• The Journal of Korean Institute of Communications and Information Sciences
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• v.39B no.11
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• pp.730-742
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• 2014

In the case of On-demand routing protocol in cognitive radio ad-hoc networks, broadcasting of control packets may occur common control channel overload and packet collisions during the routing procedure. This situation is to increase the overhead of path finding and also limited to find the accurate and reliable path. Since reliable channel and path finding is restricted, path life time is shorten and path reliability is reduced. In this paper, we propose a new routing algorithm that reduces control channel overhead and increases path life time by considering the probability of appearance of primary user and channel status of neighbor nodes. Each node performs periodic local sensing to detect primary user signal and to derive primary user activity patterns. The probability of primary appearance on the current channel and the channel status can be obtained based on the periodic sensing. In addition, each node identifies the quality of the channel by message exchange through a common channel with neighbor nodes, then determines Link_Levels with neighbor nodes. In the proposed method, the Link Level condition reduces the number of control messages that are generated during the route discovery process. The proposed method can improve path life time by choosing a path through Path_Reliability in which stability and quality are weighted depending on the location. Through simulation, we show that our proposed algorithm reduces packet collisions and increases path life time in comparison with the traditional algorithm.

• The Journal of Fisheries Business Administration
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• v.22 no.1
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• pp.53-75
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• 1991

The objectives of this study are to conceptualize theoretically and to examine empirically the interrelationships among channel member's satisfaction, dependence, and performance being immanent between dealing partners, by integrating behavioral and economic approach to explain comprehensively the interrelationship between dealing partners in conventional marketing channel which have not studied in previous studies. To attain above objectives, latent variables and observed variables which had been immanent between licenced dealers and wholesalers in fish marketing channel were found out by exploratory study, and pre-test was conducted to select the proper variables, and then the model which could explain the interrelationships among the variables was set up. Three categories of varables were considered in this study. Namely, economic and noneconomic factors were identified as independent variable, the degree of satisfaction and dependence to dealing partner as intervening variable, and performance as dependent variable. The data for the study was obtained from a survey questionnaire of 214 licenced dealers who work in Pusan, Yusoo, and Kunsan and 190 wholesalers who work in whole country. Among them, 264 anayzable questionnaires(including 154 licenced dealers and 110 wholesalers)were collected. Statistical procedure to analyze the data was carried out by LISREL version 7. Major findings obtained from the results of the analysis are as follows. First, economic variables have a great influence on the degree of both licenced dealers' and wholesalers' satisfaction. Among economic variables, the degree of keeping wholesalers' payment date have greater influence on the degree of licenced dealers' satisfaction, and licenced dealers' faculty being able to send good fish in quality have greater influence on the degree of wholesaler's satisfaction than other variables. In short, licenced dealers make great account of wholesalers' payment, and wholesalers make great account of licenced dealers' faculty being able to send good fish in quality in dealing relationship. Second, noneconomic variables have more relevance to the degree of dependence in both sides than economic variables. This means that noneconomic variables as well as economic variables can be a factor to keep up the dealing relationship. Third, the degree of satisfaction and dependence have influence on performance in both sides. In the licenced dealers' side, the degree of dependence have greater influence on performance than the degree of satisfaction, on the other hand, in wholesalers' side, the degree of satisfaction have greater influence on performance than the degree of dependence. This means that wholesalers can easily substitute their dealing partner for another licenced dealer comparatively.

• Journal of the Korea Concrete Institute
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• v.22 no.3
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• pp.409-417
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• 2010

This paper discusses a series of experiments including material improvement in order to ensure quality of grouting for the post-tensioned structure. In prestressed concrete, grouting refers to the construction procedure of filling empty space of duct enclosing with strands using cementitious material, To date, adequate quality control of the grouting has not been established in Korea because the relationship between the grouting and durability of post-tensioned structure is not well-recognized. The Korean standard does not consider the important material characteristic, wick effect, which is caused by strands in the ducts and current standard testing method unlikely quantify reasonable material segregation. As a result, the grout material, which meets the current material standards, may exhibit excessive bleeding water or shrinkage during construction. In this study, international codes and standards related to grouting were surveyed. The ratio of constituents and novel admixtures were suggested to meet equivalently with these standards. Performance of this enhanced grout was compared to common domestic grout using the international standard testing method. A series of mock-up specimens considering geometry of PC beam was constructed and grout flow pattern was observed as the grout was injected. It was observed that the grouting performance was highly influenced by material properties and filling characteristic can be varied depending on geometry of ducts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.10
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• pp.1438-1443
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• 2009

