• Journal of the Korean Wood Science and Technology
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• v.13 no.4
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• pp.3-57
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• 1985

This research was conducted to examine the feasibility of developing fire retardant particleboard and complyboard. Particleboard were manufactured using meranti particle(Shorea spp.)made with Pallmann chipper, and complyboard meranti particle and apitong veneer (Dipterocarpus spp.). Particles were passed through 4mm (6 mesh) and retained on 1mm (25 mesh). Urea formaldehyde resin was added 10 percent on ovendry weight of particle. Face veneer for complyboard was 0.9, 1.6 and 2.3mm in thickness and spread with 36 g/(30.48 cm)$^2$ glue on one side. Veneers were soaked with 10 percent solution of five fire retardant chemicals (diammonium phosphate, ammonium sulfate, monoammonium phosphate, Pyresote and Minalith), and particles with 5, 10, 15 and 20 percent solution of five chemicals. Particleboard and complyboard were evaluated on physical and mechanical properties, and fire retardancy. The results obtained were summarized as follows. 1. Among five fire retardant chemicals treated to particleboard and complyboard, the retention of ammonium sulfate in 5 percent solution showed the lowest as 1.39 kg/(30.48 cm)$^3$ exceeding the minimum retention of 1.125 kg/(30.48 cm)$^3$ recommended by Forest Products Laboratory and Koch. 2. Particleboard and complyboard treated with diammonium phosphate showed higher modulus of rupture (MOR), modulus of elasticity (MOE), internal bond strength and screw holding power than those with the other chemicals. 3. MOR and MOE of complyboard treated with fire retardant chemicals were greater than those of fire retardant particleboard. 4. Thickness swelling of fire retardant complyboard was lower than that of fire retardant particleboard. 5. The moisture content of the boards treated with Pyresote and Minalith increased and with monoammonium phosphate reduced. 6. Fire retardant particleboard showed no ignition, and fire retardant complyboard started ignition, but time required to ignite was prolonged comparing the controlboard. Complyboard with only shell veneer treated showed ignition and lingering flame, but lingering flame time was shorter than controlboard. Complyboard with treated both core and veneer showed ignition but not lingering flame. 7. Flame length, carbonized area and weight loss were smaller than controlboard but had no significant difference among chemicals treated. 8. Temperature of unexposed surface of fire retardant particleboard was lowered with the increasing concentration of five chemicals. 9. Temperature of unexposed surface of fire retardant particleboard was lowered with the highest in Pyresote and the lowest in Minalith. 10. Temperature of unexposed surface of fire retardant complyboard was lower than that of controlboard.

• Journal of the Korean Wood Science and Technology
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• v.13 no.1
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• pp.19-62
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• 1985

