• Title/Summary/Keyword: three-dimensions

Search Result 1,907, Processing Time 0.026 seconds

A Study on Sizing System of Cycling Wear Top for Athlete depending on Upper Body Type for High School Male Cyclists (고등학교 남자 사이클 선수의 상반신 유형 분류에 따른 선수용 사이클 웨어 상의 치수체계에 관한 연구)

  • Park, Hyunjeong;Do, Wolhee
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.44 no.6
    • /
    • pp.1139-1153
    • /
    • 2020
  • Upper body types were classified to develop the sizing system of the cycling wear top for the high school male cyclist. The research methods were performed using the anthropometric measurements of 111 high school male cyclists that included cluster analysis was performed. The research results are as follows. Type 1 (23.4%) has the longest biocromion length, is the tallest of the three types and a proper body type. Type 2 (25.2%) has the largest weight and developed muscles in the chest parts. Type 3 (51.4%) is the shortest of the three types and is a skinny body with a bending back. In order to develop a sizing system, the 12 anthropometric measurements were selected for correlation analysis. The bust circumference and stature were presented as the control dimensions of sizing system. The waist front, waist back length and biacromion length were less correlated with other items; consequently, they were independent items and were set as referable dimensions. Therefore, it was proposed as a sizing system because the 5 cm of bust and 5 cm of stature have a high coverage by body type. The total coverage rate was 81.9%.

Experimental and numerical investigation on the thickness effect of concrete specimens in a new tensile testing apparatus

  • Lei Zhou;Hadi Haeri;Vahab Sarfarazi;Mohammad Fatehi Marji;A.A. Naderi;Mohammadreza Hassannezhad Vayani
    • Computers and Concrete
    • /
    • v.31 no.1
    • /
    • pp.71-84
    • /
    • 2023
  • In this paper, the effects of the thickness of cubic samples on the tensile strength of concrete blocks were studied using experimental tests in the laboratory and numerical simulation by the particle flow code in three dimensions (PFC3D). Firstly, the physical concrete blocks with dimensions of 150 mm×190 mm (width×height) were prepared. Then, three specimens for each of seven different samples with various thicknesses were built in the laboratory. Simultaneously with the experimental tests, their numerical simulations were performed with PFC3D models. The widths, heights, and thicknesses of the numerical models were the same as those of the experimental samples. These samples were tested with a new tensile testing apparatus. The loading rate was kept at 1 kg/sec during the testing operation. Based on these analyses, it is concluded that when the thickness was less than 5 cm, the tensile strength decreased by increasing the sample thickness. On the other hand, the tensile strength was nearly constant when the sample thickness was raised to more than 5 cm (which can be regarded as a threshold limit for the specimens' thickness). The numerical outputs were similar to the experimental results, demonstrating the validity of the present analyses.

Design of Dynamically Focus-switchable Fresnel Zone Plates Based on Plasmonic Phase-change VO2 Metafilm Absorbers

  • Kyuho Kim;Changhyun Kim;Sun-Je Kim;Byoungho Lee
    • Current Optics and Photonics
    • /
    • v.7 no.3
    • /
    • pp.254-262
    • /
    • 2023
  • Novel thermo-optically focus-switchable Fresnel zone plates based on phase-change metafilms are designed and analyzed at a visible wavelength (660 nm). By virtue of the large thermo-optic response of vanadium dioxide (VO2) thin film, a phase-change material, four different plasmonic phase-change absorbers are numerically designed as actively tunable Gires-Tournois Al-VO2 metafilms in two and three dimensions. The designed phase-change metafilm unit cells are used as the building blocks of actively focus-switchable Fresnel zone plates with strong focus switching contrast (40%, 83%) and high numerical apertures (1.52, 1.70). The Fresnel zone plates designed in two and three dimensions work as cylindrical and spherical lenses in reflection type, respectively. The coupling between the thermo-optic effect of VO2 and localized plasmonic resonances in the Al nanostructures offer a large degree of freedom in design and high-contrast focus-switching performance based on largely tunable absorption resonances. The proposed method may have great potential in photothermal and electrothermal active optical devices for nonlinear optics, microscopy, 3D scanning, optical trapping, and holographic displays over a wide spectral range including the visible and infrared regimes.

