• 한국해양공학회지
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• 제23권4호
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• pp.32-37
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• 2009

An analytic similarity shape solution was studied for a two-dimensional floating and fluid-filled membrane structure. The static shape of a membrane structure can be expressed as a set of nonlinear ordinary differential equations. The integration of curvature leads to an analytic solution for the shape, which contains unknown boundary values. Matching the upper and lower shapes at the free surface incorporated with their buoyancy allowed the unknowns to be determined. Some characteristic values of similarity shapes were evaluated and shapes are illustrated for various density ratios and volume efficiency ratios.

• 한국CDE학회논문집
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• 제9권1호
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• pp.51-61
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• 2004

Mechanical parts are often grouped into part families based on the similarity of their shapes, to support efficient manufacturing process planning and design modification. The 2-part sequence papers present similarity assessment techniques to support part family classification for machined parts. These exploit the multiple feature decompositions obtained by the feature recognition method using convex decomposition. Convex decomposition provides a hierarchical volumetric representation of a part, organized in an outside-in hierarchy. It provides local accessibility directions, which supports abstract and qualitative similarity assessment. It is converted to a Form Feature Decomposition (FFD), which represents a part using form features intrinsic to the shape of the part. This supports abstract and qualitative similarity assessment using positive feature volumes.. FFD is converted to Negative Feature Decomposition (NFD), which represents a part as a base component and negative machining features. This supports a detailed, quantitative similarity assessment technique that measures the similarity between machined parts and associated machining processes implied by two parts' NFDs. Features of the NFD are organized into branch groups to capture the NFD hierarchy and feature interrelations. Branch groups of two parts' NFDs are matched to obtain pairs, and then features within each pair of branch groups are compared, exploiting feature type, size, machining direction, and other information relevant to machining processes. This paper, the second one of the two companion papers, describes the similarity assessment method using NFD.

• 한국CDE학회논문집
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• 제9권1호
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• pp.44-50
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• 2004

Mechanical parts are often grouped into part families based on the similarity of their shapes, to support efficient manufacturing process planning and design modification. The 2-part sequence papers present similarity assessment techniques to support part family classification for machined parts. These exploit the multiple feature decompositions obtained by the feature recognition method using convex decomposition. Convex decomposition provides a hierarchical volumetric representation of a part, organized in an outside-in hierarchy. It provides local accessibility directions, which supports abstract and qualitative similarity assessment. It is converted to a Form Feature Decomposition (FFD), which represents a part using form features intrinsic to the shape of the part. This supports abstract and qualitative similarity assessment using positive feature volumes. FFD is converted to Negative Feature Decomposition (NFD), which represents a part as a base component and negative machining features. This supports a detailed, quantitative similarity assessment technique that measures the similarity between machined parts and associated machining processes implied by two parts' NFDs. Features of the NFD are organized into branch groups to capture the NFD hierarchy and feature interrelations. Branch groups of two parts' NFDs are matched to obtain pairs, and then features within each pair of branch groups are compared, exploiting feature type, size, machining direction, and other information relevant to machining processes. This paper, the first one of the two companion papers, describes the similarity assessment methods using convex decomposition and FFD.

• 한국산업정보학회논문지
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• 제6권1호
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• pp.33-38
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• 2001

본 논문에서는 영상의 형태 특징을 이용한 영상 검색 시스템을 제안한다. 형태특징을 얻기 위해서 먼저 체인코드를 이용하여 경계선 추출을 추출하였다. 형태특징으로 객체의 경계선과 무게중심까지의 합, 표준편차 그리고 객체의 장축과 단축 비율 등을 추출하였다. 이러한 형태특징 정보를 이용하여 데이터 베이스에 저장된 영상과 질의 영상을 비교하여 유사도 순위에 따라 후보 영상들을 검색하였다. 본 실험의 결과 크기, 회전 이동 등의 변화에 둔감하였다. 약 170개의 폐곡선을 이루는 영상에 대한 검색 실험을 통하여 모양 정보에 대한 정확도를 측정하였다. 실험 결과 평균 Recall/Precision이 0.72/0.83를 보임으로써 제안된 방법이 유용함을 보였다.

• 한국CDE학회논문집
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• 제14권6호
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• pp.404-414
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• 2009

In the computational molecular analysis, 3D structural comparison for protein searching plays a very important role. As protein databases have been grown rapidly in size, exhaustive search methods cannot provide satisfactory performance. Because exhaustive search methods try to handle the structure of protein by using sphere set which is converted from atoms set, the similarity calculation about two sphere sets is very expensive. Instead, the filter-and-refine paradigm offers an efficient alternative to database search without compromising the accuracy of the answers. In recent, a very fast algorithm based on the inter-atomic distance has been suggested by Ballester and Richard. Since they adopted the moments of distribution with inter-atomic distance between atoms which are rotational invariant, they can eliminate the structure alignment and orientation fix process and perform the searching faster than previous methods. In this paper, we propose a new 3D shape descriptor. It has properties of the general shape distribution and useful property in screening the molecular database. We show some experimental results for the validity of our method.

