• Journal of KIISE:Information Networking
• /
• v.32 no.3
• /
• pp.415-426
• /
• 2005

Wireless internet, which becomes a hot social issue, has limitations due to the following characteristics, as different from wired internet. It has low bandwidth, frequent disconnection, low computing power, and small screen in user terminal. Also, it has technical issues to Improve in terms of user mobility, network protocol, security, and etc. Wireless internet server should be scalable to handle a large scale traffic due to rapidly growing users. In this paper, wireless internet proxy server clusters are used for the wireless Internet because their caching, distillation, and clustering functions are helpful to overcome the above limitations and needs. TranSend was proposed as a clustering based wireless internet proxy server but it has disadvantages; 1) its scalability is difficult to achieve because there is no systematic way to do it and 2) its structure is complex because of the inefficient communication structure among modules. In our former research, we proposed the All-in-one structure which can be scalable in a systematic way but it also has disadvantages; 1) data sharing among cache servers is not allowed and 2) its communication structure among modules is complex. In this paper, we proposed its improved scheme which has an efficient communication structure among modules and allows data to be shared among cache servers. We performed experiments using 16 PCs and experimental results show 54.86$\%$ and 4.70$\%$ performance improvement of the proposed system compared to TranSend and All-in-one system respectively Due to data sharing amount cache servers, the proposed scheme has an advantage of keeping a fixed size of the total cache memory regardless of cache server numbers. On the contrary, in All-in-one, the total cache memory size increases proportional to the number of cache servers since each cache server should keep all cache data, respectively.

• Journal of Korean Society for Geospatial Information Science
• /
• v.23 no.1
• /
• pp.73-79
• /
• 2015

Recently, BIM proliferates at high speeds so that BIM planning is trying to be used in various kinds of engineering. However, when using different software during design phase and construction phase, the problem of mutual compatibility is coming out. Even the BIM technology has been used or the practical applicability has been made into result, it would be fair to say that BIM has limitations in the visual level. In this research, it is meaningless to obtain the BIM result as the primary purpose. As the usefulness of it is judged incomplete, we committed to master the trend and problems of terrain spatial information systems and BIM. Furthermore, the plan of building the BIM in the civil field, especially the civil-BIM based on the technology ofterrain spatial information has been presented. It can be judged through this research that the high-capacity DB of BIM occurred during the whole process may cause poor performance of the following stage the structure system which connects the terrain spatial information and civil-BIM. In order to manage the optimal full cycle, the spatial analysis technology of the stages after choosing the DB has been described.

• Journal of the Korean Chemical Society
• /
• v.33 no.3
• /
• pp.287-294
• /
• 1989

The optimum condition for the separation of priority pollutant phenols using isocratic elution has been determined. The elution behavior of eleven phenols has been also studied to interpret the retention. The reversed phase liquid chromatographic methods were performed on a ${\mu}$-Bondapak $C_{18}$ column with methanol-water, acetonitrile-water, and THF water mixtures as mobile phases. The COF method, where Snyder's solvent triangle concept was combined with a mixture-design statistical technique, was used to optimize the strength and selectivity of solvents for the separation of phenols. The optimum solvent composition, which gives a complete separation of eleven phenols, was found to be $MeOH:ACN:H_2O$ = 7:40:53. The plots of ln k' vs. -${\Delta}H^{\circ}$ and ${\Sigma}{\pi}$ of phenols showed relatively good linearities. Effect of van der Waals volume, pi-energy and hydrogen bonding on the retention of phenols were investigated. The following equation with the correlation coefficient of 0.9927 for ACN-water solvent system was obtained; $log^{k'}=2.515{\times}10^{-2}VWV-1.301{\times}10^{-1}E-3.674{\times}10^{-1}$

• Korean journal of communication and information
• /
• v.56
• /
• pp.71-85
• /
• 2011

This thesis reviews the process in which the regulation systems against ownership concentration of newspapers established with the opportunity of legislation of the periodical act in 1987 was reinforced as they were all amended to the newspaper act in 2005 and as they were again amended in 2009 it came to confront crisis in the aspect of press law legislation history. The regulation systems against ownership concentration of newspapers established based on the principle of legality of newspaper function in the Clause 3, the Article 21 of Constitution was reinforced as the newspaper act in 2005 and in 2006 they began to shrink following the Constitution Court decision against newspaper act. As newspaper act and broadcast act are revised in 2009, regulation against combining the management of newspapers with broadcast and regulation against owning multiple number of newspapers came not to exist. Because in this process, the opposition party also allowed limited cross-ownership of newspaper and broadcast, it can be said that the system of newspaper ownership regulation confronted the crisis of dissolution. The instruction of regulation alleviation in a short period of time in spite of the fact that regulation alleviation which allows cross-ownership of newspaper and broadcast is the matter of policy that should be decided after long-term review of the change of media environment and the progress of the power of domination of public opinion is dangerous. Newspapers are strong media with terrestrial broadcast in formation of public opinion on politics. It's because it is difficult to ignore the worry that the power of domination of public opinion of the newspapers which are in oligopoly of newspaper public opinion market can be spreaded to the territory of report broadcast. From the point of view that there is probability for democracy to be ultimately threatened due to the shrink of political Darwinism caused by concentration of media ownership, the alleviation of ownership concentration of newspapers should have premise of long-term social discussion.

