• Korean Journal of Animal Reproduction
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• 제24권4호
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• pp.407-417
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• 2000

The present study was to examine effects of various electrical stimulus treatments used for electro-fusion on the preimplantation development of bovine nuclear transfer (NT) embryos with fetal fibroblast cells. Fetal fibroblast cells were isolated from one fetus at day 45 of gestation in Holstein cow, and passaged 3 to 4 times before being transferred into enucleated oocytes. Single fibroblast cells were individually placed into the perivitelline space of enucleated oocytes by using a micromanipulator. At first, the fusion and developmental rates of reconstructed oocytes were compared between different electric stimulation conditions. When fusion of the reconstructed oocyte was induced by different electric pulse periods (15, 30 and 45 $\mu$sec) at a DC pulse of 1.8 kV/cm, 15 (45.5%, 120/264) or 30 $\mu$ sec group (43.9%, 106/241) showed a higher fusion rate than 45 $\mu$sec group (23.2%, 58/250, P＜0.05). However, no difference was detected in the development rate of the fused oocytes to blastocysts between groups. Next experiment was to examine the effects of different electrical field strengths (1.5, 1.8 and 2.1 kV/cm) for 15 $\mu$sec at electrofusion on in vitro development of the NT embryos. As results, there was no difference in the fusion and developmental rates of the NT embryos between electrical strength (P＞0.05). Finally, developmental competence of bovine NT embryos with somatic cells was compared with IVF-derived embryos. Of enucleated oocytes fused with fibroblast cells, 27.4% (75/274) developed to the blastocyst stage, which is similar to that (24.5%, 58/237) of IVF-derived embryos. However, mean nuclei number of NT blastocysts was smaller than that of IVF-derived blastocysts. Thus, we have established an optimal condition (1.8 kV/cm, 15 $\mu$sec) for electric fusion of bovine NT oocytes with somatic cells. The present study indicates that bovine reconstructed embryos with somatic cells normally develop to blastocyst stage in vitro, although having smaller nuclei numbers of blastocysts as compared to IVF-derived embryos.

• Journal of the Korea Organic Resources Recycling Association
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• 제16권2호
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• pp.57-65
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• 2008

Wastewater containing strong organic matter is very difficult to treat by utilizing general sewage treatment plant. but the wastewater is adequate to generate biomass energy (bio-gas; methane gas) by utilizing anaerobic digestion. EcoDays Plug Flow Reactor (E-PFR), which was already proved as an excellent aerobic wastewater treatment reactor, was adapted for anaerobic food wastewater digestion. This research was performed to improve the efficiency of bio-gas production and to optimize anaerobic wastewater treatment system. Food wastewater from N food waste treatment plant was applied for the pilot scale experiments. The results indicated that the efficiency of anaerobic wastewater treatment and the volume of bio-gas were increased by applying E-PFR to anaerobic digestion. The structural characteristics of E-PFR can cause the high efficiency of anaerobic treatment processes. The unique structure of E-PFR is a diaphragm dividing vertical hydraulic multi-stages and the inversely protruded fluid transfer tubes on each diaphragm. The unique structure of E-PFR can make gas hold-up space at the top part of each stage in the reactor. Also, E-PFR can contain relatively high MLSS concentration in lower stage by vertical up-flow of wastewater. This hydraulic flow can cause high buffering capacity against shock load from the wastewater in the reactor, resulting in stable pH (7.0~8.0), relatively higher wastewater treatment efficiency, and larger volume of bio-gas generation. In addition, relatively longer solid retention time (SRT) in the reactor can increase organic matter degradation and bio-gas production efficiency. These characteristics in the reactor can be regarded as "ideal" anaerobic wastewater treatment conditions. Anaerobic wastewater treatment plant design factor can be assessed for having 70 % of methane gas content, and better bio-gas yielding and stable treatment efficiency based on the results of this research. For example, inner circulation with generated bio-gas in the reactor and better mixing conditions by improving fluid transfer tube structure can be used for achieving better bio-gas yielding efficiency. This research results can be used for acquiring better improved regenerated energy system.

