• The Journal of Korean Academy of Prosthodontics
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• v.47 no.4
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• pp.406-415
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• 2009

Purpose: The purpose of this study was to compare the marginal fitness and fracture load of the zirconia copings according to the design with different thickness and coloration. Material and methods: The evaluation was based on 80 zirconia copings. Zirconia copings were fabricated in design with different thicknesses using CAD/CAM system (Everset, KAVO dental GmbH, Biberach, Germany). The designs of copings were divided into four groups. The first group consisted of copings with uniform thickness of 0.3 mm. The thickness in the second group was 0.3 mm on the buccal surface and 0.6 mm on the lingual surface. The third group consisted of coping with uniform thickness of 0.6 mm. The thickness in the fourth group was 0.6 mm on the buccal surface and 1mm on the lingual surface. Each group consisted of 10 colored and 10 uncolored copings. Half of the copings (40) processed with a milling system according to the specific design were sent to be given a color (A3) through saturation in special dye by a manufacturing company. Just after sintering, the marginal discrepancies of copings were measured on the buccal, lingual, mesial and distal surfaces of metal die, under a Video Microscope System (sv-35, Sometech, Seoul, Korea) at a magnification of $\times$ 100. It was remeasured after the adjusting of the inner surface. Next, all copings were luted to the metal dies using reinforced cement {GC FujiCEM (GC Corp. Tokyo, Japan)} and mounted on the testing jig in a Universal Testing Machine (Instron 4467, Norwood, MA, USA). The results were analyzed statistically using the one-way ANOVA test. Results: The obtained results were as follow: 1. The measured value of marginal discrepancy right after sintering was the greatest in the contraction of the buccal area in all groups, except for group I2. 2. There was no significant difference of marginal fitness among the groups in the colored zirconia group (P<.05). 3. When the marginal fitness among the groups in the uncolored zirconia group was considered, group II2 had the smallest marginal discrepancy. 4. When the colored and uncolored groups with the same design were compared, there was a significant difference between I1 and II1 groups. In group 2, 3, and 4, the uncolored zirconia had the greatest marginal fitness (P<.05). 5. After adjustment of inner surface, there was no significant difference in the marginal fitness in all groups when color and design of the zirconia coping were compared. 6. The fracture load of CAD/CAM zirconia copings showed significant difference in group 1, 2, 3, and 4. I4 and II4 had the strongest fracture load. 7. When groups with different color and same design were compared, all colored groups showed greater fracture load (P>.05), with no significance. Conclusion: There was difference in the marginal fitness according to the design and coloration of zirconia copings right after sintering, but it was decided that the copings may well be used clinically if the inner surface are adjusted. The copings should be thick enough for the reinforcement of fracture strength. But considering the esthetics of the visible surfaces (labial and buccal surface), the thickness of copings may be a little thin, without giving any significant effect on the fracture strength. This type of design may be considered when giving priority to preservation of tooth or esthetics.

• Tuberculosis and Respiratory Diseases
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• v.58 no.6
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• pp.590-599
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• 2005

Object : Cigarette smoking is a major cause of mucus hypersecretion, which is a pathophysiological feature of many inflammatory airway diseases. Mucins, which are an important part of the airway mucus, are synthesized from the Muc gene in airway epithelial cells. However, the signaling pathways for cigarette smoke-induced mucin synthesis are unknown. The aim of this study was to determine the signal pathway for smoking induced Muc5ac gene expression. Methods : A549 cells were cultured and transiently transfected with the Muc5ac promoter fragment. These cells were stimulated with 5% cigarette smoke extract (CSE) alone or with CSE after a pretreatment with various signal transduction pathway inhibitors (AG1478, PD98059 and SB203580). The Muc5ac promoter activity was examined using the luciferase reporter system, and the level of phosphorylated EGFR, ERK1/2, p38 MAPK and JNK were all examined using Western blot analysis. Muc5ac mRNA expression was also examined using reverse transcriptase polymerase chain reactions (RT-PCR). Results : 1. The peak level of luciferase activity of the Muc5ac promoter was observed at 5% concentration and after 3 hours of incubation with the CSE. The level of EGFR phosphorylation and the luciferase activity of the transfected cells caused by the CSE were significantly suppressed by AG1478 or PD98059 (P<0.01). 2. CSE phosphorylated ERK1/2 or p38 MAPK but not JNK. The Muc5ac mRNA expression level was increased by the CSE but that was suppressed by PD98059 or AG1478. 3. The CSE-induced phosphorylation of ERK1/2 was blocked by PD98059 and that of p38 MAPK was blocked by either PD98059 or SB203580. Either PD98059 or SB203580 suppressed the luciferase activity of the transfected cells (P<0.0001). Conclusion : The Muc5ac mRNA expression level was increased by the CSE. The increased CSE-induced transcriptional activity was mediated via EGF receptor activation, which led to ERK1/2 and p38 MAPK phosphorylation.