• Journal of Korea Water Resources Association
• /
• v.31 no.6
• /
• pp.727-739
• /
• 1998

The main objectives o reservoir optimal operation can be described as follows : maximization of the benefits through optimal allocation of the limited water resources for various purpose; minimization of t도 costs by the flood damage in potential damaging regions and risk of dam failure, etc. through safe drainage of a bulky volume of excessive water by a proper reservoir operation. Reviewing the past research works related to reservoir operation, we can find that the study on the matter of the former has been extensively carried out in last decades rather than the matter of the latter. This study is focused on developing a methodology of optimal reservoir operation for flood control, and a case study is performed on the Chungju multipurpose reservoir in Korea. The final goal of the study is to establish a reservoir optimal operation system which can search optimal policy to compromise two conflicting objectives: downstream flood damage and dam safety-upstream flood damage. In order to reach the final goal of the study, the following items were studied : (1)validation of hydrological data using HYMOS: (2)establishment of a downstream flood routing model coupling a rainfall-runoff model and SOBEK system for 1-D hydrodynamic flood routing; (3)replication of a flood damage estimation model by a neural network; (4)development of an integrated reservoir optimization module for an optimal operation policy.

• Nuclear Engineering and Technology
• /
• v.15 no.3
• /
• pp.179-187
• /
• 1983

The pH of containment spray and sump water following a LOCA for KNU 5'||'&'||'6 and KNU 1 was calculated to see if pH design criteria of containment spray system established by USNRC were met. The pH calculations have been made for the two cases; maximum pH and minimum pH. For KNU 5'||'&'||'6, results showed that long term sump pH values calculated for the maximum pH and minimum pH case well met the pH requirement of at least 8.5 and spray pH for the maximum case slightly exceeded the range of design criteria (8.5 to 11.0). For KNU 1, pH requirement of long term sump pH was also met, however, spray pH value for the maximum pH case was very largely greater than that of current pH requirement. (No pH requirement of containment spray water has been established at the time of designing KNU 1) In order to find the design parameters of containment spray system which are expected to meet the spray pH requirement, several calculations were wade, by changing the input parameters to "LCCAPH". Finally, it was shown that the boric acid concentration in RWST (refueling water storage tank), which was the primary sources of containment spray water during injection mode, be maintained the range of 2750 ppm to 2850 ppm, or tile flow rate of NaOH added to spray water he kept between 10 gpm to 24 gpm.

• Journal of Life Science
• /
• v.18 no.1
• /
• pp.129-135
• /
• 2008

Paraquat (1,1-dimethyl 4,4' -dipyridium dichloride; PQ) is a kind of herbicide. Terminalia chebulae (TC) has been used as a medicine in China and in Korea for treating illnesses such as diarrhea, collapsed anus, spasmodic, diphtheria, asthma etc.. This study was to examin new physiological activities of methanol extract of TC (TCM) on the toxicity of PQ. It was observed biochemical effects on the toxicity of PQ in kidney and lung tissues after treatment orally administered 100, 200, 300 mg/kg of TCM daily for two weeks. In the experiment related to the toxicity of PQ, we got following results: renal and pulmonary lipid peroxide contents, activities of aminopyrine N-demethylase, aldehyde oxidase and xanthine oxidase were significantly increased in control group as compared with normal group, in the treatment of TCM the values were decreased as compared with control group. Activities of superoxide dismutase, catalase and glutathione peroxidase which are free radical scavenging enzymes were also increased in control group as compared with normal goup, but were decreased in TCM group as compared with control group. Collagen content and glucose-6-phosphatase activity in lung tissue were increased in control group as compared with normal, but was decreased in TCM group as compared with control group. From these results, we concluded that TCM can playa role as an effective agent to decrease toxicity of PQ.

• The Korean Journal of Food And Nutrition
• /
• v.21 no.2
• /
• pp.243-255
• /
• 2008

