• Transactions of the Korean Society of Automotive Engineers
• /
• v.23 no.6
• /
• pp.591-600
• /
• 2015

The efficiency of a powertrain system of hybrid vehicle is highly dependent on the design and control of the hybrid powertrain system. In other words, the optimal design of the powertrain systems is coupled with optimal control of the powertrain system. Therefore, the solution of an optimal design problem for hybrid vehicles is computationally and timely very expensive. For example, dynamic programming, which is a recursive optimization method, is usually used to evaluate the best fuel economy of certain hybrid vehicle design, and, thus, the evaluation takes tens of minutes to several hours. This research aims to accelerate the speed of efficiency evaluation of hybrid vehicles. We suggest a mathematical treat and a methodological treat to reduce the computational load. The mathematical treat is that the dynamics of system is discretized with sparse sampling time without loss of energy balance. The methodological treat is that the efficiency of the hybrid vehicle is inferred by characteristic loss evaluation that is computationally inexpensive. With the suggested methodology, evaluating a design candidate of hybrid powertrain system is taken few minutes, which was taken several hours when dynamic programming is used.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.42 no.2
• /
• pp.78-85
• /
• 2019

High variance observed in the measurement system can cause high process variation that can affect process capability badly. Therefore, measurement system analysis is closely related to process capability analysis. Generally, the evaluation for measurement system and process variance is performed separately in the industry. That is, the measurement system analysis is implemented before process monitoring, process capability and process performance analysis even though these analyses are closely related. This paper presents the effective concurrent evaluation procedure for measurement system analysis and process capability analysis using the table that contains Process Performance (Pp), Gage Repeatability & Reproducibility (%R&R) and Number of Distinct Categories (NDC). Furthermore, the long-term process capability index (Pp), which takes into account both gage variance and process variance, is used instead of the short-term process capability (Cp) considering only process variance. The long-term capability index can reflect well the relationship between the measurement system and process capability. The quality measurement and improvement guidelines by region scale are also described in detail. In conclusion, this research proposes the procedure that can execute the measurement system analysis and process capability analysis at the same time. The proposed procedure can contribute to reduction of the measurement staff's effort and to improvement of accurate evaluation.

• Korean Journal of Veterinary Service
• /
• v.43 no.4
• /
• pp.267-271
• /
• 2020

The emergence of highly contagious viral diseases of livestock and poultry such as foot-and-mouth disease (FMD), African swine fever (ASF) and highly pathogenic influenza (HPAI) have necessitated the formulation of policies and regulatory frameworks for preventing ingress of exotic diseases and controlling dissemination of endemic diseases within the country. The disease control ratings to manage contagious livestock disease in farms have not being widely used because the evaluation parameters were not being considered inappropriate. The purpose of this study was to reinforce the validity of the parameters for evaluation factors and the objectivity of the scoring criteria in the application of the current disease management rating system. The diseases subject to intensive management were improved by reflecting farm situation. For the evaluation based on the disease grading system of farms, the diseases subject to intensive management were realized, the list of diseases for evaluating the vaccination rate was revised, and the quarantine and sanitation management standards were revised. The effectiveness of the improved livestock disease management system was confirmed through the application of actual pig farms. Therefore, this system will be used as a means to evaluation the biosecurity at the farm units. Through this, it will contribute to establish effective biosecurity measures for each farm by improving and supplementing the present disease grading system.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.26 no.1
• /
• pp.1-11
• /
• 2022

In this study, the seismic performance of a two-story unreinforced masonry (URM) building was assessed following the linear and nonlinear static procedures specified in the seismic evaluation guideline of existing buildings. First, the provisions to assess failure modes and shear strengths of URM walls and wall piers were reviewed. Then, a two-story URM building was assessed by the linear static procedure using m-factors. The results showed that the walls and wall piers with aspect ratios h_e // (i.e., effective height-to-length ratio) > 1.5 were unsafe due to rocking or toe crushing, whereas the walls with h_e // ≤ 1.5 and governed by bed-joint sliding mainly were safe. Axial stresses and shear forces acted upon individual masonry walls, and wall piers differed depending on whether the openings were modeled. The masonry building was reevaluated according to the nonlinear static procedure for a more refined assessment. Based on the linear and nonlinear assessment results, considerations of seismic evaluation for low-rise masonry buildings were given with a focus on the effects of openings.

