• Proceedings of the SAREK Conference
• /
• 2006.06a
• /
• pp.993-998
• /
• 2006

High-rise apartments have a problem using natural ventilation because of the strong outdoor wind velocity. Conventional high-rise apartments have adopted mechanical ventilation systems to maintain the indoor air quality. However, it leads to the overuse of electricity and the sick house syndrome. Double-skin facade is the alternative for the high-rise building to use natural ventilation and this study is focused on the performance of the box-window, which is a kind of double-skin facades. Indoor wind velocity and HCHO concentrations are analyzed with three types of box-windows: the diagonal type, parallel type and perpendicular type. The airflow is simulated by computational fluid dynamics program. Box-windows reduce the maximum value of indoor wind velocity about 50% compared with the single window and the HCHO concentrations do not have the big difference. Box-windows could be the alternative to enhance the use of the natural ventilation and indoor air quality of the high-rise apartment.

• Journal of Korea Society of Industrial Information Systems
• /
• v.13 no.1
• /
• pp.46-56
• /
• 2008

Double Patching is a multicasting technique for a VoD system which has been proposed to provide a true VoD service by making clients share a long patching stream as well as a regular stream For subsequent short patching streams, the technique always makes the long patching stream have extra data that will be played back during a double period of a patching window. In this paper, we propose a technique, using the start time of the latest short patching stream, optimizes Double Patching by deleting the useless data included in the long patching stream when the patching window of the long patching stream closes. The mean requirement for the server's bandwidth to provide the true VoD service is used as a performance metric, and the effect of the request inter-arrival time, the size of the client's local buffer and the video length on the mean bandwidth requirement is evaluated. Performance evaluation result shows that the proposed technique optimizes Double Patching in all cases.

• International Commerce and Information Review
• /
• v.7 no.4
• /
• pp.157-177
• /
• 2005

In many countries, a Single Window system for simplifications is establishing in order to reduce works submitted double data and compliance costs. A Single Window is defined as a facility that allows parties involved in trade and transport to lodge standardized information and documents with a single entry point to fulfil all import, export, and transit-related regulatory requirements. A Single window can bring improved level of security, faster clearance and reduced compliance costs. UN/CEFACT released "Recommendation and Guidelines on establishing a Single Window to enhance the efficient exchange of information between trade and government". Also, WCO has made progress several projects to assist effective establishing a single window, i.e. CDM, UCR, ICT. Korea has being established a single window system, "e-trade platform" connected with trade, clearance, logistics, marketing and payment system. Some suggestions to establish a effective single window system in Korea are as follows. Firstly, it is necessary to clearly define roles and responsibilities of a lead agency in a single window system and form a organic relationship with PGA. Secondly, a single window system has to be progressed by stages, namely, customs clearance portal system should be established first, and later established e-trade platform. Lastly, the Korean government has to take part in CDM project to gain an advantage over other countries.

• Journal of the Korean housing association
• /
• v.24 no.6
• /
• pp.133-140
• /
• 2013

This study is to clarify the form of window and door of medieval times house which are no longer in existence, by comparative analysis between literature materials and architectural remains of united Silla and Goryo period. Particularly the window and door form change process of was analyzed, in connection with the change of term which are recorded in literature material. The form and the composition of window and door are the elements which determine the elevation design of architecture and concerned with interior environment. Therefore this study is significant in the sense that it could be used as base data for the study on the reconstruction and interior space of medieval times house. There were ho (戶) and moon (門) as door, and chang (窓) for lighting and ventilation as window. Among these, the window can be divided into fixed and openable. There were two kind of fixed window. One is called chang (窓), and it was covered by silk or paper for lighting. The other is called ham (檻), it was the form of vertical bar window and lighting and ventilation was available. And there were two kind of openable window. One is called ho (戶), which had wooden plate window leaves. And the other is called changho (窓戶), lighting was available in the condition of closing.

• The KIPS Transactions:PartC
• /
• v.15C no.4
• /
• pp.281-288
• /
• 2008

Recently, the advance of multimedia hardware has fostered the development of wireless multimedia sensor network which is able to ubiquitously obtain multimedia content such as image or audio from the environment. The multimedia data which has several characteristics such as large size and correlation between the data requires reliability in transmission. However, the existing solution which take the focus on the efficiency of network mainly, is not appropriate to transmit the multimedia data. In the paper, we proposes a reliable asynchronous image transfer protocol, RAIT. RAIT applies double sliding window method in node-to-node image tansfer to prevent the packet loss caused by network congestion. The double sliding window consists of one sliding window for the receiving queue, which is used for prevention of packet loss caused by communication failure between nodes and the other sliding window for the sending queue which prevents the packet loss caused by network congestion. the routing node prevents the packet loss and guarantees the fairness between the nodes by scheduling the packets based on the image non-preemptively. The RAIT implements the double sliding window method by cross layer design between RAIT layer, routing layer, and queue layer. The experiment shows that RAIT guarantees the reliability of image transmission compared with the existing protocol.

