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A case Study of Heat Transfer from Hot Runner Mould to the Fix Platen of the Injection-moulding Machine

厦门大学学报（自然科学版） 2002年第S1期41卷 97-98页

作者： c H Tan K S Lee School of Mechanical & Manufacturing Engineering Department of Mechanical Engineering National University of Singapore Singapore Polytec hnic SingaporeSingapore

In an injection moulding process, the parallelism b et ween the tie bars of the injection moulding machine is very important as it will affect the mould closing and clamping system. In recent years, more and more ho t runner systems are being applied in the moulding industry to save material and decrease the losses of injection pressure. Heat transfer from hot runner system from the fixed half which is secured in the fix machine platen could transmit s o much heat that it may cause high temperature differential between the machine fix platen and moving platen. This will cause the tie bar to become unparallel. Part quality will be compromised and the wear of the tie bar will be excessive. Overhaul of the tie bar may be necessary after a short period of time which is c ostly. This raises the need to analyze the heat transfer from the hot runner sys tem to the machine fix platen and the methods of isolating or minimizing the hea t transfer. In this case study, a photo lens article mould was used. The mould w as built with a direct hot runner nozzle system. Heat conduction from hot runner and machine screw to machine fix platen were studied based on either using high temperature heat insulating plate put in placed between the mould and the mould ing machine fix platen or drill cooling channels in the front mould clamping pla te. The high temperature insulator is very costly as it is made out of glass re inforced polymer composite material. Experimental results were obtained and anal yzed to find the best method to minimize the unwanted heat transfer using the ch eapest and most effective method.

关键词： injection moulding cooling hot runner system i njection moulding machine platen tie bar

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Genotype specific peripheral lipid profile changes with hepatitis c therapy

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World Journal of Gastroenterology 2016年第46期22卷 10226-10231页

作者： Mark R Pedersen Amit Patel David backstedt Myunghan choi Anil b Seetharam Department of Internal Medicine Banner University Medical Center University of Arizona College of Medicine Phoenix AZ 85006 United States Department of Gastroenterology Banner University Medical Center University of Arizona College of Medicine Phoenix AZ 85006 United States Arizona State University college of Nursing and Health care Innovation banner Phoenix AZ 85006 United States Transplant and Advanced Liver Disease center University of Arizona College of Medicine Phoenix AZ 85006 United States

AIM To evaluate magnitude/direction of changes in peripheral lipid profiles in patients undergoing direct acting therapy for hepatitis c by *** Mono-infected patients with hepatitis c were treated with guideline-based DAAs at a university-based liver clinic. Patient characteristics and laboratory values were collected before and after the treatment period. baseline demographics included age, ethnicity, hypertension, diabetes, hyperlipidemia, treatment regimen, and fibrosis stage. Total cholesterol(TcHOL), high density lipoprotein(HDL), low density lipoprotein(LDL), triglycerides(TG), and liver function tests were measured prior to treatment and ETR. changes in lipid and liver function were evaluated by subgroups with respect to genotype. Mean differences were calculated for each lipid profile and liver function component(direction/magnitude). The mean differences in lipid profiles were then compared between genotypes for differences in direction/magnitude. Lipid profile and liver function changes were evaluated with Levene's test and student's t test. Mean differences in lipid profiles were compared between genotypes using ANOVA, post hoc analysis via the bonferroni correction or Dunnett *** Three hundred and seventy five patients enrolled with 321(85.6%) achieving sustained-viral response at 12 wk. 72.3% were genotype 1(GT1), 18.1% genotype 2(GT2), 9.7% genotype 3(GT3). baseline demographics were similar. Significant change in lipid profiles were seen with GT1 and GT3(ΔGT1, p and ΔGT3, p), with TcHOL increasing(+5.3, P = 0.005 and +16.1, P creasing(+12.5, P creasing(+7.4, P = 0.058 and +12.5, P creasing(-5.9, P = 0.044 and-9.80 P = 0.067). Among genotypes(ΔGT1 v. ΔGT2 v. ΔGT3, ANOVA), significant mean differences were seen with TcHOL(+5.3 v. +0.1 v. +16.1, P = 0.017) and HDL(+12.3 v. +2 v. +7.9, P = 0.040). Post-hoc, GT3 was associated with a greater increase in TcHOL than GT

关键词： Hepatitis c genotypes Lipids Metabolic syndrome

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A Matrix-Vector Operation-based Numerical Solution Method for Linear m-th Order Ordinary Differential Equations:Application to Engineering Problems

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Advances in Applied Mathematics and Mechanics 2013年第3期5卷 269-308页

