• Title/Summary/Keyword: 해도

Search Result 22,418, Processing Time 0.054 seconds

Effect of Low Temperature Treatment of Seed Bulb and Planting Date on Plant Growth and Yield in Garlic (마늘의 파종기별(播種期別) 저온처리(低溫處理)의 차이(差異)가 생육(生育) 및 수량(收量)에 미치는 영향(影響))

  • Shin, Seong Lyon;Lee, Woo Sung
    • Current Research on Agriculture and Life Sciences
    • /
    • v.6
    • /
    • pp.49-69
    • /
    • 1988
  • In order to develop a cropping system that can produce garlic in the period of short supply from March to April, effects of low temperature treatment of seed bulbs and planting dates, starting date of low temperature treatment, days of low temperature treatment on plant growth, maturity and yield were studied in Southern strain, 'Namhae' and in Northern strain, 'Euiseong' of garlic (Allium sativum). The results obtained were as follows. In Sorthern strain, sprouting was significantly enhanced by low temperature treatment only in Sep. 14, and Sep. 29 plantings. Days to sprout were least in 30 days of low temperature treatment of Sep. 14 planting and in 45 days treatment of Sep. 29 planting. When considering on the beginning date of low temperature treatment, a marked difference was observed between treatments started before July 31 and after Aug. 15. Sprouting was most enhanced in 45 days low temperature treatment of Aug. 15 and Aug. 30 plantings. In Northern strain, sprouting was en hanced by low temperature treatment in planting from Sep. 29 to Nov. 13 and low temperature treatment for 60 days was most effective. Effect of low temperature treatment on early plant growth was observed in Sep. 14 and Sep. 29 plantings, but the effect on plant growth at intermediate stage or thereafter was observed in up to Oct. 29 plantings. Optimun days for low temperature treatment on growth enhancement was 45 and 60 days in Southern strain and 60 days in Northern strain in each planting dates. In Southern strain, the longer the low temperature treatment and the later the planting date the less the number of leaves developed. In Northern strain, normal leaves were not developed in plantings from Sep. 14 to Nov. 13. In Southern strain, clove differentiation and bulbing were earlist in 45 and 60 days treatment of Sep. 14, Sep. 29, and Oct. 14 planting initiated on July 31 and Aug. 15. In Northern strain, clove differentiation and bulbing were earlist in 60 days treatment of Oct. 14 planting initiated on Aug. 15 and Aug. 30. In treatment initiated later than above, longer the low temperature treatment the earlier the clove differentiation and bulbing in both Southern and Northern strains. The earlier the initiation date and the longer of low temperature treatment, the earlier bolting in southern strain. In Northern strain, bolting was most enhanced in 45 and 60 days of low temperature treatment initiated on Aug. 15 and Aug. 30. The longer the low temperature treatment in plantings thereafter, the earlier the bolting. The earlier the planting date garlic bulbs. Harvest date was earliest in 45 and 60 days low temperature treatment started from July 31 to Aug. 30 in Southern strain, and it was in 60 and 90 days low temperature treatment initiated from July 31 to Aug. 30 in Northern strain. Bulb weight was heaviest in 45 days low temperature treatment of Oct. 14 planting and next was in 45 days treatment of Sep. 29 planting in Southern strain. In Northern strain, bulb weight was heaviest in 60 days treatment of Oct. 14 planting and next was in 45 days treatment of Oct. 14 planting. When considered in the aspect of the beginning date of low temperature treatment, bulb weight was heaviest in 45 days treatment started on Aug. 30 in Southern strain and in 60 days treatment started on Aug. 15 in Northern strain. A high negative correlation between days to harvest and plant height on January 12, and a high positive correlation between days to harvest and days clove differentiation were observed. This indicates that enhanced plant growth and clove differentiation induced by low temperature treatment advanced the harvest date. A high negative correlation between bulb weight and days to clove differentiation, days to harvest suggests that the enhanced clove differentiation result and in heavier bulb weight. From the above results, it suggested that early crop of garlic can be harvested by planting at the period of Sep. 29 to Oct. 14 after 45 days of low temperature treatment of seed bulbs of Southern strain. Then harvest date can be shortened by 30 days compared to control and garlic can be harvested in early April.

