• Title/Summary/Keyword: two-body interaction

Search Result 311, Processing Time 0.026 seconds

Dynamic Analysis of Multiple-Body Floating Platforms Coupled with Mooring Lines and Risers

  • Kim Young-Bok;Kim Moo-Hyun
    • Journal of Ship and Ocean Technology
    • /
    • v.9 no.1
    • /
    • pp.11-26
    • /
    • 2005
  • In this study, the program to investigate the multiple body interaction effects between a floating platform and a shuttle tanker considering the coupled effect of hull (FPSO) with mooring lines and risers was developed. The coupled analysis program, which is called WINPOST-MULT using the hydrodynamic analysis results by WAMIT, was made. For the verification of WINPOST-MULT by means of numerical experiments, two multiple-body models of an FPSO-FPSO and an FPSO-shuttle tanker system are adopted. With the FPSO-FPSO model and a two-mass-spring system to idealize two identical bodies for the 100-year storm wave condition in GOM, the numerical simulations were performed to investigate the interaction effects between two identical bodies. For the more reality, the coupled analysis for the FPSO-shuttle tanker model in the tandem arrangement was carried out in the consideration of the environmental condition of the West Africa Sea as a rather mild condition. Through the case studies with interaction effect and without interaction effect by the iteration method and the combined method, it is verified that the program is a very useful tool for the analysis of the interaction problem of multiple-body system and the coupled problem of the hull/mooring/riser.

Experimental Study on the Reduction of Vertical Motion of Floating Body Using Floating-Submerged Bodies Interaction (부유체-몰수체 상호작용을 이용한 부유체 상하운동 저감에 대한 실험적 연구)

  • Shin, Min-Jae;Koo, WeonCheol;Kim, Sung-Jae;Heo, Sanghwan;Min, Eun-Hong
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.54 no.6
    • /
    • pp.485-491
    • /
    • 2017
  • An experimental study on the reduction of vertical motion of floating body using floating-submerged body interaction was performed in a two-dimensional wave channel. The system consisting of a floating and submerged body that only move vertically was modeled. This experiment was designed based on the results of theoretical analysis of two-body interaction. The results showed a tendency to significant reduction of heave RAO of floating body due to submerged body. Various connection line stiffness and dimension of the submerged body were applied to investigate the effect of two-body interaction on the vertical motion of the bodies, Heave RAOs of the floating-submerged body were compared with those of single body. From the comparison study, we obtained an optimum condition of connection line and dimension of submerged body for maximum heave reduction at the resonant period of single body.

The Effect of Body Cathexis on the Clothing Behavior - among Male and Female College Students - (신체만족도에 따른 의복행동에 대한 연구 - 남녀 대학생을 중심으로 -)

  • 임경복
    • The Research Journal of the Costume Culture
    • /
    • v.5 no.2
    • /
    • pp.195-205
    • /
    • 1997
  • The purpose of this study was to identify the effect of genderand body cathexis on clothing behavior (interest in clothing and clothing satisfaction/dissatisfaction). The questionnaire were administered to 395 college students living in Jechon. Data were analyzed by frequency, factor analysis, t-test, ANOVA, two-way ANOVA, Duncan's Multiple Range Test and Pearson's Correlation. The results of this study were as follows : 1) body-cathexis was higher in men than women. In general, students were more satisfied with upper body parts than lower body parts. 2) There was no relationship between interest in cloghing and body-cathexis. But woman showed more interest in clothing than man, therefore sex showed main effect. And there was interaction between sex and body-cathexis on interest in clothing. 3) Clothing satisfaction was devided into aesthetic/economical/practical factors. Among three satisfaction factors, body cathexis has the main effect in economic factor, and there was no interaction. But in aesthetic factor, gender and body-cathexis showed interaction and body-cathexis showed main effect.

