• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.525-526
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• 2011

• The Mathematical Education
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• v.29 no.1
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• pp.21-34
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• 1990

This is a study on an instruction of estimation for error correction in the calculation with a computer or a calculator. The aim of this study is to survey a new aspect of calaulation teaching and the teaching strategy of estimation and finally to frame a new curriculum model of estimation instruction. This research required a year and the outcomes of the research can be listed as follows: 1. Social utilities of estimation were made clear, and a new trend of calculation teaching related to estimation instruction was shown. 2. The definition of estimation was given and actual examples of conducting an estimation among pupils in lower grades were given for them to have abundant experiences. 3. The ways of finding estimating values in fraction and decimal fraction were presented for the pupils to be able to conduct an estimation. 4. The following contents were given as a basic strategy for estimation. 1) Front-end strategy 2) Clustering strategy 3) Rounding strategy 4) Compatible numbers strategy 5) Special numbers strategy 5. In an instuction of estimation the meaning, method. and process of calculation and calculating algorithm were reviewed for the cultivation of children's creativity through promoting their basic skill, mathematical thinking and problem-solving ability. 6. The following contents were also covered as an estimation strategy for measurement 1) Calculating the sense of quantity on the size of unit. 2) Estimating the total quantity by frequent repetition of unit quantity. 3) Estimating the length and the volume by weighing. 4) Estimating unknown quantity based on the quatity already known. 5) Estimating the area by means of equivalent area transformation. 7. The ways of instructing mental computation were presented. 8. Reviews were made on the curricular and the textbook contents concerning estimation instructions both in Korea and Japan. and a new model of curriculum was devised with reference to estimation instruction data of the United States.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.315-320
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• 2009

Thermoeconomics or exergoeconomics can be classified into the three fields of cost estimating, cost optimization, and internal cost analysis. The objective of cost estimating is to estimate each unit cost of product and allocate each cost flow of product such as electricity or hot water. The objective of optimization is to minimize the input costs of capital and energy resource or maximize the output costs of products under the given constraints. The objective of internal cost analysis is to find out the cost formation process and calculate the amount of cost flow at each state, each component, and overall system. In this study, a new thermoeconomic methodology was proposed in the three fields. The proposed methodology is very simple and obvious. That is, the equation is only each one, and there are no auxiliary equations. Any energy including enthalpy and exergy can be applied and evaluated by this equation. As a new field, the cost allocation methodology on cool air or hot air produced from an air-condition system was proposed. Extending this concept, the proposed methodology can be applied to any complex system.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.791-800
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• 2013

Needs for developing a better way of cost estimating process for public construction projects have been widely recognized. Those needs are mainly from the early phases of the project through the construction life cycle due to the its importance to the control process. In contrast to the traditional estimating method based on unit-price references, this research utilized this following process. The first step is analyzing the real cost data from actual cost activities (2000~2010) about the statement of P.S.C(Prestressed Concrete) Box Girder Bridge. The collected data was broken into four categories based on technical construction methods such as I.L.M(Incremental Launching Method), M.S.S(Movable Scaffolding System), F.S.M(Full Staging Method), and F.C.M(Free Cantilever Method). The second, actual design documents including the actual cost estimating documents, drawings and specifications were carefully reviewed to cluster the cost itemized statement from four categories. It was also attempted to seek the proper breakdown of standard works that are responsible for more than 95 percentage in each categories in terms of its cost. The third, this research comes up the index for standard unit materials and unit price of standard work and develops the approximate estimating model applying for the specification(length and breadth of bridges) per square area that the user takes as well as suggests the practical application plan within the original time alloted.

• Korean Institute of Interior Design Journal
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• no.23
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• pp.68-73
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• 2000

The purpose of this research is to develop interior construction cost-estimating system at the early stage of the project. Though general construction estimates are typically in quantitative, interior construction should be in rather qualitative. Therefore, design-concerned cost-estimating methods should be developed to manage interior projects from the early statge. 30 estimates of VIP-Zone interior projects, were examined to develop the general type of composition and material classification. The cost has been classified by construction parts such as wall, ceiling, floor, and doors & windows and their treatments. The composition and material related estimating system (CMRES) was consisted of the unit average costs of classification and the variation coefficients. The CMRESS was verified by the case study, and the results sowed that the difference between the actual estimate and the CMRES was competitively confident.

• Journal of the Korea Institute of Building Construction
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• v.5 no.2 s.16
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• pp.147-152
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• 2005

The purpose of this study is to present a rational approach for estimating the unit price and the amounts of sealing materials of the sealing works. This approach, considering field conditions and sealing materials' characteristics, can optimize the cost of the sealing works as well as that of maintenance. For the study, 10 case buildings for 3 years, built by middle size construction firm, were studied in order to investigate the unit price and the amounts of sealing materials.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.169-171
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• 2012

Although work-efficiency of construction machinery is a critical factor for estimating its workable-quantity per unit time, the coefficient figure table presented in the Poom-Sam that is used for Construction Cost Estimation of public sectors in Korea is very subjective for practical usage. In order to suggest objective work-coefficient table for a Tub Grinder, domestic and overseas documentary records were investigated and on-going construction sites were also visited. The research found that the table can be revised by means of detailing down by several factors. The research will be the foundation for applying the rapid development of Construction Equipment and technology to the appropriate cost estimations and the ground work of related studies.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.14 no.1
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• pp.30-37
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• 1989

The MUSIC(MUltiple SIgnal Characterization)algorithm has been extenced to the UCERSS(Unit Circle Eigendecomposition Rational Signal Subspace) by taking eigendecimposition on the unit circle in order to estimate incident angles of multiple wide band signals. The purpose of this paper is to presetn SSB-UCERSS(Signal Subspace Based UCERSS) and SS-UCERSS(Spatially Smoothed UCERSS) estimating the incident angles of multiple side band signals in multipath(coherent signals) environments. Computer simulation results indicate that SSB-UCERSS yields the best result, while the SS-UCERSS performs better than the UCERTSS in a multipath environment.

• International Journal of Highway Engineering
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• v.17 no.2
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• pp.143-150
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• 2015

PURPOSES : The authors set out to estimate the related carbon emissions, energy use, and costs of the national freeways and highways in Korea. To achieve this goal, a macro-level methodology for estimating those amounts by road type, road structure type, and road life cycle was developed. METHODS : The carbon emissions, energy use, and costs associated with roads vary according to the road type, road structure type, and road life cycle. Therefore, in this study, the road type, road structure type, and road life cycle were classified into two or three categories based on criteria determined by the authors. The unit amounts of carbon emissions and energy use per unit road length by classification were estimated using data gathered from actual road samples. The unit amounts of cost per unit road length by classification were acquired from the standard cost values provided in the 2013 road business manual. The total carbon emissions, energy use, and cost of the national freeways and highways were calculated by multiplying the road length by the corresponding unit amounts. RESULTS: The total carbon emissions, energy use, and costs associated with the national freeways and highways in Korea were estimated by applying the estimated unit amounts and the developed method. CONCLUSIONS: The developed method can be employed in the road planning and design stage when decision makers need to consider the impact of road construction from an environmental and economic point of view.

• Transportation Technology and Policy
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• v.8 no.1
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• pp.15-27
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• 2011