• Korean Journal of Food Science and Technology
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• v.14 no.4
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• pp.291-300
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• 1982

In order to develop effective and simple sanitation method for the extention of shelf-life of fresh poultry meat, the effect of sanitizers, sanitation methods and packaging materials on the extention of shelf-life of poultry meats was observed at the $4^{\circ}C$ and room temp$(10{\sim}20^{\circ}C)$. The results are summarized as follows: 1. The autochonous skin microflora of poultry, before processing, were believed to be removed or killed during the scalding and plucking, and exposed dermal tissue was contaminated by microorganisms from the subsequent stages of processing. 2. In the final stage of poultry processing, total viable counts of microorganisms and coliforms were averaged to $3.5{\times}10^4/cm^2$ and $400/cm^2$, respectively. 3. The refrigerated shelf-life of fresh whole poultry carcasses at $3\;to\;4^{\circ}C$ was extended to 7 to 16 days compared to control with the various treatments of some sanitizers by dipping freshly chilled carcasses for 5 min or spraying 1 liter of sanitizers per carcasses. In the case of storage at $10\;to\;15^{\circ}C$, the shelf-life of poultry carcasses was extended to one to two days by the sanitation treatments compared to control. 4. Spraying sanitation was more effective than dipping sanitation, and 5 minutes dipping and one liter spraying per carcass were enough for effective sanitation of poultry carcasses in most sanitizers. 5. The packaging with an oxygen impermeable polyvinylidene chloride extended the shelf-life to 10 days and 5 days with polyethylene compared to control. When poultry carcasses were sanitized by continuous spraying with one liter of 30 ppm of chlorine and another one liter of 5% of potassium sorbate, packaged with polyvinylidene chlorlde were extended to about 30 days compared to control.

• Journal of Food Hygiene and Safety
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• v.27 no.4
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• pp.375-387
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• 2012

The objective of this study is investigation of contamination levels and assessment of health risk effects of heavy metals in herbal pills. 31 Items and 93 samples were obtained for this investigation from major herbal medicine producing areas, herbal markets and on-line supermarkets from Jan to Jun in 2010. Inductively coupled plasma mass spectrometer method was conducted for the quantitative analysis of Pb, Cd and As. In addition, the mercury analyzer system was conducted for that of Hg without sample digestion. The average contents of heavy metals in samples were as follows : 0.87 mg/kg for Pb, 0.08 mg/kg for Cd, 2.87 mg/kg for As and 0.16 mg/kg for Hg, respectively. In addition, the average contents of heavy metals in different parts of plants, including cortex, fructus, herba, radix, seed, algae and others were 0.63 mg/kg, 3.94 mg/kg, 1.42 mg/kg, 1.05 mg/kg, 0.16 mg/kg, 22.31 mg/kg and 10.17 mg/kg, respectively. After the estimations of dietary exposure, the acceptable daily intake (ADI), the average daily dose (ADD), the provisional tolerable weekly intake (PTWI) and the relative hazard of heavy metals were evaluated. As the results, the relative hazards compared to PTWI in samples were below the recommended standard of JECFA as Pb 3.1%, Cd 0.9%, Hg 0.5%. Cancer risks through slope factor (SF) by Ministry of Environment Republic Korea and Environmental Protection Agency was $4.24{\times}10^{-7}$ for Pb and $3.38{\times}10^{-4}$ for As (assuming that the total arsenic content was equal to the inorganic arsenic). Based on our results, possible Pb-induced cancer risks in herbal pills according to parts used including cortex, fructus, herba, radix, seed, algae and others were $1.95{\times}10^{-7}$, $1.45{\times}10^{-6}$, $2.14{\times}10^{-7}$, $6.27{\times}10^{-7}$, $1.99{\times}10^{-8}$, $3.61{\times}10^{-7}$ and $9.64{\times}10^{-8}$, respectively. Possible As-induced cancer risks in herbal pills by parts used including cortex, fructus, herba, radix, seed, algae and others were $1.54{\times}10^{-5}$, $7.24{\times}10^{-5}$, $1.23{\times}10^{-4}$, $2.02{\times}10^{-5}$, $3.25{\times}10^{-6}$, $2.18{\times}10^{-3}$ and $5.67{\times}10^{-6}$ respectively. Taken together, these results indicate that the majority of samples except for some samples with relative high contents of heavy metals were safe.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.392-400
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• 2007

