• 한국정보과학회논문지:시스템및이론
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• 제30권3_4호
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• pp.168-185
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• 2003

본 논문은 하나의 스케치 면도인 선화로부터 면 인식의 탐색 영역을 축소하고 다양한 3차원 물체를 빠르게 복원하는 점진적인 알고리즘을 제안한다. 복원 과정의 입력으로 사용되는 스케치 면도는 파선이 제거되지 않은 모서리-꼭지점 그래프인 2차원 스케치 면도로서 3차원 와이어프레임 물체의 부정확한 free-hand 스케치이다. 알고리즘은 두 단계로 수행된다. 면 인식 단계에서는 스케치 면도로부터 모든 가능 한 면을 생성하고 탐색 공간을 축소하기 위한 기하학적 위상학적 제약 조건을 이용하여 면을 불가능한 면, 기본 면, 최소 면으로 분류한다. 제안 알고리즘은 물체를 구성하는 실제 면을 빠르게 인식하기 위하여 최소 면만을 탐색한다 물체 생성 단계에서는 면의 스케치 순서에 따라 물체의 꼭지점 좌표를 최적화함으로써 3차원 구조를 점진적으로 계산한다. 점진적 방법은 복원 과정에서 물체와 스케치 도면 사이의 관계로부터 유도된 3차원 제약 조건을 적용함으로써 최적 3차원 물체를 빠르게 복원한다. 또한, 스케치 도중에 시점 이동을 허용한다. 점진적 복원 알고리즘을 기술하고 실제 구현 결과를 보인다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권22호
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• pp.9673-9678
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• 2014

Background: Breast cancer is a fatal disease and the most frequently diagnosed cancer in women with an increasing pattern worldwide. The burden is mostly attributed to metastatic cancers that occur in one-third of patients and the treatments are palliative. It is of great interest to determine factors affecting time from cancer diagnosis to secondary metastasis. Materials and Methods: Cure rate models assume a Poisson distribution for the number of unobservable metastatic-component cells that are completely deleted from the non-metastasis patient body but some may remain and result in metastasis. Time to metastasis is defined as a function of the number of these cells and the time for each cell to develop a detectable sign of metastasis. Covariates are introduced to the model via the rate of metastatic-component cells. We used non-mixture cure rate models with Weibull and log-logistic distributions in a Bayesian setting to assess the relationship between metastasis free survival and covariates. Results: The median of metastasis free survival was 76.9 months. Various models showed that from covariates in the study, lymph node involvement ratio and being progesterone receptor positive were significant, with an adverse and a beneficial effect on metastasis free survival, respectively. The estimated fraction of patients cured from metastasis was almost 48%. The Weibull model had a slightly better performance than log-logistic. Conclusions: Cure rate models are popular in survival studies and outperform other models under certain conditions. We explored the prognostic factors of metastatic breast cancer from a different viewpoint. In this study, metastasis sites were analyzed all together. Conducting similar studies in a larger sample of cancer patients as well as evaluating the prognostic value of covariates in metastasis to each site separately are recommended.

• Structural Engineering and Mechanics
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• 제21권6호
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• pp.713-735
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• 2005

Due to the complexity of mathematical expressions, the literature concerning the free vibration analysis of plates carrying multiple three-degree-of-freedom (dof) spring-mass systems is rare. In this paper, the three degrees of freedom (dof's) for a spring-mass system refer to the translational motion of its lumped mass in the vertical ($\bar{z}$) direction and the two pitching motions of its lumped mass about the two horizontal ($\bar{x}$ and $\bar{y}$) axes. The basic concept of this paper is to replace each three-dof spring-mass system by a set of equivalent springs, so that the free vibration characteristics of a rectangular plate carrying any number of three-dof spring-mass systems can be obtained from those of the same plate supported by the same number of sets of equivalent springs. Since the three dof's of the lumped mass for each three-dof spring-mass system are eliminated to yield a set of equivalent springs, the total dof of the entire vibrating system is not affected by the total number of the spring-mass systems attached to the rectangular plate. However, this is not true in the conventional finite element method (FEM), where the total dof of the entire vibrating system increases three if one more three-dof spring-mass system is attached to the rectangular plate. Hence, the computer storage memory required by using the presented equivalent spring method (ESM) is less than that required by the conventional FEM, and the more the total number of the three-dof spring-mass systems attached to the plate, the more the advantage of the ESM. In addition, since manufacturing a spring with the specified stiffness is much easier than making a three-dof spring-mass system with the specified spring constants and mass magnitude, the presented theory of replacing a three-dof spring-mass system by a set of equivalent springs will be also significant from this viewpoint.

