• International Journal of Automotive Technology
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• v.7 no.3
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• pp.353-360
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• 2006

The nominal structural stress calculation method proposed by Radaj has included some problems as follows: (a) How the value of the diameter D is decided in the method; (b) It is not possible to estimate nominal structural stress of the spot welded joints with the balanced sheet in-plane load that no general loads are obtained by FE shell analysis. In this paper, the new method for calculating nominal structural stress was proposed to solve above-mentioned problems. The proposed method calculates the nominal structural stress through the circular plate theory in theory of elasticity. This theoretical analysis uses not only general loads but also nodal displacements around spot welding provided by FE shell analysis as boundary condition. Fatigue test data of various spot-welded joints could be arranged in a narrow bandwidth on S-N chart using the nominal structural stresses calculated by proposed method. The fatigue life prediction method using the proposed method for calculating nominal structural stress is useful for the prior evaluation technique that can predict the fatigue life of spot welding by CAE.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.31 no.3
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• pp.274-285
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• 2021

Objectives: The question of whether the level of fees paid to working environment measurement agencies is appropriate has long been a matter of concern to the government. In addition, measurement institutions express dissatisfaction with their level of compensation, which has a great influence on the evaluation of a subject's policy. This study is intended to find a way to appropriately calculate working environment measurement fees. Methods: We looked at the principle of fee determination as a basic theory of fee calculation used in fee calculation, the legal and academic aspects of the general method of fee calculation, and government cost calculation standards. Furthermore, we reviewed the research methods applied so far to derive a method of calculating fees appropriate for this environment. Results: The working environment measurement environment is different from other commission calculation environments. The other environment is to appropriately calculate the service price provided by a monopoly public enterprise, while the situation is to appropriately calculate the fees provided by competitive private enterprises. Therefore, the service delivery environment and the delivery entity are different. In this case, the appropriate method of calculating service fees would be competitive pricing. There have also been many problems under the method of calculation by service cost. Conclusions: First, the working environment measurement fee requires an accounting correction of endogenous variables. Second, the theory of calculating fees appropriate for this situation is appropriate for competitive pricing that applies to private competitors. Third, the government should make efforts to make the service supply market a fully competitive market while ensuring that the service fee level is determined at the marginal cost level. Fourth, economically, research on marginal cost levels is needed.

• Korean Journal of Construction Engineering and Management
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• v.22 no.3
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• pp.12-20
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• 2021

In order to secure construction quality and safety and prevent cost disputes, the importance of calculating 'the appropriate construction period' has recently emerged. It is necessary to analyze a considerable amount of historical data to establish the standard for calculating the construction period. However, many experts are raising questions about the use of past data due to changes in the construction business environment, such as shortening working hours, reinforcing quality regulations, and changing climate conditions. In addition, the possibility of errors increases when calculating a uniform construction period using historical statistics because the work order and productivity are very diverse according to construction conditions. Therefore, through this study, a new solution to change from the method of analyzing past data to the method of reviewing current production data through an active 'transformation of thoughts' was proposed through this study. In other words, the process of reviewing and calculating 'the appropriate construction period' was institutionalized by introducing 'process management experts' and 'construction experts by type of construction' in the design stage.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.28 no.2
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• pp.76-83
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• 2014

This paper deals with the numerical method of calculating the frequency-dependent impedances of grounding electrodes. The proposed electromagnetic field approach is based on the solutions to Maxwell's equations obtained from the method of moment in the frequency domain. In order to evaluate the quality of the proposed simulation method, the frequency-dependent impedances of horizontally-buried ground electrodes were presented. The program for calculating the current distributions and impedances of grounding electrodes was implemented in MATLAB. The grounding impedances of two 10m and 50m long horizontal ground electrodes were measured and simulated in the frequency range from 100Hz to 10MHz for easy analysis and comparison. Also the simulated results were compared with those calculated from a sophisticated computer program CDEGS (HIFREQ module). As a result, the resultant results of frequency-dependent impedances obtained by using the numerical simulation method proposed in this work are in good agreement with experimental data. The validity of the approach techniques was confirmed.

• 한국HCI학회:학술대회논문집
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• 2007.02a
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• pp.268-273
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• 2007

In this paper, we present effective methods for automatic music recommendation system which automatically recommend music by signal processing technology. Conventional music recommendation system use users’ music downloading pattern, but the method does not consider acoustic characteristics of music. Sometimes, similarities between music are used to find similar music for recommendation in some method. However, the feature used for calculating similarities is not highly related to music characteristics at the system. Thus, our proposed method use high-level music characteristics such as rhythm pattern, timbre characteristics, and the lyrics. In addition, our proposed method store features of music, which individuals queried, to recommend music based on individual taste. Experiments show the proposed method find similar music more effectively than a conventional method. The experimental results also show that the proposed method could be used for real-time application since the processing time for calculating similarities between music, and recommending music are fast enough to be applicable for commercial purpose.