  • PDF

Near-body Interaction Enhancement with Distance Perception Matching in Immersive Virtual Environment

  • Yang, Ungyeon;Kim, Nam-Gyu
    • Journal of Multimedia Information System
    • /
    • v.8 no.2
    • /
    • pp.111-120
    • /
    • 2021
  • As recent virtual reality technologies provide a more natural three-dimensional interactive environment, users naturally learn to explore space and interact with synthetic objects. The virtual reality researcher develops a technique that realizes realistic sensory feedback to get appropriate feedback to sense input behavior. Although much recent virtual reality research works extensively consider the human factor, it is not easy to adapt to all new virtual environment contents. Among many human factors, distance perception has been treated as very important in virtual environment interaction accuracy. We study the experiential virtual environment with the feature of the virtual object connected with the real object. We divide the three-dimensional interaction, in which distance perception and behavior have a significant influence, into two types (whole-body movement and direct manipulation) and analyze the real and virtual visual distance perception heterogeneity phenomenon. Also, we propose a statistical correction method that can reduce a near-body movement and manipulation error when changing the interaction location and report the experiment results proving its effectiveness.

A Study of the Effects of the Trunk Angles and the Upper Ann Angles on Workloads in the Lifting Work (들기작업 시 몸통각도와 상완각도가 작업부담에 미치는 영향에 관한 연구)

  • Chang, Seong-Rok;Park, Hyung-Gu
    • Journal of the Korean Society of Safety
    • /
    • v.24 no.2
    • /
    • pp.69-75
    • /
    • 2009
  • It is well-known that lifting capacity of a worker is influenced by body posture during the task. When a task analyst make use of RULA and REBA Trunk and upper arm angles are recorded in a separate item. It means that the interaction between the angles of two body segments may be ignored in a final score. The NLE(NIOSH Lifting Equation) has been used to supplement this problem. However, there is no study to validate the result of RWL (Recommended Workload Limit) under the existence of interactions between trunk and upper arm angles. The goal of this study was to assess the effect of the interaction between trunk and upper arm angles. Three responses, including NMVC(normalized maximum voluntary contraction), RWL(Recommended Weight Limit) and subjective judgment in psychophysical method (Borg's scale), were recorded according to the combinations of three trunk angles and nine upper arm angles. The results showed that lifting capacity is highly influenced by interaction of two body segments(trunk and upper arm). It means that the task workload has to be analyzed along with the interaction of trunk angles and upper arm angles when the task analyst assesses potential risk factors on the postures. This study may be able to be a fundamental study to develop an assessment method for lifting task analyses according to body postures.

Study on the preconditioning method of a finite element combined formulation for fluid-structure interaction (유체-구조물 상호작용을 위한 유한요소 결합공식화의 예조건화에 대한 연구)

  • Choi, Hyoung-G.
    • 한국전산유체공학회:학술대회논문집
    • /
    • 2008.03b
    • /
    • pp.597-600
    • /
    • 2008
  • Preconditioners for a two-dimensional combined finite element formulation have been devised and tested for fluid-structure interaction (FSI) problems. The FSI code simulating the interaction of a elastic body with an unsteady flow is based on P2P1 finite element combined formulation. It has been shown that two preconditioners among them perform well with respect to computational memory and convergence for a bench-mark problem. Based on the verification of the preconditioners for the two-dimensional combined formulation, four preconditioners are proposed for the problem of an elastic body interacting with a flow.

  • PDF

Self-controller of Saam Acupuncture Viewed from the Aspect of the Five Viscera Interaction (오장상섭(五臟相涉)의 측면에서 살펴본 사암침법(舍岩鍼法)의 억관(抑官)과 보관(補官))

  • Oh, Jun-Ho
    • Korean Journal of Acupuncture
    • /
    • v.28 no.3
    • /
    • pp.127-140
    • /
    • 2011
  • Objectives : The aim of this study is to regulate the medical meaning about Kwan [self-denial] which is used by Jeongkyeok [reinforcing the weak body part] and Seungkyeok [consolidating the weak body part while inducing cathartic action of comparatively stronger body part] of Saam Acupuncture in common. Methods : This study generalized the method of understanding 'The Five Viscera Interaction' in Oriental Medicine from the perspective of literature and considering human organs in the medical context. Results and Conclusions : 1. There existed 'The Five Viscera Interaction' theory regulating the correlation between the five viscera headed by "Nankyeong" in the traditional Oriental medicine. The five viscera interaction theory was used as the standard of judging the symptom and the prognosis of a disease in the history of Oriental medicine and further used even as the method of preventing and treating diseases. 2. The treatment included in "Biyebaekyobang", a medical book in the period of Goryeo, can be rated as the most developmental form of medical theory which applied 'the five viscera interaction theory' to clinical treatment. The author of "Biyebaekyobang" managed to break away from the schematism of the five viscera interaction through the method of treating two internal organs using one organ treatment and applying the individually different relations between organs. "Biyebaekyobang" shows close similarities to Saam Acupuncture. 3. The organs handled in Saam Acupuncture has a significance in that it put forward the part which had not been aggressively dealt with in medical history up until then.

