• Journal of Energy Engineering
• /
• v.26 no.2
• /
• pp.99-120
• /
• 2017

In SS branch of Korea District Heating Corporation, Combined Heat & Power power plant with 99MW capacity and 98Gcal / h capacity is operated as a district electricity business. In this region, it is difficult to operate the generator due to the problem of surplus heat treatment between June and September due to the economic recession and the decrease in demand, so it is urgent to develop an economical energy new business model. In this study, we will develop an optimized operation model by introducing a renewable energy hybrid system based on actual operation data of this site. In particular, among renewable energy sources, fuel cell (Fuel Cell) power generation which can generate heat and electricity at the same time with limited location constraints, photovoltaic power generation which is representative renewable energy, ESS (Energy Storage System). HOMER (Hybrid Optimization of Multiple Energy Resources) program was used to select the optimal model. As a result of the economic analysis, 99MW CHP combined cycle power generation is the most economical in terms of net present cost (NPC), but 99MW CHP in terms of carbon emission trading and renewable energy certificate And 5MW fuel cells, and 521kW of solar power to supply electricity and heat than the supply of electricity and heat by 99MW CHP cogeneration power, it was shown that it is economically up to 247.5 billion won. we confirmed the results of the improvement of the zone electricity business condition by introducing the fuel cell and the renewable energy hybrid system as the optimization process model.

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.13 no.4
• /
• pp.305-312
• /
• 2010

Seagrass beds are a type of coastal wetland with many ecosystem services and precious economic values. Seagrass meadows used to be widespread along the coasts in northern Chinese seas, yet they have long been overlooked and lack devoted study on their history and status. This paper firstly reveals, by synthesis of information on composition of seagrass species and their distribution, that the seagrasses in this region have experienced considerable declines, both in terms of distribution and biomass, from the earliest record to present days. Then, a case study at the seagrass bed of Chudao is described to show the status of representative seagrass meadows. The results indicate that the environmental condition is good, seagrasses are in recovery, the planktoners are healthy and rich fishery resources and the mammal finless porpoise are associated with the seagrass bed. The cause(s) of historical seagrass decline and current conditions are also discussed, and future recommendations on seagrass protection and mapping are suggested.

• Food Science and Preservation
• /
• v.18 no.2
• /
• pp.184-190
• /
• 2011

Limonoid UDP-glucosyltransferase (LUGT) is an enzyme that converts limonoids into their corresponding glucosides and ultimately ameliorates limonoid bitterness in Citrus species. In this paper, the LUGT gene was cloned via PCR from 10 Jeju Citrus species. All the deduced glucosyltransferase proteins harbored a highly conserved plant secondary product glucosyltransferase (PSPG) motif within the C terminal region. Phylogenetic analysis based on the amino acid sequence comparison of the LUGT proteins from 10 Citrus species generated three distinct types. The expression patterns of LUGT gene in three representative species from each type were quite different with that of C. unshiu Marc. cv. Miyagawawase(Gungcheon), which his without distinctive juice delayed bitterness. Ourresultssho wth at some Citrus speciessuchas Citrusleiocarpa HORT(Bingul), Citruserythrosa HORT (Dongjunggul), and Citrustachibana TANAKA(Honggul) end emicin Jeju maybe susceptible to intense juice delayed bitterness due to delay inexpression of LUGT.

• Journal of the Economic Geographical Society of Korea
• /
• v.15 no.4
• /
• pp.550-569
• /
• 2012

This paper studies the R&D network of the Zhongguancun Cluster, the most representative innovative cluster of the high-tech industry in China at present. For this study, Zhongguancun Cluster was the first high-tech cluster to have been created in China, the current Zhongguancun Cluster has played a leading role in the development of the high-tech industry in China. In addition, the Zhongguancun Cluster has at helped elevate China as a key region in terms of research development in relation to the high-tech industry. In particular, companies evaluate the research development network culture of Zhongguancun cluster positively and this increases their tendency to approach the research development network with an open mind. The main contents in research development network are as follows; (1) joint or consigned research development and technology transfer in the case of research development network between companies, (2) joint or consigned research development, human resource support and employment, technical advice and consultant and technology transfer in the case of industrial-educational relationships (3) joint or consigned research development, technical advice and consultant and technology transfer in the case of industrial-research relationships, (4) financial support and participation in joint research development project held by government in the case of industrial and governmental relationships (5) financing for research development, utilization of research human resources, purchase of research development and use of research development equipment for mediators. The main difficulties in creating a research development network are 'lack of mutual trust', 'financial problems of companies' and 'lack of information'. Especially, the main key obstacles for the most important research development network between industry and government in the case of the Zhongguancun Cluster are 'complicated and strict procedures. Therefore, more accurate and detailed understanding of the conditions and the following institutional measures from government are required for research development among companies.

