• Journal of Forest and Environmental Science
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• 제33권1호
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• pp.74-77
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• 2017

The purpose of this study is to analyze the effect of thinning intensity on the growth of large diameter trees in Korean white pine (Pinus koraiensis S. et Z.) plantation. Eight thinning plots were analyzed by categorizing into heavy thinning, light thinning, no thinning (control) according to thinning intensity. As a result, average DBH increased more in heavy thinning plots than in light thinning or unthinned plots. The number of large trees (DBH>25 cm) were obviously shown the most in heavy thinning plots. It is considered that heavy thinning is needed for the production of the large diameter trees.

• 한국농공학회지
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• 제31권4호
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• pp.72-80
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• 1989

Various analyses were made to investigate the stochastic structure of the daily rainfall in Korea. Records of daily rainfall amounts from 1951 to 1984 at Chinju Metesrological Station were used for this study. Obtained results are as follows : 1. Time series of the daily rainfall at Chinju were positively, serially correlated for the lag as large as one day. 2. Rainfall events, defined as a sequence of consecutive wet days separated by one or more dry days, showed a seasonal variation in the occurrence frequency. 3. The marginal distribution of event characteristics of each month showed significant dif- ferences each other. Events occurred in summer had longer duration and higher magnitude with higher intensity than those of events occurred in winter. 4. There were significant positive correlations among four event characteristics ; dura- tion, magnitude, average intensity, and maximum intensity. 5. Correlations among the daily rainfall amounts within an event were not significant in general. 6. There were no consistant significancy in identity or difference between the distribu- tions of daily rainfall amounts for different days within events. 7. Above mentioned characteristics of daily rainfall time series must be considered in building a stochastic model of daily rainfall.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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• pp.1568-1571
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• 2005

We have evaluated thermal stability of a $BaAl_2Si_2O_8:Eu^{2+}$ $(BAS:Eu^{2+})$, which have polymorph property such as hexagonal, monoclinic structure depending upon firing temperature. When both polymorph $BAS:Eu^{2+}$ were baked in air at 500 $^{\circ}C$ for 30 min, the photoluminescence (PL) intensity of $monoclinic-BAS:Eu^{2+}$ was maintained of the initial intensity. However, the PL intensity of $hexagonal-BAS:Eu^{2+}$ decreased significantly, corresponding to about 34 %. From analyses of Rietveld refinement, the difference of thermal stability of both $BAS:Eu^{2+}$ can be ascribed to both crystal structure of host materials and the average interatomic distances between $Eu^{2+}$ ion and oxygen their crystal structure which plays a key role of shield for Eu2+ ions against oxidation atmosphere.

• 전기학회논문지
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• 제61권5호
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• pp.763-769
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• 2012

For mist sensing, temperature-humidity sensor is attached on six positions of front glass and rearview mirror in automobile. Bottom-left side of front glass is the best position where mist is sensing. For mist removal, air conditioner is turned on intensity 1, 3 and is set the temperature at 17[$^{\circ}C$], 25[$^{\circ}C$]. And heater is turned on intensity 1, 3 and is set the temperature at 25[$^{\circ}C$], 32[$^{\circ}C$]. The best condition which mist is removed is temperature at 17[$^{\circ}C$] and intensity 3 of air conditioner mode. At this condition, total average value of humidity output voltage difference is 0.561[V]. Also, air conditioner mode is effective than heater mode for mist sensing and removal.

• 자원리싸이클링
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• 제13권6호
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• pp.16-25
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• 2004

인듐 성분을 포함하는 원료용액을 분무열분해 시켜서 평균 입자크기 100 nm 이하의 인듐 산화물 나노 분말을 제조하였으며, 용액의 농도, nozzle tip 크기 및 공기의 유입속도 변화에 따른 생성된 분말들의 특성 변화를 파악하였다. 본 연구는 폐 ITO로부터 나노 크기의 ITO 분말을 제조하기 위한 전 단계 연구로 수행되었다. 원료용액 내의 인듐 성분의 농도가 40 g/l로부터 350 g/l로 증가됨에 따라 생성된 분말의 평균 입자크기는 20~30 nm로부터 50~60 nm로 점점 증가하는 반면 입도분포는 더욱 불균일하게 나타나고 있었으며, XRD peak의 강도는 점점 증가하고 비표면적은 감소되었다. Nozzle tip의 크기가 1 mm로부터 5 mm로 증가함에 따라 분말들의 평균 입자크기는 40 nm 정도로부터 100 nm 정도까지 점점 증가하고 입도분포는 더욱 불균일하게 나타나고 있었으며, XRD peak 강도는 증가하는 반면 비표면적은 감소되었다. 반응로 내로 유입되는 공기의 압력이 0.1 kg/cm$^2$로부터 0.5 kg/cm$^2$로 증가되는 경우, 분말의 평균 입자크기는 90~100 nm로 현저한 변화를 나타내지 않았다. 반면 공기압력이 1 kg/cm$^2$ 및 3 kg/cm$^2$로 증가하는 경우에는 평균 입자크기가 50~60 nm 정도까지 감소하였으며, XRD peak 강도는 감소하고 비표면적은 증가되었다.