• Journal of Engineering Education Research
• /
• v.26 no.6
• /
• pp.30-39
• /
• 2023

This study was conducted with analyzing the perceptions of universities and industry regarding need analysis, curriculum design-implementation-outcomes, and the educational environment of the university evaluation institution from an industry perspective. First, as a result of analyzing the importance and implementation level of needs analysis, universities and industries recognized 'industrial trends in related fields' as the most important, but both groups perceived the implementation level to be significantly low. Second, as a result of analyzing the importance of implementing a curriculum based on industry needs, there was a difference in that universities recognized the 'adequacy of curriculum implementation based on industrial needs' and industries recognized the 'field training participation rate' as the most important. Third, as a result of analyzing the importance of curriculum outcomes based on industrial needs, it was found that both groups recognized 'field connection of major curriculum' as the most important. Fourth, as a result of analyzing the importance of the industry-university cooperative educational environment, it was found that both groups recognized 'construction and operation of experimental.practice educational facilities and infrastructure' as the most important. In short, the results of this study are expected to resolve the problem of mismatch between universities and industry in terms of talent development and education, and contribute to the effective implementation of the university evaluation institution from an industry perspective.

• The Journal of Health Technology Assessment
• /
• v.6 no.2
• /
• pp.148-155
• /
• 2018

Objectives: Rotavirus is one of the main causes of severe diarrhea in children under five. Two types of rotavirus vaccines [$Rotarix^{(R)}$ (RV1) and $Rotateq^{(R)}$ (RV5)] have been introduced and its administration was optional in South Korea. A systematic review (SR) on economic evaluation (EE) of RV was conducted to examine whether the introduction of rotavirus vaccine to national vaccine program (NIP) is cost-effective. Methods: Previous SR studies of EE for RV were searched in August 2017 through databases such as MEDLINE and EMBASE. Additional search was performed to include literatures published after or unincluded in the previous SR studies. Among the 11 SR studies identified, 2 studies were reviewed via inclusion/exclusion criteria. A previous SR study including 104 original articles was selected by A MeaSurement Tool to Assess systematic Reviews. Among the 36 original articles identified through additional search, 10 were selected, resulting in 114 studies included in our analysis. Results: RV1-only, RV5-only, and evaluating-both studies account for about 44%, 22%, and 33%, respectively. Among RV1-only, RV5-only, or evaluating-both studies, 90%, 64%, or 68% of the studies concluded RV as being cost-effective, respectively. RV5-only studies were usually executed in high-income countries (68%), whereas RV1-only studies were executed mostly in lower (32%) and upper (26%) middle-income countries. When classifying studies by their funding sources, RV1-only studies (82%; 28 of 34 studies specifying funding sources) were chiefly supported by non-profit organization, and 100% of these studies were concluded as being cost-effective. RV5-only studies were mostly supported by profit organization (68%; 13 of 19 studies specifying sources), and 92% of these studies concluded as being cost-effective. Conclusion: By reviewing global EE studies for RV, we have learned that about 70% of these studies was shown to be cost-effective and RV1 appeared to be more cost-effective than RV5.

• New & Renewable Energy
• /
• v.5 no.3
• /
• pp.32-39
• /
• 2009

The Samcheonpo ocean small hydropower plant (SHP) has a special feature of using marginal hydraulic head of circulating water system of fossil fuel power plant as a power source and having the characteristics of general hydropower generation and tidal power generation as well. Also, it contributes to reducing green house gases and developing clean energy source by recycling circulating water energy otherwise dissipated into the ocean. The efficiency of small hydropower plant is directly affected by effective head and flow rate of discharged water. Therefore, the efficiency characteristics of ocean hydropower plant are analyzed with the variation of water level and flow rate of discharged water, which is based on the accumulated operation data of the Samcheonpo hydropower plant. After the start of small hydropower plant operation, definite rise of water level was observed. As a result of flow pattern change from free flow to submerged flow, the instability of water surface in overall open channel is increased but it doesn't reach the extent of overflowing channel or having an effect on circulation system. Performance evaluation result shows that the generating power and efficiency of small hydropower exceeds design requirements in all conditions. Analysis results of CWP's water flow rate verify that the amount of flowing water is measured less and the highest efficiency of small hydropower plant is achieved when the effective head has its maximum value. In conclusion, efficiency curve derived from water flow rate considering tidal level shows the best fitting result with design criteria curve and it is verified that overall efficiency of hydropower system is satisfactory.

