• Journal of Korean Society of Forest Science
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• v.76 no.4
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• pp.348-356
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• 1987

A new simple method to estimate the earth quantity which is basic data for making the plan of mountain forest road is tried to develop as one of ways to reduce time cost of plan making. The zero-line surveying method, the concept of 2/3 road width in cut-away part and of same quantity between cut-away and fill-up earth which are the backgrounds to develop this method is introduced and explaned also it's theoritical propriety. Under the precondition which have to apply above concepts for constructing the mountain forest road the exchange table for estimating the earth quantity is made like table 3 and 4 through being calculated by a trigonometric function. Table 3 can be used to estimate the earth quantity on the cut-away road-width according to slope of terrain and different road-width, and table 4 can be applied to calculate the quantity of cut-away earth when to know the road-width of cut-away. When using these tables the performance of field surveying and office work for road plan will be highly increased.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.5
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• pp.326-334
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• 2019

Development of Small UAV using HILS (Hardware In the Loop Simulation) can be effectively used to improve the reliability of UAV (Unmanned Aerial Vehicle) while reducing cost and time. It is also possible to reduce the damage to people or property by simulating the malfunction of the Flight Control Computer (FCC) that may occur during the actual flight. For applying such HILS, a real-time simulation environment capable of providing an environment similar to an actual flight condition is required. In this paper, we constructed a real - time HILS environment for Small UAV using 6 D.O.F motion table. In order to link the 6 D.O.F motion table developed in the previous research with the HILS environment in real time, the motion algorithm was changed from the position control method to the velocity control method. Also, we implemented modeling of inverse kinematics model for command transmission in Matlab $Simulink^{(R)}$ and verified the action of motion table according to the simulation model.

• Environmental and Resource Economics Review
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• v.13 no.2
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• pp.195-218
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• 2004

This paper explores the impact of pollution abatement cost on trade balance. First, We derive price pressure of spending pollution abatement cost using I-O table. Then the analysis is extended to the impact on trade balance by manufacturing sectors. The paper explicitly includes indirect effect of pollution abatement cost that is the effect through the change of the other sector prices and excluded in the previous studies. The results show that the impact of pollution abatement cost on trade balance is 0.30~0.46% of total trade volume of Korea. This is lower than that of the United States in 1970's.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.14 no.5
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• pp.1199-1208
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• 1994

In the country, supervision cost is being estimated by percentages of construction cost or cost plus a fixed fee without a reasonable standard. This type has no function for adjusting supervision cost according to variables, such as construction work complexity, extent of supervisory services, fluctuations in prices. In this study, an objective criterion to estimate supervision cost with improved supervisory services has been developed, in which adjusting functions as stated above should be properly considered. A comparative study of supervisory service systems in foreign countries and a survey through questionnaire were carried out for the study. An objective criterion from the results is proposed in the form of an expression or table.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.2
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• pp.399-407
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• 1996

A fuzzy learning algorithm to get the optimal fuzzy rules is presented in this paper. The algorithm introduces a reference model to generate a desired output and a performance index funtion instead of the performance index table. The performance index funtion is a cost function based on the error and error-rate between the reference and plant output. The cost function is minimized by a gradient method and the control input is also updated. In this case, the control rules which generate the desired response can be obtained by changing the portion of the error-rate in the cost funtion. In SISO(Single-Input Single- Output)plant, only by the learning delay, it is possible to experss the plant model and to get the desired control rules. In the long run, this algorithm gives us the good control rules with a minimal amount of prior informaiton about the environment.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.41
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• pp.169-183
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• 2009

This study has been conducted under the background of the high rocketed international oil price in the mid of the 2008 year. Korean logistics industry then suffered from a harsh labor strike which paralyzed temporarily Korean exports and imports activities mainly due to the rising motor fuel prices. The theme of this study started from the highly practical question: what would be the impact of the soaring crude oil price on the cost structure of the Korean logistics industry? For this practical question this study conducted an input-output analysis utilizing the 2003 year benchmark input-output table, published by the Bank of Korea in 2007.

• The Transactions of the Korea Information Processing Society
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• v.4 no.4
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• pp.1076-1088
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• 1997

Data repliciation techniques of distributed database a allocation methods occures to overhead to change together all repkicas for consistency maintenance at updates .In case of data migration horizontal or vertical fragment migration has caused to caused to increase data communication.In this paper we purpose batch proxessing method groups the associated items of table and stores temporary table assciated with file relication and migrations.This method increase the usagility of system buffer in distributed trancsaction processing with a number of data inputs and updates.After all,it improved the perform-ance of distributed transaction system by reducing disk I\O processing time and the cost of data cimmunication among local sites.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.6
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• pp.1146-1150
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• 2009

Cadmium telluride (CdTe) is one of the most attractive photovoltaic materials due to its low cost, high efficiency and stable performance in physical, optical and electronic properties. Few researches on the influences of uniform surface on the photovoltaic characteristics in large-area CdTe solar cell were not reported. As the preceding study of the effects of thickness-uniformity on the photovoltaic characteristics for the large-area CdTe thin film solar cell, chemical mechanical polishing (CMP) process was investigated for an enhancement of thickness-uniformity. Removal rate of CdTe thin film was 3160 nm/min of the maximum value at the 200 $gf/cm^2$ of down force (pressure) and 60 rpm of table speed (velocity). The removal rate of CdTe thin film was more affected by the down force than the table speed which is the two main factors directly influencing on the removal rate in CMP process. RMS roughness and peak-to-valley roughness of CdTe thin film after CMP process were improved to 96.68% and 85.55%, respectively. The optimum process condition was estimated by 100 $gf/cm^2$ of down force and 60 rpm of table speed with the consideration of good removal uniformity about 5.0% as well as excellent surface roughness for the large-area CdTe solar cell.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.9
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• pp.724-733
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• 2003

Generally, dividers have been designed to use iteration, but recently the research on the pipelined divider is underway. It is a difficult point in the known pipelined division unit that a large lookup table is required. In this paper, the cost-effective pipelined divider is proposed, that needs a lookup table smaller than that of the other pipelined divider. The latency of the proposed divider is 3 cycles. We obtain a 30% reduced area than that of P. Hung.

• Journal of the Korea Society of Computer and Information
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• v.3 no.4
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• pp.49-54
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• 1998

AS it takes a considerable time for database operations for processing the condition part of active rule, the operations have an important effect on the efficiency of active database system. The processing time of operations should be minimized in order to improve the efficiency of system. The previous works are limited to basic database operations and the partial aggregate functions. In this paper, the processing technique using the structuralization and the state table of relations is suggested. The processing time for basic database operations can be reduced with the structuralization of relations to classification tree and the introduction of deletion information table. With the introduction of binary search tree and relation state table, the aggregate function which has a big of processing cost can be processed effectively and the function of the active database system can be maximized.