• Title/Summary/Keyword: the influence of wind

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A Research on The Pulse & Disease-patterns and Diagnostic Theory of Exogenous Febrile Disease in the "Sanghanjeonsaengjip(傷寒全生集)" ("상한전생집(傷寒全生集).변상한발열례(辨傷寒發熱例)" 등에 대한 연구(硏究))

  • Choi, Dong-Su;Sheen, Yeong-Il1
    • Journal of Korean Medical classics
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    • v.23 no.4
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    • pp.103-153
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    • 2010
  • "Sanghanjeonsaengjip(傷寒全生集)" is a classic medical work, written by the outstanding physician Dohwa(陶華) in the Ming Dynasty. The characteristic of "SangHanJeonSaengJip" is that this book succeeded to the spirit of pattern identification and treatment of Treatise on Cold Damage Diseases, newly changed a table of contents by symptoms, and together with this indicated the prescriptions in accordance with diswase-pattern at "YujeunghwalInseo(類證活人書)", "Hwajegookbang(和劑局方)" etc. Also because this kept the existing ephedra decoction, cinnamom twig decoction, minor decoction of bupleurum, decoction for reinforcing middle-energizer and replenishing qi etc.'s name on and unlikely indicated the medicine composition, it caused confusion, but at the later ages "Euhakipmun(醫學入門)" the so-called 'Doci(陶氏)' was added to the prescription name, so we are able to distinguish. Together with this, this book dose not indicate the dosage of medicine and indicates the first, the second, and the third classes[上中下] below medicine. As this dose not mean the three grades of quality"good, fair, and poor[上中下] of "Shennong's Classic of Materia Medica" but expresses the sovereign medicinal as the first class[上], minister medicinal as the second class[中] and assistant and courier medicinal as the third class[下], doctors can voluntarily decide the dosage of medicine in accordance with the degree of disease. At this thesis, I single out ten chapters in contents of 2nd volume named Hyeong(亨) corresponding to the details, among "Sanghanjeonsaengjip(傷寒全生集)". I discussed superficial fever types of exogenous febrile disease in chapter 1, aversion to cold types of exogenous febrile disease in chapter 2, syndrome caused un-sufficient sweating in chapter 3, organic fever types of exogenous febrile disease in chapter 4, aversion to wind types of exogenous febrile disease in chapter 5, Tidal fever types of exogenous febrile disease in chapter 6, Alternative attacts of chills and fever in chapter 7, Dysphoria with smothery sensation in chapter 8, Fidgetiness of exogenous febrile disease in chapter 9, and Headache of exogenous febrile disease in chapter 10, and together with this I discussed, in detail, which influence the prescriptions which are listed on each chapter have caused on future generations In accordance with this, I think that the above-mentioned symptoms and prescriptions are important when I research cold damage and warm disease study. So I orderly research revision, annotation, rendering and an investigation.

Control of the flow past a sphere in a turbulent boundary layer using O-ring

  • Okbaz, Abdulkerim;Ozgoren, Muammer;Canpolat, Cetin;Sahin, Besir;Akilli, Huseyin
    • Wind and Structures
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    • v.35 no.1
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    • pp.1-20
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    • 2022
  • This research work presents an experimental study's outcomes to reveal the impact of an O-ring on the flow control over a sphere placed in a turbulent boundary layer. The investigation is performed quantitatively and qualitatively using particle image velocimetry (PIV) and dye visualization. The sphere model having a diamater of 42.5 mm is located in a turbulent boundary layer flow over a smooth plate for gap ratios of 0≤G/D≤1.5 at Reynolds number of 5 × 103. Flow characteristics, including patterns of instantaneous vorticity, streaklines, time-averaged streamlines, velocity vectors, velocity fluctuations, Reynolds stress correlations, and turbulence kinetic energy (), are compared and discussed for a naked sphere and spheres having O-rings. The boundary layer velocity gradient and proximity of the sphere to the flat plate profoundly influence the flow dynamics. At proximity ratios of G/D=0.1 and 0.25, a wall jet is formed between lower side of the sphere and flat plate, and velocity fluctuations increase in regions close to the wall. At G/D=0.25, the jet flow also induces local flow separations on the flat plate. At higher proximity ratios, the velocity gradient of the boundary layer causes asymmetries in the mean flow characteristics and turbulence values in the wake region. It is observed that the O-ring with various placement angles (𝜃) on the sphere has a considerable alteration in the flow structure and turbulence statistics on the wake. At lower placement angles, where the O-ring is closer to the forward stagnation point of the sphere, the flow control performance of the O-ring is limited; however, its impact on the flow separation becomes pronounced as it is moved away from the forward stagnation point. At G/D=1.50 for O-ring diameters of 4.7 (2 mm) and 7 (3 mm) percent of the sphere diameter, the -ring exhibits remarkable flow control at 𝜃=50° and 𝜃=55° before laminar flow separation occurrence on the sphere surface, respectively. This conclusion is yielded from narrowed wakes and reductions in turbulence statistics compared to the naked sphere model. The O-ring with a diameter of 3 mm and placement angle of 50° exhibits the most effective flow control. It decreases, in sequence, streamwise velocity fluctuations and length of wake recovery region by 45% and 40%, respectively, which can be evaluated as source of decrement in drag force.

