• 한국산림과학회지
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• 제90권4호
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• pp.458-464
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• 2001

본 연구는 토양 산성화 정도가 서로 다른 독일가문비나무 임분에서 토양 깊이에 따른 뿌리의 나이테 발달과 분지형태를 분석함으로서, 임분에 따른 뿌리발달을 비교하고자 하였다. 조사된 독일가문비나무 임분에서 뿌리분지구조는 변형된 뿌리와 변형되지 않은 뿌리에 대한 조사임분간의 통계적 유의성이 인정되지 않았지만, 가장 많이 산성화된 Weidenbrunnen 임분에서는 뿌리가 상해를 입음으로 인해 발생되는 포크형, 권총형, 쇠스랑형과 같은 비정상적인 분지구조가 많이 나타났다. 뿌리의 나이테 분석 결과, 수평뿌리의 연평균 길이생장은 Weidenbrunnen 임분과 Barbis 임분이 6.3cm, Eberg$\ddot{o}$tzen 임분이 9.5cm의 길이 생장을 나타내었으며, 수직뿌리의 연평균 길이생장은 Weidenbrunnen 임분이 4.4cm Barbis 임분이 5.4cm, 그리고 Eberg$\ddot{o}$tzen 임분이 6.7cm의 생장을 보였다. 80cm 토양 깊이에서의 뿌리 횡단면 분포는 Eberg$\ddot{o}$tzen 임분이 굵은 뿌리와 가는 뿌리가 고르게 분포하고 있으며, 횡단면의 합계는 $32.6cm^2$ 이었다. Barbis 임분에서는 굵은 뿌리가 가운데 몰려서 분포하고, 가는 뿌리는 비교적 적게 나타났으며, 그 합계는 $29.2cm^2$이었다. Weidenbrunnen 임분에서는 적은 수의 가는 뿌리만 분포하고 그 값은 $10.9cm^2$에 불과하였다. 뿌리고정계수는 Eberg$\ddot{o}$tzen 임분이 1.04로 다른 두 임분 Barbis(0.3), Weidenbrunnen (0.08)과 비교하여 매우 높은 값을 나타내었다. 본 조사 독일가문비나무 임분 중에서 Weidenbrunnen 임분에서 나타난 비정상적인 형태의 변형된 분지구조와 뿌리의 저조한 생장은 토양산 성화 등으로 인하여 정상적인 뿌리가 생장의 장애를 받아 나타난 결과 때문이라 사료된다.

• Journal of Plant Biology
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• 제14권4호
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• pp.19-26
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• 1971

The sample stand of Pinus rigida plantation was chosen from those at the Choongnam Forest Experiment Station, Choongnam. The diameter at breast height (D) and the height of tree (H) of each tree in the sample plot of 200$m^2$ were measured yearly a from 1967 through 1969. The stand was 12.7-13.4cm in mean diameter and had a stand density of 2,150 trees per ha. The trunk, branches and leaves of each sample tree were separately weighed according to the stratified clip technique. The allometric relation between D2H and dry weight of trunk (Ws), branches (Wb) and leaves (Wl) were approximated by $$W_s=0.05917 (D^2H)^{0.837}$$ $$W_0=0.00655 (D^2H)^{0.989 }$$ $$W_l=0.04466(D^2H)^{0.690}$$ From the above, the standing crops in the sample stand was estimated to be as much as 76.7, 81.7 and 88.2 tons of dry matter, above ground, per ha in 1967, 1968 and 1969, respectively. Annual net production, as the sum of the biomass newly produced during one year, was estimated at 4.97-5.47 tons per ha per year. The respiratory and the photosynthetic rate deduced from theoretical calculations were 0.045 and 0.74kg of dry matter per kg per year. Tentative estimate of annual respiratory loss was made and annual gross production was roughly estimated at 4.4-4.7 and 10.7-12.9 tons of dry matter per ha per year. The ratio of respiratory loss to gross production was approximately 36-41:1.