  • PDF

Studies on the Occurrence of Upland Weeds and the Competition with Soybeans (전지(田地)와 콩밭에 있어서 잡초(雜草)의 발생(發生) 및 경합(競合)에 관한 조사(調査) 연구(硏究))

  • Lee, Key-Hong;Lee, Eun-Woong
    • Korean Journal of Weed Science
    • /
    • v.2 no.2
    • /
    • pp.75-113
    • /
    • 1982
  • Studies were carried out 1) to define the shape and size of sampling quadrat and its number of observations for weed experiments, 2) to characterize the growth and community of major summer weeds under upland condition and 3) to investigate the factors influencing competition between weeds and soybeans under weed-free and weedy conditions in early and late season cultures. No significant difference was noted among different shapes of quadrat (regular, rectangular, band, and circular) in the sampling efficiency of weeds. The results also suggested that the minimum size of quadrat was 0.25$m^2$ and the minimum number of replication was 2 times per plot. The major dominant weeds were about 10 species in the experimental field and the total number of weeds was in the range of 70 - 1,600 plants per $m^2$. Among the weeds Digitaria sanguinalis and Portulaca oleracea were the most dominant species. Growth amount and reproduction capability were also measured by weed species. Five different weed communities were identified in the field. The degree of dispersion by weed species and association among weeds were investigated. Intra-(within soybeans) and inter-specific (between soybeans and weeds) competition were studied in early and late season cultures of soybeans. The average yield of soybeans per plant was significantly decreased in both season cultures due to intra-specific competition as the planting density of soybeans increased, On the other hand, the average yield of soybeans per l0a was proportionally increased to the increase of planting density and the rate of its increase was more significant under weedy than weed-free condition. Most of the agronomic characteristics of soybeans were affected by weeds and its degree was greater in sparse planting than in dense planting and in early season than in late-season culture. Digitaria sanguinalis was the most competitive to soybeans in early season and both of Digitaria sanguinalis and Portulaca oleracea affected primarily the growth of soybeans in late season with about the same competitiveness. The occurrence of weeds was significantly decreased in early season and slightly decreased in late-season by dense planting of soybeans. The total growth amount of weeds was also considerably decreased by increase of soybean planting density both in early- and late-season cultures. The occurrence of Digitaria sanguinalis which was the most dominant in both seasons, and its growth amount was significantly decreased as the planting density of soybean was increased. On the other hand, the occurrence of Portulaca oleracea which was only dominant in late-season culture did not show significant response to the planting density of soybeans.

  • PDF

A Study on Physical and Mechanical Properties of Sawdustboards combined with Polypropylene Chip and Oriented Thread (폴리프로필렌사(絲)칩과 배향사(配向絲)를 결체(結締)한 톱밥보드의 물리적(物理的) 및 기계적(機械的) 성질(性質)에 관(關)한 연구(硏究))

