• 조명전기설비학회논문지
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• 제29권10호
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• pp.39-46
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• 2015

REMICON(Ready Mixed Concrete), the most essential material of construction work, is produced from facility called "Batcher plant." In order to produce Remicon, Batcher Plant needs to be supplied with basic raw material such as ballast, sand, cement, admixture and water. In remicon industry, overland transport vehicles are used during the whole manufacturing process from producing to infilling at the construction site. Thus, the transportation cost sums up be to 20 percent of whole manufacturing cost and transport capacity and distance travelled have direct and major effect on manufacturing costs. This paper suggests a method to find optimal location of batcher plant using modified Steiner point, suggesting the most effective and flexible connection through among construction site, aggregate, cement and remicon producing plant. This paper also proposes reducing of transport cost at maximum 60% by calculation through optimized plant location. The modified Steiner point theory proposed in this paper also can be applied to optimal location of a $2^{ry}$ substation or MCC panel for minimizing of power loss, voltage drop, line distance and etc.

• 한국수소및신에너지학회논문집
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• 제25권1호
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• pp.19-27
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• 2014

Mg hydride has a high hydrogen capacity (7.6%), at high temperature, and is a lightweight and low cost material, thus it a promising hydrogen storage material. However, its high operation temperature and very slow reaction kinetics are obstacles to practical application. In order to overcome these disadvantages of Mg hydride, graphene powder was added to it. The addition of graphene has been shown to reduce the operating temperature of dehydrogenation. Moreover, in this report the environmental aspects of $MgH_x$-Graphene composites are investigated by means of the environmental life cycle assessment (LCA) method. $MgH_x$-Graphene mixture was prepared by hydrogen induced mechanical alloy (HIMA). The synthesized powder was characterized by XRD(X-ray Diffraction). The hydrogenation behaviors were evaluated by using a Sievert's type automatic PCT apparatus. Such evaluation of Materials also conducted in the LCA. From the result of P-C-T(Pressure-Composition-Temperature) curves, the $MgH_x$-3wt.% graphene composite was evaluated as having a 5.86wt.% maximum hydrogen storage capacity, at 523K. From absorption kinetic testing, the $MgH_x$-7wt.% graphene composite was evaluated as having a maximum 6.94wt.%/ms hydrogen absorption rate, at 573K. Environment evaluation results for the $MgH_x$-graphene composites and other materials indicated environmental impact from the electric power used and from the materials themselves.

• 자원ㆍ환경경제연구
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• 제24권2호
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• pp.311-342
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• 2015

본 논문에서는 경제이론과 실증분석을 통하여 이명박 정부가 석유제품 시장에 개입한 논거를 평가하였다. 한국을 포함하여 세계적으로 정제산업은 과점이 보편적이며, 역차별적인 수준의 대외 시장개방에도 불구하고 석유제품 시장에서 국내 정유4사의 시장점유율이 높게 지속되는 이유는 정유4사가 국제적인 가격경쟁력을 보유하고 있고 MOPS 가격을 기준으로 경쟁적인 가격책정을 하고 있기 때문이다. 국내 세전 소비자가격은 일본의 가격과 '27개 EU권 국가의 가격들을 가중평균한 값'보다 통계적으로 유의하게 현저히 낮았다. 한국, 일본, 14개 EU권 국가들을 대상으로 가격 비대칭성의 존재여부와 상세내역을 분석한 결과, 휘발유의 경우 한국과 11개 EU권 국가, 경유의 경우 한국과 8개 EU권 국가에서 비대칭성이 있는 것으로 판별되었다. 가격 비대칭성은 다양한 경제 경영적 원인에 의해 다양한 제품과 시장구조에서 발생한다. 소비자 복지의 관점에서는 한국의 세전 소비자가격이 현저히 낮다는 점이 제일 중요하다.

