• International Journal of Railway
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• v.2 no.3
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• pp.124-126
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• 2009

Energy savings can be achieved with optimum energy consumptions, brake energy regeneration, efficient energy storage (onboard, line side), and primarily with light weight vehicles. Over the last few years, the rolling stock industry has experienced a marked increase in eco-awareness and needs for lower life cycle energy consumption costs. For rolling stock vehicle designers and engineers, weight has always been a critical design parameter. It is often specified directly or indirectly as contractual requirements. These requirements are usually expressed in terms of specified axle load limits, braking deceleration levels and/or demands for optimum energy consumptions. The contractual requirements for lower weights are becoming increasingly more stringent. Light weight vehicles with optimized strength to weight ratios are achievable through proven design processes. The primary driving processes consist of: $\bullet$ material selection to best contribute to the intended functionality and performance $\bullet$ design and design optimization to secure the intended functionality and performance $\bullet$ weight control processes to deliver the intended functionality and performance Aluminium has become the material of choice for modern light weight bodyshells. Steel sub-structures and in particular high strength steels are also used where high strength - high elongation characteristics out way the use of aluminium. With the improved characteristics and responses of composites against tire and smoke, small and large composite materials made components are also found in greater quantities in today's railway vehicles. Full scale hybrid composite rolling stock vehicles are being developed and tested. While an "overdesigned" bodyshell may be deemed as acceptable from a structural point of view, it can, in reality, be a weight saving missed opportunity. The conventional pass/fail structural criteria and existing passenger payload definitions promote conservative designs but they do not necessarily imply optimum lightweight designs. The weight to strength design optimization should be a fundamental design driving factor rather than a feeble post design activity. It should be more than a belated attempt to mitigate against contractual weight penalties. The weight control process must be rigorous, responsible, with achievable goals and above all must be integral to the design process. It should not be a mere tabulation of weights for the sole-purpose of predicting the axle loads and wheel balances compliance. The present paper explores and discusses the topics quoted above with a view to strengthen the recommendations and needs for the weight optimization by design approach as a pro-active design activity for the rolling stock industry at large.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.130-137
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• 2017

The purpose of this study is to provide a reasonable analytical method for the reinforced concrete beams which shows failure mode of shear and flexure-shear by proposing a modified formulation to consider the effect of shear deformation on the beam-column fiber element based on the flexibility method and a new constitutive law of inelastic shear response history for the section. A total of 6 specimens of reinforced concrete beams which is designed to cause shear failure before yielding longitudinal reinforcement to investigate the influence of the main experimental variables on the shear behavior characteristics and the analysis was performed by using a non-linear finite element analysis program (RCAHEST) applying the newly modified constitutive equation by the authors. The failure mode and the overall behavior characteristics until fracture are predicted appropriately for all specimens and the results are expected to be useful enough for the 3 - D analysis to carry out reliable results of large-scale and complicated structures in the future.

• Journal of the Korean association of regional geographers
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• v.15 no.6
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• pp.752-762
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• 2009

This paper aims to investigate the characteristics of location and business-services networks of venture firms in Daegu region. The regional venture firms are small scale and consist of mainly R&D investment and license new-technology in the category of soft-ware. Since the mid-1990's the firms that were founded by people with higher education and career experience seek diverse growth strategies. those firms concentrate in some regions of dalseo-gu and buk-gu. There are a few difference by types of firm-business, but, on the whole, the princepal location factors of venture firms are accessibility of research institute and university, easy information availability, and use of moderate land. In regard to networks with client firms, the venture firms determine whether to transfer. The result of the characteristics of networks between regional venture firms and business-service enterprises is as follows; the regional venture firms utilize small number of business-service enterprises and use mainly information processing and other computer operation related services and professional, scientific and technical services. In business-service be used by regional venture firms, the frequency of information processing and other computer operation related services, research and development, business support services is much, while the frequency of professional, scientific and technical services is little. Business-service enterprises are distributed mostly in Daegu region and are used owing to lack of technology and knowledge.