This study was performed to investigate: (i) the bending processing properties of silk worm oak (Quercus acutissima Carr.) and Korean red pine (Pinus densiflora S. et Z.) by boiling and steaming treatments; (ii) the effects of interrelated factors - sapwood and heartwood, annual ring placement, softening temperature and time, moisture content. and wood defects on bending processing properties; (iii) the changing rates of bending radii after release from a tension strap, and (iv) the improving methods of bending process by treatment with chemicals. The size of specimens tested was $15{\times}15{\times}350mm$ for boiling and steaming treatments and $5{\times}10{\times}200mm$ for treatments with chemicals. The specimens were green for boiling treatments and dried to 15 percent for steaming treatments. The specimens for treatments with chemicals were soaked in saturated urea solution, 35 percent formaldehyde solution, 25 percent polyethylene glycol -400 solution, and 25 percent ammonium hydroxide solution for 5 days and immediately followed the bending process, respectively. The results obtained were as follows: 1. The internal temperature of silk worm oak and Korean red pine by boiling and steaming time was raised slowly to $30^{\circ}C$ but rapidly from $30^{\circ}C$ to $80-90^{\circ}C$ and then slowly from $80-90^{\circ}C$ to $100^{\circ}C$. 2. The softening time required to the final temperature was directly proportional to the thickness of specimen. The time required from $25^{\circ}C$ to $100^{\circ}C$ for 15mm-squared specimen was 9.6-11.2 minutes in silk worm oak and 7.6-8.1 minutes in Korean red pine. 3. The moisture content (M.C.) of specimen by steaming time was increased rapidly first 4 minutes in the both species, and moderately from 4 to 20 minutes and then slowly and constantly in silk worm oak, and moderately from 4 to 15 minutes and then slowly and constantly in Korean red pine. The M.C. of 15mm-squared specimen in 50 minutes of steaming was increased to 18.0 percent in the oak and 22.4 percent in the pine from the initial conditioned M.C. of 15 percent The rate of moisture adsorption measured was therefore faster in the pine than in the oak. 4. The mechanical properties of the both species were decreased significantly with the increase of boiling rime. The decrement by the boiling treatment for 60 minutes was measured to 36.6-45.0 percent in compressive strength, 12.5-17.5 percent in tensile strength, 31.6-40.9 percent in modulus of rupture, and 23.3-34.6 percent in modulus of elasticity. 5. The minimum bending radius (M.B.R.) of sapwood and heartwood was 60-80 mm and 90 mm in silk worm oak, and 260 - 300 mm and 280 - 300 mm in Korean red pine, respectively. Therefore, the both species showed better bending processing properties in sapwood than in heartwood. 6. The M.B.R. of edge-grained and flat-grained specimen in suk worm oak was 60-80 mm, but the M.B.R. in Korean red pine was 240-280 mm and 260-360 mm, respectively. Comparing the M.B.R. of edge-grained with flat-grained specimen, in the pine the edge-grained showed better bending processing property than the flat-grained. 7. The bending processing properties of the both species were improved by the rising of softening temperature from $40^{\circ}C$ to $100^{\circ}C$. The minimum softening temperature for bending was $90^{\circ}C$ in silk worm oak and $80^{\circ}C$ in Korean red pine, and the dependency of softening temperature for bending was therefore higher in the oak than in the pine. 8. The bending processing properties of the both species were improved by the increase of softening time as well as temperature, but even after the internal temperature of specimen reaching to the final temperature, somewhat prolonged softening was required to obtain the best plastic conditions. The minimum softening time for bending of 15 mm-squared silk worm oak and Korean red pine specimen was 15 and 10 minutes in the boiling treatment, and 30 and 20 minutes in the steaming treatment, respectively. 9. The optimum M.C. for bending of silk worm oak was 20 percent, and the M.C. above fiber saturation point rather degraded the bending processing property, whereas the optimum M.C. of Korean red pine needed to be above 30 percent. 10. The bending works in the optimum conditions obtained as seen in Table 24 showed that the M.B.R. of silk worm oak and Korean red pine was 80 mm and 240 mm in the boiling treatment, and 50 mm and 280 mm in the steaming treatment, respectively. Therefore, the bending processing property of the oak was better in the steaming than in the boiling treatment, but that of the pine better in the boiling than in the steaming treatment. 11. In the bending without a tension strap, the radio r/t of the minimum bending radius t to the thickness t of silk worm oak and Korean red pine specimen amounted to 16.0 and 21.3 in the boiling treatment, and 17.3 and 24.0 in the steaming treatment, respectively. But in the bending with a tension strap, the r/t of the oak and the pine specimen decreased to 5.3 and 16.0 in t he boiling treatment, and 3.3 and 18.7 in the steaming treatment, respectively. Therefore, the bending processing properties of the both species were significantly improved by the strap. 12. The effect of pin knot on the degradation of bending processing property was very severe in silk worm oak by side, e.g. 90 percent of the oak specimens with pin knot on the concave side were ruptured when bent to a 100 mm radius but only 10 percent of the other specimens with pin knot on the convex side were ruptured. 13. The changing rate in the bending radius of specimen bent to a 300 mm radius after 30 days of exposure to room temperature conditions was measured to 4.0-10.3 percent in the boiling treatment and 13,0-15.0 percent in the steaming treatment. Therefore, the degree of spring back after release was higher in the steaming than in the boiling treatment. And the changing rate of moisture-proofing treated specimen by expoxy resin coating was only -1.0.0 percent. 14. Formaldehyde, 35 percent solution, and 25 percent polyethylene glycol-400 solution found no effect on the plasticization of the both species, but saturated urea solution and 25 percent ammonium hydroxide solution found significant effect in comparison to non-treated specimen. But the effect of the treatment with chemicals alone was inferior to that of the steaming treatment, and the steaming treatment after the treatment with chemicals improved 10-24 percent over the bending processing property of steam-bent specimen. 15. Three plasticity coefficients - load-strain coefficient, strain coefficient, and energy coefficient - were evaluated to be appropriate for the index of bending processing property because the coefficients had highly significant correlation with the bending radius. The fitness of the coefficients as the index was good at load-strain coefficient, energy coefficient, and strain coefficient, in order.

