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准稳态下常功率平面热源法测不良热导体热导率及COMSOL模拟
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作者 方奕忠 沈韩 +4 位作者 崔新图 黄臻成 冯饶慧 廖德驹 庞晓宁 《物理与工程》 2023年第5期87-94,共8页
准稳态法是测量不良热导体热导率的一种常用方法,样品材质、保温层、加热功率等都会对测量结果造成影响。本文采用分离变量法,以有机玻璃为例,求解了厚度均匀的无限大不良热导体两侧同时施加均匀的指向中心面的热流密度时的热传导方程,... 准稳态法是测量不良热导体热导率的一种常用方法,样品材质、保温层、加热功率等都会对测量结果造成影响。本文采用分离变量法,以有机玻璃为例,求解了厚度均匀的无限大不良热导体两侧同时施加均匀的指向中心面的热流密度时的热传导方程,得到样品各处的温度随时间变化的严格解。在初始加热时间不到十分钟的状态下采用截断近似,并在准稳态下用常功率平面热源加热法测量了不良热导体的热导率k及比热c。在此基础上,采用四块有机玻璃板和两个加热薄膜外包泡沫和聚丙烯(PP)阻热材料的模型,作了COMSOL多物理场耦合仿真,得到的理论、实验及仿真结果三者符合得很好。 展开更多
关键词 准稳态 不良热导体 热导率 虚实结合 COMSOL仿真模拟
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辽宁省棉花区域试验2013―2022年工作回顾与展望 被引量:1
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作者 韩晓军 王洪山 王子胜 《中国棉花》 2023年第6期28-30,共3页
简要回顾了1949―2022年辽宁省棉花品种区域试验的发展历程,总结了2013―2022年辽宁省棉花品种区域试验基本操作规程、试验操作的变化和工作经验,并对今后的区域试验工作提出一些建议。
关键词 辽宁省 棉花 区域试验 特早熟 品种推广 操作规程
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中国商贸产业发展与结构变动的趋势研究 被引量:2
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作者 晏维龙 胡荣华 +1 位作者 han Yao 《产业经济研究》 2001年第1期39-44,共6页
本文根据中国商贸产业发展的历史与逻辑,分析商贸发展与经济发展、城市发展,商贸发展中的内部结构、市场结构、产权结构、组织结构、业态结构、经营结构、技术结构的变化与调整等问题.
关键词 中国商贸产业 结构变动 趋势
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论大学生心理健康教育 被引量:5
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作者 韩苏蓉 han Su-rong 《西南民族学院学报(哲学社会科学版)》 北大核心 2002年第9期226-229,共4页
全文分为四部分 ,讨论了大学生心理健康的含义和七条基本标准 ,对处在青春期的大学生群体四个方面的心理特点和常见的六种心理障碍作了较为深入的分析 ,对当前心理健康教育中存在的三个主要问题给予了阐述 。
关键词 大学生 心理健康教育 学科教学 思想道德修养课 师资建设 自我教育
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谷物中的霉菌及霉菌毒素 被引量:3
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作者 胡兰 LIU +2 位作者 Li-xia han Ya-dong 《辽宁农业科学》 2001年第2期35-37,共3页
关键词 谷物 霉菌污染 霉菌毒素
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网络环境下渐开线齿轮的三维参数化造型
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作者 孙晋萍 韩泽光 +1 位作者 han Ze-guang 《太原理工大学学报》 CAS 北大核心 2005年第2期200-202,共3页
论述了基于网络环境下进行渐开线圆柱齿轮三维参数化特征造型的设计思想,将轮齿与轮体分别按特征分类,实现了直齿、斜齿、螺旋齿齿轮三维造型的统一,解决了特殊齿形和齿向曲线实体造型的难点。为其他零件三维建模提供了一种有效实用的... 论述了基于网络环境下进行渐开线圆柱齿轮三维参数化特征造型的设计思想,将轮齿与轮体分别按特征分类,实现了直齿、斜齿、螺旋齿齿轮三维造型的统一,解决了特殊齿形和齿向曲线实体造型的难点。为其他零件三维建模提供了一种有效实用的方法。 展开更多
关键词 齿轮 参数化特征造型 三维建模 网络环境
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EPR Study of a New Crystal of the Binuclear Copper(Ⅱ) Cluster Compound- Cu_2(α-C_(10)H_7CH_2CO_2)_4-(DMF)_2 ·(DMF)_2·H_2O
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作者 孙琼丽 han Shi-Yi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1994年第1期9-15,共7页
In this paper, single crystal EPR study of a new binuclear copper (Ⅱ) cluster compound-[Cu2(α-C(10) H7CH2CO2)4 (DMF)2]·[DMF]2·H2O](DMF= (CH3)2NCOH) at room temperature is reported. The lines of △Ms=±... In this paper, single crystal EPR study of a new binuclear copper (Ⅱ) cluster compound-[Cu2(α-C(10) H7CH2CO2)4 (DMF)2]·[DMF]2·H2O](DMF= (CH3)2NCOH) at room temperature is reported. The lines of △Ms=±1 allowing transition and △M=2 forbiding transition are shown in EPR spectra. The experimental data are consistent with the calculated results by the leastsquares fitting prograrn in three principal planes of g and D tensors. The spin Hamiltonian parameters are as follows: gx=2. 1482, gy=2. 0529 ,gz=2. 3905, D= 0. 348 cm ̄(-1) and E =0. 01 cm-1. The diagrams of the energy levels have been obtained when the magnetic field is oriented to three principal axes. The polycrystal EPR spectra have been measured at room temperature and 77K, respectively.and the parameters of these spectra are given (g∥= 2. 094, g⊥= 2. 425, D= 0. 37 cm-1,E=0). The parameter of the isotropic magnetic exchange interaction J=-254cm-1 is determined, and that of the anisotropic magnetic exchange J1=-153 cm-1 is calculated. The average magnetic susceptibility of the polycrystal sample χ= 1. 39 ×10-6 (c. g. s) has been measured by Faraday powder method. Thus the average magnetic mornent μ=1. 43 B. M. can be calculated. It is shown that the exchange interactions between the metal ions of the binuclear copper(Ⅱ) cluster compound are confirmed antiferromagnetic In nature. 展开更多
