• Journal of the Korean Wood Science and Technology
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• v.49 no.6
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• pp.550-565
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• 2021

This study's objective was to conduct species identification and tree-ring dating of wooden elements used in Mungyeong Juheulgwan of Joryeong (Gate No. 1). Of the 84 wooden elements evaluated, 76 were confirmed to be hard pines, 5 were soft pines, and 3 belonged to Abies spp. For tree-ring dating, cores of the wooden elements were collected using a drill, and ring-width plots of individual samples were constructed using the TSAP software. The results of performing tree-ring dating for the outermost ring of 59 hard pine wooden elements revealed the following 4 felling dates: summer of 1708-late fall of 1709, summer of 1792-early spring of 1794, late fall of 1838-early spring of 1840 and 1867, and early spring-fall of 1872. These felling dates were found to be consistent with those in the construction and repair records of the Annals of Joseon Dynasty, Juhulgwan Jungsugi, and those engraved on Juhulgwan Walls. It is believed that some of the wooden materials harvested at that time were stored and used since there was a difference of approximately10 years between the repair records and felling dates.

• 한국문화재보존과학회:학술대회논문집
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• 2005.11a
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• pp.300-305
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• 2005

Tree-ring chronologies can be used to date historical buildings and furniture by matching them with the chronologies of living trees or previously dated samples. Tree-ring dating gives a calender year to each tree ring and produces the felling dates of logs or woods which had been used for buildings. In Korea, several chronologies of Japanese red pine(Pinus densiflora Sieb. et Zucc.,'sonamu' in Korean), a major species for the wooden building materials, have been developed and used for dating historical buildings. Daejojeon of Changduck Palace is known to be reconstructed in A.D. 1920 after burned-out in A.D. 1917. Instead of new woods, Daejojeon was reconstructed by reusing the woods of Kyotaejeon in Kyungbok Palace. We sampled total of 26 wood samples which were replaced during the repair process of Daejojeon in 1995. Felling dates of the samples were determined by the dendrochronological crossdating method. Crossdating method employs graphic comparison of the master patterns (ring-width plots of living trees or known dates) with those of the sample chronologies of unknown dates. The cutting dates of Daejojeon woods were divided in two groups. One was the late 1860s and the other 1880s. The results confirmed that Kyotaejeon was reconstruced first in the A.D 1860s and then in late 1880s after burning out in 1876.

• Journal of Forest and Environmental Science
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• v.24 no.1
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• pp.1-14
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• 2008

Clearcutting has been the dominant harvesting method in British Columbia (representing 95% of the total area harvested annually). However forest managers are increasingly recommending the use of alternative silvicultural systems and harvest methods, including various types of partial cutting, to meet ecological and social objectives. In this study we compared harvesting productivity and harvesting costs between treatments through detailed and shift level time studies in 300-350 year-old Interior Cedar-Hemlock stands in British Columbia, Canada. Recommendations for improving operational planning/layout and the implementation of clearcut and partial cutting silvicultural systems were made. Harvesting costs varied in the ground-based clearcut treatments from $10.95/$m^3$ - $15.96/$m^3$ and $16.09/$m^3$ - $16.93/$m^3$ in the group selection treatments. The ground-based group retention treatment had a cost of $13.39/$m^3$, while the cable clearcut had a cost of $15.70/$m^3$. An understanding of the traditional and alternative wood products that could be derived from the harvested timber was imperative to increasing the amount of merchantable volume and reducing the corresponding harvesting costs. Stand damage was greatest in the group selection treatments; however, mechanized felling showed an increase in stand damage over manual felling while grapple skidding showed a decrease in skidding damage compared to line skidding.

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.679-681
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• 2005

The materials for transmission line construction were transported by road which opened in mountainous areas until the mid 1990s, However, from the mid 1990s, as social interest in the environment standard increases, a cable way and helicopter transport methods of construction have been applied to minimize damage to the environment and to build an environmental friendly system. The current cable way method is a single cable way system which has a lower section base to load materials into a carriage and carry them to the tower construction site by use of an engine and a main rope. Then the carriage lowers itself via a slope between the tower construction site and the lower section base. The single cable way system has the demerits of site acquisition for the lower section base, forest felling when installing the wire rope, and it is not applicable to a even topology Also it has to be installed separately at each tower site. Accordingly, to carry materials without forest felling and regardless of slope, the chain cable way system was developed to provide materials for more than two towers consecutively by use of an engine carriage and winch.

