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Computer Modeling in Engineering & Sciences 2023年第2期134卷 1177-1194页

作者： bida zhang Qiang Yan Hairui zhang Lin zhang Beijing University of Posts and Telecommunications Beijing100876China PLA Army Academy of Artillery and Air Defense Zhengzhou450000China Beijing Information Science and Technology University Beijing100192China

The joint location planning of charging/battery-swap facilities for electric vehicles is a complex *** the differences between these two modes of power replenishment,we constructed a joint location-planning model to minimize construction and operation costs,user costs,and user satisfaction-related penalty *** designed an improved genetic algorithm that changes the crossover rate using the fitness value,memorizes,and transfers excellent *** addition,the present model addresses the problem of“premature convergence”in conventional genetic algorithms.A simulated example revealed that our proposed model could provide a basis for optimized location planning of charging/battery-swapping facilities at different levels under different charging modes with an improved computing *** example also proved that meeting more demand for power supply of electric vehicles does not necessarily mean increasing the sites of charging/battery-swap ***,optimizing the level and location planning of charging/battery-swap stations can maximize the investment *** proposed model can provide a reference for the government and enterprises to better plan the location of charging/battery-swap ***,it is of both theoretical and practical value.

关键词： Charging/battery-swapping facility genetic algorithm location planning excellent gene cluster

抗生素对共培养的萱藻丝状体和膨胀色球藻生长的影响

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水产学报 2014年第9期38卷 1466-1475页

作者：马旺楠宫相忠张文健高伟张必达中国海洋大学海洋生命学院长岛爱华海藻食品有限公司

为抑制萱藻丝状体扩增过程中出现的膨胀色球藻的生长,采用实验生态学方法,研究了链霉素、氨苄青霉素、卡那霉素、庆大霉素和氯霉素等5种常用抗生素对共培养条件下的萱藻丝状体和膨胀色球藻生长的影响。结果显示,(1)链霉素浓度为100μg/m... 详细信息

为抑制萱藻丝状体扩增过程中出现的膨胀色球藻的生长,采用实验生态学方法,研究了链霉素、氨苄青霉素、卡那霉素、庆大霉素和氯霉素等5种常用抗生素对共培养条件下的萱藻丝状体和膨胀色球藻生长的影响。结果显示,(1)链霉素浓度为100μg/mL时可以显著抑制膨胀色球藻生长,而不影响萱藻丝状体的生长;(2)氨苄青霉素和庆大霉素对膨胀色球藻产生明显抑制作用的浓度均为100μg/mL,对萱藻丝状体产生抑制作用的浓度分别为100和500μg/mL;(3)10μg/mL卡那霉素可强烈抑制膨胀色球藻生长,而萱藻丝状体没有出现被抑制的现象;(4)氯霉素对膨胀色球藻和萱藻丝状体均有较强的抑制作用,10μg/mL可以对膨胀色球藻的生长产生显著抑制,浓度达到50μg/mL后,萱藻丝状体生长受到抑制。研究表明,链霉素(100μg/mL)、卡那霉素(100μg/mL)和氯霉素(10μg/mL)可以用于降低萱藻种质保存和扩增过程中萱藻丝状体被膨胀色球藻污染的风险。

关键词：萱藻膨胀色球藻丝状体抗生素共培养

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五种培养液对萱藻丝状体生长发育的影响

水产学报 2015年第2期39卷 193-202页

作者：洪丽珍宫相忠张文健高伟张必达中国海洋大学海洋生命学院长岛爱华海藻食品有限公司

以实验室保存的萱藻丝状体为材料,采用实验生态学方法,探讨了L1、PES、F1、f/2以及ESNW 5种培养液对萱藻丝状体生长发育的影响,并以去除氮或磷成分的L1培养液为基础,研究了不同外加浓度氮和磷对萱藻丝状体生长发育的影响。结果显示:(1)... 详细信息

