• Title/Summary/Keyword: light elements

검색결과 838건 처리시간 0.028초

투명성을 이용한 현대 패션디자인의 미적 특성 (Aesthetic Characteristics of Modern Fashion Design with Emphasis on Transparency)

  • 김선영
    • 대한가정학회지
    • /
    • 제46권8호
    • /
    • pp.17-26
    • /
    • 2008
  • The purpose of this study was to identify the aesthetic characteristics of modern fashion design use with a particular focus on transparency, and to help create future vision and feature. As part of the methodology for this study, I examined the concept of transparency, its characteristics and how it was expressed through art, architecture and other designs using literature research. Furthermore, I performed justifiable analysis on modern fashion design which used transparency from the 1990s till present. The following concepts were deciphered from information: Firstly, the concept of purity was highlighted. The emphasis here was to enhance the body's natural beauty with simple silhouettes that do not restrict its curves, using light materials such as clear vinyl, semi-clear materials or thin chiffon. Secondly, to express sensuality by exposing the body's curves with tight wrapping using clear materials, or with indirect and symbolic see-through techniques using contrasting clear, semi-clear and opaque materials. Thirdly, to express futurism through cyber and electronic images using high tech or shiny materials such as metal or holograms. Mechanical movements or effects of light are also used. Fourthly, to express playful characteristic by promoting surprises and disharmony that contradict with traditional techniques. This is carried out by intentionally exaggerating certain portions of clothes through disorder elements or confusion, and unsymmetrical shapes which destruct the human body's normal form.

Excessive CNO yield of the non-rotating massive Pop III stars

  • Kye, Changwoo;Yoon, Sung-Chul
    • 천문학회보
    • /
    • 제41권1호
    • /
    • pp.76.1-76.1
    • /
    • 2016
  • During the last decade, high-resolution spectra of many very metal-poor (VMP) stars have been observed and their surface compositions have been measured. The abundance patterns of the VMP stars strongly constrain the nucleosynthesis of Pop III stars because they born from material enriched by supernovae or wind ejecta of Pop III stars. The observations show overabundances of light elements like C, N, O, Na, Mg and Al and very low $C^{12}/C^{13}$ ratios. These results indicate that mixing between the H-burning and He-burning region occurred in Pop III stars. To explain these observational results, we performed 1D stellar evolution simulations for non-rotating Pop III stars with ZAMS masses ranging from $20M_{\Box}$ to $50M_{\Box}$ and various overshooting parameters. In our grid calculation, convective mixing between helium burning layers and the hydrogen burning shell generally occurred in models with masses less than $40M_{\Box}$ without rotation and these models show an excess of light element abundances. From this result, it is expected that we could explain the observed abundance patterns with convective mixing in non-rotating massive Pop III stars and we do not necessarily have to invoke rotational mixing.

  • PDF

스베르펜(Sverre Fehn) 건축에 나타난 『플랫폼 건축(Platform Architecture)』 개념과 디자인 특성에 관한 연구 (A Study on Concept and Design Characteristics of 『Platform Architecture』 in the Architecture of Sverre Fehn)

  • 박현주;김종진
    • 한국실내디자인학회논문집
    • /
    • 제21권6호
    • /
    • pp.92-99
    • /
    • 2012
  • The Norwegian architect, Sverre Fehn who was born in 1924 and died in 2009 designed various buildings in his country. Since he studied architecture, he had been interested in the domestic/local architectural environment as well as international modern movement such as CIAM. Pavilion of the Nordic Nations designed in 1960s gave him world reputation for the peculiar design characteristic in which Scandinavian tradition and modern design were integrated. Fehn introduced his unique architectural philosophy that is called 'Platform Architecture'. This concept is based on the Fehn's long-term interest in the philosophy of Genius Loci and place-specificity. It consists of three theoretical elements: Tectonic of Place, Horizontality of Space and Visual-Perception by Light. This paper focuses on three case projects: Villa Busk in 1990, Norwegian Glacier Museum in 1991, Aukrust Museum in 1993. It is aimed to discover differences as well as similarities of the projects, and ultimately to summarize the cases under the light of 'Platform Architecture'. As a conclusion, it is found that each case project has unique spatializing method to organize the given place and program by 'Platform' architectural design. 'Platform Architecture' is still relevant in the contemporary architecture and interior design because of its deep consideration on place, environment and human.