关键词 EPR spectroscopic binuclear copper cluster spin parameter magnetic exchange
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基于PLC的GTD-350燃气轮机起动控制 被引量:2
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作者 谢春玲 韩云辉 +6 位作者 赵鹏 ZHAO Peng han Yun-hui XIE Chun-lin 《燃气轮机技术》 2005年第1期60-62,共3页
在GTD-350燃气轮机起动系统中,用可编程控制器(PLC)起动系统控制电路设计起动的时序逻辑控制程序,实现了燃气轮机起动过程的自动控制。
关键词 GTD-350燃气轮机 可编程控制器 起动系统
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Synthesis, Crystal Structure and Biological Activity of a Novel Amino Acid Salt (HGly)_4[HPMo_(12)O_(40) ]_2·22H_2O 被引量:4
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作者 han Zheng-bo +2 位作者 ChanG Ya-ping 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期15-19,共5页
A novel compound, (HGly) 4[HPMo 12 O 40 ] 2·22H 2O, was synthesized and characterized by means of elemental analysis, IR and X ray diffraction. The compound crystallized in a monoclinic space group ... A novel compound, (HGly) 4[HPMo 12 O 40 ] 2·22H 2O, was synthesized and characterized by means of elemental analysis, IR and X ray diffraction. The compound crystallized in a monoclinic space group Cc with a =4 0060(0 8) nm, b =1 2527(0 3) nm, c =1 9930(0 4) nm, β =96 36(3)°, V =9 940(3) nm 3, Z =2, R 1=0 0576, wR 2 =0 1746. The anti tumor activity of this compound was tested in two human tumor cell lines in vitro . 展开更多
关键词 POLYOXOMETALATE GLY Crystal structure Biological activity
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Seismotectonic environment of occurring the February 3, 1996 Lijiang M=7.0 earthquake, Yunnan Province 被引量:4
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作者 han Zhu-jun(韩竹军) +7 位作者 GUO Shun-min(虢顺民) XIANG Hong-fa(向宏发) ZhanG Jia-sheng(张家声) RAN Yong-kang(冉勇康) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第4期453-463,共11页
Lijiang-Daju fault, the seismogenic fault of the 1996 Lijiang M=7.0 earthquake, can be divided into Lijiang-Yuhu segment in the south and Yuhu-Daju segment in the north. The two segments show clear difference in geolo... Lijiang-Daju fault, the seismogenic fault of the 1996 Lijiang M=7.0 earthquake, can be divided into Lijiang-Yuhu segment in the south and Yuhu-Daju segment in the north. The two segments show clear difference in geological tectonics, but have the similar dynamic features. Both normal dip-slip and sinistral strike-slip coexist on the fault plane. This kind of movement started at the beginning of the Quaternary (2.4~2.5 Ma B.P.). As to the tectonic types, the detachment fault with low angle was developed in the Early Pleistocene and the normal fault with high angle only after the Mid-Pleistocene (0.8 Ma B.P.). Based on the horizontal displacements of gullies and the vertical variance of planation surfaces cross the Lijiang-Daju fault at east piedmont of Yulong-Haba range, the average horizontal and vertical slip rates are calculated. They are 0.84 mm/a and 0.70 mm/a since the Quaternary and 1.56 mm/a and 1.69 mm/a since the Mid-Pleistocene. The movements of the nearly N-S-trending Lijiang-Daju fault are controlled not only by the regional stress field, but also by the variant movement between the Yulong-Haba range and Lijiang basin. The two kinds of dynamic processes form the characteristics of seismotectonic environment of occurring the 1996 Lijiang earthquake. 展开更多
关键词 the 1996 Lijiang earthquake variant movement basin boundary fault seismotectonic envi-ronment
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Modification of Montmorillonite through Intercalative Polymerization 被引量:3