This experiment was conducted to evaluate effects of various periods of rye silage feeding on the growth performance, blood characteristics, and carcass quality of finishing pigs. A total of sixteen [($Landrace{\times}Yorkshire{\times}Duroc$)] pigs (90.26 kg in average initial body weight) were tested in individual cages for a 30 day period. Dietary treatments included 1) CON (basal diet), 2) S10 (basal diet for 20 days and 3% rye silage for 10 days) 3) S20 (basal diet for 10 days and 3% rye silage for 20 days) and 4) S30 (3% rye silage for 30 days). There were no significant differences in the ADG and gain/feed ratio among the treatments(p>0.05), however the ADFI was higher in pigs fed the CON diet than with pigs fed diets with rye silage (p<0.05). The DM digestibility was higher with the S20 diet than with the S30 diet (p<0.05). With regard to blood characteristics, pigs fed rye silage had a significantly reduced cortisol concentration compared to pigs fed the CON diet (p<0.05). The backfat thickness was higher with the CON diet than with the S20 or S30 diets (p<0.05). Regarding the fatty acid contents of the leans, the C18:0 and total SFA were significantly higher with the CON diet than with the other diets (p<0.05). However, the C18:1n9, total MUFA and UFA/SFA levels were significantly lower with the CON diet than the other diets (p<0.05). Regarding the fatty acid contents of fat, the levels of C18:1n9 and MUFA were similar with the S20 and S30 diets, however, these levels were higher than with the CON or S10 diets (p<0.05). In conclusion, feed intake and DM digestibility were affected by rye silage, and the cortisol concentration, backfat thickness and fatty acid composition of pork were positively affected by feeding pigs rye silage.

• Korean Journal of Heritage: History & Science
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• v.44 no.1
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• pp.196-221
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• 2011

