• Journal of Industrial and Engineering Chemistry
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• v.67
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• pp.132-139
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• 2018

A cost-effective preparation method is proposed to prepare nanoporous alumina (NA) using aluminum chloride as a precursor with a lower cost than aluminum butoxide. In addition, the surfactant template was replaced with magnesium stearate, which has a lower unit cost in stearate acid. The adsorption isotherm test for the CO gas was carried out to compare the adsorption performance of the NA adsorbents prepared using post-hydrolysis (NA) and cost-effective precipitation (C-NA). In addition, C-NA exhibited a similar uptake capacity as NA, and the maximum uptake capacity of Pd/C-NA increased 1.3 times via Pd nanodots loading.

• International conference on construction engineering and project management
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• 2013.01a
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• pp.488-493
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• 2013

Accurate initial cost estimates are essential to effective management of construction projects where many decisions are made in the course of project management by referencing the estimates. In practice, the initial estimates are frequently derived from historical actual cost data, for which standard distribution-based techniques are widely applied in the construction industry to account for risk associated with the estimates. This approach assumes the same probability distribution of estimate errors for any selected estimates. This assumption, however, is not always satisfied. In order to account for the probabilistic nature of estimate errors, an alternative method for measuring the risk associated with a selected initial estimate is developed by applying the Bayesian probability approach. An application example include demonstrates how the method is implemented. A hypothesis test is conducted to reveal the robustness of the Bayesian probability model. The method is envisioned to effectively complement cost estimating methods that are currently in use by providing benefits as follows: (1) it effectively accounts for the probabilistic nature of errors in estimates; (2) it is easy to implement by using historical estimates and actual costs that are readily available in most construction companies; and (3) it minimizes subjective judgment by using quantitative data only.

• The Journal of the Korea Contents Association
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• v.16 no.9
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• pp.376-385
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• 2016

The purpose of this study is to establish the basis of cash wages calculation of the extra cost for the local characteristics by analyzing the local differences of the extra costs of households with the disabled. It was analyzed by comparing the average population by combining the '2011 Survey on disability' and the '2011 municipal budget with disabilities' to analyze the local difference of the extra costs. The highest region of the extra costs was Incheon, and the highest region of the extra cost preservation was Seoul. The highest region of the disabled budget rate was Daejeon, and the highest region of the disabled per capita budget was Jeju. According to a independent two sample t-test, the disabled budget rate and per capita budget of the highest regions of the extra cost preservation were higher than the lowest regions of the extra cost preservation. With policy proposals first, the increase in cash wages of the extra cost for the local characteristics second, the increase the disabled budget and per capita budget of the local governments third, the plan for a decrease of the extra costs according to the extra cost items of local.

• Journal of Applied Reliability
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• v.12 no.3
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• pp.131-138
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• 2012

A design of reliability qualification test based on performance distribution is developed. In general, the performance of an item degrades as the time goes by and the failure of an item occurs when the performance degradation reaches the pre-determined critical level. This article considers the reliability qualification test based on a more tightened critical value at the earlier stage to reduce the evaluation testing time and cost. A numerical example is provided to illustrate how to use the developed reliability qualification test.

• Journal of Applied Reliability
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• v.15 no.2
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• pp.84-89
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• 2015

Accelerated life tests are widely used to evaluate the product reliability within a resonable amount of time and cost. This article provides literature review about accelerated life test plans between 2006~2015. The literature on planning accelerated life tests are reviewed with respect to the test scenario, assumed accelerated model and estimation method and optimization criteria. Finally, recommendations for the future research are presented.