作者： M.Aminbaghai M.Dorn J.Eberhardsteiner b.Pichler Institute for Mechanics of Materials and Structures Vienna University of Technology(TU Wien)Karlsplatz 13/202A-1040 ViennaAustria Linnaeus University Department of Building and Energy TechnologyL¨uckligs Plats 1S-35195 V¨axj¨oSweden

Many problems in engineering sciences can be described by linear,inhomogeneous,m-th order ordinary differential equations(ODEs)with variable *** this wide class of problems,we here present a new,simple,flexible,and robust solution method,based on piecewise exact integration of local approximation polynomials as well as on averaging local *** method is designed for modern mathematical software providing efficient environments for numerical matrix-vector operation-based *** on cubic approximation polynomials,the presented method can be expected to perform(i)similar to the Runge-Kutta method,when applied to stiff initial value problems,and(ii)significantly better than the finite difference method,when applied to boundary value ***,we use the presented method for the analysis of engineering problems including the oscillation of a modulated torsional spring pendulum,steady-state heat transfer through a cooling web,and the structural analysis of a slender tower based on second-order beam *** convergence studies provide insight into the satisfying characteristics of the proposed solution scheme.

关键词： Numerical integration polynomial approximation ODE variable coefficients initial conditions boundary conditions stiff equation

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MicroRNA (miR396) negatively regulates expression of ceramidase-like genes in Arabidopsis

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Progress in Natural Science:Materials International 2009年第6期19卷 781-785页

作者： Dongmei Liu a,b, Diqiu Yu a, a Xishuangbanna Tropical botanical Garden, chinese Academy of Sciences, Kunming 650223, china b Graduate School of the chinese Academy of Sciences, beijing 100049, china Xishuangbanna Tropical botanical Garden Chinese Academy of Sciences Kunming 650223 China Graduate School of the chinese Academy of Sciences Beijing 100049 China

MicroRNAs (miRNAs) are 21-23 nucleotide (nt), endogenous RNAs that regulate gene expression by targeting mRNAs for direct cleavage or translational repression in plants. In Arabidopsis, miR396 is encoded by two different loci (MIR396a and MIR396b) and sequence analysis suggests it may target three ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2 and Atceramidase-like 3). To demonstrate the biological function of miR396, we inserted the synthetic precursors, MIR396a or MIR396b, under the control of the enhanced cauliflower mosaic virus (caMV) 35S promoter, into a plant transformation vector (pOcA30) and transformed the constructs into Arabidopsis. The promoter increased miR396 levels by more than 2-fold, indicating appropriate maturation of the synthetic precursor MIR396a or MIR396b transcript in transgenic plants. Microarray analysis showed that the transcript levels of two ceramidase-like genes (Atceramidase-like 1, Atceramidase-like 2) were decreased by more than 2-fold and lactosylceramide 4-a-galactosyltransferase increased by more than 2-fold in transgenic plants compared with the empty vector-transformed plants. Northern blot analysis showed that the mRNA levels of the two ceramidase-like genes were significantly reduced in transgenic plants. These results indicated that miR396 probably plays a crucial role in the ceramide metabolism pathway by negatively regulating the expression of ceramidase-like genes in Arabidopsis.

关键词： miR396 miR396 precursor ceramidase ceramide

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原子核中的无规相互作用以及基态0^+主导向群表示论的推广(英文)

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高能物理与核物理 2004年第12期28卷 1307-1312页

作者： V.K.b.Kota 国家物理实验室

在相互作用玻色子模型框架下 ,使用U(N ) U(N1) U(N2 ) O(N1) O(N2 )和U(N ) O(N ) O(N1) O(N2 )群链下具有O(N1) O(N2 )对称性的无规单体及两体哈密顿量来研究给定的不可约表示(ω1ω2 )成为偶偶核基态的出现几率 ,其中 [ω1]... 详细信息

在相互作用玻色子模型框架下 ,使用U(N ) U(N1) U(N2 ) O(N1) O(N2 )和U(N ) O(N ) O(N1) O(N2 )群链下具有O(N1) O(N2 )对称性的无规单体及两体哈密顿量来研究给定的不可约表示(ω1ω2 )成为偶偶核基态的出现几率 ,其中 [ω1]和 [ω2 ]分别为O(1)和O(2 )的对称表示 .采用 5 0 0个无规矩阵系综对具有 10— 2 5个玻色子的体系进行研究后发现 ,当N1,N2 ≥ 3时 ,(ω1ω2 ) =(0 0 )出现的几率～ 5 0 % ;而 (0N)和 (N0 )出现的几率为 2 5 % .类似地 ,当N1≥ 3,N2 =1时 ,对N对偶数情形 ,ω1=0出现的几率约为75 % ;ω1=N出现的几率约为 2 5 % ;对N为奇数情形 ,ω1=0出现的几率约为 5 0 % ,而ω1=1或N出现的几率都约为 2 5 % .采用了一种推广的Hatree bose平均场理论来解释所有的这些结果 .