• Journal of the Korea Concrete Institute
• /
• v.14 no.6
• /
• pp.851-863
• /
• 2002

Corrosion products of reinforcement in concrete induce pressure to the adjacent concrete due to the expansion of steel. This expansion causes tensile stresses around the reinforcing bar and eventually induces cracking through the concrete cover The cracking of concrete cover will adversely affect the safety as well as the service life of concrete structures. The purpose of the this study is to examine the critical corrosion amount which causes the cracking of concrete cover. To this end, a comprehensive experimental and theoretical study has been conducted. Major test variables include concrete strength and cover thickness. The strains at the surface of concrete cover have been measured according to the amount of steel corrosion. The corrosion products which penetrate into the pores and cracks around the steel bar have been considered in the calculation of expansive pressure due to steel corrosion. The present study indicates that the critical amount of corrosion, which causes the initiation of cracking, increases with an increase of compressive strength. A realistic relation between the expansive pressure and average strain of corrosion product layer in the corrosion region has been derived and the representative stiffness of corrosion layer was determined. A concept of pressure-free strain of corrosion product layer was introduced to explain the relation between the expansive pressure and corrosion strain. The proposed theory agrees well with experimental data and may be a good base for the realistic durability design of concrete structures.

• Journal of Korean Society of Forest Science
• /
• v.101 no.2
• /
• pp.244-250
• /
• 2012

The objective of this study was to analyze the above-ground biomass and crown fuel characteristics of Pinus densiflora stands in Yangyang, Gangwon province. A total of thirteen representative trees were destructively sampled in Yangyang region. The results showed that the stem density ($g{\cdot}cm^{-3}$) was 0.347~0.409, whereas the above-ground biomass expansion factors ranged from 1.251~1.419. In terms of crown fuel biomass, the above-ground biomass was $161.6Mg{\cdot}ha^{-1}$ while the stem biomass, branch biomass and needle biomass were $126.4Mg{\cdot}ha^{-1}$, $29.3Mg{\cdot}ha^{-1}$ and $5.9Mg{\cdot}ha^{-1}$, respectively. Needles and twigs with less than 1 cm diameter accounted 45.2% of the total crown fuel load. The available crown bulk density, which was calculated by dividing the crown fuel load to the crown volume, was $0.178kg{\cdot}m^{-3}$. The results of this study on the biomass and carbon stocks estimation of the Pinus densiflora together with the crown fire hazard assessment based on crown fuel loads are very significant information for the forest managers.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.31 no.6
• /
• pp.461-468
• /
• 2009

Purpose: Platelet derived growth factor(PDGF)-BB and bone morphogenetic protein(BMP)-2 are well-known representative growth factors. The purposes of this study were to investigate the effect of rhPDGFBB and rhBMP-2 on osseointegration of titanium implants at periimplant bone defects grafted with hydroxyapatite and to evaluate the feasibility of imaging bone structures around screw-type titanium implant with micro-CT. Materials and Methods: The first molar and all premolars in the mandible region of four beagle dogs were extracted. Following a healing period of 4 months, three $8{\times}8{\times}6mm$-sized bony defects were formed and screw-type titanium implants were placed with hydroxyapatite(HA) block and growth factors; Control group, PDGF group and BMP group. Two months post-implantation, the mandible was harvested. Bone volume(BV), bone-to-implant contact(BIC) and bone mineral density(BMD) were analyzed with micro-CT and histology. Results: According to micro-CT analysis, BV and BMD measures of PDGF and BMP group were significantly higher than control group(BV; PDGF group: $p{\fallingdotseq}0.011$, BMP group: $p{\fallingdotseq}0.006$/BMD; PDGF group: $p{\fallingdotseq}0.020$, BMP group: $p{\fallingdotseq}0.011$) and BIC measures of BMP group were significantly higher than PDGF group($p{\fallingdotseq}0.015$). In histologic evaluation, BIC measures of BMP group was significantly higher than PDGF group($p{\fallingdotseq}0.048$). The values of BV in histologic sections were higher than in micro-CT images and the values of BIC in micro-CT images were higher than in histologic sections. Conclusion: The findings of this experimental study indicates that the use of rhPDGF-BB and rhBMP-2 can increase new bone formation in a large bony defect around titanium implant, and rhBMP-2 is more effective than rhPDGF-BB. Micro-CT can be considered useful for assessment as a rapid and nondestructive method for 3-dimensional measurement of bone healing around implants. Further study is necessary, however, to remove metal artifacts around titanium implant and to standardize the method.