• Explosives and Blasting
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• v.39 no.2
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• pp.27-36
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• 2021

Recently, the demand for demolition for the unnecessary steel frame structure is increasing due to deterioration and unsatisfactory functional conditions and the major highlights of demolition issues. This execution case was intended to describe an application of the felling method as one about the suggested method for explosive demolition method of ore bin and coke bin facilities, which were steel frame structures. And we used the charging container for blast cutting of the steel frame structure. As a result of the explosive demolition, the ore bin and coke bin had collapsed precisely according to the estimated direction. And the explosive demolition was completed without causing any damage to surrounding facilities.

• Tunnel and Underground Space
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• v.31 no.3
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• pp.198-209
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• 2021

Recently, the demand for demolition of unnecessary steel shell structure is increasing due to deterioration and unsatisfactory functional conditions and the issue of demolition is becoming a major highlight. This execution case was intended to describe an application of the felling method, a explosive demolition method to demolish steel shell structures, for the demolition of a steel stack and steel head tank. As a result of the explosive demolition, the steel stack and steel head tank had collapsed precisely according to the estimated direction. And the explosive demolition was completed without causing any damage to surrounding facilities.

• Explosives and Blasting
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• v.40 no.2
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• pp.15-24
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• 2022

Recently, the demand of demolition for the unnecessary industrial structure is increasing due to deterioration tendency and the issue of demolition is becoming a major highlight. The restoration of the dismantled industrial site to its original natural state was currently underway. This execution case was intented to describe an application of the felling method one of the explosive demolition method to the demolition of the industrial stack. This stack was 150m high, a composite structure in which the outer wall of the stack was a reinforced concrete shell structure and internal stovepipe was a steel shell structure. As as result of the explosive demolition, the stack had collapsed precisely according to estimated direction. And the explosive demolition was completed without causing any damage to surrounding facilities.

• Explosives and Blasting
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• v.40 no.3
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• pp.66-76
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• 2022

Recently, the demand for the dismantling of old industrial complexes has been increasing, and the construction of restoring the dismantled industries to their original natural environment is underway. In this case, the felling method was applied to the explosive demolition method to dismantle a large steel frame structure in an old industrial complex. We used a charging container to cut the steel frame structure that generates a metal jet. The thickness of the thick steel structure in the blasting section was controlled by gouging which a method of digging deep groove by gas and oxygen flame or arc thermal. As a result of the explosive demolition, the steel frame structure collapsed precisely according to the estimated direction. The explosive demolition was completed without causing any damage to the surrounding facilities.

• Journal of Korean Society of Forest Science
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• v.103 no.4
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• pp.583-592
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• 2014

This study was carried out to investigate the operational time and productivity of logging operation by chain saw, yarder attached on tractor, tower-yarder, mini-truck, mini-forwarder, and chipping operations by mini-chipper, large-chipper in order to develop the efficient logging operation system for utilization of forest-biomass. As a result, the average felling and bucking time using chain saw at the site 1 and 2 was observed to be 182.7 sec/cycle and 518.5 sec/cycle respectively. The average yarding time was 202.5 sec/cycle using yarder attached on tractor and 295.1 sec/cycle using tower-yarder. The average forwarding time was 2,073 sec/cycle using mini-truck and 2,248.4 sec/cycle using mini-forwarder. The operational time of felling and bucking using chain-saw can be delayed according to the direction of fallen trees. The selection of felling direction is very important to yarding operation because the direction between width-yarding and felling are interrelated. Productivity can be improved through educating and training operators in the yarding operations. Mini-forwarder is needed to use because of higher productivity and lower cost than mini-truck. The operational productivity of felling and bucking by chain saw was $66.96m^3/man{\cdot}day$ and $43.86m^3/man{\cdot}day$ at site 1 and 2 respectively. The yarding productivity was $5.68m^3/man{\cdot}day$ by yarder attached on tractor, $10.74m^3/man{\cdot}day$ by tower-yarder. The forwarding productivity was $21.29m^3/man{\cdot}day$ by mini-truck, $28.57m^3/man{\cdot}day$ by mini-forwarder. The chipping productivity was $4.42m^3/man{\cdot}day$ by mini-chipper, $21.87m^3/man{\cdot}day$ by large-chipper.

• Journal of Korean Society of Forest Science
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• v.71 no.1
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• pp.1-8
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• 1985

In the study, the log pricing process by region and marketing agencies was surveyed in order to analyze the domestic timber marketing situation, and to propose improvements. The results obtained show that the market channel configuration for domestic timber is simple compared with that for the agricultural products. The log felling contractor is the lead agency in the stumpage market because of the lack of market information of most forest owners. However, the log assembler, who has ample funds, seized leadership in the market channel because most felling contractors, deal only with small timber quantities, and are usually short of funds. Also the variety of log scaling methods is a serious factor confusing domestic timber marketing. Therefore, the following steps are proposed; 1) the provision of market information to forest owners, 2) the institutional control of felling contractors, 3) the establishment of cooperative log collection centers, 4) the improvement of log quality.