• The Research Journal of the Costume Culture
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• v.3 no.2
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• pp.241-260
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• 1995

The Maori's traditional clothing materials, basic forms of dress, and the pattern and technique of tatoo were examined in the present study in order to deepen the appreciation of the cultural heritage of the Maori. The research method employed was the analysis of written materials. And a fild-trip was also made for the study. The study was limitted to the traditional culture of body adornment of the Maori including the clothing which is preserved and practicing by them at the present day, and the origin and the process of the historical development of those are not included in the scope of the present study. Followings are the results of the study: (1) By far the most widely used fiber for Maori clothing is abtained from what is commonly called New Zealand Flax. The fiber of kiekie(Freycinetia baueriana) and cabbage trees(Cordyline spp.) may also be used. The strong, long-lasting fiber of toi(cordyline indivisa) is used for a prestige warrior's cloak. Flat strips of ti kauka(Cordyline australi) are also used as thatch on rain cloaks. (2) Regardless of technique used, Maori weaving is always worked horizontally from left to right. Traditionally the work was suspended between two upright turuturu or weaving sticks. As the work progressed a second pair of uprights was used to keep the work off the ground. These uprights were moved forward as required. Because the weaver sat on the ground, the working edge was kept at a height that was comfortable to reach. No weaving tools are used, the wefts(aho) being manipulated by the fingers. The two main Maori weaving techniques are whatu aho patahi(single-pair twining) and whatu aho rua(double-pair twining). (3) The Maori wore two basic garments - a waist met and a cloak. The cloth of commoners were of plain manufacture, while those of people of rank were superior, sometimes being decorated with feather or dyed tags and decorated borders. Children ran more-or-less naked until puberty, being dressed only for special events. Some working dress consisted of nothing more than belts with leaves thrust under them. Chiefs and commoners usually went barefoot, using rough sandals on journeys over rough country (4) The adornment of men and women of rank was an important matter of tribal concern as it was in chiefly persons that prestige of the group was centred, The durable items of Maori persons adornment were either worn or carried. Ornaments of various kinds were draped about the neck or suspended from pierced earlobes. Combs decorated the head. Personal decorations not only enhanced the appearance of men and women, but many had protective magical function. The most evident personal ornament was the hei-tiki made of jade or other material. Maori weapons were treasured by their owners. They served on bottle and were also personal regalia. A man of rank was not fully dressed without a weapon in hand. Also weapons were essential to effective oratory. (5) No man or woman of rank went without some tattoo adornment except in extremely rare instances when a person was too sacred to have any blood shed. The untattooed were marked as beeing commoners of no social standing. This indelible mark of rank was begun, with appropriate rite and ritual, at puberty. And tattoo marked the person as being of a marriageable age. Maori tattoo was unlike most traditional tattoo in that its main line were 'engraved' on the face with deep cuts made by miniature bone chisels. The fill-in areas were not tattooed with cuts but with the multiple pricks of small bone 'combs' that only lightly penetrated the skin surface. The instrument of tattoo consisted of small pots of pumice or wood into which was placed a wetted black pigment made from burnt kauri gum, burnt vegetable caterpillars or other sooty materials. A bird bone chisel or comb set at right angles on a short wooden handle was dipped into the gigment, that a rod or stick was used to tap head of this miniature adze, causing penetration of the skin surface. Black pigment lodged under the skin took on a bluish tinge. A full made facial tattoo consisted of major spirals with smaller spirals on each side of the nose and sweeping curved lines radiating out from between the brows over the forehead and from the nose to the chin. The major patterns were cut deep, while the secondary koru patterns were lightly pricked into the skin.