• Physical Therapy Rehabilitation Science
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• 제6권2호
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• pp.96-104
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• 2017

Objective: The purpose of this study was to investigate the effect of the hip joint strengthening exercises using proprioceptive neuromuscular facilitation (PNF) on the clinical symptoms and the treatment effects in balance, sit to stand, and gait abilities in patients with TBI. Design: A single case study. Methods: A 13-year-old adolescent with quadriplegia and hip joint control impairment participated in this four-week training intervention. The patient, diagnosed with TBI, wastreated with hip joint strengthening exercises using PNF. In the first week, we focused on strengthening the body, relaxing the hip flexors and activating the hip extensor muscles in order to solve the patient's physical function and body structure. From the 2nd and 4th week, we improved the motivation through the task-oriented method, and then weight-bearing training of the right lower extremity was proceeded by kicking a soccor ball with the left lower extremity. The exercises were performed for 4 weeks, 5 days a week, for 60 minutes with the exercise intensity gradually increased according to the subject's physical abilities. Results: As a result of the study, the patient demonstrated improvements in the physical examination, which were evaluated before and after intervention and included the manual muscle test, modified Ashworth scale, sensory assessment, coordination assessment, Berg balance scale, 5-time sit to stand test, and the 10 meters walk test. Conclusions: The results of this case suggest that a hip joint strengthening exercise program using PNF may improve hip control ability, balance, sit to stand and gait ability in a patient with TBI.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2001년도 가을 학술발표회 논문집
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• pp.475-482
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• 2001

Stadium stand could be led to significant dynamic response due to rhythmical activities of spectator. The dynamic loads induced by spectators movements are considered as static loads in design standard of many countries but these loads have dynamic characteristics. So, it is desirable to apply measured dynamic loads created by spectator activities and to analyze the dynamic behavior of stadium system. The precise investigation of the dynamic loads on stadium structures and the accurate analysis of dynamic behavior of stadium systems are demanded for effective design. As the floor mesh of stadium stand is refined, the number of nodes increase in numerical analysis. So it is difficult to analyze entire stadium structures and much more computer memory are necessary for vibration analysis of stadium system. In this study, the various dynamic loads induced by spectator movements are measured and analyzed. And new modeling method that reduce the nodal points of stadium systems are introduced. Vibration analysis of stadium system is executed to inspect the accuracy and the efficiency of proposed method in this paper.

• Wind and Structures
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• 제17권6호
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• pp.671-680
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• 2013

Static aeroelastic is investigated in a wind turbine blade. Imposed to different loadings, the very long and flexible structures of blades experience some changes in its preliminary geometry. This results in variations of aerodynamic loadings. An iterative approach is developed to study the interactions between structure and aerodynamics evaluating variations in induced stresses in presence of aeroelasticity phenomenon for a specific wind turbine blade. A 3D finite element model of the blade is constructed. Aerodynamic loading is applied to the model and deflected shape is extracted. Then, aerodynamic loadings are updated in accordance with the new geometry of the deflected blade. This process is repeated till the convergence is met. Different operational conditions consisting of stand-by, start-up, power production and normal shut-down events are investigated. It is revealed that stress components vary significantly in the event of power production at the rated wind speed; while it is less pronounced for the events of normal shut-down and stand-by.

• 전력전자학회:학술대회논문집
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• 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
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• pp.972-977
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• 1998

This paper deals with stand-alone Photovoltaic system(SPVS) with charge and discharge controller. Main power source of SPVS are generally solar cell and battery. Therefore SPVS can be classified into variable types in accordance with connection method between battery and solar cell array. Mainly used one of them is direct connection type which has advantages such as simple structure and simple controller. However most big drawback of this system is energy loss by voltage disharmony between solar cell array and battery. Therefore SPVS with charge and discharge controller which can operate solar cell array at maximum power point is designed and experimented with a laboratory prototype.

