• The Journal of Korean Institute of Communications and Information Sciences
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• v.38B no.3
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• pp.207-215
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• 2013

This paper is channel assignment and scheduling techniques for efficient wireless AMI network. In AMI system, the multi-channel cluster network to be proposed defines the communication channel between NC (Network Coordinator) and CDA (Clustered Data Aggregator) as the network channel. CDA and OMD(Out Meter display) and communication channel between SMD(Smart Meter Device) are defined as the group channel. AMI network of the multi-channel cluster based in which the network channel and group channel is mixed increases the administration efficiency through the physical/logical consumer channel clustering. The reliability of inspection data through the channel use distinguished between the adjacent cluster is enhanced. In addition, the fast aggregation of data is possible and the size of a metering network is increased through the channel allocation of the multichannel cluster based.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.2
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• pp.209-216
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• 1997

A feature is well known as a medium to integrate CAD, CAPP and CAM systems. For a part drawing including both simple geometry and compound geometry, a process plan such as the selection of process, machine tool, cutting tool etc. normally needs simple geometry data and non-geometry data of the feature as the input. However, a extended process plan such as the generation of process sequence, operation sequence, jig & fixture, NC program etc. necessarily needs the compound geometry data as well as the simple geometry data and non-geometry data. In this paper, we propose a feature data model according to the result of analyzing necessary data, including the compound geometry data, the simple geometry data and the non-geometry data. Also, an example of the feature data model in milling process planning is described.

• Journal of Dental Rehabilitation and Applied Science
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• v.33 no.4
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• pp.260-268
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• 2017

Purpose: Manufacturing with AM (Additive manufacturing) technique has many advantages; but, due to insufficient study in the area, it is not being widely used in the general clinic. In this study, differences of flexural strength among various materials of 3 unit fixed dental prosthesis were analyzed. Materials and Methods: A metal jig for specimens that had a 3-unit-fixed dental prosthesis figure were fabricated. The jigs were made appropriately to the specifications of the specimens. Three different kinds of materials of specimens which were NC (mathacrylic esther based), DP-1 (Bisphenol A epoxy acrylate type oligomer based), and DT-1 (urethane acrylate based) were printed with DLP machine. Five specimens for each kind of material were printed with an angle of $30^{\circ}$ from the horizontal surface. The specimens were placed on the jig and the flexural strength was measured and recorded using Universal testing machine. The recorded data was analyzed in SPSS using One-way ANOVA and Tukey HSD to determine the significance of the differences of flexural strength among the groups. Results: The flexural strengths of each group were the followings: NC, $1119{\pm}305$ N; DP-1, $619{\pm}150$ N; DT-1, $413{\pm}65N$. Using One-way ANOVA and Tukey Honestly Significant Difference test, significant difference was found between NC and the other groups (P < 0.05), but there was no significant difference between DP-1 and DT-1 (P > 0.05). Conclusion: Higher flexural strength was shown in 3-unit-fixed dental prosthesis that were 3D printed using a DLP machine with NC material.

• Journal of Nutrition and Health
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• v.48 no.2
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• pp.123-132
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• 2015

Purpose: The objective of this study was to examine whether Hamcho freeze-dried powder and Hamcho freeze-dried nano powder have an anti-obese effect on high fat diet-induced obese rats. Methods: Sprague Dawley rats were divided into 6 different groups, each of which was bred for 8 weeks with a different experimental diet: normal diet group (NC), high fat diet group (HFC), high fat diet + 2% Salicornia herbacea L. freeze-dried powder group (2% HS), high fat diet + 5% Salicornia herbacea L. freeze-dried powder group (5%HS), high fat diet + 1% Salicornia herbacea L. freeze-dried nano powder group (1% HSN), high fat diet + 2% Salicornia herbacea L. freeze-dried nano powder group (2% HSN). Results: The 5% HS group showed a weight loss effect in body weight, liver and adipose tissue by reducing the amount of dietary intake and food efficiency ratio. In addition, the 5% HS group showed a significant reduction of serum leptin concentration, while having a beneficial effect on the improvement of lipid metabolism such as increase the serum concentration of adiponectin. However, Hamcho freeze-dried nano powder did not show a weight loss effect. Conclusion: Overall data indicated that Hamcho seemed to have anti-obesity effects. In particular, consumption of 5% Hamcho freeze-dried powder might have beneficial effects on body weight, serum adiponectin level, and lipid profiles since it led to reduced body weight and growth of adipose tissues by suppressing dietary intakes. However conduct of further research studies is needed for analysis of active components and biochemical action mechanism of Hamcho.

• 대한공업교육학회지
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• v.33 no.2
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• pp.259-272
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• 2008

In order to improve the productivity and quality of boat's mold in leisure boat industry, the development of modelling and machining technology of leisure boat's plug is strongly required. The traditional lines drawing approach by hand required the designer to both create fair curves and to make sure that the curves matched up to each other in the three main drawing views: profile, plan, and section. However, one will find when studying lines drawings in books that the curves might look smooth and fair, but the lines do not agree exactly in the three views. Therefore, the 2 dimensional drawing data of leisure boat are transformed using 3 dimensional design s/w and CAM s/w. In addition, the leisure boat is designed with a 3 dimensional s/w. The NC cutting data are generated by the CAM s/w. The surface characteristics of machined surface are investigated at various cutting conditions such as spindle speed, feed speed, and cutting material.

