• Asian Journal of Turfgrass Science
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• v.22 no.2
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• pp.149-160
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• 2008

This study was carried out to examine the growth performance of 10 cultivars of creeping bentgrass under salt injury in Seo-san reclaimed area. Turfgrass performance studies included 10 creeping bentgrass cultivars (T-1, L-93, Penn A1, Pennlinks II, Seaside II, Declaration, Penn A4, Crenshaw, Dominant, and Penncross). Ten creeping bentgrass cultivars were grown on a USGA recommended research green. Plots were seeded on May 31, 2006 at the rate of $7\;g{\cdot}m^{-1}$. Electric conductivities of irrigation water (ECw) and soil (ECe) were ranged from 0.28 to $3.3\;d\;S{\cdot}m^{-1}$ and from 0.25 to $3.5\;d\;S{\cdot}m^{-1}$ respectively. Leaf color, turf quality, coverage rate, and growth rate were checked under the salty condition in reclaimed land for 2 year. Creeping bentgrass cultivars of T-1, Penn links, and Crenshaw presented dark green color and Penn A1, Declaration showed lighter green color. Penn A1, Penn A4 and L-93 exhibited the highest overall turfgrass quality. Average visual coverage was 75.3% after eleven weeks after seeding. Dominant, L-93, and Penn A1 resulted in higher visual coverage compared to the other cultivars. There was no difference in density among cultivars at 1 year after establishment. However, Declaration, Penn A1, T-1, and L-93 showed higher density compared to the other cultivars at 2 years after seeding. Creeping bentgrass showed different quality, density and color in salty soil (ECe: $0.25-3.5\;d\;S{\cdot}m^{-1}$) and from application of salty irrigation water (ECw: $0.28-3.3\;d\;S{\cdot}m^{-1}$) conditions. These results will be useful where selecting green cultivars for the golf courses in reclaimed land area.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.22 no.7
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• pp.492-507
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• 2010

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2009. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) Research trends of thermal and fluid engineering have been surveyed as groups of general thermal and fluid flow, fluid machinery and piping, and new and renewable energy. Various topics were covered in the field of general thermal and fluid flow such as an expander, a capillary tube, the flow of micro-channel water blocks, the friction and anti-wear characteristics of nano oils with mixtures of refrigerant oils, etc. Research issues mainly focused on the design of micro-pumps and fans, the heat resistance reliability of axial smoke exhaust fans, and hood systems in the field of fluid machinery and piping. Studies on ground water sources were executed concerning two well type geothermal heat pumps and multi-heat pumps in the field of new and renewable energy. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics and industrial heat exchangers. Researches on heat transfer characteristics included the heat transfer in thermoelectric cooling systems, refrigerants, evaporators, dryers, desiccant rotors. In the area of industrial heat exchangers, researches on high temperature ceramic heat exchangers, plate heat exchangers, frosting on fins of heat exchangers were performed. (3) In the field of refrigeration, papers were presented on alternative refrigerants, system improvements, and the utilization of various energy sources. Refrigeration systems with alternative refrigerants such as hydrocarbons, mixed refrigerants, and $CO_2$ were studied. Efforts to improve the performance of refrigeration systems were made applying various ideas of suction line heat exchangers, subcooling bypass lines and gas injection systems. Studies on heat pump systems using unutilized energy sources such as river water, underground water, and waste heat were also reported. (4) Research trend in the field of mechanical building facilities has been found to be mainly focused on field applications rather than performance improvements. In the area of cogeneration systems, papers on energy and economic analysis, LCC analysis and cost estimating were reported. Studies on ventilation and heat recovery systems introduced the effect on fire and smoke control, and energy reduction. Papers on district cooling and heating systems dealt with design capacity evaluation, application plan and field application. Also, the maintenance and management of building service equipments were presented for HVAC systems. (5) In the field of architectural environment, various studies were carried to improve indoor air quality and to analyze the heat load characteristics of buildings by energy simulation. These studies helped to understand the physics related to building load characteristics and to improve the quality of architectural environment where human beings reside in.

