• The Korean Journal of Ecology
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• v.22 no.5
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• pp.277-285
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• 1999

To develop a better restoration technique for altering urban planted forest to more natural forest, the changes of flora, vegetation structure and woody plant growth in the early stage after lumbering only Populus albaglandulosa of the tree layer were studied in Chungdam Park, Chungdam-dong, Kangnam-gu, Seoul for two years (from 1997 to 1998). The results were as follow. First, in the year after lumbering, the species changes occurred not in woody plants but in herbs, which increased by 44%. Three species including Viola verecunda disappeared, and 15 species including ruderals such as Metaplexis japonica and introduced species such as Erechtites hieracifolia appeared newly. Second, lumbering caused the coverages of Quercus aliena, Q. mongolica, Q. acutissima and Sorbus alnifolia in the subtree, or shrub layer, to be increased abruptly. The coverage of Lespedeza bicolor was affected by neighboring plants. Third, in the herb layer the coverage of Artemisia keiskeana was conspicuously increased but those of the others were not. Fourth, by ridding the upper layer canopy, Quercus' growth rates were increased highly. Rates of DBH growth of Q. aliena, Q. mongolica and Q. dentata were increased to 53.0%, 22.9% and 8% in the experimental area, and 23.1%, 8.3% and 6.1% in the control area, respectively, during two growing seasons (from May 11, 1997 to October 27, 1998). The ratios of twig biomasses of the previous year to the next year were 100:565 in Q. aliena, 100:197 in Q. mongolica and 100:644 in Q. dentata in the experimental area. There were also growth ratios of 100:117 in Q. aliena, 100:100 in Q. mongolica and 100:42 in Q. dentata in the control area, respectively. The growth rate increases of Q. aliena and Q. dentata were thus conspicuous in twig rather than in trunk, but that of Q. mongolica was vice versa.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.29 no.1
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• pp.135-142
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• 2006

The package loading process of tile lumbering industry is an operation that after a pair of workers binds three or six lumber into a unit and cut the both ends of the lumber, carry and pack and load the weight cargo of 30-50kg. The package loading process causes lots of noise and wood dust when the lumber are cut and brings about the main cause of the musculoskeletal disorder when workers carry the heavy goods. Therefore, we developed the monolithic package loading equipment cutting both ends that is enable to improve the working method and environments of the existing package loading process. The noise and wood dust were reduced by developing the device and the main cause of shirking duties on working place was solved by preventing the musculoskeletal disorder and improving the working environments as excluding the work of carrying heavy goods.

• Journal of the Korea Safety Management & Science
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• v.10 no.2
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• pp.95-103
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• 2008

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.

• Proceedings of the Safety Management and Science Conference
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• 2008.04a
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• pp.135-147
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• 2008

The package loading process of the lumbering industry is an operation that after a pair of workers bind three or six lumbers into one unit and cut both ends of the lumbers, transports the weight cargo of 30-50kg by one meter, pack and load at a height of 1.2 meters. This package loading process causes lots of noise and wood dust when workers carry out the heavy work as the above. Therefore we developed the monolithic both ends cutting package loading equipment in order to prevent from getting musculoskeletal disease. An loading bar working system of this equipment is improved from pneumatic pressure system to oil pressure system, furnished the newly designed flow dividers, and developed the new system that a both end array is loaded identically. Also we developed the safety equipment of loading bar in order to prevent workers mistake and overload from malfunction during the package loading process. The main cause of job evasion on working place could be solved by preventing the musculoskeletal disease and improving the working environments.

• Communications for Statistical Applications and Methods
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• v.8 no.3
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• pp.739-751
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• 2001

In this paper, a sample design is studied for 2000 forestry management survey of five types forestry , tree felling, gathering of pine mushroom, growing of nut trees, growing of wild flowers, and lumbering industry. We introduce population stratification and a modified stratified cut-off sampling which deal with determination of sample size, sample allocation, and estimation of total and variance of estimator. Substitution of sample units and imputation of nonresponse units are discussed for reducing the nonsampling errors.

• The Korean Journal of Ecology
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• v.23 no.3
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• pp.223-229
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• 2000

To develop the restoration technique from urban planted forest to natural forest, sprout growth and its effects on vegetation composition in the early stage after lumbering, were studied, using only Populus albaglandulosa of the tree layer in Chungdam Park Chungdam-dong, Kangnam-gu, Seoul during the two years from 1997 to 1998. The results were as follow. After lumbering, the more basal areas of the parent stump, the more sprouts were generated. The basal area of parent stump was related more to biomass than to the number of sprouts. In the cutting area, biomasses of sprouts were 552.7 g?DW/㎡ in first year and 8.7 g?DW/㎡ in second year after lumbering. Therefore, cutting of sprouts in first year resulted in decrease of sprout production in second year. In the non-cutting area, biomass of sprouts was 657.4 g?DW/㎡ and more than that of the experiment. Especially, 2-year sprouts grew to a 304 cm height by the end of the growing season in the second year. The growing season of sprouts was from early April to early September and almost all the leaves of the sprouts remained at the end of the growing season. Specific leaf area decreased along with time elapse and plant height but the differences were not conspicuous. Therefore, it is thought that the reason why p. albaglandulosa sprouts grew fast was due to a long growing period and lower layer leaves which remained at the end of the growing season. In the cutting area of the P. albaglandulosa sprouts, there were no changes in the number of species in the shrub layer but an conspicuous increase in the herb layer. Coverage was no changes in the shrub layer but an increase in the herb layer. In the non-cutting area of P albaglandulosa sprouts, the number of species and the coverage changed a little, and the main species of the herb layer were Phytolacca americana, Eupatorium rugosum and Panicum dichotomiflorum, which are tall plant species.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.181-187
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• 2004