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作者 Lin Jie +3 位作者 ZHI Bing han 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第1期108-109,共2页
Montmorillonite (MMT) was modified through intercalative polymerization of phenol and formaldehyde catalyzed by oxalic acid. The modified montmorillonite was delaminated at large, as demonstrated by XRD and TEM studi... Montmorillonite (MMT) was modified through intercalative polymerization of phenol and formaldehyde catalyzed by oxalic acid. The modified montmorillonite was delaminated at large, as demonstrated by XRD and TEM studies. It can disperse easily in epoxy resin to form exfoliated nanocomposites. The nanoscale silicate platelets dispersed in water can be metallized by silver deposition. 展开更多
关键词 MONTMORILLONITE intercalative polymerization novolac resin nanocomposites.
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The Popularization and Application of Cold Storage Red Blood Cells or Whole Blood at -80 ℃ of the Rh(D) Negative Patients in Surgical Operation 被引量:3
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作者 YU Zhongqing(余忠清) +7 位作者 HU Lihua(胡丽华) han Min(韩敏) RAO Shenzong(饶神宗) LUO Chengwei(罗成伟) 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2002年第2期155-157,共3页
Summary: The efficiency of cold storage red blood cells (CSRBC) or whole blood at -80 ℃ used in 27 Rh(D) negative patients during surgical operation was reported. The Rh(D) negative patients received the transfusion... Summary: The efficiency of cold storage red blood cells (CSRBC) or whole blood at -80 ℃ used in 27 Rh(D) negative patients during surgical operation was reported. The Rh(D) negative patients received the transfusion of CSRBC or whole blood stored at -80 ℃ for 180 to 360 days. The changes in the indexes, such as blood TB, DB, K +, Na +, BUN, Cr, urine protein (URPO), UOB, Hb, HCT, serum total protein, relative to hemolytic reaction and blood volume before and after transfusion were observed. The results showed that after transfusion of CSRBC or whole blood 27 cases were negative for urine protein and UOB, and the levels of BUN and Cr were normal (P>0.05). Blood TB, DB, Hb, and HCT were increased, while pH, blood K + and blood Na + was normal with the difference being not significant before and after operation (P>0.05). Plasma protein was decreased, but there was no significant difference before and after operation (P>0.05). It was suggested that CSRBC or whole blood at -80 ℃ could be safely infused to the Rh(D) negative patients without side effects during the surgical operation. 展开更多
关键词 Rh(D) negative patient -80 cold storage red blood cells surgical operation hemolytic reaction
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Comparison of Compositions and Structural Characterizations of Synthetic Nano-hydroxyapatite and Mineral Phase from Porcine Femoral Bone 被引量:4
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作者 张利 LI +8 位作者 Yubao WANG Xuejiang Peng Xuelin Zuo Yi han Jimei 《High Technology Letters》 EI CAS 2004年第4期48-51,共4页
In the paper, nano-hydroxyapatite was synthesized by hydrothermal treatment. The crystal morphology and compositions of the synthetic HA were investigated using TEM, IR, XRD and XPS techniques and were compared with t... In the paper, nano-hydroxyapatite was synthesized by hydrothermal treatment. The crystal morphology and compositions of the synthetic HA were investigated using TEM, IR, XRD and XPS techniques and were compared with those of porcine femoral bone apatite. The results showed that the synthetic HA is nanometer rod crystal similar to the bone apatite, and the average crystal sizes calculated by Scherrer equation for the four samples (HA dried at 80℃, unburned bone apatite, HA calcined at 750℃ and bone apatite calcined at 750℃) are 20.6, 21.7, 22.5 and 27.6nm, respectively. Moreover, the essential compositions for the synthetic HA and bone apatite are almost the same. 展开更多
