• Title/Summary/Keyword: Fan performance

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A study on the effect of air velocity through a damper on smoke extraction performance in case of fire in road tunnels (도로터널 화재 시 집중배기방식의 배기포트 통과풍속이 배연성능에 미치는 영향에 관한 연구)

  • Ryu, Ji-Oh;Na, Kwang-Hoon
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.4
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    • pp.347-365
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    • 2020
  • In order to resolve traffic problems in urban areas and to increase the area of green spaces, tunnels in downtown areas are being increased. Additionally, the application of large port smoke extraction ventilation systems is increasing as a countermeasure to smoke extraction ventilation for tunnels with high potential for traffic congestion. It is known that the smoke extraction performance of the large port smoke extraction system is influenced not only by the amount of the extraction flow rate, but also by various factors such as the shape of the extraction port (damper) and the extraction air velocity through a damper. Therefore, in this study, the design standards and installation status of each country were investigated. When the extraction air flow rate was the same, the smoke extraction performance according to the size of the damper was numerically simulated in terms of smoke propagation distance, compared and evaluated, and the following results were obtained. As the cross-sectional area of the smoke damper increases, the extraction flow rate is concentrated in the damper close to the extraction fan, and the smoke extraction rate of the damper in downstream decreases, thereby increasing the smoke propagation distance on the downstream side. In order to prevent such a phenomenon, it is necessary to reduce the cross-sectional area of the smoke damper and increase the velocity of passing air through the damper so that the pressure loss passing through the damper increases, thereby reducing the non-uniformity of smoke extraction flow rate in the extraction section. In this analysis, it was found that when the interval distance of the extraction damper was 50 m, the air velocity passing through damper was 4.4 m/s or more, and when the interval distance of the extraction dampers was 100 m, the air velocity passing through damper was greater than 4.84 m/s, it was found to be advantageous to ensure smoke extraction performance.

A Study of 'Yokagura of Takachiho': A sacred Music and Dancing Performed in Takachiho, the Land of Japanese Myths (일본신화의 고장 다카치호(高千穗)의 요가구라(夜神樂))

  • Park, Weon-mo
    • Korean Journal of Heritage: History & Science
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    • v.38
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    • pp.43-107
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    • 2005
  • A ritual ceremony accompanied by a song and dance is called as Kagura in Japan. The word Kagura is originally derived from Kamukura, which means the place where spirits reside. However, later it came to refer to the whole process of the ritual ceremony itself. Through the field studies, this paper examines Takachiho-kagura, helded in Takachiho, known as the village of myths, located in northern Miyazaki-ken in Japan. Kagura takes place all night through in each and every village in Takachiho and it normally runs from the end of November when the harvest season ends until early February the next year. One ordinary house is especially chosen for this ceremony, in which Kagura performs 33 repertoires. Takachiho-kagura is sometimes called as Yokagura, since the performance takes place over-night. A song and dance is performed by ordinary village people called hoshyadong, who inherited Takachiho-kagura. Currently, the ceremony is held in more than 20 villages and designated by the government as "Important Intangible Folk Cultural Property" in Japan. Takachiho-kagura follows the example of rituals held in Sada shrine in Izumo, which is now eastern Hiroshima-ken. It is the dance using a bell, a sword, a fan, which signify Norimono and is usually combined with mask-play called as Shinno. From the shrine of village, itwelcomes the gods who defense their village, called Ujikami and other 8 million gods, called Yaoyorozunokami, in Kagurayado, where Kagura of 33 repertoires is played in order. Kagura starts from dances for attendance of the gods, Hikomai, Daidono, Kamioroshi, performs dances of Amanoiwato, the gate of heaven's cave in Japanese myths, Dazikara, Uzume, Dotori, and continues dances for the old ghosts Shibahiki, Yatsubachi mixed with acrobatics. Finally, this performance ends with dances to send off the gods, Hinomae, Gurioroshi, Gumooroshi, until the dawn the next morning. This paper explores Takachiho-kagura from the perspective of folk performance with ethnography. These days, ecstasy and oracle do not happen in Takachiho-kagura. However, it kept the old form of folk performance as Kagura held in ordinary house. Especially, in Takachiho, remarkable venue of the Japanese myths, Takachiho-kagura is developed artistically. The first field study was held in Gokamura, Iwato-zone and Ashakabe, Mitai-zone between December 6th and December 12th 1997. Afterwards, the second field study was conducted in the area of Shiba and Ashakabe from December 17th until December 19th 1997 and from December 1st until December 10th 2000.