  • PDF

복합센서를 이용한 화재자현 콘크리트의 개발 (Development of Fire-Diagnosis Concrete using Composite Sensors)

  • 최영화;김이성;박강근
    • 한국공간구조학회논문집
    • /
    • 제10권4호
    • /
    • pp.85-92
    • /
    • 2010
  • 콘크리트의 사용은 건축 및 토목분야에서 널리 사용되어 왔으며, 센서는 콘크리트에 기능적 특성을 위해 사용되어 왔다. 손상을 스스로 나타내는 콘크리트는 이미 개발되고 있는 중에 있다. 본 연구에서 온도보상센서는 금속의 선형팽창과 체적변형을 이용한 센서이다. LED는 광센서로 고휘도이며, 이들 센서의 가격은 저가격이다. 화재하중으로 인하여 콘크리트 보의 온도보상센서가 동작하는 동안 지상 보의 LED동작으로 콘크리트 부재의 온도상승을 예측한다. 본 연구에서는 부재의 손상감지를 위해 간단한 계측방법을 이용하여 화재자현을 스스로 나타내는 콘크리트 보를 개발하기 위한 기초적 연구이다.

  • PDF

시각 셀 OOK 변조 : MIMO CamCom 연구 사례 (Visual Cell OOK Modulation : A Case Study of MIMO CamCom)

  • 레투안남;장영민
    • 한국통신학회논문지
    • /
    • 제38C권9호
    • /
    • pp.781-786
    • /
    • 2013
  • Multiplexing information over parallel data channels based on RF MIMO concept is possible to achieve considerable data rates over large transmission ranges with just a single transmitting element. Visual multiplexing MIMO techniques will send independent streams of bits using the multiple elements of the light transmitter array and recording over a group of camera pixels can further enhance the data rates. The proposed system is a combination of the reliance on computer vision algorithms for tracking and OOK cell frame modulation. LED array are controlled to transmit message in the form of digital information using ON-OFF signaling with ON-OFF pulses (ON = bit 1, OFF = bit 0). A camera captures image frames of the array which are then individually processed and sequentially decoded to retrieve data. To demodulated data transmission, a motion tracking algorithm is implemented in OpenCV (Open source Computer Vision library) to classify the transmission pattern. One of the most advantages of proposed architecture is Computer Vision (CV) based image analysis techniques which can be used to spatially separate signals and remove interferences from ambient light. It will be the future challenges and opportunities for mobile communication networking research.

Study on the design and experimental verification of multilayer radiation shield against mixed neutrons and γ-rays

  • Hu, Guang;Hu, Huasi;Yang, Quanzhan;Yu, Bo;Sun, Weiqiang
    • Nuclear Engineering and Technology
    • /
    • 제52권1호
    • /
    • pp.178-184
    • /
    • 2020
  • The traditional methods for radiation shield design always only focus on either the structure or the components of the shields rather than both of them at the same time, which largely affects the shielding performance of the facilities, so in this paper, a novel method for designing the structure and components of shields simultaneously is put forward to enhance the shielding ability. The method is developed by using the genetic algorithm (GA) and the MCNP software. In the research, six types of shielding materials with different combinations of elements such as polyethylene (PE), lead (Pb) and Boron compounds are applied to the radiation shield design, and the performance of each material is analyzed and compared. Then two typical materials are selected based on the experiment result of the six samples, which are later verified by the Compact Accelerator Neutron Source (CANS) facility. By using this method, the optimal result can be reached rapidly, and since the design progress is semi-automatic for most procedures are completed by computer, the method saves time and improves accuracy.

Photoelectrochemical Water Oxidation and $CO_2$ Conversion for Artificial Photosynthesis

  • Park, Hyunwoong
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
    • /
    • pp.70-70
    • /
    • 2013
  • As the costs of carbon-footprinetd fuels grow continuously and simultaneously atmospheric carbon dioxide concentration increases, solar fuels are receiving growing attention as alternative clean energy carriers. These fuels include molecular hydrogen and hydrogen peroxide produced from water, and hydrocarbons converted from carbon dioxide. For high efficiency solar fuel production, not only light absorbers (oxide semiconductors, Si, inorganic complexes, etc) should absorb most sunlight, but also charge separation and interfacial charge transfers need to occur efficiently. With this in mind, this talk will introduce the fundamentals of solar fuel production and artificial photosynthesis, and then discuss in detail on photoelectrochemical (PEC) water splitting and CO2 conversion. This talk largely divides into two section: PEC water oxidation and PEC CO2 reduction. The former is very important for proton-coupled electron transfer to CO2. For this oxidation, a variety of oxide semiconductors have been tested including TiO2, ZnO, WO3, BiVO4, and Fe2O3. Although they are essentially capable of oxidizing water into molecular oxygen, the efficiency is very low primarily because of high overpotentials and slow kinetics. This challenge has been overcome by coupling with oxygen evolving catalysts (OECs) and/or doping donor elements. In the latter, surface-modified p-Si electrodes are fabricated to absorb visible light and catalyze the CO2 reduction. For modification, metal nanoparticles are electrodeposited on the p-Si and their PEC performance is compared.

