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Measurement of Distributed Temperature and Strain Using Raman OTDR with a Fiber Line Including Fiber Bragg Grating Sensors (광섬유 브래그 격자 센서가 있는 광섬유 라인에 라만 OTDR을 이용한 분포 온도 및 변형률 측정 가능성에 대한 연구)

  • Kwon, Il-Bum;Byeon, Jong-Hyun;Jeon, Min-Yong
    • Journal of the Korean Society for Nondestructive Testing
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    • v.36 no.6
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    • pp.443-450
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    • 2016
  • In this study, we propose a novel fiber optic sensor to show the measurement feasibility of distributed temperature and strains in a single sensing fiber line. Distributed temperature can be measured using optical time domain reflectometry (OTDR) with a Raman anti-Stokes light in the sensing fiber line. Moreover, the strain can be measured by fiber Bragg gratings (FBGs) in the same sensing fiber line. The anti-Stokes Raman back-scattering lights from both ends of the sensing fiber, which consists of a 4 km single mode optical fiber, are acquired and inserted into a newly formulated equation to calculate the temperature. Furthermore, the center wavelengths from the FBGs in the sensing fiber are detected by an optical spectrum analyzer; these are converted to strain values. The initial wavelengths of the FBGs are selected to avoid a cross-talk with the wavelength of the Raman pulsed pump light. Wavelength shifts from a tension test were found to be 0.1 nm, 0.17 nm, 0.29 nm, and 0.00 nm, with corresponding strain values of $85.76{\mu}{\epsilon}$, $145.55{\mu}{\epsilon}$, $247.86{\mu}{\epsilon}$, and $0.00{\mu}{\epsilon}$, respectively. In addition, a 50 m portion of the sensing fiber from $30^{\circ}C$ to $70^{\circ}C$ at $10^{\circ}C$ intervals was used to measure the distributed temperature. In all tests, the temperature measurement accuracy of the proposed sensor was less than $0.50^{\circ}C$.

The Limitations of Holocaust Narratives and the Possibility of Healing Narratives Suggested by Smith's Fires in the Mirror ('홀로코스트' 서사의 한계와 스미스의 『거울 속에 반영된 분노』에 제시된 치유 서사의 가능성)

  • Jung, Sun-kug
    • Cross-Cultural Studies
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    • v.43
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    • pp.377-404
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    • 2016
  • In this paper, I intend to focus on the 1991 racial tension and violence portrayed in Anna Devear Smith's book Fires in the Mirror, which was published in book form in 1993. I make use of a series of interviews with many of those involved in the conflicts, which were based on the Jewish Holocaust and the history of African American enslavement. In Crown Heights, the black community and the Jewish community have each suffered terrible losses, but individuals and communities become rhetorically attached to foundational historical traumas that lie at the center of each group's cultural identity rather than try to understand each other's pain. Smith lets this rhetoric dominate Fires in the Mirror by putting contradictory monologues side by side in order to show how discourses on 'slavery' and 'the Holocaust' still have control over specific ethnic communities. My intention is not to delve into the conflict between the Jewish and black communities exclusively. Rather, I attempt to form an understanding of the problems of the critical/theoretical tenets proposed by 'the rhetoric of holocaust,' including the Jewish Holocaust and the black experience of enslavement. Such an understanding will help us see the failure in the theories, illuminating the ways that such rhetoric should have recognized its own violence and helped to forge a new relationship between racism and anti-Semitism. Fires in the Mirror mirrors back to us the ways that 'the Holocaust' betrays the possibility of error to indicate its own susceptibility to blindness. The cracks brought forth by conflicting narratives enable readers to observe wounds being healed and the possibility of new narrative looming up.

