Design and Site Experiment of Groyne in Bore Surging Area of Qiantang River

The groyne has been used widely in bank protection and river regulation. The plane layout and structural style of groyne are closely related to the stability of the groyne itself and the effect of bank protection. In this paper, based on the preliminary summary of the design of bank protection in the bore surging area of Qiantang River, some problems regarding the structure of groyne are pointed out and an improved plan is put forward. Site experiment was carried out combined with an emergency repair. The results of the experiment indicate that the improved project is reliable and successful.

Calculating buoy response for a wave energy converter-A comparison of two computational methods and experimental results

When designing a wave power plant, reliable and fast simulation tools are required. Computational fluid dynamics （CFD） software provides high accuracy but with a very high computational cost, and in operational, moderate sea states, linear potential flow theories may be sufficient to model the hydrodynamics. In this paper, a model is built in COMSOL Multiphysics to solve for the hydrodynamic parameters of a point-absorbing wave energy device. The results are compared with a linear model where the hydrodynamical parameters are computed using WAMIT, and to experimental results from the Lysekil research site. The agreement with experimental data is good for both numerical models.

Passive walker that can walk down steps:simulations and experiments

A planar passive walking model with straight legs and round feet was discussed. This model can walk down steps, both on stairs with even steps and with random steps. Simulations showed that models with small moments of inertia can navigate large height steps. Period-doubling has been observed when the space between steps grows. This period-doubling has been validated by experiments, and the results of experiments were coincident with the simulation.

Optimization of corn-stalk skin flake-wood shaving composite technology

We focused on the optimization of corn-stalk skin flake-wood shaving composite technology. We studied the effects of material-mixture ratio, glue content, hot- pressing temperature, and hot-pressing time on the appear- ance, physical, and mechanical properties of the composite by the orthogonal experiment method. Our findings yielded highly significant results in all three cases： the effects of the material-mixture ratio on 2 h of thickness swelling （2hTS） and the modulus of rupture （MOR）; the effects of glue con- tent on 2hTS, internal bond strength, and modulus of elas- ticity （MOE）; and the effects of hot-pressing temperature on MOR and MOE. Product optimization is achieved when the ratio of corn stalk skin flake to wood shaving is 3：7, the glue content is 12 %, the hot-pressing temperature is 150 ℃, and the hot-pressing time is 4.5 min.

Environmental archaeology on Longshan Culture （4500-4000 aBP） at Yuhuicun Site in Bengbu, Anhui Province

Based on the samples collected from the west wall of the ABYT2004 at Yuhuicun Site in Bengbu, Anhui Province, the multi-environmental substitute indexes such as the grain-size, Rb/Sr, zircon crystal morphology and magnetic susceptibility were analyzed. The age of archaeological strata was determined by AMS^14C dating. According to the results, combined with the information of the ancient human activities and the cultural heritage data obtained from the Longshan cultural archaeological strata, it can be concluded that （1） Before 4500 aBP, the climate was humid and water level was high in the Huaihe River and its tributaries, the drainage basin and its surrounding areas were even flooded, so the site area was submerged and there were no human activities around the site. （2） About 4500 aBP, the climate began to become drier and water level of the Huaihe River and its tributaries began to decline, thus floodplain gradually appeared, Yuhuicun Site and Longshan Culture began to appear. （3） Around 4100 aBP, the climate was humid and rainfall was abundant, which resulted in frequent flood disasters in the whole Huaihe River Basin. （4） After 4100 aBP, the climate gradually transited to be cold and dry, agricultural production was constrained to reduce the food source, Yuhuicun Site was almost abandoned. （5） The environmental information in sedimentary strata and historical records based on ancient books agree with each other. In addition, Yuhuicun Site was related to Dayu Zhishui （Yu the Great in taming the floods） in ancient books.

