• Polymer(Korea)
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• v.34 no.2
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• pp.159-165
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• 2010

Dipyridine-terminated polystyrenes and polybutadienes were synthesized by the chain endfunctionalization reaction of polystyryllithium (PSLi) and polybutadienyllithium (PBDLi) with di(2-pyridyl) ketone(DPK) using a living anionic polymerization method in the Ar-glove box. Living polymeric lithiums with low molecular weights (Mw=1000~2000 g/mol) were used to investigate the chain end-functionalization yield with DPK and the degree of coupling reaction by the attack of organolithium to the pyridine ring in the presence of TMEDA using GPC, $^1H$-NMR, $^{13}C$ analysis. DPK-terminated PBD exhibited much higher functionalization yield and less amount of coupling reaction compared with DPK-terminated PS. 86% functionalization yield with 9% degree of coupling was obtained when the PBDLi was added dropwise to DPK solution at room temperature. The functionalization yield was increased as the reaction temperature decreased, however, no LiCl effect was observed in this chain end-functionalization reaction with DPK.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.2
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• pp.13-20
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• 1982

The primary purpose of this research paper is to study the nutrition intake status of primary school children and their physique index. Three hundred and ten children of 4th grade, 10 years old, 4 school class in Junbuk province had been selected. Calorie and nutrients were found to be below the recommended level, especially in calcium an vitamin $B_2$. Animal-protein intake averaged about 33% of total protein intake. Total calorie intake were composed of 84% from carbohydrate, 5% from fat and 11% from protein in the case of boys. The girls were 83%, 6%, 11%, respectively. The staple of lunch-boxes for boys supplied 84% of RDA in calorie, 66%, in total-protein 38%, calcium, 32%, Iron, 56%, vitamin $B_1$, 37%, vitamin $B_2$ and 63%, in niacin for girls were 82%, 52%, 28%, 37%, 39%, 37%, 51% respectively.

• Korean Institute of Interior Design Journal
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• v.19 no.4
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• pp.90-98
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• 2010

This study intends to understand the change of the library's bookshelves shape, composition and arrangement based on the social-culture in each period. For this purpose, this study analyzes the morphological shift of the library's bookshelves and knowledge information focused on the history of western libraries from the ancient libraries to the modern public libraries before the 20th century. And the results are follows. 1) We can make sure that the changes of the library's bookshelves are based on the environmental factors like social cultural political factors and also understand that the knowledge information are developed based on the function which is decided by the needs of the times and the serious necessities of users. With this reason, the morphology and the function of the library's bookshelves have been changed. 2) The characters and meanings of the library's bookshelves are changed with the times from movable type to fixed type, from closing type to opening type, from privileged use to public use, from religious contents to general scientific contents. 3) The morphology of the library's bookshelves are shifted from cylindrical box to Chest type Press type and Lectern system, Stall system, Wall system and advanced to Mixed(Stall+Wall) system. 4) The construction and arrangement methods of the library's bookshelves are determined by the convenience and efficiency of the installation for the perusal environments as well as the regarding to the social-cultural factors. The arrangement criteria are determined by the security topics in the earlier stage, after that determined by the lightening topics and nowadays the access topics to the information. These analysis results are very useful to research the technology of the library's bookshelves to be changed continuously and also to forecast the morphology of the library's bookshelves can be planned in the spaces of the future libraries.

• 한국가시화정보학회:학술대회논문집
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• 2005.12a
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• pp.93-98
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• 2005

The mean and RMS velocity field of the respiratory gas flow in tile human airway was studied experimentally by particle image velocimetry(PIV). Some researchers investigated the airflow for the mouth breathing case both experimentally and numerically. But it is very rare to investigate the airflow of nose breathing in a whole airway due to its geometric complexity. We established the procedure to create a transparent rectangular box containing a model of the human airway for PIV measurement by combination of the RP and the curing of clear silicone. We extend this to make a whole airway including nasal cavities, larynx, trachea, and 2 generations of bronchi. The CBC algorithm with window offset (64*64 to 32*32) is used for vector searching in PIV analysis. The phase averaged mean and RMS velocity distributions in Sagittal and coronal planes are obtained for 7 phases in a respiratory period. Some physiologic conjectures are obtained. The main stream went through the backside of larynx and trachea in inspiration and the frontal side in expiration. There exist vortical motions in inspiration, but no prominent one in expiration.

• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.5
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• pp.53-61
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• 1995

Analyses of subsurface drainage effects of farmland with respect to pipe and envelop material are made by the laboratory experiments using soil box to give basic information for the subsurface drainage system planning and design. Three different diameter PVC perforated pipes and a mesh pipe are used with envelop materials such as sand, rice bran, and crushed stone. Steady state subsurface drainage flow rate increased as envelop material changed from sand to rice bran and crushed stone. This indicates that as the hydraulic conductivity of the envelop material increases, the drainage flow rate increases. On the other hand, for a given envelop material, the mesh pipe which has the largest openning area shows the largest flow rate while small diameter PVC pipes show small flow rates. This tells that as the openning area and pipe diameter increase, the flow rate increases, too. Therefore, selection of pipe and envelop material should be made in accordance with the design drainage flow rate. Unsteady state subsurface drainage flow rate with respect to time differs for different envelop material. In case the sand was used as an envelop material, the small diameter PVC pipes show larger flow rates than the large diameter PVC pipe and mesh pipe. When the rice bran was used, the mesh pipe shows the largest flow rate, while small diameter pipes show smaller flow rates. In case the crushed stone was used as an envelop material, the large diameter PVC pipe and mesh pipe show larger flow rates, while small diameter pipes show a little bit smaller flow rates. However, the variation of flow rates among different pipes is the smallest when the crushed stone is used. The flow rate curve with respect to the pipe changes little for the crushed stone envelop which has a large hydraulic conductivity, while that changes much for the sand and rice bran envelops. However, it is difficult to draw a consistent relationship between the drainage flow rate and pipe for all the envelop materials. Since the subsurface drainage experiments are made only under the restricted laboratory condition in this study, further study including field experiment is required.

• Journal of the Korea Convergence Society
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• v.11 no.10
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• pp.81-88
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• 2020

This purpose of this study is to develop content that enables repetitive carving practice of the maxillary right central incisor (MRCI) based on augmented reality (AR). For a step-by-step practice of achieving the tooth shape, after creation of the storyboard from the square box shape in step 1 to the completed MRCI block in step 16, three-dimensional (3D) modeling data reflecting the characteristics of the mesial, distal, lingual, and labial surface of the MRCI were generated. An application was built in which 3D modeling data were output on the screen of the learner's mobile device, and image markers suitable for 3D modeling in steps 1 to 16 of the MRCI model were respectively generated. Using this information, the learner could carve a high-quality MRCI by repeatedly performing the tooth shape carving exercises. With AR, we intend to contribute to improved tooth morphology carving skills by linking the theory and practical techniques for a beginners in dentistry.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.355-365
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• 1997