The Royal Private Shrines or the Samyo(私廟), were dedicated to members of Choseon's royal family who could not be enshrined at the (official) Royal Ancestral Shrine, the Jongmyo(宗廟). The Samyo were constructed at the national level and were systematically managed as such. Because these private Shrines were dedicated to those who couldn't belong to the Jongmyo but were still very important, such as the ruling king's biological father or mother. The details of all royal constructions were included in the State Event Manuals, and with them, the two-dimensional layouts of the Samyo also. From the remaining "Hyunsa-gung Private Tomb Construction Layout Record(顯思宮別廟營建都監儀軌)" of 1824, which is the construction record of Gyeongwoo-gung Shrine(景祐宮) dedicated to Subin, the mother of King Sunjo(純祖), it became possible to investigate the so far unknown "The Painting of Gyeongwoo-gung Shrine", in terms of the year produced, materials used and other situational contexts. The investigation revealed that the "The Painting of Gyeongwoo-gung Shrine" is actually the "Hyunsa-gung Private Tomb Layout" produced by the Royal Construction Bureau. The bureau painted this to build Hyunsa-gung Private Shrine in a separately prepared site outside the court in 1824, according to the royal verdict to close down and move the temporary shrine inside the courtyard dedicated to Subin who had passed away in 1822. As the Construction Bureau must have also produced the Gyeongwoo-gung Shrine Layout, the painter(s) of this layout should exist among the official artists listed in the State Event Manual, but sadly, as their paintings have not survived to this day, we cannot compare their painting styles. The biggest stylistic character of the Painting of Gyeongwoo-gung Shrine is its perfect diagonal composition method and detailed and neat portrayalof the many palace buildings, just as seen in Donggwoldo(東闕圖, Painting of a panoramic view for Changdeokgung and Changgyeonggung Palaces). A well-perceiving architectural painting employs a specific point of view chosen to fit the purpose of the painting, or it can opt to the multi-viewpoint. Korean traditional architectural paintings in early ages utilized the diagonal composition method, the bird-eye viewpoint, or the multi-viewpoint. By the 18th century, detailed but also artistic architectural paintings utilizing the diagonal method are observed. In the early 19th century, the peak of such techniques is exhibited in Donggwoldo(Painting of a panoramic view for Changdeokgung and Changgyeonggung Palaces). From the perfect diagonal composition method employed and the details of the palace buildings numbering almost two hundreds, we can determine that the Painting of Gyeongwoo-gung Shrine also belongs to the same category of the highly technical architectural paintings as Donggwoldo(Painting of a panoramic view for Changdeokgung and Changgyeonggung Palaces). We can also confirm this hypothesis by comparing the painting techniques employed in these two paintings in detailthe way trees and houses are depicted, and the way ground texture is expressed, etc. The unique characteristic of the Painting of Gyeongwoo-gung Shrine is, however, that the area surrounding the central shrine building(正堂), the most important area of the shrine, is drawn using not the diagonal method but the bird-eye viewpoint with the buildings lying flat on both the left and right sides, just as seen in the "Buildings Below the Central Shrine(正堂以下諸處)" in the State Event Manual's Painting Method section. The same viewpoint method is discovered in some other concurrent paintings of common residential buildings, so it is not certain that this particular viewpoint had been a distinctive feature for shrine paintings in general. On the other hand, when the diagonalmethod pointing to the left direction is chosen, the top-left and bottom-right sections of the painting become inevitably empty. This has been the case for the Painting of Gyeongwoo-gung Shrine, but in contrast, Donggwoldo shows perfect screen composition with these empty margins filled up with different types of trees and other objects. Such difference is consistent with the different situational contexts of these two paintings: the Painting of Gyeongwoo-gung Shrine is a simple single-sheet painting, while Donggwoldo is a perfected work of painting book given an official title. Therefore, if Donggwoldo was produced to fulfill the role of depiction and documentation as well as the aesthetic purpose, contrastingly, the Painting of Gyeongwoo-gung Shrine only served the purpose of copying the circumstances of the architecture and projecting them onto the painting.

• Journal of the Korean Wood Science and Technology
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• v.10 no.3
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• pp.13-44
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• 1982

