• Journal of the Society of Naval Architects of Korea
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• v.60 no.1
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• pp.38-47
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• 2023

According to the government policy of environmental regulations, interest of ship, which made with High-Density Polyethylene (HDPE) as a low-carbon and eco-friendly material, is growing as a substitute for the existing fishery boat hull materials such as FRP, aluminum, steel etc. However, regulations related to the production of HDPE ship are still quite incomplete. Even there are no regulations related to structural analysis. Therefore, in this study, structural analysis is carried out by applying different design loads for each international classification for 38ft class HDPE power boats, and the results are compared and analyzed. According to this study, although there is a correlation between the based pressure value and the analysis result value of each class regulation, it is not necessarily proportional. Also, This analysis result shows a difference not only depending on the size of design load, but also application range of the load, the pressure adjustment factor and section shape. However, the occurrence point and trend of the maximum stress values were quite consistent. It is hoped that the results of this study will be used when establishing HDPE ship structure analysis procedures and standards in the future.

• International conference on construction engineering and project management
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• 2011.02a
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• pp.66-73
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• 2011

With rapid industrialization, electric power consumption has been increasing every year in Korea and in other countries. The provision of additional power stations to produce more electricity is one possible response to this steady increase in consumption. Another alternative is to improve the efficiency of existing stations through timely and effective maintenance works. Since the construction of a new power plant involves a large amount of capital as well as difficulties in the selection of sites, the improvement of existing power stations' efficiencies is often a preferred solution. Therefore, this paper focuses on maintenance project management to address this issue. Among several types of maintenance works, this paper concentrates on planned outage maintenance (POM). This focus arises from the critical impact of POM on other maintenance work, as well as the entire process of electricity production. Unlike other maintenance work, POM is done on the basis of mid and long-term plans. In addition, only POM works are conducted during the outage of all power plants. To evaluate the efficiency of POM works, budget data relating to 164 POM projects between 2001 and 2008 was collected from 7 sites in South Korea. Data envelopment analysis (DEA) was selected as a methodology for evaluation. From this analysis, comparative study was used to determine the categories of projects that had performed well, and those with the most optimized budget structures. Moreover, through discussion with industry, this research develops a feasible proposed method by which to enhance the efficiency of POM projects.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.1-11
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• 2007

Light is an environmental component inevitably regulating photosynthesis and photo-morphogenesis, which are involved in the plant growth and development. Studies were conducted at the International Rice Research Institute, Philippines in 2004 and 2005, with aims to investigate 1) morphological responses of rice plants to low radiation, 2) morphological alteration of shade-grown plants when exposed to high light intensity, and 3) photosynthetic responses of shade-grown rice plants. Reduction in solar radiation by 40% induced increases in the area on a single leaf basis, biomass partitioning to leaves, and chlorophyll meter readings but brought about retardation of tiller development and decrease in above-ground biomass production of rice varieties. When the shade-grown plants from two weeks of transplanting to panicle initiation were exposed to full solar radiation after panicle initiation, they demonstrated less increase in chlorophyll meter readings and more decrease in leaf nitrogen concentrations from panicle initiation to flowering than control plants that were grown under the ambient solar radiation for whole growth period after transplanting. Shade-grown rice plants exhibited lower carbon assimilation rates but higher internal $CO_2$ concentrations on a single leaf basis than control plants, when measurements for shade-grown rice plants were made under the shading treatments. But when the measurements for shade-grown plants were made under the full solar radiation, light-saturated carbon assimilation rates were similar to control plants. Response of photosynthetic rates to varying light intensities was not considerably different between shading treatments and control. Yield reduction was observed in the shading treatments from panicle initiation to flowering and from flowering to physiological maturity, mainly by less spikelets per panicle and poor grain filling, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.7
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• pp.1054-1060
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• 2017

Objective: This study was aimed at evaluating effects of cattle breed resources and alternative mixed-feeding practices on meat productivity and emission intensities from household farming systems (HFS) in Daklak Province, Vietnam. Methods: Records from Local $Yellow{\time}Red$ Sindhi (Bos indicus; Lai Sind) and 1/2 Limousin, 1/2 Drought Master, and 1/2 Red Angus cattle during the growth (0 to 21 months) and fattening (22 to 25 months) periods were used to better understand variations on meat productivity and enteric methane emissions. Parameters were determined by the ruminant model. Four scenarios were developed: (HFS1) grazing from birth to slaughter on native grasses for approximately 10 h plus 1.5 kg dry matter/d (0.8% live weight [LW]) of a mixture of guinea grass (19%), cassava (43%) powder, cotton (23%) seed, and rice (15%) straw; (HFS2) growth period fed with elephant grass (1% of LW) plus supplementation (1.5% of LW) of rice bran (36%), maize (33%), and cassava (31%) meals; and HFS3 and HFS4 computed elephant grass, but concentrate supplementation reaching 2% and 1% of LW, respectively. Results: Results show that compared to HFS1, emissions ($72.3{\pm}0.96kg\;CH_4/animal/life$; least squares $means{\pm}standard$ error of the mean) were 15%, 6%, and 23% lower (p<0.01) for the HFS2, HFS3, and HFS4, respectively. The predicted methane efficiencies ($CO_2eq$) per kg of LW at slaughter ($4.3{\pm}0.15$), carcass weight ($8.8{\pm}0.25kg$) and kg of edible protein ($44.1{\pm}1.29$) were also lower (p<0.05) in the HFS4. In particular, irrespective of the HSF, feed supply and ratio changes had a more positive impact on emission intensities when crossbred 1/2 Red Angus cattle were fed than in their crossbred counterparts. Conclusion: Modest improvements on feeding practices and integrated modelling frameworks may offer potential trade-offs to respond to climate change in Vietnam.

