• Title/Summary/Keyword: fan effect

Search Result 571, Processing Time 0.024 seconds

Prevention of Barn Rot during Curing of Burley Tobacco. II. Effect of Curing Conditions and Supplemental Heat. (버어리종 잎담배 건조시 부패방지 II. 건조조건과 보조화력의 영향)

  • 배성국;임해건;한철수
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.34 no.4
    • /
    • pp.331-334
    • /
    • 1989
  • This studies were carried out to investigate the effects of the management of curing barn and the use of supplemental heat on prevention of barn rot during the rainy season. The managemental methods of curing barn were combined with hanging spaces ranged from 15cm to 30cm and ventilating conditions. The supplemental heat was applied with oil burner and oil fan heater. Barn rot was reduced in the wider hanging spaces, and the effects of hanging spaces was larger with ventilating during curing. Barn rot decreased by ventilating condition than non-ventilation. The use of supplemental heat dropped to lower relative humidity in curing barn. Supplemental heat and forced-air movement greatly reduced barn rot in comparison with tobacco cured under natural conditions.

  • PDF

IpCSB+ - tree : An Enhanced Main Memory Index Structure Employing the Level Prefetching Technique (레벨 프리페칭 기법을 이용한 향상된 주기억장치 상주형 색인구조)

  • Hong Hyun-Taek;Kang Tae-Ho;Yoo Jae-Soo
    • Journal of Internet Computing and Services
    • /
    • v.4 no.6
    • /
    • pp.75-86
    • /
    • 2003
  • In main-memory resident index structures, secondary cache misses considerably have an effect on the performance of index structures. Recently, several main-memory resident index structures that consider cache have been proposed to reduce the impact of secondary cache misses. However they still suffer from full secondary cache misses whenever visiting each level of a index tree, In this paper, we propose a new index structure that eliminates cache misses even when visiting each level of index tree. The proposed index structure prefetches the grandchildren of a current node. The basic structure of the proposed index structure is from CSB+-tree that uses the concepts of the node group to increase fan-out. However the insert algorithm of the proposed index structure reduces the cost of a split significantly, Also, we show the superiority of our algorithm through various performance evaluation.

  • PDF

Brain Activation Associated with Set Size During Random Number Generation (무선열 생성과제에서 반응후보 수에 따른 뇌활성화 양상)

  • Lee, Byeong-Taek;Kim, Cheong-Tag
    • Korean Journal of Cognitive Science
    • /
    • v.19 no.1
    • /
    • pp.57-74
    • /
    • 2008
  • This study aimed to investigate the preferential brain activations involed in the set size during random number generation (RNG). The BNG condition gave more increased activations in the anterior cingulate cortex (ACC), inferior frontal gyrus (IFG), inferior parietal lobule (IPL), and superior temporal gyrus (STG) than the simple counting condition, which was a control rendition. When the activations were compared by the small set size condition versus the large set size condition, broad areas covering tempore-occipital network, ACC, and postcentral gyrus were more highly activated in the small set size condition than in the large set size condition, while responses of areas including medial frontal gyrus, superior parietal lobule, and lingual gyrus were more increased in the large set size condition than in the small set size condition. The capacity hypothesis of working memory fails to explain the results. On the contrary, strategy selection hypothesis seems to explain the current observations properly.

  • PDF

The effect of radial cracks on tunnel stability

  • Zhou, Lei;Zhu, Zheming;Liu, Bang;Fan, Yong
    • Geomechanics and Engineering
    • /
    • v.15 no.2
    • /
    • pp.721-728
    • /
    • 2018
  • The surrounding rock mass contains cracks and joints which are distributed randomly around tunnels, and in the process of tunnel blasting excavation, radial cracks could also be induced in the surrounding rock mass. In order to clearly understand the impact of radial cracks on tunnel stability, tunnel model tests and finite element numerical analysis were implemented in this paper. Two kinds of materials: cement mortar and sandstone, were used to make tunnel models, which were loaded vertically and confined horizontally. The tunnel failure pattern was simulated by using RFPA2D code, and the Tresca stresses and the stress intensity factors were calculated by using ABAQUS code, which were applied to the analysis of tunnel model test results. The numerical results generally agree with the model test results, and the mode II stress intensity factors calculated by ABAQUS code can well explain the model test results. It can be seen that for tunnels with a radial crack emanating from three points on tunnel edge, i.e., the middle point between tunnel spandrel and its top with a dip angle $45^{\circ}$, the tunnel foot with a dip angle $127^{\circ}$, and the tunnel spandrel with $135^{\circ}$ with tunnel wall, the tunnel model strength is about a half of the regular tunnel model strength, and the corresponding tunnel stability decreases largely.

