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Thermophilic Hydrogen Production from Microbial Consortia Using PVDF Membrane Bioreactor (PVDF 여과막 생물막 반응기를 이용한 혐기 세균 복합체의 고온 수소생산)

  • Oh, You-Kwan;Lee, Dong-Yeol;Kim, Mi-Sun
    • Transactions of the Korean hydrogen and new energy society
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    • v.18 no.3
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    • pp.223-229
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    • 2007
  • 여과막 생물반응기를 이용하여 $60^{\circ}C$에서 혐기 세균 복합체가 포도당으로부터 수소를 생산할 수 있는 최적조건을 연구하였다. 여과막 생물반응기는 연속교반 탱크반응기와 외부에 장착된 PVDF (polyvinylidene fluoride) 중공사막 여과장치로 구성되었다. 접종슬러지는 하수처리장 소화 슬러지조에서 얻었고, 포자형성 수소생산 미생물을 얻기 위해 $90^{\circ}C$에서 20분 간 열처리하였다. 16S rRNA PCR-DGGE(polymer chain reaction-denaturing gradient gel electrophoresis) 분석을 통해 열처리 전후의 미생물상 변화를 조사하였다. 열처리 후 DGGE 밴드의 수는 감소하였고, 주요 밴드는 Clostridium perfringens와 유사한 염기서열을 나타내었다. 운전 기간 동안 바이오가스 내 수소함량은 60%(v/v)를 유지하였고, 메탄은 검출되지 않았다. 연속교반 탱크반응기를 여과막 없이 수력학적 체류 4시간에서 운전하였을 때 공급된 포도당의 95.0%가 제거되었고, 이때 균체농도 및 수소생산속도는 각각 1.35 g cell/L 및 7.4 L $H_2$/L/day이었다. 동일한 체류시간에서 PVDF중공사막 여과장치를 장착하여 연속교반 탱크반응기를 운전하였을 때, 균체농도는 1.62 g cel/L로 증가하였고 높은 포도당 제거율(99.5%) 및 수소생산속도(8.8 L $H_2$/L/day)가 관찰되었다. 40 nm 및 100 nm의 공극크기를 가진 여과막은 균체농도 및 수소생산 측면에서 유사한 성능을 나타내었다. 여과막 생물반응기는 여과막의 반복적인 세척을 통해 30일 이상 안정적으로 운전될 수 있었다.

3D Figure Creation System Based on Content-Awareness for 3D Printing (3D 프린팅을 위한 콘텐츠 인지 기반 3D 개인 피규어 생성 시스템)

  • Lim, Seong-Jae;Hwang, Bon-Woo;Yoon, Seung-Uk;Jeon, Hye-Ryeong;Park, Chang-Joon;Choi, Jin-Sung
    • Journal of the Korea Computer Graphics Society
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    • v.21 no.3
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    • pp.11-16
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    • 2015
  • We present a system for generating 3D personalized figures. This system provides 3D figures model modification and combination functions based on the content-awareness. The integrity of the 3D model must be guaranteed at the time of slicing of the 3D model for 3D printing. In addition to this, with 3D printing, we generally have to print a hollow model in order to save money, time, and the integrity of the print. This paper proposes the automatic algorithm that creates the 3D individual figures with depth sensor and the easy UI functions for deformation, thickness adjustment, and combination of the generated 3D figures model based on the content-awareness. Our proposed method maintains the unique features of the generated 3D figures and ensures the successful 3D printing.

