网络环境下促销及口碑对冲动购买的影响——基于情景模拟法的因子探析

本文基于文献梳理和深度访谈,提出了网络背景下促销及网络口碑对冲动购买作用的研究模型,并采用情景模拟法,设计多因子组间实验探讨促销、网络口碑及二者的交互作用对冲动购买的影响,以及冲动特质和产品涉入是否干扰促销及网络口碑对冲动购买的作用

闽商文化的传承与传播及其对青年的影响——以福建省大学生创新创业的视角分析

闽商是我国传统的十大商帮之一,闽商精神是闽商文化的内核,其在推动福建省经济社会发展,促进福建省青年创业发挥了不可替代的作用。笔者以福建省大学生创新创业的视角,分析闽商文化的传承与传播及其对青年的影响,提出福建省大学生继承发扬闽商文化的传播策略:充分利用台湾优秀资源、从文化创意产业着手创新、网络红利为创业助力等。福建省教育厅2016年福建省中青年教师教育科研项目“互联网+时代福建省大学生文化创意产业创新创业研究”结题成果,编号:JAS16039

Influence of Intercalated Li on Electronic Structures and Optical Properties of V_2O_5

采用第一性原理局域密度近似法计算了V2O5的电子态密度和能带结构以及Li嵌入后对其电子结构和光学性质的影响。计算结果表明,V2O5是间接带隙半导体,Li的嵌入并没有改变其电子的跃迁方式。但Li的嵌入使得V2O5导带能量下移,禁带宽度减小,导带中原有的劈裂被分裂的能级填满;同时致使价带出现展宽。电子态密度计算结果表明Li的嵌入对临近的O和V的电子结构有较大的影响。Li2s电子的注入提高了V2O5的费米能级并导致其进入导带。由于价带中的电子只能跃迁到费米能级以上的导带空能级,这致使体系实际的光学带隙增大。同时随着Li注入量的进一步增加,价带的展宽更为明显,费米能级亦呈升高的趋势,使得光学带隙随着Li注入量的增加而增大。The density of states and band structures of α-V2O5 and Li-intercalated V2O5 (LixV2O5, x= 0.5 and 1.0) have been studied using a first-principles calculation based on density function theory with the local density approximation. The results indicate that V2O5 is an indirect-gap semiconductor; the intercalation of Li will not change its way of electron transition. While, the intercalation of Li lowers the energy of conduction band, and then narrows the band gap. At the same time, due to the intercalation of Li, the split-off in the conduction band of V2O5 disappears because of the split of conduction band. The Fermi level of LixV2O5 increases dramatically due to the electron transfer from Li 2s to the V2O5 host, which is probably the main reason why the optical band-gap augments with the Li intercalation.国家重点基础研究发展规划(001CB610505);; 国家自然科学基金(60376015,60336020);; 福建省青年人才创新基金(2005J005)资助项目~

CDK5-dependent BAG3 degradation modulates synaptic protein turnover

阿尔茨海默病（AD）是严重威胁人类健康的重大神经系统疾病，AD的发生发展与衰老密切相关，目前临床治疗方法十分有限。因此迫切需要从AD致病早期入手，发现和鉴定导致AD神经功能紊乱的机制和靶点，为AD的早期防治提供基础。张杰教授及其团队从高通量磷酸化蛋白质组学入手，系统研究了CDK5在神经细胞中的磷酸化底物，鉴定出了在蛋白质量控制中发挥重要功能的BAG3蛋白是CDK5的全新底物。课题组从磷酸化蛋白质组学入手，发现和阐明了细胞周期蛋白激酶5（CDK5）通过调控BAG3在维持突触蛋白水平调控中的作用机制，及其在阿尔茨海默病（AD）发生发展中的机理。 该研究是多个团队历时8年合作完成的，香港中文大学的周熙文教授、美国匹兹堡大学的Karl Herrup教授、美国Sanford-Burnham研究所的许华曦教授、美国梅奥医学中心的卜国军教授，厦门大学医学院的文磊教授、张云武教授、赵颖俊教授、薛茂强教授，军事医学科学院的袁增强教授等都参与了该工作。 厦门大学医学院2012级博士生周杰超等为文章的第一作者，张杰教授为通讯作者。Background Synaptic protein dyshomeostasis and functional loss is an early invariant feature of Alzheimer’s disease (AD), yet the unifying etiological pathway remains largely unknown. Knowing that cyclin-dependent kinase 5 (CDK5) plays critical roles in synaptic formation and degeneration, its phosphorylation targets were re-examined in search for candidates with direct global impacts on synaptic protein dynamics, and the associated regulatory network was also analyzed. Methods Quantitative phospho-proteomics and bioinformatics analyses were performed to identify top-ranked candidates. A series of biochemical assays were used to investigate the associated regulatory signaling networks. Histological, electrochemical and behavioral assays were performed in conditional knockout, shRNA-mediated knockdown and AD-related mice models to evaluate its relevance to synaptic homeostasis and functions. Results Among candidates with known implications in synaptic modulations, BCL2-associated athanogene-3 (BAG3) ranked the highest. CDK5-mediated phosphorylation on Ser297/Ser291 (Mouse/Human) destabilized BAG3. Loss of BAG3 unleashed the selective protein degradative function of the HSP70 machinery. In neurons, this resulted in enhanced degradation of a number of glutamatergic synaptic proteins. Conditional neuronal knockout of Bag3 in vivo led to impairment of learning and memory functions. In human AD and related-mouse models, aberrant CDK5-mediated loss of BAG3 yielded similar effects on synaptic homeostasis. Detrimental effects of BAG3 loss on learning and memory functions were confirmed in these mice, and such were reversed by ectopic BAG3 re-expression. Conclusions Our results highlight that neuronal CDK5-BAG3-HSP70 signaling axis plays a critical role in modulating synaptic homeostasis. Dysregulation of the signaling pathway directly contributes to synaptic dysfunction and AD pathogenesis.This work was supported by the National Science Foundation in China (Grant: 31571055, 81522016, 81271421 to J.Z.; 81801337 to L.L; 81774377 and 81373999 to L.W.); Fundamental Research Funds for the Central Universities of China-Xiamen University (Grant: 20720150062, 20720180049 and 20720160075 to J.Z.); Fundamental Research Funds for Fujian Province University Leading Talents (Grant JAT170003 to L.L); Hong Kong Research Grants Council (HKUST12/CRF/13G, GRF660813, GRF16101315, AoE/M-05/12 to K.H.; GRF16103317, GRF16100718 and GRF16100219 to H.-M,C.); Offices of Provost, VPRG and Dean of Science, HKUST (VPRGO12SC02 to K.H.); Chinese University of Hong Kong (CUHK) Improvement on Competitiveness in Hiring New Faculty Funding Scheme (Ref. 133), CUHK Faculty Startup Fund and Alzheimer’s Association Research Fellowship (AARF-17-531566) to H.-M, C. 该研究受到了国家自然科学基金、厦门大学校长基金、福建省卫生教育联合攻关基金等的资助