  • Suh, Jin-Suk;Lee, Phil-Woo
    • Journal of the Korean Wood Science and Technology
    • /
    • v.16 no.2
    • /
    • pp.1-41
    • /
    • 1988
  • For the purpose of utilizing the sawdust having poor combining properties as board raw material and resulting in dimensional instability of board, polypropylene chip (abbreviated below as PP chip) or oriented PP thread was combined with sawdust particle from white meranti(Shorea sp.). The PP chip was prepared from PP thread in length of 0.25, 0.5, 1.0 and 1.5 cm for conventional blending application. Thereafter, the PP chip cut as above was combined with the sawdust particle by 3, 6, 9, 12 and 15% on the weight basis of board. Oriented PP threads were aligned with spacing of 0.5, 1.0 and 1.5cm along transverse direction of board. The physical and mechanical properties on one, two and three layer boards manufactured with the above combining conditions were investigated. The conclusions obtained at this study were summarized as follows: 1. In thickness swelling, all one layer boards combined with PP chips showed lower values than control sawdustboard, and gradually clear decreasing tendendy with the increase of PP chip composition. Two layer board showed higher swelling value than one layer board, but the majority of boards lower values than control sawdustboard. All three layer boards showed lower swelling values than control sawdustboard. 2. In the PP chip and oriented thread combining board, the swelling values of boards combining 0.5cm spacing oriented thread with 1.0 or 1.5cm long PP chip in 12 and 15% by board weight were much lower than the lowest of one or three layer. 3. In specific gravity of 0.51, modulus of rupture of one layer board combined with 3% PP chip showed higher value than control sawdustboard. However, moduli of rupture of the boards with every PP chip composition did not exceed 80kgf/cm2, the low limit value of type 100 board, Korean Industrial Standard KS F 3104 Particleboards. Moduli of rupture of 6%, 1.5cm-long and 3% PP chip combined boards in specific gravity of 0.63 as well as PP chip combined board in specific gravity of 0.72 exceeded 80kgf/$cm^2$ on KS F 3104. Two layer boards combined with every PI' chip composition showed lower values than control sawdustboard and one layer board. Three layer boards combined with.1.5cm long PP chip in 3, 6 and 9% combination level showed higher values than control sawdustboard, and exceeded 80kgf/$cm^2$ on KS F 3104. 4. In modulus of rupture of PP thread oriented sawdustboard, 0.5cm spacing oriented board showed the highest value, and 1.0 and 1.5cm spacing oriented boards lower values than the 0.5cm. However, all PP thread oriented sawdustboards showed higher values than control saw-dustboard. 5. Moduli of rupture in the majority of PP chip and oriented thread combining boards were higher than 80kgf/$cm^2$ on KS F 3104. Moduli of rupture in the boards combining longer PP chip with narrower 0.5cm spacing oriented thread showed high values. In accordance with the spacing increase of oriented thread, moduli of rupture in the PP chip and oriented thread combining boards showed increasing tendency compared with oriented sawdustboard. 6. Moduli of elasticity in one, two and three layer boards were lower than those of control sawdustboard, however, moduli of elasticity of oriented sawdustboards with 0.5, 1.0 and 1.5cm spacing increased 20, 18 and 10% compared with control sawdustboard, respectively. 7. Moduli of elasticity in the majority of PP chip and oriented thread combining boards in 0.5, 1.0 and 1.5cm oriented spacing showed much higher values than control sawdustboard. On the whole, moduli of elasticity in the oriented boards combined with 9% or less combination level and 0.5cm or more length of PP chip showed higher values than oriented sawdustboard. The increasing effect on modulus of elasticity was shown by the PP chip composition in oriented board with narrow spacing. 8. Internal bond strengths of all one layer PP chip combined boards showed lower values than control sawdust board, however, the PP chip combined boards in specific gravity of 0.63 and 0.72 exceeded 1.5kgf/$cm^2$, the low limit value of type 100 board and 3kgf/$cm^2$, type 200 board on KS F 3104, respectively. And also most of all two, three layer-and oriented boards exceeded 3kgf/$cm^2$ on KS F. 9. In general, screw holding strength of one layer board combined with PP chip showed lower value than control sawdustboard, however, that of two or three layer board combined with PP chip did no decreased tendency, and even screw holding strength with the increase of PP chip composition. In the PP chip and oriented PP thread combining boards, most of the boards showed higher values than control sawdustboard in 9% or less PP chip composition.