The opening efficiency of the miniaturized small-scale net for anchovy boat seine to reduce the fleet size (선단축소를 위한 기선권현망 축소형 소형어구의 전개성능)

  • AN, Young-Su;BACK, Young-su;JIN, Song-han;JANG, Choong-Sik;KANG, Myoung-hee;CHA, Bong-jin;CHO, Youn-hyoung;CHA, Ju-hyeng;KIM, Bo-Yeon
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.55 no.1
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    • pp.7-19
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    • 2019
  • This study was conducted in order to improve opening efficiency of the miniaturized small-scale net for anchovy boat seine gear to reduce the fleet size. Field experiment was performed to observe geometry of nets by catcher boats. When the distance between the two ships was 150, 300 and 450 m and the speed of towing nets was 0.6, 0.9, and 1.2 kt, the vertical opening and actual opening of each part of the miniaturized small-scale net was as follows: the front part of the wing net, 6.8-9.5 m, 45-63%; the middle part of the wing net, 16.1-30.7 m, 34-65%; the entrance of the inside wing net, 21.6-41.2 m, 44-84%; the square and bosom, 17.4-34.0 m, 38-75%; the entrance of the body net, 16.5-29.4 m, 36-64%; the entrance of the bag net, 14.5-21.9 m, 70-106%; the flapper, 6.7-7.7 m, 81-83%, and the end of the bag net, 8.6-10.9 m, 64-81%. The tension of towing nets was measured to be 2,734-6,812 kg approximately, which indicates that the fleet can tow nets with 350 hp, the standard engine horse power. The fishing operation time was shortened comparing to existent net with the large-scale buoy attachment operation. It was also possible to operate the ship without fish detecting boat.

Part-time Work in Sweden: The Coexistence in Tension of Flexibility and Gender Equality (스웨덴의 시간제근로: 유연성과 성평등의 긴장 속 공존)

  • Kim, Young-Mi
    • Korean Journal of Labor Studies
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    • v.17 no.1
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    • pp.297-323
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    • 2011
  • Part-time jobs in Sweden are highly feminized yet are in fair conditions in terms of job security, earnings, and collective representation. Three points are considered to be important to understand why part-time work in Sweden carries such positive characteristics. First, the part-time work in Sweden is widely spread not as a result of employers' need for labor flexibilization but as means to enhance the work-life balance, a value pursued within a broader social policy package to change the breadwinner model. Second, discrimination against part-time workers is restrained in Sweden because the boundary between part-time and full-time is not conspicuous. Most of part-time jobs are occupied by regular workers who exert the right to part-time work, hence may go back to the full-time status any time. Third, the regulation on overtime work of part-time workers as well as full-time workers is strong. It is largely agreed among researchers that part-time work contributed greatly to an increase of female employment rate in Sweden. Since the 1970s, the increased availability of part-time jobs induced married women who used to be economically inactive to the labor market and maintained them to be economically active throughout the child rearing period. From the gender perspective, one may still raise issues regarding part-time work in Sweden such as persistent feminization and strong occupational sex segregation. However, the observed trend shows that the part-time work in Sweden has functioned more as a stepping stone to the full-time work for women than as a women's trap.

Characteristics of Collapsed Retaining Walls Using Elasto-plastic Method and Finite Element Method (탄소성 방법과 유한요소법에 의한 붕괴 토류벽의 거동차이 분석)

  • Jeong, Sang-Seom;Kim, Young-Ho
    • Journal of the Korean Geotechnical Society
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    • v.25 no.4
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    • pp.19-29
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    • 2009
  • In this study, a numerical analysis was performed to predict the sequential behavior of anchored retaining wall where the failure accident took place, and verified accuracy of prediction through the comparisons between prediction and field measurement. The emphasis was given to the wall behaviors and the variation of sliding surface based on the two different methods of elasto-plastic and finite element (shear strength reduction technique). Through the comparison study, it is shown that the bending moment and the soil pressure at construction stages produce quite similar results in both the elasto-plastic and finite element method. However, predicted wall deflections using elasto-plastic method show underestimate results compared with measured deflections. This demonstrates that the elasto-plastic method does not clearly consider the influence of soil-wall-reinforcement interaction, so that the tension force (anchor force and earth pressure) on the wall is overestimated. Based on the results obtained, it is found that finite element method using shear strength reduction method can be effectively used to perform the back calculation analysis in the anchored retaining wall, whereas elasto-plastic method can be applicable to the preliminary design of retaining wall with suitable safety factor.

