• Title/Summary/Keyword: Attracting

Search Result 1,702, Processing Time 0.026 seconds

Development of Image sensor based automatic sun tracking system (이미지 센서기반의 태양광 자동 추적 시스템 개발)

  • Kim, Se Yoon;An, Seo Kil;Kim, Sung Ho
    • Smart Media Journal
    • /
    • v.3 no.1
    • /
    • pp.22-27
    • /
    • 2014
  • Recently, domestic energy environment is facing new challenges owing to the depletion of fossil fuel such as oil. Renewable energy resources including solar and wind energy are attracting more interests than ever before. However, solar power system is costly in comparison with the conventional power generation systems and also the energy density is low. Furthermore, large area is required in order to install solar power system. Generally, performance of solar power system is affected by weather conditions and alignment of sun and the solar cell modules. In this study, a new type of sun tracking system for solar power system is proposed. To verify the feasibility of the proposed system, actual implementation of prototype system and experiments are carried out.

Wake Region Estimation of Artificial Reefs using Wake Volume Diagrams (후류체적선도를 이용한 인공어초 후류역 평가)

  • KIM, Dongha;JUNG, Somi;NA, Won-Bae
    • Journal of Fisheries and Marine Sciences Education
    • /
    • v.28 no.4
    • /
    • pp.1042-1056
    • /
    • 2016
  • To evaluate the wake regions of six artificial reefs (ARs) frequently used in the marine forest creation project in Korea, we consider the effect of water flow directions on the wake regions and accordingly propose a wake region diagram, which is characterized by parameters such as wake volume fluctuations, averaged wake volume, fundamental symmetric angle, secure angle, and principal direction. To demonstrate the parameters, seven water flow directions (0 to $90^{\circ}$) were considered and consequently the variations in wake volumes were investigated by using the concept of wake volume, adopting element-based finite volume method, and utilizing numerical flow domain and boundary conditions. From the analysis results, it was shown that the wake region diagrams have a period of either 45 or $90^{\circ}$ according to the geometrical symmetry of each artificial reef. Also, it was found that the secure angle ranges fluctuate depending on the shapes and sizes of the artificial reefs considered. Thus, it is demanded to consider those parameters during installation of artificial reefs for establishing a larger wake region and accordingly attracting more marine fauna and flora in the region.

The Design of the Feedback Control System of Electromagnetic Suspension Using Kalman Filter

  • Jo, Jeong-Min;Han, Young-Jae;Lee, Chang-Young
    • International Journal of Railway
    • /
    • v.4 no.4
    • /
    • pp.93-96
    • /
    • 2011
  • The basic element of the EMS suspension is the electromagnet system, which suspends the vehicle without contact by attracting forces to the rails at the guideway. The suspension of a vehicle by attractive magnetic forces is inherently unstable and consequently it is continuously adjusted by the strength of the suspending electromagnet from rail irregularity and bending of the guideway. In order to improve reliable tracking, it needs to get feedback signals without measurement delay time. In this paper the concept of feedback control system with Kalman Filter in EMS is proposed. The input signals in the feedback control system are an air-gap and an acceleration signal. The air-gap signal with noise from the gap sensor is transformed to the filtered air-gap signal y without measurement delay time by using Kalman Filter. The filtered air-gap signal is transformed to a relative velocity and a relative acceleration signal. Then it multiplies these values by gain matrix in order to get the actuator's reference voltage value. The simulation results show that the dynamic responses of the suspension system can be improved by reducing the influence of measurement delay time of air-gap signals.