In case an average accumulation of the investigated area is 200$m^{3}$/ha with cutting age of 80 years applied, annual workload will be 77ha and require 5 teams; each team consisting of 5 persons, enabling stabled supply of lumbers of 15,500$m^{3}$ every year. If one cutover is less than 2ha with cutting age of 80 years applied, it's possible to protect the peculiar ecology and secure stabled labor, workload and lumbering. It may become model forest out of tropical forest management which is controversial all over the world. Of course this presupposes construction of access roads.

• Korean Journal of Plant Taxonomy
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• v.38 no.4
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• pp.583-599
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• 2008

Dokdo, small island located in the eastern end of the Korean Peninsula, has been an uninhabited island for long time due to long distance from the land. Moreover, the steep slope of volcanic tuff at Dokdo is well drained for high permeability and Dokdo has few plain areas, swamps and very thin soil layers. In this study, pollen analysis at Dokdo was attempted on the profile of organic sandy soil for the first time in Korea owing to the marine climate environment with high humidity and precipitation including snowfalls in spite of unprofitable condition geologically or geomorphologically. While many historical, political researches have been accumulated for territorial problem of Dokdo with Japan, natural scientific researches with field work are not sufficient, and few paleoecological researches have been done. As a result of pollen analysis, the ratio of the NAP(Non-Arboreal Pollen) and spore was higher than AP(Arboreal Pollen), and the vegetation change existed by showing dramatic decrease of AP at the upper layer. AP was composed of almost Pinus, and a little Alnus, Quercus, Betula, Carpinus, Picea and Ulmus. NAP was composed of Gramineae, Compositae, Chenopodiaceae Cyperaceae, Caryophyllaceae, Liliaceae, Umbelliferae, Artemisia, Lobelia, Rumex, Polygonum. Increase of the NAP such as Gramineae, Artemisia and Chenopodiaceae, they would mostly have been transported from the other areas because agricultural activity is impossible at Dokdo. While one reason of Pinus thunbergii decrease could be regarded as environmental change, the other reason would be lumbering of pine trees by human activity which is adapted to Dokdo environment.

• Proceedings of the KIEE Conference
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• 2006.11a
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• pp.63-65
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• 2006

These days, it is not easy to construct the transmission line because of the environmental association activity, a civil appeal, etc. To solve these kinds of difficulties, the program with leading-edge IT technology, such as GIS, 3 dimensions CAD, computer graphic, etc., is developed to be more transparent and objective in the design stage of the transmission line and the selection stage of the transmission line route. Comparing this program with previous methods, this program is composed of the environmental evaluation program, data producing program for analysis and selecting line route program because it is not possible to conduct those kinds of work without any help from the computer and well-developed program. To confirm the performance of the program, the result from the program and the human were compared. Therefore, the result from the program was same as the result conducted by human. In addition, the program makes the selection of the transmission line route easier by checking the mountainside, lumbering, the estimated cost of the tower construction, etc. in real-time.

• Journal of Plant Biology
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• v.5 no.2
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• pp.13-16
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• 1962

Without annual ring, the bamboo can not measured by ordinary mensuration method. Other methods yet tried failed to prove the reliability. That means, as often pointed out, that the bamboo lumbering (including forest management) is not free from being precarious. Noting the fact, this author performed a serieds of comparative observations on a group of bamboos in different stages of growth in order to find out if there is any surer mensurability. A conclusion has been reached that the external feature of joints of branch has close connection with the age of bamboo, that the joints of the third major branch counting from the ground have, as shown in the first table, the most probability, its mean being 94.3 per cent, and that those in ages of 3 to 5 have the probability of 100 per cent, showing the far greater accuracy as compared with those in older ages. The above conclusion needs to be adjusted with the following findings; 1) When observed disregarding the joint-tongue(the remainder of the preceeding year's sheath), the major branches show no better probability than the minor ones. 54 to 78 per cent of them shows no difference between them. Probability is averaged by 60 per cent. 2) When in spring the old sheaths drop away from the joints, the new ones sprout out in their places and consequently the joints present an appearance of a kind of joint-ring. But since this joint-ring does not always exactly represent the plant age, some other method must be sought after to count the age. This author noticed what is called "joint-tongue" the tongue-like part of triangle shape which remains at the base of the sheath of the fallen leaf. A fact was ascertained that when the number of the joint-ring coincides with that of the remaining joint-tongue, it exactly indicates the age of the plant.the plant.