• Journal of the Korean Institute of Telematics and Electronics S
• /
• v.36S no.9
• /
• pp.9-17
• /
• 1999

In this paper, we present a mathematical modeling and perform a performance analysis of double-dwell serial search algorithm, which has a search window concept, for pilot channel in DS-CDMA(Direct Sequence Code Division Multiple Access). We derive a code detection function, a false alarm function, a code miss function, and a mean code acquisition time for the performance analysis. We calculate the mean code acquisition time of the mathematical model in IS-95 forward link and compare it with that of the conventional search methods. The performance of the code acquisition system is also evaluated to investigate the effect of dwell times and search window size. The JTC channel model, which is a PCS channel model in North America, is used for the analysis. The numerical result shows that the mean code acquisition time of the double-dwell serial search algorithm with a search window is reduced by about 17%~25% than those of the conventional ones.

• Journal of the Korean Solar Energy Society
• /
• v.40 no.1
• /
• pp.49-60
• /
• 2020

This study reviewed selected specific windows and reviewed the window performance certification criteria including KS F 2278 and KS L 9107 and analyzed the change in performance based on the change of area. This study also compared the heating and cooling loads of an apartment house applied with window performance reviewed in consideration of insulation and SHGC performance and actual size based on KS F 2278. The analyzed window was a double window composed of aluminum and PVC and the building was the apartment house model of 141 ㎡. The analysis results were as follows. First, as the window glass's thermal performance is superior to frame, the performance degraded in reduced area. In case of selected window, the 1 m × 1m window's thermal performance and SHGC decreased by 35% and 37% respectively compared to 2 m × 2 m window. Secondly, in the comparison of performance for increasing area with 2 m × 2 m and 3 m × 3 m windows, the 3 m × 3 m window's thermal performance and SHCG increased about 14%. Third, in the comparison of heating and cooling loads of the analyzed model considering the apartment house model applied with window performance derived from KS F 2278 and actual figures, the model's total heating and cooling loads increased by 33% with cooling decreasing by 36% and heating increasing by 77%. Above analysis results show that evaluation of window performance based on criteria such as KS F 2278 and KS L 9107 may lead to distortion of performances different from actual products. Thus, it is necessary to suggest new evaluation criteria.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.48 no.7
• /
• pp.9-16
• /
• 2011

In this paper, various kinds of high throughput turbo decoding schemes are introduced, and a new turbo decoding scheme using the advantages of each scheme is proposed. The proposed scheme uses the decoding structure of double flow scheme, sliding window scheme and shuffled turbo decoding scheme. Simulation results show that the proposed scheme offers a BER performance equivalent to those of existing turbo decoding schemes with less clock cycles. We also show that the required memory can be reduced by choosing proper size of sliding window. Consequently, we can design a high throughput turbo decoder requiring low power and low area.

• 한국신재생에너지학회:학술대회논문집
• /
• 2007.06a
• /
• pp.276-279
• /
• 2007

This study aims to present the application of pv system for apartment buildings. Regarding to the domestic housing politics to improve residing environment and effective use of country land, apartment buildings have been constructed since early of 1790's. Now apartment is taking over 50% out of entire housing in Korea. PV System of apartment buildings has been developed periodically and recently gable roof or canopy is popular which pv installation is more favorable. For balcony part with double skin facade sassy window, it has a preferable condition to install on the wall depending on the window direction. In case of superhigh floor apartment buildings where facade is mostly double skin facade of curtain wall system, pv module can replace the traditional curtain wall and will reduce architectural materials and obtain various out look design thereof. So, the purpose of this research is a basic study for clean energy source and present to applicability of pv systems for apartment buildings in preliminary design step.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2011.10a
• /
• pp.457-462
• /
• 2011

The sidewall of the HEMU-400x consists of two parts. One is the multi-layered structure including aluminium extruded panel and the other is the double glazed window. When the train runs in a tunnel, the equivalent sound insulation performance of the side wall significantly influences the internal noise levels. In aspect of the sound insulation strategy, it is important to make two parts have similar performance. In this study, the intensity sound transmission loss (ITL) is measured on the specimens of the two parts. Mass law deviation (MLD) is considered in order to compare the sound insulation performance of the two parts in respect of the weight. Contribution of each part to the sound insulation is analyzed and the sound insulation strategy is investigated to reduce the interior noise.