• 기술혁신연구
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• 제9권1호
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• pp.37-75
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• 2001

Technological systems are defined as network(s) consisting of technological infrastructure, industrial organization, and institutional infrastructure. This paper reviews SEMATECH in the U.S. and VLSI Program in Korea as a technological system for semiconductor, which is an advanced technology. Several issues are addressed : how did they get started\ulcorner ; how have they been evolved\ulcorner ; how have the actors and institutions within the system interacted\ulcorner ; what role has the government played in that process\ulcorner Both systems were created by their government, respectively, and they have been evaluated as successful. However, while SEMATECH became complete eough in terms of technological infrastructure, industrial organization, and institutional infrastructure to generate sufficient increasing returns to develop in a self-reinforcing way, a series of VLSI program in Korea is still operated discontinuously under the government subsidy. SEMATECH is more flexible and stable than Korea's VLSI program in that the system has a centralized structure and has been managed and staffed by industry substantially. In addition, both cases show that a technological system may evolve having connections with foreign technological systems and local sub-systems beyond nations, regions and industries. Many other similarities, contrasts, and insights for technological policy from each country's experiences are presented.

• International Journal of Automotive Technology
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• 제6권4호
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• pp.413-419
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• 2005

The United States automotive recycling infrastructure has successfully reduced the amount of automotive waste sent to landfills, especially since the introduction of shredders in the late 1950s. Shredders are necessary to process and recycle automotive hulks and other durable goods. However, this industry faces significant challenges as the automotive manufacturers are increasing the use of nonmetallic components which are difficult to recycle. Additionally, it is becoming obvious that automobiles contain hazardous materials which place heavy burdens on the environment. To address this growing concern, we propose a process planning model for automotive shredders to make tactical decisions regarding at what level to process and at what level to reprocess feed stock materials. The purpose of this paper is to test analytical models to help shredders improve the profitability and efficiency of the bulk recycling processes for end of life automobile returns. The work is motivated by an actual recycling problem that was observed at Capitol City Metals shredding facility in Indianapolis, Indiana.

• 한국가금학회지
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• 제26권1호
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• pp.35-42
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• 1999

According to the importance(production ratio) of special brand eggs, poultry farma can be classified into four types(Types I to IV). A close relation can be observed between these types and farm scale. Special brand eggs used to be the speciality of small-scale, suburban poultry farms. Recently, however, the production of these eggs has been adopted by medium and large farms, too, and is increasing throughout Japan. In particular, small-scale farms specializing in these eggs have attained a high profit and take a characteristic management from as opposed to large-scale poultry farming that adopts the \"small profit and quick returns\" strategy. Because of this, the meaning of special brand egg production to farm management differs according to farm scale. For small poultry farmers, it means securing a high profitability and for medium and large producers, improving the corporate image or meeting the needs for assortment of retailers.

• 한국정밀공학회지
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• 제3권4호
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• pp.43-52
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• 1986

Experimental results on plastic strain induced in truning operation are presented in this paper. The plastic strain is computed by lagrangian strain using grid method, and metal cutting phenomena are also illustrated by micrograph and distribution figures of plastic strain and microvickers hardness of the machining surface. In the cutting of ductile materials, such as carbon steel, generally, the plastic strain is found to be concentrated near the surface. The amount of plastic strain increases with increasing cutting speed and feed rate. The dustribution of microvickers hardness is greater near the cutting surface and decreases from the machining surface under which its hardness returns to the normal hardness of the material.

• 대한화학회지
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• 제15권6호
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• pp.293-303
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• 1971

The theological properties of aqueous suspensions of Black Hills bentonite were measured by using a Couette-type viscometer. Three kinds of flow units in aqueous bentonite suspension were postulated. Each has a different average relaxation time, one Newtonian. One of the non-Newtonian types is thixotropic, and the other is non-thixotropic. The thixotropic non-Newtonian unit is transformed to a Newtonian unit by shear stress. If the stress is relieved, the transformed unit returns to its original state. Two flow equations were derived by introducing chemical kinetics consideration for such a transition into the generalized theory of viscous flow. One equation describes the "upcurve," a diagram of rate of sheat versus shear stress, obtained by increasing the rate of shear, and the other relates to the "downcurve" obtained by decreasing the shear rate. The equations satisfactorilly describe the experimental thixotropic hysteresis of bentonite suspensions. The equations also were successfully applied to the flow curves of the suspensions containing various amounts of monovalent electrolyte (KCI).