• Journal of architectural history
• /
• v.18 no.2
• /
• pp.47-63
• /
• 2009

This study focused on changes in form and spatial uses of Urban Hanok in Bukchon, Seoul. There are 10 representative cases which have been renovated through the policy of 'Preservation & Regeneration of Bukchon' by Seoul metropolitan government and other experts. Changes in form and spatial uses of Urban Hanok in Buckon are as follows. First, Changes of scale. Trough removing extension parts, facade of renovated Hanoks are 'transformed' into recovering their identity. Using basements or lofts, intensive application of spaces is transformation which promotes the vitality of Hanoks. Second, changes of space organization. As Hanok changes its function from residence to commercial or cultural use, il a1so changes space character or reorganizes space organization. It is important that deciding function of Hanok has to adjust its scale and organization. Third, changes of construction performance. Through introducing new material and constructing method, performance of wall has been changed respecting its wooden structure and interior-exterior figure. However, technical studies must back it up not to destroy its value of eco-friendly architecture. Fourth, changes of facility systems, like floor heating system. They changes floor level of Hanok equally, and then sections of Hanok have became simple. Furthermore, inserting new facility space, such as boiler room, stand-up kitchen, bathroom and toilet, organization of space also changed. It is necessary that wise alternative proposal through the method of transformation or mutation must be presented. These four changes can be classification into method of 'transformation' and 'mutation'. Changes of scale are method of transformation and changes of space organization are method of mutation. Also, while changes of construction performance are mutation, changes of facility systems are transformation. Recently, as price of lots have been increased, a lot of Hanoks have been commercialized. Thc commercial energy threat 'the identity of Bukchon as residential area'. From now on, to operate 'identity' and 'vitality' complementary, it is necessary to make up for the preservation policy of Hanok and consolidate renovating standards of Hanok which correspond to character of particular region and building usage.

• Journal of the Korean Geographical Society
• /
• v.47 no.2
• /
• pp.208-225
• /
• 2012

The spatial characteristics of changes in extreme temperature indices for 2070-2099 relative to 1971-2000 in the Republic of Korea were investigated using daily maximum (Tmax) and minimum (Tmin) temperature data from a regional climate model (HadGEM3-RA) based on the IPCC RCP4.5/8.5 at 12.5km grid spacing and observations. Six temperature-based indices were selected to consider the frequency and intensity of extreme temperature events. For validation during the reference period (1971-2000), the simulated Tmax and Tmin distributions reasonably reproduce annual and seasonal characteristics not only for the relative probability but also the variation range. In the future (2070-2099), the occurrence of summer days (SD) and tropical nights (TR) is projected to be more frequent in the entire region while the occurrence of ice days (ID) and frost days (FD) is likely to decrease. The increase of averaged Tmax above 95th percentile (TX95) and Tmin below 5th percentile (TN5) is also projected. These changes are more pronounced under RCP8.5 scenario than RCP4.5. The changes in extreme temperature indices except for FD show significant correlations with altitude, and the changes in ID, TR, and TN5 also show significant correlations with latitude. The mountainous regions are projected to be more influenced by an increase of low extreme temperature than low altitude while the southern coast is likely to be more influenced by an increase of tropical nights.

• The Journal of Korean Medical History
• /
• v.31 no.1
• /
• pp.123-134
• /
• 2018

Today, knowledge itself has become a resource which must be protected by the pertinent community of its contributors and users, from being manipulated or distorted by third-party players. The preservation of knowledge in relationship to the cultural context of its origins, has been recognized by international organizations intent on maintaining authentic voice and perspective. Globally, the WIPO (World Intellectual Property Organization) organizes the annual IGC (Intergovernmental Committee) meeting to address various issues associated with each country's utilization of intellectual and bio source property. Korean Medicine is the official name for the traditional medicine that has been inherited from the cultures of the Korean Peninsula. It is one of the four practices of East Asian Medicine including Traditional Chinese Medicine (TCM) from China, Kampo Medicine of Japan, and Sino-Vietnamese Medicine in Vietnam. As a cultural treasure representing centuries of evolving knowledge, Korean Medicine is protected under intellectual property rights afforded by WIPO, and must be understood in relationship to, and distinct from, TCM. It is understood that China has a strong political purpose to claim all the traditional medicines of the East Asian region under the name of TCM, including Korean Medicine. In fact TCM was authorized as the representative name for all East Asian medicine by decisions made by the ISO (International Standard Organization) in 2015. This paper proposes a pilot study on how to protect the intellectual property of Korean Medicine from efforts by China to claim it under the umbrella of TCM. Using the Uibang Yuchui (醫方類聚, Classified Collection of Medical Formulas) this paper suggests establishing a Database of UBYC, which was published in 1477 by the Joseon Korea government. UBYC was the reorganized version of contemporary East Asian medical sources, and has already hundreds of year's rich indigenous and culturally specific medical history of Korea, from which Korean Medicine has been built.