Effects of Environmental Factors on the Stability and Vegetation Survival in Cutting Slope of Forest Roads (임도 절토 비탈면의 안정과 식생활착에 미치는 환경인자의 영향)

  • Jung, Won-Ok
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.2
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    • pp.74-83
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    • 2001
  • The purpose of this study was investigate to the influence of forest roads characteristics and environment factors on the soil erosion, stability and vegetation survival of cut slope in forest roads. The results obtained could be summarized as follows; 1. The correlated factors between slope erosion and variables in cut slope were altitude, convex, degree of slope, length of slope and soil depth. In the stepwise regression analysis, length of slope and soil hardness was a high significant and its regression equation was given by -89.6136 + 15.0667X14 + 16.6713X15($R^2$ = 0.6712). 2. The main factors influencing the stability of cut slope were significant in order of coverage, middle, convex, length of slope and north, and its discriminant equation was given by -1.019 + 0.064X22 - 0.808X8 - 0.622X24 + 0.742X11 - 0.172X14 - 0.545X6 ($R^2$ = 0.793). 3. The centroids value of discriminant function in the stability and unstability estimated to 1.244 and -1.348, respectively. The boundary value between two groups related to slope stability was -0.1038. The prediction rate of discriminant function for stability evaluation of was as high as 91.3%. 4. The dominant species of invasion vegetation on the cut slope consist with Carex humilis, Agropyron tsukushiense var. transiens, Calamagrostis arundinacea, Miscanthus sinensis var. purpurascens, and Ixeris dentata in survey area. The rate of vegetation invasion more increased by time passed. 5. The life form of invasion vegetation in cut slop showed to $H-D_1-R_{2,3}-e$ type of the hemicryptophyte of dormancy form, dissem inated widely by wind and water of dissminule type, moderate extent and narrowest extent of radicoid type, erect form of growth form. 6. The correlated factors between forest enviroment and coverage appeared north, passage years and middle position of slope at 5% level. The forest environment factors influencing the invasion plants in survey area were shown in order to altitude, passage years, rock(none), forest type(mixed) and stone amount. The regression equation was given by 17.5228 - 0.0911X3 + 3.6189X28 15.8493X22 19.8544X25 + 0.3558X26 ($R^2$ = 0.4026).

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A Historical Drama about Mathematics and Mathematicians of the Joseon Dynasty (조선 시대 수학과 수학자에 대한 역사 드라마)

  • Lee, Kyung-Eon
    • The Journal of the Korea Contents Association
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    • v.14 no.7
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    • pp.93-102
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    • 2014
  • Recently, various types of dramas have been broadcasted in Korea. Especially, historical dramas having backgrounds about historical events or characters have been recorded high ratings of the viewing audience, as well as a lot of influence on many parts of Korean society. Besides, the historical drama like raised a craze for popular Korean cultures in many Asian countries. The subjects and characters of historical drama are diversifying in recent years. For example, is a royal cook, is a story about running away slaves and their chaser, is a story about a very well-known painter of the Joseon Dynasty era, and is a veterinarian. At this point, in celebration of the officially appointed "year of mathematics", it is very meaningful to demonstrate the importance of mathematics with a historical drama about mathematics and mathematicians of the Joseon Dynasty. In this article, the reasons for production of historical dramas about mathematics and mathematicians in the Joseon Dynasty was presented in two ways. First, modern mathematics has high level of abstractness as its nature, and therefore many students and the public can not understand what except for some areas. Second, it is possible the easier and various approaches can be used to deal with contents about real-life in the view of popularization of mathematics. Also, this article would aim to explore the main character and episodes about mathematics and mathematicians in Joseon Dynasty. For example, the anecdote of Hong Jung Ha, the works of mathematics in the King Sejong's periods, the study of Hong Gil Ju, the joint researches between Nam Byung Gil and Lee Sang Hyuk, the story of Lee Seung Hun, and the mathematics study of middle class people.