• Science of Emotion and Sensibility
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• v.12 no.2
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• pp.169-180
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• 2009

The present study have investigated the effect of the characteristics of stereoscopic images and viewing environment on visual fatigue. We manipulated the speed of stereo images with motion-in-depth and viewing distance, which were used as representative variables of the characteristics of stereo image and viewing environment, respectively. Visual fatigue was evaluated with use of a subjective questionnaire which is consisting of 5 different and independent factors: "Eye pain", "Visual stress," "Nauseousness", "Body stiffness", and "Blurriness". In general, when viewing time increased from 10 minutes to 20 and 40 minutes, observers felt severe visual fatigue. Among other factors, only the factor score of "Nauseousness" was significantly increased as the speed of object moving in depth became faster. When viewing distance was increased, the score of "Blurriness" was decreased. These results suggest that different kind of the visual fatigue might be induced depending on characteristics of the stereo images and viewing environment.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.1-13
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• 2014

Lithium ion batteries (LIBs) are the state-of-the-art technology among electrochemical energy storage and conversion cells, and are still considered the most attractive class of battery in the future due to their high specific energy density, high efficiency, and long cycle life. Rapid development of power-hungry commercial electronics and large-scale energy storage applications (e.g. off-peak electrical energy storage), however, requires novel anode materials that have higher energy densities to replace conventional graphite electrodes. Germanium (Ge) and silicon (Si) are thought to be ideal prospect candidates for next generation LIB anodes due to their extremely high theoretical energy capacities. For instance, Ge offers relatively lower volume change during cycling, better Li insertion/extraction kinetics, and higher electronic conductivity than Si. In this focused review, we briefly describe the basic concepts of LIBs and then look at the characteristics of ideal anode materials that can provide greatly improved electrochemical performance, including high capacity, better cycling behavior, and rate capability. We then discuss how, in the future, Ge anode materials (Ge and Ge oxides, Ge-carbon composites, and other Ge-based composites) could increase the capacity of today's Li batteries. In recent years, considerable efforts have been made to fulfill the requirements of excellent anode materials, especially using these materials at the nanoscale. This article shall serve as a handy reference, as well as starting point, for future research related to high capacity LIB anodes, especially based on semiconductor Ge and Si.

• Journal of Nutrition and Health
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• v.38 no.10
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• pp.880-894
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• 2005

The purposes of this study were to a) measure the IC identified of CFMC (contract foodservice management company) ,b) examine IC circumstance of CFMC, c) evaluate practically IC measurement tool of CFMC, and d) present information for selecting an adequate CFMC to clients. The questionnaires of IC measurement were handed out to 108 CFMCs, there composing of main office employees, foodservice managers, customers, and clients of 207 school,38 hospital, and 86 husiness/industry foodservices. The statistical data analysis was completed using SPSS Win (ver 12.0) for descriptive analysis, t-test, Mann-Whitney U test. First, CFMCs had operational experience for an average of 8 years and 8 months, and served an average of 38,540 meals a day. Most of the respondent companies specialized in the school foodservice field and managed an average of 66 clients for the contract period of 2 years and 3 months. Second, the respondent companies had gotten a score of 77.78 points for the total average, 77.7 points in the large enterprise group and 78.1 points in the small and medium-sized enterprise group. Therefore, the minimum number of points for the accrediting license on Qualification is suggested to be over 70 out of a 100 point scale; this study would be serve as reference for the certification license on qualification. On the level of evaluation category, the scores were 14.15 to 20 points on $\ulcorner$finance$\urcorner$, 19.24 to 25 points on $\ulcorner$customer$\urcorner$, 19.33 to 25 points on $\ulcorner$process$\urcorner$, 14.31 to 20 points on $\ulcorner$human resource$\urcorner$, and 8.6 to 10 point on $\ulcorner$renewal and development$\urcorner$ . $\ulcorner$Renewal and development$\urcorner$ and $\ulcorner$customer focus$\urcorner$ received better grades than other evaluation categories. Third, $\ulcorner$Finance$\urcorner$ indicated similar distribution overall. Small and medium-sized companies had lower grades than large companies on 'market ability' of $\ulcorner$customer$\urcorner$ , but, clients of small and medium-sized companies had higher grade for 'client satisfaction' than large companies. Most of the companies supported 'infrastructure support for foodservice operation' of $\ulcorner$process$\urcorner$ by the main office of CFMCs, but, the branch chain offices of CFMCs were not applied efficiently. Large companies made more effort to improve the 'employee ability' of $\ulcorner$human focus$\urcorner$ than small and medium-sized CFMC. The 'research and development cost' of $\ulcorner$renewal and development$\urcorner$ was increased compared to the previous year. In conclusion, if CFMCs were to perform self-evaluation and a routine checkups by utilizing CFMC's IC measuring tool, improvements in CFMC operational capacities as well as foodservice quality can be noted. (Korean J Nutrition 38(10)'880$\sim$894,2005)