关键词 股骨 矿物 羟磷灰石 分析方法
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Sampled-data Iterative Learning Control for Singular Systems 被引量:3
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作者 孙鹏 FANG +2 位作者 Zhong han Zhengzhi 《High Technology Letters》 EI CAS 2004年第3期70-73,共4页
Sampled-data iterative learning control (SILC) for singular systems is addressed for the first time. With the introduction of the constrained relative degree, an SILC algorithm combined with a feedback control law is ... Sampled-data iterative learning control (SILC) for singular systems is addressed for the first time. With the introduction of the constrained relative degree, an SILC algorithm combined with a feedback control law is proposed for singular systems. Convergence of the algorithm is proved in sup-norm, while the conventional convergence analysis is in λ-norm. The final tracking error uniformly converges to a small residual set whose level of magnitude depends on the system dynamics and the sampling-period. Due to inequalities to estimate the level of the existing results of SILC, convergence is guaranteed not only at the sampling instants but on the entire operation interval, so that the inter-sample behavior is guaranteed, which is more practical for real implementation. 展开更多
关键词 奇异系统 机器人控制 试验数据迭代学习控制 算法收敛
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Isolation and characterization of a lytic bacteriophage φKp-lyy15 of Klebsiella pneumoniae 被引量:1
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作者 Yinyin Lu +9 位作者 Hongyan Shi Zhe Zhang Fang han Jinghua Li Yanbo Sun 《Virologica Sinica》 SCIE CAS CSCD 2015年第1期66-68,共3页
Dear Editor,Bacteriophages(phages)are viruses that specifically infect and kill bacteria.They are ubiquitous throughout all environments that bacteria inhabit.Following their discovery by F.W.Twort in 1915 and F.d’He... Dear Editor,Bacteriophages(phages)are viruses that specifically infect and kill bacteria.They are ubiquitous throughout all environments that bacteria inhabit.Following their discovery by F.W.Twort in 1915 and F.d’Herele in 1917,bacteriophages were recognized as potential agents to treat bacterial diseases and phage therapy has been used 展开更多
关键词 KLEBSIELLA PHAGE inhabit environments ubiquitous PHAGE INFECT anaerobic opportunistic specifically
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Vertical characteristics of ozone variation over the Arctic Chukchi Sea region in 1999 被引量:3
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作者 Zhou Libo +6 位作者 (周立波) Liu Yu (刘宇) Zou han (邹捍) 《Chinese Journal of Polar Science》 2002年第1期75-82,共8页
In 1999 summer, Chinese Arctic Research Expedition operated the Chukchi Sea. On Chinese icebreaker Xuelong, we made many high resolution ozonesonds measurements. During the period from August 18 to 24, a synoptic sca... In 1999 summer, Chinese Arctic Research Expedition operated the Chukchi Sea. On Chinese icebreaker Xuelong, we made many high resolution ozonesonds measurements. During the period from August 18 to 24, a synoptic scale observation was taken at 75°N, 160°W. Using the above data, together with TOMS total ozone and NCEP circulation data, we showed that atmospheric ozone amount experienced a high low high variation, with low high low tropopause altitude. Correlation analysis showed a close relation between the total ozone and ozone below 13 km, while the variation of the maximum concentration at about 20 km didn't show any relation to the column ozone. In 500 hPa height maps, there was also the weak strong weak southwesterly pattern. Therefore we suggested that the synoptic system might be responsible to a low ozone advection during this ozone variation. 展开更多
关键词 ozonesonds TOMS TROPOPAUSE synoptic system.