• Journal of Practical Agriculture & Fisheries Research
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• 제4권1호
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• pp.128-137
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• 2002

This study was conducted to develop the heat exchanger by utilizing the heat energy of underground water(15℃), which might be used for cooling and heating system of the agricultural facilities. We developed the heat exchanger by using the parallel type plat fin tube made of Aluminum(Al 6063), which was named Aloo-Heat(No. 0247164, offered by Korean Intellectual property Office). The trial manufactures were made from Aloo-heat which was 600mm, 700mm length respectively, and It were welded to the end "U" type in order to direct flow of the underground water. The performance test was carried out under the condition of open space and room temperature with the change of flow rate of the underground water and air. The results are as follows. 1. The trial manufactures had convection heat value from 33 to 156 W/m²℃, and It was coincided with design assumption. 2. The amount of energy transfer was increased with the increment of the area of heat transfer, the air flow, the gap of temperature inlet & outlet the underground water and the air. 3. The heat value was 6,825W when the air flow was 6,000m³/h and the gap of temperature between inlet and outlet of the underground water was 6℃, and It dropped from 25.8℃ to 23.2℃(-2.6℃ difference). The convection heat value was 88.5W/m²℃. 4. The heat value was 2.625W when the air flow was 4,000m³/h and the gap of temperature between inlet and outlet the underground water was 2℃, and It dropped from 27℃ to 22.5℃(-4.5℃ difference). The convection heat value was 33.6W/m²℃. 5. Correlation values(R²) of the testing heat values of the trial manufacture type I, II, and III were 0.9141, 0.8935, and 0.9323 respectively, and correlation values(R²) of the amount of the air flow 6,000m³/h, 5,000m³/h, 4,000m³/h were 0.9513, 0.9414, and 0.9003 respectively.

• Cartoon and Animation Studies
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• 통권15호
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• pp.1-12
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• 2009

As the technology realizing digital multimedia has been developing remarkably based on Internet environment, today we can gain various information we need quickly and easily without regard to time or place by using world wide web. The recent spread of digital animation as a way of communication on Internet has been forming a new communication paradigm according to the development of age. Besides, digital animations embodied on web are a kind of communication medium which is expressed through interactions using different digital multimedia tools and put the concepts of time and space together. This is a form which can cope with various forms of information, and it occupies a high rate on web and is used often. Web animations offer various forms of communication, such as interface structure design for information transfer, characters, typography, and other graphic elements, which make users feel maximized real dynamics. This paper analyzes and evaluates the categories according to the characteristics, information and usage types of digital animations used on web, examines more efficient communication expressions based on them, and pays attention to the Internet environment that will develop and change in the future. With regard to it, this research aims at suggesting a useful theory so that diverse digital animations on web based on Internet environment would develop into a new communication paradigm responding to the change of time.

• Transactions of the KSME C: Technology and Education
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• 제3권4호
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• pp.241-248
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• 2015

Most of the Stirling cryocoolers used for infrared detector cooling in domestic is imported. Because the cooler has a high price, short life and poor durability, demand for the coolers continues steadily. However, the cooler is highly related to defense and space technology, technology transfer or co-development with the countries having experties in cooler design is very limited. The pulse tube cooler to be developed in this study is such that the mechanical piston in low temperature actuating part is replaced by the gas piston and linear compressor is adopted, which results in low vibration, long life and better durability. It is expected that development of the pulse tube cooler will not only improve our technology to the level of advanced countries, but also enhance the skills in designing and manufacturing of the infrared detector.

• Journal of The Korea Institute of Healthcare Architecture
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• 제21권2호
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• pp.35-43
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• 2015

Purpose: A large number of the mobility impaired have increasingly used the railway station, so the application of UD(Universal Design) on urban railway station has been interested. However, the current criteria used in domestic areas have concerned about the effective administration of railway station facilities rather than the needs of he mobility impaired. Of diverse facilities in railway station, the platform is considered as an important space due to many transportation users' riding or transfer in railway stations. Therefore, this study aims to explore the detailed criteria in adapting ideas from UD to platform within railway station. Methods: This study explores the criteria by evaluating findings from previous studies. First, all criteria related to platform in domestic and foreign areas are taken together and analyzed, and appropriate criteria first are established. Based on these, the current situation of platform facilities in railway station is evaluated. Then, the detailed criteria applicable to railway station platform are concluded, by reviewing types of the mobility impaired and principles of UD. Result: Findings from this study are as follows. First, the current criteria applied to railway station platforms lack ideas of UD, while the criteria used in foreign countries adequately reflect the ideas of UD on railway station platforms; therefore, the better criteria applicable to platform facilities in domestic railway station are necessary. Second, standard criteria used in domestic areas with newly additional criteria suggest that platform facilities should be established according to those criteria. Taken together, the better platform facilities should be provided to railway users through the application of UD to railway station platforms. Implications: For the future users in railway station platforms, the additional research on criteria of UD as well as diverse types of spaces within railway stations should have been continued.