以实验室保存的萱藻丝状体为材料,采用实验生态学方法,探讨了L1、PES、F1、f/2以及ESNW 5种培养液对萱藻丝状体生长发育的影响,并以去除氮或磷成分的L1培养液为基础,研究了不同外加浓度氮和磷对萱藻丝状体生长发育的影响。结果显示:(1)5种培养液中,L1培养液最有利于萱藻丝状体的生长发育,经L1培养液培养的萱藻丝状体呈深褐色,细胞质充盈,培养28 d后,丝状体生物量增重倍比可达(560.48%±0.73%),孢子囊枝比例高达(46.88%±0.41%),孢子囊直径为(18.95±0.89)μm;(2)萱藻丝状体生长发育最适添加NO-3-N浓度为6.00 mg/L,在此NO-3-N浓度条件下,萱藻丝状体生长速度最快,丝状体呈深褐色,培养20 d后,孢子囊枝比例高达(46.78%±0.14%),孢子囊直径可达(18.78±2.45)μm。在添加NO-3-N浓度为0 mg/L和高氮(96.00、192.00 mg/L)条件下,萱藻丝状体生长速度均相对较慢,丝状体色素淡,培养20 d后,孢子囊枝比例分别仅为(0%±0%)、(9.06%±0.32%)和(7.65%±0.45%),孢子囊直径仅9.0010.00μm;(3)萱藻丝状体生长发育的最适外加PO3-4-P浓度为1.32 mg/L,在此PO3-4-P浓度条件下,萱藻丝状体生长速度最快且丝状体呈深褐色,培养20 d后,孢子囊枝比例高达(47.12%±0.26%),孢子囊直径可达(18.89±0.98)μm。外加PO3-4-P为0 mg/L时,萱藻丝状体色素淡,培养20 d后,孢子囊枝比例仅为(10.12%±0.27%),孢子囊直径仅有(9.78±1.32)μm。外加PO3-4-P高于15.84 mg/L时,丝状体出现"不良"生长状况——变绿、细胞解体、附着解体的丝状体碎屑且没有孢子囊枝的形成。研究证明,在萱藻丝状体的生长发育过程中,应选择一种合适的培养液以及适时地控制硝酸盐与磷酸盐的浓度,使其维持在一定范围内,从而促进萱藻丝状体的快速生长,提高其孢子囊枝比例、增大孢子囊直径。

关键词：萱藻丝状体培养液生长发育

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萱藻丝状体的种质保存技术

水产学报 2014年第7期38卷 1026-1033页

作者：庄琰宫相忠张文健高伟张必达中国海洋大学海洋生命学院长岛爱华海藻食品有限公司

采用液体保存法和胶囊化低温保存法对萱藻丝状体进行保存,探讨了液体培养法中温度、光照强度以及胶囊化低温保存法中胶球含水量对萱藻丝状体种质保存的影响。结果显示:(1)在液体保存法中,温度对萱藻丝状体的保存影响较小,当光强为5.4μm... 详细信息

采用液体保存法和胶囊化低温保存法对萱藻丝状体进行保存,探讨了液体培养法中温度、光照强度以及胶囊化低温保存法中胶球含水量对萱藻丝状体种质保存的影响。结果显示:(1)在液体保存法中,温度对萱藻丝状体的保存影响较小,当光强为5.4μmol/(m2·s)时,6~18℃均可实现萱藻丝状体的长期保存;(2)光照强度对萱藻丝状体的液体保存影响显著,16.2μmol/(m2·s)及以上的光强不利于种质的保存,5.4μmol/(m2·s)对萱藻丝状体的液体保存最有利;(3)在6~18℃,5.4μmol/(m2·s)条件下保存萱藻丝状体60 d后,萱藻丝状体细胞状态良好且存活率仍在97%以上;(4)胶球含水量过高或过低均会降低萱藻丝状体胶囊化低温保存后的存活率,15%是萱藻丝状体胶球的最适含水量,在该条件下,萱藻丝状体保存1个月后的存活率仍在50%以上。研究证明,在适宜条件下,液体保存法和胶囊化低温保存法均可实现萱藻丝状体的种质保存。