• KIEE International Transactions on Power Engineering
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• 제4A권4호
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• pp.171-177
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• 2004

In the current age of the information oriented society in which we live, many people use PCs and are dependant on the databases provided by the network server. However, online data can be missed during the occurrence of a blackout and furthermore, power failure can greatly effect Power Quality. This has resulted in the trend of using interruption-free live-line work when trouble occurs in a power system. However, 83% of the population receives an electric shock experience when a laborer is performing interruption-free live-line work. In the interruption-free method, education and training problems have been pinpointed. However, there are few instructors to implement the necessary training. Furthermore, the trainees undergo only a short training period of just 4 weeks. In this paper, to develop a method with no restrictions on time and place and to ensure a reduction in the misuse of materials, immersion type virtual reality (or environment) technology is used. The users of a 3D immersion type VR training system can interact with the system by performing the equivalent action in a safe environment. Thus, it can be valuable to apply this training system to such dangerous work as 'Interruption-free live-line work exchanging COS (Cut-Out-Switch)'. In this program, the user carries out work according to instructions displayed through the window and speaker and cannot perform other tasks until each part of the task is completed in the proper sequence. The workers using this system can utilize their hands and viewpoint movement since they are in a real environment but the trainee cannot use all parts and senses of a real body with the current VR technology. Despite these weak points, when we consider the trends of improvement in electrical devices and communication technology, we can say that 3D graphic VR application has high potentiality.

• Journal of Periodontal and Implant Science
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• 제53권1호
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• pp.85-95
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• 2023

Purpose: In recent years, guided implant surgery has been widely used for the convenience of patients and surgeons. Further streamlining the surgical procedure would make implant surgery more convenient. Low-speed water-free conditions are often used in guided implant surgery. Therefore, in this study, we attempted to confirm once again whether drilling was safe at a low speed without water. The main purpose of this study was to evaluate whether a simplified drilling protocol that omits some intermediate steps in the drilling process was safe from the viewpoint of heat generation. Methods: D1 density artificial bone blocks were drilled under 50 rpm, 10 N·cm water-free conditions, and the surface temperature was measured using a digital infrared camera. First, drilling was performed with the sequential drilling method, which is the most widely used technique. Second, for each drill diameter, the temperature change was measured while performing simplified drilling with omission of the previous 1, 2, or 3 steps. Results: In sequential drilling, the heat generated during drilling at all diameters was less than the critical temperature of osteonecrosis (47℃) except for the ⌀2 drill. Statistical significance was observed in all groups when comparing sequential and simplified drilling in the ⌀3.2, ⌀3.8, and ⌀4.3 drills (P<0.001). However, in the simplified drilling procedures, the temperature was below the osteonecrosis threshold temperature (47℃) except for the ⌀4.3 drill with the omission of the previous 3 steps (⌀3.0, ⌀3.2, and ⌀3.8). Conclusions: In general, drilling under low-speed, water-free conditions has shown stable results in terms of heat generation. Simplified drilling showed statistically significantly greater heat generation than sequential drilling. However, most of the diameters and omitted steps seem to be clinically acceptable, so it will be useful if an appropriate selection is made according to the patient's clinical condition.

• 조형예술학연구
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• 제9권
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• pp.25-47
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• 2006

예술의 이해에 가장 본질적인 태도를 제시했던 이들 가운데 예술학의 제창자인 데스와(Max Dessoir)는 일찍이 "예술이라는 위대한 사실이 함의하는 것들을 모든 방향에서 정당하게 다루어야 할 필요가 있다"고 하면서, 예술이 "인간의 인식활동과 의지활동" 모두에서 기여하기를 희망하였다. 그의 이와 같은 진술에 의거해 보자면, 예술을 사회 역사적으로 해석하되 그것이 인식론적으로 그리고 존재론적으로 타당성을 지닌 것이어야 한다는 것이다. 이러한 정위하여 두 관점이 공존하면서 사회 역사적 해석의 방법을 모색하는데 이 글의 목적이 있다. 이와 같은 목적으로부터 이해의 문제를 주된 연구 범위로 하는 해석학에 대한 고찰은 당연한 절차가 되는데, 이는 해석학이 고대 신탁에 대한 해명으로부터 성서 해석 및 현대의 복잡하고 다의적인 텍스트로서의 예술에 이르기까지 그 본직적인 의미뿐 아니라 존재의 이해를 시도하는 것을 본연의 과제로 삼는 까닭이다. 해석은 그것의 규준을 발견하려는 방법적인 기술학(記述學)을 발전시켜 왔으나, 현대적인 의미에서 해석학은 그러한 방법적 발전보다는 인간 존재의 이해로 전환되어 가고 있다. 이에 대해 리쾨르(Paul Ricoeur)는 해석학이 '인식론'에서 '존재론'으로의 이해했다고 주장하였다. 그러나 해석 대상과 저자의 의도에 보다 충실해온 인식론적 관점과 해석 대상과 해석 주체와의 지평 융합에 의한 존재론적 관점은 우열을 가릴 수 없는 것임에도 불구하고, 두 관점은 각각 독립적인 성격만을 부각되어 배타적인 관계로 간주되어왔다. 이로부터 이 글은 두 관점의 상격만이 부각되어 배타적인 관계로 간주되어 왔다. 이로부터 이 글은 두 관점의 상호 의존적인 관계를 조명함으로써 이것에 의해 해석이 보다 충실해질 수 있음을 주장한다. 이와 같은 의도로부터 두 관점 모두를 상호 의존적인 해석의 절차로 수용하려는 방법적인 개념으로, '귀속'과 '순환'을 제기하였다. 이 두 개념은 해석의 과정에서 그 대상과 그로부터 발생하는 인간 이해의 문제를 밝히는데 상호 의존적이고 상호 보완적으로 작용하여 사회 역사적 해석에 도달하게 하는 구체적 전략이 되기 때문이다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.411-418
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• 1992

