• Computers and Concrete
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• v.6 no.3
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• pp.203-223
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• 2009

Regression analysis (RA) can establish an explicit formula to predict the strength of High-Performance Concrete (HPC); however, the accuracy of the formula is poor. Back-Propagation Networks (BPNs) can establish a highly accurate model to predict the strength of HPC, but cannot generate an explicit formula. Genetic Operation Trees (GOTs) can establish an explicit formula to predict the strength of HPC that achieves a level of accuracy in between the two aforementioned approaches. Although GOT can produce an explicit formula but the formula is often too complicated so that unable to explain the substantial meaning of the formula. This study developed a Backward Pruning Technique (BPT) to simplify the complexity of GOT formula by replacing each variable of the tip node of operation tree with the median of the variable in the training dataset belonging to the node, and then pruning the node with the most accurate test dataset. Such pruning reduces formula complexity while maintaining the accuracy. 404 experimental datasets were used to compare accuracy and complexity of three model building techniques, RA, BPN and GOT. Results show that the pruned GOT can generate simple and accurate formula for predicting the strength of HPC.

• Journal of Korean Society of Forest Science
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• v.98 no.5
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• pp.618-629
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• 2009

The objective of this study was to examine the impact of pruning (P treatment) and transplanting (T treatment) of Acer palmatum on cambial growth and compartmentalization of pruning wounds for one year after treatments. Changes of cambial electrical resistance (CER), sizes of pruning wounds, cambial growth of trunks and stems near the wounds, and total phenols at branch unions during the period were examined using a total of 49 trees. After harvesting, areas of discolored wood behind the wounds, relative proportions of extractives, holocellulose and lignin at branch unions were also determined. CER and the cambial growth of trunk at 30 cm above the ground (TGR) were inversely correlated, and differences of CER and TGR among three treatments were significant. TGRs of control, P treatment and P+T treatment after the treatments were 112.2%, 72.4% and 52.5% of the annual growth for the year before the treatments, respectively. The cambial growth rate of stem (SGR) at 1.5 cm above the branch bark ridge and the closure rate of pruning wound (WCR) for one year after treatments were positively correlated, and WCR of P treatment of 39.8% was significantly higher than that of P+T treatment of 31.8%. Wounds of P+T treatment formed greater discolored area per unit area of pruning wound (D/W Ratio) than those of P treatment significantly. Lower WCR and higher D/W Ratio of P+T treatment suggested less ability of compartmentalizing the wounds than P treatment. Total phenols at branch core of pruning wound for both treatments heightened a month after treatment, and then lowered. The contents at below core of the wound were higher than those at control ones continuously, while they became similar each other at above core. Relatively high phenol contents of the extractives at P+T treatment implied that trees with P+T treatment allocated more energy to compartmentalize their wounds. Holocellulose and lignin contents at the branch core of treated branch unions of both treatments were lower and higher, respectively, than at the same part of the union with living branch, as results of the tree reaction to protection from wounding and microbial invasion.

• The Journal of the Acoustical Society of Korea
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• v.20 no.7
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• pp.55-62
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• 2001

In this paper, we propose a new adaptative pruning algorithm which effectively reduces the search space during the recognition process. As maximum probabilities between neighbor frames are highly interrelated, an efficient pruning threshold value can be obtained from the maximum probabilities of previous frames. The main idea is to update threshold at the present frame by a combination of previous maximum probability and hypotheses probabilities. As present threshold is obtained in on-going recognition process, the algorithm does not need any pre-experiments to find threshold values even when recognition tasks are changed. In addition, the adaptively selected threshold allows an improvement of recognition speed under different environments. The proposed algorithm has been applied to a Korean Address recognition system. Experimental results show that the proposed algorithm reduces the search space of average 14.4% and 9.14% respectively while preserving the recognition accuracy, compared to the previous method of using fixed pruning threshold values and variable pruning threshold values.

• Journal of Korean Society of Forest Science
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• v.99 no.2
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• pp.226-234
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• 2010

This study was conducted to examine the effects of pruning season on the compartmentalization of pruning wounds in Acer palmatum and Pinus strobus. A total of eighty five field-grown trees for each species were allocated to five different seasons, early- and late-winter, mid-spring, mid- and late-summer, for pruning treatments. Wound closure rate (WCR) of the two species for one year after treatment, area of discolored stem tissue on the medial longitudinal surface and cambial dieback length under the pruning wound of A. palmatum were measured. Changes of total phenols and variations of extractives, holocellulose and lignin at the treated branch unions were examined. In WCR of A. palmatum, late-winter (March, 39.8%) and mid-spring (May, 39.7%) were higher than any other seasons, while early-winter (November, 28.4%) was significantly lower than late-winter and mid-spring. P. strobus showed similar results with A. palmatum. The WCR of early-winter (57.2%) was the lowest significantly among the five seasons, and mid-spring (73.5%) and late-winter (71.4%) showed higher a WCR than other seasons. In the discolored/wound area ratio of A. palmatum, early-winter (73.2%) was the highest by far, and mid- (July) and latesummer (September, 36.7%, respectively) were the lowest among the five seasons. In the length of cambial dieback, two dormant seasons, early- and late-winter were longer than any other seasons. Phenol contents at the treated branch union were changed in line with the seasonal fluctuation of the tree. Total phenols in the below core of the treated union were higher than those of the branch union with living branch, while little differences were seen in the above core. At the branch core of the treated union, phenols of A. palmatum decreased one month after the treatments, but P. strobus maintained similar to or a little higher than those at the controls. The major changes in chemical composition at pruning wounds were extractives and lignin increased by less than 20% in A. palmatum, while extractives in P. strobus remarkably increased by 70%.