Prophylactic and therapeutic studies on intestinal giant-cystic disease of the Israel carp caused by yhelohunellus kitauei I. Course of formation and vanishment of the cyst (향어의 장포자충(Thelohanellus kitauei)증의 예방 및 치료에 관한 기초적 연구 I . 종유의 소장 과정)

  • 이재구;김종오
    • Parasites, Hosts and Diseases
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    • v.28 no.3
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    • pp.183-194
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    • 1990
  • In an attempt to develop prophylactic and therapeutic measures of the intestinal giant-cystic disease caused by Thelohanellus kitauei in the Israel carp, Cyprinus carpio nodus, pathological observations were conducted upon the carps which were hatched in May 1988 and raised in a net cage fish farm at the Soyang lake, managed by Horim Fisheries for the period of 21 months with 1~2 months interval. After a gross inspection of the carps, necropsy was carried out periodically in order to clarify the pathological changes in various internal organs and muscular tissues. Also. the prevalence of the disease was checked during the period from 1988 to 1990. Gross inspections revealed that the infected carps showed some degree of fading in body and gill color, back-emaciation symptoms, reddish anus accompanying erosion and relaxation and pot-belly, as well as discharge of yellowish white mucoid material from the anus. However, most carps died eventually of intestinal obstruction. Other significant necropsy fadings included cyst formation of various size in the intestinal mucosa, ascites, anemic condition through internal organs and muscular tissues, hyperemia and dilation of intestines with decreased tension, thinness and fragility, and full contents of semi-fluid or yellowish white mucoid material in the intestinal canals. Based on the morphological characteristics of the spores found in the cysts, parasitic location in the intestines, macro- and microscopic findings of the lesions, the parasites were identised as Thelohanellus kitauei Egusa os Nakajima, 1981. Although monthly changes of water temperature were distinct, the extrusion rates of the polar filaments of the spores stayed constant throughout the year with an exception of a lower rate in July, The lesions initiated from mucosa and submucosa in early July became large swellings and then complete mature (orms following the peracute course. From late August the upper cysts were gradually opened and most of the spores were dispersed from anus into the surrounding water through December but only a few lasted until next April. The cysts were completely recovered until next September. Comparing the incidence and prevalence of the disease by year tremendous infection and death rates were checked in the first prevalent year, 1988, but the rates were significantly decreased in the second year, and showed an almost normal status in the third year, 1990. As the above summarized results showed, the disease entity might come to an end in three years after the first prevalent year, however, the spores must be strictly prevented because they could be infective in the water for one year.

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The Origination and Changes of Street Fashion (스트리트 패션의 발생과 변천)

