• International Journal of Reliability and Applications
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• 제1권1호
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• pp.27-38
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• 2000

In a recent paper Iskandar ＆ Sandoh (1999) studied an opportunity-based age replacement policy for a system which has a warranty period (0,S]. When the system fails at age x $\leq$ S a minimal repair is performed. If an opportunity occurs to the system at age x, S $\leq$ x $\leq$ T, we take the opportunity with probability p to preventively replace the system, while we conduct a corrective .replacement when its fails in (S,T). Finally, if its age reaches T, we perform a preventive replacement, Under this policy the design variable is T. For the case when opportunities occur according to a homogeneous Poisson process, the long-run average cost of this policy was formulated and studied analytically by Iskandar & Sandoh (1999). The same problem is here analysed by using a graphical technique based on scaled TTT-transforms. This technique gives, among other things, excellent possibilities for different types of sensitivity analysis. We also extend the discussion to the situation when we have to estimate T based on times to failure.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
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• pp.59-62
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• 2003

This study investigated the phase transformation of the $REBa_2Cu_3O_{7-x}$ (RE=Nd, Gd, By) superconductor, and CCT (Continuous-Cooling-Transformation) along with the TTT (Time-Temperature-Transformation) diagrams are suggested according to the isothermal and continuous cooling heat-treatments. According to result of fabricated single crystal of RE-123 superconductor through TSMG method based on phase transformation neted among heat treatment process, when the ionic radius elements was decreased, RE-211 phase was well-distributed. According to result that examine about seed of pretreatment effect of TSMG method, magnetic hysteresis improved when preprocess among oxygen atmosphere in same seed. and used after. Effect of miscut expressed good superconducting special quality in case miscut uses big seed.

• 한국안광학회지
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• 제9권2호
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• pp.301-312
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• 2004

본 연구는 콘택트렌즈 착용자와 건성안 환자 사이의 관계를 비교하기 위해 시행되었다. 콘택트렌즈 착용자와 건성안 환자의 눈물 양과 질 및 안구 표면 상태와 자각증상을 조사하기 위해 TBUT, SIT, TIT, Rose-bengal staining and McMonnies dry eye symptom questionnaire를 시행하였다. 조사 대상자는 108명으로 3부류로 나누었는데 건성안 의심자 35명, 콘택트렌즈 착용자 38명, 대조군 35명이었다. 콘택트렌즈 착용자는 3그룹으로 나누었는데 12개월 이하, 13-48개월 이만, 48개월 이상으로 구분하였다. 본 연구 결과 시행한 모든 조사에서 콘택트렌즈 착용자와 건성안 환자 사이에 큰 차이가 없는 것으로 밝혀졌으며 콘택트렌즈 착용으로 건성안이 유도됨을 알 수 있었다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권18호
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• pp.7805-7809
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• 2014

Objective: To explore the clinical efficacy and prognostic factors of chemoreduction combined with topical treatment of advanced intraocular retinoblastoma (RB). Materials and Methods: A total of 22 eyes from 17 children with RB were selected for the study and treated with chemoreduction combined with topical cryotherapy, transpupillary thermotherapy (TTT) or episcleral plaque brachytherapy. Clinical and follow-up data were retrospectively analyzed. Results: All children received 2~6 courses of chemoreduction treatment, ($4.5{\pm}0.8$ courses on average); 17 eyes from 13 children were treated by chemoreduction combined with cryotherapy or TTT and 5 eyes from 4 children with chemoreduction combined with $^{125}I$ episcleral plaque brachytherapy. The eye retention rate was 81.8% (18/22), among which 38.9% (7/18) featured restored or maintained good vision. Postoperative follow-up period was 7 to 34 months, ($18.6{\pm}5.2$ months on average). The recurrence rate was 41.2% (7/17), among which 57.1% (4/7) were controlled by supplementing or appending cryotherapy or TTT treatment during the follow-up period. The tumor basal diameter and thickness were significantly reduced (P<0.05 or P<0.01) after treatment. All children demonstrated different degrees of hair loss, 70.6% (12/17) with different degrees of gastrointestinal reactions, 5.88% (1/17) with neutropenia and 11.8% (2/17) being seriously infected during the chemotherapeutic treatment. Univariate and logistic regression analysis showed that tumor basal diameter before treatment had a significant effect on the prognosis (P<0.01). Conclusions: Chemoreduction combined with topical therapy can effectively control RB in the short term, and tumor basal diameter before treatment is an independent risk factor for prognosis.

• 한국자원식물학회지
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• 제31권5호
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• pp.531-537
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• 2018

국내 재배종 마늘을 대상으로 상처(wound) 처리에 특이적으로 발현되는 Cyt. P450 cDNA (ORF 1,419 bp) 중 1,210~1,240 bp 사이에 존재하는 heme-binding domain (HB-domain)의 염기서열 다형성을 바탕으로 국내산 재배마늘의 HB-domain의 다형성 분포를 조사하였다. 국내 재배마늘에서 7개의 각각 다른 염기서열을 가진 HB-domain 마커를 탐색하였고, 전국 6개 지역의 재배농가에서 임의로 수집한 120개 마늘의 마커 종류별 분포도를 조사하였다. 경북, 충남, 충북, 강원지역에서 재배되는 한지형 마늘은 아미노산서열 FGGGRRICPG, DNA서열 5'-TTT/GGC/GGT/GGA/CGG/AGA/ATA/TGT/CCT/GGA-3'인 KP2형의 HB-domain을 가진 재배종이 51.3%로 가장 많이 분포하였고, KP1형 13.7%, CP형 11.3%, CM형 8.8%, KW2형 5% 및 기타 1.3%인 것으로 나타났다. 경남지역 재배지에서 수집한 난지형 마늘은 아미노산서열 FGAGRRICPG, DNA서열 '5-TTT/GGC/GCA/GGA/CGG/AGA/ATT/TGT/CCT/GGA-3'인 KM형이 52.5%로 가장 많았고, KP2형 22.5%, KW2형 5%, KP1 및 CP형이 각각 2.5%가 분포하는 것으로 나타났으나 CM형은 존재하지 않았다. 이 결과는 우리나라에 재배되는 마늘은 유전적으로 상당히 혼재된 상태로 존재하며, 특정 지역을 대표하는 유전적 특징을 가진 재배종을 단정하기는 어려운 것으로 판단된다.