• 대한교통학회지
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• 제28권3호
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• pp.85-98
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• 2010

대중교통 네트워크가 점점 더 복합수단화됨에 따라 네트워크의 연계성이 중요한 개념으로 대두되고 있다. 본 연구에서는 복합수단 대중교통 네트워크의 연계성을 평가하는 계량모형을 제시하였다. 이를 위하여 우선 대중교통 노선의 평가지표로 노선연장, 수송용량, 통행속도를 선정하고 이들의 곱을 노선의 연계강도로 정의하였다. 또한 사회 네트워크 분석에서 사용되는 노드의 중심성 지표 중 하나인 degree centrality 개념을 대중교통 네트워크에 적합하게 수정하였다. 노선의 연계강도와 그 노선이 서비스하는 정류장의 degree centrality를 접목하여 정류장의 연계정도를 나타내는 지수를 개발하였다. 이를 토대로 복합수단 대중교통 네트워크 내의 노선 및 지역의 연계성 지수도 도출하였다. 또한 정류장의 연계성 지수와 이용자수용비율 함수를 이용하여 환승센터의 연계성을 평가하는 방법도 제시하였다. 사례연구 결과 본 연구에서 개발된 연계성 평가 모형은 복합수단 대중교통 네트워크의 특성을 제대로 반영하고 있으며, 대중교통 네트워크 내의 정류장, 노선, 지역의 연계성을 적절하게 평가할 수 있고, 또한 환승센터의 서비스수준 산정에 활용될 수 있음을 확인하였다.

• 한국경제지리학회지
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• 제11권2호
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• pp.216-232
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• 2008

본 연구는 박제가의 [북학의]를 통해 그의 지리적 관심과 지리지식이 어느 정도이며 어떤면에 활용하고자 하였는지를 살피는데 있다. 특히 경제지리적 내용을 추출해서 농업 공업 상업지리 내용으로 분류 해석하였다. 농업지리 내용으로 농지, 종자파종, 시비, 가축사육, 농잠과 과일 등에 대해 섬세하고 치밀하게 필요성과 구체적 방법론을 제시하고 있다. 공업지리 내용으로 연경(북경)에 와 있는 서양학자들로부터 첨단과학 및 공학 기술과 지식을 받아들여 우리 것에 대한 근대화를 꾀할 것을 강조하였다. 상업지리 내용으로 양반들의 유휴 노동력을 실용적인 상업생산 노동력으로 전환시키며 수레를 통한 육로교통을 열고 이웃 나라(청, 일본, 유구, 베트남 등)들과 뱃길 통상의 길을 열어 지역 및 국가 경제의 활성화를 꾀할 것을 주장하였다. 연구를 통해 박제가는 경제지리 내용에 밝았고 깊은 관심을 기울였으며 경제지리 관련 지식을 활용해 국가경제력 제고를 위해 노력한 실학자임을 알수 있다. 그의 경제지리적 관심과 지식은 실사구시에 직결되는 것이다. 당시 박제가의 경제지리적 지식과 활용의 구체적 방법론 제시가 나라에 의해 효율적으로 채택되었다면 조선시대 후기의 국가 경제력은 크게 도약할 수 있었을 것이다.

• 수산경영론집
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• 제34권2호
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• pp.75-90
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• 2003

