Torsional vibration active control of hybrid construction machinery complex shafting

Due to the coaxial connection of engine, motor and pump, the dynamic characteristics of hybrid construction machinery are changed, which generates a new torsional vibration problem of multi-power sources. To reduce the torsional vibration of the hybrid construction machinery complex shafting, torsional vibration active control was proposed. The three-mass model of coaxial shafting of hybrid construction machinery was established. The PID control and the fuzzy sliding mode control were chosen to weaken torsional vibration by controlling the motor speed and torque. The simulation results show that the fuzzy sliding mode control has 12% overshoot of the PID control when the engine torque changes. The active control is effective and can realize smooth power switch.

Shift scheduling strategy development for parallel hybrid construction vehicles

The shift scheduling system of the transmission has an important effect on the dynamic and economic performance of hybrid vehicles. In this work, shift scheduling strategies are developed for parallel hybrid construction vehicles. The effect of power distribution and direction on shift characteristics of the parallel hybrid vehicle with operating loads is evaluated, which must be considered for optimal shift control. A power distribution factor is defined to accurately describe the power distribution and direction in various parallel hybrid systems. This paper proposes a Levenberg-Marquardt algorithm optimized neural network shift scheduling strategy. The methodology contains two objective functions, it is a dynamic combination of a dynamic shift schedule for optimal vehicle acceleration, and an energy-efficient shift schedule for optimal powertrain efficiency. The study is performed on a test bench under typical operating conditions of a wheel loader. The experimental results show that the proposed strategies offer effective and competitive shift performance.

Construction and screening of suppression subtractive hybridization library of renal cell carcinoma

Objective To construct and screen the suppression subtractive hybridization (SSH) library of human renal cell carcinoma (RCC). Methods Poly A+ RNA was isolated from RCC lines 786-O(tester) and renal cell(RC) lines HK-2 ( driver), respectiely. SSH procedure was performed according to the protocol of the PCR-Select cDNA Subtraction Kit ( Clontech), and PCR products were cloned into pT-Adv vector and transformed E. coli TOP10F’. All positive clones picked out were digested and some of which were sequenced. Results The SSH library contained 362 clones with SSH cDNA fragments distributed mainly from 0.3 to 0.9 kb. Among 50 clones sequenced randomly,2 represented unknown genes and the other 48 derived from 36 known genes. Conclusion The quality of the SSH library of human RCC is reliable and is construction is the basis for further screening differentially expressed genes of RCC. 6 refs,4 figs, 1 tab.

Performance of hybrid constructed wetland systems for treating septic tank effluent

The integrated wetland systems were constructed by combining horizontal-flow and vertical-flow bed, and their purification efficiencies for septic tank effluent were detected when the hydraulic retention time （HRT） was 1 d, 3 d, 5 d under different seasons. The results showed that the removal efficiencies of the organics, phosphorus were steady in the hybrid systems, but the removal efficiency of total nitrogen was not steady due to high total nitrogen concentration in the septic tank effluent. The average removal rates of COD （chemical oxygen demand） were 89%, 87%, 83%, and 86% in summer, autumn, winter and spring, respectively, and it was up to 88%, 85%, 73%, and 74% for BOD5 （5 d biochemical oxygen demand） removal rate in four seasons. The average removal rates of TP （total phosphorous） could reach up to 97%, 98%, 95%, 98% in four seasons, but the removal rate of TN （total nitrogen） was very low. The results of this study also indicated that the capability of purification was the worst in winter. Cultivating with plants could improve the treated effluent quality fTom the hybrid systems. The results of the operation of the horizontal-flow and vertical-flow cells （hybrid systems） showed that the removal efficiencies of the organics, TP and TN in horizontal-flow and vertical-flow cells were improved significantly with the extension of HRT under the same season. The removal rate of 3 d HRT was obviously higher than that of 1 d HRT, and the removal rate of 5 d HRT was better than that of 3 d HRT, but the removal efficiency was not very obvious with the increment of HRT. Therefore, 3 d HRT might be recommended in the actual operation of the hybrid systems for economic and technical reasons.

