• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.529-533
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• 2012

By introducing RPS(Renewable Portfolio Standard) for reduction of greenhouse gas, Renewable energy sources have becoming widespread gradually. However, Renewable energy sources, such as wind power and PV are difficult to control the output and they have intermittent characteristics of the output. These characteristics would cause some problems when it is connected in the power system. In order to solve these problems, Energy Storage Systems(ESS) are considered to use. Although there are many different storage devices, the utilization of Secondary Battery is the one of the best ways to stabilize an output fluctuation of RES because of its fast responsibility. For that reason, it would better fit a large-capacity of Secondary battery for stabilization. However, batteries cannot be installed with a large capacity blindly because of its expensive cost. So to select proper capacity of the battery is an important consideration. This paper presented a methodology for the optimal capacity and operation of ESS in microgrids.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2002년도 제30차 추계 학술대회
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• pp.165-165
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• 2002

• 한국축산식품학회지
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• 제40권6호
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• pp.908-923
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• 2020

The objective of this study was to compare tastes-related components and eating quality properties between Hanwoo steer and cow meats. Longissimus thoracis (LT) muscles with same quality grade (1⁺ grade) collected from left sides of the steer and cow carcasses were used for analyses of technological quality traits, free amino acids (FAAs), metabolites, nucleotides, fatty acids and sensory attributes. there were no differences occurring in the chemical composition (fat, protein, moisture and collagen) and technological quality traits (cooking loss, water holding capacity, shear force and color) between the two beef types (p>0.05). The cow meat exhibited significantly higher amounts of some FAAs associated with umami (e.g., glutamic acid and lysine), sweetness (e.g., proline and glutamic acid) and saltiness (e.g., histidine and glutamic acid) compared to the steer meat (p<0.05). Regarding the nucleotides, no differences occurred in all the identified nucleotides between the two beef types (p>0.05). A total of 27 metabolites were identified, however, only some compounds (e.g., acetate, creatine, creatinine, glucose and inosine, etc.) showed their significantly higher amounts in the cow meat compared with those in the steer meat (p<0.05). In terms of sensory aspects, the panelists found no differences in scores of all the eating quality traits between the two sex types of beef (p>0.05). Overall, excepts some variations in tastes-active compounds, there were no differences in the quality characteristics in general and eating quality in particular between the cow and steer meats when they were in the same quality grade.

• 한국입자에어로졸학회지
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• 제12권4호
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• pp.127-134
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• 2016

A multiwall carbon nanotube (MWCNT)/graphene (GR) composite was synthesized for an enhanced supercapacitor. Aerosol spray pyrolysis (ASP) was employed to synthesize the MWCNT/GR composites using a colloidal mixture of MWCNT and graphene oxide (GO). The effect of the weight ratio of the MWCNT/GO on the particle properties including the morphology and layered structure were investigated. The morphology of MWCNT/GR composites was generally the shape of a crumpled paper ball, and the average composite size was about $5{\mu}m$. MWCNT were uniformly dispersed in GR sheets and the MWCNT not only increase the basal spacing but also bridge the defects for electron transfer between GR sheets. Thus, it was increasing electrolyte/electrode contact area and facilitating transportation of electrolyte ion and electron in the electrode. Electrochemical data demonstrate that the MWCNT/GR (weight ratio=0.1) composite possesses a specific capacitance of 192 F/g at 0.1 A/g and good rate capability (88% capacity retention at 4 A/g) using two-electrode testing system.

• Bulletin of the Korean Chemical Society
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• 제34권8호
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• pp.2408-2412
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• 2013

We demonstrate herein the synthesis and modification of magnetic nanoparticles and its use in the immobilization of the lipase. Magnetic $Fe_3O_4$ nanoparticles (MNPs) were prepared by simple co-precipitation method in aqueous medium and then subsequently modified with tetraethyl orthosilicate (TEOS) and 3-aminopropyl triethylenesilane (APTES). Silanization magnetic nanoparticles (SMNP) and amino magnetic nanomicrosphere (AMNP) were synthesized successfully. The morphology, structure, magnetic property and chemical composition of the synthetic MNP and its derivatives were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) analysis, X-ray diffraction, superconducting quantum interference device (SQUID) and thermogravimetric analyses (TGA). All of these three nanoparticles exhibited good crystallization performance, apparent superparamagnetism, and the saturation magnetization of MNP, SMNP, AMNP were 47.9 emu/g, 33.0 emu/g and 19.5 emu/g, respectively. The amino content was 5.66%. The AMNP was used to immobilize lipase, and the maximum adsorption capacity of the protein was 26.3 mg/g. The maximum maintained activity (88 percent) was achieved while the amount of immobilized lipase was 23.7 mg $g^{-1}$. Immobilization of enzyme on the magnetic nanoparticles can facilitate the isolation of reaction products from reaction mixture and thus lowers the cost of enzyme application.

