• Structural Monitoring and Maintenance
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• 제1권2호
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• pp.183-195
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• 2014

Scour is one of the leading causes of overwater bridge failures worldwide. While monitoring systems have already been implemented or are still being developed, they suffer from limitations such as high costs, inaccuracies, and low reliability, among others. Also, most sensors only measure scour depth at one location and near the pier. Thus, the objective is to design a simple, low cost, scour hole topography monitoring system that could better characterize the entire depth, shape, and size of bridge scour holes. The design is based on burying a robust, waterproofed, piezoelectric sensor strip in the streambed. When scour erodes sediments to expose the sensor, flowing water excites it to cause the generation of time-varying voltage signals. An algorithm then takes the time-domain data and maps it to the frequency-domain for identifying the sensor's resonant frequency, which is used for calculating the exposed sensor length or scour depth. Here, three different sets of tests were conducted to validate this new technique. First, a single sensor was tested in ambient air, and its exposed length was varied. Upon verifying the sensing concept, a waterproofed prototype was buried in soil and tested in a tank filled with water. Sensor performance was characterized as soil was manually eroded away, which simulated various scour depths. The results confirmed that sensor resonant frequencies decreased with increasing scour depths. Finally, a network of 11 sensors was configured to form a distributed monitoring system in the lab. Their exposed lengths were adjusted to simulate scour hole formation and evolution. Results showed promise that the proposed sensing system could be scaled up and used for bridge scour topography monitoring.

• 인터넷정보학회논문지
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• 제5권3호
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• pp.11-23
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• 2004

컴퓨터 및 네트워크의 발달로 무한한 정보들을 쉽고 빠르게 사용할 수 있게 되었지만 이에 따른 부작용도 증가되었다. 이러한 부작용에는 해킹이나 크래킹 개인정보 유출 등이 있으며 최근에는 컴퓨터 바이러스가 심각한 문제로 제기되고 있다. 컴퓨터 바이러스에 대한 해결책은 안티 바이러스이다. 안티 바이러스는 클라이언트 측에 설치되어 서버에서 바이러스의 시그니쳐를 내려받아 업그레이드 하는 형태로 구현되고 있으나 최근에는 서버와 연동하는 제품들도 생겨나게 되었다. 그러나 이러한 안티 바이러스 시스템들은 사용자의 무관심으로 적절히 시그니쳐가 갱신되지 않으면 안티 바이러스가 정상적으로 자동하지 않으며 인격관리가 되지 않는다는 단점이 있다. 따라서, 본 논문에서는 이러한 문제를 해결하기 위하여 인터넷 서버에 설치되어 원격으로 관리할 수 있는 웹기반 안티 바이러스 스캐너(WAVScanner)를 설계 및 구현하였다. 이를 통해 새로운 바이러스에 대한 효과적인 안티바이러스 대책 수립과 백신 개발을 가속화할 수 있을 것이다.

• Archives of Plastic Surgery
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• 제45권4호
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• pp.325-332
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• 2018

Background Zygomaticomaxillary complex (ZMC) fractures mostly occur in the form of tripod fractures. The surgical field is accessed using a combination of three classic approaches. However, the subciliary incision may have unfavorable aesthetic results. Herein, the authors report the advantages of the extended transconjunctival approach (ETA) combined with T-bar screw reduction in minimizing scarring and complications for the treatment of ZMC fractures. Methods A total of 26 patients underwent ZMC reduction through the ETA and intraoral approach. A skin incision measuring roughly 5 to 8 mm in length was placed following the lateral canthal skin crease. After releasing the inferior crus of the lateral canthal tendon for canthotomy, the medial periosteum of the lateral orbital rim was preserved for canthal reattachment. A limited subperiosteal dissection and partial relaxing incision of the orbicularis oculi were performed to expose the fracture line of the inferior orbital rim and zygomaticofrontal suture. Reduction was performed using a T-bar screw through the transconjunctival incision and an elevator through the intraoral incision. Results The aesthetic and functional results were excellent. Successful reduction was achieved and the skin incision was less than 8 mm in 20 cases (76.9%). Only six patients had an additional skin incision (less than 5 mm) to achieve reduction. No cases of ectropion, entropion, or excessive scarring were noted. Conclusions The ETA using a T-bar screw is a useful method for maximizing aesthetic results in ZMC fractures, with the advantages of minimal scarring, faster recovery, and maintenance of pretarsal fullness.