• Journal of International Area Studies (JIAS)
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• v.14 no.4
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• pp.27-52
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• 2011

The regions of Central Asia have each acquired an elevated strategic importance in the new security paradigm of post-September 1lth. Comprised of five states, Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan, Central Asia's newly enhanced strategic importance stems from several other factors, ranging from trans-national threats posed by Islamic extremism, drug production and trafficking, to the geopolitical threats inherent in the region's location as a crossroads between Russia, Southwest Asia and China. Although the U.S. military presence in the region began before September 11th, the region became an important platform for the projection of U.S. military power against the Taliban in neighboring Afghanistan. The analysis goes on to warn that 'with US troops already in place to varying extents in Central Asian states, it becomes particularly important to understand the faultlines, geography, and other challenges this part of the world presents'. The Kyrgyz military remains an embryonic force with a weak chain of command, the ground force built to Cold War standards, and an almost total lack of air capabilities. Training, discipline and desertion - at over 10 per cent, the highest among the Central Asian republics - continue to present major problems for the creation of combat-effective armed forces. Kyrgyzstan has a declared policy of national defence and independence without the use of non-conventional weapons. Kyrgyzstan participates in the regional security structures, such as the Collective Security Treaty Organisation (CSTO) and the Shanghai Co-operation Organisation (SCO) but, in security matters at least, it is dependent upon Russian support. The armed forces are poorly trained and ill-equipped to fulfil an effective counter-insurgency or counter-terrorist role. The task of rebuilding is much bigger, and so are the stakes - the integrity and sovereignty of the Kyrgyz state. Only democratization, the fight against corruption, reforms in the military and educational sectors and strategic initiatives promoting internal economic integration and national cohesion hold the key to Kyrgyzstan's lasting future

• Journal of the Korean Society of International Agriculture
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• v.23 no.5
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• pp.552-559
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• 2011

China is a one of the largest agricultural countries in the world. China consumes around 12.5 billion kilograms of seeds each year. Suchhuge demand for seeds has made the Chinese seed market more and more attractive for investment. Through analysis on the present situation and existing problems of the seed industry in China and based on the current Chinese seed industry development, some future prospects for investments are indicated. This investigation was carried out to propose the appropriate strategies on the development of the Korea seed industry as it considers its entry into the China seed market as a new growth engine in the agricultural sector. The basic law regulating the Chinese seed industry is the PRC Seed Law that generally refers to the protection of germplasm resources, verification of varieties, seed quality issues, the import and export of seeds, seed administrative management, and various rights and obligations. The regulations were aimed at the protection of the rights concerning new varieties of plants. China has two main industry associations, the National Seed Association and the China Seed Industry IP Union, that are non-profit associations consisting of entities and people engaging in the seed scientific research, production, operation and management. The China National Seed Group Co., Ltd. ("Sino Seeds") is the market leader in China regarding the seed industry. The chinese government, however, encourages investment from multinational companies as well as importation of modern crop planting management technologies and equipment. It supports the entry of investors with proven experiences in breeding and germplasm resources expansion and R&D. There has never been a better time for multinational companies with proven seed industry experience to look at building relationships with the Chinese government and enterprises.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.744-756
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• 2018

The purpose of this study was to investigate the anti-inflammatory effect and the antimicrobial activity to skin flora of essential oil from rosemary that naturally grown in Jeju. rosemary essential oil was extracted by water distillation essential oil extraction method. In order to confirm the anti-inflammatory activity of rosemary essential oil, it was confirmed that the production of NO and $PGE_2$ induced by LPS in RAW 264.7 cells was inhibited in a concentration-dependent manner. Western blot analysis showed that the expression of iNOS and COX-2, which are biosynthetic enzymes, decreased in a concentration-dependent manner. In addition, production of $TNF-{\alpha}$ and IL-6 the pro-inflammatory cytokines were inhibited. Antimicrobial activities of three S. epidermidis and three P. acnes strains including two antibiotic resistant strains were observed in paper disc method and MIC and MBC tests showed inhibition of bacterial growth and death. From the results of the experiment, we confirmed that rosemary essential oil has the anti-inflammatory and antimicrobial efficacy and it could be used as a cosmetic and skin care material in the future.