1. Since long time ago, it has been talked about that soaking wood into water for a long time would be profitable for the decreasing of defects such as checking, cupping and bow due to the undue-shrinking and swelling. There are, however, no any actual data providing this fact definitly, although there are some guesses that water soluble extractives might effect on this problem. On the other hand, this is a few work which has been done about the effect of water soluble extractives upon the some physical properties of wood and that it might be related to the above mentioned problem. If man does account for that whether soaking wood into water for a long time would be profitable for the decreasing of defects due to the undue-shrinking and swelling in comparison with unsoaking wood or not, it may bring a great contribution on the reasonable uses of wood. To account for the effect of water soluble extractives upon physical properties of wood, this study has been made at the wood technology laboratory, School of Forestry, Yale university, under competent guidance of Dr. F. F. Wangaard, with the following three different species which had been provided at the same laboratory. 1. Pinus strobus 2. Quercus borealis 3. Hymenaea courbaril 2. The physical properties investigated in this study are as follows. a. Equilibrium moisture content at different relative humidity conditions. b. Shrinkage value from gre condition to different relative humidity conditions and oven dry condition. c. Swelling value from oven dry condition to different relative humidity conditions. d. Specific gravity 3. In order to investigate the effect of water soluble extractives upon physical properties of wood, the experiment has been carried out with two differently treated specimens, that is, one has been treated into water and the other into sugar solution, and with controlled specimens. 4. The quantity of water soluble extractives of each species and the group of chemical compounds in the extracted liquid from each species have shown in Table 36. Between species, there is some difference in quantity of extractives and group of chemical compounds. 5. In the case of equilibrium moisture contents at different relative humidity condition, (a) Except the desorption case at 80% R. H. C. (Relative Humidity Condition), there is a definite line between untreated specimens and treated specimens that is, untreated specimens hold water more than treated specimens at the same R.H.C. (b) The specimens treated into sugar solution have shown almost the same tendency in results compared with the untreated specimens. (c) Between species, there is no any definite relation in equilibrium moisture content each other, however E. M. C. in heartwood of pine is lesser than in sapwood. This might cause from the difference of wood anatomical structure. 6. In the case of shrinkage, (a) The shrinkage value of the treated specimen into water is more than that of the untreated specimens, except anyone case of heartwood of pine at 80% R. H. C. (b) The shrinkage value of treated specimens in the sugar solution is less than that of the others and has almost the same tendency to the untreated specimens. It would mean that the penetration of some sugar into the wood can decrease the shrinkage value of wood. (c) Between species, the shrinkage value of heartwood of pine is less than sapwood of the same, shrinkage value of oak is the largest, Hymenaea is lesser than oak and more than pine. (d) Directional difference of shrinkage value through all species can also see as other all kind of species previously tested. (e) There is a definite relation in between the difference of shrinkage value of treated and untreated specimens and amount of extractives, that is, increasing extractives gives increasing the difference of shrinkage value between treated and untreated specimens. 7. In the case of swelling, (a) The swelling value of treated specimens is greater than that of the untreated specimens through all cases. (b) In comparison with the tangential direction and radial direction, the swelling value of tangential direction is larger than that of radial direction in the same species. (c) Between species, the largest one in swelling values is oak and the smallest pine heartwood, there are also a tendency that species which shrink more swell also more and, on the contrary, species which shrink lesser swell also lesser than the others. 8. In the case of specific gravity, (a) The specific gravity of the treated specimens is larger than that of untreated specimens. This reversed value between treated and untreated specimens has been resulted from the volume of specimen of oven dry condition. (b) Between species, there are differences, that is, the specific gravity of Hymenaea is the largest one and the sapwood of pine is the smallest. 9. Through this investigation, it has been concluded that soaking wood into plain water before use without any special consideration may bring more hastful results than unsoaking for use of wood. However soaking wood into the some specially provided solutions such as salt water or inorganic matter may be dissolved in it, can be profitable for the decreasing shrinkage and swelling, checking, shaking and bow etc. if soaking wood into plain water might bring the decreasing defects, it might come from even shrinking and swelling through all dimension.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.6
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• pp.934-947
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• 2011

The purpose of this study is to analyze products for good taste and convenience, which become an engine to constantly create customers. In addition, this study is aimed at investigating the relationship between the selective attributes of Home Meal Replacement, the perceived utilitarian value, and the repurchase intention, and drawing new suggestions on the Home Meal Replacement market from a new marketing perspective. Based on a total of 215 samples, this study reviewed the reliability and fitness of the research model and verified a total of 5 hypothesized using the Amos program. The result of study modeling was GFI=0.905, AGFI=0.849, NFI=0.889, CFI=0.945, and RMR=0.0.092 at the level of $x^2$=230.22 (df=126, p<0.001). First, the food quality (${\beta}$=0.221), convenience (${\beta}$=0.334), packing (${\beta}$=0.278), and employee service (${\beta}$=0.204) of home meal replacement consideration attributes had a positive (+) influence on perceived utilitarian value. Second, perceived utilitarian value (${\beta}$=0.584) had a positive (+) influence on repurchase intention. The factors to differentiate one company from other competitors in terms of the utilitarian value are the quality of food, convenience, wrapping, and services by employees. This study has illustrated the need to focus on the development of a premium menu to compete with other companies and to continue to research and develop nutritious foods that are easy to cook. Moreover, the key factors to have a distinct and constant competitive edge over other companies are the alleviation of consumer anxiety over wrapping container materials, the development of more designs, and the accumulation of service know-how. Therefore, it is necessary for a company to strongly develop the key factors based on its resources as a core capability.