Prosthetic Treatment with Palatal Obturator for the Patient who had Hemimaxillectomy: Case Report (상악골 부분 절제술을 받은 환자에서 구개 폐쇄 장치를 이용한 보철치료: 증례보고)

  • Choi, Su-Jeong;Jo, Kwang-Hun;Lee, Kyu-Bok
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.3
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    • pp.337-342
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    • 2011
  • Congenital or traumatic loss on the oral and maxillary area or the loss of jaws due to the surgical excision of a tumor causes functional problems, such as masticatory and swallowing disorders, phonetic problems and psychological disorders in patients. In most cases, a prosthetic restoration is needed to resolve these problems and restore the damaged tissue and function. When loss occurs on the maxilla, foods and liquids leak into the nasal cavity, and a nasal sound can be heard due to air leakage into the removed area. In these cases, the palatal obturator can be used to improve the esthetic and functional aspects because it restores the removed area of the maxilla and closes the opened route between the oral cavity and maxillary sinus or nasal cavity. In this case report, a palatal obturator was applied to patients who had a hemimaxillectomy due to the occurrence of squamous cell carcinoma on the right maxillary area. Therefore, fundamental functions, such as phonetic and swallowing functions were restored, and the esthetic aspects of the facial profile were improved.

An Experimental Study on the Compression Behavior of the Circular and Square Tubular Steel Pipe filled with Concrete (콘크리트 충전 원형 및 각형 합성 강관 기둥의 압축 거동에 관한 실험적 연구)

  • Park, Kang-Geun
    • Journal of Korean Association for Spatial Structures
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    • v.6 no.1 s.19
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    • pp.55-63
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    • 2006
  • Concrete-filled steel columns consist of circular, square or rectangular hollow sections filled concrete. Much research has studied for the behavior of concrete-filled steel structures. The advantages from structural point of view are the triaxial confinement of the concrete within the section, and the fire resistance of the column which largely depends on the residual capacity of the concrete core. The axial capacity of a concrete-filled rectangular or circular section is enhanced by the confining effect of the steel section on the concrete which depends in the magnitude on the shape of the section and the length of the column. Buckling tends to reduce the benefit of confinement on the squash load as the column slenderness increases. In circular sections it is possible to develop the cylinder strength of the concrete. When compare with reinforced concrete columns, the concrete-filled composite column possesses much better strength and ductility in shear and generally in flexure also. Many researches are being conducted about concrete filled steel column to get these advantages in building design. In this paper it is provided to the basic experimental study of compression behavior of the circular and rectangular tubular steel pipe filled with concrete.

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Thermal Comfort of the Sports/Leisure Clothing with the Heat Storage/Reflection Function - Wearing Evaluation under the Condition of 0x00B1;1℃ and 50±5% RH - (축열/체열반사기능을 가진 스포츠 레저복의 온열쾌적성 - 0±1℃, 50±5% RH 환경에서의 착의평가 -)

  • Kim, Tae-Gyou;Song, Min Kyu;Lee, Chang Min;Kwon, Oh Kyung
    • Fashion & Textile Research Journal
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    • v.20 no.4
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    • pp.474-481
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    • 2018
  • For this study, we developed clothing in which textile materials that were excellent weather control function for the cold environment and we performed the human subject test with developed clothing to determine the thermal comfort. We used 2 clothing samples developed (A and B, hollow yarn+moisture absorption/quick drying yarn, 3 layers, high stretchable, heat reflection film and lamination treated) and a control sample (Ctrl.) for the human subject test and 8 adult males were used as a human subjects and environmental conditions of chamber were $0{\pm}1^{\circ}C$. $50{\pm}5%RH$, 0.3m/sec. The results were as follows: The average skin temperature and hand, thigh temperature of B were higher than B and Ctrl. (p<.05). The micro-climates of B were near to thermal comfort range which is $32{\pm}1^{\circ}C$ and $50{\pm}10%\;RH$. The chest temperature of B was significantly higher than others (p<.05). The relative humidity of B was lower than others and kept stable rather than others. The thermal sensation of B was near the "neutral" and was significantly different from Ctrl. (p<.01) and the weight loss of B was lower than Ctrl. (p<.05). The counting task and hand temperature was positively related and the counting task value of B and A is bigger than Ctrl. and that of A was bigger than Ctrl. (p<.05).

