• 한국정보과학회논문지:소프트웨어및응용
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• 제32권5호
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• pp.335-345
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• 2005

개인화된 마케팅에서 고객 만족과 마케팅 효율을 최대화하는 것은 중요하다. 개인화된 캠페인이 수행됨에 따라 여러 캠페인이 동시에 수행되곤 한다. 이 논문에서 우리는 동시에 여러 개인화된 캠페인을 수행할 때 발생하는 중복 추천 문제를 제기한다. 이는 특정 고객에게 상당히 많은 양의 캠페인이 쏟아지게 되는 문제를 말한다. 이 이슈를 해결하기 위한 다중캠페인 할당 문제를 모델링 한다. 그리고 이 문제의 해결 방법으로 동적계획법을 비롯한 여러 휴리스틱 알고리즘들을 제안한다. 필드 데이타의 실험을 통해 제기된 문제 모델의 중요성과 제안된 알고리즘의 효율성을 입증한다.

• 한국정보과학회논문지:컴퓨팅의 실제 및 레터
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• 제14권4호
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• pp.431-435
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• 2008

기존의 CDP(Congestion Driven Placement) 기법[1]은 배선 밀집도에 크게 기여하는 넷에 속한 모든 셀들을 옮길 때 가능한 방향을 모두 고려하기 때문에 CPU 시간을 많이 소모한다. 본 논문에선 배선 밀집도를 완화하기 위한 빠른 배치 기법, 즉 ICDGP(Improved Congestion Driven Global Placement)라 불리는 개선된 기법을 제안한다. ICDGP는 밀집된 지역에 있는 넷에 속한 셀들의 이동 목표 지점을 정하기 위해 force-directed 기법을 사용하며, 각 셀은 이동 목표 지점으로만 옮기는 것을 고려한다. ICDGP는 또한 셀을 하나씩 옮기는 것보다 다수의 셀을 동시에 같이 옳기는 것이 낫다고 판단되면 같이 옮긴다. 실험 결과에 의하면 CDP보다 ICDGP가 배선 밀집도 면에서 좋은 배치를 생성한다. 특히 CPU 시간은 평균 36% 개선되었다.

• Archives of Plastic Surgery
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• 제47권3호
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• pp.256-262
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• 2020

Background Most women consider an oval-shaped face to be youthful and beautiful. In recent years, demand has grown for surgical procedures with a shorter downtime and fewer complications. These minimally invasive procedures include botulinum toxin type A (BoNTA) injection, filler injection, suction-assisted liposuction (SAL), laser-assisted lipolysis (LAL), thread lifting, and fat grafting. This study aims to introduce an effective method for creating an aesthetically pleasing lower face using a combination of minimally invasive procedures. Methods From March 2017 to March 2019, 94 patients simultaneously underwent LAL, SAL, and thread lifting. Ancillary procedures such as BoNTA injections, hyaluronic acid filler injections, and removal of the buccal fat pad (BFP) were selectively performed according to the patient's condition. Results Patients rated their postoperative satisfaction as very satisfied, satisfied, dissatisfied, or very dissatisfied. Approximately 83% of all respondents were satisfied with the results, whereas the remaining respondents had complaints regarding the outcomes. The most common reasons for dissatisfaction were a longer-than-expected recovery time and undercorrection, and the most severe complaint was skin depression as a result of overcorrection. Conclusions Our method of simultaneously performing LAL, SAL, and thread lifting, while adding BoNTA, filler injections, and BFP removal as needed, was capable of producing consistent and reliable aesthetic outcomes for the lower face.

• Tribology and Lubricants
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• 제33권6호
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• pp.296-302
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• 2017

Ball milling of elemental powders in advance and using an induction heating system for intermetallic coatings are known to enhance the reactivity of combustion synthesis. In this work, the effects of simultaneously applying these two incentive methods on the properties of intermetallic coatings are studied. Ni-Al powder compacts ball-milled with three different ball-to-powder weight ratio mixtures are synthesized and coated on mild steel by combustion synthesis in an induction heating system. Consequently, similar to an electrical heating system, the positive effects of ball milling on the combustion synthesis are confirmed in the induction heating system. The enhancement in synthetic reactivity achieved by applying the two incentive methods at the same time is greater than that by applying each incentive method separately. In particular, the enhancement is remarkable at low reaction temperature. However, there are limitations to improving the reactivity by simultaneously applying the two incentive methods to the combustion synthesis, unlike the reaction temperature. The microstructure and hardness of the coating layer are both influenced by the ball-charging ratio employed in the ball-milling process.