A diagnostic experiment of the influence of CO_2on winter wheat

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A Comparative Study of Acute Hemodynamic Effects of Multi -site Cardiac Pacing in patients with cardiac function NYHA class ⅠtoⅡ without bundle branch block

Objective To compare the acute hemodynamic effects of five different pacing modes in patients with cardiac function NYHA class Ⅰ to Ⅱ without bundle branch block (BBB). Methods This study included 12 patients (SSS 7, Ⅲ°AVB 5) undergoing pacemaker implantation. Right ventricular apex (RVA), right ventricular outflow tract (RVOT), right ventricular bifocal (RV-Bi), left ventricular base (LVB) and bi -ventricular (Bi-Ⅴ) pacing at 60 -80 ppm were done in VVI mode prior to implantation of DDD pacemaker. The cardiac index (CI), mean pulmonary artery pressure (mPAP) and pulmonary capillary wedge pressure (PCWP) were measured with Swan - Ganz thermodilution catheter after 5 minutes of each pacing mode. Results (1) Comparing to pacing at RVA (CI: 2. 41± 0. 38 L/min per m2, PCWP: 16. 7 ±3.3 mmHg), the CI increased and the PCWP decreased significantly in pacing at RVOT(CI: 2. 63 ± 0.46, PCWP: 13. 8±2. 3), LVB(CI: 2. 78±0.52, PCWP: 14. 4±3.1), RV-Bi(CI: 2. 83±0.57, PCWP: 12. 8± 2. 5) and Bi -Ⅴ pacing (CI: 2. 94± 0.60, PCWP: 12. 7±2. 5), P < 0. 01, respectively. (2) The CI of RV-Bi and Bi-Ⅴ pacing was higher than that of RVOT and LVB pacing, the PCWP was lower, P < 0. 05, respectively. (3) There was no significant difference between RV - Bi pacing and Bi-Ⅴ pacing in CI and PCWP. Conclusion There is no significant difference between RV - Bi pacing and Bi -V pacing in the acute hemodynamic effects; however,dual - site pacing is much better than single site pacing in that aspect for patients with cardiac function NYHA class Ⅰ to Ⅱ without BBB. Among single site pacing, the RVOT and LVB pacing is better than RVA pacing in cardiac function.

Language-Segmented Study Based on TripAdvisor Reviews Related to Memorable Tourist Experiences

The Memorable Tourist Experience(MTE)is a scientific concept within the studies on tourism that is developed based on several related constructions:Perceived Confidence,Sincerity,Authenticity,and Satisfaction.This work takes this model established by the work of Dr.Babak Taheri in 2018 on Monuments World Heritage of UNESCO,adopting an alternative data collection method to the face-to-face survey.Therefore,this work takes as a source of data the reviews collected in the recommendation platform TripAdvisor,working the same constructions of the MTE,with the collection of similar terms and the relationships between them.In order to highlight the terms,a first step is established with the use of Natural Language Processing(NLP),followed by the use of Machine Learning(ML)techniques to generate the relationships between the constructors defined in the models.The study makes a comparison using the method,in immaterial nature such as a flamenco show in the city of Seville;Flamenco has been declared by UNESCO an intangible World Heritage Site since 2010.The results of the study go in two directions:on the one hand to find similarities in the study of the specific MTE of both monuments with the hypotheses worked in the original model of Taheri.In addition to highlighting possible distinctive elements of each case and,and furthermore within the value contribution of the visit when it is led by an official tour guide,on the other hand,give presence to the model of obtaining data by reviews as a complementary data source of any tourist study.The data collection and analysis from both NLP and ML techniques permit the scientific study and the tourist operators to develop better value propositions to users and understanding of heterogeneous behaviors in the tourism industry.The study of reviews within the MTE allows identifying the stimulus that leads the user to choose an activity and hire it.These studies are extendable to other industries and business models,given the importance that references acquire within the consumer willing to buy.For the scientific community,the use of ML is a solid way to initiate studies on behavioral models,supplement them,and accept or reject hypotheses.When the source of the data is taken from free expressions,such as reviews,the appearance of bias in the behavior is attenuated.

