• The Korean Journal of Ecology
• /
• v.23 no.1
• /
• pp.25-32
• /
• 2000

To analyze the relationship between climatic factors (monthly temperatures and precipitations) and the radial growths or Pinus densiflora with different topographical settings in Worak National Park, Korea, 20 stands were chosen and 10 trees were selected from each stand. After crossdating, each ring-width series was double detrended (standardized) by fitting first a negative exponential or straight regression line and secondly a 60-year cubic spline. The growth patterns coud be categorized by four groups using cluster analysis. Cluster Ⅰ stand has north aspect, but others have south or southwest aspects. Cluster Ⅰ (one), cluster Ⅱ (ten), and cluster Ⅲ (two) stands are located in lower. elevation (305∼580 m), however, cluster Ⅳ (seven) stands are located in higher elevation, mostly in 560～870 m. Cluster Ⅱ and Ⅲ stands are located at similar elevation with the same aspect, however, cluster Ⅱ stands are located on more rocky and stiff slope with shallow soil depth. The response functions were used to examine the difference in the relationships between climatic factors and tree growths among the 4 cluster chronologies. The climatic factors are not limiting the growth in the cluster Ⅰ stand as highly as in other cluster plots because of rather mesic conditions in the north slope. The precipitation in the spring appears to be the main limiting factor in the cluster Ⅱ stands. The topographical characteristics of the sites of cluster Ⅱ, shallow soil depths on the rocky slope in the south aspect at lower elevation, may enhance the sensitivity of growth to moisture stress. In cluster Ⅲ and cluster Ⅳ, winter and spring temperature prior to the growth become more important than for cluster Ⅱ. This pattern is com-mon for Pinus densiflora trees growing in higher. elevation (equation omitted 800 m) in South Korea. It nay be re-lated with preconditioning effects of temperature as the temperature decreases with increasing elevation (cluster Ⅳ) or in the valley (cluster Ⅲ). The results obtained by tree-ring analysis were digitalized by GIS and spatio-temporal information on tree-ring data and topographic setting were analyzed and displayed simultaneously. The results of this study can be used to predict the future change of Pinus densiflora ecosystem to climate change expected in central Korea.

• Journal of Forest and Environmental Science
• /
• v.28 no.4
• /
• pp.268-277
• /
• 2012

Among the domestic softwoods, technical value of Pinus koraiensis small diameter logs which have comparatively low applicability was evaluated and sensitive characteristics and physical characteristics were investigated and analyzed for examining if it can be utilized as the interior decoration material. For the sensitive characteristics of Pinus koraiensis, wood figure, wood grain, wood color and odor were evaluated and for the physical characteristics, growth-ring width and latewood percentage, abrasion, density, shrinkage, swelling, absorption, roughness and hardness were evaluated. Then, the possibility to be developed as the interior decoration material was found. As the result of evaluating sensitive characteristics and physical characteristics of domestic Pinus koraiensis, wood figure, wood grain, color and scent clearly were judged to have excellent visual factor as the interior decoration material. And, physical characteristics were also judged to be excellent, so it is judged to be developed as the interior decoration material. Therefore, as the result of various forms of design pattern with domestic Pinus koraiensis small diameter logs, several patterns of interior decoration can be developed by characteristics of each side and colors of heartwood and sapwood. And, in the future, it can be applied to furniture design or interior decoration material for the proper use. Especially, it is considered to contribute to wood applying industry through the study on the quality of domestic small diameter logs which have low applicability.

• Journal of the Korean Wood Science and Technology
• /
• v.47 no.5
• /
• pp.617-632
• /
• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.23
• /
• pp.10281-10287
• /
• 2015

Background: Development of a nanosized polymeric delivery system for erlotinib was the main objective of this research. Materials and Methods: Poly caprolactone-polyethylene glycol-polycaprolactone (PCEC) copolymers with different compositions were synthesized via ring opening polymerization. Formation of triblock copolymers was confirmed by HNMR as well as FT-IR. Erlotinib loaded nanoparticles were prepared by means of synthesized copolymers with solvent displacement method. Results: Physicochemical properties of obtained polymeric nanoparticles were dependent on composition of used copolymers. Size of particles was decreased with decreasing the PCL/PEG molar ratio in used copolymers. Encapsulation efficiency of prepared formulations was declined by decreasing their particle size. Drug release behavior from the prepared nanoparticles exhibited a sustained pattern without a burst release. From the release profiles, it can be found that erlotinib release rate from polymeric nanoparticles is decreased by increase of CL/PEG molar ratio of prepared block copolymers. Based on MTT assay results, cell growth inhibition of erlotinib has a dose and time dependent pattern. After 72 hours of exposure, the 50% inhibitory concentration (IC50) of erlotinib hydrochloride was appeared to be $14.8{\mu}M$. Conclusions: From the obtained results, it can be concluded that the prepared PCEC nanoparticles in this study might have the potential to be considered as delivery system for erlotinib.