This study was performed to offer basic data base on traditional Korean festival foods for a traditional Korean food data integration system, that is based on literature reviews. The Korean lunar calendar has seasonal divisions reflecting traditional Korean holidays. In the past, there were many customs corresponding to emotions, and foods were in accordance with customs, festivals, and seasons. Today, we are well aware of the traditional Korean foods of New Year's Day(Seollal), the Korean Harvest Festival(Chuseok), the First Full Moon Day(Jeongwol Daeboreum), the Winter Solstice(Dongji), and the hottest summer day(Sambok). However, many other traditional Korean holidays are disappearing from the modem Korean life-style. This study made the following classifications for traditional Korean festivals. Seollal(Seol), Ipchun, and Jeongwol Daeboreum in January; Junghwajeol in February; Samjinnal in March; Hansik and Chopail in April; Dano in May; Yudu and Sambok in June; Chilseok and Baekjung in July; Chuseok in August; Jungyangjeol in September; Siwolmuoil in October; Dongji in November; and Napil and Seotdal Geumeum in December. The familiar traditional Korean festival foods are as follows: Seollal's festival foods consist of 5 main dishes, 35 side dishes, 12 kinds of tteok lyou, 21 kinds of hangwa lyou, 2 kinds of emchong lyou, and 3 kinds classified as others; this includes tteokguk, manduguk, galbijjim, sinseollo, jeon, pyunyuk, kimch, tteok, sikhe, sujunggwa, fruits, and seju on Seollal. The festival foods for Jeongwol Daeboreum consist of 3 main dishes, 27 side dishes, 5 kinds of tteok lyou, 3 kinds of hangwa lyou, 4 kinds of emchung lyou, and 3 kinds classified as others; this includes ogokbap, mugeunnamul, yaksik, yumilkwa, wonsobyung, guibalgisul, and burum on Jeongwol Daeboreum. The festival foods for Sambok consist of 6 main dishes, 18 side dishes, 4 kinds of tteok lyou, 3 kinds of eumchung lyou, and 2 kinds classified as others; this includes yukgaejang, imjasutang, youngyejjim, tteoksudan, santtalgihwaschae, and subak on Sambok. Chuseok's festival foods consist of 4 main dishes, 22 side dishes, 18 kinds of tteok lyou, 6 kinds of hangwa lyou, 4 kinds of eumchung lyou, and 3 kinds classified as others; this includes oryeosongpyeon, toranatang, garijjim, dakjjim, namuls, tteok lyou, baehwachae, and fruits on Chuseok. The festival foods for Dongji consist of 6 main dishes, 6 side dishes, 7 kinds of tteok lyou, 1 kind of hangwa lyou, 2 kinds of eumchung lyou, and 1 kind classified as others; this includes patjug, jeonyak, and dongchimi on Dongji. Based on these data, it is recommended that knowledge of traditional Korean festival foods be handed down, preserving and develop their excellence and to further scientific studys.

• Food Science of Animal Resources
• /
• v.40 no.5
• /
• pp.852-859
• /
• 2020

The muscle stem cells of domestic animals are of interest to researchers in the food and biotechnology industries for the production of cultured meat. For producing cultured meat, it is crucial for muscle stem cells to be efficiently isolated and stably maintained in vitro on a large scale. In the present study, we aimed to optimize the method for the enrichment of pig muscle stem cells using a magnetic-activated cell sorting (MACS) system. Pig muscle stem cells were collected from the biceps femoris muscles of 14 d-old pigs of three breeds [Landrace×Yorkshire×Duroc (LYD), Berkshire, and Korean native pigs] and cultured in skeletal muscle growth medium-2 (SkGM-2) supplemented with epidermal growth factor (EGF), dexamethasone, and a p38 inhibitor (SB203580). Approximately 30% of total cultured cells were nonmyogenic cells in the absence of purification in our system, as determined by immunostaining for cluster of differentiation 56 (CD56) and CD29, which are known markers of muscle stem cells. Interestingly, following MACS isolation using the CD29 antibody, the proportion of CD56⁺/CD29⁺ muscle stem cells was significantly increased (91.5±2.40%), and the proportion of CD56 single-positive nonmyogenic cells was dramatically decreased. Furthermore, we verified that this method worked well for purifying muscle stem cells in the three pig breeds. Accordingly, we found that CD29 is a valuable candidate among the various marker genes for the isolation of pig muscle stem cells and developed a simple sorting method based on a single antibody to this protein.

• Journal of Korean Society for Geospatial Information Science
• /
• v.22 no.1
• /
• pp.3-12
• /
• 2014

Cadastre is a set of activity registering diverse land information in national scope land management works. A nation examine land information and register it in a cadastral book, and must update data when necessary to properly maintain the information. Currently, local governments execute work about parcels of land alternation by manual work based on KLIS road map. Therefore, it takes too much time-consuming and makes problem as missing lots of parcels of land alternation. This study suggests the method selecting the parcels of land alteration for Jinan-Gun of Jeollabuk-Do using the GIS spatial overlay and the following results are as belows. Firstly, the manual work on the parcels of land alteration was greatly improved through automatically extracting the number and area of parcels according to the land classification and ownership by GIS spatial overlay based on serial cadastral maps and KLIS road lines. Secondly, existing work based on KLIS road lines could be advanced by analyzing the parcels of land alternation using the actual-width of the road from new address system to consider all road area for study site. Lastly, this study can supply efficient information in determining the parcels of land alternation consistant with road condition of local governments by analyzing the number and area of parcels according to the land classification and ownership within various roadsides ranging from 3m, 5m, and 10m by GIS buffering method.