Comparative Analysis of the Bufonis Venenum by Using TLC, HPLC, and LC-MS for Different Extraction Methods

  • Lee, Hyo-Jae;Koung, Fan-Pei;Kwon, Ki-Rok;Kang, Dae-In;Cohen, Lorenzo;Yang, Pei-Ying;Yoo, Hwa-Seung
    • Journal of Pharmacopuncture
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    • v.15 no.4
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    • pp.52-65
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    • 2012
  • Objectives: Toad venom, called Chan-Su, is a traditional Oriental medicine secreted from the auricular and the skin glands of the Bufo bufo gargarizanz Cantor or B. melanosticus Schneider and has been widely used in China, Korea and other parts of Asia for the treatment of pain, heart conditions, and cancer. We examined the concentrations of the main chemical constituents within a commercially available toad venom product and compared the levels for different extraction methods. Methods: Toad venom was extracted using either cold or hot water, ethanol (EtOH), methanol (MeOH), or ethyl acetate (EtOAc), was fractionated using precipitation or reflux, and was then analyzed using thin layer chromatography (TLC), high-performance liquid chromatography (HTLC), and liquid chroma-tography - mass spectrometry (LC-MS). Individual components were identified by comparisons of the retention times, the ultraviolet spectra, and mass spectras and differences in chemical constituents for different solvents and extraction methods are presented. Results: Components with authentic standards, including serotonin and bufodienolides (cinobufagen, bufalin, cinobufalin, and resibufogenin), were detected. The water extract of toad venom contained the greatest amount of serotonin ($75.7{\pm}0.1$ mg/g), but very small amounts of bufodienolides ($3.8{\pm}0.0$ mg/g). In contrast, the use of MeOH or EtOH extraction solutions resulted in 5-26 times higher concentrations of bufodienolides, with only trace amounts of serotonin. The relative and the absolute concentrations of the component also varied based on the extraction method; i.e., EtOH extracts yielded the greatest total amounts of bufodienolides, and EtOAc precipitation had the lowest amounts of bufodienolides. Conclusions: Toad venom consists of serotonin and several bufodienolides, and the choice of solvent to extract chemical the constituents is important as a way to enrich the purported active components for treating different conditions.

Performance Test for the Long Distance Sprayer by an Image Processing (영상처리를 이용한 광역방제기 팬의 성능실험)

  • Min, B.R.;Kim, D.W.;Seo, K.W.;Hong, J.T.;Kim, W.;Choi, J.H.;Lee, D.W.
    • Journal of Animal Environmental Science
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    • v.14 no.3
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    • pp.159-166
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    • 2008
  • This research was carried out to test and analyze capacity of the long distance sprayer fan in large livestock farmhouses. Long distance sprayer was manufactured to be able to spray a lot of water, which was a solvent for agricultural chemicals and black dye with the maximum spraying distance of 140 m and the effective spraying distance of 100 m. The spraying quantity and the distance were measured the intensity values of images within A4 papers, which absorbed the agricultural chemicals by spraying by binary image processing. These A4 papers were fixed upon the height of 1 m from soil ground at regular 10 m interval. After the A4 papers were collected and analyzed the intensity values of gray level. Gray level was ranged from 0 to 255, where 0 was black and 255 was white. A4 paper was fallen down from the stick at 10 m distance, because there were too large amount of sprayed water with black dye. Also, the paper showed low gray level at distance 30 m because of dropping lots of black water. The intensity value of gray level was showed almost less than 200 on the A4 papers between the distance 20 m and 100 m, which meant equality of spraying quantity. Additionally, it was possible to spay agricultural chemicals of until 180 m. Throughout this research, long distance sprayer could apply for preventing hoof-and-mouth disease in large livestock farmhouses.

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Development and Application of Diffusion Wave-based Distributed Runoff Model (확산파에 기초한 분포형 유출모형의 개발 및 적용)

  • Lee, Min-Ho;Yoo, Dong-Hoon
    • Journal of Korea Water Resources Association
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    • v.44 no.7
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    • pp.553-563
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    • 2011
  • According to the improvement of computer's performance, the development of Geographic Information System (GIS), and the activation of offering information, a distributed model for analyzing runoff has been studied a lot in recently years. The distribution model is a theoretical and physical model computing runoff as making target basin subdivided parted. In the distributed model developed by this study, the volume of runoff at the surface flow is calculated on the basis of the parameter determined by landcover data and a two-dimensional diffusion wave equation. Most of existing runoff models compute velocity and discharge of flow by applying Manning-Strickler's mean velocity equation and Manning's roughness coefficient. Manning's roughness coefficient is not matched with dimension and ambiguous at computation; Nevertheless, it is widely used in because of its convenience for use. In order to improve those problems, this study developed the runoff model by applying not only Manning-Strickler's equation but also Chezy's mean velocity equation. Furthermore, this study introduced a power law of exponential friction factor expressed by the function of roughness height. The distributed model developed in this study is applied to 6 events of fan-shape basin, oblong shape test basin and Anseongcheon basin as real field conditions. As a result the model is found to be excellent in comparison with the exiting runoff models using for practical engineering application.