• Archives of design research
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• 제13권3호
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• pp.123-134
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• 2000

Electronic commerce in digital environment is greatly different from the commerce in physical environment in the past (reality environment) in terms of marketing, distribution structure and, above an, comsumers'purchase pattern. The Old purchase pattern is that a consumer buys a product after s/he touches, tests, and feels it physically, while the purchase pattern in electronic commerce enables the comsumer to make a decision about whether to buy it or not through the information gleaned from the computer monitor screen. A number of products which appears in the market now are designed to use the reality environment setup without consideration of the digital environment, of which the intention is to appeal to consumers with a series of design process. However, taking under consideration the present situation in which lots of electronic commerce are made in the cyber space or digital environment, we are required to forward the product design which can gains the positive attraction for consumers in this environment. Factor analysis is made in order to understand how the subjects perceive the image of the design of the product both in reality situation and in digital environment. The result shows the first factor has different images in those environments. In the background of this conclusion rests the fact that the difference of the transfer of formative factors to consumers is made in the images which show themselves in those different environments.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제34권5호
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• pp.562-570
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• 2008

Most purulent maxillofacial infections are of odontogenic origin. Treatment of infection includes the surgical intervention, such as incision and drainage, and adjunctive treatment. The use of high-dose antibiotics is also indicated. The choice of an antibiotics should be based on the knowledge of the usual causative microbes and the results of antibacterial sensitivity test. We have undertaken clinical studies on 119 patients in Dept. of Oral and Maxillofacial Surgery, Inha University Hospital from January 2000 to December 2007. Many anaerobic microbes are killed quickly when exposed to oxygen. Thus the needle aspiration techniques and the transfer under inert gas were used when culturing. The aim of this study was to obtain informations for the bacteriologic features and the effective antimicrobial therapy against maxillofaical odontogenic infections. The obtained results were as follows: 1. The most frequent causes of infections were odontogenic (88.3%), and in odontogenic cause, pulpal infections were the most common causes(53.8%). 2. The buccal and submandibular spaces (respectively 23.5%) were the most frequent involved fascial spaces, followed by masticator spaces (14.3%). 3. The most common underlying medical problems were diabetes (17.6%), however the relation with prognosis was not discovered. 4. The complications were the expiry, mediastinitis, necrotizing fasciitis, orbital abscess, and osteomyelitis. 5. The most common admission periods were 1-2 weeks, and the most patients were discharged within 3 weeks. However, patients who admitted over 5 weeks were about 10%. 6. A total of 99 bacterial strains (1.1 strains per abscess) was isolated from 93 patients (78.2%). The most common bacterium isolated was Streptococcus viridans (46.2%), followed by $\beta$-hemolytic group streptococcus (10.1%). 7. Penicillins (penicillin G 58.3%, oxacillin 80.0%, ampicillin 80.0%) have slightly lower sensitivity. Thus we recommend the antibiotics, such as glycopeptides (teicoplanin 100%, vancomycin 100%) and quinolones (ciprofloxacin 90.0%) which have high susceptibility in cases in which peni cillin therapy failed or severe infections.

• Journal of Bio-Environment Control
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• 제20권2호
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• pp.78-82
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• 2011

Ventilation rates, inside and outside weather data were measured in a arch-shape single-span plastic greenhouse growing tomatoes. On the roof of the experimental greenhouse, round windows which have a diameter of 0.6 m were installed at intervals of 8m. It showed that the number of air changes in this greenhouse were average 0.17 volumes per minute and in the range of 0.02 to 0.32 volumes per minute. These air changes are insufficient to meet the recommended ventilation rate for commercial greenhouses, and it is estimated that interval of 6 m is appropriate for spring or fall season. For summer season, it is necessary to narrow the space or to enlarge the open area of roof windows. Using the heat balance model, the evapotranspiration coefficients of greenhouse tomatoes were estimated from experimental ventilation data, overall heat transfer and solar radiation. It showed that the evapotranspiration coefficients were average 0.62 and in the 0.39 to 0.85 range. We suggest applying 0.6 as the evapotranspiration coefficient in design of ventilation for the single-span tomato greenhouses.

• Archives of design research
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• 제15권4호
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• pp.1-14
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• 2002

In the past, companies concentrated their efforts on developing new technologies and producing new products. But new technologies in this information age do not make difference any more comparing to other companies. In this marketing environment, a company must appeal strongly their own image to the customers' brains to make better difference than other companies do. One of the best way to make their own image in the customer's brains might be outgrowing themselves of the one-way communication such as the printed-media or broadcast-media and preparing some space such as advertisement halls or pavilions where customers and companies meet each other and make mutual communications between both of them. Therefore, we need to study systematically on the design elements in the advertisement halls or pavilions. To begin with, we should lully understand the basic idea by looking up the reference literature. We case-studied on the basic of constructive elements of advertise halls of both SAMSUNG and LG Electronics Co. The purpose of this study is to realize that we can transfer effectively the company's image to the customers only if we fully understand company's business philosophy and vision in advance to start design the advertisement hails. We should also realize that it is also important to manage systematically the company's design strategic elements' to achieve its changing goals in more logical and scientifically way.