• 한국의학물리학회지:의학물리
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• 제32권4호
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• pp.130-136
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• 2021

Purpose: The Halcyon radiotherapy platform at Groote Schuur Hospital was delivered with a factory-configured analytical anisotropic algorithm (AAA) beam model for dose calculation. In a recent system upgrade, the Acuros XB (AXB) algorithm was installed. Both algorithms adopt fundamentally different approaches to dose calculation. This study aimed to compare the dose distributions of cervical carcinoma RapidArc plans calculated using both algorithms. Methods: A total of 15 plans previously calculated using the AAA were retrieved and recalculated using the AXB algorithm. Comparisons were performed using the planning target volume (PTV) maximum (max) and minimum (min) doses, D95%, D98%, D50%, D2%, homogeneity index (HI), and conformity index (CI). The mean and max doses and D2% were compared for the bladder, bowel, and femoral heads. Results: The AAA calculated slightly higher targets, D98%, D95%, D50%, and CI, than the AXB algorithm (44.49 Gy vs. 44.32 Gy, P=0.129; 44.87 Gy vs. 44.70 Gy, P=0.089; 46.00 Gy vs. 45.98 Gy, P=0.154; and 0.51 vs. 0.50, P=0.200, respectively). For target min dose, D2%, max dose, and HI, the AAA scored lower than the AXB algorithm (41.24 Gy vs. 41.30 Gy, P=0.902; 47.34 Gy vs. 47.75 Gy, P<0.001; 48.62 Gy vs. 50.14 Gy, P<0.001; and 0.06 vs. 0.07, P=0.002, respectively). For bladder, bowel, and left and right femurs, the AAA calculated higher mean and max doses. Conclusions: Statistically significant differences were observed for PTV D2%, max dose, HI, and bowel max dose (P>0.05).

• 한국경영과학회지
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• 제22권2호
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• pp.13-29
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• 1997

This paper considers a new routing problem, successive max-min connection ratio problem (SMCRP), arised in circuit telecommunication networks such as SONET and WDM optical transport network. An optimization model for SMCRP is established based on link-flow formulation. It's first optimization process is an integral version of maximum concurrent flow problem. Integer condition does not give the same connection-ratio of each node-pair at an optimal solution any more. It is also an integral multi-commodity flow problem with fairness restriction. In order to guarantee fairness to every node-pair the minimum of connection ratios to demand is maximized. NP- hardness of SMCRP is proved and a heuristic algorithm with polynomial-time bound is developed for the problem. Augmenting path and rerouting flow are used for the algorithm. The heuristic algorithm is implemented and tested for networks of different sizes. The results are compared with those given by GAMS/OSL, a popular commercial solver for integer programming problem.n among ferrite-pearlite matrix, the increase in spheroidal ratio with increasing fatigue limitation, 90% had the highest, 14.3% increasing more then 70%, distribution range of fatigue.
ife was small in same stress level. (2) $\sqrt{area}_{max}$ of graphite can be used to predict fatigue limit of Ductile Cast Iron. The Statistical distribution of extreme values of $\sqrt{area}_{max}$ may be used as a guideline for the control of inclusion size in the steelmaking.

• 약학회지
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• 제43권6호
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• pp.834-842
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• 1999

The metabolism and pharmacokinetics of M-l, which is metabolite of pentoxifylline, have been studied in human liver microsomes. Biphasic kinetics was observed from the Eadie-Hofstee plot for the formation of both metabolites of M-l. For the kinetics of pentoxifylline, mean values of $V_{max1}{\;}and{\;}V_{max2}$ were 1,648 and 5,622 nmol/min/mg protein, and the estimated values of $K_{ml}{\;}and{\;}K_{m2}$ were 0.180 and 4.829 mM, respectively. For M-3, mean values of $V_{max1}{\;}and{\;}V_{max2}$ were 0.062 and 0.491 nmol/min/mg protein, and estimated values of $K_{ml}{\;}and{\;}K_{m2}$ were 0.025 and 1.216 mM. The formations of pentoxifylline and M-3 from M-1 were indentified by using several selective inhibitors of cytochrome P450 isoformes at 0.05-5 mM concentration of M-1 in human liver microsomes. For the analysis of low (0.05 mM) concentration of M-1, where the affinity was expected as low, indicated that CYPlA2 and CYP3A4 were major P450 isoforms responsible for pentoxifylline and M-3 formation. CYP3A4 and CYP2A6 appeared to be P450 isoforms responsible for M-3 formation at high (5 mM) concentration of M-1.