Expression and Prognostic Roles of TRPV5 and TRPV6 in Non-Small Cell Lung Cancer after Curative Resection

  • Fan, Hong;Shen, Ya-Xing;Yuan, Yun-Feng
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.6
    • /
    • pp.2559-2563
    • /
    • 2014
  • Purpose: We investigated the expression of epithelial $Ca^{2+}$ channel transient receptor potential vanilloid (TRPV) 5 and 6 in non-small-cell lung cancer (NSCLC) and assessed their prognostic role in patients after surgical resection. Materials and Methods: From January 2008 to January 2009, 145 patients who had undergone surgical resection of NSCLCs were enrolled in the study. Patient clinical characteristics were retrospectively reviewed. Fresh tumor samples as well as peritumor tissues were analyzed for TRPV5/6 expression using immune-histochemistry (IHC) and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Patients were grouped based on their TRPV5 and TRPV6 levels in the tumor tissues, followed up after surgery, and statistically analyzed to examine the prognostic roles of TRPV5 and TRPV6 on patients' survival after surgical resection of NSCLCs. Results: Using IHC, among the 145 patients who had undergone surgical resection of NSCLCs, strong protein expression (grade${\geq}2$) of TRPV5 and TRPV6 was observed in a lower percentage of primary tumor tissues than in non-tumor tissues of same patients. Similar findigns were obtained with the RT-PCR test for mRNA levels. Decreased overall mRNA levels of TRPV5 and TRPV6 were associated with a worse overall survival rate (p=0.004 and p=0.003 respectively) and shorter recurrence-free survival (p<0.001 and p<0.001 respectively). The combining effect of TRPV5 and TRPV6 on survival was further investigated using multivariate analysis. The results showed that a combination of low expression of TRPV5 and TRPV6 could be an independent predictor of poor recurrence-free survival (p=0.002). Conclusions: Decreased expression of TRPV5/6 in tumor tissues was observed in NSCLC patients and was associated with shorter median survival time after surgical resection. Combined expression of TRPV5 and TRPV6 in tumor tissues demonstrated promising prognostic value in NSCLC patients.

Simulation of an X-ray Fresnel Zone Plate with Nonideal Factors

  • Chen, Jie;Fan, Quanping;Wang, Junhua;Yuan, Dengpeng;Wei, Lai;Zhang, Qiangqiang;Liao, Junsheng;Xu, Min
    • Current Optics and Photonics
    • /
    • v.4 no.1
    • /
    • pp.9-15
    • /
    • 2020
  • Fresnel zone plates have been widely used in many applications, such as x-ray telescopes, microfluorescence, and microimaging. To obtain an x-ray Fresnel zone plate, many fabrication methods, such as electron-beam etching, ion-beam etching and chemical etching, have been developed. Fresnel zone plates fabricated by these methods will inevitably lead to some nonideal factors, which have an impact on the focusing characteristics of the zone plate. In this paper, the influences of these nonideal factors on the focusing characteristics of the zone plate are studied systematically, by numerical simulations based on scalar diffraction theory. The influence of the thickness of a Fresnel zone plate on the absolute focusing efficiency is calculated for a given incident x-ray's wavelength. The diffraction efficiency and size of the focal spot are calculated for different incline angles of the groove. The simulations of zone plates without struts, with regular struts, and with random struts are carried out, to study the effects of struts on the focusing characteristics of a zone plate. When a Fresnel zone plate is used to focus an ultrashort x-ray pulse, the effect of zone-plate structure on the final pulse duration is also discussed.

A Numerical Analysis of Hydrogen Diffusion for Hydrogen Leakage from a Fuel Cell Vehicle in a Long Road Tunnel (장대터널에서 수소연료전지 차량의 수소 누출에 대한 수소 거동의 수치해석 연구)

  • Choi, Jongrak;Hur, Nahmkeon;Lee, Moonkyu;Chang, Hyungjin;Lee, Kwangbum;Yong, Geejoong
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.23 no.6
    • /
    • pp.588-597
    • /
    • 2012
  • In the present study, the dispersion characteristics of hydrogen leakage from a Fuel Cell Vehicle (FCV) were analyzed by numerical simulation in order to assess the risk of a hydrogen leakage incident in a long road tunnel. In order to implement the worst case of hydrogen leakage, the FCV was located at the center of a tunnel, and hydrogen was completely discharged within 63 seconds. The Leakage velocity of hydrogen was adopted sub-sonic speed because that the assumption of the blockage effect of secondary device inside a vehicle. The temporal and spatial evaluation of the hydrogen concentration as well as the flammable region in a road tunnel was reported according to change of ventilation operating conditions. The hydrogen was blended by supply air form a ventilation fan, however, the hydrogen was discharged to outside in the exhaust air. It is observed that the efficiency way to eliminate of hydrogen is supply air operating condition under the hazardous hydrogen leaking incident. The present numerical analysis can be provided useful information of ventilation under the hydrogen leaking situation.