• Structural Engineering and Mechanics
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• v.43 no.3
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• pp.321-336
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• 2012

As an improvement on the isoparametric element method, the derivation presented in this paper is close to that done by Wang (1990) for the 2-D finite element. We extend this idea to solve 3-D crack problems in this paper. A new displacement modelling is constructed with local solutions of three-dimensional cracks and a quasi-compatible isoparametric element for three-dimensional fracture mechanics analysis is presented. The stress intensity factors can be solved directly by means of the present method without any post-processing. A new method for calculating the stress intensity factors of three-dimensional cracks with complex geometries and loads is obtained. Numerical examples are given to demonstrate the validity of the present method. The accuracy of the results obtained by the proposed element is demonstrated by solving several crack problems. The results illustrate that this method not only saves much calculating time but also increases the accuracy of solutions. Because this quasi-compatible finite element of 3-D cracks contains any singularities and easily meets the requirement of compatibility, it can be easily implemented and incorporated into existing finite element codes.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.306-314
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• 2015

This paper examines the difference in the value of the nuclear fuel cycle cost calculated by the deterministic and probabilistic methods on the basis of an equilibrium model. Calculating using the deterministic method, the direct disposal cost and Pyro-SFR (sodium-cooled fast reactor) nuclear fuel cycle cost, including the reactor cost, were found to be 66.41 mills/kWh and 77.82 mills/kWh, respectively (1 mill = one thousand of a dollar, i.e., $10^{-3}$ $). This is because the cost of SFR is considerably expensive. Calculating again using the probabilistic method, however, the direct disposal cost and Pyro-SFR nuclear fuel cycle cost, excluding the reactor cost, were found be 7.47 mills/kWh and 6.40 mills/kWh, respectively, on the basis of the most likely value. This is because the nuclear fuel cycle cost is significantly affected by the standard deviation and the mean of the unit cost that includes uncertainty. Thus, it is judged that not only the deterministic method, but also the probabilistic method, would also be necessary to evaluate the nuclear fuel cycle cost. By analyzing the sensitivity of the unit cost in each phase of the nuclear fuel cycle, it was found that the uranium unit price is the most influential factor in determining nuclear fuel cycle costs.

• The KIPS Transactions:PartB
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• v.16B no.1
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• pp.71-78
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• 2009

For more effective index extraction and index weight determination, studies of extracting indices are carried out by using document content as well as structure. However, most of studies are concentrating in calculating the importance of context rather than that of XML tag. These conventional studies determine its importance from the aspect of common sense rather than verifying that through an objective experiment. This paper, for the automatic indexing by using the tag information of XML document that has taken its place as the standard for web document management, classifies major tags of constructing a paper according to its importance and calculates the term weight extracted from the tag of low weight. By using the weight obtained, this paper proposes a method of calculating the final weight while updating the term weight extracted from the tag of high weight. In order to determine more objective weight, this paper tests the tag that user considers as important and reflects it in calculating the weight by classifying its importance according to the result. Then by comparing with the search performance while using the index weight calculated by applying a method of determining existing tag importance, it verifies effectiveness of the index weight calculated by applying the method proposed in this paper.

• Journal of IKEEE
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• v.23 no.1
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• pp.188-192
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• 2019

As the contribution of the Energy Storage System (ESS) on the power system operations has increased, it is required to secure the reliability on the capacity of ESS and this needs to consider the outage rate in calculating the available capacity of ESS. However, the existing method of calculating the outage rate does not consider the configuration of ESS and this does not accurately calculate the available capacity of ESS. For this, this paper analyzes the structural characteristics of ESS in Korean power system and proposes a method to calculate the outage rate of ESS. Through the study cases adopting the Korea Electric Power Corporation (KEPCO) ESS for providing the frequency response service, the effectiveness of the proposed method verified.

• Journal of the Earthquake Engineering Society of Korea
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• v.23 no.3
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• pp.183-190
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• 2019

Recent changes in the construction method of piles to minimize noise, along with the development of high-strength reinforcement, have provided an economical high performance RC pile development to compensate for the disadvantages of existing PHC piles. In this study, a methodology for the development of cross - section details of high performance RC piles of various performances is presented by freely applying high strength steel and concrete. This study suggested a technique for calculating bending moments for a given axial force corresponding to the allowable crack widths and this can be used for serviceablity check. In calculating the design shear force, the existing design equation applicable to the rectangular or the I section was modified to be applicable to the hollow circular section. In particular, in the limit state design method, the shear force is calculated in proportion to the axial force, and the procedure for calculating PV diagram is established. Last, the section details are determined through PM diagrams that they have the similar flexural and axial-flexural performances of the PHC pile A, B and C types with a diameter of 500 mm. To facilitate the application of the selected standard sections to the practical tasks, the design PM diagram and design shear forces are proposed in accordance with the strength design method and limit state design method.