Performance evaluation of hybrid constructed wetlands for the treatment of municipal wastewater in developing countries

In developing countries,high cost of conventional wastewater treatment is a major hindrance in its application.Constructed wetlands(CWs)offer low-cost and effective solution to this issue.The current study aimed to evaluate an innovative maneuver of CWs i.e.hybrid flow constructed wetlands(HCWs)for municipal wastewater(MWW).The HCWs included two lab scale CWs;one horizontal and one vertical,in series.Local plant species were used.HCWs were operated in both,batch and continuous mode.Batch mode was used to(1)optimize detention time and(2)find pollutants removal efficiency.Continuous operation(at batch optimized retention time)was carried out for the evaluation of mass removal rate,r(g·m-2·d-1),volumetric rate constant,Kv(per day)and areal rate constant,Ka(m·d-1).Among two local plants tested,Pistia stratiotes gave better removal efficiency than Typha.Optimum detention time in HCWs was found to be 8 days(4+4 each).The optimum COD,BOD,TSS,TKN and P removal observed for Pistia stratiotes planted HCWs was 80%,84%,82%,71%and88%respectively.Effluent standards for COD,BOD and TSS were met at optimum conditions.The values of Kaand Kv demonstrated that more removal occurred in vertical flow as compared to horizontal flow CW.

Distribution characteristics of ammonia-oxidizing bacteria in the Typha latifolia constructed wetlands using fluorescent in situ hybridization(FISH)

A molecular biology method, fluorescent in situ hybridization（FISH）, in which the pre-treatment was improved in allusion to the media of the constructed wetlands（CW）, e.g. the soil and the grit, was used to investigate the vertical distribution characteristics of ammonia-oxidizing bacteria（AOB） quantity and the relation with oxidation-reduction potential（ORP） in the Typha latifolia constructed wetlands under three different Ioadings in summer from May to September. Results showed that the quantity of the AOB decreased in the Typha latifolia CW with the increase of vertical depth. However, the AOB quantity was 2-4 times the quantity of the control in the root area. Additionally, ORP in the rhizosphere was found to be higher than other areas, which showed that Typha latifolia CW was in an aerobic state in summer when using simulated non-point sewage at the rural area of Taihu Lake in China and small town combined sewage.

Greedy Constructive Procedure-Based Hybrid Differential Algorithm for Flexible Flow shop Group Scheduling

Aiming at the flexible flowshop group scheduling problem,taking sequence dependent setup time and machine skipping into account, a mathematical model for minimizing makespan is established,and a hybrid differential evolution( HDE) algorithm based on greedy constructive procedure( GCP) is proposed,which combines differential evolution( DE) with tabu search( TS). DE is applied to generating the elite individuals of population,while TS is used for finding the optimal value by making perturbation in selected elite individuals. A lower bounding technique is developed to evaluate the quality of proposed algorithm. Experimental results verify the effectiveness and feasibility of proposed algorithm.

高职英语混合式教学模式构建及应用策略探究

近几年,以现代信息网络技术为支撑的混合式教学模式,因融合线上与线下教学的双重优势,为高职英语教学改革带来新机遇。通过构建高职英语混合式教学模式,能够在一定程度上弥补传统英语课堂教学单一性的弊端,以丰富多样的教学资源,多维度着手的教学模式,提升高职英语教学实效性。

改进迭代贪婪算法求解可重入流水车间调度问题

可重入混合流水车间是在混合流水车间的基础上增加了可重入特性,具有更高的调度复杂性。为了求解可重入混合流水车间调度问题,首先建立了调度优化模型,优化目标为最小化最大完工时间,然后提出一种带精英调整的学习型迭代贪婪算法(LIG-EA)。LIG-EA算法采用基于工件的编码方式,对重组后的染色体进行解码。种群分为精英个体和普通个体两部分,对精英个体进行精英破坏重建和基于关键工件的染色体调整,对普通个体进行学习机制的构建和普通个体的破坏重建。为提高初始种群质量,采用NEH启发式算法进行种群初始化,并针对可重入混合流水车间的重入特性,在重建操作中增加了插入有效性判断,提高了算法的运行速度。通过大量实验表明LIG-EA算法能够有效求解可重入混合流水车间调度问题。

