• Title/Summary/Keyword: natural form

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Bonding Performance of Maltodextrin and Citric Acid for Particleboard Made From Nipa Fronds

  • Santoso, Mahdi;Widyorini, Ragil;Prayitno, Tibertius Agus;Sulistyo, Joko
    • Journal of the Korean Wood Science and Technology
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    • v.45 no.4
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    • pp.432-443
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    • 2017
  • Maltodextrin and citric acid are two types of natural materials with the potential as an eco-friendly binder. Maltodextrin is a natural substance rich in hydroxyl groups and can form hydrogen bonds with lignoselulosic material, while citric acid is a polycarboxylic acid which can form an ester bond with a hydroxyl group at lignoselulosic material. The combination of maltodextrin and citric acid as a natural binder materials supposed to be increase the ester bonds formed within the particleboard. This research determined to investigate the bonding properties of a new adhesive composed of maltodextrin/citric acid for nipa frond particleboard. Maltodextrin and citric acid were dissolved in distillated water at the ratios of 100/0, 87.5/12.5, 75/25 and 0/100, and the concentration of the solution was adjusted to 50% for maltodextrin and 60% citric acid (wt%). This adhesive solution was sprayed onto the particles at 20% resin content based on the weight of oven dried particles. Particleboards with a size of $25{\times}25{\times}1cm$, a target density $800kg/m^3$ were prepared by hot-pressing at press temperatures of $180^{\circ}C$ or $200^{\circ}C$, a press time of 10 minute and board pressure 3.6 MPa. Physical and mechanical properties of particleboard were tested by a standard method (JIS A 5908). The results showed that added citric acid level in maltodextrin/citric acid composition and hot-pressing temperature had affected to the properties of particleboard. The optimum properties of the board were achieved at a pressing temperature of $180^{\circ}C$ and the addition of only 20% citric acid. The results also indicated that the peak intensity of C=O group increased and OH group decreased with the addition of citric acid and an increase in the pressing temperature, suggesting an interreaction between the hydroxyl groups from the lignocellulosic materials and carboxyl groups from citric acid to form the ester groups.

Aesthetic Value of the Neoclassic Style in Eighteenth to Nineteenth Century Fashion ($18\~19$세기 복식에 나타난 신고전주의 양식의 미적 가치)

  • Ham Youn-Ja
    • Journal of the Korean Society of Costume
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    • v.55 no.6 s.96
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    • pp.125-140
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    • 2005
  • The purpose of this study is to define the special characteristics of the neoclassic style in eighteenth to nineteenth century fashion. Researching into philosophy and aesthetics in eighteenth to nineteenth century, the characteristics of the neoclassic style in fashion is considered the clarity of form, the utility of function, and the sensuality combined with body. The results of this study are as follows: The clarify of form is found in geometric form based on anatomical truth of the human body in relation with rational and scientific thoughts. The utility of function is found in simple and suitable construction considering purely practical purpose of dresses. The sensuality combined with body is found in natural silhouette dress alluding naked body in connection with Rousseau' naturalism. Understanding aesthetic value of the neoclassic style will help to develop fashion designs associated with neoclassical forms.

On the Mater and Form of Landscape -by the case of the Grotto Sokgulam- (경관에 개재된 내용과 형식의 해석 -석굴암 조영을 통하여 본 석 굴형식과 신라의 동향문화성을 중심으로-)

  • 정기호
    • Journal of the Korean Institute of Landscape Architecture
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    • v.19 no.2
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    • pp.23-31
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    • 1991
  • In this paper, based on the thought of the place, I tried to define the meaning of th place and interprete its landscape. The landscape of the mt. Toham with its Grotto-temple "Sokgulam" is the major object of it. The "matter and form" of the Sokgulam realizes the archetypal meaning of the grotto, birth or place of the birth, in a concrete picture. The aesthetics of the Sokgulam, the mater and form in the work of arts, comes out light harmonious with the elements: "grotto", the new foreign element of the architectural style and "orientation", the old domestic one of the Shilla that presented itself at the Chomsongdae, a kind of observatory. The interrelation of the old and new elements in work of the Sokgulam shows us also a thought as an opinion of the transference to say: the matter of the traditional subject, "grotto" and the form makes the abstract matter concretely in sight, by receiving the natural happening of the sunrise at the winter solstice.

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A Study on Permanent Wave Form According to the Reductant (퍼머넨트 웨이브의 형태 변화에 미치는 환원제의 영향)

  • Bea, Young-Sil
    • Fashion & Textile Research Journal
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    • v.7 no.6
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    • pp.641-649
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    • 2005
  • This study is to make pH 9 reduction by adding NaOH to 1, 3, 5, 7, 9, 11% solution of thioglycollic acid, cysteine, cysteamin, to add it on helically winded natural hair and colored hair and leave them for 20, 40, 60 minutes, to add $NaBrO_3$ oxidant for 15 minutes and to compare and analyze the wave form. This study showed the results of permanent using thioglycollic acid, cysteine, cysteamin. In the permanent wave form according to the kind of reductant, concentration, and processing time, there were a little difference between thioglycollic acid and cysteine. But cysteamine not only showed apparent difference but also formed strong and elastic wave. The permanent wave is affected by the diagonosis of hair, the choice of permanent solution and the processing time. Therefore the scientific diagonosis of hair is to be considered first of all. By choosing the kind of solution, the concentration and the processing time according to the results of hair diagonosis and wave form, we can prevent the lengthening and damage of hair.