• 대한수의학회지
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• 제37권3호
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• pp.509-523
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• 1997

This study was carried out for investigating antitumor effects of 5-fluorouracil(5-FU), methotrexate(MTX) and retinoic acid(RA) on hepatocellular carcinoma induced in Sprague-Dawley rat. Antitumor effects were examined a flow cytometric DNA distributions by flow cytometry and stuied ATP/Pi using nuclear magnetic resorance, and the enzymatic activity of thymidylate synthetase and dihydrofolate reductase as well as contents of total collagen and sialic acid were measured with spectrophotometer. In this study, S phase fraction, contents of sialic acid and total collagen were decreased in the induced hepatocellular carcinoma treated with 5-FU and MTX, and synergistic effects of anticancer drugs were exhibited in the hepatocellular carcinoma treated with 5-FU and MTX simultaneously, and the inhibition of thymidylate synthetic and dihydrofolate reductase activity were shown in the hepatocellular carcinoma treated with 5-FU, MTX, and 5-FU and MTX simultaneously. On the other hand, the ratio of ATP/Pi were increased in all groups except group treated with RA. The experimental results suggest that above method may be valuable for evaluating antitumor effect of anticancer drugs.

• 상하수도학회지
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• 제27권6호
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• pp.743-750
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• 2013

In this study, the carbonized aggregate of light weight and high mechanical strength using sewage sludge was evaluated with changing carbonation variables of temperature, detention time and feed condition. Porosity and mechanical strength was simultaneously increased according to increase of carbonization temperature unexpectedly. Carbonization detention time above 1 hour nearly affect on the porosity, but mainly on mechanical strength of the carbonized aggregate in case of clay addition. On $900^{\circ}C$, porosity and mechanical strength was increased rapidly, but above $1000^{\circ}C$, porosity began to decrease. Clay addition was very effective on increase of mechanical strength following much loss in porosity. The carbonized aggregate manufactured at $900^{\circ}C$ adding 30 % clay in sewage sludge was higher a little in porosity and 3 times in mechanical strength than those at $700^{\circ}C$ not adding clay. Consequently, in manufacturing the carbonized aggregate having simultaneously high porosity and mechanical strength, it is desirable to have operational condition of $900{\sim}1000^{\circ}C$ temperature and 1 hour time, and clay addition within 30 % for further higher mechanical strength.

• 대한기계학회논문집
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• 제10권5호
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• pp.742-750
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• 1986

본 연구에서는 레일의 불규칙성을 가우시안 분포(Gausian distribution)를 갖 는 랜덤함수로 보고 레일과 바퀴의 비선형기하학적 형상을 확률적 선형화 방법으로 단 순화하여 측방향 강제진동 응답을 구하였다. 또 구하여진 rms 응답 스펙트럼은 비선 형 방정식을 직접 수치적분하여 구한 결과와 비교하므로써 확률적 선형화방법의 효용 성을 보였다. 또한 열차 주행 속도를 변화 시키면서 강제 진동 응답을 시간 영역에 서 구하였으며 그로부터 지금까지 실험결과에서 나타나고 있는 간헐적헌팅(intermit- tent hunting)에 대한 현상을 설명하였다.

• 한국자동차공학회논문집
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• 제9권4호
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• pp.1-9
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• 2001

The soot yield has been studied by a premixed propane-oxygen-inert gas combustion in a specially designed disk-type constant-volume combustion chamber to investigate the effects of pressure, temperature and turbulence on soot formation. Premixtures are simultaneously ignited by eight spark plugs located on the circumference of chamber at 45 degree intervals in order to observe the soot formation under high pressures. The eight flames converged compress the end gases to a high pressure. The laser schlieren and direct flame photographs for observation field with 10 mm in diameter are taken to examine into the behaviors of flame front and gas flow in laminar and turbulent combustion. The soot volume fraction in the chamber center during the final stage of combustion at the highest pressure is measured by the in situ laser extinction technique and simultaneously the corresponding burnt gas temperature by the two-color pyrometry method. The pressure and temperature during soot formation are changed by varying the initial charge pressure and the volume fraction of inert gas compositions, respectively. It is found that the soot yield increases with dropping temperature and rising pressure at constant equivalence ratio, and that the soot yield of turbulent combustion decreases in comparison with that of laminar combustion because the burnt gas temperature increases with the drop of heat loss.

• 한국자동차공학회논문집
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• 제12권4호
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• pp.24-30
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• 2004

As the environmental pollution becomes serious global problem, the regulation of emission exhausted from automobiles is strengthened. Therefore, it is very important to know how to reduce the NOx and PM simultaneously in diesel engines, which has lot of merits such as high thermal efficiency, low fuel consumption and durability. By this reason, the new concept called as Homogeneous Charge Compression Ignition(HCCI) engines are spotlighted because this concept reduced NOx and P.M. simultaneously. However, there is trade off between output and NOx in a HCCI engine. In this study, output and emission characteristics for a gasoline direct injection type HCCI engine were investigated to clarify the effects of intake air temperature, injection time and mixture formation. From these experiments, we found that the smoke was not produced when the fuel was injected earlier than BTDC 90$^{\circ}$. In addition, the output was increased because of delay of ignition time and NOx emission was decreased because of homogeneous charge of first injection in case of split injection.

• Childhood Kidney Diseases
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• 제7권1호
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• pp.77-81
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• 2003

설사연관형 용혈성 요독 증후군은 수술적 치료가 필요한 외과적 합병증이 드물게 동반된다. 저자들은 급성 출혈성 장염으로 진단된 후 동시에 설사 연관형 용혈성 요독 증후군과 급성 충수염으로 진행한 1례를 경험하였기에 보고하는 바이다.