• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.797-800
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• 2002

Instead of a solution process producing amorphous $LiV_3O_8$ form, we prepared Lithium vanadate glass by melting $Li_2O-P_2O_5-V_2O_5$ and $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$ composition in pt. crucible and by quenching on the copper plate. From the crystallization of $Li_2O-P_2O_5-V_2O_5$ and $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$, we could abtain glass-ceramics having crystal phase, LiV3O8 from glass matrix. The material heat-treated at lower-temperature, $250^{\circ}C$ had less crystalline and lower capacity, But the material heat-treadted at higher-temperature, $330^{\circ}C$ had higher capacity and $Li_2O-P_2O_5-V_2O_5$ glass-ceramics had higher capacity than $Li_2O-P_2O_5-Bi_2O_3-V_2O_5$ glass-ceramics.

• 한국안전학회지
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• 제25권2호
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• pp.41-46
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• 2010

This is to show some basic data for introducing both circulated aggregate and recycled powder producing waste concrete. Standard-mixing design for 24MPa has been basically used and added and replaced normal aggregate with recycled powder made of waste concrete. In addition, polycarboxylate high-range water reducing agent has been used because recycled powder is missing adhesive strength and it is not compare with cement's adhesive strength. Compressive strength with powder mixture of 2%, 4%, 6%, 8%, and 10% has been decreased down to 80% of normal concrete material strength without recycled powder mixture. This result has same decreasing proportion to tensile strength of the material. Resistant capacity change of beam varying with recycled powder mixture has been decreased down to 60% of normal concrete bean capacity, while there are 80% decrease of material strength. But strength and capacity change has same consistent decrease ratio. It is found that recycled powder with approximately 15% unit concrete volume can be replaced with cement in reasonable admixture mixing condition.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.587-594
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• 2023

This study investigates the impacts of nuclear energy consumption on environmental quality from a different perspective by focusing on carbon dioxide (CO2) emissions, ecological footprint, and load capacity factor. In this context, the South Korea case, which is a leading country producing and consuming nuclear energy, is investigated by considering also economic growth, and the 1997 Asian crisis from 1977 to 2018. To this end, the study employs the autoregressive distributed lag (ARDL) approach. Different from previous literature, this study proposes a load capacity curve (LCC) and tests the LCC and environmental Kuznets curve (EKC) hypotheses simultaneously. The analysis results reveal that (i) the LCC and EKC hypotheses are valid in South Korea; (ii) nuclear energy has an improving effect on the environmental quality; (iii) renewable energy does not have a significant long-term impact on the environment; (iv) the 1997 Asian crisis had an increasing effect on the load capacity factor; (v) South Korea has not yet reached the turning point, identified as $55,411, where per capita income improves environmental quality. Overall, the results show the validity of the LCC and EKC hypotheses and prove the positive contribution of nuclear energy to South Korea's green development strategies.

• 한국축산시설환경학회지
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• 제3권1호
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• pp.49-56
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• 1997

Most of Korean broiler farms are constructed with vinyl houses. Such types of broiler farms might be cheaper in terms of cost, but poor in terms of environment condition. According to enlargement of broiler farm size, high value production systems or automatic facilities are introduced in this field. However, investment may not always guarantee the profit of the management. Therefore, it is necessary to undertake the investment analysis before decision making for the investment. Under the assumption that 870 Pyoung(≒$3.3㎡) of a broiler farm within 1,740 Pyoung(≒3.3㎡) of land is built with the producing capacity of 50,000 heads of chicken in a time. The total investment is calculated to be 600 million won(1,000 won≒$1.1), and out of them 58.1% is provided by the owner, 31.6% from the government loan, 5.8% from government subsidy, and 5.3% from other agencies or banks. The expected profit of the broiler farm is 64.6 million won(1,000 won≒$1.1) per year. The IRR calculated is 0.0808 which means that the rate to profit of this project would be 8.1%. This also means that for this investment the interest rate of the capital provided should be less than 8.1% per year. Considering that the current opportunity cost of the own capital is 8.5% this project is not so attractive for those who is going to build broiler farms mainly with their own capital. In other words this project would not be profitable, unless the average interest rate of the loans provided for this project is less than 8.1% per year.

• Journal of Animal Science and Technology
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• 제66권4호
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• pp.645-662
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• 2024

Climate change, driven by the natural process of global warming, is a worldwide issue of significant concern because of its adverse effects on livestock output. The increasing trend of environmental temperature surging has drastically affected meat production and meat product quality, hence result in economic losses for the worldwide livestock business. Due to the increasing greenhouse gas emissions, the situation would get prolonged, and heat exposure-related stress is expected to worsen. Heat exposure causes metabolic and physiological disruptions in livestock. Ruminants and monogastric animals are very sensitive to heat stress due to their rate of metabolism, development, and higher production levels. Before slaughter, intense hot weather triggers muscle glycogen breakdown, producing pale, mushy, and exudative meat with less water-holding capacity. Animals exposed to prolonged high temperatures experience a decrease in their muscle glycogen reserves, producing dry, dark, and complex meat with elevated final pH and increased water-holding capacity. Furthermore, heat stress also causes oxidative stresses, especially secondary metabolites from lipid oxidation, severely affects the functionality of proteins, oxidation of proteins, decreasing shelf life, and food safety by promoting exfoliation and bacterial growth. Addressing the heat-related issues to retain the sustainability of the meat sector is an essential task that deserves an inclusive and comprehensive approach. Considering the intensity of the heat stress effects, this review has been designed primarily to examine the consequences of hot environment temperatures and related stresses on the quality and safety of meat and secondarily focus on cutting edge technology to reduce or alleviate the situational impact.