• 한국유기농업학회지
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• 제25권4호
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• pp.679-697
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• 2017

This study analyzes an economic efficiency of environmental friendly farm and conventional farm using the data envelopment analysis (DEA). We compare the economic efficiency of Environmental Friendly farm and Conventional farm. We also analyze the effects of some explanatory variables on allocative efficiency (AE), pure technology efficiency (PTE) and scale efficiency (SE). In the case of strawberries farm, environmental friendly farm has higher overall efficiency (OE) than conventional farm. But tomatoes farm has higher overall efficiency (OE) than conventional farm. And We measure returns to scale of farms. Most strawberries and tomatoes farms showed Increasing to Scale (IRS).

• 보건행정학회지
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• 제6권2호
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• pp.91-114
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• 1996

In this research, the Data Envelopment Analysis(DEA) was applied to measure production efficiency of Public Corporation Medical Centers(PCMCs) operating in Korea. The focus of this research is triple. First, identifing convenience and usefulness of DEA to measure the relative efficiency among PCMCs. Second, assessing magnitudes of the relative efficiency for each PCMC. Third, adding insights into some factors resulting inefficiency in PCMCs. Then, in this paper technical efficiency and scale efficiency measured by DEA[introduced by Charnes, Cooper, and Rhoides(1978) and Banker, Charnes, and Cooper(1984)] were analyzed and a new separate variable was introduced which makes it possible to determine whether operations were conducted in regions of increasing, constant or decresing returns to scale(in multiple input and output situations). And a multi-factor Tobit analysis was conducted to see which variables are associated with PCMC's efficiency.

• Agribusiness and Information Management
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• 제1권2호
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• pp.23-42
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• 2009

As technology develops, more advanced technologies involving GPS, GIS, RFID and sensor networks have been adopted in agriculture sector for u-Farm. However, technology adoptions have been evaluated as ineffective. Farmers and agri-business have low level of understanding on technology so it is not efficiently utilized. This study introduces a case of RFID/sensor networks of mushroom farm as a u-Farm case study, focusing on developing a framework for analysis of u-Farm investment returns. RFID and sensor networks improve real-time production control, processing management, and traceability. Integration of RFID and sensor networks leads to innovation into the mushroom farm, reducing labor cost, increasing productivity, and improving quality of the mushroom. The ROI which is used as an indicator of performance indicator is 413%.

• 한국의류학회지
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• 제32권9호
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• pp.1356-1365
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• 2008

As Korean retailers are expanding their return policies, customer abuse and fraud behaviors are increasing. This study attempts to understand customers' unethical return behaviors in the Korean retailing. As an exploratory approach, the study identifies behavioral patterns of unethical returns from retail employees' perspectives. A total of 168 cases collected from 112 individual interviews with retail employees are qualitatively analyzed. Unethical return behaviors are categorized into five groups: lenting/deshopping, product defects with customer faults, unreasonable compensation demands, selfish behaviors, and problem behaviors in the service encounter. The study indicates that a variety of unethical return behaviors are observed despite a short history of return policy in Korea, and renting/deshopping and product defects with customer faults are the most prevalent return abuse behaviors.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.287-290
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• 2004

A structure using the two-way shape memory effect (TWSME) returns to its initial shape by increasing or decreasing temperature under initial residual stress. Through the thermo-mechanical constitutive equation of shape memory alloy(SMA) proposed by Lagoudas et al., we simulate the behavior of a double actuator in which two SMA wires are attached to the tip of panel under the initially given residual stress. Through the numerical results conducted in the present study, the proposed actuator device is suitable for repeated actuation. The simulation algorithm proposed in the present study can be applied extensively to the analysis of the assembled .system of SMA-actuator and host structure in the practical applications.