记忆的真实性研究:一种混合理论解决方案

记忆之真是记忆哲学研究的核心议题之一。传统主张事实之真的档案观和强调意义之真的建构观均存在论证缺陷,无法全面深入地揭示记忆之真的本质。折中主义的解释方案试图调和二者之间的解释鸿沟,但仍然面临的诸多挑战。随着记忆实证科学的迅速发展,记忆哲学与科学的融合逐渐成为可能,催生了一种崭新的混合理论解释方案。混合理论通过深入探析记忆之真的哲学基底,将“记”与“忆”两个过程进行融合,并运用记忆真值表法重建“记”与“忆”的真值条件对记忆之真的内涵给予更全面、合理的论证。混合理论的解释框架可以有力地推动对记忆真实性问题的澄清,不仅有助于我们对记忆本质有更深刻的理解,也为当代记忆研究开辟了新的路径。

数字经济时代下SPOC深度混合教学模式构建及应用--以市场营销学为例

数字技术和“新商科”的发展对混合式教学提出新的需求与挑战。本文引用深度混合学习理念,融合SPOC(Small Private Online Course)教学模式,构建SPOC深度混合教学模式,并以市场营销课程为例开展实证应用研究。实践表明:SPOC深度混合教学模式通过培养高阶能力的教学目标、与时俱进地重组教学内容、开展线下线上深度混合的教学实施和采用综合性教学评价,构建四阶段教学设计流程。利用多样的信息技术,弥合理论和实践的断裂现象,有效地增加了学生深度参与,提升市场营销课程教学成效。

运输能力受限下分段建造的时空调度问题

分段建造作为船舶整个建造流程的关键环节之一,其空间资源和时间资源的动态协调性严重影响着船舶建造周期和订单交付。针对分段建造船体车间空间有限、时间组织和空间组织不协调,以及以往分段建造时空调度相关研究忽略运输能力限制等问题,以最大完工时间最小、总提前与延期惩罚值最小为优化目标,以空间大小、加工小组的异质性、运输设备的差异性与运输限制为约束条件,构建多目标时空调度模型,并基于交付期优先规则、空间定位规则和关键阻碍规则提出混合粒子群算法进行求解,最终以某船厂分段建造为例进行实例验证,结果表明:所提出的模型与算法有效降低了分段完工时间,提高了分段建造的准时化水平。研究结可为船舶智能制造以及分段制造执行系统(MES)的实际应用提供一种方法基础。

基于两性一度标准的中医内科学线上线下混合式课程建设探讨

新时代的教学模式逐渐由以教师为中心转变为以学生为中心,学生获得的知识和信息呈现出碎片化、丰富化的特点。因此,线上线下混合式教学法可以更有效地组织学生学习。在教学活动中,采用在线教学与线下教学充分结合的混合式教育,可以提高中医内科学课程的整体教学质量。作为一种基于互联网信息技术发展的新型教学方法,线上线下混合式教学在中医内科学课程中的应用取得了良好的效果。文章对“两性一度”标准的中医内科学线上线下混合式教学进行了探讨,侧重于课间在线独立预习,课堂对重点知识的深入讲解,以及在线上线下结合基础上对中医内科学知识点的讨论。

异形塔混合结构斜拉桥设计参数对成桥状态的影响研究

为研究异形塔混合结构斜拉桥相关设计参数对成桥状态的影响,进而支撑该类桥梁优化设计及施工质量控制,以某跨径组合为(2×30+2×60+2×30)m的异形塔混合结构斜拉桥为依托,建立空间有限元模型,研究主梁容重、主梁刚度、环塔刚度、拉索弹性模量、拉索初拉力、温度等参数对主梁线形、环塔线形、成桥索力的影响规律。结果表明:主梁容重、温度、拉索初拉力对成桥主梁线形的影响明显,其中,主梁容重对成桥主梁线形影响最大,其次为温度、拉索初拉力;温度、环塔刚度、拉索初拉力对环塔线形的影响明显,温度的影响最大,环塔刚度、拉索初拉力次之;拉索初拉力、温度对成桥索力的影响最为明显。

“银课”背景下基于混合式教学模式的《二手车鉴定与评估》教学改革探索与实践

面向职业教育“银课”建设课程改革,提出了课程高阶性建设的教学改革模式。以“二手车鉴定与评估”课程为例,结合“二手车鉴定与评估”的课程特点,将混合式教学模式引入课程并进行部分实践,将“项目化教学”“信息化教学”“任务驱动教学”等教学方法进行有机结合,从课程改革目标、优化课程内容、创新教学方法与授课方式及教学效果评价体系建立等方面做出尝试,旨在将其打造成教学内容质量高、教学效果好的线上线下混合式银课,并对课程重点知识点的实际建设进行了分析和说明,为“银课”课程建设改革提供了参考。

