• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.608-611
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• 2002

We developed low resistance drum that is used in sawdust machine in this research. The existent drum have two dimensional cutting form(orthogonal cutting) when see cutting pattern of saw cutter and wood, cutting resistance is big and cutting power is cost much, and also, vibration happens extremely. To improve this shortcoming, we developed helical type low cutting resistance drum for three dimensional cutting possible, decreased vibration and cutting resistance of sawdust machine, and improve productivity and sawdust ventilation. Also, a developed drum is mounting in sawdust machine, it is sold by product.

• Journal of the Korean Society of Safety
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• v.22 no.3 s.81
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• pp.13-21
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• 2007

Personal and static sampling for formaldehyde, wood dust and noise monitoring, in accordance to the equipment running on the day, were carried out throughout wood panel manufacturing process. Even though the exposure level of formaldehyde and wood dust were below than exposure criteria, but the personal protective equipment(PPE) for those should be worn to everyone in the process because of its potential characteristics like carcinogenicity. Also a few local air extraction system above the cutting, grinding sections and organic blending room should be required. Most of the exposures of noise exposure were exceeded permitted exposure criteria, in case of Hopper operators, exposed to maximally 94dB(A) as LAeq 8hr, therefore active controls like PPE, monitoring, isolation etc. are necessary. The main sources of noise were caused on compressed air of the machinery, radio sound and operation noise like running machines, conveying, cutting, sawing, moving vehicles, storing and so on. For the comparison of control criteria in each country, the permitted exposure standards for above hazardous materials and noise in Korea, ACGIH and Australia were discussed. We have recognized that the Korean criteria should be discussed urgently to give the right information to employee and modified, if it is necessary.

• Journal of the Korean Society of Industry Convergence
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• v.7 no.4
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• pp.419-424
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• 2004

In order to increase the efficiency of the sawdust machine, the helical type drums with an oblique cutting condition (3D) were developed. The preexisting drums have an orthogonal cutting condition (2D) considering of a saw cutter and a wood cutting pattern. Unfortunately, the disadvantages of this type drum are the big cutting resistance, the high cost of a cutting power and the extreme occurrence of a vibration. To improve this shortcoming, the helical type drum with an oblique cutting condition was developed. Therefore, this type drum decreased the vibration and the cutting resistance of the sawdust machine, and also improved the productivity of 30% or more and the porosity of the sawdust.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.5
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• pp.135-140
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• 2013

Ultrasonic cutting is a kind of eco-technique and cost-effective technique to be used for cutting of various materials such as baked product, fresh/frozen food, rubber, textile, wood, bone, etc. The performance of ultrasonic cutting is affected by design of cutting horn and cutting conditions. Specially the design of horn to resonate at the longitudinal direction is most important. To analyze the problems from which cracking and noise are often generated with conventional cutting horn, FEA is carried out, and then improved cutting horn which can reduce maximum stress and stress concentration is designed. Vibration characteristics, resonant frequency, gain, and amplitude uniformity of the cutting horn designed optimally are evaluated through FFT analysis and compared with those of conventional cutting horn.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.88-92
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• 2004

We developed a helical type drum with an oblique cutting condition for sawdust machine. The existing drum has an orthogonal cutting(2D) condition considering of saw cutter and wood cutting pattern. Additional disadvantage of this type include big cutting resistance, high cost of cutting power and extreme occurrence of vibrations. To improve this shortcoming, we developed a helical type drum with an oblique cutting(3D) condition, therefore, this type drum decreased the vibration and cutting resistance of sawdust machine, and also improved productivity and sawdust porosity.

• Journal of architectural history
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• v.15 no.2
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• pp.23-38
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• 2006

During the repair and restoration of the Daewoongjeon Hall of Youngguksa Temple, species identification and tree-ring dating for both present wood elements and charred ones excavated under the Hall, were conducted. The species of 74 wood elements of Daewoongjeon Hall, were identified as Pinus densiflora Sieb. et Zucc. and only 1 was identified as exotic Pinus species. The latter wood, which was used in the laths, seems to have been replaced during past repairs. Many documentary records and various artifacts pertaining to Youngguksa Temple are being excavated, but none described precisely the construction date of the present Daewoongjeon Hall. Also, from beneath the Daewoongjeon Hall, cornerstone and foundation of previous building and several charred wood elements were excavated. In comparing the direction of the stone columns of foundation of the previous structure and the existing Daewoongjeon Hall, the previous structure was rotated in an angle of approximately $15^{\circ}$. Therefore, in order to find the association of the previous structure with the present Daewoongjeon Hall, tree-ring dating was conducted. The dating of 41 original timbers and 14 roof-filling timbers of the present construction elements revealed that the last annual ring was of A. D. 1703 with complete latewood, indicating that those woods was cut some time between the autumn of 1703 and spring of 1704, and the building was erected in 1704 when we assume no period of wood storage. The year of the last annual ring of the charred elements, which were excavated from beneath the Daewoongjeon Hall, was analyzed as 1674. The cutting year of the woods used for the present building began in 1698, therefore, it can be presumed that the Daewoongjeon Hall before the fire was a structure that was elected shortly after 1674 and that a catastrophic fire occurred some time between 1674 and 1698.