“在场”到“难忘”:偏惯常环境下旅游体验的记忆形成与反馈机制

体验经济时代,提供难忘的旅游体验成为目的地的核心竞争力,旅游体验作为旅游研究的重要领域得到广泛重视。然而,现有研究在空间上强调非惯常环境下的旅游体验,时间上侧重在场体验,对偏惯常环境下的难忘体验缺乏关注。因此,该研究以游客在城市绿道这一偏惯常环境下的旅游休闲活动为情境,通过在场和归家后的历时分析,旨在洞悉从“在场”到“难忘”这一体验记忆的形成过程与反馈机制。通过对5个城市绿道中的55名受访者进行两阶段考察,采用主题分析和系统动力分析,研究发现,游客在场体验以“存在性自我”为核心,且随时间推移其在场体验细节会消减,而彼时感知和感觉到的体验则抽象为情感性欣赏、满足和认同长期保存,成为记忆中的难忘体验。同时,研究提出了“在场感知-阈限自我-情感记忆-情感连接-行为动机”的体验记忆形成和促进重游的正反馈机制,与重游下体验阈限突破的负反馈机制构成体验记忆形成的S形曲线模型,对旅游体验、体验记忆以及目的地体验设计具有一定的理论和实践意义。

RAD51基因突变的首诊卵巢癌患者真实患病体验质性研究

目的:了解DNA重组修复基因(RAD51)突变的首诊卵巢癌(OC)患者真实患病体验,为后续制定干预措施提供理论依据.方法:采用目的抽样的方法抽取2022年1-12月在北京市某三级甲等医院妇科收治的RAD51基因突变、未开展治疗的OC患者作为研究对象,采用现象学方法进行半结构化访谈并现场录音,应用Colaizzi现象学7步分析法对访谈资料进行分析、提炼主题.结果:本研究归纳提炼出3个主题,即积极与消极并存、希望专业指导和行为观念转变.RAD51基因突变OC患者存在明显的负性情绪,也有积极心态养成的趋势,存在自我行为观念转变,有意愿监督易感亲属行为,对OC的认知程度较低,希望得到专业指导.结论:RAD51基因突变OC患者存在负性情绪及认知不足的情况,医护人员应及时关注RAD51基因突变OC患者的负性情绪,促进其积极心态的养成,纠正患者的不良认知.医疗机构应尽早构建OC基因检测咨询体系,为患者提供专业基因检测后续指导.

燃料包壳表面沉积层对汽化核心密度影响的实验研究

燃料包壳表面沉积层在压水堆常规运行中形成,其对包壳沸腾传热的影响尚不清楚。为了探索包壳表面沉积层对汽化核心密度的影响规律,本文基于常压下的流动沸腾可视化实验台架,以锆-4合金为基板,采用逐层沉积的方法形成不同厚度的SiO_(2)沉积层,通过开展流动沸腾实验对比不同沉积层厚度下的汽化核心密度差异。研究发现,SiO_(2)沉积表面与未沉积表面相比汽化核心密度增大,Koncar模型可较好地预测本实验工况条件下的汽化核心密度。