• Journal of Korean Society of Forest Science
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• v.29 no.1
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• pp.20-53
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• 1976

For the purpose of detecting the capability of the trees to resist air pollution and of determining the tree species best suited for purification of polluted air, particularly with regard to $SO_2$ contamination, six following ornamental tree species were selected as experimental materials: i.e., Hibiscus syriacus L., Ginkgo biloba L., Forsythia koreana Nak., Syringa dilatata Nak., Larix leptolepis Gordon, and Pinus rigida Miller. The susceptiblities of the trees were observed and analyzed on the basis of area ratio of smoke injury spots to the total leaf area. The results of the experiments are as follows: I. The Susceptibilities to Sulfur Dioxide. (1) The decreasing order of tolerance to $SO_2$ by species was as follows: 1. Hibiscus syriacus 2. Ginkgo biloba, 3. Forsythia koreana, 4. Syringa dilatata, 5. Larix leptolepis, and 6. Pinus rigida. In general, Hibiscus syriacus and Ginkgo biloba can be grouped as the most resistant and Larix leptolepis and Pinus rigida as the least resistant and Forsythia koreana and Syringa dilatata as of intermediate resistance. (2) The sulfur content of the leaves treated by $SO_2$ increased in proportion to the increase of the concentration of the fumigation. The content in the coniferous species proved to be less than that of the broad-leaved species, but Ginkgo biloba proved to contain as much sulfur as broad-leaved species. (3) The earlier-stage leaves fumigated in June with the $SO_2$ concentration up-to-l-ppm showed that sulfur content increases in proportion to the increase of the concentration of the fumigation, but the difference between concentration was not so significant. (4) The later-stage leaves fumigated in October showed higher sulfur content than the earlier stage leaves, and a wider range of difference in sulfur content was detected among different concentrations. The limit of fumigation resulting in culmination of sulfur absoption in broad-leaved species, such as Syringa dilatata, Hibiscus syriacus, and Forsythia koreana proved to be around 0.6 ppm. (5) Due to the sprouting ability and the adventitious bud formation, the recovery from $SO_2$ fumigation was prominent in Hibiscus syriacus, Syringa dilatata, and Forsythia koreana. (6) The differences in the smoke spot color were recognized by species: namely, dirt-brown in Syringa dilatata, brilliant yellowish-brown in Pinus rigida and Ginkgo biloba, whitish-yellow in Hibiscus syriacus and reddish-brown in Forsythia koreana. (7) The leaf margins proved to be most susceptible, and the leaf bases of the mid-rib most tolerant. In both Ginkgo biloba and Larix leptolepis, the younger leaves were more resistant to $SO_2$ than the older ones. II. The ulfur Content of the Leaves of the Ornamental Trees Growing in the City of Seoul. (1) The sulfur contents in the leaves of the Seoul City ornamental trees showed a remarkably higher value than those of the leaves in the non-polluted areas. The sulfur content of the leaves in the non-polluted area proved to be in the following descending order: Salix pseudo-lasiogyne Leveille, Ginkgo biloba L., Alianthus altissima swingle, Platanus orientalis L., and Populus deltoides Marsh. (2) In respect to the sulfur contents in the leaves of the ornamental trees in the city of Seoul, the air pollution proved to be the worst in the areas of Seoul Railroad Station, the Ahyun Pass, and the Entrance to Ewha Womans University. The areas of Deogsu Palace, Gyeongbog Palace, Changdeog Palace, Changgyeong Park and the Hyehwa Intersection were least polluted, and the areas of the East Gate, the Ulchi Intersection and the Seodaemun Intersection are in the intermediate state.