• 정보관리학회지
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• 제35권4호
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• pp.285-308
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• 2018

지식활용은 조직의 역량 제고와 직접적으로 연결하는 활동이며 새로운 가치를 다시 생산하게 하는 지식관리의 가장 핵심적 활동이라 할 수 있다. 따라서 지식활용 활동에 영향을 미치는 요인 및 환경에 대한 체계적이며 종합적인 연구는 더욱 필요하다고 본다. 본 연구의 목적은 지식관리 활동 중 마지막 단계인 지식활용에 직접적으로 영향을 미치는 정보문화와 조직문화를 파악하고자 지식활용에 영향을 미치는 정보문화 및 조직문화 요인을 규명하는 것이다. 이를 위하여 정부출연연구소, 도서관, 기업연구소에 근무하는 사서직, 연구직, 일반직 300명을 대상으로 설문조사를 수행하였고 이를 통하여 수집된 데이터는 다중회귀분석을 적용하여 정보문화의 여섯 가지 속성과 조직문화의 네 가지 유형이 지식활용의 문제대처, 지식재생산, 지식확산에 미치는 영향관계를 분석하였다. 분석결과, 정보문화(제어성, 공개성, 적극성)와 조직문화(관계지향문화, 혁신지향문화, 과업지향문화)가 지식활용의 중요한 요인으로 나타났으며, 이러한 연구결과를 토대로 조직의 지식활용에 있어서 시사점을 논의하였다.

• 대한전기학회논문지:전력기술부문A
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• 제50권7호
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• pp.303-308
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• 2001

This paper presents algorithm to plan construction and expanding of substation considering contingency accidents by proposing utilization factor according to configuration of substation bank system. In this paper, firstly, proper sphere of supply area by each district which could be standardized with respect to its supply capacity is established under assumption of long term load forecasting. Secondly, goal of utilization ratio based on configuration of substation bank was set to keep reliability by remaining sound bank when it happen to one bank accidents. Finally, it is set up for optimal construction and expanding of substation considering economy and reliability simultaneously about substation to exceed these ratio. To verify proposed algorithm, at first, after adopting a part of Kangnam area in Seoul as area for testing, it is divided into several regions for this area according to power branches of power utility. Secondly, by deriving correlation factor between load demand and economic indicators in these region respectively, the regional load forecasting was performed with economic growth and city plan scenario. Finally, based on the predicted load demand by region and land use data which is identified from air-photographic, the load demand by district was predicted. Also, planning for substation considering contingency is formulated to expand taking into account computing utilization factor which is based on configuration of substation bank respectively.

• 한국IT서비스학회지
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• 제11권1호
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• pp.39-58
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• 2012

This study was carried out to figure out the relationship between EAmaturity, information management capacity, and information performance, and find the effect between these variables and the reciprocal causation. The study found that EAmaturity has a positive effect on information resource management and performance. In other words, the effect of input, calculation, management and utilization factors on information planning in EAmaturity showed that calculation, management and utilization factors have a significant effect on the information planning. While the effect of input, calculation, management and utilization factors on information introduction and management showed that only both calculation and utilization have a significant effect on the information management factor. It says that EAinput in EAmaturity does not play a big part in the planning stage, as well as not go through a series of process that is connected to the maturity stage by immediate field application. Consequently, EAmaturity varies from the level that EAcreates introduction and performance according to organization. This suggests that the maturity and performance can be also changed by the level that EAcreates information performance by accepting and using this capability within organization as well as the capability to introduce and fully perform the EAsystem presented in enterprise architecture framework of public sector.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.969-978
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• 2010

In this study, a laboratory model test on utilization of recycled aggregates and crushed stone as vertical drains to use alternative material of sand in soft ground is performed. The vertical and horizontal coefficient of permeability of the recycled aggregates and crushed stone showed largely 1.2~4.0 times and 3.0~3.3 times greater than sand, respectively. Therefore, it showed enough to be an alternative material to the sand which had been being used as the vertical and horizontal drainage material before. The variations of pore water pressure with time showed constantly regardless of the load in all vertical drainage materials. When water level drops suddenly, the pore water pressure of the recycled aggregate and crushed aggregate is reduced to nearly zero. Therefore, it was applicable to the field because discharge capacity was similarity to that of sand. The settlement in crushed aggregates and recycled aggregate decreases gradually with the load increase. When water level drops suddenly, earth pressure in all drains materials was evaluated the equivalent drainage capacity similarity to sand because it show approaching the nearly zero.

• 산업공학
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• 제17권4호
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• pp.472-481
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• 2004

In this paper, we propose a linear programming model of supply planning process for the supply chain collaboration strategy of a company. The amount of its supplying quantity relies on outsourcing suppliers heavily. Conversely, the revenues of those suppliers are highly dependent on the supplying quota from the supply network planning of the company. In order to keep the supply stable through collaboration, the company builds such a policy to guarantee the fairness on revenue between the supplies. For this, the supply network plan should keep the capacity utilization ratio even for all the suppliers. But the production capacities are different and the distribution of molds is disproportional through suppliers, so the supply network plan is not easily established with simple arithmetic processes. Therefore, we developed the linear programming model with those target function and constraints minimizing the costs for holding inventory and penalty of delayed delivery, simultaneously guaranteeing the even capacity utilization through suppliers. The proposed model has been applied to real case and the evaluation for the planning result from the model would be followed in order to make sure that our model guarantee on extracting the supply network plan subordinated to the policy. Also we mention about further studies for improvement of the model.