• 한국식품영양학회지
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• 제11권1호
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• pp.26-30
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• 1998

옥수수 기름의 탈취온도가 trans 지방산 생성량 및 그 조성에 미치는 영향을 GLC를 이용하여 측정하였다. 상대적으로 저온탈취인 240~25$0^{\circ}C$에서는 극미량의 trans 지방산만이 검출되었으나, 고온탈취인 255~27$0^{\circ}C$ 구간에서는 0.30, 0.57, 0.64 및 0.81%를 나타내었다. 이성화 현상은 이중결합수가 증가할수록 두드러졌으며, tt 및 ttt형은 거의 검출되지 않았는데 비하여 ct, cct 및 tcc형이 다량 검출되었다. 따라서, 탈취유의 이화학적 특성과 함께 이성체형성의 극소화는 저온탈취에 의하여 최대의 효과를 얻을 수 있음을 확인하였다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2004년도 춘계학술대회 논문집
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• pp.395-399
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• 2004

Four microalloyed steels containing B were investigated in terms of hardenability, mechanical properties and microstructure depending upon the cooling rates in order to develop the steel grade for the cold forged fasners. The alloy with the largest DI value among 4 alloys, which contains $0.12\%\;C,\;1.54\%\;Mn,\;0.65\%\;Cr,\;0.11\%V,\;0.040\%Ti\;and\;0.0033\%B$, showed the larest shift to the right hand side in the TTT diagram, implying the wide allowable cooling rate range subsequent to hot rolling in long bar processing, Mechanical tests indicated that yield strength are dependent upon the DI value in water quenched specimens but other properties showed almost the same values. In the same grade of steel, the increase in cooling rates causes the decrease in elongation but the increase in strength, reduction of area and Charpy impact values. Microstructural examination in steel grade with the larest DI values revealed martensitic structure In the water quenched state, a mixture of martensite and bainite in the oil quenched, and ferrite + pearlite in the air cooled and the forced air cooled but the latter showed finer microstructure.

• 한국세라믹학회지
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• 제43권4호
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• pp.242-246
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• 2006

[ ${\alpha}-Al_2O_3$ ] nanopowders were fabricated by the thermal decomposition and synthetic of Ammonium Aluminum Carbonate Hydroxide (AACH). Crystallite size of 5 to 8 nm were fabricated when reaction temperature of AACH was low, $8^{\circ}C$, and the highest $[NH_4{^+}][AlO(OH)_n{(SO_4){^-}}_{3-n/2}][HCO_3]$ ionic concentration to pH of the Ammonium Hydrogen Carbonate (AHC) aqueous solution was 10. The phase transformation fem $NH_4Al(SO_4)_2$, rhombohedral $(Al_2(SO_4)_3)$, amorphous-, ${\theta}-,\;{\alpha}-Al_2O_3$ was examined at each temperature according to the AACH. A Time-Temperature-Transformation (TTT) diagram for thermal decomposition in air was determined. Homogeneous, spherical nanopowders with a particle size of 70 nm were obtained by firing the 5 to 8 m crystallites, which had been synthesized from AACH at pH 10 and $8^{\circ}C,\;at\;1150^{\circ}C$ for 3 h in air.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권8호
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• pp.4061-4076
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• 2017

With the development of high-speed railway technologies, train velocities can now reach speeds up to 350 km/h, and higher in the future. In high-speed railway systems (HSRs), loss of communication can result in serious accidents, especially when the train is controlled through wireless communications. For to this reason, operators of Long Term Evolution for Railway (LTE-R) communication systems install eNodeBs (eNBs) with high density to achieve highly reliable communications. However, densely located eNBs can result in unnecessary frequent handovers (HOs) resulting in instability because, during every HO process, there is a period of time in which the communication link is disconnected. To solve this problem, in this paper, an HO scheme based on the maximum cell residence time (CRT) and adaptive time to trigger (aTTT), which are collectively called CaT, is proposed to reduce unnecessary HOs (using CRT estimations) and decrease HO failures by improving the handover command transmission point (HCTP) in LTE-R HSR communications.

• 한국임상수의학회지
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• 제36권5호
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• pp.285-288
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• 2019

A 5-year-old 6 kg male mongrel (case 1) and a 7-year-old 4.3 kg male yorkshire terrier (case 2) were presented to Chonbuk animal medical center (CAMC). Both animals had non-weight bearing hind limb lameness. Case 1 had complete rupture of cranial cruciate ligament with grade 3 medial patellar luxation. Case 2 had complete cranial cruciate ligament rupture with grade 4 medial patellar luxation. During surgery, in both cases, trochlear block recession was performed followed by CORA based leveling osteotomy (CBLO) and tibial tuberosity transposition (TTT). General soft tissue reconstructions for medial patellar luxation including medial releasing and lateral imbrication were also performed. Postoperatively, both animals demonstrated excellent recovery and regained normal weight bearing of the affected hind limb without any recognizable complication. CBLO followed by TTT can be a curative surgical option without complications in cases of cranial cruciate ligament rupture with high-grade medial patellar luxation in small breed dogs.