  • PDF

Direct Measurement of Diffusion Length in Mixed Lead-halide Perovskite Films Using Scanning Photocurrent Microscopy

  • Kim, Ahram;Son, Byung Hee;Kim, Hwan Sik;Ahn, Yeong Hwan
    • Current Optics and Photonics
    • /
    • 제2권6호
    • /
    • pp.514-518
    • /
    • 2018
  • Carrier diffusion length in the light-sensitive material is one of the key elements in improving the light-current conversion efficiency of solar-cell devices. In this paper, we measured the carrier diffusion length in lead-halide perovskite ($MAPbI_3$) and mixed lead-halide ($MAPbI_{3-x}Cl_x$) perovskite devices using scanning photocurrent microscopy (SPCM). The SPCM signal decreased as we moved the focused laser spot away from the metal contact. By fitting the data with a simple exponential curve, we extracted the carrier diffusion length of each perovskite film. Importantly, the diffusion length of the mixed-halide perovskite was higher than that of the halide perovskite film by a factor of 3 to 6; this is consistent with the general expectation that the carrier mobility will be higher in the case of the mixed lead-halide perovskites. Finally, the diffusion length was investigated as a function of applied bias for both samples, and analyzed successfully in terms of the drift-diffusion model.

Design and Lithographic Fabrication of Elliptical Zone Plate Array with High Fill Factor

  • Anh, Nguyen Nu Hoang;Rhee, Hyug-Gyo;Ghim, Young-Sik
    • Current Optics and Photonics
    • /
    • 제5권1호
    • /
    • pp.8-15
    • /
    • 2021
  • An elliptical zone plate (EZP) array is important in off-axis optical systems because it provides two advantages. First, the residual beam and the main source are not focused in the same direction and second, the light from the observation plane is not reflected back towards the beam source. However, the fill factor of the previous EZP array was about 76% which was a little low. Hence, this EZP array could not collect the maximum amount of illumination light, which affected the overall optical performance of the lens array. In this study, we propose a new EZP array design with a 97.5% fill factor used in off-axis imaging system for enhancement of brightness and contrast. Then, direct laser lithography was used to fabricate the high fill factor EZP array by moving the XY linear stage of the system in a zigzag motion. The imaging properties of the proposed EZP array were experimentally verified at the focal plane and compared with the previous model.

전해 이온화와 자외선광을 이용한 사파이어 화학기계적 연마의 재료제거 효율 향상에 관한 기초 연구 (Basic Study on the Improvement of Material Removal Efficiency of Sapphire CMP Using Electrolytic Ionization and Ultraviolet Light)

  • 박성현;이현섭
    • Tribology and Lubricants
    • /
    • 제37권6호
    • /
    • pp.208-212
    • /
    • 2021
  • Chemical mechanical polishing (CMP) is a key technology used for the global planarization of thin films in semiconductor production and smoothing the surface of substrate materials. CMP is a type of hybrid process using a material removal mechanism that forms a chemically reacted layer on the surface of a material owing to chemical elements included in a slurry and mechanically removes the chemically reacted layer using abrasive particles. Sapphire is known as a material that requires considerable time to remove materials through CMP owing to its high hardness and chemical stability. This study introduces a technology using electrolytic ionization and ultraviolet (UV) light in sapphire CMP and compares it with the existing CMP method from the perspective of the material removal rate (MRR). The technology proposed in the study experimentally confirms that the MRR of sapphire CMP can be increased by approximately 29.9, which is judged as a result of the generation of hydroxyl radicals (·OH) in the slurry. In the future, studies from various perspectives, such as the material removal mechanism and surface chemical reaction analysis of CMP technology using electrolytic ionization and UV, are required, and a tribological approach is also required to understand the mechanical removal of chemically reacted layers.