混合式金课背景下优质教学资源共建共享研究与实践——以哈尔滨金融学院量化投资课程为例

在混合式金课背景下,以哈尔滨金融学院量化投资课程为例,探索优质教学教育共建共享的路径。基于优质教学资源,明晰教学设计;基于学情分析,明确教学目标;基于互联网,搭建共建共享平台。探索混合式金课背景下量化投资课程共建共享的实践路径:以课程思政为引领,构建课程新体系;基于OBE理念,提高学生自主学习能力;实行信息化教学,充分开发优质教学资源;丰富评价主体,有效落实及时评价体系。为实现混合式金课背景下优质教学资源共建共享,提出可以合理依托社会资源,提升资源建设效率,实现平台集聚效应,完善长效机制,创建省内高校合作联盟等建议。

杂交(HYBRID)手术室建设

本文介绍了一站式杂交手术室的相关背景以及建设方法,并通过阜外医院建设杂交手术室的实例,详尽地分享了建造一站式杂交手术室的经验。

基于混合仿真试验的建筑拆除废弃物管理减碳减排效益研究

建筑拆除废弃物的增加对城市低碳可持续发展造成了严重阻碍。研究旨在探讨以“低碳化”和“无废化”为目标的建筑拆除废弃物管理政策,采用基于主体仿真和系统动力学方法的混合仿真模型,借助Anylogic软件和Java编程语言构建拆除废弃物管理的碳排放仿真试验平台,以评估不同管理策略的减废与减碳效果。研究结果显示:在建筑拆除废弃物的管理过程中,现场管理阶段的碳排放量与废弃物排放量最大,应重点改善;利益主体之间的互动有助于拆除公司向绿色拆除公司转型,提升建筑拆除废弃物管理的减排和减碳效果;源头减量、分类分拣、从量收费和宣传教育政策的组合政策效果最佳,其中的源头减量政策在减碳减排方面发挥了显著作用。研究成果有助于政府制定相关低碳管理政策,推动实现“碳中和”和“无废城市”的目标。

Rational manipulation of composition and construction toward Zn/Co bimetal hybrids for electromagnetic wave absorption

Rational manipulation of multi-metal hybrids with controllable compositions and constructions is evolv-ing as an efficacious strategy for tunable electromagnetic(EM)characteristics and EM wave(EMW)ab-sorption.Herein,a novel bi-orientation etching approach is proposed to regulate the chemical composi-tions and hybridization construction of Zn/Co hybrids,thence meeting the synergistic interaction among diverse compositions for ultra-high EMW absorption.Attributing to the stepwise heterometallic modi-fication by Zn in Co-ZIFs(Zn@Co-ZIF)and Co in Zn-ZIFs(Co@Zn-ZIF),corresponding pyrolysis products with variable Zn/Co atomic concentration and hybridization states(Zn@Co-C,Co@Zn-C)can be obtained.The Co species was confirmed to have a positive impact on both the dielectric and magnetic response,while an appropriate amount of Zn hybridization in Co substance further enhanced the synergistic ef-fect between multiple loss mechanisms,promoting the minimum reflection loss and effective absorption bandwidth of Zn@Co-C reached-34.99 dB and 5.52 GHz(2.00 mm),respectively.Finally,this work re-veals the composition and construction dependency of bimetal hybrids on EMW absorption,which can be a strong reference for developing EMAs with diverse hybridization structures.

新时代背景下化工分离工程“三微一平台”混合式教学探讨

在“互联网+教育”和“教育信息化2.0”的新时代背景下,面对新时代的使命和新工科人才的培养要求,化工专业核心课程的建设显得尤为关键,它不仅对化工人才的培养起到决定性作用,同时也为化工行业的低碳化转型提供了有力支撑。如何巧妙地融入“三微一平台”(即结合微课、微项目、微实验和在线学习平台),并充分利用网络资源与在线教学平台加强化工专业核心课程的混合式教学,已成为当前需要深入研究的课题。本文旨在通过设计“三微一平台”混合式教学模式,对化工分离工程该核心课程进行教学改革与创新,并进一步探讨化工分离工程课程建设方法和发展趋势。通过“三微一平台”的混合式教学模式,有望为化工分离工程课程注入新的活力,使其更好地适应新时代的教育需求,培养出更多具备创新精神和实践能力的优秀人才。