• Title/Summary/Keyword: degree distribution

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Distribution of Scirpus planiculmis F. Schmidt on the Ploder Land of Southwest Seashore (남서해안(南西海岸) 간척지(干拓地)에 있어서 새섬매자기(Scirpus planiculmis F. Schmidt) 의 분포(分布))

  • Lee, K.S.;Yu, S.J.;Park, S.H.;Choi, S.Y.
    • Korean Journal of Weed Science
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    • v.11 no.1
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    • pp.19-25
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    • 1991
  • This studies were conducted to get the basic information for the control of Scirpus planiculmis F. Schmidt in polder land. S. planiculmis was found to be the dorminant species all over the polder land of southwest seashore in Korea, while S. fluviatilis A. Gray was observed alone or with S. planiculmis at pond, waterway, and riverside. The degree of appearance of S. planiculmis was gradually increased with time and showed the peak at 4th and 5th year after cultivation. The density of S. planiculmis were higher in higher salinity area than in lower area. The control of S. planiculmis has been practised by herbicides and hand weeding together.

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Longitudinal Alterations of Microarchitecture and Mineralization Distribution on Trabecular Bone Due to Metastatic Bone Tumor (전이성 골암에 의한 해면골의 미세구조와 골화 분포 변화)

  • Park, Sun-Wook;Jeon, Ok-Hee;Ko, Chang-Yong;Kim, Chi-Hyun;Kim, Han-Sung;Chun, Keyoung-Jin;Lim, Do-Hyung
    • Journal of Biomedical Engineering Research
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    • v.30 no.5
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    • pp.444-451
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    • 2009
  • Purpose: The aim of present study is to detect longitudinal alterations of mechanical characteristic determined by bone quality (microarchitecture and degree of mineralization) on femur trabecular bone due to metastatic bone tumor Materials and Methods: Each 6 female SD rats (12 weeks old, approximate 250g) were allocated in SHAM and TUMOR Group. W256 (Walker carcinosarcoma 256 malignant breast cancer cell) was injected into the right femur (intraosseous injection) in TUMOR Group, whereas 0.9% NaCl (saline solution) was injected in SHAM Group. The right hind limbs of all rats were scanned by in-vivo micro-CT to acquire structural parameters, bone mineral density, X-ray attenuation and bone mineralization distribution at 0 week and 4 weeks after surgery. Results: BMD, BV/TV and Tb.N of trabecular bone in TUMOR group were markedly decreased (26%, 11% and 23%) while those in SHAM group were significantly increased (34%, 48% and 11%) (p<0.05). BS/BV, Tb.Sp and SMI in TUMOR group were significantly increased (-16%, 38% and 2%) compared with those in SHAM group (-33%, 12% and -16%) (p<0.05). Additionally, bone mineralization in TUMOR group significantly decreased while those in SHAM group was significantly increased (p<0.05). Conclusion: It is identified that how much bone microarchitecture and mineralization are diminished due to the metastatic bone tumor. The results may be helpful to prediction of fracture risk by metastatic bone tumor.

Studies on Error Propagation by Simulation Model -Main description of experments of aero-triangulation- (횡응모형에 의한 오차전파에 관한 연구 -공중삼각측량의 실험을 중심으로-)

  • 백은기
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.18 no.1
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    • pp.4021-4037
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    • 1976
  • This paper describes the actual experiments of the error propagation and studies of analytical photogrammetry using the simulation method in which we can find the causes of the errors. These studies and the results give the valuable data which are very effective for systematically controlling the errors in aerial triangulation. The main contents in my paper are as follows: 1. Dose the scale errors in the successive models in the form of normal distribution appear when the observation errors propagate in the form of normal distribution\ulcorner 2. In what form does this scale error propagation in the actual model appear\ulcorner 3. When the causes of the scale error propagation are found, is the evaluation standard determined normally\ulcorner 4. What degree of influence is there form the constant errors\ulcorner I have done several experiments using the simulation method technique to solve the complicated error propgation of aerial triangulation which is the effective means to research the relations between cause and effect. In this paper, the studies have concentrated on the following points of simulation experiments. (1) The first part descries how we can produce the soft program of the simulation experiment. (2) The second part is the method propagating the errors in the simulation models and the kinds of errors. (3) The final part is the most important; that is the analyzing and evaluation of control during actual work. From the above-mentioned points, it is said that these studies are a very important development in the field of controlling and managing aerial photogrammetry and especially in the case of error propagation, we can clearly find the causes of the errors and steps and parts of errors generated when we use these techniques.