• PNF and Movement
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• 제9권4호
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• pp.41-48
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• 2011

Purpose : The purpose of this study was to assess the tibialis anterior, soleus, gluteus maximus, transverse abdominis muscle activity of tibialis anterior, soleus, gluteus maximus, transverse abdominis according to pronated foot and supinated foot. Methods : Group of pronation and supination were taped using augmented low-day method to make pronated and supinated foot the three case were assessed by agnostic radiology for investigating foot structure. Results : 1) When supinated foot & pronated foot, tibialis anterior & gluteus maximus muscle activity was augmented in one step. 2) When supinated foot & pronated foot, soleus & transverse abdominis muscle activity was decreased in one step. 3) When supinated foot & pronated foot, tibialis anterior & gluteus maximus muscle activity was augmented in squat. 4) When supinated foot & pronated foot, soleus muscle activity was decreased in squat. 5) When pronated foot, transverse abdominis muscle activity was decreased in squat. 6) When supinated foot, transverse abdominis muscle activity was augmented in squat. 7) When pronated foot, transverse abdominis & gluteus maximus & tibialis anterior muscle activity was augmented in sit to stand. 8) When supinated foot, transverse abdominis & gluteus maximus & tibialis anterior muscle activity was decreased in sit to stand. 9) When supinated foot & pronated foot, soleus muscle activity was decreased in sit to stand. Conclusion : 1) Pronated foot & supinated foot effects on soleus, gluteus maximus, transverse abdominis muscle activity in one step. 2) Pronated foot & supinated foot effects on tibialis anterior, gluteus maximus, transverse abdominis muscle activity in squat. 3) Pronated foot & supinated foot effects on soleus, transverse abdominis muscle activity in sit to stand. Therefore we suggest the deformity of the foot effects on tibialis anterior, soleus, gluteus maximus, transverse abdominis muscle activity.

• 한국산림과학회지
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• 제97권5호
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• pp.501-507
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• 2008

The data of crown width with 4 directions, DBH, tree height, and coordinate for sample trees were collected from 30 permanent sample plots in secondary fore st of the Maoershan Experimental Forestry Farm, Northeast China. In this paper, the competition of individual trees in stand were discussed for secondary forest by using iterative Hegyi competition index and crown overlap index that represented the competitive and cooperative interactions among neighboring trees. Active competitors of subject tree in the competition zone were selected to calculate the iterative competition index. Using the results of crown classification based on the equal crown projection area, a new distance dependent competition index called crown overlap index (COI) was developed for secondary forest. The COI performed well in describing the crown competition rather than crown competition factor (CCF). The individual-based competition index discussed in this paper will provide more precise for developing individual tree growth models for secondary forest and it can also use to adjust the stand structure for spatial optimal management.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.512-514
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• 2005

Accurate DEM surface of forest floor is very important to extract any meaningful information regarding forest stand structure, such as tree heights, stand density, crown morphology, and biomass. In airborne lidar data processing, DEM data of forest floor is mostly generated by interpolating those elevation points obtained from last laser returns. In this study, we try to analyze the property of the last laser return under relatively dense forest canopy. Airborne laser data were obtained over the study area in relatively dense pine plantation forest. Two DEM data were generated by using all the points in the last laser returns and using only those points after removing non-ground points. From the preliminary analysis on these DEM data, we found that more than half of points among the last laser returns are actually hit from canopy, branches, and understory vegetation that should be removed before generating the surface DEM data.

• Journal of Plant Biology
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• 제22권3호
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• pp.59-62
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• 1979

Distribution and standing crops of seedling and sapling as undergrowing tree were investigated in a Pinus rigida forest. The relative light intensity(RLI) on the ground level was 3.9∼59.3% which indicates a wide range. Under this range of RLI seedlings and saplings distribute well in the stand. Eight trees were selected from the stand, then measured dry weight of stem, branches and leaves using thestratified clip technique. A possible relationship between the diameter at the bottom of the tree (Do) and standing crops was investigated. As Do increased from 0.8cm (T1) to 7.2cm (T8), the standing crops also increased from 42.6g to 7,410.4g. Since semi-log values between Do and standing crops clearly indicates a straight line, there is close relationship between these two factors. Therefore it is possible to estimate the standing crops of seedling and sapling by measuring Do. Productive structure shows that phytosynthetic layer is located above the 1/2 height of the tree and maximum photosynthetic layer apperars on 2/3 level in height.