• 농촌계획
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• 제22권4호
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• pp.131-138
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• 2016

Recently, the cultivated area is reduced, the ratio of upland-field in the total cultivated area is increasing relative appeared in 36.2% in 1990 from 43.7% in 2013. If upland-field can be applied well designed-infrastructure, good income crop production is possible, however, maintenance of infrastructure and a significant portion of the upland-field is maintained under insufficient infrastructure. While imports of agricultural products expanded since the 2000s in progress, looking at the self-sufficiency of upland-field crops, it is reduced to from 90% to 42% for the pepper, it is from 90% to 74% for the garlic, cereals is reduced from 42% by 26%. As a result of these conditions, the competitiveness of farmers has weakened, the risk to meet the challenges of this area of production and supply reduction increased. This study was the first to conduct a basic evaluation index, data analysis and evaluation of indicators to diagnose the agricultural production capacity of the upland field. 12 kinds classified index of producing conditions from the natural environment and eight factors for the cultivation and production capabilities have developed for the assessment of productivity of upland-field (especially Kimchi cabbage). Through this regional imbalance was found, based on the production capabilities conditions are good in Haenam, Gangneung, Pyeongchang. 3 Regions have been low and the lowest Youngwol to 0.8992. Climate(Cultivation conditions) indicators of Mungyeong region is the highest, relatively low areas were in Taebaek. In particular, it is determined to be preferred that the area required for the enhancing the production environment based on providing the convenience for the producing and maintenance of the first production area. It is necessary Increasing part of mechanization, agro-industrial competitiveness through aggressive management plans for facilities as required in the process of post-harvest storage, processing, distribution line can be improved.

• 신재생에너지
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• 제20권1호
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• pp.135-144
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• 2024

The present study investigated waste medium from a domestic shiitake mushroom farm, which was pyrolyzed to produce biochar. The yield rate of the biochar was compared after exposure to various pyrolysis temperature conditions, and the characteristics of the produced biochar were analyzed. The present study focused on the carbon dioxide (CO₂) adsorption capacity of the resulting biochar. The CO₂ adsorption capacity exhibited a correlation with the pyrolysis temperature of the biochar, with increasing temperatures resulting in higher CO₂ adsorption capacities. Brunauer-Emmett-Teller (BET) analysis showed that the CO₂ adsorption capacity was related to the surface area and pore volume of the biochar. Calcium is added to the process of producing mushroom medium. Experiments were performed to investigate the CO₂ adsorption capacity of the biochar from the waste medium with the addition of calcium. In addition, CO₂ adsorption experiments were conducted after the pyrolysis of kenaf biochar with the addition of calcium. The results of these experiments show that calcium affected the CO₂ adsorption capacity.

• 약학회지
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• 제39권6호
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• pp.585-592
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• 1995

Soil microorganisms producing immunomoduators that can restore ultraviolet B (UVB) radiation-induced suppression of the immune response were screened in vitro. Exposure of freshly isolated murine epidermal cells (EC) to $180{\;}J/m^{2}$ of UVB radiation resulted in approximately 90% impairtnent of accessory cell function, as measured by their ability to support anti-CD3 monoclonal antibody-induced T-cell mitogenesis. When the culture supenmtants of 150 actinomycete strains were exanuned for their capacity to prevent or repair the UVB-induced impairment of accessory cell function, 4 of them were identified to contain immunomodulators that can restore the decreased accessory cell finiction. The soil isolate that showed the most effective restorative activity, G40025. was selected and fturther characters Addition of 10.mu.l of the culture supernatant of G40025 grown in G-media to cultures of UVB-irradiated EC right after UVB-irradiation restored the decreased accessory cell function by 58%. The immunomodtdator produced by G40025 appeared to be stable at 100.deg. C for 10 min. Taxonomical studies by cultural, morphological, and physiological characterization showed that the soil isolate, G40025, belongs to the genus Streptomyces.

• 산업공학
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• 제14권1호
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• pp.9-19
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• 2001

Production planning and control system plays an important role in manufacturing companies because it determines all production capacity planning, material procurement planning, and production scheduling which are needed in the process of producing products. Many researches on production planning and control system have been conducted for many manufacturing companies for recent decade. But, a considerable research achievement has mainly been obtained on the forecast-driven production for a make-to-stock and an assemble-to-order. The reason is that there are some hardships such as difficulties of standardizing product information, the frequent changes of design and material, and the unexpected dynamic events that influence the production of customer's order in a make-to-order or an engineering-to-order environments. By these characteristics and their complexities, some studies for production planning and control system in a make-to-order environment are presented recently. In this paper, we present the framework of the hietachical production planning and control for a make-to-order environment with dynamic events. In order to illustrate the usefulness of the proposed framework for a hietachical production planning and control, the information system for a make-to-order production was implemented with the object of the company of producing electricity transformer.

• Journal of Biosystems Engineering
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• 제29권4호
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• pp.307-316
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• 2004

This study was conducted to develop a coating system for producing clean enriched rice. The nutritional components of such as brown rice, white rice, clean white rice, enriched rice of US, black rice of China, and rice with perfume of China, were analyzed and compared. Total protein lipid md minerals in brown rice were higher than those in the other rices. A nutrition premix with lysine, thiamine, niacine, calcium lactate, ferrous lactate, and rice starch was made for enriching white rice. A coating device consisted of a tumbler, two spraying nozzles, a rice mixer, etc was developed with the capacity of 1 ton/h. And far-infrared dryers of batch and continuous types were developed to dry hygienically the wet enriched rice. The percentages of lysine, thiamine, amino acid nitride, and Ca and Fe of the enriched rice samples produced in this study were, respectively, 4, 3, 3. 2, and 10 times higher than those of white rice, respectively.