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A New Approach to the Analysis of Multi-span Continuous Beams (다경간(多徑間) 연속(連續)보의 해석(解析)에 관한 새로운 방법(方法))

  • Yang, Chang Hyun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.1
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    • pp.85-95
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    • 1992
  • The moment distribution method has been widely used for the past sixty years for determining the end moments of structural frames. However, the method trends to show more complexity of the procedures and approximation of the results as the degree of indeterminancy increases. The previous study proposed closed form formulas for the analysis of the continuous beams up to four spans. These formulars show simpler forms and provide perfectly rigorous solution in comparision with the moment distribution method. This study proposes closed form formulas for the analysis of multi-span continuous beams which are basically similar to the equations developed in the previous study. It is shown that these formulars may also produce more rigorous results and lead to simpler calculation processes. The proposed approach may be one of the new methods for the analysis of multi-span continuous beams or the rigid frames.

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A Study on Visual Perception Characteristics of the Space of Cafe through Tracing the Observing Intention (주시의도성 추적을 통한 카페공간의 시지각특성에 관한 연구)

  • Choi, Gae-Young;Kim, Jong-Ha
    • Korean Institute of Interior Design Journal
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    • v.22 no.3
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    • pp.91-99
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    • 2013
  • It is easier to objectify the designing process with the analysis of how users perceive any space depending on the purpose of space visiting in the interactions of them and images. This study analyzed the observation characteristics perceived through observation frequency and time depending on the purpose cafe customers to understand what effect the design factors constructing the space has on the observation characteristics which are the results obtained as information through visual perception. The followings are the results of this study. First, The time range for searching or wandering and the observation characteristics could be estimated by the meaning of observation time by grade with the setup of time-range out of the distribution of sections. Second, at the time distribution by section, when there was intention, the observation time was found to have higher occupation. Third, though the higher section frequency is likely to have more observation time, the grades of II/V had higher frequency of [Intention] and the time had higher [Non-Intention], which revealed that there is a tendency for the observation characteristics vary in a large degree depending on whether there was intention or not. Fourth, by the application of the observation characteristics of each grade for interrelation analysis depending on whether there is any intention to the space of cafe, the detailed space characteristics could be compared with observation tendency. The difference of obtained information has an effect on obtaining perceived information, and since the intention may affect any information which is obtained, it is necessary for design information suitable to visit purpose or users' observation intention to be transferred in the process of designing. Analyzing the effect of any change to designing factors on the sight inducing intention and synchronization will help to understand the emotional design focused on users.

A Study on Roughness Measurement of Polished Surfaces Using Reflected Laser Beam Image (레이저빔 반사 화상을 이용한 연마면 거칠기 측정법에 관한 연구)

