• 한국해양공학회지
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• 제26권4호
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• pp.57-63
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• 2012

In this paper, a Bayesian classifier based on PCA (principle component analysis) is proposed to classify underwater transient signals using $16^{th}$ order LPC (linear predictive coding) coefficients as feature vector. The proposed classifier is composed of two steps. The mechanical signals were separated from biological signals in the first step, and then each type of the mechanical signal was recognized in the second step. Three biological transient signals and two mechanical signals were used to conduct experiments. The classification ratios for the feature vectors of biological signals and mechanical signals were 94.75% and 97.23%, respectively, when all 16 order LPC vector were used. In order to determine the effect of underwater noise on the classification performance, underwater ambient noise was added to the test signals and the classification ratio according to SNR (signal-to-noise ratio) was compared by changing dimension of feature vector using PCA. The classification ratios of the biological and mechanical signals under ocean ambient noise at 10dB SNR, were 0.51% and 100% respectively. However, the ratios were changed to 53.07% and 83.14% when the dimension of feature vector was converted to three by applying PCA. For correct, classification, it is required SNR over 10 dB for three dimension feature vector and over 30dB SNR for seven dimension feature vector under ocean ambient noise environment.

• 자연과학논문집
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• 제4권
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• pp.191-220
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• 1991

Human Visual System(HVS)의 특성과 image의 textural regions의 roughness을 이용하여 image segmentation을 행하여 high compression에서도 고화질을 나타내는 새로운 image coder를 이 논문에서 논한다. 제안된 image coder는 constant segments를 가진 segmentation-based image coding technique의 문제들을 다음과 같은 방법론을 제안함으로써 해결하였다. Image를 HVS으로 보았을 때 degree of roughness에 관하여 textually homogeneous regions으로 segmentation하였다. Fractal dimension을 roughness of textural regions을 측정하기 위하여 사용하였다. Segmentation은 fractal dimension을 thresholding하여 textural regions이 three texture classes로 분류하였다(perceived constant intensity, smooth texture, and rough texture). High compression을 가지는 고질화의 image coder는 각각의 segment boundary와 각각의 texture class에 효율적인 coding technique를 적용 함으로 얻었다.

• 한국실내디자인학회논문집
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• 제19권5호
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• pp.56-66
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• 2010

This study proposes a thesis of architectural concepts and visual dimension systems, and the comparison between steps of spatial formation and dimensional alteration. The second chapter, to form the basis of this study, explains the dimensional alterations and changes of fundamental notion of space. In the third chapter, history of space, architectural formations, and changes of the viewpoint are analyzed as objects of study. The forth chapter presents the interrelation between dimensional alteration and the transition in fundamental notion of space, demonstrating that modern architecture has been born from these cultural movements. Lastly, the fifth chapter suggests possibilities on further studies and the following conclusions: First, architectural spaces have been changed, in accordance with the changes of culture, art and the tools that regulate architectural design. Proportional regulations by two-dimensional tools and depth through three-dimensional drawings are created. Second, architectural spaces gained depth by recognizing movement and time that have induced formations to change, creating various aesthetic backgrounds and attempts. Third, the aesthetic background and cosmologic spatial concept have led the visualization and changes of architectural experience. It created the design tools and shapes originated in dynamism and vitality. Forth, diversification of fundamental spatial concepts has become palimpsest and complex, and been divided into four dimensions; expressional two-dimensional space, perspective three-dimensional space, forth-dimensional space of time and experience, and imagery space formed by body movement. Fifth, architecture has been influenced by the elevated viewpoint that understands the whole world as a space. It has evolved from the two-dimensional proportion principle, change of depth and vanishing point to multidimensional space of movement and time. Sixth, changes of fundamental notion of space have arisen from changes of visual dimensions in times. In other words, space has been developed from two-dimensional space to multidimensional space by accepting visual dimension, grasping distance, direction, depth, height, velocity, movement, gravity, power and structure.

• 성인간호학회지
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• 제19권1호
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• pp.155-165
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• 2007

Purpose: The purpose of this study was to determine the relationships of pain cognition, performance status, and hope with health-related quality of life. Methods: Patients(n=149) with various cancer diagnoses completed the SF-36 standard Korean Version and the Herth Hope Index. The Perceived Meanings of Cancer Pain Inventory was used to measure the cognition dimension of pain, whereas the Brief Pain Inventory Korean version was used to represent the sensory dimension of pain. Results: The patients in the pain group had significant differences in the three dimensions(loss, threat, spiritual awareness) of pain cognition. There were statistically significant negative correlations between the three dimensions(loss, threat, and spiritual awareness) of pain cognitions and SF-36 dimension, and the positive correlations between challenge dimension and SF-36 dimension. Hope had the positive correlation with SF-36 dimensions. Conclusion: Pain has a negative impact on health-related quality of life, especially on physical health. However, patients who ascribed more positive meaning to their pain, tended to have a higher quality of life. Therefore, nursing intervention to reinforce the positive aspects of pain cognition is to empower patients to create a sense of control and assume an active role in pain management and quality of life.