Interaction Between an Unstabilized Turbulent Boundary Layer and an Incident Oblique Shock Wave (不安定化된 亂流境界層 과 斜角入射衝擊波 와의 相互作용)

  • 이덕봉
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.9 no.2
    • /
    • pp.158-173
    • /
    • 1985
  • An experimental investigation has been made to study the interaction between and incident oblique shock wave and an unstabilized turbulent boundary layer on a solid surface downstream of a porous surface with air injection through the porous surface. The boundary layer upstream of the interaction is unstabilized by the injection and provokes a shock wave which eventually interacts with the unstabilized boundary layer after reflecting from the upper wall of the test section. Three cases having diferent upstream Mach numbers and different shock strengthes are studied. According to the level of the unstabilization, two cases are of attached boundary layers and the other one is of a separated boundary layer. The result shows that the reflected wavey system is composed of the compression wave, expansion wave fan, and recompression wave like the ordinary interaction while the separated boundary layer strengthens the reflected expansion waves. The interactions of the attached boundary layers show a similar tendency of the upstream wall pressure distribution as that of the ordinary interacton but the pressure rise rather decays in the downstream region. In case of the separated boundary layer, the wall pressure continues to rise in the downstream as opposed ot the former cases. This indicates that the interaction region spreads out widely adn the viscous effect of the separated boundary layer smoothens the abrupt pressure increase due to the shock inpingement.

Dietary Supplementation of Fat Increased Milk Fat Percentage without Affecting Ruminal Characteristics in Holstein Cows in a Warm Tropical Environment

  • Wang, A.S.;Jan, D.F.;Chen, K.J.;Yang, D.W.;Fan, Y.K.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.17 no.2
    • /
    • pp.213-220
    • /
    • 2004
  • The purpose of this experiment was to investigate the effect of the diets supplemented with lard or prilled fat ($Carolac^{(R)}$) on lactation performance, plasma constituents and ruminal characteristics of Holstein cows under a warm climate. In trial 1, 18 Holstein cows, 14 primiparas at 43 DIM and 4 multiparas at 55 DIM, were randomly assigned into six $3{\times3}$ Latin squares, in which three dietary treatments were isoproteinous but varying in energy contents and three 21 d periods. The treatments were basal diet (Control), basal diet supplemented with 2.5% lard (LD), and basal diet supplemented with 2.5% commercial Prilled fat (PF). In trial 2, three rumen canulated pregnant nonlactating Holstein cows with 550 kg average body weight were allotted into a $3{\times}3$ Latin square design with diets same as in trial 1 were fed to the cows at the level of 1.5% body weight on dry matter (DM) basis. The results indicated that the DM intake did not differ among the treatments. Milk yield and 4% FCM yield were greater (p<0.05) in PF than in Control. LD and PF resulted in greater milk fat percentage. Protein, lactose and solid contents in milk were not different among the three dietary treatments. The concentration of nonesterified fatty acids (NEFA) in plasma was significantly greater in LD and PF than that in Control. However, the concentrations of triglycerides, urea nitrogen, and cholesterol in plasma were not significantly different among the three treatments. Although the ruminal molar percentage of isobutyrate in LD and PF was greater, no significant difference was observed in ruminal pH, NH3-N concentration and VFA production among the three treatments. Diet supplemented with fat can improve milk yield and milk fat percentage without resulting in disadvantages of ruminal characteristics in cows at early lactation and under warm climate.

The Reproductive Characteristics of the Mare in Subtropical Taiwan

  • Ju, Jyh-Cherng;Peh, Huo-Cheng;Hsu, Jenn-Chung;Cheng, San-Pao;Chiu, Shaw-Ching;Fan, Yang-Kwang
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.15 no.4
    • /
    • pp.494-499
    • /
    • 2002
  • The objectives of this study were to document the reproductive traits of mares as influenced by the month of the year in Taiwan. Reproductive records, lactation traits, foal birth weight (FBW) and foal height (FBH) were collected from Holi Equine Station of Taiwan. The effects of month on these parameters were analyzed. The length of estrus (LE) was shortest in December each year. The increasing trend was recorded from January to September with a significantly (p<0.05) longer period of $12.4{\pm}0.4$ days in September than in January and February. A gradual shortening in LE was observed from September to December ($10.1{\pm}0.6$ days, p<0.05), when the shortest period of the year was observed. Mares showed signs of estrus throughout the year, but more than 80% were found in estrus during March through October. The FBW was significantly (p<0.05) affected by the breeding month of the year. The lowest foal weights were recorded in both September ($36.7{\pm}0.7$ kg) and December ($36.8{\pm}0.9$ kg), which were also significantly lower than those in other months except in March, August, and November. A trend of lower FBH from September to December (93.5-93.8 cm) than those from January to August was observed. The greatest FBH was in June (96.2 cm). Breeding months and onset of estrus of the mares exerted a significant effect on the incidence of agalactia during the lactation period. These analyses provide fundamental information on adaptive processes in respect to reproductive characteristics of mares, which indicated an extent of acclimation by these animals in subtropical Taiwan.