• Journal of Forest and Environmental Science
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• 제24권3호
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• pp.165-169
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• 2008

This study attempts to analyze the relationship between forest volume and age based on 5th NFI data and spectral characteristics of satellite imagery using ASTER sensor in Korea. Forest stand volume and age had the negative correlation with the spectral reflectance in all of the band (Blue, Green, Red, SWIR). With increasing of stand volume and age, spectral reflectance decrease. The spectral reflectance of band1 showed the highest correlation between stand volume and spectral reflectance among the VNIR wavelength. The spectral reflectance band 1, 2 (visible wavelength) and stand age have high correlation compared to other bands. The correlation coefficients between forest volume and vegetation indices have low relationship. This result indicates that the reflectance of blue band may be important factor to improve the potential of optical remote sensing data to estimate forest volume and age.

• 한국실내디자인학회논문집
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• 제15권6호
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• pp.139-149
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• 2006

Because of economic growth and the social trend to respect individuality, people's average commodity volume tends to increase. It makes people perceive the importance of storage space. The storage planning without consideration of commodity volume in the apartment can not satisfy the needs of residents. This study is developed focused on the $85m^2$ apartment which is the most representative and general type. The objectives of the study are to investigate the storage-capacity of $85m^2$ apartment offered by 4 construction companies to know the present storage condition, to investigate the average volumes and type of commodities in 30 families located in Seoul and Kyungkido to produce the necessary storage-capacity, and lastly to produce optimal storage-capacity and proportion of optimal storage-capacity considering the volume of the furniture owned by each resident. The results of the study are 1) the storage capacity for commodity volume in $85m^2$ apartment is $19.41m^3$. 2) the optimal storage-capacity which only counts the storage volume of built-in furniture is $17.14m^3$ 3) the proportion of optimal storage-capacity is 9.5% of the house-capacity.

• 한국농림기상학회지
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• 제16권4호
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• pp.327-335
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• 2014

현재 사용하고 있는 임목 재적표는 전국 공용으로 제작되어 있기 때문에, 특정 지역에 적용할 경우 재적을 과소 또는 과대 추정하는 문제점을 가지고 있다. 따라서, 본 연구는 이러한 문제점을 해결하기 위하여 수간곡선식을 이용하여 지역의 재적생장을 잘 반영할 수 있도록 홍천과 영주지역의 지방별 임목 수간재적표를 개발하고자 수행하였으며, 우리나라에서 가장 많은 분포를 보이고 있는 소나무를 대상으로 개발하였다. 추정에 적합한 수간곡선식의 도출을 위해서 Max & Burkhart, Korzak 그리고 Parresol et al.의 세 가지 수간곡선 모델을 적용하였으며, 적합도, 편의, 잔차의 표준 오차 등의 통계량을 분석하여 각 모델의 적합성을 평가하였다. 그 결과 3개의 수간곡선 모델간에는 정확성에 대한 유의적인 차이가 없으나, 소나무의 수간생장을 표현하는 데에는 Kozak 모델이 가장 적합한 것으로 나타났다. 따라서 Kozak 모형을 이용하여 소나무의 지방별 수간재적표를 조제하였다. 새롭게 개발된 지방별 수간재적표와 전국단위의 소나무 수간재적표와 비교한 결과, 홍천과 영주 2지역 모두에서 현재 재적표보다 재적이 높은 것으로 나타났으며(0.000< ${\alpha}=0.05$), 또한 두 지역간 지방별 재적표의 재적에서도 통계적으로 유의한 차이를 보였고(p-value: 0.000< ${\alpha}=0.05$) 홍천이 영주에 비해 재적이 높게 나타났다.

• 한국산림과학회지
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• 제109권3호
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• pp.281-290
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• 2020