  • PDF

A Study on the Forest Yield Regulation by Systems Analysis (시스템분석(分析)에 의(依)한 삼림수확조절(森林收穫調節)에 관(關)한 연구(硏究))

  • Cho, Eung-hyouk
    • Korean Journal of Agricultural Science
    • /
    • v.4 no.2
    • /
    • pp.344-390
    • /
    • 1977
  • The purpose of this paper was to schedule optimum cutting strategy which could maximize the total yield under certain restrictions on periodic timber removals and harvest areas from an industrial forest, based on a linear programming technique. Sensitivity of the regulation model to variations in restrictions has also been analyzed to get information on the changes of total yield in the planning period. The regulation procedure has been made on the experimental forest of the Agricultural College of Seoul National University. The forest is composed of 219 cutting units, and characterized by younger age group which is very common in Korea. The planning period is devided into 10 cutting periods of five years each, and cutting is permissible only on the stands of age groups 5-9. It is also assumed in the study that the subsequent forests are established immediately after cutting existing forests, non-stocked forest lands are planted in first cutting period, and established forests are fully stocked until next harvest. All feasible cutting regimes have been defined to each unit depending on their age groups. Total yield (Vi, k) of each regime expected in the planning period has been projected using stand yield tables and forest inventory data, and the regime which gives highest Vi, k has been selected as a optimum cutting regime. After calculating periodic yields and cutting areas, and total yield from the optimum regimes selected without any restrictions, the upper and lower limits of periodic yields(Vj-max, Vj-min) and those of periodic cutting areas (Aj-max, Aj-min) have been decided. The optimum regimes under such restrictions have been selected by linear programming. The results of the study may be summarized as follows:- 1. The fluctuations of periodic harvest yields and areas under cutting regimes selected without restrictions were very great, because of irregular composition of age classes and growing stocks of existing stands. About 68.8 percent of total yield is expected in period 10, while none of yield in periods 6 and 7. 2. After inspection of the above solution, restricted optimum cutting regimes were obtained under the restrictions of Amin=150 ha, Amax=400ha, $Vmin=5,000m^3$ and $Vmax=50,000m^3$, using LP regulation model. As a result, about $50,000m^3$ of stable harvest yield per period and a relatively balanced age group distribution is expected from period 5. In this case, the loss in total yield was about 29 percent of that of unrestricted regimes. 3. Thinning schedule could be easily treated by the model presented in the study, and the thinnings made it possible to select optimum regimes which might be effective for smoothing the wood flows, not to speak of increasing total yield in the planning period. 4. It was known that the stronger the restrictions becomes in the optimum solution the earlier the period comes in which balanced harvest yields and age group distribution can be formed. There was also a tendency in this particular case that the periodic yields were strongly affected by constraints, and the fluctuations of harvest areas depended upon the amount of periodic yields. 5. Because the total yield was decreased at the increasing rate with imposing stronger restrictions, the Joss would be very great where strict sustained yield and normal age group distribution are required in the earlier periods. 6. Total yield under the same restrictions in a period was increased by lowering the felling age and extending the range of cutting age groups. Therefore, it seemed to be advantageous for producing maximum timber yield to adopt wider range of cutting age groups with the lower limit at which the smallest utilization size of timber could be produced. 7. The LP regulation model presented in the study seemed to be useful in the Korean situation from the following point of view: (1) The model can provide forest managers with the solution of where, when, and how much to cut in order to best fulfill the owners objective. (2) Planning is visualized as a continuous process where new strateges are automatically evolved as changes in the forest environment are recognized. (3) The cost (measured as decrease in total yield) of imposing restrictions can be easily evaluated. (4) Thinning schedule can be treated without difficulty. (5) The model can be applied to irregular forests. (6) Traditional regulation methods can be rainforced by the model.

