Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer ...Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer unit is usually equipped. However, the pump motor energy transfer has the characteristics of poor starting and low response, which cause long time of pressure adjustment and large pressure jitter when the transformer is switched to system suddenly and the motor-side pressure has pressure impact when rail of the pump-side is switched. To address these problems, this paper proposes a compound control strategy of feedforward compensation control with Fuzzy-PID to improve the controllability of the multi-level pressure source system. A test rig of the pump motor energy transfer unit is built and the controllability of compound controller and PID controller are compared. The experiment results show that, compared with the traditional PID, the adjustment time and the pressure impact are reduced by 20% and 25% with the proposed compound control strategy. Therefore, the presented compound control strategy can be used to improve starting performance and robustness of the pump motor energy transfer unit control system.展开更多
Based on single drop mass transfer models and two phase flow equation,a general equationfor calculating the‘true’height of transfer unit of extraction columns was derived and tested withfour types of extraction colu...Based on single drop mass transfer models and two phase flow equation,a general equationfor calculating the‘true’height of transfer unit of extraction columns was derived and tested withfour types of extraction columns with some different working systems.The calculated results fittedwell with those obtained by experiments.展开更多
The FCC unit with addition of various inventories of the FP-DSN type sulfur transfer additive was tested in a commercial scale. The effect of the sulfur transfer additive was analyzed by investigating the indicators r...The FCC unit with addition of various inventories of the FP-DSN type sulfur transfer additive was tested in a commercial scale. The effect of the sulfur transfer additive was analyzed by investigating the indicators related with the regenerator flue gas composition,the dry gas composition before desulfurization,the LPG composition before desulfurization,the acid gas,and the yield of gasoline and diesel. The test results indicated that the sulfur was trans ferred from the feed stream into the dry gas,LPG and acid gas,and the sulfur transfer effect was obvious only when the inventory of sulfur transfer additive exceeded over 2.0% of total FCC catalyst inventory.展开更多
The ONIOM quantum mechanics method is used to study the reaction of one-carbon unit transfer from an imidazolidine to 6- aminouracil model with the participation of water molecules.The computation results show that in...The ONIOM quantum mechanics method is used to study the reaction of one-carbon unit transfer from an imidazolidine to 6- aminouracil model with the participation of water molecules.The computation results show that in this reaction the participation of H_2O molecule makes the energy barrier lower because of the H-bond interaction.展开更多
ONIOM quantum mechanics method is used in this paper to study one-carbon unit transfer from imidazolidine to 6-aminouracil derivates. The computation results show that this reaction can be completed via three paths ow...ONIOM quantum mechanics method is used in this paper to study one-carbon unit transfer from imidazolidine to 6-aminouracil derivates. The computation results show that this reaction can be completed via three paths owing to the three different proton transfer modes. By calculation and analysis, we can find the direct proton transfer is the preferable pathway.展开更多
Density Functional Theory (DFT) method was used in this paper to study one-carbon transfer from 1,10-tetrahydroquinoxaline, an analogue of tetrahydrofolic acid, to methylamine. This reaction can be completed via two ...Density Functional Theory (DFT) method was used in this paper to study one-carbon transfer from 1,10-tetrahydroquinoxaline, an analogue of tetrahydrofolic acid, to methylamine. This reaction can be completed via two paths. From the computation result we can conclude that a general-acid catalysis exists in this reaction. By computation we find DFT has its limitation in describing a newly incorporated structure with a unit charge.展开更多