본 연구는 식재밀도가 느티나무 조림목의 초기 생장에 미치는 영향을 구명하고자 수행되었다. 연구지는 경북 경산과 전북 순창이며, 2015년 3월 말 느티나무 노지묘(1-0)를 4처리 밀도(3천, 5천, 7천, 10천본 ha^-1)로 식재하였다. 2019년까지 매년 9월에 조림목의 근원경과 수고를 측정하였고, H/D율과 수간 재적을 계산하였다. 모든 조사지에서 식재밀도가 증가할수록 근원경 및 수고 생장이 높아지는 경향을 보였으며, 수간 재적은 10천본 ha^-1 처리구에서 가장 높게 나타났다. 그러나 생존율과 H/D율은 식재밀도에 따른 차이가 없었다. 식재후 5년차에, 경산 지역에서의 근원경, 수고, 수간 재적은 순창 지역에서보다 높게 나타났다. 그러나, 입지 환경이 다른 두 조사지 모두에서 식재밀도 증가에 따라 조림목의 초기 생장이 향상되는 동일한 경향을 확인할 수 있었다. 본 연구는 10천본 ha^-1의 식재밀도가 느티나무 조림목의 초기 생장을 향상시키기 위한 적정 식재밀도임 확인하였으며, 느티나무의 조림학적 특성으로서 밀식처리에 의해 초기 생장이 향상될 수 있다는 점을 제안한다.

• 한국산림과학회지
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• 제111권4호
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• pp.613-621
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• 2022

본 연구는 5차, 6차, 7차 국가산림조사 자료 중 아까시나무가 우점종인 표본점을 수집하여, 산림조사 차수별, 기후대별(온대 북부, 온대중부, 온대남부, 난대지역), 해발고별(100 m 단위) 흉고직경, 입목본수, ha당 재적 및 지위지수의 변화를 구명하고자 하였다. 또한 용재로서 사용을 위한 기준인 벌기령을 산정하였다. 그리고 변화 구명은 통계처리 기법 중 분산분석과 Duncan 검정으로서 이행하였다. 흉고직경의 변화를 보면, 당연히 산림조사 차수에 따라 증가하였고, 기후대별로는 온대남부 지역에서 가장 생장이 좋지 않았으며, 해발고별로는 301-400 m 지점에서 가장 생장이 떨어지는 것으로 나타났다. ha당 입목밀도는 산림조사 차수별, 해발고에 따라서 서로 간 차이를 보이지 않았으며, 온대중부 지역에서 밀도가 가장 높고, 온대남부 지역이 가장 낮은 밀도를 보였다. ha당 임분재적은 산림조사 차수에 따라 증가하였고, 온대북부·온대중부 지역과 온대남부·난대 지역으로 크게 두 그룹으로 구분되며, 해발고 201-300 m에서 재적생장량이 가장 높았다. 지위지수는 ha당 임분재적 변화와 유사한 결과를 보여 주었다. 그리고 아까시나무의 ha당 재적변화를 알 수 있는 생장량 곡선은 Weibull 함수식으로 추정하였으며, 임분재적은 임령 50-60년에 이를 때 약 200 m³에 달할 것으로 예측되었다. 아까시나무를 밀원 자원이 아닌 용재로 이용하기 위한 기준인 재적수확최대벌기령을 계산한 결과 34년으로 나타났다.

• 콘크리트학회논문집
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• 제17권5호
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• pp.857-868
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• 2005

This paper deals with the accumulated damage in concrete structures due to the cyclic freeze-thaw as an environmental load. The cyclic ice body nucleation and growth processes in porous systems are affected by the thermo-physical and mass transport properties, and gradients of temperature and chemical potentials. Furthermore, the diffusivity of deicing chemicals shows significantly higher value under cyclic freeze-thaw conditions. Consequently, the disintegration of concrete structures is aggravated at marine environments, higher altitudes, and northern areas. However, the properties of cyclic freeze-thaw with crack growth and diffusion of chloride ion effects are hard to be identified in tests, and there has been no analytic model for the combined degradations. The main objective is to determine the driving force and evaluate the reduced strength and stiffness by freeze-thaw. For the development of computational model of those coupled deterioration, micro-pore structure characterization, pore pressure based on the thermodynamic equilibrium, time and temperature dependent super-cooling with or without deicing salts, nonlinear-fracture constitutive relation for the evaluation of internal damage, and the effect of entrained air pores (EA) has been modeled numerically. As a result, the amount of ice volume with temperature dependent surface tensions, freezing pressure and resulting deformations, and cycle and temperature dependent pore volume has been calculated and compared with available test results. The developed computational program can be combined with DuCOM, which can calculate the early aged strength, heat of hydration, micro-pore volume, shrinkage, transportation of free water in concrete. Therefore, the developed model can be applied to evaluate those various practical degradation cases as well.