  • PDF

Studies on the Internal Changes and Germinability during the Period of Seed Maturation of Pinus koraiensis Sieb. et Zucc. (잣나무 종자(種字) 성숙과정(成熟過程)에 있어서의 내적변화(內的變化)와 발아력(發芽力)에 대(對)한 연구(硏究))

  • Min, Kyung-Hyun
    • Journal of Korean Society of Forest Science
    • /
    • v.21 no.1
    • /
    • pp.1-34
    • /
    • 1974
  • The author intended to investigate external and internal changes in the cone structure, changes in water content, sugar, fat and protein during the period of seed maturation which bears a proper germinability. The experimental results can be summarized as in the following. 1. Male flowers 1) Pollen-mother cells occur as a mass from late in April to early in May, and form pollen tetrads through meiosis early and middle of May. Pollen with simple nucleus reach maturity late in May. 2) Stamen number of a male flower is almost same as the scale number of cone and is 69-102 stamens. One stamen includes 5800-7300 pollen. 3) The shape is round and elliptical, both of a pollen has air-sac with $80-91{\mu}$ in length, and has cuticlar exine and cellulose intine. 4) Pollen germinate in 68 hours at $25^{\circ}C$ with distilled water of pH 6.0, 2% sugar and 0.8% agar. 2. Female flowers 1) Ovuliferous scales grow rapidly in late April, and differentiation of ovules begins early in May. Embryo-sac-mother cells produce pollen tetrads through meiosis in the middle of May, and flower in late May. 2) The pollinated female flowers show repeated divisions of embryo-sac nucleus, and a great number of free nuclei form a mass for overwintering. Morphogenesis of isolation in the mass structure takes place from the middle of March, and that forms albuminous bodies of aivealus in early May. 3. Formation of pollinators and embryos. 1) Archegonia produce archegonial initial cells in the middle and late April, and pollinators are produced in the late April and late in early May. 2) After pollination, Oespore nuclei are seen to divide in the late May forming a layer of suspensor from the diaphragm in early June and in the middle of June. Thus this happens to show 4 pro-embryos. The organ of embryos begins to differentiate 1 pro-embryo and reachs perfect maturation in late August. 4. The growth of cones 1) In the year of flowering, strobiles grow during the period from the middle of June to the middle of July, and do not grow after the middle of August. Strobiles grow 1.6 times more in length 3.3 times short in diameter and about 22 times more weight than those of female flower in the year of flowering. 2) The cones at the adult stage grow 7 times longer in diameter, 12-15 times shorter diameter than those of strobiles after flowering. 3) Cone has 96-133 scales with the ratio of scale to be 69-80% and the length of cone is 11-13cm. Diameter is 5-8cm with 160-190g weight, and the seed number of it is 90-150 having empty seed ratio of 8-15%. 5. Formation of seed-coats 1) The layers of outer seed-coat become most for the width of $703{\mu}$ in the middle of July. At the adult stage of seed, it becomes $550-580{\mu}$ in size by decreasing moisture content. Then a horny and the cortical tissue of outer coats become differentiated. 2) The outer seed-coat of mature seeds forms epidermal cells of 3-4 layers and the stone cells of 16-21 layers. The interior part of it becomes parenchyma layer of 1 or 2 rows. 3) Inner seed-coat is formed 2 months earlier than the outer seed-coat in the middle of May, having the most width of inner seed-coat $667{\mu}$. At the adult stage it loses to $80-90{\mu}$. 6. Change in moisture content After pollination moisture content becomes gradually increased at the top in the early June and becomes markedly decreased in the middle of August. At the adult stage it shows 43~48% in cone, 23~25% in the outer seed-coat, 32~37% in the inner seed-coat, 23~26% in the inner seed-coat and endosperm and embryo, 21~24% in the embryo and endosperm, 36~40% in the embryos. 7. The content compositions of seed 1) Fat contents become gradually increased after the early May, at the adult stage it occupies 65~85% more fat than walnut and palm. Embryo includes 78.8% fat, and 57.0% fat in endosperm. 2) Sugar content after pollination becomes greatly increased as in the case of reducing sugar, while non-reducing sugar becomes increased in the early June. 3) Crude protein content becomes gradually increased after the early May, and at the adult stage it becomes 48.8%. Endosperm is made up with more protein than embryo. 8. The test of germination The collected optimum period of Pinus koraiensis seeds at an adequate maturity was collected in the early September, and used for the germination test of reduction-method and embryo culture. Seeds were taken at the interval of 7 days from the middle of July to the middle of September for the germination test at germination apparatus.

