• Korean Journal of Plant Resources
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• v.8 no.3
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• pp.297-302
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• 1995

The experiment is conducted to reduce the labor and production cost with the labor save of harvest if cultivating the potatoes using the machine and the results are as follows. On labor saving effect in transparent vinyl mulching, digging working hours per 10a in the case of using tractor are 60 min., fixing + turning time is 5 min. and 30sec., the time of harvest is 65 min and 30sec., digging working hours using cultivator are 99 min. and fixing +turning time is 5 min. and 30sec., but the time of hand harvesting is 990 min. and in digging labor saving effect, tractor shows 94% in the harvesting period and harvest by cultivator 90%. On non mulching cases, the harvest by tractor takes 49 min. and 30 sec. and that by cultivator does 87 min. and 30 sec., and digging labor saving effect shows 94% in the tractor harvest and 90% in the cultivator harvest. Therefore, on the operation efficiency per hour, in the case of tractor with digger vinyl mulching and non mulching show, $0.091\sim0.121ha$ and in the case of cultivator with digger both show $0.057\sim0.069ha$, so in the mechanized harvest of potatoes, the harvest by tractor with digger is the best. On the cost and labor save for harvesting the potatoes with labor saving effect, tractor shows 19 hours and 20 min./10a in vinyl mulching and 19 hours. and 54 min./10a in non mulching, so it shows the short hours for harvesting. And labor saving effect shows $42\sim45%$ in comparison with 35 hours and 21 min. $\sim35$ hours and 23 min.($123,113\sim130,613$ won) of the hand harvest, so the cost was reduced to $71,250\sim72,225$ won. On the cultivator with diggers, vinyl mulching takes 19 hours and 55 min. and non mulching 19 hours and 38 min., so the labor saving effect and cost were reduced to $14\sim44%$ ($72,675\sim73,313$ won) in comparison with the hand harvest.

• Journal of Korean Society of Transportation
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• v.24 no.3 s.89
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• pp.143-153
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• 2006

This paper annually estimates the economies of density, scale and scope with the data of cost and output of 27 leading air carriers to suggest the political findings and strategies of raising the cost efficiency of our air transport industry. The estimation results and their implications are as follows. First, KAL and Aha would reduce their cost if they could increase international route density. Second, KAL and AAR would reduce their cost if they could expand the network but save their cost more effectively if they could increase international route density rather than expand the network. Third, the minimum efficient scale that minimize average cost of two national flag carriers which operate by the present output ratio among domestic passenger, international passenger and freight appears to be larger than each present output level of KAL and AAR. Meanwhile, it appears that minimum efficient scale of small size low cost carriers which operate domestic-oriented route is much smaller than minimum efficient scale of national flag carriers. Finally, it appears that there exists the diseconomies of scope between domestic passenger and the other outputs, that is, international passenger and freight and therefore save their cost if freight output ratio is higher and domestic passenger output ratio is lower than the Present level.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.210-216
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• 1998

The most important thing to consider in cold store design are to save cooling energy consumption and to keep goods freshly. Specially there are many efforts to save energy with cold store in Korea. A building energy simulation program should be used to optimally select a cooling system to match the criteria of cooling rate and storage rate in a given cool crop storage building and HVAC system. The low maintenance costs, high degree of safety and environmental impacts are also favouring the underground solution. There are obviously a lot of possibility for cost-effective storage of cooled or frozen goods or liquids in ground water rock.

• Architectural research
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• v.7 no.1
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• pp.1-9
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• 2005

The needs of collaboration among design participants spread in different locations is emphasized in the early design stage in order to not only save time and provide places to meet and talk, but also to save cost for those events as well: This is being realized by the Internet, which helps support a networked, integrated real-time multi-user environment. As the base for collaboration activities moves from physical places to cyberspace, the methods of connecting every participant by means of a computer technology have been desired and considered. This study aims at investigating today's collaboration technology in the architectural design process, especially focused on the early stages, in terms of temporal dimensions. In addition, major concepts for and previous efforts and tools of collaborative design have been examined, and a specific recommendation has been proposed for future development of collaborative architectural design systems: That is distributed collaboration, which is accessible and comprehensible to all the professionals in the building design team, which not only allows the sharing of information but also the sharing of understanding, and which facilitates the development of design tools for different aspects of the envisioned collaborative design environment.