Macrozoobenthic community structure was studied on the mud-tidalflat around Mokpo coastal area, Korea, from September 1995 to May 1996. Ten sampling stations were chosen along the 1km transect with a 100 m intervals. Triple macrozoobenthos sampling were conducted with a stainless box core sampler (size $13{\times}22{\times}30$ cm) at each station on the seasonal basis. A total of 119 species of macrobenthos was sampled with a mean density 2,357 $ind./m^2$ and biomass of 180. 94 $g/m^2$ during the study period. Of these species, there were 51 species of mollusce (43%), 36 of crustaceans (30%), 27 of polychaetes (23%). Molluscs were density-dominant faunal group with a mean density of 1,804 $ind./m^2$, comprising of 75% of the total density of the benthic animals. It was followed by polychaetes with 347 $ind./m^2$ (15% of the total density). Molluscs were biomass-dominant faunal group with a mean biomass of 147.51 $g/m^2$ (82% of the total biomass). The number of species, abundance and biomass showed increasing trends toward the lower intertidal stations from the higher stations. Major dominant species were Musculista senhousia (bivalve), Capitellidae spp. (polychaetes) with a density of 1,640 $ind./m^2$ and 179 $ind./m^2$ , respectively. The density of M. senhousia was more than 63% of the total density of benthic organism on the tidal area. Small gastropod Cerithideopsilla umumriensis was another dominant epifaunal species between st.1 and 2 with a mean density of 100 $ind./m^2$. Cluster analysis showed that the benthic community could be divided into three stational groups, that is, upper, middle and lower groups by the exposure duration.

• Journal of the Korean Institute of Gas
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• v.10 no.2 s.31
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• pp.1-6
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• 2006

In this study we proposed on effect of the photodecomcomposition of coated nanofiber by $Pd/TiO_2$ for the removal of formaldehyde gas as indoor air pollutant. The photocatalytic reactor was setup in the inside of rectangular box (volume 2 l), UV lamp and the coating nanofiber with $Pd/TiO_2$. This study investigated the reaction rate and the adsorption constant of Langmuir-Heinshelwood, conversion of formaldehyde gas on temperature ($40^{\circ}C{\sim}80^{\circ}C$), effect of conversion (%) under different concentration, and effect of conversion (%) with humidity level on added $SO_2$ gas. As results, the rate constant (k) and adsorption constant (ft) were 114.94ppmv/min, $0.0036ppmv^{-1}$, respectively. and the conversion (%) of formaldehyde gas on temperature ($40^{\circ}C{\sim}80^{\circ}C$) was decreased to about 24%, compare with the first conversion (%). In conversion effect of increasing humidity levels, the presence of sulfur dioxide further decreased than without sulfur dioxide. the decreasing reason of conversion with presence sulfur dioxide judged as a cause of interference factor on the decrease of contact chance with photocatalysts.

• Journal of Korea Multimedia Society
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• v.12 no.4
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• pp.608-615
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• 2009

As RFID tag prices have rapidly been declining because of the advance of RFID technology, each tag is attached to an individual item, not a packing box only, for managing the item much more precisely. However, some mechanisms are essential to handle a very large amount of tag data quickly because readers and middlewares processing RFID data have limited hardware resources. In this paper, we design and implement a new mobile agent-based distributed software tools to satisfy this requirement efficiently. These tools provide a convenient environment enabling required data to be pre-processed repeatedly in transit by transferring a mobile agent including its specified data collection policy to numerous mobile readers. This behavior can significantly reduce the elapsed time required for processing huge volumes of tag data at the readers and middlewares with their very high recognition rates compared with the existing one to process the data by fixed readers after having arrived at the destination

• Journal of Korea Multimedia Society
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• v.12 no.9
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• pp.1201-1209
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• 2009

Recently, the convergence of the telecommunications industry through the development of network media has brought along interactive data services in addition to the traditional broadcast services by providing direct connections between the users and the broadcasters. This can be easily achieved by the combination of existing network technology and multimedia technology, but in reality, as seen in the actual implementation of IPVT, it's difficult to provide satisfactory levels of service to users due to issues of network bandwidth and problems of streaming system. In particular, a network which is able to fully support Qos/QoE, and also a fast enough channel changing technology that is satisfactory to the user, are prerequisites for IPTV success. Therefore this thesis proposes a fast channel changing technique to delivery enhanced IPTV user experience. Recent IP set-top-boxes use only a small portion of the CPU to feed Ethernet packets to the hardware decoder and play them. Thus, by making IP set-top-boxes share cached channel information and content with each other, reducing the load on the server and enhancing the channel changing time is made possible.