• Journal of Environmental Science International
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• v.23 no.6
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• pp.1075-1083
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• 2014

The objective of this study was to evaluate the effect of cutting types on microclimate and growth characteristics of afforested tree in Quercus acutissima stand after different types of cutting. The difference in temperature reaching $5.2^{\circ}C$ was shown in between clear cutting and selective cutting treatments. On July and August days with temperatures more than $35^{\circ}C$ often appeared in clear cutting stand. The values of VPD in July and August were higher than those in other months. Maximum VPD of 3.99 kPa was shown in clear cutting stand on May 23 as a prolonged rainless days appeared. However, VPD in selective cutting stand always stayed under 3.0 kPa throughout growing season. A higher intensity was shown in clear cutting and strip clear cutting stands, reaching to more than $1,600{\mu}mol\;m^{-2}s^{-1}$ at midday on early August, while that in selective cutting stand stayed about 1,500. In relative growth rate selective cutting stand showed a significantly higher relative growth rate in plant height than those in other cutting stands (p<0.05). The number of leaf in current-year branches significantly increased in selective cutting stand, whereas no increase was shown in clear cutting and strip clear cutting stands (p<0.05). In addition, relative elongation rate of current year branch also showed higher values in selective cutting stand compared with that in strip clear cutting stand (p<0.05). However, leaf mass per unit area (LMA) was higher in order of strip clear cutting, clear cutting, and selective cutting stands. From these results it is concluded that environmental conditions in clear cutting and strip clear cutting stands during growing season are more stressful to afforested tree species, resulting in lower relative growth in plant height, elongation of current-year branches, and leaf number per branch compared with those in selective cutting stand. Consequently, more data must be accumulated in the field to find out best cutting type in plantation considering the adaptational characteristic of each tree species varies with species and life span of tree is long.

• Journal of Forest and Environmental Science
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• v.16 no.1
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• pp.34-41
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• 2000

This study investigated tree vigor of damaged forest by Thecodiplosis japonensis Uchida et Inouye. In damaged forest by pine gall midge, the investigation result of damaged rate section (severe, moderate, light) indicated that severe stand showed higher value of electric resistance ($k{\Omega}$) than that of light stand, the investigation result of tree density section(crowed, middle, little) indicated that crowed stand showed higher value of electric resistance than that of little stand (the value of electric resistance at which low reading show high vigor tree and high reading low vigor tree). The crown width and DBH (diameter of breast height) of external factors showed lower value of electric resistance than that of small size. The results of comparative between Crown area and value of electric resistance in each stand were $13.4m^2$ in severe stand, $10.9m^2$ in moderate stand and $7.9m^2$ in light stand. Therefore, the tree which have big crown showed low value of electric resistance (below $15k{\Omega}$)that has high possible of survial.

• Journal of Korean Society of Forest Science
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• v.83 no.1
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• pp.63-74
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• 1994

One of the essential factors to estimate the stem and stand growth is to correctly portray a stem form (profile). It is also required to numerically approximate a stem form in order to dynamically grasp and represent a stand growth. A whole stem form seems to be a conical form but a stem outline at various positions tapers off differently. Accordingly it is difficult to model a whole stand form with single taper equation. A stem taper equation with different coefficients on each subinterval can be useful tools to accurately portray a stem form. This article presents the derivation method of individual stem taper curve using spline function. It is also in this paper aimed to study how a stand taper curve car, be derived from the population of single stem taper curve in a stand. These taper equations numerically formulated enable to dynamically represent and prognosticate the development process of a stand and prepare the foundation of variety on growth model study and rational forest planning model.

• Journal of Korean Society of Forest Science
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• v.89 no.4
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• pp.502-512
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• 2000

Old-growth development for two different second-growth northern hardwood stands in the North America was evaluated with a computer simulation. The two sites compared were a representative 77 year old even-aged stand (Phelps) with heavy dominance by pole size classes, and an older uneven-aged stand with some existing old-growth structural features (Wildcat Creek). Each stand was evaluated in its natural progress toward old-growth structural conditions with stand structure, size distribution of live and dead trees, percent stand area in canopy gaps, and visual canopy profile and overhead view. The Phelps stand reached the minimum structural threshold for the old-growth stage after 74 years. Only 13 years was required for Wildcat Creek stand to reach the old-growth threshold. During the 45 years of simulation, the diameter distributions of both stands became broader and flatter. DBH distribution of dead trees had a general descending trend over the simulation in each stand. Gaps at Phelps were typically small after 45 years. Gap area at Wildcat Creek was somewhat more constant over the 45 years of simulation but a big gap was formed because of the death of several adjacent large trees.

• Journal of Biosystems Engineering
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• v.22 no.3
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• pp.311-316
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• 1997

Two methods were used to detrermine the net photosynthetic rate(NPR) in the plug stand using a wind tunnel for plug seedlings Production. One is called as the integration method in which NPR calculated by the use of air current speed and $CO^2$ concentration measured at any heights above the medium surface in a wind tunnel were summed. It was assumed that the air flow at any layer did not mix with the lower or upper air layer. The other is called as the diffusion method in which eddy diffusivities above the plug stand were used to determine the NPR in the plug stand. In this method, $CO^2$ above or inside the plug stand was assumed to be absorbed vertically. NPR determined by the diffusion method was 28~45% of the NPR calculated by the integration method. Considering the magnitude of NPR and the effects of the air current speed on NPR, the integration method would be adequate for the calculation of NPR in the plug stand. Maximum NPR determined using the integration method appeared at the air current speed of 0.7m $s^{-1}$. It was ascribed to the decreased diffusion resistances of $CO^2$ with the increasing air current speed. NPR at the rear region in plug stand was 20~34% lower than that at the front region. NPR sharply decreased with the increase of an elapsed time after the beginning of photoperiod. Therefore $CO^2$ enrichment would be effective to force the growth of plug seedlings in a semi-closed ecological system under artificial lighting.