• Clean Technology
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• v.24 no.2
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• pp.127-134
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• 2018

To reduce the environmental pollution by $NO_x$ from ship engine, International maritime organization (IMO) announced Tier III regulation, which is the emmision regulation of ship's exhaust gas in Emission control area (ECA). Selective catalytic reduction (SCR) process is the most commercial $De-NO_x$ system in order to meet the requirement of Tier III regulation. In generally, commercial ceramic honeycomb SCR catalyst has been installed in SCR reactor inside marine vessel engine. However, the ceramic honeycomb SCR catalyst has some serious issues such as low strength and easy destroution at high velocity of exhaust gas from the marine engine. For these reasons, we design to metallic structured catalyst in order to compensate the defects of the ceramic honeycomb catalyst for applying marine SCR system. Especially, metallic structured catalyst has many advantages such as robustness, compactness, lightness, and high thermal conductivity etc. In this study, in order to support catalyst on metal substrate, coating slurry is prepared by changing binder. we successfully fabricate the metallic structured catalyst with strong adhesion by coating, drying, and calcination process. And we carry out the SCR performance and durability such as sonication and dropping test for the prepared samples. The MFC01 shows above 95% of $NO_x$ conversion and much more robust and more stable compared to the commercial honeycomb catalyst. Based on the evaluation of characterization and performance test, we confirm that the proposed metallic structured catalyst in this study has high efficient and durability. Therefore, we suggest that the metallic structured catalyst may be a good alternative as a new type of SCR catalyst for marine SCR system.

• Tuberculosis and Respiratory Diseases
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• v.45 no.1
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• pp.45-56
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• 1998

Background: Lung cancer continues to increase worldwide. Also, the proportion of female patients incease and adenocarcinoma is the predominant histological type among lung cancer in many western countries. So, we studied these current trends of lung cancer by clinical approach of recent patients from our department Method: We conducted a retrospective analysis on 212 subjects who were diagnosed with lung cancer at the department of chest medicine in National Medical Center between January 1990 and July 1996. The contents of analysis were patient's profile, clinical manifestation, smoking habits, accuracy of diagnostic methods, histological cell type, staging and treatment, etc. Results: The results were as follows. 1) The ratio of male to female was 5.2 : 1. The peak incidence of age was 7th decade(35.4%). 2) Chief complaints were cough, dyspnea and chest pain, etc. The most common duration of symptoms before the first admission was less than 3 months(57.7%). On the other side, duration more than 1 year represented 6.5%. The early diagnosed patients has been increased from the 1980s. 3) Smokers among the total patients were 77.2%. The proportion of smokers in sqamous cell carcinoma, small cell carcinoma and adenocarcinoma were 88.4%, 85.7% and 55.7%, respectively. Smoking history and histological cell type were correlated in squamous and small cell carcinoma. 4) Squamous cell carcinoma is still the predominant histological type (44.8%), but, adenocarcinoma increased more than the previous study(30.7%). The other histological types were small cell carcinoma(17.0%) and large cell carcinoma(3.8%) in order of their proportions. 5) The accuracy of diagnostic methods were as follows: sputum cytology 75.3%, bronchoscopic biopsy 65.7%, lymph node aspiration cytology 95.8%, percutaneous lung aspiration cytology 94.6% and open lung biopsy 100%. The general accuracies of diagnostic methods were improved than previous studies. 6) Performance status scales on admission were relatively good. After diagnosis, chemotherapy and/or radiotherapy were undertaken in 69.3% of the patients, and only 7.5% of the patients were operated. Conclusion: In our study, squamous cell carcinoma is still the predominant histological cell type, but, adenocarcinoma continues to increase. Because adenocarcinoma is less correlated with smoking habits, further evaluation of other carcinogens than smoking is requested. Screening and early diagnosis of lung cancer is important for good performance status scales in spite of advanced stages. But, we think that the prevention, for example, stop smokings is more important as because of no perfect treatment for lung cancer.

• Journal of Korean Home Economics Education Association
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• v.19 no.2
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• pp.61-75
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• 2007

The method used in this descriptive study is the survey. The purpose of the study is to investigate performances of middle school home economics(HE) teachers regarding the HE subject. Respondents in this study were 177 HE teachers. Questionnaires from HE teachers were collected through e-mails. With the operation of the SPSS/Win (ver10.1) program, the analyses such as mean, standard deviation, frequencies, percents, t-test and ANOVA are done to see the relations between the related variables. The results of this study were as follows. First, the middle school HE teachers performed well above the standards in terms of planning, execution, and evaluation about self supervision related to HE. Second, the HE teachers collected materials for instruction by using literary (books) survey, Internet and mass media. They mainly focused on improving ways of "teaching and learning" and deepening the studies related to contents of textbooks. Third, the HE teachers used various ways to improve self supervision in the following order: mass media, literary (books) survey, participation in societies for researches, meetings, various training and field trip More than half of the middle school HE teachers proceeded to graduate schools, joined meetings for researches and had experiences of taking classes in private institutes. They also made a field trip once or twice a year and depended much on TV programs and education broadcasting programs as ways of improving their performances related to self supervision. While they were actively sharing information with their peer group, they made little effort at analyzing and evaluating their classes and utilizing expert group for their classes. The main problems as to self supervision were that only the half of the HE teachers responded that they were performing self supervision related to their classes well above the standards and the area where they heavily focused on has been "teaching and learning" and "the studies related to contents of textbooks". Therefore, to motivate incentives of the HE teachers for self supervision, meetings for researches should be activated and various training programs should be developed. In addition, government should give administrative and institutional support through a publication of books introducing detailed ways of self supervision and an establishment of centers and institutions for supporting self supervision.