Bulk graphite: materials and manufacturing process

  • Lee, Sang-Min;Kang, Dong-Su;Roh, Jea-Seung
    • Carbon letters
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    • v.16 no.3
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    • pp.135-146
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    • 2015
  • Graphite can be classified into natural graphite from mines and artificial graphite. Due to its outstanding properties such as light weight, thermal resistance, electrical conductivity, thermal conductivity, chemical stability, and high-temperature strength, artificial graphite is used across various industries in powder form and bulk form. Artificial graphite of powder form is usually used as anode materials for secondary cells, while artificial graphite of bulk form is used in steelmaking electrode bars, nuclear reactor moderators, silicon ingots for semiconductors, and manufacturing equipment. This study defines artificial graphite as bulk graphite, and provides an overview of bulk graphite manufacturing, including isotropic and anisotropic materials, molding methods, and heat treatment.

A Study on the Vernacular Dwellings in Noksan area, Kinhae (김해녹산지역 전통주거의 조사연구)

  • KyungTaiSeo
    • Journal of the Korean housing association
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    • v.4 no.1
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    • pp.5-16
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    • 1993
  • This paper tries to find out the characteristics of the vernacular dwellings in Noksan area which has been a part of Kaya cultural realm. Through the analyses of its environments and several practical unit plans. The characteristic of the vernacular dwellings in thes arer are as below. The dwellings has been transfigured form [Omaksari] hut which is generally the smallest house form in Korea. The noticeable vernacular hut in this area is smallest 4-kan double-wing plan which is irregular 전 shape, but they call it single wing and 2-kan plan. Leed which can be obtained easily in thes area is used on roof and in wall. Timbers used in constrution are very slim or rather weak, but they were treated carafully. The chimney form in this area seems the results of minimizing of their being from the invasion of Japanese pirate, but also it seems an effective method of heat control. In conclusion, we cannot deny that the house form of this area seems affected by its exclusive natural and social environments.

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Spatial Distribution Pattern of Users by the Types of Use Activity at Lawn Areas in Park (공원잔디공간의 이용활동유형별 공간분포특성에 관한 연구)

  • 암봉훈
    • Asian Journal of Turfgrass Science
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    • v.10 no.1
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    • pp.13-20
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    • 1996
  • This study was carried out to investigate the characteristics of spatial distributon patterns of users by each type of recreational activities at lawn areas in the parks. Study sites were lawn areas at Kyungju World and Seorabul Plaza in Bomun Resort Complex in Kyungju, Korea. Space types by each recreation activities are Repose Type, Sports Type, Play Type and Strolling Type. Main results are as follows ; 1. Sport Type activities were mainly distributed at the central areas of each lawn areas. 2.The density of Sports Type activities were affected by the form of lawn areas. For natural control of excess dynamic activities, Complex Form has more advantage in the distribution of dynamic activities. So, as the form of lawn areas in the parks, complex form is more desirable. 3.Repose Typo activities were distributed at marginal areas of lawns and surrounding woods. These, the static activities, were affected by Edge Effect in spatial distribution of activities. 4.Play Typo activities also were distributed at marginal areas of lawns. It was also affected by Edge Effect in spatial distribution. 5.Strolling Type activities were distributed evenly over all lawn areas.

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A Study on the Experiential Response of Short-Form Video Users

  • Lim, Dong Kyun
    • International journal of advanced smart convergence
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    • v.10 no.4
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    • pp.273-277
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    • 2021
  • As society gradually enters a virtual, non-face-to-face society, the use of online content is increasing as well. In particular, as smartphones are thoroughly established in our daily life, the platforms of webtoons, mobile broadcasting, and education are shifting from personal computers to smartphones. Recently, the development of the Over-The-Top media service (OTT service) enabled streaming services of various media contents through the internet and activation of IPTV. Therefore, the rapid increase of popularity of short-form content is a natural phenomenon with smartphone platforms with fast, improvised, and endless communication. Lately, TikTok became the favored platform with prosumers, defined as people who are both producers and consumers. In this study, I studied the experiential response of YouTube and TikTok users as representative examples of a short-form content platform developed after the 2000s, the flourishing years of digital content with a length of 30 seconds.

EPD Thick Film Formation of Ceramic Powder Materials (세라믹 분말재료의 EPD 후막형성 기술)

  • Soh, Dea-Wha;Jeon, Yong-Woo
    • Journal of the Speleological Society of Korea
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    • no.75
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    • pp.49-54
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    • 2006
  • Electrophoretic Deposition (EPD) is the most convenient technology to deposit natural or oxide powders of nonconductive materials in alcoholic suspension solution with adding electrolyte of iodine to form ceramic thick film on metal substrate under applied electric field with double electric layer between electrode and metal substrate. In this research work, the important parameters and technical ways were studied to form EPD thick films of typical oxide ceramics of Al2O3, YBCO and tourmaline powders.

The Chiroptical Properties and Absolute Configuration of 28-nor-$\beta$-amyrins

  • Woo, Won-Sick
    • Archives of Pharmacal Research
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    • v.14 no.2
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    • pp.160-164
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    • 1991
  • The existence in nature of two isomers of 28-nortriterpenes is known. One is normal D/E cis form and the other is $17\alpha$-hydrogen D/E trans form. Since the latter cannot exist with ring D in the chair conformation, the chiroptical method is not applicable to determination of the absolute configuration. The stereochemical assignment would now be made by NMR data. Confirmation of this view could be provided by the synthesis of $3\beta, 21\beta-{dihydroxy-16-keto-28-nor-17}\alpha, \;18\beta-{olean-12-ene}$ as a model compound.

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