• Title/Summary/Keyword: Investigating Types

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A Study of the Shearing Force as a Function Trim Punch Shape and Shearing Angle (트리밍펀치 형상과 전단 각에 따른 전단하중 특성에 관한 연구)

  • Yoo, C.K.;Won, S.T.
    • Transactions of Materials Processing
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    • v.24 no.2
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    • pp.77-82
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    • 2015
  • By investigating the practical use of trim punch configurations for shearing of vehicle panels, the current study first reviews the shearing angle as part of the shearing die design. Based on this review, four different types of trim punch shapes (i.e., horizontal, slope, convex, and concave type) and shearing angles(i.e., 0.76°, 1.53°, 2.29°, 3.05°, 3.81°) were investigated. In order to conduct shearing experiments, four types of trim punch dies were made. The four trim punch dies were tested under various conditions. The experiments used the four trim punch shapes and the five shearing angles. The shearing force varied by shape and decreased from horizontal, slope, convex, to concave for the same shearing angle. The magnitude of shearing force showed differences between the convex and the concave shapes due to the influence of constrained shearing versus free shearing. The test results showed that compared to the horizontal trim punch shearing force, the decrease of the slope, convex, and concave shearing forces were 22.6% to 60.4%. Based on the results, a pad pressure of over 30% is suggested when designing a shearing die.

Damage Index of Steel Members under Severe Cyclic Loading

  • Park, Yeon-soo;Han, Suk-yeol;Suh, Byoung-chal;Jeon, Dong-ho;Park, Sun-joon
    • Computational Structural Engineering : An International Journal
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    • v.3 no.1
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    • pp.9-17
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    • 2003
  • This paper aims at investigating the damage process of steel members leading to the failure under strong repeated loading, proposing the damage index using various factors related to the damage, and developing the analysis method for evaluating the damage state. Cantilever-type steel members were analyzed under uniaxial load and combined with a constant axial load, considering a horizontal displacement history. In analyzing the models, loading patterns and steel types (SS400, SM570, Posten80) were considered as main parameters. From the analysis results, the effects of parameter on the failures mode, the deformation capacity, the damage process are also discussed. Each failure process was compared as steel types. Consequently, the failure of steel members under strong repeated loading was determined by loading. Especially it was seen that the state of the failure is closely related to the local strain.

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Alternatives to Enhance Flat Slab Ductility

  • Husain, Mohamed;Eisa, Ahmed S.;Roshdy, Ramy
    • International Journal of Concrete Structures and Materials
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    • v.11 no.1
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    • pp.161-169
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    • 2017
  • Flat slab systems are vastly used in multi-story buildings because of their savings in story height and construction time, as well as for their flexibility in architectural remodeling. However, they frequently suffer brittle punching-shear failure around columns, especially when subjected to lateral loads. Therefore, seismic codes labeled flat slabs as non-ductile systems. This research goal is investigating some construction alternatives to enhance flat slab ductility and deformability. The alternatives are: adding different types of punching-shear reinforcement, using discreet fibers in concrete mixes, and increasing thickness of slab around columns. The experimental study included preparation and testing of seven half-scale interior slab-column connections up to failure. The first specimen is considered a reference, the second two specimens made of concrete mixes with different volumetric ratios of polymer fibers. Another three specimens reinforced with different types of punching-shear reinforcement, and the last specimen constructed with drop panel of inverted pyramidal shape. It is found that using the inverted pyramid-shape drop panel of specimen, increases the punching-shear capacity, and the initial and the post-cracking stiffnesses. The initial elastic stiffnesses are different for all specimens especially for the slab with closed stirrups where it is experienced the highest initial stiffness compared to the reference slab.

Study about a public sign in Cheon - An station (천안역에 있어서 공공사인에 관한 연구)

  • Yoo, Hyun-Bae;Choi, Ji-Sook
    • Journal of Digital Contents Society
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    • v.8 no.4
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    • pp.475-481
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    • 2007
  • This study analyzes the sign system, the types and distribution of sign boards, around Cheon-An railway station which is a representative public space, and it gives a classification of the system through investigating them by types and location. Some points are issued on the kind of the system established, the location of the information, and the clustered plantation of them. Thus, it is required to differentiate sign systems in each section, to distribute them uniformly rather than aggregated densely, and to place them at pertinent locations with the analysis of people's behavior avoiding improvised decision. In conclusion, pedestrians' needs on them should be analyzed first no matter where the sign is installed so that it is possible to develop tranquil atmosphere for people to use through providing proper information.