The effects of adding additives such as gum, emulsifier, and enzyme both individually and as mixtures to frozen rice bread dough on baking quality were examined. Rice flours containing 17% vital gluten, and gum/emulsifier/enzyme blends were mixed and stored in a freezer at $-20^{\circ}C$ for 4 weeks. The rice doughs were removed from the freezer, thawed, and then followed the rice baking procedure. The dough freezing and frozen storage resulted in decreased volume of rice bread. The addition of guar gum/sodium stearoyl lactylate (SSL)/fungal $\alpha$-amylase blend improved volume of the rice bread obtained from rice dough during frozen storage. An increase in firmness of crumb was observed in rice breads during 3 days of storage at $25^{\circ}C$. Compared to the control dough without additives, addition of guar gum/ SSL blend or guar gum/ SSL/ fungal $\alpha$-amylase blend into frozen dough significantly reduced the crumb firmness of rice bread, indicating a significant antistaling effect.

• Journal of Preventive Medicine and Public Health
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• v.21 no.1 s.23
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• pp.195-206
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• 1988

Two major issues of the blood bank management are quality assurance and inventory control. Recently, in Korea blood donation has gained popularity increasingly to allow considerable improvement of the quality assurance with respect to blood collection, transportation, storage, component preparation skills and hematological tests. Nevertheless the inventory control, the other issue of blood bank management, has been neglected so far. For the supply of blood by donation barely meets the demand, the blood bank policy on the inventory control has been 'the more the better.' The shortage itself by no means unnecessitate inventory control. In fact, in spite of shortage, no small amount of blood is outdated. The efficient blood inventory control makes it possible to economize the blood usage in the practice of state-of-the-art medical care. For the efficient blood inventory control in Korean hospitals, this tudy is to develop formulae forecasting the standard blood inventory level and suggest a set of policies improving the blood inventory control. For this study informations of $A^+$ whole bloods and packed cells inventory control were collected from a University Hospital and the Central Blood Bank of the Korean Red Cross. Using this informations, 1,461 daily blood inventory records were formulated.48 varieties of blood inventory control environment were identified on the basis of selected combinations of 4 inventory control variables-crossmatch, transfusion, inhospital donation and age of bloods from external supply. In order to decide the optimal blood inventory level for each environment, simulation models were designed to calculate the measures of performance of each environment. After the decision of 48 optimal blood inventory levels, stepwise multiple regression analysis was started where the independent variables were 4 inventory control variables and the dependent variable was optimal inventory level of each environment. Finally the standard blood inventory level decision rule was developed using the backward elimination procedure to select the best regression equation. And the effective alternatives of the issuing policy and crossmatch release period were suggested according to the measures of performance under the condition of the standard blood inventory level. The results of this study' were as follows ; 1. The formulae to calculate the standard blood inventory level($S^*$)was $S^*=2.8617X(d)^{0.9342}$ where d is the mean daily crossmatch(demand) for a blood type. 2. The measures of performace - outdate rate, average period of storage, mean age of transfused bloods, and mean daily available inventory level - were improved after maintenance of the standard inventory level in comparison with the present system. 3. Issuing policy of First In-First Out(FIFO) decreased the outdate rate, while Last In-First Out(LIFO) decreased the mean age of transfused bloods. The decrease of the crossmatch release period reduced the outdate rate and the mean age of transfused bloods.

• Korean journal of communication and information
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• v.28
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• pp.171-218
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• 2005

There is a original routine on dealing the first edition newspaper in Korea. Korean national morning newspapers print about 0.5% of total circulation as the first edition and sale those only in Seoul where the newspapers is published. The dead line of first edition is even about 5 pm. According to this routine which couldn't be found in the advanced western nations, like UK, USA etc., there can be some original characteristics and problems on the contents of Korean national morning newspapers. The present study investigated what the characteristics and problems means on the quality of newspaper and the free flow of diverse informations and opinions. Content analysis comparing the first edition to the last edition of 8 national morning newspapers is used to reveal the original characteristics and problems. Major findings in the result of the content analysis are three. First, the quality of the newspapers is damaged by the early dead line. Second, Inter-media agenda setting, which minor papers follow major papers on not only contents but also tone & manner, is manifest. Third, the early time publishing of the first edition allow the reported group including government and business sorter to take time to do make some negotiations on the articles about them, in which procedure even about 40% of total observed articles are changed(eg. removed, replaced, modified).

