• Journal of the Korea Concrete Institute
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• v.16 no.2 s.80
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• pp.221-228
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• 2004

In recent years building floors become larger and more spacious due to the development of new design methods and high strength and light weight materials. However, such long span floor systems may provide smaller amount of damping and have a longer period so that they may be more vulnerable to the floor vertical vibration. In Korea when floors are to be checked against the floor vertical vibration, the provisions developed in foreign countries have been used. However these guidelines have been developed based on human perception, which may vary from country to country. Also, Korea have particular floor systems, such as flat plate floor system of apartment building. This study attempts to evaluate the vibration performance of the floors in typical apartment buildings. Two different floors with the area of $28 m^2$ and $32 m^2$ were investigated. The criteria provided by ATC-1(1999), AISC-11(1997), AIJ(1991) and the local criteria developed in the previous study(Han, 2003) was used to check the acceptability of the floor vertical vibration.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.5 no.1
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• pp.13-20
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• 1985

Two Cable-Stayed bridge on south coast in Korea has not constructed until a quarter of a century past since the beginning of it's own era. Our country is about to be interested in such a type of bridge. It has succeeded in constructing the 500 m spanned bridge against wind and earthquake in other several countries. Many contries are striving for designning a long spanned bridge to 1000m. For the realization of such a long spanned bridge in Korea clues to the problems, "How to design it", should be solved one by one. One of difficulties is in analysing the mechanical system because of multi-orter indeterminacy. In this study one of the numerical methods is proposed in order to eliminate the troublesome.

• Journal of Korean Society of Steel Construction
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• v.9 no.3 s.32
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• pp.341-350
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• 1997

The objective of this study is to investigate the structural behavior of the composite slabs with the new metal deckplate. The new deckplate can be used as structural member with topping concrete. So several experiments of this structural test and the fire resistance test were done. From this experiments. slabs with new metal deckpklate were verified as composite slabs. In this paper, this verifications were compared with the international design methods. For experiment. 49 specimens were made. the main parameters are deckplate thickness (1.2mm. 1.6mm) depth of topping concrete(85mm. 90mm). support condition(simple, 2-span), shear reinforcment(studs), span(2.7m, 3.0m, 3.3m. 3.6m. 3.9m) and shear span(L/3, L/4, L/7). We analyzed the structural behavior of composite slab throughout the moment-curvature relationship which is obtained with the program using the computer language. Turbo C. From this development for slab system, the reinforced concrete or steel structure building may be easy, economical for construction, And informations about the structural behavior of composite slabs will be utilized to established korea standard.

• Journal of the Institute of Electronics Engineers of Korea CI
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• v.48 no.1
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• pp.116-126
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• 2011

In this paper, we present a multi-media processor which can decode multiple-format video standards. The designed processor is evaluated with optimized MPEG-2, MPEG-4, and AVS (Audio video standard). There are two approaches for developing of real-time video decoders. First, hardware-based system is much superior to a processor-based one in execution time. However, it takes long time to implement and modify hardware systems. On the contrary, the software-based video codecs can be easily implemented and flexible, however, their performance is not so good for real-time applications. In this paper, in order to exploit benefits related to two approaches, we designed a processor called ASIP(Application specific instruction-set processor) for video decoding. In our work, we extracted eight common modules from various video decoders, and added several multimedia instructions to the processor. The developed processor for video decoders is evaluated with the Synopsys platform simulator and a FPGA board. In our experiment, we can achieve about 37% time saving in total decoding time.

• The Journal of the Korea institute of electronic communication sciences
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• v.1 no.1
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• pp.56-62
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• 2006

Currently, Most of the Backhual and Submarine's networks are being installed using DWDM and EDFA to deal with dramatically increasing internet traffic. In a conventional type optical system, the so-called 3R repeater, fiber non- linearity was not significant factor but it is one of the most important consideration when designing new DWDM network based on the EDFAs. To minimize the signal pulse distortion in long-haul optical network, Zero-dispersion fiber is indispensable but causes the fiber non-linearity. Therefore this conflicting problems should be managed to transmit a high-speed capacity traffic. In this paper, key technologies in DWDM submarine optic network were found out for a high capacity traffic and introduced the dispersion management way for solving the conflicting problems between Zero-dispersion and non-linearity. Lastly designed a dispersion map in section between Korea and Hong-kong.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.875-888
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• 2013

The researches have recently progressed toward the use of the superelastic shape memory alloys (SMAs) to develop new smart control systems that reduce permanent deformation occurring due to severe earthquake events and that automatically recover original configuration. The superelastic SMA materials are unique metallic alloys that can return to undeformed shape without additional heat treatments only after the removal of applied loads. Once the superelastic SMA materials are thus installed at the place where large deformations are likely to intensively occur, the structural system can make the best use of recentering capabilities. Therefore, this study is intended to propose new buckling-restrained braced frames (BRBFs) with superelastic SMA bracing systems. In order to verify the performance of such bracing systems, 6-story braced frame buildings were designed in accordance with the current design specifications and then nonlinear dynamic analyses were performed at 2D frame model by using seismic hazard ground motions. Based on the analysis results, BRBFs with innovative SMA bracing systems are compared to those with conventional steel bracing systems in terms of peak and residual inter-story drifts. Finally, the analysis results show that new SMA bracing systems are very effective to reduce the residual inter-story drifts.