The Visual Effect Evaluation by Skirt Silhouette and Length, and Wearer's BMI Categories (BMI별 스커트 실루엣과 길이에 따른 시각적 효과 평가)

  • Li, Qi;Nam, Young-Ran;Kim, Dong-Eun
    • Fashion & Textile Research Journal
    • /
    • v.22 no.6
    • /
    • pp.812-825
    • /
    • 2020
  • This study compared and analyzed the interaction visual effect of skirt silhouettes and skirt length by body mass index. This study provides basic data for women in their 20s and 30s to choose suitable skirts for their image. Twelve skirts were made, consisting of two categories of body mass index, three types of skirt silhouette and two levels of skirt length. Men and women in their 20s and 30s evaluated the visual effects of the experimental skirts using a questionnaire. The interaction effect of the visual effect following the skirt's length and silhouette by body mass index were analyzed by three-way ANOVA. Overall, a shorter the body and lower body length resulted in better vertical effects in normal weight. In terms of horizontal effects, such as lower body thickness and full-body shape, the 40 cm skirt, 50 cm tight, and A-line skirt were generally shown as better images. Skirt length helped supplement body type rather than silhouette in the overweight section. When the length was 40 cm, three skirts showed a more positive image. This study provide results for women in their 20s and 30s to choose skirts that are suitable for their image.

Hydrodynamic analysis of a floating body with an open chamber using a 2D fully nonlinear numerical wave tank

  • Uzair, Ahmed Syed;Koo, Weon-Cheol
    • International Journal of Naval Architecture and Ocean Engineering
    • /
    • v.4 no.3
    • /
    • pp.281-290
    • /
    • 2012
  • Hydrodynamic analysis of a surface-piercing body with an open chamber was performed with incident regular waves and forced-heaving body motions. The floating body was simulated in the time domain using a 2D fully nonlinear numerical wave tank (NWT) technique based on potential theory. This paper focuses on the hydrodynamic behavior of the free surfaces inside the chamber for various input conditions, including a two-input system: both incident wave profiles and forced body velocities were implemented in order to calculate the maximum surface elevations for the respective inputs and evaluate their interactions. An appropriate equivalent linear or quadratic viscous damping coefficient, which was selected from experimental data, was employed on the free surface boundary inside the chamber to account for the viscous energy loss on the system. Then a comprehensive parametric study was performed to investigate the nonlinear behavior of the wave-body interaction.

Exploration of power take off in wave energy converters with two-body interaction

  • Wang, Hao;Sitanggang, Khairil;Falzarano, Jeffrey
    • Ocean Systems Engineering
    • /
    • v.7 no.2
    • /
    • pp.89-106
    • /
    • 2017
  • The study explores a novel design of wave energy converter (WEC) that utilizes the interaction between an inside heaving vertical cylinder with an outside fixed hollow cylinder. This design originates from the oscillating water column (OWC) type WEC but replaces the pneumatic power take off (PTO) through the Wells turbine with the hydrodynamic PTO through the inside heaving cylinder. To effectively evaluate the maximum power output, the system has been modeled in the hydrodynamic software AQWA (developed by ANSYS Inc) that has accumulated extensive offshore industry users. Ranges of the PTO parameters have been examined to make sure that proper linear damping can be implemented to simulate the PTO force. Comparing the efficiency of the pneumatic PTO with the hydrodynamic PTO, it appears that the hydrodynamic PTO is more promising than the traditional Wells turbine for an OWC system.