• 대한치과교정학회지
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• 제45권2호
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• pp.59-65
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• 2015

Objective: To investigate skeletal and dental changes after application of a mandibular setback surgery-first orthodontic treatment approach in cases of skeletal Class III malocclusion. Methods: A retrospective study of 34 patients (23 men, 11 women; mean age, $26.2{\pm}6.6years$) with skeletal Class III deformities, who underwent surgery-first orthodontic treatment, was conducted. Skeletal landmarks in the maxilla and mandible at three time points, pre-treatment (T0), immediate-postoperative (T1), and post-treatment (T2), were analyzed using cone-beam computed tomography (CBCT)-generated half-cephalograms. Results: The significant T0 to T1 mandibular changes occurred $-9.24{\pm}3.97mm$ horizontally. From T1 to T2, the mandible tended to move forward $1.22{\pm}2.02mm$, while the condylar position (Cd to Po-perpendicular plane) shifted backward, and the coronoid process (Cp to FH plane) moved vertically. Between T1 and T2, the vertical dimension changed significantly (p < 0.05). Changes in the vertical dimension were significantly correlated to T1 to T2 changes in the Cd to Po-perpendicular plane (r = -0.671, p = 0.034), and in the Cp to FH plane (r = 0.733, p = 0.016), as well as to T0 to T1 changes in the Cp to Po-perpendicular plane (r = 0.758, p = 0.011). Conclusions: Greater alterations in the vertical dimension caused larger post-treatment (T2) stage skeletal changes. Studying the mandibular position in relation to the post-surgical vertical dimension emphasized the integral importance of vertical dimension control and proximal segment management to the success of surgery-first orthodontic treatment.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 추계학술발표회 논문집
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• pp.219-224
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• 2003

Recently, the number of the use of Digital Photogrammetry is increasing, the Digital Photogrammetry is used for the acquisition of images, remote sensing and three dimension location. Especially, the three dimension location is more activated to use digital camera for the Digital Photogrammetry. The reason is that it is cheap and easy to use and also it has high confidence. Using non-metric digital camera not metric camera, in this research, to get images and apply the images to the Direct Liner Transformation which is one of the techniques in Digital Photogrammetry to get three dimensional location of a point. Ⅰ programmed the procedure with Visual C++ to get the position of points speedly and I tested possibility whether it can analyze the displacement and the existence of structure with measurement system which is structured by a inexpensive non-metric digital camera.

• 소성∙가공
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• 제17권3호
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• pp.155-160
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• 2008

We analyzed a sequence of multi-stage automatic cold forging processes composed of four axisymmetric processes followed by a non-axisymmetric process using rigid-plastic finite element based forging simulators. The forging sequence selected for an example involves a piercing process and a heading process accompanying folding or overlapping, which all make it difficult to simulate the processes. To reduce computational time and to enhance the solution reliability, only the non-symmetric process was analyzed by the three-dimensional approach after the axisymmetric processes were analyzed by the two-dimensional approach. It has been emphsized that this capability is very helpful in simulating the multi-stage automatic forging processes which are next to axisymmetric or involve several axisymmetric processes.

• 한국수자원학회논문집
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• 제31권5호
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• pp.587-597
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• 1998

기존의 연구자들은 하천길이의 프랙탈 차원은 유역내 전체 하천에 대해 균일하며 그 수치도 1.09~1.13로 상당히 크게 보았다. 그렇지만 국제수문개발계획의 대표유역중 하나인 평창강수계내 이목정 소유역을 대상으로 1/50,000, 1/25,000, 1/5,000의 3개 축척 지형도를 이용하여 프랙탈 차원을 산정한 결과 하천차수별로 서로 다른 프랙탈 차원을 갖는 것을 발견하였고, 또한 전체 하천으로 보아도 기존 연구자들이 제안한 수치보다 작은 수치를 보였다. 이목적 소유역내 하천의 프랙탈 차원을 산정한 결과에 의하면 기존의 국내외의 연구가 전체 하천을 균일한 프랙탈 차원을 갖는 것으로 보는 것과 달리 1차, 2차 하천은 1.033, 이보다 하천차주가 높은 3차, 4차 하천을 1.014의 값을 보이는 등 하천차수별로 프랙탈 차원이 다르게 산정되었다. 또한 전체적인 하천길이에 대한 프랙탈 차원도 1.027로서 국내외에서 제시된 기존의 하천길이에 대한 프랙탈 차원인 1.09~1.13 사이의 수치는 실제보다 너무 과대평가된 것으로 추정된다.

• 대한수학회논문집
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• 제13권3호
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• pp.561-577
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• 1998

We study (n＋3)-dimensional contact three CR submanifolds of a Riemannian manifold with Sasakian three structure and investigate some characterizations of $S^{4r＋3}$(a) $\times$ $S^{4s＋3}$(b) ($a^2$＋ $b^2$=1, 4(r ＋ s) = n - 3) as a contact three CR sub manifold of a (4m＋3)-dimensional unit sphere.

• 한국경제지리학회지
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• 제5권2호
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• pp.157-174
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• 2002

본 연구는 일반인들이 농촌 어메니티 인식의 구조와 의미를 고찰하였다. 어메니티 관련 요소들에 대한 중요도 평가를 측정한 설문결과를 바탕으로 요인분석에 의해 중요한 인식의 차원을 도출하고 상이한 조사집단간 비교를 실시하였다. 분석 결과, 일반인들의 농촌어메니티 인식에 있어서 생활여건의 편리성, 자연친화성, 역사문화성 등의 세 가지 핵심적 차원들이 존재하는 것으로 확인되었다. 그러나 기대와 달리 도시민이나 농촌주민들 모두 이 세 가지 핵심차원들간의 상대적 중요성을 동일한 양상으로 평가하고 있는 것으로 분석되었다. 상대적으로 편리한 생활여건을 갖춘 도시민들조차 생활여건의 편리함을 희생하면서까지 농촌어메니티를 추구하지는 않는 것으로 판단된다. 따라서 역사문화성, 자연친화성에 더 강조하는 학계나 계획가들의 태도와는 일정한 괴리가 존재하고 있는 것으로 밝혀졌다.