• 한국항행학회논문지
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• 제18권5호
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• pp.461-467
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• 2014

AQM은 라우터에서 사용되고 있으며 큐의 순간적 길이나 평균길이를 관찰하여 혼잡을 예측하고 탐지하는 알고리즘이며, 평균 큐길이가 임계 값을 초과하면 혼잡이 발생하였다고 추론하고 라우터로 유입되는 패킷을 미리 폐기시키거나 패킷 전송 노드에게 혼잡을 미리 알림으로써 전송노드에서 전송률을 줄여 혼잡을 피하도록 한다. AQM 알고리즘의 하나인 RED (random early detection)는 패킷을 무작위로 폐기시켜 혼잡제어를 하는 큐 기반의 혼잡 제어기술이다. RED는 TCP의 시간경과 및 큐 지연을 줄이며 링크 활용도를 높이고 버스트한 트래픽이 유입되는 것을 관리하는 기술로써 널리 사용되어지고 있으며 혼잡도의 정도를 큐의 평균 길이로 추정한다. 그러나 파라미터($P_{max}$, $TH_{min}$)값들이 고정되어 있어서 특정한 네트워크 환경에서는 동작을 잘 못한다. 본 논문에서는 네트워크 상태를 지속적으로 감지함으로써 $P_{max}$와 $TH_{min}$의 값을 네트워크 상태에 적합한 값으로 자동적으로 바꾸어줌으로서 다양한 환경에서도 동작을 잘할 수 있는 확장 RED를 제안한다.

• 한국대기환경학회지
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• 제24권4호
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• pp.393-403
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• 2008

In an effort to estimate secondary $PM_{10}$ concentrations and their diurnal variations at different photochemical activities, $PM_{10}$, CO, and $O_3$ concentrations obtained from the ambient air quality network located in Seoul are analyzed for the period from 2000 to 2005. In order to classify the photochemical activities on a daily basis, measured ${\Delta}O_{3,\;max-min}$ (maximum $O_3$-minimum $O_3$) and ${\int}(hv)dt$ which represents accumulated daily insolation, were used to classify each day into three regimes: 1) low photochemical reactivity; ${\Delta}O_{3,\;max-min}\;{\leq}\;40\;ppb$, and ${\int}(hv)dt\;{\leq}\;4000\;W/m^2$, 2) moderate photochemical reactivity; $40\;ppb\;<\;{\Delta}O_{3,\;max-min}\;{\leq}\;60\;ppb$, and $4000\;{\leq}\;{\int}(hv)de\;{\leq}\;6000\;W/m^2$, and 3) high photochemical reactivity; ${\Delta}O_{3,\;max-min}\;>\;60\;ppb$, and ${\int}(hv)dt\;{\geq}\;6000\;W/m^2$. The ratio of ($PM_{10}$/CO) obtained at low photochemical activity regime was used as an index of tracer for the estimation of secondary $PM_{10}$ at higher photochemical activity regimes. The results show that the estimated secondary $PM_{10}$ concentrations for moderate and high photochemical regimes are found to be 18.8% ($10.9\;{\mu}g/m^3$), and 35.0% ($26.2\;{\mu}g/m^3$), respectively. Diurnal variation of secondary $PM_{10}$ for the moderate photochemical regime shows weak but noticeable patterns. However, the highly activated photochemical regime shows strong diurnal variations of secondary $PM_{10}$ concentrations with the maximum value of $35.1\;{\mu}g/m^3$ at 1300LST.

• 약학회지
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• 제40권4호
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• pp.400-410
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• 1996

In oder to develop the controlled release of drugs from the suppositories, in vitro drug release and in vivo absorption in rabbits were investigated. Various suppo sitory forms with hollow cavities, into which drugs in the form of fine powder or solid dispersion system(SDS) could be placed, were utilized. The oleaginous Witepsol H-15 (WH-15) as a base, and indomethacin (IDM) of a very slightly soluble drug and propranolol-HCL (PPH) of a very soluble drug were employed as model drugs. The in vitro drug release showed that the cumulative release amount of PPH from PPH-(methylcellulose) MC-SDS and PPH-(ethylcellulose) EC-SDS hollow type suppositories reached 40% and 12% in 6 hrs,respectively. On the other hand, the drug release for a conventional suppository was 80% in 6 hrs. For the IDM suppositories,the cumulative drug release from IDM-(polyvinylpyrrolidone) PVP-SDS hollow type suppositories reached 99% in 24 hrs, whereas that from a conventional suppository reached 85%. An in vivo experiment with rabbits showed that IDM-PVP-SDS hollow type suppository delayed the absorption of IDM, significantly. The $t_{max},\;C_{max}\;and\;AUC_{0{\to}8}$ of IDM-PVP-SDS suppository were 60 min, 12.12${\mu}g$/ml and 2657${\mu}g$/ml/min, respectively. The $t_{max},\;C_{max}\;and\;AUC_{0{\to}8}$ of controlled group were 20 min, 15.49${\mu}g$/ml and 2190${\mu}g$/ml/min, respectively.