• Journal of Korean Medical classics
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• v.21 no.4
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• pp.41-60
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• 2008

The acupuncture and moxibustion documentary characteristics of the "Dong-insuhyeolchimgudogyeong(銅人腧穴鍼灸圖經)" can be summarized into 5 parts such as the following. 1. The Index of Books lists the author of "Dong-indogyeong" as 'Wang-yuil(王惟一)' in some and 'Wang-yudeok(王惟德)' in others. Of these 'Wang-yudeok' is the name in the printed book and 'Yuil(惟一)' was the name it was changed into in order to make it different from the emperor Jinjong(眞宗) of the Song dynasty. Also, the sequence differs greatly among the original editions and sometimes even conflicts within itself, which makes very likely the possibility that the author of this book is not just one person, and that Wangyuil is just the main editor or screener. 2. The original printed edition of the Song(宋) dynasty has 3 volumes and the Cheonsoeng Seokgak(天聖 石刻) of the Song dynasty also has 3 volumes, but 'Hyeolsudosu(穴腧都數)', 'Sumyeongdanggyeolsik(修明堂訣式)', and 'Pichimgugyeol(避鍼灸訣)' were added to the 3rd volume. Of these three 'Pichimgugyeol(避鍼灸訣)' explains the 'Chimgupigijido(鍼灸避忌之圖)' of the 2nd volume in writing, 'Sumyeongdanggyeolsik(修明堂訣式)' explains the three human drawings from the front, side and lying down views in writing and was used to make bronze figures. 'Hyeolsudosu(穴腧都數)' was possibly used to draw acupuncture points when making bronze figures. During the Daejeong(大定) era of the Keum(金) dynasty Jinssi(陳氏) from the Pyeongsuseobang(平水書坊) revised this book and carved it into 5 volumes, and of those the 1st and 2nd volumes have characters that are very different from those of the rubbed copy of the stone carvings[石刻 拓本] from the Myeong(明) dynasty, which shows that it was taken from another book and not from the original text. The 3rd volume has added content from the stone carvings about accupuncture and moxibustion contraindication(鍼灸禁忌). During the Myeong dynasty the 3 volumes of the "Dong-indogyeong(銅人圖經)" were carved on wood based on the Jungtong Sukgan(正統 石刻), and there were many reprints with the contents that are almost all the same, but the order of the original edition were not all the same. When analyzed from many angles, the original printed copy was carved after the Jungtong(正統) of the Myung dynasty. 3. The content on transport points[輸血] in "Dong-indogyeong(銅人圖經)" comes mostly from books like "Oedae(外臺)" 'Myeongdang(明堂)', "Taepyeongseonghyebang(太平聖惠方)" 'Chimgyeong(鍼經)', "Yeongchugyeong(靈樞經)", Wangbing(王冰)'s annotation of "Somun(素問)", "Cheon-geumyobang(千金要方)" 'Chimgu(鍼灸)', and does not have much new content added by Wang-yuil(王惟一). However when Wang quotes past documents, little is summarized, some are edited and most do not have their origin indicated(the titles of other books quoted in the book are to give some supplementary explanation or are copied from another book). 4. There are many mistakes Wangyuil made in using documents and doing historical research and they can be seen in two fields. One is that he did not fix the errors of past documents, and the other is that he did not know the sequence of past documents or did not understand the meaning of the text. 5. The content Wangyuil newly added can mostly be seen in the few annotations and aneo(按語) under the original 'Geumbu(今附)'('Sinbu(新附)'). In order to see Wang's scholarly ideas and achievements we must rely on this part and the meridian entry of the transport points[輸血歸經] in the first part of the book. However we must not give credit to Wang for work that was done by former generations.

• Radiation Oncology Journal
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• v.23 no.4
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• pp.230-235
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• 2005