• Nuclear Engineering and Technology
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• v.52 no.9
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• pp.1955-1962
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• 2020

In a sudden shutdown of primary pump or coolant loss accident in a marine nuclear power plant, the primary flow decreases rapidly in a transition process from forced circulation (FC) to natural circulation (NC), and the lower flow enters the steam generator (SG) causing reverse flow in the U-tube. This can significantly compromise the safety of nuclear power plants. Based on the marine natural circulation steam generator (NCSG), an experimental loop is constructed to study the characteristics of reverse flow under middle-temperature and middle-pressure conditions. The transition from FC to NC is simulated experimentally, and the characteristics of SG reverse flow are studied. On this basis, the experimental loop is numerically modeled using RELAP5/MOD3.3 code for system analysis, and the accuracy of the model is verified according to the experimental data. The influence of the flow variation rate on the reverse flow phenomenon and flow distribution is investigated. The experimental and numerical results show that in comparison with the case of adjusting the mass flow discontinuously, the number of reverse flow tubes increases significantly during the transition from FC to NC, and the reverse flow has a more severe impact on the operating characteristics of the SG. With the increase of flow variation rate, the reverse flow is less likely to occur. The mass flow in the reverse flow U-tubes increases at first and then decreases. When the system is approximately stable, the reverse flow is slightly lower than obverse flow in the same U-tube, while the flow in the obverse flow U-tube increases.

• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.796-806
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• 2010

Atopic dermatitis induced NC/Nga mice were used to investigate the efficacy of BDH(Baedokhwan) on the recovery of dermatitic symptoms through its influence on the immune related factors and histological changes. First of all, BDH treated group showed improvement of atopic dermatitis with naked eye observation, and significant decrease of clinical index(CI) was observed after 14 weeks. And Infiltration of leukocytes was suppressed in BDH treated group, and the thickness of hypertrophied epidermis and dermis were decreased. In dorsal skin, BDH treated group showed significant decrease of the ratio of CD3+, CD11b+/Gr-1+ immune cells by 52.8%, 25.2, respectively. And also significant decrease the level of IL-5 mRNA and IL-13 mRNA by 44.4%, 28.0, respectively. In PBMC and serum, BDH treated group showed an decrease of CD4+/CD45+, B220+/CD23+, CD4+, CD8+, CD4+/CD25+ immune cells by 35.0%, 12.6%, 42.7%, 31.6% and 55.6%, respectively, and the level of histamine was decreased by 39.0%. The results above indicated that BDH clinically used for atopic dermatitis treatment has objective validity, and therefore can be provided as the basic data for anti-allergic and anti-inflammatory studies.

• Journal of the Korea Computer Industry Society
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• v.6 no.3
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• pp.539-550
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• 2005

The spanning tree, which is being used the most widely in indoor wiring network, is chosen for the network topology of the optimal LAN design. To apply a spanning tree to GA, the concept of $Pr\ddot{u}fer$ numbers is used. $Pr\ddot{u}fer$ numbers can express he spanning tree in an efficient and brief way, and also can properly represent the characteristics of spanning trees. This paper uses Pareto Stratum-Niche Cubicle(PS-NC) GA by complementing the defect of the same priority allowance in non-dominated solutions of pareto genetic algorithm(PGA). By applying the PS-NC GA to the LAN design areas, the optimal LAN topology design in terms of minimizing both message delay time and connection-cost could be accomplished in a relatively short time. Numerical analysis has been done for a hypothetical data set. The results show that the proposed algorithm could provide better or good solutions for the multi-objective LAN design problem in a fairly short time.

• Journal of Rhinology
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• v.25 no.2
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• pp.80-85
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• 2018

Background and Objectives: Obesity is one of the most important risk factors for obstructive sleep apnea (OSA). There is limited evidence regarding the obesity-related anthropometric characteristics of Korean patients. Materials and Method: Medical records of 984 patients referred to 3 tertiary referral hospitals for habitual snoring or sleep apnea were analyzed. We defined OSA as apnea-hypopnea index (AHI) ${\geq}5$ and analyzed data to determine the anthropometric characteristics of patients with OSA such as neck circumference (NC), waist circumference (WC), hip circumference (HC), and waist to hip ratio (WHR). Results: A total of 952 patients (719 men) were included in the analysis. The main findings were: 1) BMI, WC, NC, HC, and WHR were greater among patients with OSA than among controls (AHI <5); 2) for both sexes, the proportion of patients with an OSA diagnosis increased with age; it increased steeply for women aged >50 years; 3) WC and WHR were most strongly correlated with AHI for men and women, respectively. Conclusion: OSA is associated with anthropometric characteristics, although different patterns were observed between men and women. OSA was more strongly associated with NC or WC among men and with WHR among women.

• Journal of Environmental Science International
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• v.31 no.3
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• pp.265-274
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• 2022

Lipoxygenase is an enzyme, mainly produced by plants, capable of converting unsaturated fatty acids to fatty acids. It has vast application potential in the food, pharmaceutical and agricultural industries. The aim of this study was to isolate novel lipoxygenase-producing bacteria from the environment and to investigate the lipoxygenase enzymatic properties for industrial production. The strain, NC1, isolated from cultivation soils, was identified as Bacillus subtilis based on the phenotypic characteristics and 16S rRNA gene sequencing. This strain formed a pink color around the colony when cultured on indamine dye formation plates. The production of lipoxygenase by B. subtilis NC1 was influenced by the composition of the medium and linoleic acid concentrations. The optimum temperature and pH for lipoxygenase activity was determined to be 40 ℃ and pH 6, respectively. The enzyme showed relatively high stability at temperatures ranging from 20-50 ℃ and acid-neutral regions. In addition, the lipoxygenase produced by B. subtilis NC1 was able to degrade commercially available oils including sunflower seed oil and Perilla oil. In this study, a useful indigenous bacterium was isolated, and the fundamental physicochemical data of bacterial lipoxygenase giving it industrial potential are presented.