Basic Human Needs in the Elderly Receiving Palliative Care: A Scoping Review

  • Thaciane Alves, Mota;Manuela Bastos, Alves;Ailton de Oliveira, Dantas;Erica Brandao, de Moraes;Anderson Reis, de Sousa;Rudval Souza, da Silva
    • Journal of Hospice and Palliative Care
    • /
    • v.25 no.4
    • /
    • pp.178-192
    • /
    • 2022
  • Purpose: This scoping review identified scientific evidence on basic human needs (BHNs) in the elderly receiving palliative care. Methods: Systematic searches were conducted using six electronic databases (PubMed, CINAHL, Scopus, Lilacs, IBECS, and Web of Science). The initial search resulted in 1,227 articles, of which 104 were identified as potentially relevant. Fifty-three articles that met the inclusion criteria were identified and included in the final analysis. Results: Using the three hierarchical dimensions of the BHN model, 17 needs were organised, with five in the psychobiological dimension, 10 in the psychosocial dimension, and two in the psychospiritual dimension. These needs reflect the importance of care with dignity and relief from suffering for the elderly in palliative care. Conclusion: Recognising impaired BHNs in elderly people receiving palliative care will contribute to better care plans for the elderly, considering the multiple bio-psycho-social-spiritual dimensions of BHNs. This review points to a predominance of psychosocial needs.

A Study on the Perception of Airline Non-Face-to-Face Boarding Service among Chinese Travelers (중국 여행객의 항공사 비대면 탑승수속 서비스에 대한 인식 연구)

  • Xin Shu Jiang;Young Woo Lee
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.32 no.2
    • /
    • pp.124-134
    • /
    • 2024
  • This study is based on the Expectation Confirmation Theory (ECT) and categorizes trust types in non-face-to-face boarding services into three dimensions: structural assurance, platform, and service provider. It analyzes the impact of these trust types on users' perceived usefulness, satisfaction, and continuous usage intentions. Using a structural equation model, the study found that the three dimensions of trust positively influence users' satisfaction and perception of usefulness, thereby promoting intentions for continuous use. However, perceived risk weakens the positive relationship between trust and continuous usage intentions. By exploring the moderating role of perceived risk in non-face-to-face boarding services, this study analyzes its impact on user behavior patterns, contributing to the optimization of service design and enhancement of user trust. This study promotes widespread acceptance and continuous use of the service, and is crucial for developing effective non-contact service strategies that meet the needs and expectations of Chinese travelers in the post-pandemic travel environment. The findings provide a new perspective and empirical evidence for understanding user attitudes and behaviors towards non-face-to-face services, holding significant theoretical and practical implications.

The Distinct Impact Dimensions of the Prestige Indices in Author Citation Networks (저자 인용 네트워크에서 명망성 지표의 차별된 영향력 측정기준에 관한 연구)

  • Ahn, Hyerim;Park, Ji-Hong
    • Journal of the Korean Society for information Management
    • /
    • v.33 no.2
    • /
    • pp.61-76
    • /
    • 2016
  • This study aims at proposing three prestige indices-closeness prestige, input domain, and proximity prestige- as useful measures for the impact of a particular node in citation networks. It compares these prestige indices with other impact indices as it is still unknown what dimensions of impact these indices actually measure. The prestige indices enable us to distinguish the most prominent actors in a directed network, similar to the centrality indices in undirected networks. Correlation analysis and principal component analysis were conducted on the author citation network to identify the differentiated implications of the three prestige indices from the existing impact indices. We selected simple citation counting, h-index, PageRank, and the three kinds of centrality indices which assume undirected networks as the existing impact measures for comparison with the three prestige indices. The results indicate that these prestige indices demonstrate distinct impact dimension from the other impact indices. The prestige indices reflect indirect impact while the others direct impact.