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Study on distribution characteristics of strong earthquakes in Sichuan-Yunnan area and their geological tectonic background 被引量:1
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作者 han Wei-bin(韩渭宾) +1 位作者 JIANG Guo-fang(蒋国芳) 《Acta Seismologica Sinica(English Edition)》 CSCD 2004年第2期230-243,共14页
In the paper, the distribution characteristics of strong earthquakes in Sichuan-Yunnan area and their geological tectonic background, especially the relation to Sichuan-Yunnan and Sichuan-Qinghai crustal blocks have b... In the paper, the distribution characteristics of strong earthquakes in Sichuan-Yunnan area and their geological tectonic background, especially the relation to Sichuan-Yunnan and Sichuan-Qinghai crustal blocks have been studied. The main results are: a) Strong earthquakes in Sichuan-Yunnan area distribute mainly in Sichuan-Yunnan and Sichuan-Qinghai crustal blocks; b) Most of strong earthquakes of the two blocks distribute mainly along their boundary faults; c) A few strong earthquakes are not obviously related to active faults. It shows that the relation between strong earthquakes and geological tectonics can be very complex; d) There is a certain correlativity for seismic activities among boundary faults of the two blocks, but they have different features; e) There are some anomalous changes of velocity structures in the deep crust of boundary faults of the two blocks. Many boundary faults, especially Longmenshan fault, cut obviously the Moho discontinuity. The Xianshuihe fault, a typical strike-slip fault, has no obvious indication of cutting the Moho discontinuity, but has distinct low-velocity zone in different depths. 展开更多
关键词 Sichuan-Yunnan area SEISMICITY crustal block deep structure
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EFFECTS OF CHRONIC STRESS ON THE ACTIVITIES OF SOD, GSH-Px AND MDA LEVEL IN FEMALE RATS' BRAIN 被引量:1
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作者 Wang Ying(王莹) +9 位作者 Yang Dongwei(杨东伟) Xie Wen(谢雯) Pang Wei(庞炜) Jiang Mali(蒋马莉) han Taizhen(韩太真) 《Academic Journal of Xi'an Jiaotong University》 2002年第2期144-146,共3页
Objective To observe the effects of chronic emotional stress on the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and malonialdehyde (MDA) level in female rats’ brain. Methods The rats ... Objective To observe the effects of chronic emotional stress on the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) and malonialdehyde (MDA) level in female rats’ brain. Methods The rats were randomly divided into 4 groups: normal control group (group N), emotional stress group (group E), emotional stress + pregnancy group (group E+P) and regularly drinking group (group R). Emotional stress in rats was induced by training rats with empty drinking bottles. Having been finished the stress procedure, the brain was taken out and homogenized. Then the activities of SOD, GSH-Px and MDA level were measured. Results Compared to group N, both the activities of SOD in brain tissues of group E and group E+P were significantly decreased ( P <0.05 and P <0.01, respectively) while the MDA level increased ( P <0.05). However, the extent of changes in group E+P was more obvious than that in E. GSH-Px activities in E+P and E were significantly changed. However, the GSH-Px activity in E+P was decreased ( P <0.05) while the activity in E increased ( P <0.05).Conclusion The chronic emotional stress can reduce the antioxidative system by decreasing the antioxidative enzyme activity and potentiating the lipid peroxidation in the brain. It is also suggested that the combination of emotional stress and pregnancy can augment the oxidative damage in rats’ brain. 展开更多
关键词 chronic EMOTIONAL stress oxidative damage lipid PEROXIDE SOD MDA GSH-PX
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Typical Form of Organizational Innovation and Development Trend 被引量:1
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作者 石春生 Fang +4 位作者 Xingdong YANG Cuilan han Xinjuan 《High Technology Letters》 EI CAS 2004年第1期70-72,共3页
Nowadays the organization of enterprises is facing unprecedented change enterprises, and organizational innovation has become a magic weapon to increase enterprise competitieness. This paper analyzes the existing base... Nowadays the organization of enterprises is facing unprecedented change enterprises, and organizational innovation has become a magic weapon to increase enterprise competitieness. This paper analyzes the existing base of institutional framework and suggests several forms and the development trend of institutional framework of organizational innovation at present. 展开更多
关键词 企业 机构改革 市场竞争力 行政联合 顾客服务中心 无结构组织
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Analyses on Four Models and Cases of Enterprise Informatization 被引量:1
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作者 石春生 han +4 位作者 Xinjuan YANG Cuilan ZHAO Dongbai 《High Technology Letters》 EI CAS 2003年第3期75-80,共6页
The basic conditions of the enterprise informatization in Heilongjiang province are analyzed and 4 models are designed to drive the industrial and commercial information enterprise. The 4 models are the Resource Integ... The basic conditions of the enterprise informatization in Heilongjiang province are analyzed and 4 models are designed to drive the industrial and commercial information enterprise. The 4 models are the Resource Integration Informatization Model, the Flow Management Informatization Model, the Intranet E-commerce Informatization Model and the Network Enterprise Informatization Model. The conditions for using and problems needing attentions of these 4 models are also analyzed. 展开更多
关键词 informatization model resource integration intranet e-commerce network enterprise
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