• Radiation Oncology Journal
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• 제2권1호
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• pp.149-153
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• 1984

Postoperative radiotherapy of breast cancer makes it possible to reduce loco-regional recurrence of breast cancer. The treatment technique, which can reduce the low-dose region at the junction and lung, is required. To produce proper dose distribution of internal mammary chain and chest wall, authors tried to find the method to expose $^{60}Co\;\gamma-ray$ on internal mammary region and 7MeV electron on chest wall. Exposure time of $^{60}Co\;\gamma$ and monitor unit of 9MeV were selected so that dose of $^{60}Co$ at 4cm depth was the same as that of 7Mev electron at $80\%$ dose depth. The position and direction of electron beam were changed for $^{60}Co$ beam: $0^{\circ},\;5^{\circ}$ for 0cm seperation; $0^{\circ},\;5^{\circ},\;10^{\circ}$ for 0.5cm seperation; $5^{\circ},\;10^{\circ},\;15^{\circ}$ for 1cm seperation. The results are as followings. 1. When the seperation of two fields was increased, dose on the axis of $^{60}Co$ beam was increased and dose at the junction region decreased while the volume of lung to be exposed to high dose and hot spot size were irregularly changed. 2. The dose distribution in the target volume of internal mammary and chest wall was most ideal when the seperation of two fields was $0\~0.5cm$ and the direction of electron beam was parallel to $^{60}Co$ beam.

• 건축역사연구
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• 제21권1호
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• pp.135-154
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• 2012

The goal of this paper is to analyze the Freedom Center Apacle in Seoul designed by Kin Soo Geun who was a leading architect in Korean Modern architecture. Freedom Center was built in 1963, that was the largest monumental building to support military regime during cold war period in Korea. This paper deals with historical background of construction of Freedom Center and its characteristics compared to similar monumental buildings, especially Corbusier's Chandigar and Kenzo Tange's Hiroshima Peace Center. The Monumentality in Freedom Center came from the reference to these two buildings and its site plan. This paper tried to show how similar the layout of buildings between the Freedom Center and Peace Center. The origin of the sublime aura in Tange's linear layout of Peace Center is from Japanese Famous Shrine(Jinku). Kim translated it to serve the ideological purpose to protect from socialist regime in the name of freedom. Its over-scaled roof and weak contents showed Freedom center was a kind of theaterical setting belong to formalist building. But in spite of its symbolic and representational gesture its also had a architectonic physical quality to make it a monument. The change and duration in time testified the autonomous power of architecture in Freedom Center. Freedom Center was also important for using the exposed concrete and its superior finish. It was influenced not from western way of Benton Brut which was usually called New Brutalism but Japanese way of treating expose concrete. In spite of its limits Freedom center achieved new trend and sensibility in Korean Modern Architecture.

• 대한치과기공학회지
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• 제33권4호
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• pp.331-337
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• 2011

Purpose: The purpose of this study was to impact of force system change in finger spring that add helical coil one round on orthodontic force. Methods: The following conclusions were drawn from the experiment conducted after bending 90 samples with a CNC wire forming machine while changing the height and lumen size to 1mm - 3mm - 5mm and 2mm - 3mm - 4mm respectively in the coil of the force system in finger spring added with one wheel of helical coil of 18-8 stainless steel round wire (${\Phi}0.5mm$, spring hard) from Jinsung Co. in domestic market under the following conditions: Laboratory name = Instron 5942; Temperature($deg^{\circ}C$) = 18.00; Humidity(%) = 50.00; Rate 1 = 10.00000 mm/min; Compressive extension = 5.0mm. Results: When Coil height is 1, 3, 5mm and lumen size is 2, 3, 4mm reduce finger spring as mean value of compressive extension occasion maximum load(mN) increases as coil height rises, and lumen size grows to 5.0mm. And was expose that compressive load(mN) increases as coil position of finger spring rises and increase as lumen size is decrescent. Conclusion: As the adherence height of coil was raised from 1mm through 3mm to 5mm, compressive load increased. As the lumen size increased from 2mm through 3mm to 4mm, compressive load decreased. Therefore, these results suggest that it is desirable to lower the coil height and enlarge the lumen size to enhance the biomechanical efficiency of finger spring when manufacturing the finger spring for removable orthodontic devices.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제1권2호
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• pp.145-155
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• 1997

The effect of various supplies of lead singly and in combination with aluminium on growth and chlorophyll biosynthesis was investigated in 7-day-old Vigna angularis seedlings. Expose to 50 uM Pb or more drastically reduced root elongation rate. Significant depressions in root growth was observed within 1 day and no recovery of growth was seen over the duration of treatment period. Root elongation decreased depending on the Pb concentrations. Root growth inhibition was stronger than shoot growth inhibition. The initiation of lateral roots appeared to be more sensitive to Pb than the growth of main roots. Inhibition of root and shoot elongation by Pb was lessened by combined exposure of Pb and Al, suggesting that the presence of Al reverse the inhibitory effect of Pb alone. With the histochemical sodium rhodizonate method the rate of Pb uptake was dependent on the Pb concentration and exposure time of the roots to Pb salts. Pb was first deposited on the root surface and then translocated radially in the root cap cells. During a longer Pb administration (up to 72 h) Pb penetration was nonuniform, with accumulation within the cortex or endodermis. There was drastic reduction in chlorophyll content by Pb. The Pb inhibition of chlorophyll synthesis was concentration dependent. $\delta-Aminolevulinic$ acid dehydratase (ALAD) activity exhibited distinct inhibition from control. Reduction in chlorophyll content was accompanied by proportional changes in ALAD activity. Chlorophyll content and ALAD activity were less affected by combined exposure of Pb and Al, suggesting that Al has a protective effect against the inhibiting action of Pb on photosynthetic activity.