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Comparison of the WSA-ENLIL CME propagation model with three cone types and an empirical model

  • Jang, Soojeong;Moon, Yong-Jae;Na, HyeonOck
    • The Bulletin of The Korean Astronomical Society
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    • v.37 no.2
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    • pp.124.1-124.1
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    • 2012
  • We have made a comparison of the WSA-ENLIL CME propagation model with three cone types and an empirical model using 29 halo CMEs from 2001 to 2002. These halo CMEs have cone model parameters from Michalek et al. (2007) as well as their associated interplanetary (IP) shocks. For this study we consider three different cone models (an asymmetric cone model, an ice-cream cone model and an elliptical cone model) to determine CME cone parameters (radial velocity, angular width and source location), which are used for input parameters of the WSA-ENLIL CME propagation model. The mean absolute error (MAE) of the arrival times at the Earth for the elliptical cone model is 10 hours, which is about 2 hours smaller than those of the other models. However, this value is still larger than that (8.7 hours) of an empirical model by Kim et al. (2007). We are investigating several possibilities on relatively large errors of the WSA-ENLIL cone model, which may be caused by CME-CME interaction, background solar wind speed, and/or CME density enhancement.

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A Study on the Clothing Buying Motive and Information Source according to Lifestyle Type of Women in Their 50's and 60's (50.60대 여성의 라이프스타일에 따른 의복구매동기와 정보원천에 관한 연구)

  • 한성지;김문숙
    • The Research Journal of the Costume Culture
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    • v.10 no.2
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    • pp.116-131
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    • 2002
  • The purposes of this study were to analyze the lifestyle of women in their 50's and 60's and to provide the basis for the efficient strategy of silver market by classifying women in their 50's and 60's according to lifestyle types and investigating the effect of consumers' lifestyle and demographic characteristics on consumers' clothing buying motived and information sources. In this study, a self-administered questionnaire was distributed to women in their 50's and 60's. 226 questionnaires of 350 were used in the following analysis. The data were analyzed with the SPSS package. The results of this study were as follows. First, lifestyle were analyzed to find out the underlying factors, and then the subjects were grouped according to factor scores by the cluster analysis. Four lifestyle types were defined. They were the traditional family-oriented, the ostentatious purchase, the economical material-oriented, the active economics-oriented type. Second, a consumer's buying motives and information sources in buying clothing were significantly different depending on the consumer's lifestyle. The ostentatious purchase type attached importance to impulse buying and in diversion in clothing buying motives and display in information sources. The economical material-oriented type tend to buy clothes to purchase economically during bargain sales. The active economics-oriented type attached importance to worn out clothing in buying motives.

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Investigation of blasting impact on limestone of varying quality using FEA

  • Dimitraki, Lamprini S.;Christaras, Basile G.;Arampelos, Nikolas D.
    • Geomechanics and Engineering
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    • v.25 no.2
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    • pp.111-121
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    • 2021
  • Large deformation and rapid pressure propagation take place inside the rock mass under the dynamic loads caused by the explosives, on quarry faces in order to extract aggregate material. The complexity of the science of rock blasting is due to a number of factors that affect the phenomenon. However, blasting engineering computations could be facilitated by innovative software algorithms in order to determine the results of the violent explosion, since field experiments are particularly difficult to be conducted. The present research focuses on the design of a Finite Element Analysis (FEA) code, for investigating in detail the behavior of limestone under the blasting effect of Ammonium Nitrate & Fuel Oil (ANFO). Specifically, the manuscript presents the FEA models and the relevant transient analysis results, simulating the blasting process for three types of limestone, ranging from poor to very good quality. The Finite Element code was developed by applying the Jones-Wilkins-Lee (JWL) equation of state to describe the thermodynamic state of ANFO and the pressure dependent Drucker-Prager failure criterion to define the limestone plasticity behavior, under blasting induced, high rate stress. A progressive damage model was also used in order to define the stiffness degradation and destruction of the material. This paper performs a comparative analysis and quantifies the phenomena regarding pressure, stress distribution and energy balance, for three types of limestone. The ultimate goal of this research is to provide an answer for a number of scientific questions, considering various phenomena taking place during the explosion event, using advanced computational tools.