• Journal of the Korean Institute of Landscape Architecture
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• v.44 no.5
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• pp.59-67
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• 2016

In landscape design by public institutions, although the costs and species of landscape trees stipulated by the Korean Public Procurement Service(PPS) are generally adhered to, the PPS regulations about planting trees with well-developed rootlets are almost entirely neglected. This study aimed to evaluate the performance of buried container modules, which are a new technology and product in landscape production that is able to reduce the defect rate while complying with regulations. To this end, this study measured rootlet density, rootlet development length, rootlet survival rate on excavation, and impairments of tree growth for 3 months after root pruning, and compared these variables for the container modules with those for trees that underwent root pruning in bare ground, and those that were cultivated in a container above ground. The results were as follows: First, the rootlet density was 88% for the trees in container modules, which was very high. Trees that underwent standard root pruning in bare ground had a somewhat lower density of 64%. Meanwhile, the trees that were cultivated in pots above ground died, invalidating measurement. Second, in terms of rootlet development and rootlet survival rate, the trees in container modules showed a mean length of 10.4cm, and 100% survival rate, indicating that there was no rootlet damage caused by excavation. For the trees that only underwent root pruning in bare ground, the mean length was 25.6cm and the rootlet survival rate was only half that of the trees in container modules, at 56%, demonstrating considerable damage. Rootlet development did not occur at all in the trees grown in pots. Third, the trees in container modules and those that underwent root pruning in bare ground did not show any deaths during the root pruning process, or any impairments such as stunted leaf growth. Conversely, the trees grown in pots nearly all died, and severe impairments of tree growth were observed. As shown by the results above, when we evaluated the performance of buried container modules, they showed the most outstanding performance of the three models tested in this study. The container modules prevent defects by stimulating early rooting in environments that with poor conditions for growth, or in trees that are not suited to the summer environment Therefore, it is expected that they would be an optimal means by which to enable compliance with rules such as the regulation presented by the PPS.

• Korean Journal of Soil Science and Fertilizer
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• v.46 no.2
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• pp.136-141
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• 2013

Lowering tree height has been a key practice for efficient management of persimmon orchards. This experiment was conducted to assess whether fertilization rates could be reduced after lowering the tree height by heavy pruning. Twelve-year-old 'Uenishiwase' persimmon trees were lowered to 2 m from over 3 m by severe dormant pruning, and then conventional fertilization rate was applied to some trees in April (N 224 g, $P_2O_5$ 172 g, and $K_2O$ 172 g per tree), June (N 112 g and $K_2O$ 99 g per tree), and October (N 112 g and $K_2O$ 99 g per tree). At the same time, 1/3 or 2/3 of the conventional rate and none were applied to other trees, respectively. Non-application decreased shoot length and reduced number of unnecessary secondary shoots by 39% compared with the conventional rate, not affecting yield and weight, color, firmness, and soluble solids of fruits. No significant difference was also found in the yield and the fruit characteristics among the trees fertilized with different rates. Concentrations of soluble sugars, starch, N, and K of dormant shoots in March of the following year were not significantly changed by the different treatments of the previous year. There was no significant difference of shoot growth and yield among the treatments the following year when the same fertilization rate was supplied to all the trees. Results indicated that fertilization rate could be reduced to less than 1/3 of conventional rate to save the cost and stabilize shoot vigor when tree height is lowered by severe pruning.

• Journal of Korean Society of Forest Science
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• v.111 no.4
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• pp.557-566
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• 2022

This study aimed to obtain basic data on high-quality fruit production and efficient cultivation of persimmon cultivar "Godongsi". In the second year of pruning, the number of fruits per tree according to the number of fruit-bearing mother shoots (300, 400, 500, and 700 [control] treatments) was 676.3, 786.0, 866.7, and 1238.7, respectively. Persimmon cultivar "Godongsi" had a decrease in number of fruits per tree and increase in fruit weight as the pruning intensity increased. The average fruit weight in the 300 treatment group was 212.2 g, which was 1.5 times heavier than that in the control. For a high-quality dried persimmon processing, the rate of grade L fruits (170 g<ｘ≤200 g) and over according to the number of fruit-bearing mother shoots was 86.9%, 48.6%, 33.5%, and 8.1%, respectively. The fruit grade of the pruned treatment group was significantly higher than that of the control. Based on the selling price of dried persimmon, the production amount was significantly higher in the 300 treatment than that in the control. When there were many fruits per tree, there was a decrease in quality and increase in cost of harvesting and processing. In conclusion, pruning is essential to increase the fruit quality (fruit weight and grade) of persimmon cultivar "Godongsi". Moreover, the suitable number of fruit-bearing mother shoots was 300.