  • Jung, Kyong-Hee;Yoo, Tai-Soon
    • Journal of Fashion Business
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    • v.1 no.1
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    • pp.71-83
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    • 1997
  • The purpose of this study is to analyze the present fashion phenomenon by considering the types of street fashion, the center of avant-grade modern fashion, that shows the origination background and special feature concretely. The times was defined through the 1980's from World War II that street style originated, so the range of study was the 1990's when the street style was influenced by that of the past and was revived. The ways of study were to analyze the records of ideology, art and music connected with the street style from World War II to the present when it has risen. The summary of result is as follows. (1) In the 1940's, Zooties was the jet of desire suppressed by African-Americans that couldn't receive favors socially and economically and Hipsters pursued reformative bebop that made up of soft Jazz. In the 1950's, Modernists were running after Cool Jazz to the minimum. In the 1970's, Funk appered in the sexual desire and erotic strength, and was surfaced from Negro Getto. In the 1980's B-boys & Flygirls showed the street style by the scribble art of slum in the New York. As mentioned above, In the 1990's, Acid Jazz influenced by the Jazz of Negro has been the fashion added to the tradition of musical form that come from eclecticism of Jazz tended Neo-Jazz. (2) In the 1940's, Western style dreamed the country life because of rapid urbanization. In the 1950's, Beat obtained the feeling of liberation from the dissolute life and activity. In the 1960's, Psychedelics showed the freedom affected by the Pop-art and Op-art, and Hippies pursued the true individuality as 'love & peace' life style and the return to nature. In the 1990's, Grunge look influenced by the above has been fashion that shows the practical use of second-hand clothing or patchwork contrary to elitism. (3) In the 1940's, Caribbean style appered in the typical textile color with the center of West Indies. In the 1960's, Rude boys showed the magnificence and difficulty of Jamaica, and Rastafarians had a tendency to come back to the ancient civilization of America. In the 1970's, Two-tone was the simple clothing for harmonizing among human races. In the 1990's, Jamaica look influenced by the above has been the Lege fashion introduced to a high fashion, appearing in the special bright color, applique, unique hair style, and so on. (4) In the 1950's, Sufers pursued natural rhythm, getting out of everything. In the 1970' s, Skaters enjoyed the speed on the paved road. In the 1980's, Casuals emphasized the spirit of cooperation of young-things. In the 1990's, Casual look Influenced by the above has been the fashion that forms the activity, function and strong spirit of cooperation by pursuing comfortable life and sports in the tension of life and variety of modern society. (5) It was hard for Bikers to adjust themselves in society after the war. In the 1950's, Coffee bar cowboys were the reckless running boys in the leather jacket. In the 1960's, Rockers created the group originality as disobedient outsiders and Greasers imitated Rolling Stones. In the 1980's, Punks resisted the viewpoint of the old generation in offensive fashion. In the 1990's, Cyberpunk influenced by the above has pursued the classless structure, electronic music and metallic clothing that forebodes gloomily as the computer generation of ultra-modern science times. Accordingly, in understanding a complex modern fashion phenomenon, it was analyzed that the street styles of the past, from World War II to the 1980's, were reflected in that of the 1990's dividing into the five types in a word, namely Acid Jazz, Grunge look, Jamaica look, Casual look and Cyberpunk.

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Cartoon Criticism; The subject and the gaze based on Lacan' s theory otherness of vision : focusing on KUBRICK of Kang, Do-Ha (라캉의 시각의 타자성(대상 a)에 근거한 만화비평으로서의 주체와 응시 : 강도하의 큐브릭을 중심으로)

  • Yang, Seung-Kyu
    • Cartoon and Animation Studies
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    • s.26
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    • pp.79-108
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    • 2012
  • This thesis is on the purpose of seeking for the possibility of a mechanism in interpreting, analyzing and criticizing cartoons which are applied to the concept of "the gaze" based on "the otherness of vision", which states a pluralistic visual world. It proves that cartoons are in line with other art works that are the subject to "lack and desire"; the gaze, greets reality and acts as an important criterion of analyzing and criticizing the trend in contemporary art, in which the cartoon expresses the gaze in harmony within its work of art. In this thesis, the artist, Kang Doh-ha structuralized ambiguous and difficult forms of art as he has cumulated experimental minds by working in an indie cartoon plane for a long period of time. Among his works of art, he identified the "invisible world" through his piece "Kubrik". Therefore, he represented: a metaphor and a metonymy, an ambiguously situational expression, an intentional and emotional error, the structure of individuality and integration, and finally tension beyond its meaning through use of 'the gaze' that is both the cause and the subject of a desire in the visible world which Lacan academized when he interpreted and analyzed "Kubrik". The concept of the gaze can be used in a variety of ways to display one another's presence in relation each character, revealing a spot of lack by staring back at readers or audiences and furthermore, to analyze and criticize the hidden side of the art piece by critics. The most important details are the artist's gaze, which is seen in the eyes of the analysis and also his or her criticism of the cartoon, which functions as a metaphoric screen in which the subject himself or herself betrays the law of desires thus enabling the violent and cruel reality to be masked and indulged in plays. This will serve as an element that will lead into an art as well as control the degradation to just a piece of enjoyment with the cartoon remaining only within the visual world.

