• The KIPS Transactions:PartA
• /
• v.11A no.2
• /
• pp.175-180
• /
• 2004

Generally, as for the multimedia high quality contents, an illegality facsimile is possible without a damage of a quality. Also a distribution of contents duplicated illegality in an Internet is giving a great economic loss to digital contents provider. Therefore, a study for security and efficient distribution of digital contents is required. The most important issues in a design of digital contents distribution system are a user convenience, an execution speed and a security. In this study, we designed digital contents distribution system that used a web caching technology and an encryption/decryption technique on hierarchical structure. The proposed system was the digital contents distribution system that improved a security and execution speed, a convenience of a user. Also it verified performance superiority of a proposed system by an examination.

• Journal of the Korean Wood Science and Technology
• /
• v.31 no.3
• /
• pp.61-69
• /
• 2003

This study investigated the effect of moisture content and loading direction on dowel bearing strength of two types of SCL. Dowel bearing tests of LVL and PSL were conducted with two different MC level, 7.5% and 19%, and two different oriention, L-direction(loading parallel to grain) and X-direction(loading perpendicular to grain). Most of specimens showed typical load-deformation curves and intersected 5% offset line. Failure modes were classified into two categories; spliting(for L-direction specimens) and peeling(for X-direction specimens). Dowel bearing strength generally decreased with increasing MC. The decreasing rate was more significant in X-directon. ESG also decreased with increasing MC, and the ratio of ESG of 7.5% versus 19% was about 1.47. Dowel bearing strength of LVL and PSL in L-direction was higher than that of X-direction. This results indicated that MC and loading orientation had a significant effect on dowel bearing strength of SCL. The average dowel bearing strength of LVL were higher than that of PSL in each loading direction. Two types of probability distribution model were chosen to quantify strength distribution, normal and 2-parameter weibull distribution. The two models showed good agreement with the data, especially in lower tail of the cumulative distribution. Normal and 2-parameter weibull distribution seemed to proper model of the dowel bearing strength for each MC levels.

• The KIPS Transactions:PartC
• /
• v.11C no.6 s.95
• /
• pp.731-738
• /
• 2004

With the increase of digital content usages, the protection for digital content and intellectual property becomes more important. The DRM(digital rights management) technologies are applicable to protect not only any kind of digital contents but also intellectual property. Besides such techniques are required for recorded digital broadcasting contents due to introduction of digital broadcasting techniques and storage devices such as personal video recorder. The conventional protection scheme for broadcasting content is the CAS(conditional access system) by which the access of viewer is controlled on the specific channels or programs. The CAS prohibits the viewer from delivering the digital broadcasting content to other person, so it results in restriction of superdistribution on the digital broadcasting content. In this paper, for broadcast targeting unspecfic many people, we will design the service model of the protection and distribution of digital broadcasting content using encryption and license by employing the concept of DRM. The results of implementation are also shown to verify some functions of each component. An implemented system of this paper has some advantages that the recording of broadcast content is allowed on set-top-box and superdistribution is available by consumer. Hence it provides content providers and consumers with trustworthy environment for content protection and distribution.

• Journal of Distribution Science
• /
• v.13 no.8
• /
• pp.97-104
• /
• 2015

Purpose - This study examines the positive impact of the social distance between producers and users of online content, investigating and analyzing the most popular Web content. In addition, it tries to elicit the matching effect that appears when the individuals'cultural background is consistent with social distance. Research design, data, and methodology - We collected and analyzed actual data about 4,981 videos clips on YouTube, looking at six countries in order to verify the content of this study. Based on the results of the data analysis, the study conducted behavioral measurements on popularity, social distance, culture, and user engagement. The unit of analysis was the content and we collected information about the content producers and the content records. We controlled the views, comments, likes, calendar dates, and ages in the empirical models. The data was collected in 2011, with the records coming from South Korea, Japan, China, U.S., German, and France. A total of 4,980 elements were analyzed in the model. The empirical model estimated is the bivariate negative binomial distribution (NBD) model. Results - It turns out that there is a possibility that the matching effect can be diminished by variables that reflect the psychological involvement of user engagement. This study proposes academic and practical implications based on these research results. This research shows the positive effect of social distance between users and producers on the increased performance of the online content. We find the effect of social distance to be a stronger tendency in collectivism. The collectivists follow their sense of friendship and intimacy in their culture and, the social congruence effect can be found there as well. The effect, however, could erode in a social case where users are motivated by strong intrinsic and psychological factors. In addition, user engagement complicates the process of user decision making regarding the information. Conclusions - This study examines how the differential effects of social distance caused by culture could disappear through user commitment as a complicated user motivation. Some potential implications are as follows. First, a firm in the collectivism culture has to communicate based on the social distance. In fact, most online channels do not have a function that indicates the social distance as measured by favorites or subscribers. This function could help increase the performance of the content in online channels, but this increasing effect can only be found in a collectivist culture. Based on this, the firms have to communicate and announce to users the actual social distance between users and producers. Second, firms should develop a system that discovers the social distance and culture and shows these measures to users and producers, since the congruence effect between social distance and culture is found only for low user engagement. The firms can take the advantage of the congruence effect only for the development of the social distance and culture visualized system.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.7 no.6
• /
• pp.39-48
• /
• 2004

The purpose of this paper was to confirm the application of the equation of the soil-water characteristic curve on an unsaturated soil. To this ends, a series of suction test was conducted on the selected 4 kinds of soil which is located in Korea, using the modified pressure extractor apparatus. And it was carried out to analyze the experimental parameters which can describe the soil-water characteristics, were determined by using the data obtained from the experiment. From the results, it was found that the matric suction was varied according to the grain size distribution, amount of fine grain particle and void ratio. Also it was found that the residual volumetric water content was decreased with the void ratio, but the index related air entry value, the soil parameter related water content and the parameter with residual water content were increased with the void ratio. And the application of equation of the soil-water characteristic curve was confirmed for the various conditions and the various state by the comparison between the volumetric water content measured by the experiment and the predicted values.

