• Journal of Forest and Environmental Science
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• v.18 no.1
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• pp.45-52
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• 2001

This paper investigated external factors (height. crown width. diameter breath height, clear length) of tree and electric resistance ($k{\Omega}$) in damaged forest by Thecodiplosis japonensis Uchida et Inouye. The height. crown width and diameter breath height of tree external factors have high a coefficient of correlation. but clear length has not a coefficient of correlation. In relationship of electric resistance and external factor. big tree that height. crown width. diameter breath height has lower electric resistance value than that of small tree. (low electric resistance value is high tree vigor, high electric resistance value is low tree vigor)) Dead tree have smaller diameter breath height. crown width. higher clear length than survival tree in damaged forest by Thecodiplosis japonensis Uchida et Inouye. To investigation of relationship external factors according to electric resistance value. electric resistance value was divided three class (< $l4k{\Omega}$, possible of survival. $14{\sim}20k{\Omega}$, > $20k{\Omega}$, possible of dead). In lower class(< $l4k{\Omega}$), external factors have bigger which was height. crown width. diameter breath height and lower which was clear length than them of higher class ($14{\sim}20k{\Omega}$, > $20k{\Omega}$). Linear regression solutions of electric resistance and external factors were Y = -0.572 ${\times}$ Height - 1.163 ${\times}$ crown width - 0.242 ${\times}$ diameter breath height + 0.757 ${\times}$ clear length + 25.765. Regression solutions were significant in 5%.

• Journal of radiological science and technology
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• v.39 no.4
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• pp.565-570
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• 2016

Radioactive iodine($^{131}I$) treatment reduces recurrence and increases survival in patients with differentiated thyroid cancer. However, it is important in terms of radiation safety management to measure the radiation dose rate generated from the patient because the radiation emitted from the patient may cause the exposure. Research methods, it measured radiation dose-rate according to the elapsed time from 1 m from the upper abdomen of the patient by intake of radioactive iodine. Directly comparing the changes over time, high dose rate sensitivity and efficiency is statistically significant, and higher chamber than GM counter(p<0.05). Low dose rate sensitivity and efficiency in the chamber had lower levels than gm counter, but not statistically significant(p>0.05). In this study confirmed the characteristics of calibrated ionization chamber and GM counter according to the radiation intensity during high-dose radioactive iodine therapy by measuring the accurate and rapid radiation dose rate to the patient explains, discharged patients will be reduced to worry about radiation hazard of family and others person.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.2
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• pp.164-170
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• 2005

The amounts and nutrient compositions in precipitation, throughfall, stemflow and soil solution of natural deciduous forests (Quercus variabilis and Q. mongolica) were examined in Gwangju, Gyeonggi Province. The proportion to gross precipitation was $85\%$ for throughfall, $2-6\%$ for stem flow, $53-54\%$ for Ao horizon soil solution, $23-30\%$ for A horizon soil solution, and $11-14\%$$ for B horizon soil solution, respectively. pH and K concentration increased in throughfall and only K concentration increased in stemflow. Canopy leaching appeared to influence these changes. pH, and Ca and Mg concentrations increased significantly in the Ao horizon soil solution, and Ca concentration was higher in the B horizon than in the A horizon. However, there were no significant differences in pH and other nutrient concentrations between A and B horizons. Litter decomposition and leaching from Ao horizon might explain the changes. K, Mg and Cl concentrations in throughfall and soil solution decreased with precipitation. Nutrient contents increased in the transports from precipitation, through throughfall, to Ao horizon soil solution, while they decreased in the transport from A to B horizon soil solution. Stemflow contained less than $10\%$ of total (throughfall plus stemflow) nutrient contents.

• Journal of Korean Society of Forest Science
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• v.102 no.2
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• pp.247-254
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• 2013

The objective of this study was to assess the canopy fuel characteristics of five major coniferous species in Korea. This study was also developed allometric equations for the canopy fuel load and canopy base height of the major coniferous species using the allomeric equations of biomass developed by the Korea Forest Research Institute and the data from the $5^{th}$ National Forest Inventory. Among the major coniferous fuel types, Pinus koraiensis stands had the highest mean canopy bulk density, 0.34 kg/$m^3$, followed by Gangwon region Pinus densiflora stands 0.28 kg/$m^3$, Pinus thunbergii stands 0.24 kg/$m^3$, Pinus rigida stands 0.15 kg/$m^3$, Central region Pinus densiflora stands 0.12 kg/$m^3$ and Larix leptolepis stands 0.09 kg/$m^3$. The adjusted multiple coefficient of determination of the developed models ranged from 0.6321 to 0.9950 for canopy fuel load and 0.6390 to 0.8539 for canopy base height.

• Korean Journal of Environment and Ecology
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• v.35 no.4
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• pp.398-407
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• 2021

This study intended to identify causes of poor tree vigor in the Hanbando coastal forest by investigating its geographical environment, climate condition, soil physicochemical characteristics, and growth condition of Pinus thunbergii. It divided the forest into an area with poor tree vigor or dead standing trees and a control area with good tree vigor and examined them separately. The survey showed that stand density was significantly higher in the area with poor tree vigor. In contrast, the crown width in the area with good tree vigor was wider. The number of dead standing trees and the stand density showed a negative correlation. The stand density and diameter at breast height (DBH), tree height, crown height, and crown width also showed a negative correlation. The result indicated that, as the tree's stand density increases, the crowns of individual trees overlapped and the lower branches died. Then crown height and crown width decreased, and the number of leaves and photosynthesis was reduced, leading to lower tree height and weaker growth of breast diameter. As a result, tree vigor weakened, and combined with environmental pressures from the lack of moisture and nutrients in coastal soil and salty wind, P. thunbergii in coastal areas is expected to die massively. Although the causes of dead standing trees and poor tree vigor of P. thunbergii in the Hanbando coastal forest are complicated, poor management of adequate tree density in response to the growth of P. thunbergii is the primary cause. The secondary cause is external environmental pressures, including unfavorable soil conditions and salty and strong wind that obstruct the growth of P. thunbergii.

• ETRI Journal
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• v.8 no.1
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• pp.34-43
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• 1986

에너지 관리 시스팀(Energy Management System)의 한 분야로서 보일러 제어를 들수 있는데, 보일러의 경우에 있어서 보일러 부하에 따른 연료의 연소 처리 제어, 압력차의 제어, 급수 제어 장치, 점화 등에 자동 제어가 적용되어 실질적인 보일러의 안전 운전 및 열효율을 개선시킬수 있다. 본고는 (주) 열연 보일러의 수관식 관류 보일러에 마이크로프로세서를 이용하여, 급수, 연소 제어를 구현한 내용이다.

• 공원문화
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• s.66
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• pp.58-59
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• 1997

• 농업기술회보
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• v.41 no.1 s.485
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• pp.21-23
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• 2004

• Monthly Duck's Village
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• s.79
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• pp.96-97
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• 2010

• 프린팅코리아
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• s.5
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• pp.178-181
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• 2002