• The Korean Journal of Emergency Medical Services
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• v.12 no.1
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• pp.27-41
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• 2008

Purpose : With increasing number of school accidents, it is crucial to find out necessity of first aid training among school health educator. This study has been conducted to have an clear idea on the demands and necessity for first aid training and what kind of training is most required from school health educator. Method : In this study, questionnaires from 87 school health educator in elementary, middle and high school health educator in the city D were analyzed. The survey was carned out from May 26, 2008 to June 7, 2008 and from the collected data, frequency, independent two samples t-test, paired T-test, one way ANOVA and pearson's correlation were conducted with SPSS 14.0. Result: 1. 51.61 % of nurse-teachers experienced emergency situations and the relations between the necessity they felt from experiencing those situations and demands for first aid training were not statistically meaningful(t=1.87, p= .175). 2. Necessity and demands for the first-aid training were checked with three point scale and there were statistical significance between the two with $2.44{\pm}.47$ and $2.24{\pm}.47$ respectively(t=3.275, p= .000). 3. 86.20%(75 persons) of the respondents have had received first aid training and the training they received were CPR 82.75%(72 persons), primary survey 81.60%(7l persons), contact to 911 79.30%(69 persons) and wounds treatment(lacerated wounds, bum and chilblains) 75.86%( 66 persons) in order. 4. As for the questions that ask on confidence of first-aid treatment, 80% answered they are confident on some limited kinds of treatments, 16% said they are confident and 4% answered they lack confidence. As for the treatment that they can show the highest confidence, wounds treatment topped the list with 93.24%, nose bleeding and removing foreign substance, and stanching followed the list with 82.43% and 81.08% respectively. 5. 97.67% of respondents said they were willing to take training and 89.62% answered to take the training to deal with emergency situations that are taking place in their schools. As for the question that asks for the most wanted treatments, CPR topped the list with 32.18%(28 persons) and treatment for obstruction of airway and shock followed the list with 35.63%(31 persons) and 27.59%(24 persons). Conclusion : Currently, first aid treatment has been centered on CPR, primary survey, contact to 119 and wounds treatment. However, since most of school health educator are fairly confident with wounds treatment, stanching and other first aids, in future training it will be more desirable to focus on CPR and treatment for obstruction of airway and shock that were shown to be most wanted by school health educator.

• Journal of Microbiology and Biotechnology
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• v.29 no.3
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• pp.373-381
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• 2019

Site-directed mutagenesis was employed to generate five different triple point mutations in the double mutant (C295A/I86A) of Thermoanaerobacter ethanolicus alcohol dehydrogenase (TeSADH) by computer-aided modeling with the aim of widening the small alkyl-binding pocket. TeSADH engineering enables the enzyme to accept sterically hindered substrates that could not be accepted by the wild-type enzyme. The underline in the mutations highlights the additional point mutation on the double mutant TeSADH introduced in this work. The catalytic efficiency ($k_{cat}/K_M$) of the ${\underline{M151A}}$/C295A/I86A triple TeSADH mutant for acetophenone increased about 4.8-fold higher than that of the double mutant. A 2.4-fold increase in conversion of 3'-methylacetophenone to (R)-1-(3-methylphenyl)-ethanol with a yield of 87% was obtained by using ${\underline{V115A}}$/C295A/I86A mutant in asymmetric reduction. The ${\underline{A85G}}$/C295A/I86A mutant also produced (R)-1-(3-methylphenyl)-ethanol (1.7-fold) from 3'-methylacetophenone and (R)-1-(3-methoxyphenyl)-ethanol (1.2-fold) from 3'-methoxyacetophenone, with improved yield. In terms of thermal stability, the ${\underline{M151A}}$/C295A/I86A and ${\underline{V115A}}$/C295A/I86A mutants significantly increased ${\Delta}T_{1/2}$ by $+6.8^{\circ}C$ and $+2.4^{\circ}C$, respectively, with thermal deactivation constant ($k_d$) close to the wild-type enzyme. The ${\underline{M151A}}$/C295A/I86A mutant reacts optimally at $70^{\circ}C$ with almost 4 times more residual activity than the wild type. Considering broad substrate tolerance and thermal stability together, it would be promising to produce (R)-1-(3-methylphenyl)-ethanol from 3'-methylacetophenone by ${\underline{V115A}}$/C295A/I86A, and (R)-1-phenylethanol from acetophenone by ${\underline{M151A}}$/C295A/I86A mutant, in large-scale bioreduction processes.