致密砾岩水力裂缝扩展大型矿场实验

砾岩储层由于砾石的存在而具有极强的非均质性,砾岩压裂成缝机理复杂.受限于岩样尺寸和实验条件,室内压裂物理模拟受砾石尺寸效应影响显著,裂缝扩展时间尺度小.为真实记录裂缝动态扩展过程,反映现场实际工况条件下的压后裂缝宏观整体形态,搭建一套超大尺寸(2.0 m×2.0 m×1.0 m)真三轴水力压裂矿场实验平台,通过万吨级应力加载装置、真实管汇和压裂泵车,实现现场真实工况条件下的砾岩水力压裂模拟.基于该平台,分析了水平应力差、压裂液黏度和单孔进液速率对砾岩压裂裂缝动态扩展过程和压后裂缝宏观整体形态的影响规律.实验结果表明,砾岩压裂趋于在井筒处形成“纵向缝+横切缝”的复杂多裂缝形态,远离井筒后,横切主缝扩展优势逐步显现,局部遇砾形成分支缝;12 MPa高水平应力差条件下,压后近井区域形成多缝竞争扩展的复杂裂缝带,横切主缝向远端延伸优势减弱;压裂液黏度低于50 mPa·s时,压后横切主缝扩展优势显著,当压裂液黏度高于50 mPa·s时,近井区域形成复杂多裂缝形态;单孔进液速率超过0.3 m^(3)/min后,井筒处趋于形成多条纵向缝,易导致段间压窜.研究成果有助于深化认识砾岩储层压裂裂缝真实形态,为砾岩水力压裂方案设计提供理论指导.

拥挤会唤醒游客负面情绪吗?基于泰山观日情境的实证研究

拥挤是遗产地旅游管理中比较常见的问题之一,但现有研究对拥挤是否导致游客负面情绪并影响游客满意度和忠诚度的问题存在分歧。本文以登顶泰山看日出的游客为研究样本,基于“刺激—机体—反应”理论,通过问卷数据的结构方程模型与Boot st r ap中介效应检验,实证检验了拥挤与游客情绪、满意度、忠诚度的关系。结果表明:(1)游客拥挤感知包括物理空间、个人空间、社交空间拥挤感知三个维度,且三者之间存在依次递进的关系;(2)三种拥挤感知对游客负面情绪的影响具有相应递进性,当物理空间拥挤、个人空间拥挤上升到社交空间拥挤时,拥挤限制体验产生的负面情绪超越旅游情境带来的正面情绪,游客的负面情绪被唤醒;(3)拥挤通过游客情绪间接影响游客满意度和忠诚度,即只有当拥挤导致游客负面情绪时才会负向影响游客满意度和忠诚度。本文揭示了拥挤与游客负面情绪、满意度、忠诚度的关系,对游客情绪管理与容量管理的理论与实践具有现实意义。

深海科学实验装备发展研究

深海孕育了世界上最大的生态系统,对深海相关演变规律的深刻认知将支撑人类社会的可持续发展;深海极端环境条件决定了开展原位实验作业非常困难,也对深海科学实验装备提出了苛刻的要求。本文从深海科学实验研究的视角出发,按照深海试验装备及试验场、深海原位探测与实验装备、深海环境模拟实验装备的主要划分,系统梳理了国内外深海科学实验装备的发展态势和面临的问题。我国在深海科学实验装备领域已形成了一批自主研发的装备技术,推动了深海科学研究进步,部分优势方向已跻身国际先进水平;但在高精尖装备及其关键核心技术方面未能构建成熟的产业链,导致部分装备发展受限、一些技术薄弱环节凸显。需要加强顶层谋划、协调技术攻关,建立激励机制、推动创新转化,建设示范平台、形成标准体系,突破传感技术、加快国产进程,加强国际合作、提升创新能力,以深海科学实验装备高质量发展推动深海科学研究和海洋强国建设。

可液化场地桩-土结构相互作用研究综述

近年来,可液化场地桩-土-桥梁结构互作用问题一直是理论研究的热点。首先回顾了国内外破坏性地震中由于场地液化造成的桩基震害现象及其损伤破坏机理;然后梳理了国内外学者在液化场地桩-土相互作用领域开展的数值模拟、实验研究,系统总结了两种典型数值模拟方法、三类实验研究方法,并对其优劣进行了初步分析;最后,分析了现有研究存在的不足,提出了亟待解决的相关问题,给出了研究建议。研究成果可为该领域研究人员提供基础性借鉴。

