• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.410-415
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• 2004

Heavy-weight head slides may cause excessive inertia impact ＆ moment on the machine tool structure when they move or stop abruptly during operation. Consequently these inertia impact and unbalanced moment bring transient vibrations and rough sliding motions on the machine structure. Machine tool engineers have tried many kind of feed-slide designs in order to solve this problem; for example, the design optimization of the moving structure for minimum weight and maximum stiffness, box-in-box type slide design, and so on. In this article, force and moment equilibrium equations regarding to the inertia force ＆ moment were derived for each one of a mold M/C's head slides. Furthermore, five different design configurations of head slide assembly were reviewed for its design improvement regarding to force ＆ moment calculations and finite element structural analysis results.

• Journal of Power System Engineering
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• v.19 no.2
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• pp.57-63
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• 2015

In this paper, we developed a continuous sterilizer in order to improve the productivity of the retort product. To this end, we design the sterilizer with a product inlet, outlet, and chain for continuously conveying the retort. The temperature analysis is performed to optimize the design parameters of the internal sterilizer. The experimental apparatus is developed to verify the productivity of the sterilizer based on the temperature analysis. The test is performed to optimize the evaluation parameters using Box-Behnken design method of a response surface methodology. From the test, the productivity of the continuous sterilizer is improved over 1,000 kg/h.

• International Journal of Railway
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• v.8 no.1
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• pp.5-9
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• 2015

Reliability based limit state design method is replacing traditional deterministic designs such as allowable stress design and/or ultimate strength design methods in world trends. European design code(Eurocode) has adopted limit state design, and Korea road bridge design standard has also recently been transferred to limit state design method. In this trend, Korea railroad design standard is also preparing for adopting the same design concept. While safety factors are determined empirically in traditional design, load combinations as well as load factors are determined by solving limit state equations. General partial safety factors are evaluated by using AFORM(Advanced First Order Reliability Method) in the reliability based limit state design method. In this study sensitivity analysis is carried out for a dead load factor and a live load factor. Relative precisions of the dead load and the live load factors are discussed prior to the AFORM analysis. Furthermore the sectional forces of design and the material quantities required by two different design methods are compared for a PSC box girder railway bridge.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.29 no.1
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• pp.27-33
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• 2023

An optimized design of the transportation insulated box must be considered to control the thermal damage in order to maintain the fresh condition for temperature-sensitive medicine and frozen food safety. The inside temperature of the insulated box is a natural convection enclosure state, thermal stratification naturally occurs as time passes in case of with outside heat load. The latent heat material (LHM) placement inside the box maintains the target temperature of the product for temperature fluctuations during transport, and LHM application is a common and efficient method. In this work, inside temperature stratification in an insulated box depending on the LHM pack position is numerically simulated and experimented. The insulated box is made up of vacuum insulation panel (VIP), and LHM modules are placed over six faces inside the box, with the same weight. The temperature curves for 72 hrs as experiment results clearly show the temperature stratification in the upper, middle, and lower at the LHM melting time region. However, the temperature stratification state is uniformly changed in accordance with the condition of the upper and lower placement weight of the LHM pack. And also, the temperature uniformity by changed placement weight of LHM has an effect on maintaining time for target air temperature inside the box. These results provide information on the optimized design of the insulated box with LHM.

• Design Convergence Study
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• v.14 no.4
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• pp.1-16
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• 2015

This study aims to understand distribution of the sentimental words on each genre and find relationship between box office performance and sentimental words in movie review using 673 movies that have more than 1,000 reviews. For the analysis, crawling movie reviews and made data was composed movie genre, movie name, sales, attendance, screen, normal attendance, 7 sentimental words. For analysis results, we used correlation analysis and Parallel coordinates. As a results, First, the highest box office value of the genre is comedy and the lowest box office value of the genre is horror through analyze box office on each genre. Secondly, Movie genre of fantasy feel a lot of boring emotion and Movie genre of SF feel a lot of anger emotion even if 'Happy' and 'Surprise' have highest sentiment value on every genre. Third, We found 'Anger' increase sentimental value when 'Disgust' increase sentimental value and 'Surprise' decrease sentimental value when 'Happy' increase sentimental value through analyze correlation relationship between sentimental words using total data. Fourth, We found 'Happy' have linear relationship between box office and 'Fear' have non-linear relationship between box office through analyze sentimental words according to box office performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.133-139
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• 2016

