• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.28 no.5A
• /
• pp.276-283
• /
• 2003

Most of CDMA system algorithm must be verified by simulating the cellular system consisted of many other tier cells. But it takes long time to simulate such a huge CDMA cellular system. In this paper, we propose an effective time saving simulation scheme based on wraparound technique. And we study that how our remaining cell interference compensation method works on calculating of the total interference, SIR, outage probability, and cell capacity. We made a conclusion that by using proposed scheme, we can get the same result of maximum configuration cells with only one tier real cells and that we can minimize the simulation time.

• Journal of Arbitration Studies
• /
• v.17 no.3
• /
• pp.145-167
• /
• 2007

Digital goods are defined as intangible and non-physical goods, composed of a combination of digital signals, electronically represented as 0 and 1. They are also called as digital products, electronic transmissions, information goods, digital contents, computer information, etc. Digital goods are now traded both domestically and internationally as well as on-line and off-line. Korean government revised the Basic Law on Foreign Trade to include digital goods and services as the scope of foreign trade in 2001. Trade volume of digital goods are increasing in Korea. The supply chains of digital goods from producing the components to selling globally to consumers are different from conventional physical goods. Mostly, digital goods are traded on the license basis rather than ownership contract. End User License Agreements(EULAs), such as shrink-wrap, click- wrap, or browser-wrap licenses are very popular in online transactions. Unlike conventional physical goods. the breach of license contract is closely linked with the infringement of intellectual property rights. Digitalized intellectual property is easy to copy and transmit in the cyber space. In cases of legal disputes from the breach of license contract, commercial arbitration or on-line alternative dispute resolutions(ADRs) are regarded as better approach to solve them rather than court sues. For promoting more secure and reliable international trade of digital goods. arbitration clauses should be included in most of license contracts.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.24 no.10 s.181
• /
• pp.2428-2437
• /
• 2000

In general, it is known that the portion of leakage loss is more than 20 % of total loss in scroll compressor. So far many studies have been done to improve the leakage problem and volumetric efficiency. In order to do this it is necessary that the leakage is exactly evaluated for conventional scroll model. Almost all studies that have been done were assumed that the clearance remains constant while operating. But in actual operating conditions, scroll wrap is deformed due to elevated refrigerant gas temperature. And this makes the leakage clearance change, so the leakage mass flow and the volumetric efficiency are also changed. In this study we assumed the steady state operating condition and obtain the average temperature and convection heat transfer coefficient in terms of involute angle. With these results, using finite element method we analyzed the heat transfer of scroll wrap, then did thermal deformation analysis. Then we obtain the leakage clearance and do the leakage and volumetric efficiency analysis. Compared with undeformed feature, we examine the effect of the thermal deformation on the leakage. The results say that the leakage mass flow for the case of considering thermal deformation is less than that for the unconsidered one, and this means that the leakage clearance is reduced due to thermal deformation.

• Advances in concrete construction
• /
• v.10 no.2
• /
• pp.93-104
• /
• 2020

Basalt fiber is an eco-friendly fiber and comparatively newer to the world of fiber-reinforced polymer (FRP) composites. A limited number of studies have been reported in the literature on the strengthening of reinforced concrete (RC) beams with basalt fiber reinforced polymer (BFRP). The present experimental work explores the feasibility of using the BFRP strips for shear strengthening of the RC beams. The strengthening schemes include full wrap and U-wrap. A simple mechanical anchorage scheme has been introduced to prevent the debonding of U-wrap as well as to utilize the full capacity of the BFRP composite. The effect of varying shear span-to-effective depth (a/d) ratio on the behavior of shear deficient RC beams strengthened with BFRP strips under different schemes is examined. The RC beams were tested under a four-point loading system. The study finds that the beams strengthened with and without BFRP strips fails in shear for a/d ratio 2.5 and the enhancement of the shear capacity of strengthened beams ranges from 5% to 20%. However, the strengthened beams fail in flexure, and the control beam fails in shear for a higher a/d ratio, i.e., 3.5. The experimental results of the present study have been compared with the analytical study and found that the latter gives conservative results.