关键词：萱藻丝状体温度光照强度液体保存胶囊化低温保存

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数据挖掘助力LTE网络规划

邮电设计技术 2015年第3期 44-48页

作者：张必达王森曹凡中讯邮电咨询设计院有限公司河南郑州450007

将数据挖掘技术利用在LTE网络规划中,对存储在市场、建设、维护等部门系统中的数据进行整合与分析,建立了综合套餐分类、终端类型、用户行为、终端更新频率等信息在内的多维度评估模型挖掘LTE潜在用户,并在此基础上为运营商制定客户化... 详细信息

将数据挖掘技术利用在LTE网络规划中,对存储在市场、建设、维护等部门系统中的数据进行整合与分析,建立了综合套餐分类、终端类型、用户行为、终端更新频率等信息在内的多维度评估模型挖掘LTE潜在用户,并在此基础上为运营商制定客户化的小区级价值区域。

关键词：数据挖掘网络规划 LTE

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Theory and Method of Spatial Encoding in MR Imaging

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Theory and Method of Spatial Encoding in MR Imaging

CCAST“北京第二次医学影像物理和工程”国际研讨会

作者： zhang bida Wang Weidong Bao Shanglian Chen Guangfei(1 Institute of Heavy Ion Physics Peking University Beijing 1008712 PLA General Hospital Beijing 1008533 Research Center of Physical Technologies on Tumor Diagnosis and Therapy Peking University Beijing 100871)

＜正＞ In this study, through introducing a function of sensitivity profile of RF receiver coil, denoted b（x,y,z）, we scribed the imaging methods with a uniform formula. We commented on the traditional theory and imaging technique of MRI systematically and discussed fast MR imaging approaches with the parallel fashion: in traditional MRI theory, the sensitivity profile of RF receiver coil is designed as uniform. The data acquisition reduction is depended upon the power of the gradient field amplifier and its fast slew rate. But nowadays in conventional fast imaging schemes the gradient switching time and gradient field amplitude have become mayor obstacles to save the image time and improve SNR of signals. People considered spatial encoding in parallel scheme by means of RF coil array and its sensitivity distributions. New imaging methods, named spatial local Fourier transform and spatial wavelet Radio Frequency encoding, were proposed in this article. The realization of the two methods mentioned above may need the support of phased-array coil technique.

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基于FDD-LTE的室内覆盖解决方案探讨

邮电设计技术 2013年第10期 35-38页

作者：王森张必达席向涛中讯邮电咨询设计院有限公司河南郑州450007

在分析传统室内分布、通道变频和新型光纤分布三种LTE室内覆盖解决方案的基础上,讨论了不同解决方案的优劣性及设计思路,给出了在LTE建网初期不同场景下适用的解决方案。

关键词： LTE 室内覆盖设计思路

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Digitalization decoupling method and its application to the phased array in MRI

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Progress in Natural Science:Materials International 2003年第9期 45-51页

作者： SONG Xiaoyu, WANG Weidong, zhang bida, LEI Ming and BAO Shanglian (1. Institute of Heavy Ion Physics, the Beijing Key Laboratory of Medical Physics & Engineering, Peking University, Beijing 100871, China 2. The General Hospital of PLA, Beijing 100853, China 3. Institute of 503, Spaceflight Scientific Group Company, Beijing 100086, China) Institute of Heavy Ion Physics，the Beijing Key Laboratory of Medical Physics & Engineering，Peking University，Beijing 100871，China Institute of Heavy Ion Physics，the Beijing Key Laboratory of Medical Physics & Engineering，Peking University，Beijing 100871，China The General Hospital of PLA，Beijing 100853，China Institute of 503，Spaceflight Scientific Group Company，Beijing 100086，China

A general network decoupling method for phased array radio frequency coil used in magnetic resonance imaging is devel-oped. A more flexible digital approach further simplifies the method, which has an even higher signal-to-noise ratio. The performance ofthe digitalized decoupling method was confirmed by the calculated result by using a high frequency structure simulation software with themethod of finite element for a tree-port phased array RF coil. The consistence was well established between the theoretical and simulatedresults.

