A Study on Hydroelastic Response of Box-Type Very Large Floating Structures

The application of very large floating structure (VLFS) to the utilization of ocean space and exploitation of ocean resources has become one of the issues of great interest in international ocean engineering field. Owing to the advantage of simplicity in structure and low cost of construction and maintenance, box-type VLFS can be used in the calm water area near the coast as the structure configuration of floating airport. In this paper, a 3D linear hydroelastic theory is used to study the dynamic response of box-type VLFS in sinusoidal regular waves. A beam model and a 3D FEM model are respectively employed to describe the dynamic characteristics of the box-type Structure in vacuum. A hydrodynamic model (3D potential theory of flexible body) is applied to investigate the effect of different dry models on the hydroelastic response of box-type structure. Based on the calculation of hydroelastic response in regular waves, the rigid body motion displacement, flexible deflection, and the short term and long term wave induced bending moments are also predicted.

Forkhead box protein A2 and T helper type 2-mediated pulmonary inflammation

The transcription factor forkhead box protein A2(FOXA2, also known as hepatocyte nuclear factor 3β or transcription factor 3β), has been found to play pivotal roles in multiple phases of mammalian life, from the early development to the organofaction, and subsequently in homeostasis and metabolism in the adult. In the embryonic development period, FOXA2 is require d for the formation of the primitive node and notochord, and its absence results in embryonic lethality. Moreover, FOXA2 plays an important role not only in lung development, but also in T helper type 2(Th2)-mediated pulmonary inflammation and goblet cell hyperplasia. In this article, the role of FOXA2 in lung development and Th2-mediated pulmonary inflammation, as well as in goblet cell hyperplasia, is reviewed. FOXA2 deletion in airway epithelium results into Th2-mediated pulmonary inflammation and goblet cell hyperplasia in developing lung. Leukotriene pathway and signal transducers and activators of transcription 6 pathway may mediate this inflammation through recruitment and activation of denditric cell during lung developments. FOXA2 is a potential treatment target for lung diseases with Th2 inflammation and goblet cell hyperplasia, such as asthma and chronic obstructive pulmonary disease.

Theoretical and Experimental Studies of a Box-Type Solar Cooker in Unfavorable Climatic Conditions

A box-type solar cooker with an inclined surface, equipped with a concentration reflector to allow maximum energy to be collected, enabled cooking tests to be carried out in the rainy season. Different thermocouples were implanted on various places of the cooker. The temperature measurements from these sensors were taken every 10 minutes. The tests presented in this article relate to the preparation of eggs and rice. The absorber temperatures during the tests exceeded 100°C. The cooking times were between 1 h 50 min and 2 h 20 min despite the numerous cloudy periods. The cooker made it possible to reach sufficient temperatures for healthy cooking of food. The results obtained for these first tests are satisfactory and very encouraging.

Analysis of MIKC^C-Type MADS-Box Gene Family in Gossypium hirsutum

MIKCC-type MADS-box genes encode transcription factors that are involved in plant developmental control and signal transduction. Few Gossypium hirsutum MADS-box genes have been reported thus far. Recently, the genome of Gossypium raimondii, considering the contributor of the D subgenome to G. hirsutum, was sequenced and provided a valuable resource to identify and analyze multiple MADS-box genes in G. hirsutum. Here we comprehensively analyzed 53 MIKCC-type MADS-box genes, including 34 newly cloned genes. Phylogenetic analysis of these genes with those from Arabidopsis and grapevine showed that the FLC and AGL12 subfamilies were absent in G. hirsutum. Proteins within a gene subfamily tended to share conserved motifs, and large differences occurred among subfamilies. Expression analysis in multiple tissues and lforal organs implied differing roles for the subfamilies in G. hirsutum. At nine loci, two or three genes co-occurred, indicating that they came from different subgenomes; these groups had similar expression patterns. The identiifcation of MIKCC-type MADS-box genes in G. hirsutum provides a valuable resource for further research into lfowering time, lfower development and ovule development in this important crop plant.