关键词：几率基态群表示论不可约表示玻色子类似偶偶核相互作用发现研究

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中国金丝桃属金丝桃组(藤黄科)新分类群(英文)

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植物分类学报 2005年第3期43卷 271-277页

作者： Norman K.b.RObSON Department of botany The Natural History Museum Cromwell Road London SW7 5BD

描述了中国云南北部的金丝桃属Hypericum L.(藤黄科)两个新种,即楚雄金丝桃H. fosteri N. Robson和漾濞金丝桃H. wardianum N. Robson。二者均与短柱金丝桃H. hookerianum Wight & Arn.相近。楚雄金丝桃为一地方特有种,目前仅在模式地... 详细信息

描述了中国云南北部的金丝桃属Hypericum L.(藤黄科)两个新种,即楚雄金丝桃H. fosteri N. Robson和漾濞金丝桃H. wardianum N. Robson。二者均与短柱金丝桃H. hookerianum Wight & Arn.相近。楚雄金丝桃为一地方特有种,目前仅在模式地点发现;漾濞金丝桃在缅甸东北部还有分布。二者主要以蒴果伸长,非卵状近球形,萼片无中脉而有别于短柱金丝桃。此外,将宽萼金丝桃H. latisepalum (N. Robson) N. Robson从亚种提升为种;将变异较大的纤枝金丝桃H. lagarocladum N. Robson划分为两个亚种,即叶较宽、具有开张习性的原亚种纤枝金丝桃H. lagarocladum ssp. lagarocladum和叶较窄、更为直立的新亚种狭叶金丝桃H. lagarocladum ssp. angustifolium N. Robson。

关键词：中国金丝桃属金丝桃组藤黄科新分类群新种楚雄金丝桃漾濞金丝桃

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biometric Verification System UsingHyperparameter Tuned Deep Learning Model

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computer Systems Science & Engineering 2023年第7期46卷 321-336页

作者： Mohammad Yamin Saleh bajaba Sarah b.basahel E.Laxmi Lydia Department of Management Information Systems Faculty of Economics and AdministrationKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of business Administration Faculty of Economics and AdministrationKing Abdulaziz UniversityJeddah21589Saudi Arabia Department of Management Information Systems Faculty of Economics and AdministrationKing Abdulaziz UniversityJeddahSaudi Arabia Department of computer Science and Engineering Vignan’s Institute of Information TechnologyVisakhapatnam530049India

Deep learning(DL)models have been useful in many computer vision,speech recognition,and natural language processing tasks in recent *** models seem a natural fit to handle the rising number of biometric recognition problems,from cellphone authentication to airport security *** approaches have recently been utilized to improve the efficiency of various biometric recognition *** recognition was considered the more reliable and accurate biometric detection method *** recognition has been an active research region in the last few decades due to its extensive applications,from security in airports to homeland security border *** article presents a new Political Optimizer with Deep Transfer Learning Enabled biometric Iris Recognition(PODTL-bIR)*** presented PODTL-bIR technique recognizes the iris for biometric *** the presented PODTL-bIR model,an initial stage of pre-processing is carried *** addition,the MobileNetv2 feature extractor is utilized to produce a collection of feature *** PODTL-bIR technique utilizes a bidirectional gated recurrent unit(biGRU)model to recognise iris for biometric ***,the political optimizer(PO)algorithm is used as a hyperparameter tuning strategy to improve the PODTL-bIR technique’s recognition ***-ranging experimental investigation was executed to validate the enhanced performance of the PODTL-bIR *** experimental outcome stated the promising performance of the PODTL-bIR system over other existing algorithms.