Usage Analysis and Design Development for Pilot Gloves (비행장갑설계를 위한 사용실태분석 및 개선안 개발)

  • Park, Ji-Eun;Jeon, Eun-Jin;Jeong, Jeong-Rim;Park, Sei-Kwon;You, Hee-Cheon;Kim, Hee-Eun
    • Fashion & Textile Research Journal
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    • v.11 no.5
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    • pp.764-770
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    • 2009
  • This study was conducted to analyze the wearing condition on gloves for pilots and to suggest the developments for pilot gloves design. This survey was performed with 99 pilots and the questionnaires included items about discomfort, materials and problems when wearing pilot gloves. The respondents felt uncomfortable on the finger tip, the hollow area of the hand and the end of thumb when they move their hands with the gloves. They replied that the finger length, palm length, and circumference of the fingers did not match well. Also they complained there was severe abrasion in the tip of the thumb, finger tips and the middle of the palm of the gloves. The result of these analyses supports the following suggestions. It is necessary to improve durability by applying the additional materials to the severely worn parts. Punching on the glove materials could improve sweat rate and ventilation, and careful washing should be accompanied to prevent the occurrence of linters and transformation after laundering. And it is needed to prepare an accurate and more diversified size system and to design the gloves fitted to the individual hands. With these in mind, it is required to propose solutions for pilot gloves with reference to the survey results in order to design appropriate pilot gloves in terms of movement, size and material. It was concluded that an analysis of the wearing condition and developments are useful for ergonomics pilot gloves design.

A bibliographic study about the meaning of Hwa and Hwa-byung (화(火) 및 화병(火病)의 의의(意義)에 관한 문헌적(文獻的) 고찰(考察))

  • Park Jing-Sung;Lyu Yeong-Soo
    • Journal of Oriental Neuropsychiatry
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    • v.8 no.1
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    • pp.183-200
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    • 1997
  • I got the following result from the bibliographic study about the meaning of Hwa(火) and Hwa- byung(火病) at the concept and the aspect of pathological and etiological factors.The results are as follows.1. The pathological characteristics of Hwa(火) mean the inflammed state, the excited mental condition and perinervous hyperfunction caused by exopathy produced by any of the six extermal etiological factors(外感六淫) and Hwa caused by interior injury(內傷火熱).2. Hwa caused by the fire emotions(五志之火); anger, gladness, contemplation, sadress, fear by menta complications brings to Hwa caused by the five viscera(五臟之火) and Hwa caused by the stagnation of the liver - energy(肝鬱之火) is the rpresentive Hwa caused by the five viscera and the six hollow organs(贓腑之火).3. A symptom caused by a pathogenic Hwa(火證) is understood in a pathological sense involved an inflammed disease and is considered as a pathological state of excess syndrome(實證) caused by exterior Hwa( 外火).4. The pathologic process of Hwa-byung(火病) as the mental disease is based upon our people's emotion; Han(恨) to be pathologized without being overcome and can be considered as the process of Hwa caused by long-term(鬱久而火化).5. Hwa-byung(火病) means a psychosomatic disorder resulting from stress reaction caused by personal relations in the climacterium.Form the above mentioned study, the meaning of Hwa(火) and Hwa-byung(火病) is set theoretically and it also needs to be maintained reserching and studying about Hwa-byung(火病) consistantly.

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Lemanea manipurensis sp. nov. (Batrachospermales), a freshwater red algal species from North-East India

  • Ganesan, E.K.;West, J.A.;Zuccarello, G.C.;de Goer, S. Loiseaux;Rout, J.
    • ALGAE
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    • v.30 no.1
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    • pp.1-13
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    • 2015
  • A new macroscopic riverine red algal species, Lemanea manipurensis sp. nov. (Batrachospermales) is described from Manipur in northeast India. It has a sparsely branched, pseudoparenchymatous thallus with a single, central axial filament that lacks cortical filaments. Spermatangia occur generally in isolated, low and indistinct patches or form an almost continuous ring around the axis. Carposporophytes project into the hollow thallus cavity without an ostiole. The most striking morphological feature is the carposporophyte with very short gonimoblast filaments having cylindrical, narrow and sparsely branched sterile filaments, the terminal cell of each branch with a single, large, elongate carpospore. The widely distributed L. fluviatilis has spherical carpospores in long branched chains. Phylogenetic analysis of rbcL sequence data and comparison with other Batrachospermales clearly show that our specimens do not align with other species of Lemanea and Paralemanea investigated thus far. Five specific names attributed in previous literature (1973-2014) to Lemanea from Manipur, L. australis, L. catenata, L. fluviatilis, L. mamillosa, and L. torulosa are rejected until critical anatomical and molecular evidence is available for specimens from the Manipur river systems. Taxa referable to Paralemanea were not confirmed for India in this study. In view of the high demand for food and medical uses of L. manipurensis in northeast India, conservation measures are needed for its long term survival. The present paper constitutes the first combined morphological / molecular study on a freshwater red alga from India.