• The Korea Journal of Herbology
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• v.26 no.2
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• pp.11-15
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• 2011

Objectives : In the present study, the contents of cinnamic acid and cinnamaldehyde in three different parts of Cinnamomi Ramulus (CR) (the whole body, the bark part, and the wood part) was evaluated using UPLC (ultra performance liquid chromatography) in order to investigate a suitable cutting method. Methods : Analysis was performed on SMART LC with UV detector. Reference compounds were separated on Inertsil ODS-4 column ($2.1mm{\times}50mm$, $3{\mu}m$, GL Science, Japan) using isolation elution with water and acetonitrile each containing acetic acid at a flow rate of $500{\mu}L/min$. Additionally, samples of CR were purchased from pharmacy of medicinal herb. Results : The correlation coefficients of the cinnamic acid and cinnamaldehyde levels showed good linearity ($r^2{\geq}0.9999$) over the linear ranges. Furthermore, the bark part exhibited higher concentration levels of reference compounds than the wood part in all samples. In addition the bark exfoliation rates in oblique and perpendicular-long cut samples of CR were lower than the perpendicular-short cut samples. Conclusions : These results suggested that the optimal cutting method would be able to reduce the bark exfoliation. Therefore, the oblique or perpendicular-long cutting method is considered to be a better cutting type than the perpendicular-short cutting method.

• Journal of the Korean Wood Science and Technology
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• v.2 no.1
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• pp.3-18
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• 1974

The exports of plywood are increasing annually and it has ranked first in the world market because of the high quality product and manufactured using mordern techniques. However, it is known that the exports of the other wood products, except plywood, is inactive because of their low quality. Accordingly, to increase the exports of various wood products investigations were carried out on kiln drying techniques to improve the quality of the wood. Wet wood should be kiln dried before use to prevent various drying defects such as distortion, shrinkage etc., which would develop after processing,:and also wet wood is not suitable for cutting, gluing and finishing. Therefore, the kiln drying properties of lumber from such species as oak, ramin and meranti which are used in large quantity for manufacturing exporting wood products have been studied. The results of the research are summarized as follows. (1) The end checks and the time for drying from initial moisture content of about 40 percent to 5 percent moisture content in ovendry were investigated as follows: (2) The kiln dried results, for 30mm stock, which are presented by using kiln schedule table 3 are as follows: (3) The kiln schedules for ramin, meranti and oak are given respectively as follows: Ramin kiln schedule: Table 17 and Table 18. Meranti schedule : Table 12. Oak schedule : Table 15.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2005.11a
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• pp.323-326
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• 2005

This study aims to show the growing popularity in the use of wood in new residential construction and improvements to existing housing throughout Asia. Residents want wood in their house and we also have the problem to reduce carbon dioxide which we can solve by using wood. If well implemented in construction, we can expect Kyoto protocol reduce the average global temperature by 0.02$^{\circ}$C or even up to 0.28$^{\circ}$C by the year 2050. A survey of Korean and Japanese people was conducted targeting unique preferences that may exist between these two Nations. Initial findings showed that residents preferred wood in their homes and reductions in carbon dioxide was also a factor. It is important for architects and those interested in using wood to understand that there are many advantages to using wood materials for construction. From this point of view using wood to can produce appreciable effects such as cutting house maintenance costs, creating a natural home design, and building in a manner that is friendlier on the environment.

• Journal of the Korea Furniture Society
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• v.20 no.2
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• pp.136-142
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• 2009

Hoein Hyanggyo is a confucian shrine at Hoein, Boeungun, Chungbuk, Korea. Using tree rings, we dated its lecture hall, Myengryundang which is a two-storied wooden structure with half-gabled and half-hipped roof. The woods of Myengryundang consisted mainly of lard pine (probably, Pinus densiflora). We collected 27 samples (4 columns, 2 beams, 5 purlins, 4 capitals, 8 floor frames/boards and 4 others). The results indicated that the major cutting year was A.D. 1702. This date helped to correct the miswritten Chinese-calender date which was recorded in the document for the framework-raising ceremony.