<strong>Introduction:</strong> Patient’s transfer from the intensive care unit (ICU) to the general ward indicates their improving health status. However, the transfer produces anxiety when patients enter...<strong>Introduction:</strong> Patient’s transfer from the intensive care unit (ICU) to the general ward indicates their improving health status. However, the transfer produces anxiety when patients enter an unfamiliar environment with different care protocols and circumstances. <strong>Objectives:</strong> This study aimed to examine the level of ICU transfer anxiety among open heart surgery patients and determine the psychosocial factors associated with ICU transfer anxiety among open heart surgery patients. <strong>Methods:</strong> Data were collected in a cardiac center in Kathmandu City, Nepal among 95 open heart surgery patients within 24 hours of their transfer from an ICU to a general ward. The study used four self-reported questionnaires, namely the modified Mishel Uncertainty in Illness Scale for Adults, modified Brief COPE Inventory, Nurses’ Support Questionnaire, and State Anxiety Inventory. <strong>Results:</strong> Fifty-two patients (54.7%) had a high level of transfer anxiety. Spearman’s rank correlation showed that uncertainty in illness, coping, and nurses’ support were significantly related to transfer anxiety (<em>p</em> < 0.001). <strong>Conclusion:</strong> The results of this study suggest nurses to address uncertainty in illness of the patients, improve their coping abilities, and provide need-based nursing support to them during the transitional phase. Besides, clinicians and governmental agencies should contribute to implication of transitional guidelines, which can reduce transfer anxiety and promote health and recovery of the patients.展开更多
目的系统分析中国重症监护室(intensive care unit,ICU)转出患者家属迁移应激的影响因素,为减轻转出患者家属迁移应激水平提供循证依据。方法计算机检索中国知网、万方数据知识服务平台、维普、中国生物医学文献数据库、Web of Science...目的系统分析中国重症监护室(intensive care unit,ICU)转出患者家属迁移应激的影响因素,为减轻转出患者家属迁移应激水平提供循证依据。方法计算机检索中国知网、万方数据知识服务平台、维普、中国生物医学文献数据库、Web of Science、PubMed、the Cochrane Library、Embase中有关ICU转出患者家属迁移应激影响因素的队列研究、病例对照研究、横断面研究等观察性研究,检索时限为建库至2023年10月。由2名研究者按照纳入及排除标准单独进行文献筛选、质量评价和资料提取。采用RevMan5.4软件对数据结果进行Meta分析。结果最终纳入15篇研究,总样本量2558,共提取12个影响因素。将15篇文献根据测量结局指标的工具分为正向计分组(得分越高,迁移应激水平越高,共9篇文献)、反向计分组(得分越高,迁移应激水平越低,共6篇文献)。分析每个组别时,仅对组内提及≥2次的影响因素进行Meta分析。Meta分析结果显示:正向计分组内,家属文化程度、家属性别、患者意识、ICU治疗时间、家属疾病不确定感是ICU转出患者家属迁移应激的影响因素(P<0.05);反向计分组内,家属文化程度、家属性别、患者年龄、ICU治疗时间是ICU转出患者家属迁移应激的影响因素(P<0.05)。敏感度分析结果显示各个因素的结果均较为稳定。结论家属文化程度、家属性别、患者年龄、ICU治疗时间、家属疾病不确定感是中国ICU转出患者家属迁移应激的影响因素,家属宗教信仰、患者意识对其影响还需进一步论证。展开更多
新能源汽车的充电基础设施是新能源汽车产业的重要组成部分,是新能源汽车最重要的配套基础设施。针对现有充电桩无法进行远程管理控制和数据采集的问题,基于现有充电桩和国家标准设计一款电动汽车有序充电智能管控装置。该装置主要由数...新能源汽车的充电基础设施是新能源汽车产业的重要组成部分,是新能源汽车最重要的配套基础设施。针对现有充电桩无法进行远程管理控制和数据采集的问题,基于现有充电桩和国家标准设计一款电动汽车有序充电智能管控装置。该装置主要由数据转换单元(Data Transfer Unit,DTU)和充电管理控制器组成。DTU与每台充电中的充电管理控制器及小区基础负荷总电度量表进行通信,同时通过以太网接口与服务器进行通信,实现数据的远程传输与中转。同时解决充电桩与服务器之间的连接问题。充电管理控制器作为核心部件,具备控制充电桩的通断和采集充电状态信息的功能。通过接收来自服务器的指令,可以实现对充电桩的远程控制。同时充电管理控制器还可以实时采集充电桩的充电状态信息,并将这些信息传输给服务器,以便用户和管理员进行查看和监控。展开更多
针对冷水机组的采集监控需求,设计了一套基于物联网的冷水机组数据采集监控系统。该系统通过专用物联网传输模块DTU(Data Transfer Unit)完成对冷水机组数据的实时采集和控制。采集到的冷水机组数据通过物联网数据传输单元DTU移动通信网...针对冷水机组的采集监控需求,设计了一套基于物联网的冷水机组数据采集监控系统。该系统通过专用物联网传输模块DTU(Data Transfer Unit)完成对冷水机组数据的实时采集和控制。采集到的冷水机组数据通过物联网数据传输单元DTU移动通信网,远程上传到云端控制中心,控制中心的软件实现了对冷水机组的数据采集监测和远程控制指令的下发。该系统实现了冷水机组的远程监测和控制,降低了系统运营成本,提高了系统工作效率和自动化水平。展开更多
文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Da...文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Data Transfer Unit,DTU)模块的实时监测系统。系统通过现场控制终端采集通信电源设备的运行状态信息,经模拟数字(Analog to Digital,AD)转换模块处理后,由ARM核心控制芯片发送至无线模块,最终传输至远程监控中心。此外,设计一套应急预案,包括应急预案设计原则、组织机构与职责、应急分级、启动条件与工作流程以及保障措施等,以应对电网大停电带来的经济损失。通过技术保障、装备保障、人员保障,实现抢修工作的快速响应,缩短断电时间,有效减少经济损失,确保生产生活不受影响。展开更多
基金Supported by the National Natural Science Foundation of China(No.51575471)the Key Project of Science and Technology Plan of Higher Education of Hebei Education Department(No.ZD2017077)
文摘Multi-level pressure source system is a novel hydraulic system with distinct advantage of energy saving. In order to balance each pressure level of the multi-level pressure source system, a pump motor energy transfer unit is usually equipped. However, the pump motor energy transfer has the characteristics of poor starting and low response, which cause long time of pressure adjustment and large pressure jitter when the transformer is switched to system suddenly and the motor-side pressure has pressure impact when rail of the pump-side is switched. To address these problems, this paper proposes a compound control strategy of feedforward compensation control with Fuzzy-PID to improve the controllability of the multi-level pressure source system. A test rig of the pump motor energy transfer unit is built and the controllability of compound controller and PID controller are compared. The experiment results show that, compared with the traditional PID, the adjustment time and the pressure impact are reduced by 20% and 25% with the proposed compound control strategy. Therefore, the presented compound control strategy can be used to improve starting performance and robustness of the pump motor energy transfer unit control system.