• 대한기계학회논문집A
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• 제22권4호
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• pp.953-959
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• 1998

To investigate accuracy of intensity method for measurement of the fiber orientation distribution, fiber orientation function is calculated by drawing simulation figures for the fiber orientation as varying fiber aspect ratio, fiber area ratio, and fiber orientation state, respectively. The values of fiber orientation function measured by intensity method are compared with the calculated values of fiber orientation function. The results show that measurement accuracy of the fiber orientation angle distribution by intensity method is affected by the fiber aspect ratio when the total length of oriented fiber is same. The average gradient of fiber orientation function is 0.94 for 1000mm of the total fiber length and is 0.93 for 2000 mm when the fiber aspect ratio is over 50. Measurement accuracy by intensity method is about 94% and the reliable data can be obtained by intensity method.

• 한국유기농업학회지
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• 제19권1호
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• pp.23-38
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• 2011

● The current world is suffering abnormal climate caused by global warming. The main cause of global warming is greenhouse gas such as carbon dioxide. The carbon labeling system and carbon traceability system being pushed ahead in the agricultural sector is the policy for responding to climate change to reduce greenhouse gas emissions. To make this policy more effective and enhanced, the amount of carbon emissions should be calculated based on the kind of crops or the various businesses in the agricultural sector. Therefore, in order to estimate the accurate amount of carbon emissions, it is necessary to establish carbon dioxide emission intensity of various agricultural materials added onto the agriculture, and to calculate the amount of carbon dioxide emission for each crop according to agricultural production. The purpose of this study is to establish the amount of emission, emission per agricultural materials, of agricultural materials being added for crop production as a basic step, and emission intensity which can be used in the future market in order to estimate accurate amount of carbon emission in all the policies being promoted in the agricultural sector. Therefore, in this study, in order to build LCI D/B about organic fertilizers among many organic materials added onto the organic agriculture sector, one leading company in organic fertilizer production was selected and LCA was conducted for this leading company. We had to build the intensity and integrated average concept of intensity upon the two cases once production farmers for their own consumption and farms besides organic fertilizer company were categorized even if it's little amount. But in this study, individually produced organic fertilizers were excluded. Calculated results are following. Carbon emission of mixed expeller cake fertilizer in organic fertilizer was 1,106,966.89kg-$CO^2$ and emission intensity was 0.01606kg-$CO^2$, respectively. Total emission of mixed organic fertilizers was 241,523.2kg-$CO^2$ and emission intensity was 0.01705kg-$CO^2$. And total emission of organic compound fertilizers was 94,592.66kg-$CO^2$ and emission intensity was 0.01769kg-$CO^2$, respectively.

• Imaging Science in Dentistry
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• 제31권2호
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• pp.93-99
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• 2001

Purpose: To analyze the possible association between magnetic resonance imaging signal intensity of temporomandibular joint disk and posterior attachment, and the type and extent of disk displacement, disk configuration, effusion and clinical signs in patients with internal derangement. Materials and Methods: Magnetic resonance images of the 132 temporomandibular joints of 66 patients with temporomandibular joint displacement were analyzed. The clinical findings were obtained by retrospective review of the patients' records. The type and extent of disk displacement, disk configuration and effusion were evaluated on the proton density MR images. The signal intensity from the anterior band, posterior band and posterior attachment were measured on MR images. The associations between the type and extent of disk displacement, disk configuration, effusion and clinical signs and the MR signal intensity of disk and posterior attachment were statistically analyzed by student's t-test. Results: Of 132 joints, 87 (65.9%) showed anterior disk displacement with reduction (ADR) and 45 (34.1%) showed anterior disk displacement without reduction (ADnR). The signals from posterior attachments were lower in joints with ADnR than those of ADR (p<0.05). The results showed statistically significant (p<0.05) association between the type and extent of disk displacement and disk configuration, and decreased signal intensity of posterior attachment. There were no statistical associations between pain, noise and limited mouth opening, and signal intensity of disk and posterior attachment. Conclusions: The average signal from posterior attachment was lower in joints with ADnR than that of ADR. The type and extent of disk displacement and disk configuration appeared to be correlated with the signal intensity from posterior attachment.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.702-707
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• 2001

The characteristics of flow in dividing regions are precise, therefore their classification is very important not only in industry but also in hydrodynamics. By now, many studies of flow in dividing regions have been performed, but flow characteristics that use visualization in dividing regions have not been studied. The present study of the PIV and the CFD exhibit average velocity distributions, kinetic energy distributions and total pressure distributions etc of the total flow field due to the development of the accurate visualization optical laser and of optical equipment. Also, PIV is accurate with the flows characteristics of the dividing region as continuous analysis is done using input equipment. The study analyzes average velocity vector field, average kinetic energy, x-axis stress distributions, average and total pressure distributions of dividing regions with flow for visualization of the PIV and the CFD measurement in a dividing rectangular duct.

• Journal of information and communication convergence engineering
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• 제9권5호
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• pp.487-490
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• 2011

This paper presents splitting and merging algorithm based on adaptive thresholding. The algorithm first divides the image into blocks, and then compares each block using the calculated thresholding value. The blocks which are same are merged using the certain threshold value and different blocks are split unless it satisfies the threshold value. When the block has been merged, maximum and minimum block sizes are determined then the average block size is determined. After the average block size is determined the average intensity and standard deviation of average block is calculated. The process of thresholding is applied to binarize the image. Finally, the experimental results show that the proposed method distinguishes clearly the background with text in the document image.