The Effect of Users' Personality on Emotional and Cognitive Evaluation in UCC Web Site Usage (UCC(user-created-contents) 웹 사이트에서 사용자의 인성이 감정적, 인지적 평가와 UCC 활용에 미치는 영향)

  • Moon, Yun-Ji;Kang, So-Ra;Kim, Woo-Gon
    • Asia pacific journal of information systems
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    • v.20 no.3
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    • pp.167-190
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    • 2010
  • The research conducted here focuses on the effect of factors that affect the behavior of UCC (User Created Content) website users, other than user's rational recognition of how useful a UCC website can be. Most discussions in the existing literature on information systems have focused on users' evaluation how a UCC website can help to attain the users' own goals. However, there are other factors and this research pays attention to an individual's 'personality,' which is stable and biological in nature. Specifically, I have noted here that 'extroversion' and 'neuroticism,' the two common personality factors presented in Eysenck's most representative 'EPQ Model' and 'Big Five Model,' are the two personality factors that affect a site's 'usefulness,' by this I mean how useful does the user consider the website and its content. How useful a site is considered by the user is the other factor that has been regarded as the antecedent factor that influences the adoption of information systems in the existing MIS (Management Information System) research. Secondly, as using or creating a UCC website does not guarantee the user's or the creator's extrinsic motivation, unlike when using the information system within an organization, there is a greater likelihood that the increase in user's activities in relation to a UCC website is motivated by emotional factors rather than rational factors. Thus, I have decided to include the relationship between an individual's personality and what they find pleasurable in the research model. Thirdly, when based on the S-O-R Paradigm of Mehrabian and Russell, the two cognitive factors and emotional factors are finally affected by stimulus, and thus these factors ultimately have an effect on an individual's respondent behavior. Therefore, this research has presented an assumption that the recognition of how useful the site and content is and what emotional pleasure it provides will finally affect the behavior of the UCC website users. Finally, the relationship between the recognition of how useful a site is and how pleasurable it is to useand UCC usage may differ depending on certain situational conditions. In other words, the relationship between the three factors may vary according to how much users are involved in the creation of the website content. Creation thus emerges as the keyword of UCC. I analyzed the above relationships through the moderating variable of the user's involvement in the creation of the site. The research result shows the following: When it comes to the relationship between an individual's personality and what they find pleasurable it is extroverted users who have a greater likelihood to feel pleasure when using a UCC website, as was expected in this research. This in turn leads to a more active usage of the UCC web site because a person who is an extrovert likes to spend time on activities with other people, is sensitive to new experiences and stimuli and thus actively responds to these. An extroverted person accepts new UCC activities as part of his/her social life, rather than getting away from this new UCC environment. This is represented by the term 'Foxonomy' where the users meet a variety of users from all over the world and contact new types of content created by these users. However, neuroticism creates the opposite situation to that created by extroversion. The representative symptoms of neuroticism are instability, stress, and tension. These dispositions are more closely related to stress caused by a new environment rather than this creatingcuriosity or pleasure. Thus, neurotic persons have an uneasy feeling and will eventually avoid the situation where their own or others' daily lives are frequently exposed to the open web environment, this eventually makes them have a negative attitude towards the web environment. When it comes to an individual's personality and how useful site is, the two personality factors of extroversion and neuroticism both have a positive relationship with the recognition of how useful the site and its content is. The positive, curious, and social dispositions of extroverted persons tend to make them consider the future usefulness and possibilities of a new type of information system, or website, based on their positive attitude, which has a significant influence on the recognition of how useful these UCC sites are. Neuroticism also favorably affects how useful a UCC website can be through a different mechanism from that of extroversion. As the neurotic persons tend to feel uneasy and have much doubt about a new type of information system, they actively explore its usefulness in order to relieve their uncomfortable feelings. In other words, neurotic persons seek out how useful a site can be in order to secure their own stable feelings. Meanwhile, extroverted persons explore how useful a site can be because of their positive attitude and curiosity. As a lot of MIS research has revealed that the recognition of how useful a site can be and how pleasurable it can be to use have been proven to have a significant effect on UCC activity. However, the relationship between these factors reveals different aspects based on the user's involvement in creation. This factor of creationgauges the interest of users in the creation of UCC contents. Involvement is a variable that shows the level of an individual's mental effort in creating UCC contents. When a user is highly involved in the creation process and makes an enormous effort to create UCC content (classed a part of a high-involvement group), their own pleasure and recognition of how useful the site is have a significantly higher effect on the future usage of the UCC contents, more significantly than the users who sit back and just retrieve the UCC content created by others. The cognitive and emotional response of those in the low-involvement group is unlikely to last long,even if they recognize the contents of a UCC website is pleasurable and useful to them. However, the high-involvement group tends to participate in the creation and the usage of UCC more favorably, connecting the experience with their own goals. In this respect, this research presents an answer to the question; why so many people are participating in the usage of UCC, the representative form of the Web 2.0 that has drastically involved more and more people in the creation of UCC, even if they cannot gain any monetary or social compensation. Neither information system nor a website can succeed unless it secures a certain level of user base. Moreover, it cannot be further developed when the reasons, or problems, for people's participation are not suitably explored, even if it has a certain user base. Thus, what is significant in this research is that it has studied users' respondent behavior based on an individual's innate personality, emotion, and cognitive interaction, unlike the existing research that has focused on 'compensation' to explain users' participation with the UCC website. There are also limitations in this research. Firstly, I divided an individual's personality into extroversion and neuroticism; however, there are many other personal factors such as neuro-psychiatricism, which also needs to be analyzed for its influence on UCC activities. Secondly, as a UCC website comes in many types such as multimedia, Wikis, and podcasting, these types need to be included as a sub-category of the UCC websites and their relationship with personality, emotion, cognition, and behavior also needs to be analyzed.

