• 전자공학회논문지 IE
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• v.48 no.3
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• pp.16-19
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• 2011

Differentiated Service is an IP QoS ensuring method based on packet marking that allows packets to be prioritized according to user requirements. During the time of congestion, more low priority packets are dropped than high priority packets. Different policy models are used to determine how to mark the packet. This paper investigated the performance of Differentiated Service using time sliding window with 3 color marking (TSW3CM). Simulation results using NS-2 showed that Differentiated Service can provide the quality of service requirements.

• Korean Journal of Veterinary Service
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• v.17 no.3
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• pp.198-207
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• 1994

4, 919 Samples of the slaughtered cattle(female) were investigated the abattoir in southern Kangwon to reveal the incidence rates of abdominal fat necrosis from June to December 1993. The results obtained were summarized as follows ; 1. The incidence rate of abdominal fat necrosis investigated from 4, 919 samples was 4.39%. 2. It revealed that the incidence rate of abdominal fat necrosis increased gradually with the advance in the age, 2.5% in below 5 years, 6.0% in 6 years, 7.2% in 7 years, 8.5% in 7 years, 8.9% in older than 9 years and that incidence rate of the sites of lesion, pericolonic fat 84.7%, perirectumic fat 48.6%, perirenal fat 37.9%. mesenteric fat 24.0%, others 7.8%. 3. The size of necrotic fat were $2{\times}3cm{\sim}10{\sim}18{\times}15{\sim}25cm$ in average and color was yellowish white or milk white.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.1
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• pp.40-49
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• 2003

Dynamic characteristics of water hammer arresters installed in a building water supply system have been investigated numerically by utilizing a commercial code that employs the method of characteristics. Some preliminary results with those arrester models produced in this study agree well with the previously reported. Then, the arrester models have been incorporated into a water supply pipe system of a 59 $m^2$apartment unit constructed by a leading construction company, and their dynamic characteristics have been investigated, especially on the reduction in the water hammer pressure. It is found that the setting of the arresters in the pipe system, which is recommended by the company, may not be proper for reducing the pressure down below 1,082.0 kPa (10.0 kg$g_f$/$cm^2$) when quick-closure valves in the pipe system are closed within 30 ms at the static pressure of 542.6 kPa (4.5 kg$g_f$/$cm^2$). More arresters in the system may be required to meet pressure criteria stated on the related standards and codes.

• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.100-110
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• 2010

The main roots of CM service contracts include existing customer repurchases and those made by new customers by existing ones. The study on customers and loyalty can be factors to strengthen CM's competitiveness. However, there have been little attempt to study customer satisfaction and customer loyalty. Construction Management (CM), the advanced construction management method, was introduced 15 years ago in the mid 1990's in the domestic market. The aim of this research is to build a model that can predict customer loyalty based on how much customers are satisfied with CM service. To measure customer satisfaction and loyalty, this research surveyed 135 decision-makers who have experienced CM services. Customer satisfaction was tested and analyzed according to different phases: planning, designing, procurement, construction, and post construction. Referral intention was tested based on NPS theory. Customer types were divided into detractors, passively satisfied and promoters according to the tested measurement and multinomial logistic regression between the satisfaction by construction phases and customer types. This research resulted to a model that can predict customer types: detractors, passively satisfied and promoters, which were determined according to satisfaction level. The initial planning phase also revealed which factor is most influential for a customer to become promoter. These results can be used to acquire customer loyalty by managing the satisfaction of customers through a project under an Internet-based environment. Such can provide the needed information in quickly exploring positive and negative word-of-mouth feedbacks.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.1
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• pp.31-40
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• 2006

This paper describes the results of a series of field experiments which are carried out to assess the reduction effect of railroad vibration by utilizing waste tires. The ground vibration due to train service is measured in Honam Railroad line and Kyongbu Railroad line to assess the ground vibration with the domestic railroad line and train type before field model test. From the results of these tests, frequency on train service is presented from 5Hz to 100Hz and a range of excellence frequency is presented to be about from 20Hz to 40Hz in the domestic railroad line. Also, plate bearing tests are conducted to evaluate the variation of bearing capacity with different thickness of the waste tire layer and the fill layer. Finally, field model test is performed by using tire chips ($5cm{\times}5cm$ in size) as a reduction material of railroad vibration. The reduction effect of railroad vibration by utilizing waste tires increases with increasing the thickness of the waste tire layer and the frequency of the vibration source. The results of this experimental study was shown that the waste tire can be used for reduction of the railroad vibration.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.649-652
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• 2015

Previous marking policy for the AF service of TCP traffic in the Diffserv network have no sufficient consideration on the effect of RTT and target rate. In this paper, in order to improve fairness Index by the effect RTT difference of TCP traffic, we propose the modified TSW3CDM(Time Sliding Window Three Color Dynamic Marker) based on average transfer rate estimation and the flow state. The proposed algorithm is dynamic marking policy that do allocate band width in proportion to transmission rate. To evaluate the performance of the proposed algorithm, We accomplished a computer simulation using NS-2. From simulation results, the proposed TSW3CDM algorithm improves fairness index by comparison with TSW3CM.