• Journal of Dental Anesthesia and Pain Medicine
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• v.20 no.6
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• pp.367-375
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• 2020

Background: Intraosseous anesthesia (IO) allows the anesthetic solution to be injected directly into the cancellous bone. The anesthetic solution immediately reaches the periapical region, and thus the axonal area of the nerve, where it can temporarily disable the sodium pump. The effect is felt almost without any time delay, and only a small amount of anesthetic solution is required. Methods: This study aims to investigate the efficacy of IO using the AnestoⓇ device after infiltration anesthesia (IA) and/or inferior alveolar nerve block anesthesia (IANB) failed to work in symptomatic irreversible pulpitis (hot tooth). The 33 patients included in the study were treated additionally with 1.7 ml articaine hydrochloride with 1:100,000 epinephrine hydrochloride (UltracainⓇ D-S, Sanofi-Aventis, Frankfurt, Germany) IO. Results: The electrical pulp test showed that 95.76% of the volunteers reacted positively to the combination of IANB or IA with the IO. In women, the additive IO was effective at 97.22%. In men, the IO led to pain elimination in 94.00% of cases. The duration of the IO was less than a quarter of an hour (13.03 min). The IO worked longer in women than in men (13.61 min vs. 12.33 min). Overall, more than every third tooth that needed trepanation was located in the posterior area of the mandible (36.4%). Treatment of hot teeth in this area was associated with an increased pulse rate and increased residual pain. There was a moderate correlation (Spearman-Rho [IRI] = 0.280) between the Visual Analog Scale (VAS) score and bone density, and a significant correlation (IRI = 0.612) between subjective residual pain and bone width. The IO resulted in a moderate, transient increase in the pulse rate by approximately 20 bpm. This is similar to the temporary increase in heart rate after conventional anesthesia techniques in non-preloaded patients and can be considered clinically irrelevant. Conclusion: IO with the AnestoⓇ device as an extension and deepening of local pain elimination is recommended for the treatment of hot teeth.

• Land and Housing Review
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• v.13 no.1
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• pp.141-150
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• 2022

Responding to the increasing demand for research on seismic resistance of structures triggered by a large-scale earthquake in Korea, the Ministry of the Interior and Safety revised the typical application of the existing seismic design standards with the national seismic performance target enhanced. Therefore, in this paper, the dam body of the aged Test-Bed and the penstock with fluid were modeled by the three-dimensional finite element method by introducing several variables. The current seismic design standard law confirmed the safety of the dam structure and penstock against seismic waves. As a result of the 3D finite element analysis, the stress change due to the water impact of the penstock was minimal, and it was confirmed that the effect of the hydraulic pressure was more significant than the water impact in the earthquake situation. When the hydrostatic pressure is in the form of SPH, it was analyzed that the motion of the fluid and the location of stress caused by the earthquake can be effectively represented, and it will be easier to analyze the weak part. As a result of the analysis, which considers penstock's corrosion, the degree of stress dispersion gets smaller because the penstock is embedded in the body. The stress result is minimal, less than 1% of the yield stress of the steel. In addition, although there is a possibility of micro-tensile cracks occurring in the inlet of the dam, it has not been shown to have a significant effect on the stress increa.