  • Shen, Yun-Feng;Lim, Han-Seok;Kim, Hwa-Young;Ahn , Jung-Hwan
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.2 s.95
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    • pp.145-152
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    • 1999
  • This paper presents the principle and experimental results of a non-contact surface roughness measurement by means of screen projected pattern of lase beam reflected from a polished surface. In the reflected laser beam pattern especially from a fine surface like ground or polished one, light intensity varies from the center fo the image to its boundary as the Gaussian distribution. The standard deviation of a light intensity distribution is assumed to be a good non-contact estimator for measuring the surface roughnes, because the light reflectivity is known to be well related with the surface roughness. This method doesn't need to discriminate between the specularly reflected light and the diffusely reflected one, whereas the scattered laser intensity method must do. Nor it needs to adjust the change of light intensity caused by environmental lights or specimen materials. Reflected laser beam pattern narrowly spreads out in the vertical direction to tiny scratches on the polished surface due to abrasives. The deeper the scratch the more the dispersion, which means the rougher surface. The standard deviation of the pattern is nearly in proportion to the surface roughness. Measurement errors by this method are shown to be below 10 percent compared with those obtained by a common contact method. The inclination of measuring unit from the normal axis causes the measurement errors up to 10 percent for an angle of 4 degree. Therefore the proposed method can be used as an on-the-machine quick roughness estimator within 10 percent measurement error.

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Seizure-related Encephalopathy in Rats Intoxicated with Diisopropylfluorophosphate

  • Kim, Yun-Bae;Hur, Gyeung-Haeng
    • Toxicological Research
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    • v.17 no.2
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    • pp.73-82
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    • 2001
  • The incidence and distribution of necrotic and apoptotic neural cells, and activated astrocytes in the brain of rats intoxicated intra peritoneally with diisopropylfluorophosphate were investigated. Pyridostigmine bromide (0.1 mg/kg) and atropine methylnitrate (20 mg/kg) were pretreated intramuscularly 30 min and 10 min, respectively, prior to diisopropylfluorophosphate (4-10 mg/kg) administration. Diisopropylfluorophosphate induced severe limbic seizures, early necrotic and delayed apoptotic brain injuries, and rapid astrocytic responses. The necrosis, which was closely related to seizure intensity, was observed as early as 1 hr after intoxication predominently in hippocampal pyramidal cells, cerebellar Purkinje cells and neurons in pyriform/entorhinal cortices, showing malacia of neurophils. In contrast, apoptosis started to appear 12 hr after intoxication in neurons in thalamus, amygdala and neocortex, and ephendymal cells surrounding the 4th ventricle. Since marked apoptosis was induced in rats exhibiting relatively-low seizure intensity, the degree of necrosis and apoptosis was shifted to each type of injury according to the seizure intensity. Activated astrocytes, observed within 1 hr along the limbic system, were suggested to affect the neural injury patterns by producing high level of nitric oxide. However, the distribution of activated astrocytes was not in parallel with those of necrotic or apoptotic injuries, implying that the astrocytic responses resulted from seizure activity rather than neural injuries. Furthermore, astrocytes in malacic tissues disappeared during the severe limbic seizures. Therefore, it would be one of the cautionary notes on the expression of glial fibrillary acidic protein in astrocytes as a biochemical marker of brain injuries following acute exposure to organophosphates.

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A Agricultural Development and Agricultural Regions in Egypt (이집트의 농업 발달과 농업 지역)

  • Lee, Sang-Yool
    • Journal of the Korean association of regional geographers
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    • v.10 no.2
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    • pp.479-496
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    • 2004
  • This study attempts to examine Egyptian agricultural development with regard to the social and political changes in the Egypt, and tries to explore the patterns of major crops and those spatial distribution nowadays. Also, land reclamation processes and farming activities are explained. Agricultural development in Egypt has been considerably affected by historical international trade, and those crops such as cotton and sugar cane have been especially protected and controlled as strategic crops by the Egyptian governments. The issues of land ownership have been varied with political environments by periods, but the controls to the strategic crops have been consistently maintained to a degree though some variations. since the 1990s, national liberalization programs also caused to change the agricultural policies which have affected the adjustments of crop production and land use. Spatial distribution of major crops and farming activities are examined in relation to natural environments by Delta, Middle and Upper Egypt, desert areas. The projects of land reclamation after 1952 are evaluated with the effects of government intervention, and the actors in use of the reclaimed lands are investigated.