• The Plant Pathology Journal
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• v.20 no.2
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• pp.92-96
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• 2004

Environmental factors such as soil moisture, land management, and weather conditions affecting Fusarium wilt of sweet potato were investigated in major sweet potato cultivation regions in Korea. Fusarium wilt occurred mainly in reclaimed terracing lands, which are flattened and located in hilly to mountainous areas at the base of the mountain, in early seasonal cultivation regions. Disease severity was lower in reclaimed fields with natural slope. The development of Fusarium wilt in the fields was highly correlated with precipitation during planting period (r=-0.96**). Fusarium wilt was more severe in fields with less than 20 cm of available soil depth than in fields with over 20 cm of available soil depth. Greenhouse studies were consistent with field studies that less soil moisture content caused severe Fusarium wilt of sweet potato. These results indicate that low rainfall and moisture of soil with low effective soil depth during planting period are important environmental factors influencing the development of Fusarium wilt.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2020.06a
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• pp.48-49
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• 2020

Recently the diversification of construction market and the continuous reduction of construction amount are raising the need of alternative delivery method in the construction industry. The foreign advanced companies actively adopted the CM at Risk delivery method where they perform the service of agent CM in the design phase, and agree GMP(Guaranteed Maximum Price) with the client at the time of 50~80% completion of design. Even in Korea they began to apply that method to pilot projects. In CM at Risk, through the early participation of builder, the level of design completion can be improved and the change order and construction period delay can be minimized. On the other hand, GMP is usually calculated when the design is about 80% complete, so there is uncertainty in the construction cost. Therefore, in this research, the increased amounts of construction cost are analyzed in a number of public construction projects, and GMP calculation process is proposed using the analysis results and CBR(Case-Based Reasoning) technique to reduce the construction cost increase in the construction phase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.216-220
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• 2002

The microbiological examinations of food service operations were conducted for the hygienic evaluation at four elementary schools in Busan, Korea. Total one hundred and seventy two swabbed samples using sponge were collected from the surface of environments, utensils and equipments of food service facilities and analyzed by measuring the total, coliform and psychrotrophic count. Sampling sites were the surfaces of floors, drains, walls, knives, cutting boards, rubber gloves, vinyl aprons, plastic containers, carriers, shelves, trays, dry shelves, electric tray dryer, food containers, soup containers, rice cookers, frying pans, boiling cookers, refrigerators, dumb waiters and dishwashers. The swabbed samples kept in an ice-parked box were transported to a laboratory and analyzed. The results demonstrated that the degree of contamination depended on the sampling sites. Averages of total counts of surface swab samples were ranged from 0.62 to 7.79 Log CFU/200 cm$^2$. The level of coliforms were ranged from not detectable to 5.26 Log CFU/200 cm$^2$, and those of psychrotrophs from not detectable to 6.15 Log CFU/200 cm$^2$. The severely contaminated sites were dumb waiters, drains, rice cookers, knives, plastic containers and floors. Also cutting boards, rubber gloves, carriers, drying shelves, vinyl aprons, boiling cookers, soup containers, frying pans and refrigerators were highly contaminated with the level of abode 3.5 Log CFU/200 cm$^2$. Therefore, those sites should be focused and controlled according to control points of sanitation standard operating procedures (SSOP). Also, periodic microbiological examination in addition to visual examination is recommended on these highly contaminated sites indicated above results at food service operations in elementary school.

• Journal of Bio-Environment Control
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• v.15 no.1
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• pp.107-113
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• 2006

These studies were carried out to investigate the quality of green tea processed by different pan-firing hand rolling and to select the best conditions during the procedure of green tea processing the results were as follows. At harvestion tea plant leaf, tea plants had 4 leaves. each leaf size was 7.5 cm'$\square$2.6 cm, and weight of 100 buds 46.6 g. The increase of pan-fired time decreased in the moisture content and yield of green tea. After processing green tea, 5 times pan-fired one had much more contents of total nitrogen (T-N:5.31%), caffeine (2.00%) and total amino acid (T.A.A. : 3,046 mg%) and less content of tannin (13.41%) than the other treatments. but 3 times pan-fired one had the highest contents of vitamin C (204.3 mg%) and chlorophyll (365.0 mg%) among three kinds pan-firing method. Sixteen kinds of free amino acid including theanine as a good taste component of pan-fired green tea were isolated and measured by HPLC. Free amino acid (FAA) contents were in the range of $2,683{\sim}2,925$ mg% and among various pan-firing methods, 5 tims pan-fired one had the highest content of F.A.A. Among these free amino acids, theanine occupied as much as $56.4{\sim}61.3%$ of F.A.A. Lightness, yellowness and redness of 5 times pan-fired green tea were middle value among three different treatments. Besides, it gained the highest score of sensory evaluation among them. These above results suggested that 5 times pan-fired green tea was considered to be the best level as pan-firing times of green tea processing.