In order to obtain a reasonable value for the thermal load to use in designs, a bridge specimen of a full-size steel box girder (bridge) was manufactured. The temperature data were measured at 21 points in the bridge specimen and 19 points in the steel box bridge. The steel box bridge specimen was installed in a similar direction to a nearby real one. The maximum effective temperatures in the bridge specimen and bridge were calculated for air temperatures in the range of $24^{\circ}C{\sim}38^{\circ}C$. The maximum effective temperature of the bridge specimen and bridge showed correlations of approximately 93.2% and 87.4%, respectively, compared with the Euro code. The maximum effective temperature calculated in this study was very close to the Euro code and the maximum temperature of the Highway Bridge Design Criteria. When the effective temperature obtained in the study is combined with the highest temperature calculated from the Contour map for each region, the design criteria for the thermal load in domestic bridge design, taking into consideration the characteristics of each region, can be established.

• Journal of Korean Society of Steel Construction
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• v.17 no.2 s.75
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• pp.115-130
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• 2005

This paper presents the effects of indirect costs on Life-Cycle-Cost(LCC) effective optimum design of steel-box girder bridges. The LCC formulations considered in the LCC optimization of the bridges consist of initial cost and expected rehabilitation costs including repair/replacement costs, loss of contents or fatality and injury losses, and indirect costs such as road user costs and indirect socio-economic losses. To demonstrate the LCC-effectiveness for optimum design of the bridges, an actual steel box girder bridge having two continuous spans(2@50m=100m) is considered as a numerical example. And also, in this paper, various sensitivity analyses are performed to investigate the effects of indirect costs caused by traffic conditions such as number of detour route, number of lane on detour route, length of detour route, and traffic volumes on the LCC-effective optimum design. From the numerical investigations, it may be concluded that indirect costs caused by traffic network may sensitively influence on the LCC-effective optimum design of steel-box girder bridges. Therefore, it may be stated that the traffic conditions should be considered as one of the important items in the LCC-effective optimum design of the bridges.

• Journal of Engineering Education Research
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• v.13 no.5
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• pp.36-40
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• 2010

The vehicle oriented block box system based on the u-healthcare and the human-free guard functions is developed in this paper. We also suggested the design philosophies, ideas, and analyzed the performance of the suggested system. The developed vehicle oriented black box system has some characteristics such as; 1) detects the dangerous situation by ultrasonic sensor in advance, and stores the situation information of the neighborhood of the vehicle to the imbedded SD memory card if the dangerous situation may be occurred in the parked vehicle; 2) detects the present location and speed information of the vehicle by GPS receiver and 3-axes acceleration sensor, and stores the information to the SD memory card periodically if the vehicle is running; 3) measures the dioxide carbon in the vehicle inside using $CO_2$ sensor, and forces the ventilation motor of the vehicle to operate and maintains the driver's health if the measured level is more than standard health requirements; 4) provides the stored vehicle's operating information to the driver by GUI (Graphical User Interface) based touch LCD monitor.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.9 no.2
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• pp.11-22
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• 1989

The finite element utilizing isoparametric plate element is applied for the elastic analysis of straight box girder bridges. A continuous box girder is analyzed as an example to verify the validity and accuracy of this method. It is indicated that the deflections and longitudinal stresses obtained by this method agree well with those from the orther methods. This theory may, therefore, be directly used as an efficient tool to analyze and design box girder bridges subjected to arbitrary loading and boundary conditions.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 1999.04a
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• pp.313-321
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• 1999

To design steel box girder bridge, designers have taken the classical load distribution coefficient methods. Due to the rapidly developing computer technique, steel box girder bridge is simply modeled as grillage method for analyzing the girder, or as fully finite element method for more accurate and detailed analysis. Recently, cruciform space frame method is developed for modeling and analyzing it more simply and easily compared with finite element method. So, this study for the examination of upper methods' characteristics loaded unit moment load and analyzed the distortional deflection with shell element method and cruciform space frame method, and for three span three girder steel box bridge, loading DB-24 loads, analyzed it by upper methods and compared the results.