• Title/Summary/Keyword: natural phenomenon

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A Study on the Asian Dust Phenomenon Found in the Historical Records of Korea Prior to the 20th Century (20세기 이전 한국의 역사 기록에서 확인되는 황사 현상)

  • Jeon, Junhyeok
    • Atmosphere
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    • v.28 no.4
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    • pp.491-507
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    • 2018
  • This study collected and analyzed records related to the Asian dust phenomenon in Korean history books. I collected a wide range of records from diverse sources and identified data for analysis. 290 records were selected through this process. These records provide a variety of information including the occurrence time and duration of the phenomenon, other natural phenomenon occurring at the same date, descriptions of the phenomenon, and so on. Reports on, Asian dust in the historical records was not continuous or uniform. However, their appearance in certain months of the year is similar to that observed in modern times. In addition, I collected 90 records showing it that can be largely divided into two viewpoints which they were a natural calamity or an unusual phenomenon. Generally, natural phenomenons in historical books are mostly recorded in viewpoint of unusual phenomenon. Nevertheless, research result verified the record as actual observational data. Consequentially, it also indicates that this data is important for research from a meteorological point of view. I think that the data collected through this study can be helpful to modern meteorological studies related to the Asian dust phenomenon.

A Study on the Visual Phenomenon of Natural Light in Interior Space (실내공간에 있어 자연광에 의한 시지각적 현상에 관한 연구)

  • 김주연
    • Korean Institute of Interior Design Journal
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    • no.13
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    • pp.130-138
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    • 1997
  • This study is to present the visual phenomenon of natural light in the interior space. The continuously changing natural light define the visual phenomenon of the architectural space. First, the objective of this study was finding the importance of the visual phenomena which were generated from correlating natural right with the interior space. And the second was to categorize the factors of the visual phenomenon which can be useful factors for modern interior design practice. As a result of this study, two visual phenomena were classified. First; territorial phenomenon: dividing, partitioning, and sectioning by natural light, Second; phenomena by the inflow methods of natural light; a) by direct inflow; transparency, expansion, and floating, b) by filtering fixtures; the architectural structure, color, and the transluscent material, c) by dramatic spacial present of natural light, d) by the sense of direction of naturel light; continuity, and transformatiov. Found and classified each factor is not presented by itself, rather compounded forms. Because of the limited analysis of modern buildings, these found visual factors can not represent all phenomena. But if we practice these finding factors to design present interior space, it is sure of being very valuable factors to re-introduce the overlooked natural light into interior space.

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A Study on the Phenomenon of Natural Zoning under COL Storage Policy

  • Lim, Sang-Gyu
    • Journal of the Korean Operations Research and Management Science Society
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    • v.17 no.1
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    • pp.127-134
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    • 1992
  • In this paper, we first examine the stochastic behavior associated with storage/retrieval process under COL policy, and give analytical results such as the limiting distributions of the number of items in the system and the expected travel distance. We also investigate the phenomenon of natural zoning, that is, the tendency of similar items to group themselves together, when two types of items with different turnover rates are stored and retrieved. Natural zoning refers to this grouping occurring under the seemingly unbiased policy COL. We show that zoning can occur naturally with batch arrivals to the storage system.

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Is 'Dry Changma' a Case of Contradictio In Adjecto?: Changma and Natural Kinds ('마른 장마'는 진정 형용모순인가?: 장마와 자연종)

A Study on the Frequency Convergence Phenomenon in a Rotating Circular Plate with Slots (슬롯을 갖는 회전 원판의 주파수 수렴 현상에 대한 연구)

  • Hwang, Seoung-Tack;Kim, Seong-Jin;Yoo, Jeong-Hoon;Lee, Seung-Yop
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.20 no.12
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    • pp.1153-1160
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    • 2010
  • A circular plate is the main part of a circular saw blade, which is widely used in industrial cutting tools. In experiments using a circular saw containing slots, we observed that a number of natural frequencies are simultaneously emerged in specific frequency regions. The interesting phenomenon is called the frequency convergence. Effects of design parameters such as the number, the length and the width of slots, on the frequency-convergence phenomenon are analyzed by FEM simulations using ALGOR. The frequency-convergence phenomenon will be intensified when the number, length and width of slots increase.

Progressive collapse of reinforced concrete structures

  • Yagob, O.;Galal, K.;Naumoski, N.
    • Structural Engineering and Mechanics
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    • v.32 no.6
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    • pp.771-786
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    • 2009
  • In the past few decades, effects of natural hazards, such as earthquakes and wind, on existing structures have attracted the attention of researchers and designers. More recently, however, the phenomenon of progressive collapse is becoming more recognized in the field of structural engineering. In practice, the phenomenon can result from a number of abnormal loading events, such as bomb explosions, car bombs, accidental fires, accidental blast loadings, natural hazards, faulty design and construction practices, and premeditated terrorist acts. Progressive collapse can result not only in disproportionate structural failure, but also disproportionate loss of life and injuries. This paper provides an up-to-date comprehensive review of this phenomenon and its momentousness in structural engineering communities. The literature reveals that although the phenomenon of progressive collapse of buildings is receiving considerable attention in the professional engineering community, more research work is still needed in this field to develop a new methodology for efficient and inexpensive design to better protect buildings against progressive collapse.