Human Pluripotent Stem Cell-Derived Retinal Organoids: A Viable Platform for Investigating the Efficacy of Adeno-Associated Virus Gene Therapy

  • Hyeon-Jin Na;Jae-Eun Kwon;Seung-Hyun Kim;Jiwon Ahn;Ok-Seon Kwon;Kyung-Sook Chung
    • International Journal of Stem Cells
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    • v.17 no.2
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    • pp.204-211
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    • 2024
  • With recent advances in adeno-associated virus (AAV)-based gene therapy, efficacy and toxicity screening have become essential for developing gene therapeutic drugs for retinal diseases. Retinal organoids from human pluripotent stem cells (hPSCs) offer a more accessible and reproducible human test platform for evaluating AAV-based gene therapy. In this study, hPSCs were differentiated into retinal organoids composed of various types of retinal cells. The transduction efficiencies of AAV2 and AAV8, which are widely used in clinical trials of inherited retinal diseases, were analyzed using retinal organoids. These results suggest that retinal organoids derived from hPSCs serve as suitable screening platforms owing to their diverse retinal cell types and similarity to the human retina. In summary, we propose an optimal stepwise protocol that includes the generation of retinal organoids and analysis of AAV transduction efficacy, providing a comprehensive approach for evaluating AAV-based gene therapy for retinal diseases.

Research of Change of Heart Rate Variability by Psychological Types before and after Meditation Program (α Version) (명상프로그램(α version) 시행 전 후의 심리유형별 HRV 변화 연구)

  • Kim, Geun-Woo;Bae, Hyo-Sang;Kim, Ji-Hwan;Kim, Byoung-Soo;Lee, Pil-Won;Park, Seong-Sik
    • Journal of Oriental Neuropsychiatry
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    • v.26 no.2
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    • pp.89-102
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    • 2015
  • Objectives: To examine the medical effectiveness of meditation programs ($\alpha$ version) by psychological types. Methods: MBTI, which was created by Katharine Cook Briggs and Isabel Briggs Myers, was used as the Psychological Type test and to investigate psychological temperament and functions and psychological preferences. Heart rate variability was used to test the effectiveness of meditation by investigating time domains (mean HR, SDNN, PSI) and frequence domain parameters (TP, LF, HF, LF or HF norm, Ln (TP or VLF or LF or HF). Results: 1. The autonomic nervous system became active, and both time domains and frequency domains showed positive responses to meditation in heart rate variability tests, without distinction of Psychological Types. 2. In Psychological Types using sensing over intuition for perception, there were positive responses as well as an increase of the parasympathetic nervous system's activeness to meditation for heart rate variability tests, depending on psychological temperaments and psychological functions. 3. In heart rate variability tests by preferences, there was no difference. Extroversion and Introversion types, Sensing over Intuition Types, Thinking over Feeling Types, Judging over Perception Types had an increase of activeness of the parasympathetic nervous system. Therefore, meditation has a positive physical and psychological relaxing effect. Conclusions: A complex meditation program has a positive effect on overall meditation. Especially in the MBTI test, sensing was superior to intuition when people recognized objects. The Sensing, Thinking and Judging type was more advantageous than Intuition, Feeling and Perception, respectively. In the future, a well-designed control study is needed, to develop a suitable meditation for each personality type.

A Study on the Architectural Planning for Improvement of the Healing Environment in Multi-bed Room of General Hospitals (종합병원 다인병실의 치유환경 개선을 위한 건축 계획적 연구)

  • 김용우;양내원
    • Korean Institute of Interior Design Journal
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    • no.36
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    • pp.76-83
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    • 2003
  • The purpose of this study is to know how to improve environment of multi-bed room by investigating and analysing factors influencing to patients. 1 measured stress and satisfaction degrees about patient room for 4ㆍ5ㆍ6ㆍ7 men of domestic general hospital wards. The results of research show that patients of 4 bed room appeared the fewest stress and highest satisfaction degree among patients of other room styles. The patients positioned between two beds can give us more stress and fewer satisfaction than others. These results have proven that 4 bed room patients are offering comfortable environment than any other room types as a healing environment. When patient room area are more than 7.3$M^2$ per 1 person, bed interval space is more than 120cm, there is curtain between bed, transit space such as a toilet were established in patient room, patients' satisfaction appeared high.