基金Supported by the National Natural Science Foundation of China.
文摘Based on single drop mass transfer models and two phase flow equation,a general equationfor calculating the‘true’height of transfer unit of extraction columns was derived and tested withfour types of extraction columns with some different working systems.The calculated results fittedwell with those obtained by experiments.
文摘The FCC unit with addition of various inventories of the FP-DSN type sulfur transfer additive was tested in a commercial scale. The effect of the sulfur transfer additive was analyzed by investigating the indicators related with the regenerator flue gas composition,the dry gas composition before desulfurization,the LPG composition before desulfurization,the acid gas,and the yield of gasoline and diesel. The test results indicated that the sulfur was trans ferred from the feed stream into the dry gas,LPG and acid gas,and the sulfur transfer effect was obvious only when the inventory of sulfur transfer additive exceeded over 2.0% of total FCC catalyst inventory.
文摘The ONIOM quantum mechanics method is used to study the reaction of one-carbon unit transfer from an imidazolidine to 6- aminouracil model with the participation of water molecules.The computation results show that in this reaction the participation of H_2O molecule makes the energy barrier lower because of the H-bond interaction.
文摘ONIOM quantum mechanics method is used in this paper to study one-carbon unit transfer from imidazolidine to 6-aminouracil derivates. The computation results show that this reaction can be completed via three paths owing to the three different proton transfer modes. By calculation and analysis, we can find the direct proton transfer is the preferable pathway.
基金This work was supported by the grant from the National Natural Science Foundation of China (No. 29973021)
文摘Density Functional Theory (DFT) method was used in this paper to study one-carbon transfer from 1,10-tetrahydroquinoxaline, an analogue of tetrahydrofolic acid, to methylamine. This reaction can be completed via two paths. From the computation result we can conclude that a general-acid catalysis exists in this reaction. By computation we find DFT has its limitation in describing a newly incorporated structure with a unit charge.
文摘<strong>Introduction:</strong> Patient’s transfer from the intensive care unit (ICU) to the general ward indicates their improving health status. However, the transfer produces anxiety when patients enter an unfamiliar environment with different care protocols and circumstances. <strong>Objectives:</strong> This study aimed to examine the level of ICU transfer anxiety among open heart surgery patients and determine the psychosocial factors associated with ICU transfer anxiety among open heart surgery patients. <strong>Methods:</strong> Data were collected in a cardiac center in Kathmandu City, Nepal among 95 open heart surgery patients within 24 hours of their transfer from an ICU to a general ward. The study used four self-reported questionnaires, namely the modified Mishel Uncertainty in Illness Scale for Adults, modified Brief COPE Inventory, Nurses’ Support Questionnaire, and State Anxiety Inventory. <strong>Results:</strong> Fifty-two patients (54.7%) had a high level of transfer anxiety. Spearman’s rank correlation showed that uncertainty in illness, coping, and nurses’ support were significantly related to transfer anxiety (<em>p</em> < 0.001). <strong>Conclusion:</strong> The results of this study suggest nurses to address uncertainty in illness of the patients, improve their coping abilities, and provide need-based nursing support to them during the transitional phase. Besides, clinicians and governmental agencies should contribute to implication of transitional guidelines, which can reduce transfer anxiety and promote health and recovery of the patients.