• 전기전자학회논문지
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• 제8권1호
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• pp.33-38
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• 2004

다치 논리 패스 게이트는 다치 논리를 구성하기 위한 중요한 소자이다. 본 논문에서는, 뉴런 $MOS({\nu}MOS)$ 임계 게이트를 갖는 2중 패스-트랜지스터 논리를 이용하여 4치 MIN(QMIN)/negated MIN(QNMIN) 게이트 그리고 4치 MAX(QMAX)/negated MAX(QNMAX) 게이트를 설계하였다. DPL은 입력 캐패시턴스의 증가 없이 게이트 속도를 향상 시켰다. 또한 대칭 배열과 2중 전송 특성을 갖는다. 임계 게이트는 ${\nu}MOS$ 다운 리터럴 회로(DLC)로 구성 된다. 제안된 게이트는 다양한 다치 임계 전압을 실현할 수 있다. 본 논문에서, 회로는 3V의 전원 전압을 사용하였고 0.35um N-Well 2-poly 4-metal CMOS 공정의 파라메터를 사용하였으며 모든 모의 실험은 HSPICE를 이용하였다.

• 한국통신학회논문지
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• 제38A권8호
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• pp.644-649
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• 2013

광기록 정보저장장치에서 인코딩된 시퀀스의 DC-억압을 위해 Guided Scrambling 기법이 널리 사용된다. 후보 코드시퀀스 중 최적의 DC-억압 코드를 선택하기 위해 digital sum value (DSV)의 함수로 정의된 기준을 사용한다. 이 중 minimum DSV (MDSV), minimum squared weight (MSW), minimum threshold overrun (MTO) 등이 널리 사용된다. 본 연구에서는 MDSV, MSW, MTO 기준을 채택하는 GS 코딩 알고리즘과 동등한 정수계획법 모형을 제안한다. 개발된 MDSV 정수계획법 모형을 MaxMin 형태의 모형으로 확장하여 스크램블링 다항식과 제어 비트에 따른 MDSV GS 코딩의 최악 성능을 평가할 수 있는 모형을 개발하였다. 모의실험에서는 다수의 스크램블링 다항식 및 제어비트 조합에 대하여 MDSV 최악 성능을 계산하였다.

• 대한임상검사과학회지
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• 제46권4호
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• pp.117-123
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• 2014

Creatinine is a general marker as a screening test for renal disease. This study was conducted to provide basic data about pediatric concentration for serum and urine creatinine. The data from the 2011 Korean National Health and Nutrition Examination Survey was used. Analysis was done on 488 Children and Adolescents (boys 278, girls 210) aged 10 to 19, the Jaffe reaction method was used to gather the data. The highest serum creatinine levels were found in boys aged 19 to 20 years, the mean being 0.97 mg/dL (min 0.81 mg/dL, max 1.14 mg/dL). The levels showed increase over those in the 10 year old group. The highest urine creatinine levels were found aged 19 to 20 years, and the mean was 222.68 mg/dL (min 133 mg/dL, max 324 mg/dL). In the case of girls, the highest serum creatinine levels were found with those aged between 18 and 19, the mean being 0.71 mg/dL (min 0.49 mg/dL, max 0.84 mg/dL). The levels showed increase over the 11 to 18 year old group. The highest urine creatinine levels were found aged 14 to 15 years, and the mean was 218.44 mg/dL (min 131 mg/dL, max 321 mg/dL). The mean difference in serum creatinine in all age groups was statistically significant except for those aged 10 to 14, that of urine creatinine in all age groups was not significant statistically except for those aged 12 to 13, 17 to 18. Therefore, it is suggested that reference values for children and adolescents should be divided into different groups according to gender, further studies are needed using complementing data of the pediatrics.

• 한국정보과학회논문지:소프트웨어및응용
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• 제34권6호
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• pp.572-583
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• 2007

본 논문에서는 자연스러운 텍스트 생성을 위한 여러 과정 중, 문장 순서를 결정하기 위한 텍스트 구조화(text structuring)에 관한 것으로, 중심화 이론(centering theory)에 기반하여 문장 순서의 자연스러움을 판단할 수 있는 다양한 평가 척도를 논의한다. 먼저, 기존 연구들에서 중심화 이론에 기반한 문장 순서의 평가 척도들 중 가장 효과적이라고 알려진 MIN.NOCB를 텍스트 구조화에 적용할 때 발생할 수 있는 문제점을 지적하고, 대안이 될 수 있는 새로운 평가 척도인 MAX.CPS를 제안한다. 또, 임의의 평가 척도가 주어진 문장들에 대해 가질 수 있는 기대치를 먼저 예측하고, 그것에 따라 다른 평가 척도를 적용하게 하는 프레임워크를 제안하여, 중심화 이론 안에서 최상의 문장 순서를 찾기 위한 새로운 방법론을 모색한다. 또한, 중심화 이론의 적용에 있어 핵심이라 할 수 있는, 명사들의 돋보임성(salience)을 서열화(cf-ranking) 하는 다양한 방식을 중심화 기반 문장 순서 평가 척도의 관점에서 분석하였다. 그 결과, 텍스트 구조화에 관한 한, 단순히 문장에서 실현된 순서에 따라 명사들의 돋보임성의 서열을 정하는 것이 한국어의 특성상 가장 간단하면서도 효율적임을 입증하였다.