  • PDF

New Trends in the Production of One Hundred Fans Paintings in the Late Joseon Period: The One Hundred Fans Painting in the Museum am Rothenbaum Kulturen und Künste der Welt in Germany and Its Original Drawings at the National Museum of Korea (조선말기 백선도(百扇圖)의 새로운 제작경향 - 독일 로텐바움세계문화예술박물관 소장 <백선도(百扇圖)>와 국립중앙박물관 소장 <백선도(百扇圖) 초본(草本)>을 중심으로 -)

  • Kwon, Hyeeun
    • MISULJARYO - National Museum of Korea Art Journal
    • /
    • v.96
    • /
    • pp.239-260
    • /
    • 2019
  • This paper examines the circulation and dissemination of painting during and after the nineteenth century through a case study on the One Hundred Fans paintings produced as decorative folding screens at the time. One Hundred Fans paintings refer to depictions of layers of fans in various shapes on which pictures of diverse themes are drawn. Fans and paintings on fans were depicted on paintings before the nineteenth century. However, it was in the nineteenth century that they began to be applied as subject matter for decorative paintings. Reflecting the trend of enjoying extravagant hobbies, fans and paintings on fans were mainly produced as folding screens. The folding screen of One Hundred Fans from the collection of the Museum am Rothenbaum Kulturen und Künste der Welt (hereafter Rothenbaum Museum) in Germany was first introduced to Korean in the exhibition The City in Art, Art in the City held at the National Museum of Korea in 2016. Each panel in this six-panel folding screen features more than five different fans painted with diverse topics. This folding screen is of particular significance since the National Museum of Korea holds the original drawings. In the nineteenth century, calligraphy and painting that had formerly been enjoyed by Joseon royal family members and the nobility in private spaces began to spread among common people and was distributed through markets. In accordance with the trend of adorning households, colorful decorative paintings were preferred, leading to the popularization of the production of One Hundred Fans folding screens with pictures in different shapes and themes. A majority of the Korean collection in the Rothenbaum Museum belonged to Heinrich Constantin Eduard Meyer(1841~1926), a German businessman who served as the Joseon consul general in Germany. From the late 1890s until 1905, Meyer traveled back and forth between Joseon and Germany and collected a wide range of Korean artifacts. After returning to Germany, he sequentially donated his collections, including One Hundred Fans, to the Rothenbaum Museum. Folding screens like One Hundred Fans with their fresh and decorative beauty may have attracted the attention of foreigners living in Joseon. The One Hundred Fans at the Rothenbaum Museum is an intriguing work in that during its treatment, a piece of paper with the inscription of the place name "Donghyeon" was found pasted upside down on the back of the second panel. Donghyeon was situated in between Euljiro 1-ga and Euljiro 2-ga in present-day Seoul. During the Joseon Dynasty, a domestic handicraft industry boomed in the area based on licensed shops and government offices, including the Dohwaseo (Royal Bureau of Painting), Hyeminseo (Royal Bureau of Public Dispensary), and Jangagwon (Royal Bureau of Music). In fact, in the early 1900s, shops selling calligraphy and painting existed in Donghyeon. Thus, it is very likely that the shops where Meyer purchased his collection of calligraphy and painting were located in Donghyeon. The six-panel folding screen One Hundred Fans in the collection of the Rothenbaum Museum is thought to have acquired its present form during a process of restoring Korean artifacts works in the 1980s. The original drawings of One Hundred Fans currently housed in the National Museum of Korea was acquired by the National Folk Museum of Korea between 1945 and 1950. Among the seven drawings of the painting, six indicate the order of their panels in the margins, which relates that the painting was originally an eight-panel folding screen. Each drawing shows more than five different fans. The details of these fans, including small decorations and patterns on the ribs, are realistically depicted. The names of the colors to be applied, including 'red ocher', 'red', 'ink', and 'blue', are written on most of the fans, while some are left empty or 'oil' is indicated on them. Ten fans have sketches of flowers, plants, and insects or historical figures. A comparison between these drawings and the folding screen of One Hundred Fans at the Rothenbaum Museum has revealed that their size and proportion are identical. This shows that the Rothenbaum Museum painting follows the directions set forth in the original drawings. The fans on the folding screen of One Hundred Fans at the Rothenbaum Museum are painted with images on diverse themes, including landscapes, narrative figures, birds and flowers, birds and animals, plants and insects, and fish and crabs. In particular, flowers and butterflies and fish and crabs were popular themes favored by nineteenth century Joseon painters. It is noteworthy that the folding screen One Hundred Fans at the Rothenbaum Museum includes several scenes recalling the typical painting style of Kim Hong-do, unlike other folding screens of One Hundred Fans or Various Paintings and Calligraphy. As a case in point, the theme of "Elegant Gathering in the Western Garden" is depicted in the Rothenbaum folding screen even though it is not commonly included in folding screens of One Hundred Fans or One Hundred Paintings due to spatial limitations. The scene of "Elegant Gathering in the Western Garden" in the Rothenbaum folding screen bears a resemblance to Kim Hong-do's folding screen of Elegant Gathering in the Western Garden at the National Museum of Korea in terms of its composition and style. Moreover, a few scenes on the Rothenbaum folding screen are similar to examples in the Painting Album of Byeongjin Year produced by Kim Hong-do in 1796. The painter who drew the fan paintings on the Rothenbaum folding screen is presumed to have been influenced by Kim Hong-do since the fan paintings of a landscape similar to Sainsam Rock, an Elegant Gathering in the Western Garden, and a Pair of Pheasants are all reminiscent of Kim's style. These paintings in the style of Kim Hong-do are reproduced on the fans left empty in the original drawings. The figure who produced both the original drawings and fan paintings appears to have been a professional painter influenced by Kim Hong-do. He might have appreciated Kim's Painting Album of Byeongjin Year or created duplicates of Painting Album of Byeongjin Year for circulation in the art market. We have so far identified about ten folding screens remaining with the One Hundred Fans. The composition of these folding screens are similar each other except for a slight difference in the number and proportion of the fans or reversed left and right sides of the fans. Such uniform composition can be also found in the paintings of scholar's accoutrements in the nineteenth century. This suggests that the increasing demand for calligraphy and painting in the nineteenth century led to the application of manuals for the mass production of decorative paintings. As the demand for colorful decorative folding screens with intricate designs increased from the nineteenth century, original drawings began to be used as models for producing various paintings. These were fully utilized when making large-scale folding screens with images such as Guo Ziyi's Enjoyment-of-Life Banquet, Banquet of the Queen Mother of the West, One Hundred Children, and the Sun, Cranes and Heavenly Peaches, all of which entailed complicated patterns. In fact, several designs repeatedly emerge in the extant folding screens, suggesting the use of original drawings as models. A tendency toward using original drawings as models for producing folding screens in large quantities in accordance with market demand is reflected in the production of the folding screens of One Hundred Fans filled with fans in different shapes and fan paintings on diverse themes. In the case of the folding screens of One Hundred Paintings, bordering frames are drawn first and then various paintings are executed inside the frames. In folding screens of One Hundred Fans, however, fans in diverse forms were drawn first. Accordingly, it must have been difficult to produce them in bulk. Existing examples are relatively fewer than other folding screens. As discussed above, the folding screen of One Hundred Fans at the Rothenbaum Museum and its original drawings at the National Museum of Korea aptly demonstrate the late Joseon painting trend of embracing and employing new painting styles. Further in-depth research into the Rothenbaum painting is required in that it is a rare example exhibiting the influence of Kim Hong-do compared to other paintings on the theme of One Hundred Fans whose composition and painting style are more similar to those found in the work of Bak Gi-jun.