• Journal of the Korean Society of Laryngology, Phoniatrics and Logopedics
• /
• v.27 no.1
• /
• pp.45-50
• /
• 2016

Background and Objectives : This study aims to conduct post-voice therapy to patients with unilateral vocal fold paralysis for vocal improvement, motility recovery and analyze the results. Materials and Methods : Voice therapy was conducted to 13 patients who had shown response to voice therapy amongst 98 patients diagnosed with unilateral vocal fold paralysis. In order to be able compare before and after perceptual, acoustic and aerodynamic evaluations were conducted after voice therapy. Also, by using dysphagia checklist, we have verified whether if the patient had dysphagia prior to voice therapy. The therapy was conducted by improving the larynx movement and glottal contact, whilst removing hypertension of the supraglottic. Results : All 13 patients who underwent voice therapy had shown improvements that are statistically significant from 4 scales excluding the S scale from auditory perception evaluation (p<0.05), with enhanced glottal contact. In acoustic evaluation, Jitter, Shimmer and NHR had shown significant improvement after voice therapy. MPT was also notably improved among aerodynamical evaluation (p<0.001). All 11 patients had with dysphagia prior to voice therapy reported to have improved swallowing functions. Conclusion : Application of adequate voice therapy to patients with unilateral vocal fold paralysis, is an effective method that might be employed in the initial phase. Especially, the voice therapy proposed in this study is expected to be useful for patients in hypertension status due to secondary compensation after initial paralysis, since it focuses on improving vocal symptoms in a calm state with the supraglottis sufficiently relaxed. Also, the therapy is expected to be effective for improving swallowing functions.

• Journal of Korean Society on Water Environment
• /
• v.26 no.6
• /
• pp.903-909
• /
• 2010

The purpose of this study was evaluated on the applicability of Load Duration Curve Method (LDC Method) using HSPF watershed model and sampling data for efficient TMDLs in Korea. The LDC Method was used for assessment pollutant characteristics in watershed and water quality variation in each water flow level. Load Duration Curve is applied for judge the level of impaired water-body and can be estimated the impaired level by pollutant, such as BOD, T-N, and T-P in this study depending on variation of stream flow. As a result, BOD, T-P was usually exceed the standard value at low flow and dry hydrologic period. Improvement of effluent concentration from WWTP and riparian buffer protection zone are effective to improve the water quality. T-N showed the worst condition at mid-range hydrologic period and moist hydrologic period. Therefore, soil erosion control program and BMPs for non-point source pollution control is effective for recovery the water quality, which can be useful method for management of water quality in the plan of recovery water quality spontaneously. Applicability of LDC Method was evaluated in the Nakbon A watershed. However, we need to consider more detailed and accumulated data set such as accurate GIS data and detail pollution data, and WWTP discharge water quality data for accurate evaluation of watershed. Overall, The LDC Method is adequate for evaluation of watersheds characteristics, and its application is recommended for watershed management and TMDL Implementation.

• Journal of Korean Neurosurgical Society
• /
• v.45 no.4
• /
• pp.219-223
• /
• 2009

Objective : Functional magnetic resonance imaging (fMRI) is frequently used to localize language areas in a non-invasive manner. Various paradigms for presurgical localization of language areas have been developed, but a systematic quantitative evaluation of the efficiency of those paradigms has not been performed. In the present study, the authors analyzed different language paradigms to see which paradigm is most efficient in localizing frontal language areas. Methods : Five men and five women with no neurological deficits participated (mean age, 24 years) in this study. All volunteers were right-handed. Each subject performed 4 tasks, including fixation (Fix), sentence reading (SRI. pseudoword reading (PR), and word generation (WG). Fixation and pseudoword reading were used as contrasts. The functional area was defined as the area(s) with a t-value of more than 3.92 in fMRI with different tasks. To apply an anatomical constraint, we used a brain atlas mapping system, which is available in AFNI, to define the anatomical frontal language area. The numbers of voxels in overlapped area between anatomical and functional area were individually counted in the frontal expressive language area. Results : Of the various combinations, the word generation task was most effective in delineating the frontal expressive language area when fixation was used as a contrast (p<0.05). The sensitivity of this test for localizing Broca's area was 81 % and specificity was 70%. Conclusion : Word generation versus fixation could effectively and reliably delineate the frontal language area. A customized effective paradigm should be analyzed in order to evaluate various language functions.