• Journal of the Korean Society of Clothing and Textiles
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• v.39 no.6
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• pp.826-837
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• 2015

This study analyzes the shapes of the adjustment of a Napoleon Collar which combines a stand collar with an upper collar. It established experimental conditions for fixing the conditions of Napoleon Collar components (lapel width, stand collar size and upper collar size) as well as varied the shape of the neckline, the length of the curve of a stand collar and the size of the drawing space at the center back. It produced 22 test clothes of muslin, which were dressed on dress form No. 8. The results indicate that: 1. Neckline shape determines the amount of stand and fall. Less curved neckline stands higher against the neck and a more curved neckline is laid lower onto the body. 2. A shorter curve length of a stand collar allows a longer roll line to fall farther away from the neck with more space between the neck and collar. However, the longer the depth of curve of a stand collar creates a shorter roll line that stands high against neck and closer to neck without any space between the neck and collar with a collar line matching the neck of the dress form. 3. The smaller the drawing space at the center back creates a shorter the style line of the upper collar. However, a narrower back width of the collar creates a bigger drawing space at the center back with a longer the style line and a more naturally placed back width of the collar. 4. A Napoleon Collar creates a longer depth of curve for a stand collar and a smaller drawing space at the center back that is tightly and stably stuck to the neck.

• Journal of Korea Foresty Energy
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• v.20 no.2
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• pp.46-57
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• 2001

This study was conducted to provide tending operation information for the effective management in unmanaged artificial forests of Pinus densiflora for. erecta, Pinus rigida, and larix leptolepis, based on the study of the comparison of tree growth pattern by residual stand density after thinning practices. Followings are summarized results of this study. 1. The diameter growth of residual trees was increased as residual stand density decreased by thinning practices in the stands of Pinus densiflora for. erecta, and Pinus rigida, and subcompartment (Ga) and (Na) of Larix leptolepis. The statistical analysis noted that the tree growth was significantly different by the residual stand density. 2. The height growth did not show corresponding results by stand density treatment pattern, which indicated that the height growth was not directly influenced by residual stand density, but by site quality of the stand. 3. The diameter increment for the last six years was proportionately increased in larger diameter classes and less dense stands.

• Physical Therapy Korea
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• v.20 no.3
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• pp.1-8
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• 2013

The purpose of this study was to determine the effectiveness of sit-to-stand training on unstable surfaces in individuals with stroke. Nineteen subjects with chronic stroke were divided into two groups: an experimental group (10 subjects) and a control group (9 subjects). They received 30 minutes of Neuro-developmental therapy (NDT) treatment, and sit-to-stand exercise for 15 minutes three times a week for four weeks. During the sit-to-stand training, the experimental group performed on an unstable AIREX balance pad, but the control group performed on a stable surface. Balance ability and weight-bearing distribution during quiet standing were measured before and after training period using the 7-item Berg balance scale-3P (BBS-3P) and the Five-times-sit-to-stand test (FTSST). In addition, the muscle strength of the knee extensor was evaluated before and after the training period. The results were as follows: 1) The weight-bearing distribution forward of the affected leg, increased significantly in the experimental group after the four-week intervention (p<.05), 2) The 7-item BBS-3P and FTSST increased significantly in the experimental group after the four-week intervention (p<.05), 3) The knee extensor muscle strength in both groups increased significantly after the four-week intervention (p<.05). In conclusion, the results of this study did not show that the sit-to-stand training on an unstable surface was more effective than on a stable surface. However, the results suggested that sit-to-stand training is effective in the balance training of stroke patients.

• Journal of Korean Society of Forest Science
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• v.88 no.4
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• pp.446-453
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• 1999

In this study, the effects of stand planting density on parameters of stand height and basal area growth models were investigated. We used the Korf equation as the base model in estimating the parameters of the growth models for cryptomeria plantation forest stands. Then, in order to investigate the effects of the change in plantation density on the parameter estimates, the "extra sums of square" principle, which provided a reasonable statistical procedure for a performance test, was used. The results of the test coincide with the understandings that stand height growth is not affected significantly by the planting density and the growth curves of stand basal area approaches a common asymptote regardless of the stand density for a given site. However, the shapes of the basal area growth curves were affected significantly by the planting density. Based on the results of the test, we developed a basal area growth model to account for the effects of initial planting density in cryptomeria plantation forest stands.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.116-123
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• 2018

The objective of this study was to examine effects of stand age on soil $CO_2$ efflux in plantation Pinus koraiensis, and to elucidate what extent plant (fine) root and soil microbial biomass contribute to the whole soil $CO_2$ efflux. In three age classes (20-yr-old. 40-yr-old, 70-yr-old) of plantation Pinus koraiensis, in-situ soil respiration, plant fine root biomass and soil microbial biomass were measured from April to November in 2004. Regardless of stand age, soil temperature and soil $CO_2$ efflux increased until July then slowly decreased. Soil respiration was higher in 70-yr-old stand than in 20- and 40-yr stands. Fine root biomass and soil microbial biomass was also higher in 70-yr-old stand. Root exclusion decreased soil respiration in 40-yr stand, but not in 70-yr stand. Soil microbial biomass was higher in 70-yr stand, but there was no monthly variation between July and November. The results suggest that soil respiration may increase as plant stand ages and microbial contribution could play more roles in older stands.