• Journal of Korean Society of Forest Science
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• v.25 no.1
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• pp.13-47
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• 1975

Among the many species of bamboo, it is well known that the dwarf-type is widely distributed in the tropical regions, and the slender type in temperated zone. In the temperated zone the trees have extensively differentiated into one hundred species in 50 genera. In many oriental countries, the bamboo wood is being used as a material for construction and for the manufacture of technical instruments. The bamboo shoot is also regarded as a good and delicious edible resource. Moreover, recent medical investigation verifies that the sap of certain species of the bamboo is an antibiotic effect against cancer. Fortunately, it is very easy to propagate the bamboo trees by using cutting from southeastern Asian countries. This important resource can further be used as a significant source of pulp, which is becoming increasingly important. The classification system of this significant resource has not been completely established to date, even though its importance has been emphasized. Initiated by Canlevon Linne in the 18th century, a classification method concerning the morphological characteristics of flowers was the first step in developing a classification. But it was not an easy task to accomplish, because this type of classification system is based on the sexual organs in bamboo trees. Because the bamboo has a long life cycle of 60-120 years and classification according to this method was very difficult as the materials for the classification are not abundant and some species have changed, even though many references related to the morphological classification of bamboo trees are available nowadays. So, the certification of bamboo trees according to the morphological classification system is not reasonable for us. Consequently, the classification system of bamboo trees on the basis of endomorphological characteristics was initiated by Chinese-born Liese. And classification method based on the morphological characteristics of the vascular bundle was developed by Grosser. These classification methods are fundamentally related to Holltum's classification method, which stressed the morphology of the ovary. The author investigated to re-establish a new classification method based on the vascular sheath. Twenty-six species in 11 genera which originated from Formosa where used in the study. The results obtained from the investigation were somewhat coordinated with those of Crosser. Many difficulties were found in distinguishing the species of Bambusa and Dendrocalamus. These two species were critically differentiated under the new classification system, which is based on the existence of a separated vascular bundle sheath in the bamboo. According to these results, it is recommended that Babusa divided into two groups by placing it into either subspecies or the lower categories. This recommendation is supported by the observation that the evolutional pattern of the bamboo thunk which is from outward to inward. It is also supported by the viewpoint that the fundamental hypothesis in evolution is from simple to complex. There remained many problems to be solved through more critical examination by comparing the results to those of the classification based on the sexual organs method. The author observed the figure of the cross-sectional area of vascular trunk of bamboo tree and compared the results with those of Grosser and Liese, i.e. A, $B_1$, $B_2$, C, and D groups in classification. Group A and $B_2$ were in accordance with the results of those scholars, while group D showed many differences, Grosser and Liese divided bamboo into "g" type and "h" type according to the vascular bundle type; and they included Dendrocalamus and Bambusa in Group D without considering the type of vascular bundle sheath. However, the results obtained by the author showed that Dendrocalamus and Bambusa are differentiated from each other. By considering another group, "i" identified according to the existence of separated vascular bundle sheath. Bambusa showed to have a separated vascular bundle sheath while Dendrocalamus does not have a separated vascular bundle sheath. Moreover, Bambusa showed peculiar characteristics in the figure of vascular development, i.e., one with an inward vascular bundle sheath and the other with a bivascular bundle sheath (inward and outward). In conclusion, the bamboo species used in this experiment were classified in group D, without any separated vascular bundle sheath, and in group E, with a vascular bundle sheath. Group E was divided into two groups, i.e., and group $E_1$, with bivascular sheath, and group $E_2$, with only an inward vascular sheath. Therefore, the Bambusa in group D as described by Grosser and Liese was included in group E. Dendrocalamus seemed to be the middle group between group $E_l$ and group $E_2$ under this classification system which is summarized as follows: Phyllostachys-type: Group A - Phyllostachys, Chymonobambus, Arundinaria, Pseudosasa, Pleioblastus, Yashania Pome-type: Group $B_2$ - Schizostachyum, Melocanna Hemp-type: Group D - Dendrocalamu Bambu-type: Group $E_1$ - Bambusa ghi.