• Korean Journal of Food Science and Technology
• /
• v.2 no.1
• /
• pp.96-103
• /
• 1970

No foods are available commercially for weanling infants except a limited amount of expensive milk products in Korea. Although the majority of infants are breast-fed, when it is not possible, rice products must usually be substituted which is not sufficient in protein. Therefore, it is urgent to develop low-cost quality protein food mixtures. In order to accomplish this purpose three food mixtures (F-S-2, F-F-3 and F-P-4), consisting of rice (37∼46%), soybean (24∼40%), FPC (3∼7%), vitamins, minerals and other food additives, are developed. The food mixtures are white to light yellow in color; dispersed readily in water with water absorption index 320; viable bacterial population, less than $10^4$ per gram; sedimentation value, 63; Bostwick consistency value, 15cm/30%; and ring test value, 23cm/30%. The products contain 22∼25% protein and ensure reasonably balanced essential amino acids for the requirement of infants compared with FAO provisional pattern, Rao's maximum growth requirements and Holt's amino acid requirements in early life. Although threonine is limiting, protein score of F-P-4 formula is 93 based on the modified FAO provisional pattern (1965). Furthermore, a 100g of the products supplies required amounts of vitamins and minerals by the recommended daily dietary allowances for infants.

• Journal of agriculture & life science
• /
• v.43 no.6
• /
• pp.7-17
• /
• 2009

The objectives of this study were to analyze vegetation type and stand structure of the red pine (Pinus densiflora) in Kangwon northern region for stable and sustainable management forests. The pine forests in study sites were classified into 3 communities, 5 groups, and 2 subgroups, total 7 vegetation units. Species with constance degree of more than 61% were P. densiflora, Quercus mongolica, Lindera obtusiloba, Spodiopogon sibiricus, Atractylodes japonica, Rhododendron mucronulatum, and Carex humilis. They were showing different characteristics by pattern according to their growing district. In the importance value (I.V.) analysis of each layer, P. densiflora showed highly in tree layer while in other layers Quercus spp. was high. Especially, young P. densiflora tree hardly appeared in the herb layer, but broad-leaved trees and shrub species showed high I.V.. Furthermore, the annual ring growth of P. densiflora was reduced while that of Q. spp. increased. According to analysis of stand structures and annual ring growths, it is considered that appropriate silvicultual practice methods should be employed to remove rival broad-leaved species for maintenance of sustainable red pine forests considering the characteristics of each stand.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1996.06a
• /
• pp.40-41
• /
• 1996

Nitridation technique has been receiving much attention for the formation of a thin nitrided buffer layer on which high quality nitride films can be formedl. Particularly, gallium nitride (GaN) has been considered as a promising material for blue-and ultraviolet-emitting devices. It can also be used for in situ formed and stable passivation layers for selective growth of $GaAs_2$. In this work, formation of a thin nitrided layer is investigated. Nitrogen electron cyclotron resonance(ECR)-plasma is employed for the formation of thin nitrided layer. The plasma source used in this work is a compact ECR plasma gun3 which is specifically designed to enhance control, and to provide in-situ monitoring of plasma parameters during plasma-assisted processing. Microwave power of 100-200 W was used to excite the plasma which was emitted from an orifice of 25 rnm in diameter. The substrate were positioned 15 em away from the orifice of plasma source. Prior to nitridation is performed, the surface of n-type (001)GaAs was exposed to hydrogen plasma for 20 min at $300{\;}^{\circ}C$ in order to eliminate a native oxide formed on GaAs surface. Change from ring to streak in RHEED pattern can be obtained through the irradiation of hydrogen plasma, indicating a clean surface. Nitridation was carried out for 5-40 min at $RT-600{\;}^{\circ}C$ in a ECR plasma-assisted molecular beam epitaxy system. Typical chamber pressure was $7.5{\times}lO^{-4}$ Torr during the nitridations at $N_2$ flow rate of 10 seem.(omitted)mitted)

• Journal of Korean Society of Forest Science
• /
• v.40 no.1
• /
• pp.1-18
• /
• 1978

Three Pinus densiflora populations as shown in location map (Fig. 1) were studied in 1977. These succeed the population numbers 10, 11 and 12 after the preceeding populations. Following the previous study methods, 20 trees were chosen from each population and the morphological characteristics such as tree forms, branching habit, needle and wood properties were investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 40 to 45. The growth performances of trees of population 10 and 11 was similar, but 12 seemed to be inferior more or less. 2. The ratios of clear bole length was 0.53 in population 12 as the highest but 0.43 for population 10 as the lowest. 3. The population 12 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown length) 1.65 though the mean branching angle indicates almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between populations as shown in Fig. 3 and 4. 5. No inter-population differences in serration density of needle was shown but significant inter and intra-population and individual differences (within population) in number of stomata rows and resin duct. 6. Population 12 shown 0.119 of resin duct index as the maximum. 7. The pattern of diameter growth, analyses based on the width of 10-year-ring segment unit (for example, the 1st segment denotes the width between pith center and 10th year ring and the 2nd one is from 11th to 20th year ring and so on.), was alike among populations as shown in Fig. 9. 8. No significant differences between population in mean summer wood percentages as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 10 and 11 however vice versa in population 12. 9. The fiber length was increased with the increase of age but no differences between populations as shown in Fig. 12.