• Proceedings of the KSR Conference
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• 2004.06a
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• pp.290-295
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• 2004

Electrification of existing railroad as well as extension of double track, need a large amount of electric energy. Especially, increase in energy consumption of high cost causes much problems in domestic economy. It is neccessary to save energy for the crisis of exhaust of fossil energy. About $20{\~}25\%$ of regenerated energy of an electric railcar is lost on down slope run or on braking. In order to save energy in electric railway system, Therefor, application of energy regeneration system is proposed and introduced in the present paper.

• Land and Housing Review
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• v.3 no.2
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• pp.177-185
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• 2012

LH applies a uniformly standardized PHC Pile to 15~25 stories of Shear-wall type Apartment Building. Recently it is predicted that LH will construct over 30~40 story Apartment Building to keep varied project condition and faces urgent needs to save construction cost for improving its competitiveness. Therefore, structural analysis and design on the upper part and foundation of apartment building were carried out in this study by subdividing story of apartment building, e.g. 15, 20, 25, 30, 35, 40 stories. Reflecting the result of basement analysis and design, the economic evaluations are performed and the optimum diameters of PHC piles are suggested. The result of this paper is considered to be applied usefully for foundation design of LH apartment housing, and the suggested PHC Piles can be used effectively by increasing efficiency and saving the construction cost of foundation.

• The Journal of the Korea Contents Association
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• v.8 no.4
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• pp.48-54
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• 2008

This paper analyzes cost tradeoffs between memory usage and computation for window-based operators in data stream environments. It identifies generic operator network constructs, and sets up a cost model for the estimation of the expected memory reduction and the computation overheads when window memory relocations are applied to each operator network construct. This cost model helps to identify the utility of window memory relocations. It also helps to apply window memory relocation to improve a query execution plan to save memory usage. The proposed approach contributes to expand the scope of query processing and optimization in data stream environments. It also provides a basis to develop a cost estimation model for the query optimization using window memory relocations.

• Korean Journal of Community Nutrition
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• v.7 no.6
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• pp.863-871
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• 2002

To compare the costs incurred by infant feeding between mothers who breastfed their infants and those who fed them infant formula, a questionnaire survey was carried out to 136 mothers living in Seoul, Cheongju and Chungju who breastfed and 199 mothers who formula-fed their infants. The cost of formula-feeding was estimated based on the expenditures for formula and feeding apparatus, and the time needed to wash bottles and prepare formula. The cost of breastfeeding was estimated based on the expenditures for food for the additional nutritional intake of these mothers. The mean cost of formula-feeding was ￦ 1,870,125 during the first year of the baby＇s life. The food cost for the additional nutritional intake of the breastfeeding mothers was ￦ 203.004 per year. The extra medical cost for respiratory illnesses in the formula-fed group compared to the breastfed group was W 62,920 because the formula-fed infants required medical attention for respiratory illnesses more often than the breast-fed infants. Therefore, breastfeeding could save ￦ 1,730,041 during the first year of an infant＇s life. We may have underestimated the cost savings from breastfeeding because we did not take into account the potentially decreased costs of fertility control and the health benefits for mothers. as well as the decreased usage of water and gas. Analyses showed that breastfeeding is not only nutritionally advantageous, but also economically advantageous for families and society.

• Journal of the military operations research society of Korea
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• v.11 no.1
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• pp.8-32
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• 1985

The objective of this study is to develop the Transportation Model of Linear Programming in which optimal transportation pattern by regions (origins and destinations) to minimize the total transportation costs can be obtained for handling government-held grains. As a result of computing the Transportation Model, the total transportation costs of transporting 1,058,507 metric tons from origins to destinations are 7,234 million won. So, the transporation cost is 6,834 won per ton in this model. But actual transportation cost in 1983 is 11,498 won per ton. Therefore when we distribute and transport the government-held grains from production factories to consumption warehouses, using this Transportation Model of Linear Programming is benefitable. Especially excluding the cost of computer, we could save more than two billion won of Government budget per year.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1976-1981
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• 2003

Except a desktop computer and workstation, an embedded system is a system containing microprocessors. While a desktop computer and a workstation are designed for a general purpose, an embedded system is designed for a dedicated purpose. Thus, an embedded system must meet some constraints such as low power consumption, low cost, small size, real-time, or user-defined ones. A simple and low cost embedded system may be able to be designed without using embedded operating systems (OS). However, considered design time and effort, some embedded system had better be designed with using embedded OS. Under given constraints and purpose of some embedded systems, one embedded OS can save more time, cost, and effort in designing those embedded systems than others. This paper compares four embedded OSs, Windows CE, Embedded Linux, pSOS, and uC/OS. It analyzes several issues of embedded OS such as process scheduling, inter-process communication (IPC), memory management, and network support. Also, it describes the product of each embedded OS.