in the university with the press for both the financial su n.0, pporting and the publicizing its faculty's manuscripts. (d) The positive efforts should be made for the increase of sales copies by implementing the dual-system of publication. (e) It is desirable that 'recording system' should be incorporated in the traditional publication system both for the lightening of financial problems and the explosion of publications. (f) It is necessary that the effective methods of the bibliographical control should be developed for the improvement of the scholarly communication. (g) Any kind of the permanent organization composed of the representatives from all the infrastructures of information industry should be established to study the character and direction of technological changes and to discern the better choice of specific, technologies in the scholarly communication system.

• Journal of Korean Society on Water Environment
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• v.18 no.3
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• pp.253-260
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• 2002

The purpose of this research was to describe the mechanisms and prevention of initial degradation in turbidity of the sand filter effluent. The method used was by adding a coagulant (PAC) to the sand filter after backwashing as a means of reducing turbidity. It was found that adding 80 mg/L of PAC solution to the sand filter was very effective in improving the initial effluent turbidity. A turbidity removal efficiency of 99 % was observed in the initial term period as compared to a 70% efficiency without PAC addition. The PAC solution added to the sand filter resulted in high aluminum concentration at the upper layer as compared with the bottom layer of the sand filter column. A change in the zeta potential to a strong positive-ions at upper layer was observed at this time but only a small change was obtained at the bottom. This result showed that the zeta potential of the sand was changed to positive with PAC coating. The effect of pH on zeta potential with PAC addition was also investigated. Zeta potential was greatly changed to positive-ion at pH 4~6. A series of experiments was then conducted in this study to optimize the pH of the PAC solution to be added to the sand filter after backwashing. The removal efficiency of turbidity was found to be highest at pH 5. This result suggested that hydrolyzed aluminium species attached to the surface of the sand enhanced the removal of turbidity of the effluent.

• Journal of Society of Preventive Korean Medicine
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• v.14 no.1
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• pp.37-48
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• 2010

Objective : The purpose of this research was to provide basic data for developing the collaborating care of Korean traditional medicine and western medicines by analyzing the perceptions of residents visiting local health centers on the collaborating care. Method : To this end, a self-administrated questionnaire was surveyed to 417 participants from March 10 to March 19, 2005. The questionnaires were regarding medical preferences, effectiveness, co-operative treatment types, and the demographic characteristics of the study population. The main statistical methods employed for analysis were frequency chi-square test analysis, using SPSS system 12.0 software for Windows. Result : First, the perceptions of collaborating care, such as preference and effectiveness, were better for residents who had experienced Korean traditional medicine(p < 0.05). Second, the most favorable collaborating care type was the neuromuscular disease and rehabilitation, and in particular, the preference of the patient who had experienced Korean traditional medicine was much higher than those who had not experienced it(p < 0.05). Third, as for recognizing the future of collaborating care, respondents insisted that collaboration care has to be conducted under evidence-based research. The reasons why collaborating care has not been active were reported as "difference in solving disease problems between oriental medicine and western medicine." The most important role of the Korean traditional medicines in the public sector was to provide specialized service for the elderly and low income households. Conclusion : Most respondents expected the positive effects of the collaborating care and wanted it to develop, particularly for neuromuscular diseases. As for the health promotion program in health centers, it was more popular than the home visiting program for the elderly and preventive rehabilitation for stroke. Now we must plan to balance between the need of the community and the medical provider on collaborating care.

• Journal of Society of Preventive Korean Medicine
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• v.15 no.1
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• pp.131-143
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• 2011

Objective : The purpose of this study was survey about the recognition and demand on cooperative system between western and oriental medicine of stroke patients in National Rehabilitation Center. Methods : The participants were 205 stroke patients in the National Rehabilitation Center and investigated the recognition and demand on cooperative system between western and oriental medicine. Results : As to general characteristics of the group, 56.9% were male, 30.7% were in the 60~69 age, 24.3% of patients had an average income per month 1.0~2.0 million. In regard to disease status of patients, 53.8% were cerebral infarction, 35.8% were below 6 month in disease duration, 73.7% were none recurrence, 52.8% were hypertension as related disease, 74.5% were motor paralysis sequela. 83.2% were positive response in using oriental medicine department of National Rehabilitation Center. The most wanted therapy was acupuncture. Most of respondents expected that co-operative treatments were to be improving the cure effect for patients. And they wanted cooperative system combined evenly between western and oriental medicine, so the western doctors and the oriental doctors suggest the plan giving lots of medial benefits for patients. Conclusion : This survey showed the recognition and demand on cooperative system between western and oriental medicine of patients in National Rehabilitation Center. It is possible to realize patient's centered treatment under the stable and efficient cooperation of western and oriental medicine.