Purpose: To evaluate the contralateral breast dose using a virtual wedge compared with that using a Physical wedge and an open beam in a Siemens linear accelerator. Materials and Methods: The contralateral breast dose was measured using diodes placed on a humanoid phantom. Diodes were placed at 5.5 cm (position 1), 9.5 cm (position 2), and 14 cm (position 3) along the medial-lateral line from the medial edge of the treatment field. A 6-MV photon beam was used with tangential irradiation technique at 50 and 230 degrees of gantry angle. Asymmetrically collimated $17{\times}10cm$ field was used. for the first set of experiment, four treatment set-ups were used, which were an open medial beam with a 30-degree wedged lateral beam (physical and virtual wedges, respectively) and a 15-degree wedged medial beam with a 15-degree wedged lateral beam (physical and virtual wedges, respectively). The second set of experiment consists of setting with medial beam without wedge, a 15-degree wedge, and a 50-degree wedge (physical and virtual wedges, respectively). Identical monitor units were delivered. Each set of experiment was repeated for three times. Results: In the first set of experiment, the contralateral breast dose was the highest at the position 1 and decreased in order of the position 2 and 3. The contralateral breast dose was reduced with open beam on the medial side ($2.70{\pm}1.46%$) compared to medial beam with a wedge (both physical and virtual) ($3.25{\pm}1.59%$). The differences were larger with a physical wedge ($0.99{\pm}0.18%$) than a virtual wedge ($0.10{\pm}0.01%$) at all positions. The use of a virtual wedge reduced the contralateral breast dose by 0.12% to 1.20% of the proscribed dose compared to a physical wedge with same technique. In the second experiment, the contralateral breast dose decreased in order of the open beam, the virtual wedge, and the physical wedge at the position 1, and it decreased in order of a physical wedge, an open beam, and a virtual wedge at the position 2 and 3. Conclusion: The virtual wedge equipped in a Siemens linear accelerator was found to be useful in reducing dose to the contralateral breast. Our additional finding was that the surface dose distribution from the Siemens accelerator was different from a Varian accelerator.

• Journal of Korean Society of Forest Science
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• v.111 no.2
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• pp.311-318
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• 2022

We conducted this study to derive the site index, which is a criterion for the planting of Robinia pseudoacacia, a honey plant, and to investigate the diameter distribution change by derived site index. We applied the Chapman-Richards equation model to estimate the site index of the Robinia pseudoacacia stand. The site index was distributed within the range of 16-22 when the base age was 30 years. The fitness index of the site index estimation model was low, but we judged that there was no problem in the application because the residual distribution of the equation had not shifted to one side. We used the Weibull diameter distribution function to determine the diameter distribution of the Robinia pseudoacacia stand by site index. We used the mean diameter and the dominant tree height as independent variables to present the diameter distribution, and our analysis procedure was to estimate and recover the parameters of the Weibull diameter distribution function. We used the mean diameter and the dominant tree height of the Robinia pseudoacacia stand to show distribution by diameter class, and the fitness index for dbh distribution estimation was about 80.5%. As a result of schematizing the diameter distribution by site indices as a 30-year-old, we found that the higher the site index, the more the curve of the diameter distribution moved to the right. This suggests that if the plantation were to be established in a high site index stand, considering the suitable trees on the site, the growth of Robinia pseudoacacia woul d become active, and not onl y the production of wood but al so the production of honey would increase. We therefore anticipate that the site index classification table and curve of this Robinia pseudoacacia stand will become the standard for decision making in the plantation and management of this tree.

• Journal of Korean Medical classics
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• v.10
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• pp.450-493
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• 1997