A Study on the Fire Spread Risk of Resident Buildings With Pilotis (필로티 건물 이격거리에 따른 화재확산 위험성 연구)

  • Choi, Seung-Bok;Choi, Doo-Chan;Choi, Don-Mook
    • Fire Science and Engineering
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    • v.31 no.4
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    • pp.103-110
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    • 2017
  • With the common tendency in the accordance with the trend, low-stories built edifices that are Pilotis-oriented structured exponentially and constantly increasing its number of buildings. It inevitably contains its risks of facing conflagrations as most of its part is used as parking lots. In the parking lots, the length of the flame has a heavy-weighted possibility that it would get increased because the heat release rate gets relatively high due to the vehicle insulation. Following on top of that, due to the nature of the Pilotisconsisting of pillars, there is a risk of flame spread to the adjacent building if the same Pilotis-structured buildings are adjacent to each other, if the flame spreads to the surroundings due to the influence of the wind. Because the most of the pilotis-structured-buildings have this entrance that makes the residents be able to enter, if the entrance were plugged the resident get a serious risk of a poisonous gas and a flame. Therefore, if the parking-lots of the pilotis-structured-buildings are adjacent to each other it requires a space to prevent the place from the spread of flame. This research studied how far is appropriate to prevent flame spreading with FDS. As a result, the study found that the distance at least 3.0 m is required.

Analysis of the Influence of Street Trees on Human Thermal Sensation in Summer (여름철 인간 열환경지수에 미치는 가로수의 영향 분석)

  • Jo, Sang-man;Hyun, Cheol-ji;Park, Soo-kuk
    • Journal of the Korean Institute of Landscape Architecture
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    • v.45 no.5
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    • pp.105-112
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    • 2017
  • In order to analyze the effect of street trees on human thermal sensation(thermal comfort) in summer, microclimatic data were measured and analyzed at sunny and shaded locations of two deciduous broadleaf and three broadleaf evergreen species of street trees. As a result, the mean differences by species in air temperature, relative humidity and wind speed were small: $0.2{\sim}1.5^{\circ}C$, 0.9~5.3% and $0.1{\sim}0.5 ms^{-1}$, respectively, but the mean difference in the mean radiant temperature was great, $27.1^{\circ}C$. In the results of physiological equivalent temperature(PET) and universal thermal climate index(UTCI), which are human thermal sensation(thermal comfort) indexes, the shaded locations by the trees showed mean reduction rates of 21.2~31.3% in the PET compared with the sunny location, which are equivalent to 1.5~2.5 levels of thermal perception. Also, 12.7~20.0% in the UTCI was reduced by the trees' shadows, which is equivalent to 1~1.5 levels of heat stress. In addition, although the broadleaf evergreen trees had 5% greater mean reduction in PET than that of the deciduous broadleaf trees, the Zelkova serrata that belonged to the deciduous broadleaf trees showed the equivalent thermal reduction effect as the broadleaf evergreen trees because of the high density of branches and leaves. Therefore, the mean radiant temperature and the density of the crown(branches and leaves) were the main influences in thermal modification by these street trees in summer.

Study on the Operation Characteristics of Heat Detectors through Fire and Wind Tunnel Experiment (풍동실험과 화재실험을 통한 열감지기의 동작특성에 관한 연구)

  • Ryu, Hocheol;Kim, Doohyun
    • Journal of the Society of Disaster Information
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    • v.11 no.2
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    • pp.203-209
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    • 2015
  • The heat detector detects heat in the fire and is an important core element of the automatic fire alarm system used generally for every fire prevention objects. The heat detector is distinguished in spot type and spread type and in spot type, there are differential and thermistor types. These heat detectors give a great influence on the loss of people and property according to the sensitivity of response such as operation time and operation temperature in actual fire and in overseas people apply it for the development of products that can be operated in the early stage of fire including certification, quality management, and comparison standard by introducing response time index through the theory of heat balance that considers the heat loss and ventilation tests. In Korea, the response time index is introduced and used in the head of sprinkler products, but it is not applied to the heat detector at present. It is necessary to introduce the response time index that shows the sensitivity of response of the heat detector the installation standard for the heat detector that the response time index is applied should be different according to the fire weight, danger degree of fire, and shape of buildings. Through this study, it tries to help reduce lives and property of people through the swift warning by installing detectors suitable for the building structure.