• 융합보안논문지
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• 제15권4호
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• pp.91-97
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• 2015

기업체에서는 정보를 암호화 후 저장하는 것을 법적으로 의무화하고 있다. 하지만, 실제로 정보를 암호화하여 저장하면 검색 또는 수정 시 서버에서 사전에 반드시 복호화 과정을 수행해야만 한다. 그러므로 처리지연 시간이 발생하고, 효율성이 떨어진다. 이러한 작업은 서버에 부담을 주게 되므로 서버를 관리하는 업체나 관리자는 정보를 암호화하여 저장하지 않는다. 본 논문에서는 네트워크 환경에서 정보의 수집과 빠른 의사결정을 복호화 과정 없이 암호문을 수정할 수 있는 준동형 연산을 이용하여 안전성이 보장되고 빠른 처리가 가능한 효과적인 보안 데이터 관리 시스템을 설계하고 구현한다. 구현된 시스템은 보안성의 보장을 위해 기존의 암호화 알고리즘을 사용할 수 있다. 검색 시에는 키워드 검색 방식을 사용한다. 추가로 트랩도어를 사용함으로써 키워드가 노출되지 않고 검색 시마다 변경되어 키워드에 대한 정보가 노출되지 않는다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권5호
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• pp.1977-1980
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• 2014

Background: The popularity of the narghile waterpipe, also referred to as hookah, shisha or hubble-bubble has increased tremendously during the past few decades. The aim of this study was to expose perception of narghile among a representative sample of university students in Sakarya University campus. Materials and Methods: Written approval was taken from the local education authority. An anonymous questionnaire which was prepared by the investigators and contained 17 questions was administered. Nine of the questions were related to socio-demographic characteristics and eight were related to the students harm perceptions about waterpipe. A total of 1,320 questionnaries were received and after preliminary evaluation 1,255 (95.7%) were found to be suitable for evaluation. The data was evaluated in SPSS program by using percentages and averages. Results: The $mean{\pm}SD$ age of the students was $20.8{\pm}2.29$ years (min 18, max 32). There were 864 (68.8%) females and 391 (31.2%) males. A total of 6.3 % of the students (n=79) believed that waterpipe is not harmful because its smoke does not burn the lungs. Almost one-third (n=318) think that the carcinogenic chemicals are filtered while waterpipe smoke passes from the water; 12.1 % of the students (n=152) checked "true" for the statement of "waterpipe smoke contains no nicotine". It is seen that 14.0 % of the students (n=176) think waterpipe with fruit/aroma is healthier than plain waterpipe. Conclusions: As a result of this study, it is found out that a substantial number of university students have false beliefs on harmful effects of waterpipe smoking.

• 대한관절경학회지
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• 제2권2호
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• pp.141-146
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• 1998

Recent studies suggest that most meniscal cysts can be treated surgically by arthroscopic management of the meniscal tear and arthroscopic cyst evacuation. But arthroscopic cyst decompression may sacrifice a substantial amount of meniscal tissue that is not torn in order to expose the "stalk" of the cyst. Nowadays, the trend is changing as preserving the involved meniscus to prevent from inevitable degenerative changes after meniscectomy. The purpose of this report is to describe a new surgical technique that minimizes loss of meniscal tissue in hopes of maximizing residual meniscal function. We experienced 10 patients with meniscal cysts that were consisted of four lateral cysts and six medial cysts. Menisci were torn in all cases. Arthroscopic partial meniscectomy and decompression of cysts were performed in 9 cases, and arthroscopic partial meniscectomy and open cystectomy in 1 case. The procedures were consisted of injection of the methylene blue into the cyst, partial meniscectomy of the meniscal tear until the dye was seen in orifice of the cyst, and decompression of cyst through cystic opening. This article serves to confirm the relationship between torn menisci and cysts, to re-evaluate the occurrence ratio of the meniscal cyst on the medial to lateral meniscus, and to assess the efficacy of arthroscopic partial meniscectomy and decompression of cyst as a potentially meniscal sparing procedure.