Three-yum and three-yang(三陰三陽) is the change state of yum-yang(陰陽) which is caused by six gi(六氣). They mean the flow of six gi(六氣) which exist throughout the viscera, the channel(經絡), and the skin. But it is not easy to understand the meaning because the contents of the attribute of three-yum and three-yang(三陰三陽), the bolt-leaf-hanges(關闔樞) theory and large or small of gi-blood(氣血多少) which is the main clue that explain it in ${\ll}$Somun(素問)${\gg}$ and ${\ll}$Yeongchu(靈樞)${\gg}$ don't coincide with each other. I, the writer, tried to understand the uncertain meaning and the contents which are written about three points above differently in each of the books that are ${\ll}$Somun(素問)${\gg}$ and ${\ll}$Yeongchu(靈樞)${\gg}$. So, from that the course that the book, ${\ll}$Huangjenegeong(黃帝內經)${\gg}$ is handed down is so relatively simple in a wood block-printed book, that the ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$ has less wong-words than the Somun(素問) and the Yeongchu(靈樞), and from that Yangshangsun(楊上善) wrote the note in the ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$ by royal order about 100 years former than Wangbing(王氷), as making projects of Yangshangsun(楊上善)'s note and the original of the ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$ which has relation to the yum-yang(陰陽) attribute of three-yum and three-yang(三陰三陽), the bolt-leaf-hanges(關闔樞) theory, and the large or small of gi-blood(氣血多少) and researching the Yangshangsun(楊上善)'s theory. The result is summarized like this. First, wherease the order of the change of three-yum and three-yang(三陰三陽) which is explained by Yangshangsun(楊上善) consider the change of yangi(陽氣) in body most important, the order of the change gaeggi(客氣)'s three-yum and three-yang(三陰三陽) considers chungi(天氣) most important, and the order of jugi(主氣)'s three-yum and three-yang(三陰三陽) considers jigi(地氣)'s change of ohaeng(五行) most important. If the order of change three-yum and three-yang(三陰三陽) in the ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$ is considered, each of taeyang(太陽) and soyum(少陰) are expressed as the base of yum-yang(陰陽) and yangmeong(陽明) and taeyum(太陰) are expressed as the palmy days of yum-yang(陰陽), soyang(少陽) and gyolyum(厥陰) are expressed as pacemaker(樞杻) which controls the change of yum-yang(陰陽). Thus, each has something in common that is fettered by the inside and outside. In the flow of channel(經絡), taeyang(太陽) and soyum(少陰) take charge of the behind of body, yangmeong(陽明) and taeyum(太陰) take charge of the front of body and soyang(少陽) and gyolyum(厥陰) take of the side of body. Second, in Yangshangsun(楊上善)'s bolt-leaf-hanges(關闔樞) theory, three-yum(三陰) is regarded as inside, three-yang(三陽) as outside, so when bolt, leaf and hanges fulfil their duties in inside and outside, the life(life force) is thought to be revealed normally. It is impossible to understand the bolt-leaf-hanges with the conception of the inside and outside which divide three-yum and three-yang(三陰三陽) into taeyang-soyum(太陽-少陰), yangmeong-taeyum(陽明-太陰), soyang-gyolyum(少陽-厥陰) according to yum-yang(陰陽) attribute, hence it need the special conception that is taeyang(太陽)-taeyum(太陰), yangmeong(陽明)-gyolyum(厥陰), soyang(少陽)-soyum(少陰) which center on their duties in inside and outside. In the denunciation of the word open(開) and bolt(關), because Yangshangsun(楊上善) said that the duities of taeyang(太陽) and taeyum(太陰) are shutter(閉禁), bolt(關) is coincided with that significance. Third, with explaining the large or small of gi-blood(氣血多少) of three-yum and three-yang(三陰三陽), Yangshangsun(楊上善) expressed the inside and outside either in the same way or differently. Because the inside and outside is interior of body and exterior of body, it is the explanation that is noticed by the fact that the property of large or small of gi-blood(氣血多少) is either able to be same or different. In this viewpoint, if we unite the contents about large or small of gi-blood(氣血多少) of ${\ll}$Somun(素問)${\gg}$, ${\ll}$Yeongchu(靈樞)${\gg}$, we will find that the descriptions of large or small of gi-blood(氣血多少) of three-yang(三陽) in ${\ll}$Somun(素問)${\gg}$ ${\ll}$Yeongchu(靈樞)${\gg}$ correspond with the ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$, but in three-yum(三陰), the contrary presentations exit. The reason is that large or small of gi-blood(氣血多少) of three-yum(三陰) isn't only expressed as che(體) in the point of che-yong(體用), but as a point of yong(用) that is a phenomenon. As researching the original of ${\ll}$Huangjenegeongtaeso(黃帝內經太素)${\gg}$ and Yangshangsun(楊上善)'s notes as a center about three problems that are yum-yang(陰陽) attribute, the bolt-leaf-hanges(關闔樞) and large or small of gi-blood(氣血多少) of three-yum and three-yang(三陰三陽), I, the writer, tried to explain the part which is written differently or has uncertain conception in the book ${\ll}$Somun(素問)${\gg}$ and the book ${\ll}$Yeongchu(靈樞)${\gg}$, but the concrete result of the work like this will be judged according to the question how many theories are correspondent with real presence at a sickbed. Hence, the work to veryfy the theories in the future will be left as assignment.