• Journal of KIISE:Databases
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• v.31 no.2
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• pp.91-98
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• 2004

DHP mining association rules algorithm maintains previously independent direct hash table to reduce the sire of hash tree containing the frequency number of each candidate large itemset. It performs pruning by using the direct hash table when the hash tree is constructed. The mort large the size of direct hash table increases, the higher the effort of pruning becomes. Especially, the effect of pruning in phase 2 which generate 2-large itemsets is so high that it dominates the overall performance of DHP algorithm. So, following the speedy trends of producing VLM(Very Large Memory) systems, extreme increment of direct hash table size is being tried and one of those trials is perfect hash table in phase 2. In case of using perfect hash table in phase 2, we found that some rearrangement of DHP algorithm got about 20% performance improvement compared to simply ｜H$_2$｜ reconfigured DHP algorithm. In this paper, we examine the feasibility of perfect hash table in phase 2 and propose PHP algorithm, a rearranged DHP algorithm, which uses the characteristics of perfect hash table sufficiently, then make an analysis on the results in experimental environment.

• Korean Journal of Environment and Ecology
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• v.27 no.2
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• pp.253-265
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• 2013

This study was correlation analysis between provision and management of street green and street environment through field survey about city official roads(93 routes, 629.2km) in Seoul. Green belt under the street trees were 17.5% of all routes. Composition of street green belt width of 1~ 2m was the most common(11.6%). Management status as a protected facilities were protect frame and prtect cover installed inerval(60.1%). Interval of pruning was 63.5%. Type of tree was mainly 47.9%. Road width was mainly more than 8-line(51.3%). Sidewalk width was mainly 3~6m(84.1%)in environment status of street. Landuse was mainly commercial and business(70.3%). Electronic wire complete was mainly compete with crown(33.6%). Use of sidewalk was mainly used(16.3%). ANOVA analysis was conducted between the Street green and environment of Street. Street green belt(more than with 3m) was analyzed to be effective in street green manufacture. Natural green area of city's outside and Industrial area were analyzed to be effective. Use of sidewalk was to be a management. Protection facilities are installed on the narrow sidewalk width lower intensity. There was a higher strength in narrow sidewalk width, road width and compete with crown. And type of tree was higher strength similarly. Pruning and type of tree showd a significant correlation. Thus, ensure sufficient sidewalk width and land use should be considered for street green was effective manufacture and management. Species selection and pruning management was needed by consider electronic wire management, type of tree and landscape.

• Journal of the Korean Institute of Landscape Architecture
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• v.51 no.2
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• pp.94-102
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• 2023

The Florence Charter, established in 1981 by the ICOMOS-IFLA International Commission on Historic Gardens, considered the historic garden as a plant-dominated architectural composition, a perpetual balance between the artist and the artisan's desire to remain unaltered in perpetuity. Trees, the main component of the garden, require continuous management as they repeat their creation and calling according to the cycle of the seasons and accordingly, it is suggested that management to maintain the appearance of trees in Korean palaces was an indispensable element. Although it is an important matter to historically verify the tree management techniques of the palaces of the past, research has been difficult due to the absence of historical records and the disconnection of life due to the Japanese colonial period. In addition, according to the view that trees were not generally managed in the palace, research on palace tree management techniques has not been conducted so far. Therefore, this study aimed to examine whether or not the tree management of the palaces was performed in the past through expert interviews based on photographs taken in modern times. With the identification of tree species and pruning through in-depth interviews with experts using photographs taken in the modern period, the results are as follows. First, it was found that the shapes of trees and leaves could be identified through photographs and by observing the phenomena caused by planting and pruning, it was possible to estimate whether or not the tree management was implemented in the modern palace. Second, as a result of in-depth interviews with 8 experts in 4 fields, it was possible to determine the tree species and pruning status, purpose, and method. There was no significant difference in opinions between groups, and the evidence was clearly presented. Third, the type of management of trees in the palace was mainly found to be determination of the types of tree, removal of hazardous factors of trees, and management of lower vegetation and through the photographs of Jondeokjeong and Gwanwanjeong, it was confirmed that the trees were managed even before the Japanese colonial era, considering the time of filming. Based on the photographs taken, it was possible to estimate whether the trees were managed before the Japanese colonial period through expert interviews. However, it could not be clarified due to lack of historical materials as to whether it was carried out on its own according to the circumstances of the times or by the Japanese Empire. Still, in this study, evidence was obtained to refute the view that trees of the palace were not managed in the past through the collected data. Expert opinions supporting this view were collected to make the conclusion. In addition, based on the general theory of pruning, an empirical review of expert opinions was conducted to secure the reliability of the research results.