• Journal of Korea Port Economic Association
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• v.26 no.4
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• pp.188-206
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• 2010

Data Envelopment Analysis(DEA) is an operations research-based method for measuring the performance efficiency of decision units that are characterized by multiple inputs and outputs. DEA has been applied successfully as a performance evaluation tool in many fields. However, it has not been extensively applied in the shipbuilding industry. This paper applied the input-oriented DEA model, and Malmquist indices to the 7 shipbuilding firms to measure the efficiency and productivity changes during the period of 2004 to 2009. The Malmquist indices will be decomposed into three components such as pure efficiency change, scale efficiency change, and technical change. The empirical results show the following findings. First, the DEA findings indicate that main source of inefficiency is scale rather than pure technical. Second, the Malmquist indices show that an overall decrease in productivity.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.441-450
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• 2011

This study examined the effects of feeding whole-crop barley silage (BS), corn silage (CS) and the mixture of BS and CS (CB) on feed consumption, daily gain, nutrients apparent digestibilities and blood parameters in order to investigate the feed evaluation in Korean black goats. BS, CS, and CB were fed to twelve Korean black goats, which were allocated into three groups in metabolic cages according to the latin-square design. As a result, dry and organic matter intakes for goats per day have shown a tendency to decrease in the order of CS, CB and BS, but there were no significant differences. We also found a similar tendency when the intakes of crude protein, crude fat, and non-fiber carbohydrates (NFC) were examined. However, ADF and NDF consumptions showed a decreasing tendency in the order of CB, BS and CS. Dry matter intakes per metabolic body weight showed the decreasing tendency in the order of CS (57.6g), CB (53.8g) and BS (52.7g), however with no statistical differences. Average daily gain of 64.2 g in CB was significantly higher than the other groups (42.0g to 46.0g). Nitrogen intakes and nitrogen retention showed a decreasing tendency in the order of CS, CB and BC. Nevertheless, nitrogen retention in CS group was higher by 30% than that of the BC group with p<0.05. Apparant digestibilities of dry and organic matters were 72.6 and 72.8% for the CS group respectively, which were significantly higher than those of the BS group (67.5 and 69.0%) and the CB group (66.0 and 67.1%). In conclusion, the results of this study demonstrated that the CS group showed more positive feed consumption, digestibility, and nitrogen retention in Korean black goats than those of BS group. The CB group, however, showed similar results to the results of the CS group.

• Clinics in Shoulder and Elbow
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• v.12 no.1
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• pp.53-60
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• 2009

Purpose: Primary osteoarthritis on the elbow is the result of the growth of osteophytes and contracture of the capsule. It often causes disability on joint motion and pain while exercising. As arthroscopy has developed, the arthroscopic diagnosis and treatment of the elbow have recently become more generalized as well. Therefore, we like to report on arthroscopy for treating elbow arthritis and its results. Materials and Methods: This study includes 23 cases of elbow arthritis that were seen between 2005 June to 2007 June and these patients didn't response to conservative treatment. From this we excluded 18 cases that underwent arthroscopic surgery and among these 18 cases, 6 cases underwent ulnar nerve transfer. The average observation time was 21.3 months and the average age was 48.4 years (range: 22-66 years). The pre and post operative pain was evaluated with using the Visual Analogue Scale (VAS) and functional evaluation was done with using the Mayo elbow Performance Score (MEPS) with the range of joint motion. Results: The VAS score at the last follow up was significantly decreased from 3.4 to 1.9 compare to the preoperative score. The range of joint motion was improved by 25 (0-40) to 8.5 (0-20) in extension and 101.7 (80-140) to 125.2 (85-140) in flexion (p<0.05). The MEPS always showed significant improvement by showing an increase from 65.4 (40-85) to 87.9 (55-100). However, 3 cases showed a decreased range of motion after the operation. One case showed ulnar nerve symptoms after surgery. Conclusion: An arthroscopic procedure can treat the pathologic processes associated with arthritis of the elbow and it was safe and effective in this series.

