• New & Renewable Energy
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• v.7 no.3
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• pp.83-91
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• 2011

The purpose of this study is to select appropriate location factors for wind power plant, provide detailed classification criteria, and find out appropriate sites for installing wind power plant in Gangwondo. In this study, the following 11 factors were extracted for site selection of wind power plant : wind resource, topography (valley angle, distance to the ridge), forest density, land use, preservation area, national park, Baekdu-Daegan, noise, shade, Transmission Line, and approaching roads. Each factor had relatively different level of importance so that AHP (Analytic Hierarchy Process) technique was used to calculated the weighted value per factor. For overlay analysis, classification criteria were prepared for each factor and each factor was classified into 3 grades : very appropriate, intermediate, poor. According to overlay analysis, the areas which received the highest grade (grade 5) was only in 0.16% of the total area of Gangwondo and had a tendency to exist along the mountain ridge over 600-meter elevation. Through analyzing the yearly average of wind power density, it was proved that the wind power density of areas with grade 4 or 5 had abundant wind resource over $400W/m^2$.

• Journal of the korean academy of Pediatric Dentistry
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• v.21 no.2
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• pp.429-438
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• 1994

Since the introduction of pit and fissure sealants in the early 1970's, many studies have been published amply documenting the efficacy of these materials as caries-preventive agents. However, the acceptance of the technique by dentist has been questionable. This survey was investigated the attitudes toward and use of pit and fissure sealants by dentist in Chonbuk area. The results were as follows: 1. Utilization of pit and fissure sealants is very high. Only 15% of dentists never use pit and fissure sealants, whereas 85% generally use pit and fissure sealants. 2. Most dentists reported that their knowledge of pit and fissure sealants was gained through dental schools education. 3. Concern about difficult to sell' to patient, poor retention of pit and fissure sealants and unsubstantiated by research were given as the main reasons why pit and fissure sealants was not used. 4. Patient demands and various educate program were given as important factors that would lead to increase use of pit and fissure sealants.

• IE interfaces
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• v.23 no.2
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• pp.108-117
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• 2010

Wireless sensor network may be installed where it is hard to access or where one has to constantly gather data without any human's monitoring. Sensors which compose a sensor network are usually small with poor battery capacities and thus energy-efficient usage is very important because of difficulties in replacing or recharging the batteries to make the lifetime of the whole sensor network longer. LEACH protocol, a well-known hierarchical routing protocol, may resolve this problem by distributing the role of cluster header evenly to the sensor nodes in the whole area of network at each round. In this thesis, we introduce a variant of LEACH protocol which considers the distance between base station and sensors in the way that if a node is far from the base station then the probability that this node becomes a cluster header is low. Experiments to evaluate the energy efficiency and the ability to collect the information show that the proposed method in this paper has maintained much wider sensing area while keeping the energy efficiency same as LEACH.

• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.2
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• pp.87-94
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• 2007

It has been argued that the use of plastics can cause problems during design and manufacture owing to their low strength, relatively poor thermal conductivity and large thermal expansion. However, the advantages of plastics e.g., corrosion resistance, low cost, curtailment of weight, design flexibility etc., can compensate abundantly for the disadvantages. This study analyzes and compares the heat transfer performance characteristics of automotive compact oil cooler composed of plastic tube bundle with conventional metal oil cooler on the same core area basis as diameter, tube thickness, number of tube or tube arrangement varies. The performance analyses are accomplished by use of computational fluid dynamics program Fluent 6.2, which is verified and compared with the results of performance tests. The result of analyses is coincided with that of experiments. Flow pattern at air side according to tube arrangement is dominant factor which affects heat dissipation in case of similar total heat transfer surface area.

• Journal of Nutrition and Health
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• v.33 no.4
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• pp.454-463
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• 2000

The purpose of this study was to assess the biochemical nutritional status of the long-lived elderly. The subjects of the study were 148 elderly people of age over 85 years living in Kyungpook Sung-Ju area who have no problem in daily living. The anthropometric measurement and biochemical assessment of the blood sample were carried out. The subject group for this study was composed of 25.9% males and 74.1% females, the average age being 87 years old. The mean Body Mass Index(BMI) of the male and female subjects were 20.7 and 21.2 respectively. The average body fat amounts of the male and female were 21.4% and 29.8% respectively, and the average waist/hip ratios were 0.9 and 0.7 respectively. The mean levels of the total blood protein and albumin of the subjects were in the normal ranges. The mean levels of serum cholesterol and triglyceride were 167.9mg /dL and 123.9mg/dL respectively. The mean levels of the subjects below normal range of hemoglobin were 63.5%. Serum levels of antioxidant nutrients were very poor. The mean levels of serum lipid peroxidation products were 3.3nmol/mL. BMI and WHR were positively correlated with the serum cholesterol levels. The resuts showed that the long-lived elderly had good nutritional status except for antioxidant nutrients status. In addition antioxidant supplement for long-lived elderly may be effective to maintain healthy life in later years.