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
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    • v.13 no.1
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    • pp.19-62
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    • 1985
  • This study was performed to investigate: (i) the bending processing properties of silk worm oak (Quercus acutissima Carr.) and Korean red pine (Pinus densiflora S. et Z.) by boiling and steaming treatments; (ii) the effects of interrelated factors - sapwood and heartwood, annual ring placement, softening temperature and time, moisture content. and wood defects on bending processing properties; (iii) the changing rates of bending radii after release from a tension strap, and (iv) the improving methods of bending process by treatment with chemicals. The size of specimens tested was $15{\times}15{\times}350mm$ for boiling and steaming treatments and $5{\times}10{\times}200mm$ for treatments with chemicals. The specimens were green for boiling treatments and dried to 15 percent for steaming treatments. The specimens for treatments with chemicals were soaked in saturated urea solution, 35 percent formaldehyde solution, 25 percent polyethylene glycol -400 solution, and 25 percent ammonium hydroxide solution for 5 days and immediately followed the bending process, respectively. The results obtained were as follows: 1. The internal temperature of silk worm oak and Korean red pine by boiling and steaming time was raised slowly to $30^{\circ}C$ but rapidly from $30^{\circ}C$ to $80-90^{\circ}C$ and then slowly from $80-90^{\circ}C$ to $100^{\circ}C$. 2. The softening time required to the final temperature was directly proportional to the thickness of specimen. The time required from $25^{\circ}C$ to $100^{\circ}C$ for 15mm-squared specimen was 9.6-11.2 minutes in silk worm oak and 7.6-8.1 minutes in Korean red pine. 3. The moisture content (M.C.) of specimen by steaming time was increased rapidly first 4 minutes in the both species, and moderately from 4 to 20 minutes and then slowly and constantly in silk worm oak, and moderately from 4 to 15 minutes and then slowly and constantly in Korean red pine. The M.C. of 15mm-squared specimen in 50 minutes of steaming was increased to 18.0 percent in the oak and 22.4 percent in the pine from the initial conditioned M.C. of 15 percent The rate of moisture adsorption measured was therefore faster in the pine than in the oak. 4. The mechanical properties of the both species were decreased significantly with the increase of boiling rime. The decrement by the boiling treatment for 60 minutes was measured to 36.6-45.0 percent in compressive strength, 12.5-17.5 percent in tensile strength, 31.6-40.9 percent in modulus of rupture, and 23.3-34.6 percent in modulus of elasticity. 5. The minimum bending radius (M.B.R.) of sapwood and heartwood was 60-80 mm and 90 mm in silk worm oak, and 260 - 300 mm and 280 - 300 mm in Korean red pine, respectively. Therefore, the both species showed better bending processing properties in sapwood than in heartwood. 6. The M.B.R. of edge-grained and flat-grained specimen in suk worm oak was 60-80 mm, but the M.B.R. in Korean red pine was 240-280 mm and 260-360 mm, respectively. Comparing the M.B.R. of edge-grained with flat-grained specimen, in the pine the edge-grained showed better bending processing property than the flat-grained. 