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Image Positioning for Spa Destinations: Focusing on the Top 10 Spa Destinations in Korea (온천관광지 이미지 포지셔닝: 국내 10대 온천을 중심으로)

  • Yang, Lee-Na;Kim, Si-Joong
    • The Journal of Industrial Distribution & Business
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    • v.9 no.2
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    • pp.39-45
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    • 2018
  • Purpose - The purpose of this study is to examine the image similarity and attribute recognition of the top 10 rated spa destinations (Chungnam Deoksan, Chungnam Dogo, Busan Dongrae, Daejeon Yuseong, Chungnam Asan, Gyeongbuk Bomun, Chungbuk Suanbo, Gyeongnam Jangyu, Chungnam Onyang, & Gyeongbol Bugok) in Korea based on the visits to these spa places by the customers. Research design, data, and methodology - The survey of this study was conducted on the visitors to the top 10 spa destinations in Korea from April 8 ~ April 21, 2017, and a total of 300 questionnaires were distributed. Of them, effective questionnaires used in the final study were a total of 241. In this study, empirical analysis was made through frequency analysis, factor analysis, and multidimensional scaling ALSCAL(spinning symmetry for image similarity and rectangle for attributes recognition) by using the Statistics Package SPSS 24.0. Results - According to the analysis result of spa destination image similarity, the stress level was 0.16453 and the level of the stress was good. Moreover, the coefficient of determination (RSQ) was, which had a description of each aspect of the spa destination, 0.79908. According to the results of attribute recognition, the stress value of 0.11805 represents a degree of conformity, and the coefficient of determination(RSQ) appeared at 0.98665. Therefore, the results of this analysis are that the similarities between spa destinations and the attribute recognition of the spa destinations is a suitable model that is properly expressed in two dimensions. Conclusions - First, according to the analysis result of image similarity, Deoksan & Dogo spa revealed similar images, as well as the Dongrae and Yuseong spa, while on the contrary Asan, Bomun, Suanbo spa has different images from the rest. Second, according to the results of attribute recognition, Asan and Onyang spa has competitiveness in terms of accessibility to spa destination; Yuseong, Dongrae, Jangyu spa in terms of spa facilities, spa tourism conditions, and service & shopping conditions. while spa water quality and spa costs showed low attribute reflection for all 10 spas. Therefore, the spa visitors cannot recognize the differentiation of spa water quality and spa costs.

Economical Ventilation Effectiveness to Reduce Hazardous Chemical Emissions for a Nail-Salon Worker

  • KWON, Woo-Taeg;JUNG, Min-Jae;LEE, Woo-Sik;KWON, Lee-Seung;SO, Young-Jin
    • Journal of Distribution Science
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    • v.17 no.7
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    • pp.65-76
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    • 2019
  • Purpose - The purpose of this study is to investigate economical ventilation effectiveness to reduce hazardous materials exposure and damage of workers by analyzing exposure amount of noxious substances under various ventilation conditions of nail salon for indoor environments. Research design, data, and methodology - This study was carried out with cooperation of Nail shop located in SeongNam city to involve an analysis of the environmental impact indoor air quality, pollutant exposure and economical cost-effectiveness in the nail workplace. The hazardous substances were PM-10(Particulate Matter-10㎛), VOCs(Volatile Organic Compounds) and Formaldehyde, which are the major materials of nail workplace. Results - PM-10 is reduced by about 60% with air cleaner, forced artificial ventilation by 32%, and natural ventilation by about 12%. TVOCs and Formaldehyde showed similar efficiency (80~100%) after natural ventilation and ventilation after 60 minutes. The removal efficiencies of VOCs and formaldehyde were similar to those of natural ventilation and mechanical ventilation system. However, in case of dust, natural ventilation was reduced by artificial ventilation system due to inflow of external dust during natural ventilation. Conclusions - If the pollution degree of outdoor air is not high, air volume is high, and natural ventilation is performed when the air conditioning and heating system is not operated. Even at the end of the work, it keeps operating for 60 minutes to remove the pollutants generated. Results of this analysis demonstrated that the worker environment can be improved by adopting institutional legislation and guidelines for ventilation.