• Design & Manufacturing
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• 제17권3호
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• pp.34-40
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• 2023

In this study, real-time collection of mold vibration signals during injection molding processes was achieved through IoT devices installed on the mold surface. To analyze changes in the collected vibration signals, injection molding was performed under six different process conditions. Analysis of the mold vibration signals according to process conditions revealed distinct trends and patterns. Based on this result, cosine similarity was applied to compare pattern changes in the mold vibration signals. The similarity in time and acceleration vector space between the collected data was analyzed. The results showed that under identical conditions for all six process settings, the cosine similarity remained around 0.92±0.07. However, when different process conditions were applied, the cosine similarity decreased to the range of 0.47±0.07. Based on these results, a cosine similarity threshold of 0.60~0.70 was established. When applied to the analysis of mold vibration signals, it was possible to determine whether the molding process was stable or whether variations had occurred due to changes in process conditions. This establishes the potential use of cosine similarity based on mold vibration signals in future applications for real-time monitoring of molding process changes and anomaly detection.

• 한국실내디자인학회논문집
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• 제19권6호
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• pp.20-29
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• 2010

Art historians and critics have defined the style as common features appeared in a class of objects. Abstract common features from a set of objects have been used as a bench mark for date and location of original works. Commonalities in shapes are identified by relationships as well as physical properties from shape descriptions. This paper will focus on how the computer and human can recognize common shape properties from a class of shape objects to learn design knowledge. Shape representation using schema theory has been explored and possible inductive generalization from shape descriptions has been investigated. Also learned shape knowledge can be used. for new design process as design concept. Several design process such as parametric design, replacement design, analogy design etc. are used for these design processes. Works of Mario Botta and Louis Kahn are analyzed for explicitly clarifying the process from conceptual ideas to final designs. In this paper, theories of computer science, artificial intelligence, cognitive science and linguistics are employed as important bases.

• 한국의류산업학회지
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• 제23권6호
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• pp.826-835
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• 2021

The purpose of this study was to compare the similarity between actual and virtual pants using a virtual 3D CLO program. A subject corresponding to the average size of a women in her twenties was selected and an avatar with the same specifications was produced. Silhouettes of the pants were classified into trousers, slacks, and wide pants and images of actual and virtual pants were evaluated from the front, side, and back. The results were as follows: Overall, the resemblance of the trousers was evaluated higher than that of other pants. The average similarity of trousers was 4.20 at the front, 3.98 at the side, and 4.17 at the back, which was much like the actual clothing. In contrast, that of the slacks was 3.62, 3.73, and 3.79 and of the wide pants was 3.81, 3.53, and 3.97. The similarity between the actual and virtual clothing was relatively well reproduced when the shape of the pants was like the silhouette of the human body. However, if the pants were tight or loose, virtual fits failed to display the wrinkles caused by the tightness or the excessive slack. The virtual fit showed fewer wrinkles and did not depict the location and the shape of hemlines as accurately as the actual fit, although virtual fits adequately displayed the baseline and dart on the pants.

• 복식
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• 제64권7호
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• pp.97-113
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• 2014

The study aims to determine the significance and characteristics of self-similarity inherent in natural objects or phenomena, the existence of self-similarity in design created by fashion designers, and the traits and internal significance implied in self-similarity and their effects on fashion. The subject of the study is Viktor & Rolf, and the scope of the study is the collections created from 2001 to 2014, which include designs implemented in their early years and those unveiled in the media. Self-similarity means attributes of a fractal structure appearing without change in the original form, even after modification of scale or direction in terms of shape or phenomena. As self-similarity is applied to the arts and design sectors, it leads people to pay attention to fundamental characteristics and intrinsic forms as a factor of expressing a unique creative world. Analysis of Viktor & Rolf collections generated ribbons, overlapping/juxtaposition, side decorations and exaggerated design elements as basic units of self-similarity. These factors had self-similarity rates as high as 84%. Self-similarity was established as design elements formed in the incipient stage were repeated in a certain form, and continued for a long period of time. It served as an element that recognizes design and a fashion designer at the same time. Characteristics of self-similarity appearing in Viktor & Rolf collections can be summarized as homeostasis based on an equivalent relationship, balance based on self-organization, reducibility into essential elements, and uniqueness based on odd shapes. These characteristics influenced the pursuit of consistent brand image, the maintenance of a fashion designer's creative world, the formation of styles and the expression of a fashion designer's identity.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2000년도 춘계학술대회논문집
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• pp.71-74
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• 2000

The equi-potential lines designed in the electric field are introduced to find the preform shape in axisymmetric hot forging. The equi-potential lines generated between two conductors of different voltages show similar trends of the minimum work paths between the undeformed shape and the deformed shape. Base on this similarity the equi-potential lines obtained by arrangement of the initial and final shapes are utilized for the design of preform and then the artificial neural network is used to find the range of initial volume and potential value of the electric field.