Analysis of Key Technologies in the Design of Small and Medium Span Basket Type Steel Box Tied Arch Bridge

In order to ensure the construction quality and safety of small and medium span basket type steel box tied arch bridge,this paper takes a practical project as an example to analyze the key technologies in its design process.It is hoped that this analysis can provide corresponding reference for the design and construction of this kind of arch bridge.

Effect of PWHT with Sheet-Type Ceramic Heater on Compressive Behaviors of Non-Stiffened Welded Steel Box Columns

A series of fundamental experimental investigation was conducted in order to examine the effect of PWHT by sheet-type ceramic heater on the residual stress, deformation and compressive behavior of non-stiffened welded box columns. The sheet-type ceramic heater was able to control the required temperature history for PWHT with high accuracy. The welding-induced tensile and compressive residual stresses of the specimens were reduced by 90% and 76% respectively with PWHT. Besides, PWHT could reduce the welding-induced out-of-plane deformation by 22%. It was revealed that the PWHT specimens had a slight higher stiffness than the As-welded specimens when applying monotonic static compressive load on both As-welded and PWHT specimens. They could also enhance the ultimate compressive load capacity about 32% of that of the As-welded specimens. The effectiveness of PWHT with the sheet-type ceramic heater could be confirmed.

10kV箱变改造为发电机转子护环感应加热电源的研究与应用

在某核电站汽轮发电机转子首次检修和绕组发生绝缘缺陷时,需要采用感应加热法拆除转子护环进行检查与处理。本文结合电站实际情况及护环拆装需求,经过分析与计算,按照最优的单绕组供电方案将工程建设期退役的10kV箱式变电站改造成拆装发电机转子护环所需的感应加热电源,并在两台百万千瓦级汽轮发电机的首次大修和转子绝缘缺陷处理中实现成功应用,有效保障了核电站发电机大修工期,节约了大修成本。

一种新型振弦式土压力盒的结构设计分析

在我国,岩土工程领域十分广阔,工程的应力检测、监测显得尤为重要。检测岩土基础的应力变化所用的土压力盒、土压力计种类繁多,有些土压力盒原理相同但结构多样,还有些土压力盒标定方法与实际应用完全不符。基于此,提出一种能够符合现场埋设应用的振弦式土压力盒。该设计是轮辐式工作膜在无盒状态下只接受压力传递片的压力和校准方法。

油菜B-box型锌指蛋白基因BnSTO的克隆和表达

B-box型锌指蛋白参与植物多种生长发育和非生物逆境胁迫响应过程。笔者通过RT-PCR克隆得到甘蓝型油菜2个B-box型锌指蛋白基因Bn STO-1和Bn STO-2。Bn STO-1的ORF长度为723 bp,推测编码240个氨基酸,定位于A8染色体。Bn STO-2的ORF长度为726 bp,推测编码241个氨基酸,定位于C8染色体。2个基因均由3个外显子和2个内含子构成,在氨基酸水平上的相似性达到了96.68%。系统进化分析表明Bn STO与拟南芥At STO的亲缘关系较近,同源性较高。荧光实时定量PCR结果表明Bn STO在检测的各个组织中均有表达,其中叶和蕾中的表达量最高;高盐、干旱和高温能显著诱导Bn STO-1和Bn STO-2的表达,但出现峰值的时间不同,推测2个基因均可能参与了油菜的非生物逆境胁迫响应。