• Korean Journal of Fisheries and Aquatic Sciences
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• v.5 no.3
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• pp.97-103
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• 1972

In this paper, the effects of some additives to the quality of fish cake such as salt, polyphosphate, and starch were tested. Besides, that of washing and alterative heating procedure were also discussed. From the result of quality test by measuring jelly strength and sensory evaluation the product was quite palatable to common, and the addition of salt and starch as 3 and 5 to 15 percent respectively, resulted in the best jelly strength of the product, it was markedly enforced when a small amount of polyphosphate ($0.3\%$) was added. It is suggested for a processing method of carp meat fish cake that meat is to be bleached by wasing at least 8 times repeatedly with tenfold tap water by volume of meat, and that the meat is previously chilled at 2 to $3^{\circ}C$ for so minutes and ground thoroughly with addition of 3 percent of salt, 5 to 15 percent starch, and 0.3 percent polyphosphate, and finally heat processed by two stages: at first, heated for 1 hour at $35^{\circ}C$ and alteratively heated for 30 minutes at $90^{\circ}C$ as the final.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.3
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• pp.14-20
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• 2018

Electric vehicles are environmentally friendly because they emit no exhaust gas, unlike gasoline automobiles. However, since they are driven by the electric power from batteries, the distance they can travel based on a single charge depends on their energy density. Therefore, the lithium-ion battery having a high energy density is a good candidate for the batteries of electric vehicles. Since the electrode is an essential component that governs their efficiency, the electrode manufacturing process plays a vital role in the entire production process of lithium-ion batteries. In particular, the coating process is a critical step in the manufacturing of the electrode, which has a significant influence on its performance. In this paper, we propose an innovative process for improving the efficiency and productivity of the coating process in electrode manufacturing and describe the equipment design method and development results. Specifically, we propose a design procedure and development method in order to improve the core plate coating quality by 25%, using a technology capable of reducing the assembly margin due to its high output/high capacity and improving the product capacity quality and assembly process yield. Using this method, the battery life of the lithium-ion battery cell was improved. Compared with the existing coating process, the target loading level is maintained and dispersed to maintain the anode capacity (${\pm}0.4{\rightarrow}{\pm}0.3mg/cm^2r$ reduction).

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.249-258
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• 2010

This study seeks to improve NFRDI Serial Oceanographic observation (NSO) system which has been operated at current observation stations in the Korean Seas since 1961 and suggests the direction of NSO for practical use of Korean operational oceanographic system. For improvement, data handling by human after CTD (Conductivity-Temperature-Depth) observation on the deck, data transmission, data reception in the land station, and file storage into database need to be automated. Software development to execute QA/QC (Quality Assurance/Quality Control) of real-time oceanographic observation data and to transmit the data with conversion to appropriate format automatically will help to accomplish the automation. Inmarsat satellite telecommunication systems with which have already been equipped on board the current observation vessels can realize the real-time transmission of the data. For the near real-time data transmission, CDMA (Code Division Multiple Access) wireless telecommunication can provide efficient transmission in coastal area. Real-time QA/QC procedure after CTD observation will help to prevent errors which can be derived from various causes.

• Journal of Pharmaceutical Investigation
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• v.35 no.3
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• pp.137-142
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• 2005

A rapid, selective and sensitive reversed-phase HPLC method for the determination of glipizide in human serum was validated and applied to the pharmacokinetic study of glipizide. Glipizide and internal standard, tolbutamide, were extracted from human serum by liquid-liquid extraction with benzene and analyzed on a Nova Pak $C_{18}\;60{\AA}$ column with the mobile phase of acetonitrile-potassium dihydrogen phosphate (10 mM, pH 3.5) (4:6, v/v). Detection wavelength of 275 nm and flow rate of 0.7 ml/min were fixed for the study. The assay robustness for the changes of mobile phase pH, organic solvent content, and flow rate was confirmed by $3^3$ factorial design using a fixed glipizide concentration (500 ng/ ml) with respect to its peak area and retention time. And also, the ruggedness of this method was investigated at three different laboratories using same quality control (QC) samples. This method showed linear response over the concentration range of 10-1000 ng/ml with correlation coefficient greater than 0.999. The lower limit of quantitation using 0.5 ml of serum was 10.0 ng/ml, which was sensitive enough for pharmacokinetic studies. The overall accuracy of the quality control samples ranged from 82.6 to 105.0% for glipizide with overall precision (% C.V.) being 1.13-13.20%. The percent recovery for human serum was in the range of 85.2 93.5%. Stability studies showed that glipizide was stable during storage, or during the assay procedure in human serum. The peak area and retention time of glipizide were not significantly affected by the changes of mobile phase pH, organic solvent content, and flow rate under the conditions studied. This method showed good ruggedness (within 15% C.V.) and was successfully used for the analysis of glipizide in human serum samples for the pharmacokinetic studies at three different laboratories, demonstrating the suitability of the method.