  • PDF

Flattening simulations of 3D thick sheets made of fiber composite materials

  • Morioka, Kotaro;Ohtake, Yutaka;Suzuki, Hiromasa;Nagai, Yukie;Hishida, Hiroyuki;Inagaki, Koichi;Nakamura, Takeshi;Watanabe, Fumiaki
    • Journal of Computational Design and Engineering
    • /
    • v.2 no.2
    • /
    • pp.88-95
    • /
    • 2015
  • Recently, fiber composite materials have been attracting attention from industry because of their remarkable material characteristics, including light weight and high stiffness. However, the costs of products composed of fiber materials remain high because of the lack of effective manufacturing and designing technologies. To improve the relevant design technology, this paper proposes a novel simulation method for deforming fiber materials. Specifically, given a 3D model with constant thickness and known fiber orientation, the proposed method simulates the deformation of a model made of thick fiber-material. The method separates a 3D sheet model into two surfaces and then flattens these surfaces into two dimensional planes by a parameterization method with involves cross vector fields. The cross vector fields are generated by propagating the given fiber orientations specified at several important points on the 3D model. Integration of the cross vector fields gives parameterization with low-stretch and low-distortion.

A Study of Movement Expression in Fashion Design and Its Design Development (복식디자인에 나타난 움직임의 표현 분석과 디자인 개발)

  • Lee, Hyun-Jung;Choi, Yoon-Mi
    • The Research Journal of the Costume Culture
    • /
    • v.14 no.1
    • /
    • pp.128-141
    • /
    • 2006
  • The purposes of this study are to consider characteristics of 'movement expression' that are not discovered in preceeding design studies in order to suggest 'movement expression' as a design formative principal and to make clothes which follows this idea. For the method of this study I used various literature about 'movement expression' as theoretical background and analyzed modern clothing in which 'movement expression' is expressed by collecting magazines including foreign collections from 1989 to 2004 and searching the internet. The results obtained from this study is as follows. First, clothing in which 'movement expression' is expressed removes monotony and tedium of clothing design, provides visual interest and satisfaction for clothing, and delivers designers' concept effectively by attracting a gaze quickly. And It is suggested a new division of 'movement expression' through analysis of the 'movement expression' expressed in clothing. It included the intentional movement by wearers, which is the 'movement expression' of broader meaning such as changes of form or position by a certain operation and changes of existence or function. This movement is not fixed and repeated but changes continuously. As a result of including the design expressing the intentional movement by wearers, one's own personality can be expressed more effectively. It is presented a design which has changeable movement expression continuously.

  • PDF

Photodegradation of Rhodamine B in $TiO_2$ suspension

  • Na, Young-Soo;Kim, Ji-Hye;Lee, Tae-Kyung;Lee, Song-Woo;Song, Seung-Koo
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
    • /
    • v.10 no.S_3
    • /
    • pp.149-155
    • /
    • 2001
  • In recent years, rapid technological advances in the textile and dyeing industry have yielded benefits to society but have also generated new and significant environmental problems. The treatment alternatives applicable for the removal of color vary, depending upon the type of dye wastewater Advanced oxidation processes are considered to provide more permanent merits. One of these oxidation treatments attracting much attention is photocatalytic oxidation, which uses TiO$_2$ due to its non-toxic, insoluble liquid as well as a highly reactive nature under UV irradiation. This study sets out to demonstrate the effect of photocatalyst dosage, dye concentrations, pH and light intensity on color removal efficiency under aerobic conditions. The results of this study show Rhodamine B(RhB) was not decolorized when a dye solution was exposed only to air or treated by TiO$_2$ only In the presence of both TiO$_2$ and UV light, however, the presence of RhB decreased up to 95 % within 60minutes. The more addition TiO$_2$ and the more diluted dye solution, showed a higher removal rate.

  • PDF

A Study of Visitor Behavior in Informal Learning Setting: A Natural History Museum