• Journal of the Korean Institute of Telematics and Electronics
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• v.24 no.3
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• pp.535-540
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• 1987

This paper proposes a circuit partitioning method and a multifunctional BILBO which can perform the multimodule test in the case of testing VLSI circuits. By using these circuit partitioning method and multifunctional BILBO, test time and cost can be reduced greatly by performing the pipeline test method. And the quantity of circuit that shold be added for testing is also reduced in half by interposing only one BILBO between each module. Also, we confirmed that the multifunctional BILBO proposed here has high error detection capability by analyzing error detection capability of this multifunctional BILBO in mathematics.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.677-684
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• 2008

The paper provides an approximate cost estimating model that can be used for tunnel. Based on the previous study analyzed critical factors that have impact on tunnel construction cost, this paper establishes a cost variance index table that reflects the cost impacts due to the change of the critical cost factors. An estimating procedure is described utilizing the index table. For the verification of the suggested model, the comparison of the estimated construction cost with real project cost is performed. The estimated results range from 95%~111% of the real project costs. As an approximate tunnel cost estimating model, the model can be utilized to quickly estimate tunnel construction costs based on the conceptual information at the planning stage and to efficiently make a decision on design alternatives.

• The Journal of the Korea Contents Association
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• v.18 no.4
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• pp.664-676
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• 2018

This study used raw data from the Korea Medical Panel Survey for 2014 to analyze the factors affecting the cost of medicine expenditure. A total of 3,107 people with medical expenses were selected for the final analysis. Analysis methods were frequency analysis, crossover analysis, regression analysis and t-test. The significance level of all tests was p = .05. The prescription cost was 72.4%, the minimum cost was 84 won, the maximum cost was 270,653 won, and the highest amount was 'over 3,000 won~less than 10,000 won' (31.7%). The general pharmaceuticals cost was 81.8%, the minimum cost was 800 won, the maximum cost was 2,718,000 won, and the highest amount was 'less than 20,000 won' (31.4%). The herbal medicine cost was 9.4%, the minimum cost was 4,000 won, the maximum cost was 2,700,000 won, and the highest amount was 'over 100,000 won' (37.8%). The medicines expenditure was the maximum cost was 2,760,093 won, and the highest amount was 'over 100,000 won' (27.0%). Factors affecting medicine expenditure were gender, marital status, income quintile, easement, and subjective health status.

• Korean Journal of Construction Engineering and Management
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• v.16 no.2
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• pp.46-53
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• 2015

Electrical construction cost index is composed of the cost of albor and material. The producer price index is used to the cost of material. The Bank of Korea restructured the formation method and the basic period of the producer price index in 2013. Because fixed-weighted method can't faithfully reflect industrial structure changes. The weighted value and price index of fixed-weighted method is fixed on the basicp eriod. Electrical construction cost index is changed from fixed-weighted method to chain-weighted method in september 2014, because of these on the need. But the change of organization in formation method changes the weighted value. So there is the need of analysis about the statistical continuity of electrical construction cost index. This study is focused on the time series analysis between fixed-weighted and chain-weighted electrical construction cost index. We uses unit root test, cointegration test, regression analysis of long and short term equation, fitness for the estimation of static forecast as time series analysis. We verify that chain-weighted electrical construction cost index can be replaced to fixed-weighted construction cost index accounting analyses result. So users of it recognize that chain-weighted electrical construction cost index has statistical continuity.

• Geomechanics and Engineering
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• v.14 no.6
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• pp.533-544
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• 2018

The importance of using materials cost effectively to enhance the strength and reduce the cost, and weight of earth fill materials in geotechnical engineering led researchers to seek for modifying the soil properties by adding proper additives. Lightweight fill materials made of soil, binder, water, and Expanded polystyrene (EPS) beads are increasingly being used in geotechnical practices. This paper primarily investigates the behavior of sandy soil, modified by EPS particles. Besides, the mechanical properties of blending sand, EPS and the binder material such as fly ash and cement were examined in different mixing ratios using a number of various laboratory studies including the Modified Standard Proctor (MSP) test, the Unconfined Compressive Strength (UCS) test, the California Bearing Ratio (CBR) test and the Direct Shear test (DST). According to the results, an increase of 0.1% of EPS results in a reduction of the density of the mixture for 10%, as well as making the mixture more ductile rather than brittle. Moreover, the compressive strength, CBR value and shear strength parameters of the mixture decreases by an increase of the EPS beads, a trend on the contrary to the increase of cement and fly ash content.