• Weed & Turfgrass Science
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• v.6 no.1
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• pp.55-60
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• 2017

Shade affects turf quality by reducing light for photosynthesis. The shade tolerance of the tropical grasses, Digitaria longiflora and Axonopus compressus were evaluated against Stenotaphrum secundatum (St. Augustinegrass). The grasses were established under shade structures that provide 0%, 50%, 75% or 90% shade level for 30 days. A suite of leaf traits, recorded from similar leaf developmental stage, displayed distinct responses to shade conditions. Leaf length, relative to control, increased in all three species as shade level increased. The mean leaf extension rate was lowest in St. Augustinegrass (80.42%) followed by A. compressus (84.62%) and D. longiflora (90.78%). The higher leaf extension rate in D. longiflora implied its poor shade tolerance. Specific leaf area (SLA) increased in all species with highest mean SLA increase in D. longiflora ($348.55cm^2mg^{-1}$)followed by A. compressus ($286.88cm^2mg^{-1}$) and St. Augustinegrass ($276.28cm^2mg^{-1}$). The highest SLA increase in D. longiflora suggested its lowest performance under shade. The percent green cover, as estimated by digital image analysis, was lowest in D. longiflora (53%) under 90% shade level compared to both species. The relative shade tolerance of the three turfgrasses could be ranked as St. Augustinegrass > A. compressus > D. longiflora.

• Journal of the East Asian Society of Dietary Life
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• v.13 no.5
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• pp.362-370
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• 2003

This study was conducted to investigate the dietary behavior and utilization of university foodservice in Incheon area. Self administered questionnaires were collected from 305 students. Statistical data analysis was completed using a SPSS v. 10.0 program. The results are summarized as follows: Most students had poor dietary behavior, such as skipping meals. Only 21.4% of male students and 30% of female students responded to have breakfast regularly. About 60% of students were utilizing for lunch at the university foodservice and 3.9% of them for dinner, which mainly caused by the reasons “low price”, “time saving”, “near place”. In particular, only 21% of students used the university foodservice daily. More than 80% of students responded to have lunch at restaurants around campus when they did not have meals at the university foodservice. Reasons for not utilizing the university foodservice were responed as simple menus and tasteless, etc. Recommendations for the improvements of the university foodservice can be summarized as menu variation, emphasis on taste, reducing of noise, expending opening time, reducing waiting time, sanitation, change of old utensils and comfortable atmosphere of dining hall.

• Corrosion Science and Technology
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• v.6 no.3
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• pp.83-89
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• 2007

It is expected that advanced high strength steels (AHSS) would be widely used for vehicles with better performance in automotive industries. One of distinctive features of AHSS is the high value of carbon equivalent (Ceq), which results in the different properties in formability, weldability and paintability from those of common grade of steel sheets. There is an exponential relation between Ceq and electric resistance, which seems also to have correlation with the thickness of electric deposition (ED) coat. Higher value of Ceq of AHSS lower the thickness of ED coat of AHSS. Some elements of AHSS such as silicon, if it is concentrated on the surface, affect negatively the formation of phosphates. In this case, silicon itself doesn't affect the phosphate, but its oxide does. This phenomenon is shown dramatically in the welding area. Arc welding or laser welding melts the base material. In the process of cooling of AHSS melt, the oxides of Si and Mn are easily concentrated on the surface of boundary between welded and non‐welded area because Si and Mn could be oxidized easier than Fe. More oxide on surface results in poor phosphating and ED coating. This is more distinctive in AHSS than in mild steel. General results on paintability of AHSS would be reported, being compared to those of mild steel.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.652-661
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• 2006

The cut slopes in Jinju area constitute the Cretaceous Sedimentary rock which is one of the most poor ground conditions. The geological rocks of the cut slopes are correlated with Jinju Formation. Most of the rocks consist of Black Shale layer, but the lower parts consist of Alkorsic White Sandstone. So, It is characteristic of the differential weathering due to the difference of rock species. Moreover, vertical joints which concentrate on the released rock and weak rock fragments are accompanied with minor faults. We make out face mapping about each slopes through the detailed field-study and deduce RMR and SMR from the field data. The strength properties of rocks were obtained from references, indoor tests, and Back Analysis method. And, choosing properties were used in the stability analysis as stereographic projection and limit equilibrium analysis and we establish the countermeasures for the cut slopes.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.418-437
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• 1995

The effect of the hydroxyapatite coatings on Titanium implants has been the subject of recent investigations. So far, the use of HA coating remains substantially controversial.This study was aimed to evaluate histologically the bone healing patterns around titanium plasm sprayed(TPS) amd HA-coated implant after implantation into the femur neck of ten adult dogs. After implantation, animals were sacrificed at the intervals of 2,4,6,8 and 12 weeks.The fluorescent dyes were injected on the postoperative 4th and 12th week into the animals supposed to be killed at the 12th week. The morphology and direction of new bone formation was similar in both TPS and HA-coated implants.There was a tendency toward more bone formation in the cortical bone area than in the cancellous bone area. Histologically,in the interface of the HA-coated implants, bone response and bone maturation was faster, compared to the TPS implants in the 2nd and 4th week. By fluorescent microscopy, new bone formation was active in the 4th week around both implants and was directed from the periosteum overlying cortical bone to the cancellous bone. These results suggest that the bone formation and maturation is faster during the early healing stage in the interface of the HA-coated implant and where the cortical bone quality is poor, HA coated implant is superior to the TPS implant in the early phase of new bone formation.