  • Kim, Chan-Jong;Lee, Chang-Zin;Shin, Myeong-Kyeong
    • Journal of the Korean earth science society
    • /
    • v.25 no.3
    • /
    • pp.142-151
    • /
    • 2004
  • This study was designed to determine whether visitor behavior at science museums differs across various exhibit styles and between Family and Non Family groups. Eight exhibits in the natural history sections of the national science museum located in Daejeon were identified to have distinctive characteristics and styles. At each selected exhibit, visitor behavior was observed for an hour. An average of eighty people stopped by each exhibit. Descriptive analyses of visitors behaviors showed that: 1) families spent more time than non-family visitors; 2) families paid more attention to exhibits, for instance, they talked and commented about the exhibits; 3) exhibit characteristics related to holding power and attention span; 4) families more frequently visited exhibits related to school curriculum rather than ones that looked attractive, fun or novel. Visitors did not play with sensory simulation types of exhibits as much as expected. This implicates that exhibit style does not guarantee long visitors holding time and attracting power. Non-significant results are explained in terms of environmental and exhibit-related factors. Several potential factors including visitor factors, setting factors, and exhibit factors are discussed and explored with topics proposed for future study.

Globalization and Regional Growth Gaps: A Korean Case (세계화와 한국의 지역간 성장격차)

  • Kwak, Ro-Sung;Chae, Hee Bong
    • Journal of the Economic Geographical Society of Korea
    • /
    • v.18 no.2
    • /
    • pp.152-167
    • /
    • 2015
  • This paper analyzes the effects of globalization on growth gaps between regions. Using openness and FDI as measures of globalzation in Korean 16 broad autonomous territories the study estimates the effects of the variables on growth gaps between regions. Estimation results show that FDI is significant in explaining the regional gaps while openness is not. The results of the study reveal that attracting FDI to weaker regions, especially the investment in New Industries, is inevitable to resolve growth gaps and for balanced growth among regions. Also, policy makers should use FDI as an important tool for correcting regional gaps as well as the vehicles for regional development.

  • PDF

A Study on the Effect of Wineglass to the Wine Tasting -Focussing on Riedel Glass- (글라스가 와인 테이스팅에 미치는 영향 -리델 글라스를 중심으로-)

  • Lee, U-Joo
    • Culinary science and hospitality research
    • /
    • v.10 no.1
    • /
    • pp.64-81
    • /
    • 2004
  • Recently, the demand for utensils related to wine business has been growing from the wine consumers in Korea in order to enjoy flavor of wine more profoundly. This study propose a theory about the five senses that had been issued frequently in wine world attracting an attention of ever-changing food culture. In addition, it is to help sommeliers and devotes to learn the knowledge about the wine. To fully appreciate the different grape varieties and the subtle characteristics of wines, it is essential to have a glass with shape if fine-tuned for the purpose. The shape is responsible for the quality and intensity of the bouquet and the flow of the wine. This study has been performed with Riedel glass that has been appreciated as one of the finest wineglass in the world to investigate the effect of glass to the wine tasting. This study should be followed by further study with other tasting glass such as INAO and Le Taster glass to be generalized. The study is also needed about not only wineglass but wine accessories such as cork-screw, decanting and wine cooler.

  • PDF

A Comparative Study on ROI between Traditional and Web Services based ASP : A BSC Approach (웹 서비스 기술 도입에 따른 ASP 사업 투자효과의 향상에 대한 비교 연구 : 균형성과표 기반 분석)

  • Yang Sung-Byung;Park Sang-Un;Song Yong-Uk;Kang Ju-Young
    • Journal of Information Technology Applications and Management
    • /
    • v.13 no.1
    • /
    • pp.17-38
    • /
    • 2006
  • Recently, ASP business models based on Web services are attracting considerable attention and regarded as the next generation of the ASP business models. It is, however, undesirable for ASP users to adopt them simply because the Web services are the new trend in the IT world. Instead, an in-depth comparison of the benefits against the costs between the Web services based ASP business models and the traditional models are required. Furthermore, it is desirable that this comparative analysis should be applied from the ASP users' viewpoints rather than those of the government or ASP providers. So, we have applied a comparative ROI (Return on Investment) analysis from the ASP users' perspective and shown that the Web services based ASP business models (382%) are superior to the traditional models (280%) in terms of ROI. We have also employed Balanced Scorecard (BSC) framework to keep the balance between tangible and intangible benefits considering the characteristics of IT value measurement.

  • PDF