• 한국세라믹학회지
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• 제33권8호
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• pp.855-862
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• 1996

The nucleation and the crystal growth rates of Ge-Se-Te chalcogenide glass by two step heat-treatment and its effect on the mechanical optical properties and water-resistance were determined. The maximum nuclea-tion and crystal growth rate were 2.1$\times$103/mm3 .min at 28$0^{\circ}C$ and 0.4${\mu}{\textrm}{m}$/min at 33$0^{\circ}C$ respectively. When the crystal volume fraction with crystal size $1.5mutextrm{m}$ was about 4% the (hardness and fracture toughness were about 117kg/mm2 and 6.0 MPa.mm1/2)respectively. The weight loss of crystallized glass in water was lower than parent glass($25^{\circ}C$ for 32 hrs : 0.03% 8$0^{\circ}C$ for 16 hrs : 0.1%) as 0.01% at $25^{\circ}C$, 0.03% at 8$0^{\circ}C$ for 16 hrs : 0.1%) at $25^{\circ}C$ 0.03% at 8$0^{\circ}C$ respectively. The IR-transmittance decreased with increasing crystal size and crystal volume fraction. The IR-transmittance of crystallized glass with the crystal size of $1.5mutextrm{m}$ (crystal volume fraction : 4%) presented 56% which was about 4% lower than that of parent glass.

• 한국양식학회지
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• 제20권3호
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• pp.194-198
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• 2007

Reproductive traits of Palaemon gravieri such as embryo size, number of embryo (fecundity), incubation period, larval development mode, larval development period, larval survival and larval growth were described and compared to analyze the correlation among those traits. Embryo volume is a primary factor determining other ensuing reproductive features. Egg volume was $0.042mm^3$ in the first developmental stage. Embryo volume in P. gravieri was comparatively small which is indicative of great number of embryo (y = 3.0161x + 0.0185 $R^2$ = 0.74 positive isometric relationship) and relatively long incubation period. Larvae survived from zoea 1 to post-larvae and it took 45 days at $22^{\circ}C$. Survival rate of the larvae was rather great in the early stage and thereafter steadily decreased. Daily growth rate of larvae in P. gravieri at $22^{\circ}C$ was 0.0195 mm on average. They grew steadily as time went by. Incubation period was between 10-14 days at $22^{\circ}C$. Larval development mode was almost complete planktotrophic. PNR (point of no return) appeared to be the third day on average. Survival rate of larvae without feeding declined rapidly between 3 and 4 days. Larval development period and stage frequency were 23-30 days and 11 stages which imply prolonged larval period and high mortality. The pattern of brood production followed fast successive parturial pattern. Most ovigerous female had mature ovary when they performed parturial molt soon after hatching (larval release).

• Journal of Forest and Environmental Science
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• 제30권1호
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• pp.101-106
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• 2014

The purpose of this research was to figure out the stand structure and growth characteristic with relation to DBH, height, and volume in sixteen Pinus koraiensis plantations of Gangwon province region. Age class was diversely distributed from age class II (16 yr) to age class VIII (77 yr), and, in terms of site index, sixteen regions were superior: nine regions 'high', seven regions 'middle'. The distribution of DBH by sites appeared a bell-shaped curve, and the number of trees was the most in diameter section of 18-22 cm. The dispersion of DBH was various with age and widest ranging from 18 cm to 58 cm in age class VII-VIII. The distribution of height was also a bell-shaped curve with the smaller deviation than the distribution of DBH, and most of trees were in height section of 14-18 m. The correlation of DBH and height was high (r=0.75), and the volume bigger than 1.0 $m^3$ was presented from DBH 35 cm, height 20 m.

• 보건행정학회지
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• 제23권4호
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• pp.343-348
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• 2013

Background: Price control alone may not successfully restrain growth in health expenditures. This study aimed to propose fee adjustment model suitable for Korea reflecting health service volume and to clarify applicability of the model by comparing actual conversion factor with estimated conversion factor from simulation of this model. Methods: Fee adjustment model was developed based on Alberta's fee adjustment formula in Canada and 7 alternatives were assessed according to diversely applied parameters of the model. Results: Estimated conversion factors of the tertiary care hospital and the hospital were lower than actual conversion factors, since the utilization of heath service has been increased. However, there was no big difference between estimated conversion factors and actual conversion factors of the general hospital and the clinic. Eventually this fee adjustment model could estimate proper conversion factor reflecting health service volume. Conclusion: This model may be applicable to the mechanism as determining conversion factor between insurer and provider via negotiation and controling growth in health expenditures.