When we think of fundamental problems of the aquaculture industry, there are several strict conditions, and consequently the aquaculture industry is forced to change. Fish aquaculture has a structural supply surplus in production, aggravation of fishing grounds, stagnant low price due to recent recession, and drastic change of distribution circumstances. It is requested for us to initiate discussion on such issue as “how fish aquaculture establishes its status in the coastal fishery\ulcorner, will fish aquaculture grow in the future\ulcorner, and if so “how it will be restructured\ulcorner” The above issues can be observed in the mariculture of yellow tail, sea scallop and eel. But there have not been studied concerning seabream even though the production is over 30% of the total production of fish aquaculture in resent and it occupied an important status in the fish aquaculture. The objectives of this study is to forecast the future movement of sea bream aquaculture. The first goal of the study is to contribute to managerial and economic studies on the aquaculture industry. The second goal is to identify the factors influencing the competition between production areas and to identify the mechanisms involved. This study will examine the competitive power in individual producing area, its behavior, and its compulsory factors based on case study. Producing areas will be categorized according to following parameters : distance to market and availability of transportation, natural environment, the time of formation of producing areas (leaderㆍfollower), major production items, scale of business and producing areas, degree of organization in production and sales. As a factor in shaping the production area of sea bream aquaculture, natural conditions especially the water temperature is very important. Sea bream shows more active feeding and faster growth in areas located where the water temperature does not go below 13∼14$^{\circ}C$ during the winter. Also fish aquaculture is constrained by the transporting distance. Aquacultured yellowtail is a mass-produced and a mass-distributed item. It is sold a unit of cage and transported by ship. On the other hand, sea bream is sold in small amount in markets and transported by truck; so, the transportation cost is higher than yellow tail. Aquacultured sea bream has different product characteristics due to transport distance. We need to study live fish and fresh fish markets separately. Live fish was the original product form of aquacultured sea bream. Transportation of live fish has more constraints than the transportation of fresh fish. Death rate and distance are highly correlated. In addition, loading capacity of live fish is less than fresh fish. In the case of a 10 ton truck, live fish can only be loaded up to 1.5 tons. But, fresh fish which can be placed in a box can be loaded up to 5 to 6 tons. Because of this characteristics, live fish requires closer location to consumption area than fresh fish. In the consumption markets, the size of fresh fish is mainly 0.8 to 2kg.Live fish usually goes through auction, and quality is graded. Main purchaser comes from many small-sized restaurants, so a relatively small farmer and distributer can sell it. Aquacultured sea bream has been transacted as a fresh fish in GMS ,since 1993 when the price plummeted. Economies of scale works in case of fresh fish. The characteristics of fresh fish is as follows : As a large scale demander, General Merchandise Stores are the main purchasers of sea bream and the size of the fish is around 1.3kg. It mainly goes through negotiation. Aquacultured sea bream has been established as a representative food in General Merchandise Stores. GMS require stable and mass supply, consistent size, and low price. And Distribution of fresh fish is undertook by the large scale distributers, which can satisfy requirements of GMS. The market share in Tokyo Central Wholesale Market shows Mie Pref. is dominating in live fish. And Ehime Pref. is dominating in fresh fish. Ehime Pref. showed remarkable growth in 1990s. At present, the dealings of live fish is decreasing. However, the dealings of fresh fish is increasing in Tokyo Central Wholesale Market. The price of live fish is decreasing more than one of fresh fish. Even though Ehime Pref. has an ideal natural environment for sea bream aquaculture, its entry into sea bream aquaculture was late, because it was located at a further distance to consumers than the competing producing areas. However, Ehime Pref. became the number one producing areas through the sales of fresh fish in the 1990s. The production volume is almost 3 times the production volume of Mie Pref. which is the number two production area. More conversion from yellow tail aquaculture to sea bream aquaculture is taking place in Ehime Pref., because Kagosima Pref. has a better natural environment for yellow tail aquaculture. Transportation is worse than Mie Pref., but this region as a far-flung producing area makes up by increasing the business scale. Ehime Pref. increases the market share for fresh fish by creating demand from GMS. Ehime Pref. has developed market strategies such as a quick return at a small profit, a stable and mass supply and standardization in size. Ehime Pref. increases the market power by the capital of a large scale commission agent. Secondly Mie Pref. is close to markets and composed of small scale farmers. Mie Pref. switched to sea bream aquaculture early, because of the price decrease in aquacultured yellou tail and natural environmental problems. Mie Pref. had not changed until 1993 when the price of the sea bream plummeted. Because it had better natural environment and transportation. Mie Pref. has a suitable water temperature range required for sea bream aquaculture. However, the price of live sea bream continued to decline due to excessive production and economic recession. As a consequence, small scale farmers are faced with a market price below the average production cost in 1993. In such kind of situation, the small-sized and inefficient manager in Mie Pref. was obliged to withdraw from sea bream aquaculture. Kumamoto Pref. is located further from market sites and has an unsuitable nature environmental condition required for sea bream aquaculture. Although Kumamoto Pref. is trying to convert to the puffer fish aquaculture which requires different rearing techniques, aquaculture technique for puffer fish is not established yet.

• Journal of Microbiology and Biotechnology
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• 제25권6호
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• pp.820-827
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• 2015

The present study was performed to investigate the various radical scavenging activities of fermented Undaria pinnatifida by the mycelia fermentation method. U. pinnatifida was fermented with Cordyceps militaris (C. militaris ) mycelia using solid culture and compared with unfermentated U. pinnatifida and C. militaris mycelia for antioxidant activities. The various radical scavenging activities of extracts from U. pinnatifida fermented with C. militaris mycelia (FUCM) were evaluated by electron spin resonance. The antioxidant activities of the FUCM extracts were assayed for ferric reducing antioxidant power, 2,2'-azinobis-(3-ethybenzothiazoline-6-sulfonic acid) radical scavenging activity, and oxygen radical absorption capacity. The free radical scavenging activity of FUCM extracts was higher than that of C. militaris mycelia or U. pinnatifida alone. FUCM extracts were significantly (p < 0.05) increased up to 35 times, 10 times, and 16 times that of U. pinnatifida extracts on DPPH, alkyl, and hydroxyl radical scavenging activities, respectively. These results indicate that FUCM extracts have different chemical ingredients from U. pinnatifida and could provide beneficial antioxidant activity.