Meteorological and Climatic Characteristics for Improving Quality of Cultivation of Aronia in the Danyang area (단양지역 아로니아 재배 품질 향상을 위한 기상 및 기후학적 특성)

  • Moon, Yun Seob;Kang, Woo Kyeong;Jung, Okjin;Kim, Sun Mee;Kim, Da Bin
    • Journal of the Korean earth science society
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    • v.38 no.7
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    • pp.481-495
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    • 2017
  • The purpose of this study is to investigate and analyze the relationship between meteorologicalclimatic factors and fruit property data from Aronia sampling points during May to August 2016 in the Danyang area. For this purpose, we investigated the meteorological factor, the physicalchemical property of fruit and soil, and the property change of fruit according to the setting of rain and daylight shielding from Aronia sampling points. The result indicate that first, meteorologicalclimatic factors such as the maximum air temperature, the accumulated precipitation, the relative humidity, and daylight hours are a positive influence on products and maintenance of quality of Aronia as well as a suitable field for cultivating Aronia in the Danyang. However, a strong wind in April and May deeply affects the falling phenomenon of the flowering and blooming season. Second, the quality and products of Aronia show the high correlation coefficients of more than 0.9 with agricultural meteorologicalclimatic factors such as daily maximum temperature, daily soil temp, daily soil pH, cumulated precipitation, and daily soil humidity. Also, they can be predicted by the regression equations using these factors. Third, it is necessary to maintain the rain shielding in these fields because antocyanin and saccharinity components within Aronia decreased in case of heavy rainfalls. And, the result of regression analysis saccharinity and antocyanin within aronia from normal fields and rain shieldingfields at Aronia sampling points show a high correlation, respectively.

A Study on the Sea Areas Dynamic Stability of LL-26(M) Light Buoy (LL-26(M) 등부표의 해역별 동적안정성에 관한 연구)

  • Moon, Beom-Sik;Gug, Seung-Gi;Kim, Tae-Goun
    • Journal of Navigation and Port Research
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    • v.44 no.3
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    • pp.166-173
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    • 2020
  • AtoN Accident causes navigation dangerous to ships and reduces the credibility of aids to navigation. The most light buoys on the sea have the highest accident rate from the influence of sea weather such as wind, current, and waves. However, in Korea, despite the different sea weather conditions in each sea area, in calculating the dynamic stability of the light buoy, there is a problem that only limit value conditions are applied to all sea areas. Thus, the purpose of this study was to analyze the dynamic stability of the LL-26(M) light buoy, the most installed buoy of its kind on the sea and suggest a stable operation plan for the LL-26(M) light buoy. To achieve this, after analyzing the weather for each sea area of the previous study related to the light buoy, the dynamic stability (inclination angle) was estimated by applying to the representative light buoys of each sea area wherein the number of accidents caused by sea weather was high. As a result of this study, the inclination angle of LL-26(M) light buoy for each sea area was different. That is, the inclination angle caused by winds was 10.329°-36.868°, the inclination angle caused by currents was 0.123°-18.834° and the inclination angle caused by waves was 4.777°-20.695°. The results of study can be used as basic data useful for installation standards for each sea area for stable operation of the LL-26(M) light buoy.

Estimation of Reduction Rate of Airborne Chlorides base on Coastal Distance and Facilities in Incheon Port, South Korea (인천항의 대기 중 비래염분량의 시설물별 특성 및 해안거리에 따른 감소량 추정)

  • Jahe Jung;Jong-Suk Lee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.27 no.6
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    • pp.13-21
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    • 2023
  • In this study, the coastal airborne chlorides were investigated in the Incheon Port, South Korea. Monthly measurements of coastal airborne chlorides were taken for a total of 2 years from September 2021 to August 2023 at 15 locations in North, South, and New Port. We analyzed the distribution characteristics of airborne chloride based on port facilities and measurement environments, as well as the reduction characteristics of the airborne chloride with respect to coastal distance. As a result, the monthly distribution range of the airborne chloride in the North, South, and New Port varied similarly, ranging from 0.4 to 3.3 mdd. Due to the influence of seasonal winds considering the direction of the coastline, both the North Port and South Port had higher the airborne chloride in winter, while the New Port had higher content in summer. The airborne chlorides were higher at locations inside an inland sea compared to those outside an inland sea. This is because the wind coming from the sea passed through the inland sea. Even in the same region with identical coastal distances, there were variations in airborne chloride levels depending on the height above the ground. In tidal zone, the monthly airborne chlorides were significantly higher in the lower part than in the upper part. The rate of decrease equation of airborne chlorides for each port based on the distance from the coastline was derived, and the results showed that as the distance from the coastline increased, the rate of decrease in airborne chlorides was the highest for New Port and the lowest for South Port.