Occurrence of Gray Mold on Prunus mume Caused by Botrytis cinerea in Korea (Botrytis cinerea에 의한 매실나무 잿빛곰팡이병 발생)

  • Kwon, Jin-Hyeuk;Kim, Won-Il;Park, Chang-Seuk
    • Research in Plant Disease
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    • v.13 no.3
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    • pp.216-219
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    • 2007
  • Gray mold caused by Botrytis cinerea occurred on Prunus mume Sieb. & Zucc. in an experimetal orchard of Gyeongsangnam-do Agricultural Research and Extension Services in Korea from 2005 to 2007. The symptoms usually started with water-soaking lesions and hollow depression on the fruit surface. The conidia of the pathogen appeared on the surface fruits. The conidia were one celled and mostly ellipsoid or ovoid in shape and were colorless or pale brown in color. The conidia were $6{\sim}17{\times}4{\sim}10{\mu}m$ in size and conidiophores were $15{\sim}30{\mu}m$ in length. The sclerotial formed abundantly on potato-dextrose agar, They were flat or irregular in shape and black in color The optimum temperature for sclerotial formation was $20^{\circ}C$. On the basis of mycological characteristics and pathogenicity test on host plants, the fungus was identified as Botrytis cinerea Persoon: Fries. This is the first report on gray mold of P. mume caused by B. cinerea by in Korea.

Integrative Modeling of Wireless RF Links for Train-to-Wayside Communication in Railway Tunnel

  • Pu, Shi;Hao, Jian-Hong
    • Journal of Korea Society of Industrial Information Systems
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    • v.17 no.2
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    • pp.19-27
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    • 2012
  • In railway tunnel environment, the reliability of a high-data-rate and real-time train-to-wayside communication should be maintained especially when high-speed train moves along the track. In China and Europe, the communication frequency around 900 MHz is widely used for railway applications. At this carrier frequency band, both of the solutions based on continuously laid leaky coaxial cable (LCX) and discretely installed base-station antennas (BSAs), are applied in tunnel radio coverage. Many available works have concentrated on the radio-wave propagation in tunnels by different kinds of prediction models. Most of them solve this problem as natural propagation in a relatively large hollow waveguide, by neglecting the transmitting/receiving (Tx/Rx) components. However, within such confined areas like railway tunnels especially loaded with train, the complex communication environment becomes an important factor that would affect the quality of the signal transmission. This paper will apply a full-wave numerical method to this case, for considering the BSA or LCX, train antennas and their interacted environments, such as the locomotive body, overhead line for power supply, locomotive pantograph, steel rails, ballastless track, tunnel walls, etc.. Involving finite-difference time-domain (FDTD) method and uni-axial anisotropic perfectly matched layer (UPML) technique, the entire wireless RF downlinks of BSA and LCX to tunnel space to train antenna are precisely modeled (so-called integrative modeling technique, IMT). When exciting the BSA and LCX separately, the field distributions of some cross-sections in a rectangular tunnel are presented. It can be found that the influence of the locomotive body and other tunnel environments is very significant. The field coverage on the locomotive roof plane where the train antennas mounted, seems more homogenous when the side-laying position of the BSA or LCX is much higher. Also, much smoother field coverage solution is achieved by choosing LCX for its characteristic of more homogenous electromagnetic wave radiation.