箱体型正压式平板负离子抗菌陶瓷膜MBR在城市新鲜垃圾渗滤液处理应用实例

山东某垃圾焚烧厂中产生的新鲜垃圾渗滤液有机物和氨氮浓度高,同时含有多种重金属,属于难处理的废水。本工程采用气浮预处理+两级UASB+A/O+平板式MBR膜过滤+后续深度处理(纳滤+反渗透)工艺。厌氧处理阶段采用投加零价铁来提高处理效果。MBR工艺采用箱体型正压式优化结构,比传统的浸没式结构能提高膜通量和优化操作。MBR膜采用能抑菌杀菌的负离子抗菌平板陶瓷膜,具有膜通量大,缓解膜污染能力强的特点。工程运行表明,出水水质低于≤生活垃圾卫生填埋场污染控制标准≥(GB 16889-2008)表3中的标准要求,即COD≤60 mg/L,BOD_(5)≤20 mg/L,ρ(氨氮)≤8 mg/L,ρ(总氮)≤20 mg/L,ρ(SS)≤2.0 mg/L等。工程投资总成本500万左右。吨水成本将核算后为14.9元。

大豆MIKC型MADS-box基因家族分析

根据拟南芥的MIKC型MADS—box蛋白序列构建HMM（hidden markov model）模型，在大豆基因组中确定了57个MIKC型MADS-box同源基因。分子进化树分析表明，57个大豆MIKC型MADS-box基因分为14个亚类，而MIKC^＋型基因又分为两个进化支。控制花形态建成的ABCDE同源异型基因（如AP1，AG，AP3和PI等）和重要的控制开花时间的基因（如SVP和SOCl）在大豆基因组中表现出多拷贝的特征。MEME和SMART分析表明，大豆和拟南芥MIKC型MADS—box基因具有保守的MADS和K-box基序，还有一些亚类具有特异的基序。MIKC型MADS—box基因结构较为保守，多数基因具有7～8个外显子。本研究得到的MIKC型MADS—box基因为下一步研究大豆花形态建成和开花时间调控的分子机制提供了重要参考依据。

基于新材料应用的轻量化U型自卸车厢的优化仿真

自卸车是重型商用车最基础的一款专用车产品。在我国近几年的自卸车行业发展中,随着国家对环境的重视,在生产制作和使用中矩形箱结构重量大的问题日益突出,车厢结构开始由原来的矩形箱逐渐开始向U型车厢转变。文章模型采用三维软件SolidWorks造型建模,采用高效的有限元软件进行分析。模拟不同路况及装载情况下的车厢受力情况,根据分析结果从钢板材质和车厢结构方面对车厢进行优化。

俞大猷“实用性”武学思想形成的社会史阐释及当代启示——基于《剑经》的文化考察

以《剑经》为研究对象,运用文献资料、逻辑分析及历史分析等研究方法,对俞大猷武学思想在《剑经》中的“实用性”表现进行分析并阐释其形成的社会史原因。研究表明,俞大猷武学思想的“实用性”主要表现在《剑经》中融入军事思想的格斗战术、杀伤性强的技术和拍位理念等方面;俞大猷“实用性”武学思想形成的历史社会动因有三:其一,长期在军事前线的殊死战斗为俞大猷“实用性”武学思想的形成奠定了实践基础;其二,闽南社会环境影响下的务实尚武之民风为俞大猷“实用性”武学思想的形成提供了思想基础;其三,“知行合一”学说及其对个人“批判性思维”的塑造为俞大猷“实用性”武学思想的形成提供了理论基础。最后在对《剑经》进行文化考察的基础上,得出当代武术要想获得良性传承与发展,应以国家需求为价值导向,切实维持拳种的风格特征,同时武者在此过程中也要做到“知行合一”的启示。

箱式变电站外围恒温网络入侵的动态检测研究

变电站外围恒温网络节点关联较弱,易受外界入侵。为此,提出基于深度信念网络(DBN)的箱式变电站外围恒温网络入侵动态检测方法。首先,对恒温网络数据实施类型转换和归一化处理,将Nominal类型转换为Numeric类型,以避免转换数据维度变高。然后,利用非线性迭代偏最小二乘法对恒温网络数据实施特征提取和分类处理,以增强入侵信号的聚类。最后,结合DBN模型并利用核极限学习机(KELM)分类算法,对恒温网络的入侵数据实施检测。试验结果表明,该方法的模型训练准确率最高为90%;当迭代次数达到200次时,训练时间为10.35 s;网络入侵检测效率高且检测结果误差分数小,平均误差分数为1%。该方法对各样本的网络入侵检测率稳定,有利于网络入侵检测的实际应用。