A study on the characteristics of intelligent sawing system for band saw (띠톱기계의 스마트 톱 절삭 시스템의 특성에 관한연구)

  • LUO, luPing;DING, zelin;DING, shengxia;JIANG, Ping;FAN, li;XIAO, leihua;PAN, bosong;An, Boyoung;Eum, Younseal;Han, Changsoo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.195-204
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    • 2020
  • To help solve the problems of how to set the optimal sawing force and the optimal controller parameters for different sawing conditions, a mathematical model of a proposed sawing system was established according to the principle of sawing force control. The conventional PID control method was then used for further research of the closed-loop control of the sawing force. Finally, through simulation and experimental research, the influence rule of the controller parameters and sawing load on the control performance and the relationships between the sawing width and controller parameters (proportion coefficient) and the sawing force setting value were obtained, from which a system scheme for intelligent sawing control of a band sawing machine was proposed. The research shows that the sawing efficiency of the intelligent sawing system was 18.1 (48%) higher than that of the original sawing system when sawing a grooved section sawing material, which verifies the good control effect of the proposed scheme.

Control Algorithm Characteristic Study of Cooling System for Automotive Fuel Cell Application. (차량용 연료전지 냉각시스템 제어 알고리즘 특성 연구)

  • Han, Jae Young;Park, Ji Soo;Yu, Sangseok
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.40 no.1
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    • pp.39-45
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    • 2016
  • Thermal management of a fuel cell is important to satisfy the requirements of durability and efficiency under varying load conditions. In this study, a linear state feedback controller was designed to maintain the temperature within operating conditions. Due to the nonlinearity of automotive fuel cell system, the state feedback controller results in marginal stable under load condition from $0.5A/cm^2$ to $0.7A/cm^2$. A PWM (Pulse Width Modulation) and the modified state feedback controller are applied to control the temperature under the load condition from $0.5A/cm^2$ to $0.7A/cm^2$. The cooling system model is composed of a reservoir, radiator, bypass valve, fan, and a water pump. The performance of the control algorithm was evaluated in terms of the integral time weighted absolute error (ITAE). Additionally, MATLAB/SIMULINK$^{(R)}$ was used for the development of the system models and controllers. The modified state feedback controller was found to be more effective for controlling temperature than other algorithms when tested under low load conditions.

The Effects of Endurance Training on the Hemogram of the Horse

  • Fan, Y.K.;Hsu, J.C.;Peh, H.C.;Tsang, C.L.;Cheng, S.P.;Chiu, S.C.;Ju, J.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.9
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    • pp.1348-1353
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    • 2002
  • The purpose of this study was to evaluate the changes and readjustment capacity in the hematological characteristics of the horse during and after a prolonged training program. One pony and two hot-blooded horses were used in this study. Resting or basal blood parameters were assessed by collecting blood samples of the animals for 1 to 2 months prior to start of the training program. Each animal was subjected to arbitrary exercise for 30 min by an automatic hot trotter and was bled at 0, 15, 30, 45 (15 min of recovery), 60 (30 min of recovery), and 75 min (45 min of recovery) after onset of exercise. All animals were exercised 3 times a week over a fivemonth period. Hematological parameters including average white blood cell counts (WBC, ${\times}$$10^3$/$\mu$l), erythrocyte concentrations (RBC, ${\times}$$10^6$/$\mu$l), hematocrit (HCT, %), mean corpuscular volume (MCV, fl), number of platelets (PLT, ${\times}$$10^4$/$\mu$l), hemoglobin concentration (Hb, g/dl), mean corpuscular hemoglobin (MCH, pg), and mean corpuscular hemoglobin concentration (MCHC, g/dl) were analyzed using an automatic cell counter. All animals showed that RBC, WBC, and HCT were significantly (p<0.05) increasing from 7.09, 8.55, and 43.5 to 8.11, 9.67, and 49.5, respectively, during the 30 min of exercise and were back to or lower than the initial basis (resting and 0 min) 30 min after exercise. However, no significant differences were detected in MCV (50.3-51.3 fl), MCH (17.2-17.4 pg), and MCHC (33.7-34.4 g/dl) values (p>0.05) regardless of the training periods. Similar trends were observed after 1, 3, 4, and 5 months of training when compared to the resting state. When these parameters were analyzed by the effect of training periods (month), mean WBC concentrations significantly reduced in the fourth and fifth month after onset of training compared to that in resting condition or the first month of training program (p<0.05). The RBC values elevated at the second month (9.40) and reaching a significantly low level (p<0.001) at the fifth month (8.62) after training compared to the first month of training (7.89). In conclusion, a mild training program enhances blood parameters gradually in both the horse and the pony. Therefore, an optimized training program is beneficial in promoting the endurance performance of the horse.