A Study on Forest Insurance (산림보험(山林保險)에 관한 연구(硏究))

  • Park, Tai Sik
    • Journal of Korean Society of Forest Science
    • /
    • v.15 no.1
    • /
    • pp.1-38
    • /
    • 1972
  • 1. Objective of the Study The objective of the study was to make fundamental suggestions for drawing a forest insurance system applicable in Korea by investigating forest insurance systems undertaken in foreign countries, analyzing the forest hazards occurred in entire forests of Korea in the past, and hearing the opinions of people engaged in forestry. 2. Methods of the Study First, reference studies on insurance at large as well as on forest insurance were intensively made to draw the characteristics of forest insurance practiced in main forestry countries, Second, the investigations of forest hazards in Korea for the past ten years were made with the help of the Office of Forestry. Third, the questionnaires concerning forest insurance were prepared and delivered at random to 533 personnel who are working at different administrative offices of forestry, forest stations, forest cooperatives, colleges and universities, research institutes, and fire insurance companies. Fourth, fifty three representative forest owners in the area of three forest types (coniferous, hardwood, and mixed forest), a representative region in Kyonggi Province out of fourteen collective forest development programs in Korea, were directly interviewed with the writer. 3. Results of the Study The rate of response to the questionnaire was 74.40% as shown in the table 3, and the results of the questionaire were as follows: (% in the parenthes shows the rates of response; shortages in amount to 100% were due to the facts of excluding the rates of response of minor respondents). 1) Necessity of forest insurance The respondents expressed their opinions that forest insurance must be undertaken to assure forest financing (5.65%); for receiving the reimbursement of replanting costs in case of damages done (35.87%); and to protect silvicultural investments (46.74%). 2) Law of forest insurance Few respondents showed their views in favor of applying the general insurance regulations to forest insurance practice (9.35%), but the majority of respondents were in favor of passing a special forest insurance law in the light of forest characteristics (88.26%). 3) Sorts of institutes to undertake forest insurance A few respondents believed that insurance companies at large could take care of forest insurance (17.42%); forest owner's mutual associations would manage the forest insurance more effectively (23.53%); but the more than half of the respondents were in favor of establishing public or national forest insurance institutes (56.18%). 4) Kinds of risks to be undertaken in forest insurance It would be desirable that the risks to be undertaken in forest insurance be limited: To forest fire hazards only (23.38%); to forest fire hazards plus damages made by weather (14.32%); to forest fire hazards, weather damages, and insect damages (60.68%). 5) Objectives to be insured It was responded that the objectives to be included in forest insurance should be limited: (1) To artificial coniferous forest only (13.47%); (2) to both coniferous and broad-leaved artificial forests (23.74%); (3) but the more than half of the respondents showed their desire that all the forests regardless of species and the methods of establishment should be insured (61.64%). 6) Range of risks in age of trees to be included in forest insurance The opinions of the respondents showed that it might be enough to insure the trees less than ten years of age (15.23%); but it would be more desirous of taking up forest trees under twenty years of age (32.95%); nevertheless, a large number of respondents were in favor of underwriting all the forest trees less than fourty years of age (46.37%). 7) Term of a forest insurance contract Quite a few respondents favored a contract made on one year basis (31.74%), but the more than half of the respondents favored the contract made on five year bases (58.68%). 8) Limitation in a forest insurance contract The respondents indicated that it would be desirable in a forest insurance contract to exclude forests less than five hectars (20.78%), but more than half of the respondents expressed their opinions that forests above a minimum volume or number of trees per unit area should be included in a forest insurance contract regardless of the area of forest lands (63.77%). 9) Methods of contract Some responded that it would be good to let the forest owners choose their forests in making a forest insurance contract (32.13%); others inclined to think that it would be desirable to include all the forests that owners hold whenerver they decide to make a forest insurance contract (33.48%); the rest responded in favor of forcing the owners to buy insurance policy if they own the forests that were established with subsidy or own highly vauable growing stock (31.92%) 10) Rate of premium The responses were divided into three categories: (1) The rate of primium is to be decided according to the regional degree of risks(27.72%); (2) to be decided by taking consideration both regional degree of risks and insurable values(31.59%); (3) and to be decided according to the rate of risks for the entire country and the insurable values (39.55%). 11) Payment of Premium Although a few respondents wished to make a payment of premium at once for a short term forest insurance contract, and an annual payment for a long term contract (13.80%); the majority of the respondents wished to pay the premium annually regardless of the term of contract, by employing a high rate of premium on a short term contract, but a low rate on a long term contract (83.71%). 