数字赋能下文旅产品消费者在场体验影响因素与互动机理——基于意识谱理论的扎根研究

研究数字文旅产品消费者体验,有助于丰富旅游体验理论,有利于数字技术赋能下展览产品健康发展。通过对六个案例消费点评与访谈数据等的质性分析,基于意识谱理论,发掘数字赋能下消费者在场体验的形成因素与互动机制。研究发现:个人情境、在场氛围感知、在场知性认知、在场感性认知是影响消费者在场体验的四大主范畴。在个体心境、涉入能力、物理空间氛围、服务氛围、非物理空间氛围、交互感知等11个副范畴中,虚拟场景体验时消费者受呈现感知、知识提取、知识编码、交互感知、衍生设计、便利因素的影响;实体场景体验时消费者受非物理空间氛围、物理空间氛围、服务氛围因素的影响;两种场景中消费者同时受涉入能力、个体心境因素的影响。在此基础上,构建消费者在场体验的机理过程模型,以解读数字文旅产品如何引起消费者在场行为变化,进而导致在场情感体验发生,希冀为数字赋能下文旅产品设计提供决策依据。

河北省深层地下水回补研究

为改善河北省地下水严重亏空、地下水降落漏斗长期存在的局面,缓解地下水超采引发的一系列生态环境问题,近年来河北省大力推进地下水超采综合治理。深层地下水回补是减缓地面沉降、控制地下水水位降落漏斗、解决海(咸)水入侵问题的重要措施之一。介绍了国内外地下水回补的典型案例和回补方式方法,从机理、技术、经济三方面分析了深层地下水人工回补的主要难点,重点阐述了河北省深层地下水回补试点进展及试验场布设方案,结合河北省实际提出深层地下水回补工作建议,以期为系统开展深层地下水修复、提升地下水战略储备能力、促进地下水可持续利用提供有益参考。

工地扬尘管控措施效果量化研究

随着城市规划建设,大规模建筑工程在地基开挖、主体建设、外墙装修过程中,会产生以粗颗粒物(PM_(10))为代表的众多大气污染物。为尽量减少建筑工地扬尘产生PM_(10),相关部门要求建筑工地采取裸土覆盖、立体喷淋、围挡隔离等抑尘措施。基于现场抑尘措施控制试验和高精度数值风洞试验对各措施的抑尘效果进行逐一探究。结果表明:只开围挡喷淋时PM_(10)浓度下降5.1%,只开施工喷淋时浓度下降12.3%,二者全开时浓度下降11.4%。风速较大时,裸土覆盖的抑尘效果比小风天气显著,在三级风(大于2 m/s)下裸土覆盖的PM_(10)浓度均值相比裸土不覆盖时平均下降10.7%。裸土喷淋后的PM_(10)浓度比不喷淋时下降21.3%。整体上基坑阶段在围挡2、3、4和5 m时的扬尘削减率分别为3.6%、10.5%、18.4%和29.0%。在主体阶段,随着排放源的升高,扬尘扩散的影响距离逐渐降低。当源高10 m时,最大影响距离为工地外75 m;当源高30 m时,最大影响距离为工地外50 m;当源高50和90 m时,刚出工地的扬尘逸散率便在10%以内,即对工地外的影响可以忽略。

遗产地的无障碍环境设计与建设--基于亚洲经验的比较

文章寻求在遗产地规划和无障碍环境设计两方面的研究及实施之间建立起重要的关联,对目前已经开展的关于城市无障碍环境的探讨,在空间范畴和社会内涵上进行了拓展与延伸。文章首先对"遗产地"和"无障碍环境"的概念及内涵进行阐释,随后剖析当前遗产地无障碍环境设计与建设现状中的问题及成因,并强调遗产地无障碍环境设计与建设的重要性;在上述分析基础上,将日本、印度、孟加拉国和中国遗产地的无障碍环境案例作了比较,分析亚洲部分国家无障碍环境设计的相关法律、法规和标准;最后提出了对中国遗产地无障碍环境设计与建设的启示。