• Journal of the Korean Geographical Society
• /
• v.30 no.1
• /
• pp.35-56
• /
• 1995

During the last two decades, Korea has achieved remarkable economic growth. In this process the nation has become urbanized and industrialized. But we have also encountered widening regional disparity, housing shortage of larger cities, transportation congestion, environmental pollution and many other problems. Rapid increasing urbanization and continuous migration toward Seoul since the late 1960s have been one of the major concerns of government. Government has sought ways to moderate the population increase in Seoul. The regulation which include new town development near Seoul and dispersion strategies of higher education and other administration and living facilities outside of Seoul havemade a great expansion of the spatial influence of Seoul city. Seoul metropolitan reaion has evolved as the most powerful center of political and economical spaces. Generally within a metropolitan region, there exists a growing mutual interdependence economically, as well as socially between a central city and its surrounding area. Seoul metropolitan region manifests itself not only as a coherent system of urbanized regions, but also as an integral part of the daily urban system. The surrounding Gyunggi province and Seoul city become closely linked both economically and functionally, constituting true functlonai urban system. This study is primarily undertaken with the purpose of delineation of the sphere of influence of Seoul city in 1990. At the time of 1985, Seoul metropolitan region was delineated according to the result of the study which was performed by Korea Research Institute for Human Settlements. Afterward, the rapid speed of metropolitanization process with dramatic increase in mobility through the provision of wider transportation system across the Capital region have evolved, resulting in the great expansion of the spatial influence of Seoul city. So this study examines the expanded area of Seoul metropolitan regin during the period of 1985-90. In order to delineate Seoul metropolitan region, the indices of urbanization and functional linkage are selected. Variables included in the measurement of the urbanization level are agricultural structure, population characteristics, manufacturing and service industries, and cultural aspects such as newspaper circulation, the ratio of car ownership and piped water supply. Variables included in the measurement of functional linkage are commuting, shopping pattern, centralized service such as medical facilities and trade of agricultural products. The standardization method and factor analysis are employed in making the delineation of Seoul metropolitan region. According to the result of this study, 2 cities, 8 Eups and 46 Myuns are included Seoul metropolitan region in 1990. If we compare this delineated area in 1990 to that of 1985, we can find the distinctive pattern of expanded axes according to the main transportation routes such as Seoul-Suweon, Seoul-Gwangju, Seoul-Incheon. In 199O, all the Gyunggi province, except a few Myuns located at the north and northwest part of Gyunggi province, are included in Seoul metropolitan region. Furthermore, this study attempts to the analysis of regional structure of Seoul metropolitan region according to the functional characteristics of each city and Gun. Variables included in this analysis are the new residential function, manufacturing function, service function, education and infermation function, public facility function and agricultural function. Factor analysis and cluster analysis are employed in making regionalization. Seoul metropolitan reaion is subdivided into four subregions which reflect different functional specialization. The first group is the specialized region of newly formed residential function. The second group is the specialized reaion of manufacturing function. The third group is the specialized region of service function. And the fourth group has little specialized in terms of manufacturing, service, and residential function. But this region has some potentiality of development when Seoul metropolitan region grow continuously. Seoul metropolitan region accounted for 43% of national population, despite 11.8% of national land size in 1990. Although Seoul metropolitan region enjoys important agglomeration economies, it also has huge social cost in the form of transportation congestion, housing shortage, rapid increase of land value, environment pollution, and etc. Efficient metropolitan plan making is a vital element in promoting Seoul's economic development and providing high quality living environment at low cost. In the light of the result of this study, the outer ring of Seoul metropolitan region, especially northeastern part, are underdeveloped compared to overdeveloped southwestern area. It is needed to develop the guidelines for the implement of the growth control and management plan, inducing more balanced development for whole Seoul metropolitan reaion.

• Journal of the Korean Wood Science and Technology
• /
• v.10 no.1
• /
• pp.38-46
• /
• 1982

The research was carried out to determine the division of juvenile and adult wood from the pattern of variables of wood quality indicators, to investigate general low of the size of juwenile wood and to study the characteristics of juvenile and adult wood. For this study some trees of Pinus koraiensis were selected and several wood quality indicators such as annual ring width. late wood percentage, tracheid length tracheid diameter, wall thicknes, and microfibril angles were measured. The results of this study were summaried as follows. 1) Juvenile and adult wood can be divided into radial variations of wood quality indicators. In this study juvenile wood might be classified as a large fluctuated region of radial wood quality variations in the nearest part to pith. 2) Juvenile wood was indicated as a part of nearly cylinderical shape, averaging 6-11cm in radius, near pith. 3) Number of rings from pith of juvenile wood was about 12-20 and was nearly constant in uniform growth trees among the forest stands. 4) Usually adult wood was formed within the about 5-10m above ground.