• Journal of The Korean Society of Grassland and Forage Science
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• v.4 no.2
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• pp.152-157
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• 1983

This study was carried out to investigate changes in the quality and botanical composition of native pasture during the grazing period. The results obtained were as follows: 1. On all the farms, the total dry matter yield of native pasture was much higher in the October-cut than in the July-cut. 2. The crude protein content was higher in the July-cut than in the Oct.-cut, while the crude fiber content gave opposite results. There was the same tendency on all the farms. 3. When the six farms were compared, the highest crude protein content was found at Hawon and Haian farm, and cows on these farms showed the highest daily weight gain. Ohra farm had the lowest crude protein and the cows on this farm the lowest daily weight gain. 4. The botanical composition of the main species distributed was 58.1% Zoysia japonica, 16.4 Pteridum aquilinum, and 3.8% Miscanthus sinensis. In the case of family, 72.1% were Gramineae, 1.8% Leguminosae, and 16.4% Pteridacea. 5. According to botanical composition of a family, Hawon farm had the highest daily weight gain and the highest rate of Gramineae and Leguminosae. Ohra and Youngkang farms had the lowest weight gains, but the native grassland on these farms contained a high proportion of Pteridum which is toxic to cattle.

• Korean Journal of Veterinary Research
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• v.43 no.2
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• pp.219-230
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• 2003

Porcine epidemic diarrhea virus(PED), a member of Coronaviridea, is the etiological agent of enteropathogenic diarrhea in swine. The purpose of this study was to investigate genetic characteristic of PEDV isolated in Korea. Nucleocapsid(N) gene and membrane (M) gene of recent Korean PEDV strains isolated in 2001 were amplified, cloned, sequenced and analyzed. N gene of seven Korean PEDV field isolates bad 94.5% to 99.4% nucleotide and 92.4% to 99.4% amino acid sequence homology each other. Nucleotide and amino acid sequences of Korean field PEDVs were different from published foreign PEDVs, showing 95.1% to 98.0% nucleotide and 93.5% to 97.6% amino acid sequence homology. By phylogenetic tree analysis on based nucleotide sequences, PEDVs were clustered into four groups. By phylogenetic tree analysis based on amino acid sequences. PEDVs were clustered into five groups. M gene of our Korean PEDV field isolates had 99.6% to 100% nucleotide and 98.7% to 100% amino acid sequence homology each other. Nuclotide and amino acid sequences of Korean field PEDVs were different from published foreign PEDVs, showing 98.5% to 98.8% nucleotide and 97.3% to 97.8% amino acid sequence homology. By phylogenetic tree analysis based on nucleotide and amino acid sequences, PEDVs were clustered into two groups which were Korean PEDV isolate group and foreign PEDV isolate group.

• The Journal of Fisheries Business Administration
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• v.48 no.3
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• pp.15-32
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• 2017

This article's aim is to review the jurisprudence which has emerged pursuant to the international dispute settlement provisions and to provide a provisional expectation as to the future of international dispute settlement under "UNCLOS". Globally, marine fisheries play an important role in ocean biodiversity and the food security of millions of people, providing a vital source of high-quality dietary protein and supporting individuals' livelihoods and income. In the 1982 Convention, the establishment of co-operative mechanisms for effective monitoring, control, surveillance and enforcement, decision-making procedures facilitating the adoption of such measures of conservation and management, and the promotion of the peaceful settlement of disputes are called for. In this study, 'Northeast Asian Sea' means that the Yellow/East China Sea, the East Sea, the Ohotsk Sea, the Kamchaka Sea, the Alaska Sea, and the Bering Sea surrounded by Korea, China, Japan, Russia, U.S.A. and Canada including their EEZs. There are several bilateral fisheries agreements existing in Northeast Asian area, the Fisheries Agreement between Republic Korea and Japan, between Republic of Korea and China, between China and Japan, between Republic Korea and U.S.A., between Republic Korea and Russia, between Russia and Japan, And there are several regional fisheries organizations existing in Northeast Asian area, for example NPAFC(Convention for the Conservation of Anadromous Stocks in the North Pacific Ocean), CBSPC (Convention on the Central Bering Sea Pollack Conservation), PICES(North Pacific Marine Science Organization), NPFC(North Pacific Fishery Commi-ssion) etc. It analyzed the proliferation of bilateral treaties and multilateral treaties due to the adoption of the EEZ in Northeast Asia reviewed the strengthening of management rights on the high seas marine living resources and marine environment preservation of regional fisheries organizations. In view of the changes in the international fisheries mechanism this paper suggested the future direction of the country in overseas fisheries. We concluded as follows. We shall apply bilateral treaties first, regional fisheries organizations' treaties secondly, and provisions under "UNCLOS" for dispute settlement last.