Genetic Status of ESR Locus and Other Unidentified Genes As sociated with Litter Size in Chinese Indigenous Tongcheng Pig Breed after a Long Time Selection

  • Zhu, M.J.;Yu, M.;Liu, B.;Zhu, Z.Z.;Xiong, T.A.;Fan, B.;Xu, S.P.;Du, Y.Q.;Peng, Z.Z.;Li, K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.5
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    • pp.598-602
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    • 2004
  • The Tongcheng pig breed is a famous Chinese indigenous breed. The Ministry of Agriculture of China has filed it as 1 of 19 national key conservation breeds selected from more than 100 Chinese indigenous pig breeds in 2000. In order to improve the reproductive performance, it has been intensively selected to increase the litter size for about 10 years. The population randomly sampled from conservation nucleus of eight families in the Tongcheng pigs was genotyped for identification of their estrogen receptor locus polymorphisms with the PCR-RFLPs method. Only AB heterozygotes and BB homozygotes were detected, and $X^2$ test demonstrated that the locus was in disequilibrium at a significant level (p<0.05). In the present paper, the litter sizes in different parities were regarded as different traits. Holistic status of other unspecific and unidentified genes was estimated by using the statistical methods. Coefficients of kurtosis and skewness showed that the litter size still presented segregating characteristic in the 2nd, 5th, 7th, 8th and 9th parities. Analysis of homogeneity of variance between families confirmed the results for the 5th, 7th and 8th parities. The heritability of litter size for the 1st to 10th parities was estimated with paternal half-sib model and individual estimated breeding values (EBVs) were evaluated by a single trait animal model as well. We found that the averages of EBVs for litter size in each parity did not differ significantly between genotypes, despite the significant difference for original phenotype records in the 3rd, 4th and 5th parities (p<0.05 or p<0.01). The results may be explained by the deduction that the polymorphisms of ESR locus are no longer the important genetic base of litter size variation when the frequency of allele B accumulated in the experience of selection procedure, and further conferring that there exist special genes associated with litter size in the recent Tongcheng pigs population can be made.

Investigation of PCR-RFLPs within Major Histocompatibility Complex B-G Genes Using Two Restriction Enzymes in Eight Breeds of Chinese Indigenous Chickens

  • Xu, R.F.;Li, K.;Chen, G.H.;Qiang, B.Y.Z.;Mo, D.L.;Fan, B.;Li, C.C.;Yu, M.;Zhu, M.J.;Xiong, T.A.;Liu, Bang
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.7
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    • pp.942-948
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    • 2005
  • New polymorphism of major histocompatibility complex B-G genes was investigated by amplification and digestion of a 401bp fragment including intron 1 and exon 2 using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) technique with two restriction enzymes of Msp I and Tas I in eight breeds of Chinese indigenous chickens and one exotic breed. In the fragment region of the gene, three novel single nucleotide polymorphisms (SNPs) were detected at the two restriction sites. We found the transition of two nucleotides of A294G and T295C occurred at Tas I restriction site, and consequently led to a non-synonymous substitution of asparagine into serine at position 54 within the deduced amino acid sequence of immunoglobulin variable-region-like domain encoded by the exon 2 of B-G gene. It was observed at rare frequency that a single mutation of A294G occurring at the site, also caused an identical substitution of amino acid, asparagine 54-to-serine, to that we described previously. And the transversion of G319C at Msp I site led to a non-synonymous substitution, glutamine 62-to-histidine. The new alleles and allele frequencies identified by the PCR-RFLP method with the two enzymes were characterized, of which the allele A and B frequencies at Msp I and Tas I loci were given disequilibrium distribution either in the eight Chinese local breeds or in the exotic breed. By comparison, allele A at Msp I locus tended to be dominant, while, the allele B at Tas I locus tended to be dominant in all of the breeds analyzed. In Tibetan chickens, the preliminary association analysis revealed that no significant difference was observed between the different genotypes identified at the Msp I and Tas I loci and the laying performance traits, respectively.