12) Institutes in charge of forest insurance business A few respondents showed their desire that forest insurance be taken care of at the government forest administrative offices (18.75%); others at insurance companies (35.76%); but the rest, the largest number of the respondents, favored forest associations in the county. They also wanted to pay a certain rate of premium to the forest associations that issue the insurance (44.22%). 13) Limitation on indemnity for damages done In limitation on indemnity for damages done, the respondents showed a quite different views. Some desired compesation to cover replanting costs when young stands suffered damages and to be paid at the rate of eighty percent to the losses received when matured timber stands suffered damages(29.70%); others desired to receive compensation of the actual total loss valued at present market prices (31.07%); but the rest responded in favor of compensation at the present value figured out by applying a certain rate of prolongation factors to the establishment costs(36.99%). 14) Raising of funds for forest insurance A few respondents hoped to raise the fund for forest insurance by setting aside certain amount of money from the indemnity paid (15.65%); others wished to raise the fund by levying new forest land taxes(33.79%); but the rest expressed their hope to raise the fund by reserving certain amount of money from the surplus money that was saved due to the non-risks (44.81%). 15) Causes of fires The main causes of forest fires 6gured out by the respondents experience turned out to be (1) an accidental fire, (2) cigarettes, (3) shifting cultivation. The reponses were coincided with the forest fire analysis made by the Office of Forestry. 16) Fire prevention The respondents suggested that the most important and practical three kinds of forest fire prevention measures would be (1) providing a fire-break, (2) keeping passers-by out during the drought seasons, (3) enlightenment through mass communication systems. 4. Suggestions The writer wishes to present some suggestions that seemed helpful in drawing up a forest insurance system by reviewing the findings in the questionaire analysis and the results of investigations on forest insurance undertaken in foreign countries. 1) A forest insurance system designed to compensate the loss figured out on the basis of replanting cost when young forest stands suffered damages, and to strengthen credit rating by relieving of risks of damages, must be put in practice as soon as possible with the enactment of a specifically drawn forest insurance law. And the committee of forest insurance should be organized to make a full study of forest insurance system. 2) Two kinds of forest insurance organizations furnishing forest insurance, publicly-owned insurance organizations and privately-owned, are desirable in order to handle forest risks properly. The privately-owned forest insurance organizations should take up forest fire insurance only, and the publicly-owned ought to write insurance for forest fires and insect damages. 3) The privately-owned organizations furnishing forest insurance are desired to take up all the forest stands older than twenty years; whereas, the publicly-owned should sell forest insurance on artificially planted stands younger than twenty years with emphasis on compensating replanting costs of forest stands when they suffer damages. 4) Small forest stands, less than one hectare holding volume or stocked at smaller than standard per unit area are not to be included in a forest insurance writing, and the minimum term of insuring should not be longer than one year in the privately-owned forest insurance organizations although insuring period could be extended more than one year; whereas, consecutive five year term of insurance periods should be set as a mimimum period of insuring forest in the publicly-owned forest insurance organizations. 5) The forest owners should be free in selecting their forests in insuring; whereas, forest owners of the stands that were established with subsidy should be required to insure their forests at publicly-owned forest insurance organizations. 6) Annual insurance premiums for both publicly-owned and privately-owned forest insurance organizations ought to be figured out in proportion to the amount of insurance in accordance with the degree of risks which are grouped into three categories on the basis of the rate of risks throughout the country. 7) Annual premium should be paid at the beginning of forest insurance contract, but reduction must be made if the insuring periods extend longer than a minimum period of forest insurance set by the law. 8) The compensation for damages, the reimbursement, should be figured out on the basis of the ratio between the amount of insurance and insurable value. In the publicly-owned forest insurance system, the standard amount of insurance should be set on the basis of establishment costs in order to prevent over-compensation. 9) Forest insurance business is to be taken care of at the window of insurance com pnies when forest owners buy the privately-owned forest insurance, but the business of writing the publicly-owned forest insurance should be done through the forest cooperatives and certain portions of the premium be reimbursed to the forest cooperatives. 10) Forest insurance funds ought to be reserved by levying a property tax on forest lands. 11) In order to prevent forest damages, the forest owners should be required to report forest hazards immediately to the forest insurance organizations and the latter should bear the responsibility of taking preventive measures.

  • PDF

Effects of Boliing, Steaming, and Chemical Treatment on Solid Wood Bending of Quercus acutissima Carr. and Pinus densiflora S. et. Z. (자비(煮沸), 증자(蒸煮) 및 약제처리(藥劑處理)가 상수리나무와 소나무의 휨가공성(加工性)에 미치는 영향(影響))

  • So, Won-Tek
    • Journal of the Korean Wood Science and Technology
    • /
    • v.13 no.1
    • /
    • pp.19-62
    • /
    • 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.

  • PDF