• Journal of Environmental Science International
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• v.26 no.2
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• pp.231-238
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• 2017

Rapid industrial development has led to a serious problem of pollution in the industrial sector. With the increasing social need for environmental protection, research on air pollution prevention equipment for reducing pollutants in industrial processes is actively being undertaken. The deterioration of existent, installed facilities, their increased emission rates, and the strengthening of the effluent quality standards make complying with permissible emission standards difficult. In fact, installing new electric precipitators or complementing existent facilities is inevitable. The expansion and complementation of the installed electrical precipitators have led to improvements in dust collection efficiency, shorter working times, and lower costs. Because of its easy installation and simple manufacturing process, the production method with the discharge electrode of an electric precipitator is widely used. The following conclusions were reached by classifying discharge electrodes into four types based on the production method and mutually comparing them by their dust collection efficiency. None of the four types used in this study were damaged by impact. However, we were able to confirm some strain from the compression sites of both type A and type B. Both type B and type C are expected to have greater dust collection efficiencies than the other models due to their large vibration transmissibility. Moreover, the high vibrational energy is expected to cause rapping damage during its operation. Particularly, in the case of type B, some of the strain was found at the end of the compression site. The coupling schemes of both type C and type D are out of vibration transmissibility. On the other hand, the ability to maintain straightness and solidity of the side is regarded as outstanding and stable. Type D has outstanding on-site workability, considering the presence of locking, structural stability, and work conditions. From these experiments, we determined that type C is the most ideal connection method of discharge electrode, considering its construction period of renovation. Type C is inferior to type D with regard to on-site workability. However, type C has outstanding dedusting transmission with regard to the straightness, solidity maintenance, and vibration of shearing stress.

• Journal of Animal Science and Technology
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• v.44 no.5
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• pp.541-548
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• 2002

This study, consisting of two experiments, was conducted to determine the effects of feeding heat treated protein and mineral complex (HPM) on milk production and composition, and ruminal fermentation of Holstein dairy cows. In in vitro experiment, HPM levels were 0, 0.2, 1 and 2%, and Timothy hay, which was substrate, was milled as 1 mm size, and the effects of HPM on pH, ammonia and VFA were analyzed after incubation times of 0, 6, 12, 24 and 48 h, respectively. The pH and ammonia production were not significantly different between treatments during the incubation. In addition, generally, total VFA and individual VFA were not affected by HPM on 0, 6 and 24 h. While, total VFA and individual VFA were increased in 0.2% and 1% of HPM supplemented treatments, but decreased in 2% of HPM treatment compared with control on 12 h. On 48 h, total VFA and individual VFA were increased in HPM treatments compared to control (P<0.05). However, A/P ratio was not affected by HPM supplementation. Gas production was higher in HPM treatment compared to control on 24 h (P<0.05) and 48 h (P<0.05). In lactating experiment, fourteen lactating Holstein cows were used for 4 months in a cross over experimental design. There were two treatments; no added HPM as a control and 0.2% of HPM added as a test treatment. Daily milk yield (P<0.001), 4% FCM (P<0.001), milk protein (P<0.05) and SNF (solid not fat; P<0.05) were increased in HPM treatment compared to control. While, milk fat, MUN (milk urea nitrogen) and SCC (somatic cell count) were not significantly different between treatments.

• Environmental and Resource Economics Review
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• v.32 no.1
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• pp.47-75
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• 2023

Compared to the EU, which legislates the Carbon Border Adjustment System (CBAM), the United States' carbon border adjustment policy movement is still relatively slow. Recently, however, a related bill has been proposed in the United States, and research institutes have been presenting research results on how to introduce an upstream carbon tax rather than an emission trading system and carry out carbon border adjustment based on it. Therefore, in this study, we looked at the economic and environmental effects of introducing this type of upstream carbon tax and carbon border adjustment in Korea. If an upstream carbon tax of KRW 30,000 per ton of CO₂ is applied to the net supply of domestic fossil energy, the expected carbon tax revenue is approximately KRW 22.9961 trillion, equivalent to about 5.7% of the total revenue of the Korean government of KRW 402 trillion in 2019. In addition, the carbon dioxide content of the steel sector, calculated based on the energy supply and demand status of the steel sector, which emits the most greenhouse gas emissions in Korea and has a considerable amount of overseas exports, was 106.22 million tons of CO₂. On the other hand, assuming that the upstream carbon tax of 30,000 won per ton of CO₂ embodied is directly passed on to the production cost of the steel sector, the carbon tax burden in the steel sector is estimated to reach approximately KRW 3.1865 trillion. Even after deducting KRW 1.1599 trillion in export refunds estimated by using the share of exports of steel products, the net carbon tax burden on steel products for domestic demand amounts to KRW 2.0266 trillion, which is analyzed to act as a factor in increasing the price of steel products.