7. The bending processing properties of the both species were improved by the rising of softening temperature from $40^{\circ}C$ to $100^{\circ}C$. The minimum softening temperature for bending was $90^{\circ}C$ in silk worm oak and $80^{\circ}C$ in Korean red pine, and the dependency of softening temperature for bending was therefore higher in the oak than in the pine. 8. The bending processing properties of the both species were improved by the increase of softening time as well as temperature, but even after the internal temperature of specimen reaching to the final temperature, somewhat prolonged softening was required to obtain the best plastic conditions. The minimum softening time for bending of 15 mm-squared silk worm oak and Korean red pine specimen was 15 and 10 minutes in the boiling treatment, and 30 and 20 minutes in the steaming treatment, respectively. 9. The optimum M.C. for bending of silk worm oak was 20 percent, and the M.C. above fiber saturation point rather degraded the bending processing property, whereas the optimum M.C. of Korean red pine needed to be above 30 percent. 10. The bending works in the optimum conditions obtained as seen in Table 24 showed that the M.B.R. of silk worm oak and Korean red pine was 80 mm and 240 mm in the boiling treatment, and 50 mm and 280 mm in the steaming treatment, respectively. Therefore, the bending processing property of the oak was better in the steaming than in the boiling treatment, but that of the pine better in the boiling than in the steaming treatment. 11. In the bending without a tension strap, the radio r/t of the minimum bending radius t to the thickness t of silk worm oak and Korean red pine specimen amounted to 16.0 and 21.3 in the boiling treatment, and 17.3 and 24.0 in the steaming treatment, respectively. But in the bending with a tension strap, the r/t of the oak and the pine specimen decreased to 5.3 and 16.0 in t he boiling treatment, and 3.3 and 18.7 in the steaming treatment, respectively. Therefore, the bending processing properties of the both species were significantly improved by the strap. 12. The effect of pin knot on the degradation of bending processing property was very severe in silk worm oak by side, e.g. 90 percent of the oak specimens with pin knot on the concave side were ruptured when bent to a 100 mm radius but only 10 percent of the other specimens with pin knot on the convex side were ruptured. 13. The changing rate in the bending radius of specimen bent to a 300 mm radius after 30 days of exposure to room temperature conditions was measured to 4.0-10.3 percent in the boiling treatment and 13,0-15.0 percent in the steaming treatment. Therefore, the degree of spring back after release was higher in the steaming than in the boiling treatment. And the changing rate of moisture-proofing treated specimen by expoxy resin coating was only -1.0.0 percent. 14. Formaldehyde, 35 percent solution, and 25 percent polyethylene glycol-400 solution found no effect on the plasticization of the both species, but saturated urea solution and 25 percent ammonium hydroxide solution found significant effect in comparison to non-treated specimen. But the effect of the treatment with chemicals alone was inferior to that of the steaming treatment, and the steaming treatment after the treatment with chemicals improved 10-24 percent over the bending processing property of steam-bent specimen. 15. Three plasticity coefficients - load-strain coefficient, strain coefficient, and energy coefficient - were evaluated to be appropriate for the index of bending processing property because the coefficients had highly significant correlation with the bending radius. The fitness of the coefficients as the index was good at load-strain coefficient, energy coefficient, and strain coefficient, in order.

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