• Analytical Science and Technology
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• v.17 no.6
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• pp.496-513
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• 2004

This study was carried out to evaluate the performance of sampling and analytical methodology used for the measurement of toxic volatile organic compounds (VOCs) in the ambient air. VOCs were determined by the adsorbent tube sampling and automatic thermal desorption coupled with GC/MSD analysis. Target analytes were 33 compounds including major aromatic compounds such as BTEX, and halogenated compounds. The methodology was investigated with a wide range of different adsorbents which are commercially available and have been frequently adopted for the VOC measurement. A total of 10 adsorbents were tested in this study: 6 carbon-based adsorbents such as Carbotrap, Carbopack B, Carbosieve S-III, Carboxen 1000, Carbotrap C, Activated Charcoal; and 4 polymer-based adsorbents including Tenax, Porapak Q, Chromosorb 102, and Chromosorb 106. The sampling performance was evaluated with respect to the sampling capacity of VOCs with single-adsorbent and multiple-adsorbents methods for standard samples and field samples. As a result, the best adsorbents for single-adsorbent method in the sampling of toxic organic compounds (including benzene, toluene, xylenes etc.) appeared to be Carbotrap, Carbopack B and Tenax TA. On the other hand, Chromosorb 102, Chromosorb 106 and Porapak Q were found to be unsuitable adsorbents for VOC measurement based on thermal desorption method. Multi-adsorbent packings were evaluated with 4 carbon-based adsorbents, which classified by 3 combination sets of double adsorbents and 2 combination sets of triple adsorbents. The results indicated that the most suitable combination for toixc VOC measurements is Carbotrap C with Carbotrap. Multi-sorbents tubes packed with a strong adsorbent such as Carbosieve S-III or Carboxen 1000 were found to be relatively unsuitable for several compounds, not only owing to the effect of migration of adsorbed compounds from weaker adsorbent to stronger adsorbent, but to hydrophobic nature of the adsorbents. Therefore, it should be addressed that selection of a proper adsorbent (or combination of multi sorbents) is extremely important to obtain reliable data for the concentrations of toxic VOCs in indoor and outdoor environments.

• Journal of Korea Technology Innovation Society
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• v.12 no.4
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• pp.788-818
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• 2009

Renewable energy refers to solar energy, biomass energy, hydrogen energy, wind power, fuel cell, coal liquefaction and vaporization, marine energy, waste energy, and liquidity fuel made out of byproduct of geothermal heat, hydrogen and coal; it excludes energy based on coal, oil, nuclear energy and natural gas. Developed countries have recognized the importance of these energies and thus have set the mid to long term plans to develop and commercialize the technology and supported them with drastic political and financial measures. Considering the growing recognition to the field, it is necessary to analysis up-to-now achievement of the government's related projects, in the standards of type of renewable energy, management of sectional goals, and its commercialization. Korean government is chiefly following suit the USA and British policies of developing and distributing renewable energy. However, unlike Japan which is in the lead role in solar rays industry, it still lacks in state-directed support, participation of enterprises and social recognition. The research regarding renewable energy has mainly examinedthe state of supply of each technology and suitability of specific region for applying the technology. The evaluation shows that the research has been focused on supply and demand of renewable as well as general energy and solution for the enhancement of supply capacity in certain area. However, in-depth study for commercialization and the increase of capacity in industry followed by development of the technology is still inadequate. 'Cost-benefit model for each energy source' is used in analysis of technology development of renewable energy and quantitative and macro economical effects of its commercialization in order to foresee following expand in related industries and increase in added value. First, Investment on the renewable energy technology development is in direct proportion both to the product and growth, but product shows slightly higher index under the same amount of R&D investment than growth. It indicates that advance in technology greatly influences the final product, the energy growth. Moreover, while R&D investment on renewable energy product as well as the government funds included in the investment have proportionate influence on the renewable energy growth, private investment in the total amount invested has reciprocal influence. This statistic shows that research and development is mainly driven by government funds rather than private investment. Finally, while R&D investment on renewable energy growth affects proportionately, government funds and private investment shows no direct relations, which indicates that the effects of research and development on renewable energy do not affect government funds or private investment. All of the results signify that although it is important to have government policy in technology development and commercialization, private investment and active participation of enterprises are the key to the success in the industry.