Recently, onset of bacterial disease, especially infiltration of chronic respiratory diseases have been increasing at high rate. The main cause of these diseases are originated from inappropriate sanitary management and slow progress in introducing system and herd free system, which are the base of productivity improvement in bigger pig management, Methods for the prevention and removal of these diseases, are divided into four categories. The first category includes prevention and removal of infectious diseases by organizing strict animal quarantine, enforcing vaccination, and legal regulation and disposal at the time of outbreak. The second category includes improvement of production systems. This purpose can be achieved by discontinuing the open herd system, which brings on the invasion of foreign pathogens and replacing the system by the closed type of farm. To Continue eradication process step-wisely by performing the all-in all-out system at every pig pen or herd level is also effective for this purpose. The third category includes introduction of herd free system can be achieved by repopulating conventional pigs with SPF pigs. If these means are unrealizable from economic or technical viewpoint, medicated early weaning system is perfomed. This system consists of disinfection of pigsty at pre-postpartum stage, application of drugs to pregnant sows and newborn piglets in accordance with the medication program, and early weaning and rearing of newborn piglets in isolation. The fourth category is sanital leading by veterinarians, aimed to eliminating incentives for diseases through diagnoses. Their main activities include periodical monitoring and improvement leading on each responsible subject.

• 천문학회보
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• 제41권1호
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• pp.46.1-46.1
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• 2016

The formation process of a current sheet is important for solar flare from a viewpoint of a space weather prediction. We therefore derive the temporal development of the spatial and statistical distribution of electric current density distributed in a flare-producing active region to describe the formation of a current sheet. We derive time sequence distribution of electric current density by applying a nonlinear force-free approximation reconstruction to Active Region 12158 that produces an X1.6-class flare. The time sequence maps of photospheric vector magnetic field used for reconstruction are captured by a Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamic Observatory (SDO) on 10th September, 2014. The spatial distribution of electric current density in NLFFF model well reproduce observed sigmoidal structure at the preflare phase, although a layer of high current density shrinks at the postflare phase. A double power-law profile of electric current density is found in statistical analysis. This may be expected to use an indicator of the occurrence of a solar flare.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 추계학술대회
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• pp.471-473
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• 2009

본 논문에서는 핸즈프리 전화통신을 위한 동시통화(double-talk) 및 잡음에 강건한 반향제거 시스템을 제안한다. 제안하는 반향제거 시스템은 동시통화 상황을 판별하기 위해 마이크 입력신호와 추정한 마이크 입력신호의 분산을 기반으로한 동시통화 검출 알고리즘을 사용하고 반향 경로 추정을 위한 적응 필터는 잔여반향 오차 전력과 AP 알고리즘의 투영차수를 곱하여 입력 신호의 자기공분산 행렬에 더해 정규화시킨 알고리즘을 적용한다. 컴퓨터 시뮬레이션을 통한 동시통화 및 주변 잡음이 큰 핸즈프리 환경에서 제안하는 방법이 AIC(acoustic interference cancellation) 측면에서 우수함을 보인다.

• 대한지리학회지
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• 제28권2호
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• pp.77-98
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• 1993

본 연구는 암설사면지형이 잘 발달하고 다양하게 분포하는 태백산맥의 남부산지를 대상으로 항공 사진판독과 도상계측 및 현지조사를 통하여 노출암설사면의 분포, 형태 및 퇴적물의 특성을 분석하고 사면의 지형적 배열과 지형발달에 관해서 연구한 논문으로써 분포적 특성에 있어서는 애추의 경우 기반암이 경암이거나 절리가 잘 발달된 지질에서, 암괴류의 경우는 화강섬록암 지질에서 높은 분포밀도를 보였다. 형태적 특성은 애추, 암괴류 모두 설상이 각각 83${\%}$, 80${\%}로 가장 많았으며 지형면의 경사도에 있어서는 애추가, 길이에 있어서는 암괴류가 각각 우세했다. 퇴적물의 특성중 암설의 평균입경은 암괴류가 보다 크게 나타났다. 한 지형면에서 암설의 장축방향성의 경우 방향성 있는 경우와 없는 경우가 있는데, 후자는 지형면상의 함몰로 그 방향성이 상실된 것으로 보인다. 끝으로 지형발달의 경우, 애추는 암석낙하(rock fall)에 의한 형성기(최종빙기)와 2차적인 영역에 의한 조정기(후빙기)로 암괴류는 암괴의 생성기(제3가 또는 제 4기의 간빙기), 암괴류의 형성기(최종빙기), 조정기(후빙기)로 구분할 수 있었다. 그리고 산지 사면의 배열유형은 6가지 유형으로 분류되었다.