• Journal of Korean Society of Forest Science
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• v.83 no.3
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• pp.299-310
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• 1994

This study was carried out to examine the optimal road spacing and road density to minimize the total harvesting cost(road construction cost plus yarding cost) for mechanized yarding system to roadside by one - and two-stage two-way in Forestry build-up region. Chunchon-kun, Kangwon-do. The estimated road construction costs were ranged from ten million won to sixty million won per km. The results have indicated that cable crane was appropriate for yarding machine by one-stage, two-way, and estimated optimal road spacing was 1,698m~4,192m, averaged 3,087m, and road density was 3.44m/ha~8.44m/ha, and averaged 5. 12m/ha. In hilly terrain, combination of medium yarder and Logging bogie was suited to yarding machine by two-stage, two-way, and calculated optimal road spacing was 1,483m~3,481m, averaged 2,589m, and road density was 4.05m/ha~9.46m/ha, averaged 5.90m/ha. In steep terrain, combination of medium yarder and jinsung winch was suited, and estimated optimal road spacing was 1,693m~3,982m, averaged 2,960m, and road density was 3.68m/ha~8.64m/ha, averaged 5.38m/ha.

• Survey Research
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• v.10 no.1
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• pp.91-112
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• 2009

The aim of this study is to suggest a new website measurement scale revised in accordance with the present tendency, and to test the practical use of it. The empirically current studies suggest the information, connectivity, practical function, lay - out, design, interlace, system, service as a website measurement scale. However. this study suggest a new website measurement scale including communication between internet users, platform for editing information. The test of a practical use about measurement scale progressed by a survey on computer access. A sample of 300 internet users answered the question based on a new website measurement scale. The result of this study shows that primary factors of the website measurement scale are information, user interface, website service, and communication. The influence of these factors on user's website preference changed as compared with the past. The result also shows that there is close correlation between information factor and communication factor. And the communication factor suggested on this study has effected in user's website satisfaction. Results imply that the idea of web2.0 is practically an important strategy for improving website satisfaction. And, because influence of primary factors on the website satisfaction has changed continually, strategic planning will have to be kept up.

• Korean Journal of Medicinal Crop Science
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• v.5 no.1
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• pp.67-71
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• 1997

Bupleurum falcatum is one of the oldest medicinal crop spontaneously generated as well as cultivated by man and successfully grown during the summer season in Korea. This study was conducted to examine the effect of planting density in the row spacing and hill spacing system using machine seeder on major agronomic traits, yield and labor saving. In 1993 and 1994, a spilt plot design was used with row spacing as the main plot and hill spacing as subplot. Labor saving efficency of the machine seeder reduced 96% than the hand seeding in sowing time required. Number of seeding stand increased, but stem height and number of nodes did not affect with different density in each row and hill spacing. There were reduced with narrow hill spacing on stem diameter, number of branches, shoot weight and root traits. There was no significant interaction between row and hill spacing for any major traits studied except shoot weight. Yield was more increase at 20cm than at 30cm row spacing. For these studies the optiomum density appears to be between drilling or 5cm hill spacing with 20cm row spacing. A highly significant positive correlation was appeared between number of seedling stand and root yield.

• Journal of Broadcast Engineering
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• v.5 no.1
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• pp.94-101
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• 2000

User adaptive reception of broadcast programs includes the functionality such as the user adaptive filtering and browsing functionality. The user adaptive filtering means that the user can limit the list of programs to include only his/her favorite programs among hundreds of available programs. The user adaptive browsing means that the user can view a short summary of his/her selection in the way that he/she prefers. When the receiving system include the random access storage device, the automatic recording functionality of users favorite programs can be included. The user adaptive reception requires support from various meta-data such as user preference data and content description data. TV Anytime forum is a standardization effort to enable user adaptive TV reception, which means that the user can watch what s/he wants when s/he want in the way s/he wants. MPEG-7 includes not only the content description for broadcast applications but also other content descriptions such as structure information. This paper addresses the relationship between MPEG-7 and TV Anytime and investigates how MPEG-7 should be designed and be used to satisfy the requirements of the user adaptive reception of broadcast program.