• 한국산학경영학회:학술대회논문집
• /
• 2004.11a
• /
• pp.4-22
• /
• 2004

The Internet provides a new distribution channel of digital contents for conventional media firms such as newspaper, magazine and encyclopedia publishers and broadcasting companies with very low marginal production and distribution cost. In comparison to traditional offline channel, there have been various revenue models in online content markets such as advertising model, subscription model, affiliation fee model, etc. In the earlier of the Internet era, most of online content firms provided their services free in order to boost offline revenue or they depend on advertising revenue sources in lieu of attaining revenue from their contents. However, as many online content firms are confronted with many difficulties in attaining revenues from online advertising model, they began to charge their contents. This paper shows why they charge their contents and explores entry conditions when conventional firms enter online content markets. And also this paper discusses managerial implications related to pricing strategies in online content markets.

• Macromolecular Research
• /
• v.16 no.4
• /
• pp.329-336
• /
• 2008

Core/shell ($\pm$)PS/(-)silica nanocomposite particles were synthesized by dispersion polymerization using an amphoteric initiator, 2,2'-azobis [N-(2-carboxyethyl)-2,2-methylpropionamidine] ($HOOC(CH_2)_2HN$(HN=) $C(CH_3)_2CN$=NC $(CH_3)_2C$(=NH)NH $(CH_2)_2COOH$), VA-057. Negatively charged (-6.9 mV) silica was used as the stabilizer. The effects of silica addition time and silica and initiator concentrations were investigated in terms of polymerization kinetics, ultimate particle morphology, and size/size distribution. Uniform hybrid microspheres with a well-defined, core-shell structure were obtained at the following conditions: silica content = 10-15 wt% to styrene, VA-057 content=above 2 wt% to styrene and silica addition time=0 min after initiation. The delay in silica addition time retarded the polymerization kinetics and broadened the particle size distribution. The rate of polymerization was strongly affected by the silica content: it increased up to 15 wt% silica but then decreased with further increase in silica content. However, the particle size was only marginally influenced by the silica content. The zeta potential of the composite particles slightly decreased with increasing silica content. With increasing VA-057 concentration, the PS microspheres were entirely coated with silica sol above 1.0 wt% initiator.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.11 no.2
• /
• pp.27-30
• /
• 1982

The effect of magnesium on the electrolytes distribution and transport in mice was studied using isocalorie and isonitrogenous diets added magnesium salt. The results are summarized as follows: 1. The body weight was the highest value in group C fed with basal diet and 0.4 mg of magnesium per day rather than others. 2. In blood plasma tile content of sodium of group B was higher than others in both male and female. The content of potassium of group B was higher than others in female, and the content of calcium of group B in female and group D in male was higher than others in blood plasma. 3. In case of muscle the content of sodium of group B was higher than others in both male and female. The content of potassium of group B was higher than others in female, but of group C was higher than others in male. The content of calcium of group B was higher than others in female, but of group D was higher than others in male. 4. Magnesium effect on the distribution electrolytes such as sodium, potassium and calcium ions in muscle and blood vessel.

• Magazine of the Korea Concrete Institute
• /
• v.4 no.1
• /
• pp.89-96
• /
• 1992

It is generally known that the frost-resistance of concrete is much affected by the air content in concrete and by the air void system or air distribution. And also the frost-resistance is believed to vary with the stre¬ngth of concrete. This article is prepared to describe, based on experiment, the effect of the air content and the air void system, particularly the effect of the spacing factor, on the freeze-thaw resistance of the high strength conc¬rete. For this purpose, I first worked on Non-AE concrete to make its compressive strength set about 400 to 500 kg/em'. However, the freeze-thaw test on the Non-AE concrete resulted in low durability factor, I.e., 10-2~0%. Thus to enhance the durability, another supplementary step was needed. I used AE admixture. which enhanced durability by changing the air content from 2% to 12%. The frost-thaw test was then performed 500 cycles on the 20 kind of concrete mixtures which differ in unit cement content and in water-cement ratio. Keywords : frost -resistance, air content, air void system, air distribution, spacing factor, freeze-thaw test, dur ability factor. capillary cavity, Linear Traverse Method.

• The Korean Journal of Food And Nutrition
• /
• v.32 no.6
• /
• pp.589-597
• /
• 2019

In this study, 70 kinds of nutritional composition for five bokkeumbap products(spicy chicken, shrimp(saeu), haemul, nakji, and barbecue bokkeumbap) in high-frequency processed foods were analyzed. Raw data of intake amounts were collected from the 7th Korea National Health and Nutrition Examination Survey. Regarding proximate composition, spicy chicken bokkeumbap had lower water content and higher carbohydrate content than other bokkeumbaps, resulting in the highest total calories. The proximate composition of other bokkeumbaps were all distributed within a similar range. Vitamin content differed according to ingredients added to the bokkeumbaps. Haemul bokkeumbap had high content of vitamins B₁ and B₂, nakji bokkeumbap had high content of vitamin C and β-carotene, and barbecue bokkeumbap had high content of total niacin, folic acid, and vitamin A. For mineral content, barbecue bokkeumbap showed the highest content distribution, while nakji bokkeumbap showed the lowest content distribution. Regarding fatty acid and fat content, the highest content of fatty acids, saturated fats, and trans fats was detected in shrimp(saeu) bokkeumbap. For amino acid content, barbecue bokkeumbap showed highest content distribution. These results can be used as salient basic data for a food nutrient composition database and to significantly contribute to consumers' health.