• Proceedings of the Korea Water Resources Association Conference
• /
• 2015.05a
• /
• pp.282-282
• /
• 2015

도시화로 인한 지구 온난화는 현재 전 세계적으로 기후 및 자연환경에 적지 않은 영향을 미치고 있으며, 인구증가에 따른 물 부족 현상은 새로운 저수지 건설로 지속 가능한 수자원 개발이 불가능한 현 상황에서 더욱더 악화되고 있는 실정이다. 이에 따라 제한된 물 사용에 대한 효율적인 배분이 필요한 상황이며 이를 위하여 사용 가능한 물에 대한 권리, 즉 수리권(water rights)에 대한 자료 및 조사가 필요한 상황이다. 현재 국내 수리권에 대한 자료는 국가 수자원 관리 종합 정보 시스템(Water Management Information System, WAMIS)에서 특정년도에 생활, 공업 및 농업용수에 대하여 정보가 권역, 시도 및 하천등급별로 구성되어 있는 상황이다. 이에 따라 본 연구에서는 텍사스 수자원 관리 모델인 Water Availability Model(WAM) 시스템의 구성 요소 모델인 Water Rights Analysis Package (WRAP) 모델에 적용하기 위하여 권역별로 구성되어 있는 수리권 정보를 물 사용자의 지정학적 위치 및 점용년도에 따라 재구성하였다. 한강유역의 수리권 정보를 중점으로 수행되었으며 재구성 수리권 정보는 자연 순위 (natural order) 및 우선 순위 (priority order) 수리권의 두가지 형태의 입력값으로 WRAP 모델에 활용되었다.

• Archives of Plastic Surgery
• /
• v.49 no.3
• /
• pp.365-368
• /
• 2022

Spinal extradural arachnoid cyst (SEAC) is a rare disease and has surgical challenges because of the critical surrounding anatomy. We describe the rare case of a 58-year-old woman who underwent extradural cyst total excision with dural repair and presented with refractory cerebrospinal fluid (CSF) leakage even though two consecutive surgeries including dural defect re-repair and lumbar-peritoneal shunt were performed. The authors covered the sacral defect using bilateral gluteus maximus muscle flap in tongue in groove and wrap around pattern for protection of visible sacral nerve roots and blockage of CSF leakage point. With the flap coverage, the disappearance of cyst and fluid collection was confirmed in the postoperative radiological finding, and the clinical symptoms were significantly improved. By protecting the sacral nerve roots and covering the base of sacral defect, we can minimize the risk of complication and resolve the refractory fluid collection. Our results suggest that the gluteus muscle flap can be a safe and effective option for sacral defect and CSF leakage in extradural cyst or other conditions.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.44 no.7 s.361
• /
• pp.71-80
• /
• 2007

This paper describes an efficient hardware design of WiBro security processor (WBSec) supporting for the security sub-layer of WiBro wireless internet system. The WBSec processor, which is based on AES (Advanced Encryption Standard) block cipher algorithm, performs data oncryption/decryption, authentication/integrity, and key encryption/decryption for packet data protection of wireless network. It carries out the modes of ECB, CTR, CBC, CCM and key wrap/unwrap with two AES cores working in parallel. In order to achieve an area-efficient implementation, two design techniques are considered; First, round transformation block within AES core is designed using a shared structure for encryption/decryption. Secondly, SubByte/InvSubByte blocks that require the largest hardware in AES core are implemented using field transformation technique. It results that the gate count of WBSec is reduced by about 25% compared with conventional LUT (Look-Up Table)-based design. The WBSec processor designed in Verilog-HDL has about 22,350 gates, and the estimated throughput is about 16-Mbps at key wrap mode and maximum 213-Mbps at CCM mode, thus it can be used for hardware design of WiBro security system.

• Korean Journal of Food Science and Technology
• /
• v.32 no.6
• /
• pp.1244-1250
• /
• 2000

A method for simultaneous quantitative determination of plasticizers such as diethyl phthalate(DEP), di-n-propyl phthalate(DprP), di-n-butyl phthalate(DBP), di-n-pentyl phthalate(DPP), butylbenzyl phthalate(BBP), di-(2-ethylhexyl) phthalate(DEHP), dicyclohexyl phthalate(DCHP) and di-(2-ethylhexyl) adipate(DEHA), which are suspected as endocrine disruptors, in food was studied. A analysis method was optimized for the quantification of plasticizers in Jjambbong, which is a kind of fatty noodle, by using GC/FID. The detection limits of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 3.5, 5.3, 2.2, 2.2, 7.2, 1.7, 1.9 and 3.0 mg/kg, respectively. Much higher recovery was obtained by extraction with acetone/n-hexane(1:1) rather than hexane solvent system. The recovery of DEP, DprP, DBP, DPP, BBP, DEHP, DCHP and DEHA were 72.7, 85.9, 91.4, 97.1, 100.8, 103.2, 104.3 and 95.8% after 4 time extractions, respectively. The migration of plasticizers from PVC wraps into PVC wrap covered Jjambbong was conducted after shaking(120 rpm) for 30min at room temperature with chosen solvent system. It was found that the migration level of DEHA were 577, 706, 770 mg/kg into Jjambbong, respectively, while the other plasticizers were not observed.

• The monthly packaging world
• /
• s.150
• /
• pp.92-96
• /
• 2005

• 소프트웨어공모대전
• /
• s.8
• /
• pp.181-188
• /
• 2003