Unsteady Single-Phase Natural Circulation Flow Mixing Prediction Using CATHARE Three-Dimensional Capabilities

  • Salah, Anis Bousbia;Vlassenbroeck, Jacques
    • Nuclear Engineering and Technology
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    • v.49 no.3
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    • pp.466-475
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    • 2017
  • Coolant mixing under natural circulation flow regime constitutes a key parameter that may play a role in the course of an accidental transient in a nuclear pressurized water reactor. This issue has motivated some experimental investigations carried out within the OECD/NEA PKL projects. The aim was to assess the coolant mixing phenomenon in the reactor pressure vessel downcomer and the core lower plenum under several asymmetric steady and unsteady flow conditions, and to provide experimental data for code validations. Former studies addressed the mixing phenomenon using, on the one hand, one-dimensional computational approaches with cross flows that are not fully validated under transient conditions and, on the other hand, expensive computational fluid dynamic tools that are not always justified for large-scale macroscopic phenomena. In the current framework, an unsteady coolant mixing experiment carried out in the Rossendorf coolant mixing test facility is simulated using the three-dimensional porous media capabilities of the thermal-hydraulic system CATHARE code. The current study allows highlighting the current capabilities of these codes and their suitability for reproducing the main phenomena occurring during asymmetric transient natural circulation mixing conditions.

A Study on the Pharmaceutical & Chemical Characteristics and Analysis of Natural Curcumin Extract (천연 강황 추출물의 약리, 화학적 특성 및 분석)

  • Sung, Ki-Chun
    • Journal of the Korean Applied Science and Technology
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    • v.28 no.4
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    • pp.393-401
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    • 2011
  • Natural Curcumin belongs to Zingiber Officinale Roscoe was known to possess natural odor, natural taste, natural color, and other pharmaceutical & chemical characteristics. Natural Curcumin extract was made to use ethanol as a solvent was to show a yellow color having state of solid powder and an active component. Natural Curcumin extract tested pharmaceutical & chemical experiment to dilute in curcumin 1%-water solution. Curcumin extract tested antimicrobial experiment using microbe, and tested dye experiment using fiber. Some conclusions in the result of characteristics experiment was obtained as follow. The result of antimicrobial experiment showed that the growth of staphylococcus aureus (ATCC-001) and aspergillus niger (ATCC-002) as microbes decreased according to passage of time. This phenomenon could know that Curcumin compoment showed influence to antimicrobial effect. Also, the result of dye experiment showed that cotton and sick with fiber dyeing dyed in direction of dark yellow color. This phenomenon could know that Curcumin extract showed influence to dyeing effect in observation of optical electron microscope(OEM.) The result of instrument analysis ascertained inorganic components of K(53.300ppm), Na(1.150ppm), Ca(0.711ppm), Ti(0.351ppm), Li(0.256ppm), Cu(0.233ppm) etcs from Curcumin component with ICP/OES, and ascertained organic components of propanoic acid(1.859), benzene(10.814), phenol(14.194) etcs from Curcumin component with GC/MSD.

Rusty Images Applied Fashion Design - For Digital Textile Printing Method - (녹 이미지를 응용한 의상디자인 - 디지털 텍스타일 프린팅 기법을 중심으로 -)

  • Yoon, Ji-Ill;Lee, Youn-Hee
    • The Research Journal of the Costume Culture
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    • v.18 no.5
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    • pp.1003-1016
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    • 2010
  • The purpose of this study is to reorganize any rusty image including natural modeling characteristic presented from the natural phenomenon to certain patterns in order to create the fashion design that are valued in the expansion of independently expressional area and modeling art. As a method for research, the author analyzed the concept and characteristic for rust with a base of theoretical background by the documental research and realistic consideration, analyzed its modeling characteristic through domestic and overseas pictures, and e-documents as data, inspected the modeling activities of various categories that various images were adapted related to rust, looked into the concept of Digital Textile Printing and its producing procedure as an expressional method, and analyzed the examples of modern dress and its ornament making use of Digital Textile Printing. The conclusions of this study are as below. First, the rust occurred due to the natural phenomenon is the bond with different material like metal, each unique modeling characteristic occurs and harmony of various patterns has abundant aesthetic value. Second, the author could endowed sensible characteristic and speciality with works and could produce creative fashion design that painting, abstractive pattern and harmony of unique sense of colors are significant by using the image of rust, Third, to emphasize natural feeling of rust, the author could develop creative design that simple silhouette and impressive pattern look significant by reorganizing and applying rust according to repetition, increment, rhythm, contract, emphasis and harmony. Fourth, Digital Textile Printing method is used to induce visual effect by the expression of feels of rust, and the author could express the natural patterns, delicate expression for the feels of a material and unique design of emotion.

Survey evaluation of thermal boundary condition in the inside and outside of double skin facade

  • Shin, Hyun-Cheol;Jang, Gun-Eik
    • KIEAE Journal
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    • v.15 no.4
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    • pp.29-35
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    • 2015
  • Purpose: Double skin facade is a representative advantageous passive technology of building skin in the aspect of energy saving and environment improvement, reduces heat loss with buffer space in winter season and enhances indoor air and comfort of residents by activating natural ventilation in mid-season. However, in summer season, temperature increase in the intermediate space due to solar energy from exterior transparent skin could be a potential problem; also, relatively weak buoyancy of air caused by low density difference between double-skin facade could increase cooling load as air of intermediate space in high temperature hangs. However, proof data is insufficient to objectify such phenomenon. Method: In this study, researchers surveyed air temperature of intermediate space and airflow and diagnosed its cause targeting on applied multistory facade in the building which gives thermal uncomfort to residents. Also, the researchers produced Solar-air heat transfer coefficient meter, measured thermal boundary condition of double-skin facade, and presented the result of measurement as an objectified verification material regarding overheating phenomenon in the intermediate space of double-skin facade in summer season. Result: Inefficient condition was verified that total heat increases and overheating due to insufficient natural ventilation in multistory facade. In addition, logic behind preceding research was objectified and verified regarding high temperature phenomenon in the intermediate space which could increase cooling load in summer season.