文摘目的系统分析中国重症监护室(intensive care unit,ICU)转出患者家属迁移应激的影响因素,为减轻转出患者家属迁移应激水平提供循证依据。方法计算机检索中国知网、万方数据知识服务平台、维普、中国生物医学文献数据库、Web of Science、PubMed、the Cochrane Library、Embase中有关ICU转出患者家属迁移应激影响因素的队列研究、病例对照研究、横断面研究等观察性研究,检索时限为建库至2023年10月。由2名研究者按照纳入及排除标准单独进行文献筛选、质量评价和资料提取。采用RevMan5.4软件对数据结果进行Meta分析。结果最终纳入15篇研究,总样本量2558,共提取12个影响因素。将15篇文献根据测量结局指标的工具分为正向计分组(得分越高,迁移应激水平越高,共9篇文献)、反向计分组(得分越高,迁移应激水平越低,共6篇文献)。分析每个组别时,仅对组内提及≥2次的影响因素进行Meta分析。Meta分析结果显示:正向计分组内,家属文化程度、家属性别、患者意识、ICU治疗时间、家属疾病不确定感是ICU转出患者家属迁移应激的影响因素(P<0.05);反向计分组内,家属文化程度、家属性别、患者年龄、ICU治疗时间是ICU转出患者家属迁移应激的影响因素(P<0.05)。敏感度分析结果显示各个因素的结果均较为稳定。结论家属文化程度、家属性别、患者年龄、ICU治疗时间、家属疾病不确定感是中国ICU转出患者家属迁移应激的影响因素,家属宗教信仰、患者意识对其影响还需进一步论证。
文摘新能源汽车的充电基础设施是新能源汽车产业的重要组成部分,是新能源汽车最重要的配套基础设施。针对现有充电桩无法进行远程管理控制和数据采集的问题,基于现有充电桩和国家标准设计一款电动汽车有序充电智能管控装置。该装置主要由数据转换单元(Data Transfer Unit,DTU)和充电管理控制器组成。DTU与每台充电中的充电管理控制器及小区基础负荷总电度量表进行通信,同时通过以太网接口与服务器进行通信,实现数据的远程传输与中转。同时解决充电桩与服务器之间的连接问题。充电管理控制器作为核心部件,具备控制充电桩的通断和采集充电状态信息的功能。通过接收来自服务器的指令,可以实现对充电桩的远程控制。同时充电管理控制器还可以实时采集充电桩的充电状态信息,并将这些信息传输给服务器,以便用户和管理员进行查看和监控。
文摘针对冷水机组的采集监控需求,设计了一套基于物联网的冷水机组数据采集监控系统。该系统通过专用物联网传输模块DTU(Data Transfer Unit)完成对冷水机组数据的实时采集和控制。采集到的冷水机组数据通过物联网数据传输单元DTU移动通信网,远程上传到云端控制中心,控制中心的软件实现了对冷水机组的数据采集监测和远程控制指令的下发。该系统实现了冷水机组的远程监测和控制,降低了系统运营成本,提高了系统工作效率和自动化水平。
文摘文章针对通信电源系统易受多种因素影响的特点,开发了一种基于高级精简指令集计算机机器(Advanced Reduced Instruction Set Computer Machines,ARM)核心控制芯片和通用分组无线业务(General Packet Radio Service,GPRS)数据传输单元(Data Transfer Unit,DTU)模块的实时监测系统。系统通过现场控制终端采集通信电源设备的运行状态信息,经模拟数字(Analog to Digital,AD)转换模块处理后,由ARM核心控制芯片发送至无线模块,最终传输至远程监控中心。此外,设计一套应急预案,包括应急预案设计原则、组织机构与职责、应急分级、启动条件与工作流程以及保障措施等,以应对电网大停电带来的经济损失。通过技术保障、装备保障、人员保障,实现抢修工作的快速响应,缩短断电时间,有效减少经济损失,确保生产生活不受影响。