New classification of lingual arch form in normal occlusion using three dimensional virtual models

  • Park, Kyung Hee;Bayome, Mohamed;Park, Jae Hyun;Lee, Jeong Woo;Baek, Seung-Hak;Kook, Yoon-Ah
    • The korean journal of orthodontics
    • /
    • v.45 no.2
    • /
    • pp.74-81
    • /
    • 2015
  • Objective: The purposes of this study were 1) to classify lingual dental arch form types based on the lingual bracket points and 2) to provide a new lingual arch form template based on this classification for clinical application through the analysis of three-dimensional virtual models of normal occlusion sample. Methods: Maxillary and mandibular casts of 115 young adults with normal occlusion were scanned in their occluded positions and lingual bracket points were digitized on the virtual models by using Rapidform 2006 software. Sixty-eight cases (dataset 1) were used in K-means cluster analysis to classify arch forms with intercanine, interpremolar and intermolar widths and width/depth ratios as determinants. The best-fit curves of the mean arch forms were generated. The remaining cases (dataset 2) were mapped into the obtained clusters and a multivariate test was performed to assess the differences between the clusters. Results: Four-cluster classification demonstrated maximum inter-cluster distance. Wide, narrow, tapering, and ovoid types were described according to the intercanine and intermolar widths and their best-fit curves were depicted. No significant differences in arch depths existed among the clusters. Strong to moderate correlations were found between maxillary and mandibular arch widths. Conclusions: Lingual arch forms have been classified into 4 types based on their anterior and posterior dimensions. A template of the 4 arch forms has been depicted. Three-dimensional analysis of the lingual bracket points provides more accurate identification of arch form and, consequently, archwire selection.

Three dimensional seismic and static stability of rock slopes

  • Yang, X.L.;Pan, Q.J.
    • Geomechanics and Engineering
    • /
    • v.8 no.1
    • /
    • pp.97-111
    • /
    • 2015
  • The kinematical approach of limit analysis is used to estimate the three dimensional stability analysis of rock slopes with nonlinear Hoek-Brown criterion under earthquake forces. The generalized tangential technique is introduced, which makes limit analysis apply to rock slope problem possible. This technique formulates the three dimensional stability problem as a classical nonlinear programming problem. A nonlinear programming algorithm is coded to search for the least upper bound solution. To prove the validity of the present approach, static stability factors are compared with the previous solutions, using a linear failure criterion. Three dimensional seismic and static stability factors are calculated for rock slopes. Numerical results of indicate that the factors increase with the ratio of slope width and height, and are presented for practical use in rock engineering.

Education and Application of Modeling on 3D Structure using Geogebra (지오지브라를 이용한 3차원 구조물의 모델링 교육과 응용)

  • Chung, Tae-Eun;Kim, Tae-Hwan
    • Korean Journal of Computational Design and Engineering
    • /
    • v.20 no.2
    • /
    • pp.93-103
    • /
    • 2015
  • In this study, we organize and explain various ways to construct 3D models in the 2D plane using Geogebra, mathematical education software that enables us to visualize dynamically the interaction between algebra and geometry. In these ways, we construct three unit vectors for 3 dimensions at a point on the Cartesian coordinates, on the basis of which we can build up the 3D models by putting together basic mathematical objects like points, lines or planes. We can apply the ways of constructing the 3 dimensions on the Cartesian coordinates to modeling of various structures in the real world, and have chances to translate, rotate, zoom, and even animate the structures by means of slider, one of the very important functions in Geogebra features. This study suggests that the visualizing and dynamic features of Geogebra help for sure to make understood and maximize learning effectiveness on mechanical modeling or the 3D CAD.

Analytic springback prediction in cylindrical tube bending for helical tube steam generator

  • Ahn, Kwanghyun;Lee, Kang-Heon;Lee, Jae-Seon;Won, Chanhee;Yoon, Jonghun
    • Nuclear Engineering and Technology
    • /
    • v.52 no.9
    • /
    • pp.2100-2106
    • /
    • 2020
  • This paper newly proposes an efficient analytic springback prediction method to predict the final dimensions of bent cylindrical tubes for a helical tube steam generator in a small modular reactor. Three-dimensional bending procedure is treated as a two-dimensional in-plane bending procedure by integrating the Euler beam theory. To enhance the accuracy of the springback prediction, mathematical representations of flow stress and elastic modulus for unloading are systematically integrated into the analytic prediction model. This technique not only precisely predicts the final dimensions of the bent helical tube after a springback, but also effectively predicts the various target radii. Numerical validations were performed for five different radii of helical tube bending by comparing the final radius after a springback.