关键词： MRI phased array coil decoupling digitalization.

Parallel imaging methods for phased array MRI

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Progress in Natural Science:Materials International 2003年第4期 69-72页

作者： zhang bida, WANG Weidong, SONG Xiaoyu, ZU Donglin, CHEN Guangfei and BAO Shanglian (1. Institute of Heavy Ion Physics, the Research Center for Tumor Diagnosis and Therapeutical Physics, the Beijing Key Laboratory of Medical Physics & Engineering, Peking University, Beijing 100871, China 2. General Hospital of PLA, Beijing 100085, China) Institute of Heavy Ion Physics，the Research Center for Tumor Diagnosis and Therapeutical Physics，the Beijing Key Laboratory of Medical Physics & Engineering，Peking University，Beijing 100871，China Institute of Heavy Ion Physics，the Research Center for Tumor Diagnosis and Therapeutical Physics，the Beijing Key Laboratory of Medical Physics & Engineering，Peking University，Beijing 100871，China General Hospital of PLA，Beijing 100085，China

Two parallel methods for magnetic resonance tmaging (MRI) using radio frequency (RF) phased array surface coiks, named spatial loca! Fourier encoding (SLFE) and spatial RF encoding (SRFE), are presented. The MR signals are acquired from separate channels across the coils, each of which covers a sub-FOV (field-of-view) in a parallel fashion, and the acquired data are combined to form an image of entire FOV. These two parallel encoding techniques can accelerate MR imaging greatly, yet associated artifact rnay appear, al-though the SLFE is an effective image reconstruction method which can reduce the localized artifact in some degrees. By the SRFE, RF coil array can be utilized for spatial encoding through a specialized coil design. The images are acquired in a snapshot with a high signal-to-noise ratio (SNR) without the costly gradient system, resulting in great saving of cost. Both mutual induction and aliasing effect of adja-cent coils are critical to the success of SRFE. The strategies of inverse sourc

关键词： MRI radiofrequency phased-array.

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砂藓属植物抗逆特性及相关功能基因研究进展

高师理科学刊 2024年第5期44卷 87-92页

作者：王晶晶白玉蔡璨康必达沙伟张梅娟彭疑芳马天意齐齐哈尔大学生命科学与农林学院黑龙江齐齐哈尔161006 齐齐哈尔大学抗性基因工程与寒地生物多样性保护实验室黑龙江齐齐哈尔161006

作为植物演化过程中的先锋植物,苔藓植物有其特殊适应机制来应对环境的变化,能在其他植物不能生长的极端环境中生长.砂藓属(Racomitrium)植物是典型的耐脱水藓类,能在裸露的岩石表面和沙土上生长.砂藓属植物广泛分布于世界各地,其抗逆... 详细信息

作为植物演化过程中的先锋植物,苔藓植物有其特殊适应机制来应对环境的变化,能在其他植物不能生长的极端环境中生长.砂藓属(Racomitrium)植物是典型的耐脱水藓类,能在裸露的岩石表面和沙土上生长.砂藓属植物广泛分布于世界各地,其抗逆性研究和抗逆基因的挖掘越来越受关注,且目前已取得了一些进展,多个砂藓属植物中的基因已被克隆并进行了抗旱和抗高温功能的验证.对近年来砂藓属植物的抗逆功能进行概述,包括抗旱、耐高温、重金属富集等,旨在为后续砂藓属植物抗逆性研究提供参考依据.

关键词：砂藓属植物植物逆境胁迫抗逆性基因

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