关键词： biometric verification iris recognition political optimizer deep learning feature extraction

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Influence of Some Water Physicochemical Parameters on the Distribution of black Fly (Diptera, Simuliidae) in Some Rivers in Nasarawa State, Nigeria

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Advances in Entomology 2015年第3期3卷 101-110页

作者： J. D. c. Tongjura G. A. Amuga H. b. Mafuyai b. M. Matur J. O. Olatunwa Department of biological Sciences Nasarawa State University Keffi Nigeria Department of Zoology University of Jos Jos Nigeria Department of biological Sciences University of Abuja Abuja Nigeria Mission to Support the Helpless Jos Nigeria

changes in the distribution of simuliid species and their disease transmission pattern may occur in response to climatic and environmental factors. Simuliid larvae were prospected in 34 rivers of Nasarawa State from January 2010 to December 2010. A total of 198,420 simuliid larvae collected were found to belong to six species as follows: S. damnosum s.l. (72.13%), S. adersi (24.31%), S. ruficorne (2.52%), S. cervicornutum (0.69%), S. alcocki (0.68%), and S. schoutedeni (0.17%). The monthly sample indicated continuous breeding throughout the year with peaks in July, August and September. The density of black fly larvae was estimated from samples collected on water plants per 1 dm2 of water plant surface. The study showed that both physicochemical and ecological parameters influenced the density of simuliids. correlation analysis showed a significant relationship between simuliids density and the environmental factors. Data on prevalence and distribution of simuliids in Nasarawa State are sparse and scanty. Therefore, the result of this study provides additional information on the distribution and density of simuliids in Nasarawa State, Nigeria.

关键词： Distribution Density Simuliid Nasarawa State

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桐柏-红安造山带的构造演化：从大洋俯冲／增生到陆陆碰撞

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中国科学：地球科学 2015年第9期45卷 1088-1108页

作者：刘晓春李三忠江博明中国地质科学院地质力学研究所、国土资源部古地磁与古构造重建重点实验室北京100081 中国海洋大学海洋地球科学学院青岛266100 台湾大学地质科学系中国台北106

桐柏-红安造山带位于秦岭与大别-苏鲁造山带之间，因其完好地保存了古生代增生造山体系和古生代末坤生代碰撞造山体系而成为了解华北-华南陆块之间构造演化的关键地区．近20年来的可利用研究资料表明，桐柏-红安造山带显生宙的总体构造... 详细信息

桐柏-红安造山带位于秦岭与大别-苏鲁造山带之间，因其完好地保存了古生代增生造山体系和古生代末坤生代碰撞造山体系而成为了解华北-华南陆块之间构造演化的关键地区．近20年来的可利用研究资料表明，桐柏-红安造山带显生宙的总体构造演化框架包括以下4个主要阶段：（1）早古生代（490—420Ma）大洋俯冲、岛弧增生与弧陆碰撞，从而于早古生代末在华北陆块南缘形成一个新的安第斯型大陆边缘；（2）晚古生代（340～310Ma）大洋俯冲与增生，进而在商丹-松扒断裂南侧形成变质时代相同，但变质作用类型不同的“双变质带”，即被分割的武关．龟山中级变质杂岩带和熊店高压榴辉岩带；（3）晚古生代末-早中生代（255～200Ma）大陆俯冲与陆陆碰撞，通过华南大陆岩板东深西浅的俯冲和多层次拆离／折返形成桐柏高压变质地体和红安高压／超高压变质地体；（4）晚中生代（140～120Ma）伸展、大规模岩浆侵位与构造挤出，造成桐柏-红安-大别高压／超高压变质地体最终出露地表及东宽西窄的构造格局．然而，对每一构造演化阶段的具体细节以及早期地质历史的认识方面还存在着诸多争议和（或）难以解释的问题．未来的研究除在桐柏．红安造山带继续开展深入细致的工作外，还需与西部“软碰撞”的秦岭造山带和东部“硬碰撞”的大别．苏鲁造山带的研究紧密结合，以期建立适合于整个秦岭．桐柏．红安-大别-苏鲁造山带从古生代到中生代的经典构造演化模型．

关键词：大洋俯冲增生大陆俯冲碰撞桐柏-红安造山带

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Improving Decision Tree Performance by Exception Handling

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International Journal of Automation and computing 2010年第3期7卷 372-380页

作者： Appavu Alias balamurugan Subramanian S.Pramala b.Rajalakshmi Ramasamy Rajaram Department of Information Technology Thiagarajar College of Engineering Madurai India Department of computer Science Thiagarajar College of Engineering Madurai India

This paper focuses on improving decision tree induction algorithms when a kind of tie appears during the rule generation procedure for specific training datasets. The tie occurs when there are equal proportions of the target class outcome in the leaf node＇s records that leads to a situation where majority voting cannot be applied. To solve the above mentioned exception, we propose to base the prediction of the result on the naive bayes （Nb） estimate, k-nearest neighbour （k-NN） and association rule mining （ARM）. The other features used for splitting the parent nodes are also taken into consideration.

关键词： Data mining classification decision tree majority voting naive bayes (Nb) k nearest neighbour (k NN) association rule mining (ARM)

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