钢箱梁桁架式纵隔板疲劳开裂弹性阻尼支撑处治技术

针对钢箱梁桁架式纵隔板中出现的早发性、多发性、再发性疲劳开裂病害,分析桁架式纵隔板病害原因,基于能量法,提出将端部刚接斜腹杆变为端部铰接的弹性阻尼支撑处治技术。研制弹性阻尼支撑装置(Elastic-Damping Support Device,EDSD),将斜腹杆局部切除并安装EDSD,通过EDSD中设置的弹性阻尼单元耗散外部荷载输入结构的大部分能量,保障结构在长期车辆荷载等作用下的安全性和正常使用性能。结合某斜拉桥钢箱梁桁架式纵隔板疲劳开裂处治需求,开展了该处治技术实桥应用,并对其进行有限元分析及实桥监测。结果表明:钢箱梁内斜腹杆局部改造安装EDSD后可大幅降低斜腹杆应力水平,有效降低斜腹杆疲劳易损部位开裂风险,增加疲劳寿命;安装EDSD的斜腹杆上的既有裂缝均无扩展。

钢结构箱形旋转楼梯制作技术

在钢结构箱形旋转楼梯的生产制作过程中,先对图纸进行分析,建立BIM三维实体模型,在实体模型上找出尺寸控制点,绘制胎具放样图,搭设旋转楼梯专用组焊胎具,同时使用基于PKPM系统下的学思软件进行排版,通过对旋转楼梯生产过程中的下料尺寸、坡口角度、装配精度和焊接参数等对产品质量有着关键影响的因素进行严格控制,有效保证了钢结构箱形旋转楼梯的制作质量。

装配式模块箱型建筑在应急救援装备领域的研发与应用

本文探讨了装配式模块箱型建筑在应急救援装备领域的研发和应用,重点分析了其在设计、实施和技术创新方面的主要挑战与机遇。文章首先介绍了装配式模块箱型建筑国内外政策支持背景,明确了定义与特点,然后分析了典型的应用案例,阐明了应急救援装备领域的需求,文章提出了装配式模块箱型建筑研发的重点和创新方向,旨在为未来相关领域的发展提供参考和指导。

基于红外图像处理的箱式变压器组件检测研究

为解决高原风电箱变巡视问题,减少巡视工作量,提高设备运行稳定性,针对基于红外图像处理的箱式变压器组件检测技术展开研究。构建YOLOv8模型作为本文实验的主要算法,在红外图像基础上,通过特征提取、目标检测头部网络、位置预测等步骤,设计检测算法,配置实验参数,训练模型。最后的实验结果表明,YOLOv8n模型mAP达到95.1%,在实验设备上识别速度达到0.35 s,与YOLOv3识别速度相比提升了74%,证明了YOLOv8算法在实际运用中可行性和有效性。

面向制造和装配的箱体类零件设计开发

箱体类零件作为产品的主体结构,将直接影响产品性能、寿命、体验、成本等核心竞争力。在竞争日趋激烈的现代制造业,优秀的设计决定了产品的上限。文章针对箱体类零件的设计面向制造和装配,将制造风险的规避、贯彻先进柔性制造、降低产品成本等可操作性强的设计理念进行综合分析与应用,在有限的设计周期内最大化产品力。

4MZ-4自走箱式采棉机的研制与试验

为满足不同种植行距下的棉花采收需要,研制了4MZ-4自走箱式采棉机,该机具有采收行距可调的特点,经田间试验验证,作业过程中的平均采净率为95.1%,平均含杂率为6.8%,平均撞落棉损失率为1.65%,平均籽棉含水率增加值为2%,通过试验证明该机的性能优良,各方面均能够满足采收的作业指标需求。