• Asian-Australasian Journal of Animal Sciences
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• 제25권11호
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• pp.1641-1648
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• 2012

This study was performed to investigate the combined effect of dietary supplementation of gallic and linoleic acid (GL) on the antioxidative effect and quality of thigh meat from broilers. Broilers received 3 dietary treatments: i) commercial finisher diet (control), ii) 0.5% GL (gallic:linoleic acid = 1 M:1 M), and iii) 1.0% GL during the 22 to 36 d. The pH value of broiler thigh meat was increased by GL supplementation. Water holding capacity of the thigh meat was enhanced by the 1.0% dietary GL supplementation. Antioxidative effect (total phenolic content, DPPH radical scavenging activity, $ABTS^+$ reducing activity, reducing power, and TBARS value) in the thigh from the broilers improved significantly with 1.0% GL. Linoleic acid and docosahexaenoic acids were higher in the broilers fed both levels of dietary GL. However, volatile basic nitrogen content and microbiological quality was not shown to be different between control and treated group. Results indicate that 1.0% dietary supplementation of GL can improve the antioxidant activity of broiler thigh meat and may enhance the meat quality.

• 중소기업융합학회논문지
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• 제4권3호
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• pp.41-46
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• 2014

창조경제는 전체산업이 융합하는 현상과 관련이 있으며, 융합은 기술 및 창의적인 아이디어의 다차원적 결합을 의미한다. 첨단기술과 대규모자본을 투입하지 않더라도 창의적인 컨셉과 융합아이디어를 바탕으로 성공사례를 만들 수 있는 강점이 있으며 제조업 분야에서는 최근 들어 IT 기술과의 융합을 기반으로 한 제3차 제조업혁명이 확산되고 있으며, 생태계 내의 네트워크화를 통해 기업의 경쟁력을 향상시키는 동인으로 작동하고 있다. 그간 국내에서의 융합은 주로 대기업에서 관심을 가지고 추진한 것이 사실이다. 중소기업의 경우 융합에 대한 관심은 높으나 구체적인 추진은 부족하여, 이에 대한 정책적인 고려가 요구되는 상황이다. 창조적인 아이디어가 가미된 융합은 중소기업에게 성공을 위한 새로운 기회를 제공할 수 있으므로 대기업에 비해 상대적으로 자원이 부족한 중소기업도 융합 아이디어만 있으면 부가가치를 높이고 신사업을 창출함으로써 성공 가능하므로 단순히 기술 결합에 의한 기술제품의 개선이나 시장 확대가 아니라 창조적인 아이디어를 부가하는 것이 관건이 된다. 따라서 중소기업 융합 활성화를 위해서는 첫째, 융합을 통한 중소기업 R&D 역량 강화 방안 둘째, 중소기업 융합성과의 보호 및 활용도 제고 셋째, 중소기업융합 인프라를 확충시킬 수 있는 과제가 우선적으로 추진될 필요가 있다.

• International journal of advanced smart convergence
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• 제4권2호
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• pp.109-119
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• 2015

The interaction between wireless sensors such as Internet of Things (IoT) and Cloud is a new paradigm of communication virtualization to overcome resource and efficiency restriction. Cloud computing provides unlimited platform, resources, services and also covers almost every area of computing. On the other hand, Wireless Sensor Networks (WSN) has gained attention for their potential supports and attractive solutions such as IoT, environment monitoring, healthcare, military, critical infrastructure monitoring, home and industrial automation, transportation, business, etc. Besides, our virtual groups and social networks are in main role of information sharing. However, this sensor network lacks resource, storage capacity and computational power along with extensibility, fault-tolerance, reliability and openness. These data are not available to community groups or cloud environment for general purpose research or utilization yet. If we reduce the gap between real and virtual world by adding this WSN driven data to cloud environment and virtual communities, then it can gain a remarkable attention from all over, along with giving us the benefit in various sectors. We have proposed a Pub/Sub-based sensor virtualization framework Cloud environment. This integration provides resource, service, and storage with sensor driven data to the community. We have virtualized physical sensors as virtual sensors on cloud computing, while this middleware and virtual sensors are provisioned automatically to end users whenever they required. Our architecture provides service to end users without being concerned about its implementation details. Furthermore, we have proposed an efficient content-based event matching algorithm to analyze subscriptions and to publish proper contents in a cost-effective manner. We have evaluated our algorithm which shows better performance while comparing to that of previously proposed algorithms.