Effects of Site-selective Ga-N Codoping on p-type Doping Efficiency of Wurtzite ZnO

采用第一性原理和密度泛函理论的方法,计算未掺杂、N单掺杂和Ga-N共掺杂纤锌矿结构ZnO的总能、电荷密度和能带结构。总能计算表明,Ga原子的共掺杂使总能极大地降低,从而显著提高杂质N原子在ZnO中的稳定性。电荷密度分布显示,总能的降低主要是Ga-N共掺杂后Ga原子的3d态和N原子的2p态电子之间的强杂化相互作用所致。特别是在Ga原子的负电荷和N原子的正电荷沿c轴排成一线的共掺杂构型中,较大的局域极化场的变化引起价带顶向禁带中的大分裂,降低了N受主的激活能,将空穴的浓度提高了三个量级,有效地提高p型掺杂效率。ZnO has become a promising material for ultraviolet light emitting diodes and lasers, transparent high power electronic devices dut to their wide direct band gap and large exciton binding energy. Undoped ZnO exhibits intrinsic n-type conductivity, and it is, therefore, difficult to achieve p-type ZnO. Among group-V dopants, N is considered to be a shallow p-type impurity; however, there are still many difficulties for using N as dopant. Recently, much effort has been devoted to fabricate p-type ZnO with codopants. So it is important to understand the codoping effect on electronic structures of wurtzite ZnO. N dopant stability and p-type doping efficiency of wurtzite ZnO were investigated by calculating the total energies, charge densities and band structures. The differences of total energy between the undoped configuration and N mono-doped, Ga-N codoped configuration Ⅰ and Ⅱ are ΔE_ T-N =1.22 eV, ΔE_ T-Ⅰ =-2.89 eV and ΔE_ T-Ⅱ =-2.84 eV, respectively. This shows that the N dopant stability is improved by Ga codopant. This result is attributable to the strong hybridization between the Ga 3d and N 2p states according to the induced charge density differences. Furthermore, the polarization is significantly changed in the Ga-N codoped configuration Ⅱ where the negative charges of the Ga atom and the positive charges of the N atom align along the c-axis. The energy band structures are thus clearly influenced. The twofold-degenerate Γ_ 5ν level of the top of the valence band for undoped ZnO splits into Γ_ 9ν and Γ~ (1) _ 7ν levels and shifts into the band gap to further separate with the non-degenerate Γ_ 1ν level (labelled as Γ~ (2) _ 7ν ). Then the activation energy of the N acceptor is lowered due to the splitting of the top of the valence band. Finally, according to the relationship between the hole concentration and the activation energy, the hole concentration under the modulation of configuration Ⅱ is enhanced more than three orders of magnitude.国家自然科学基金(60376015, 90206030, 60336020, 10134030);; 国家“973”计划(001CB610505);; 福建省科技计划(2004H054, E0410007)资助项

AN CLUSTER ALGORITHM FOR THE DATASET WITH MIXED ATTRIBUTES AND APPLICATION TO COMPUTER DYNAMIC FORENSIC

针对目前基于k-MEAnS算法的计算机取证技术存在对符号类型数据处理能力欠缺、误报率较高的问题,提出了一种处理混合型属性的聚类算法的计算机取证技术.该方法将对符号类型特征进行编码映射,并使用主成分分析对编码后增加的维数进行降维,从而解决了在计算机取证中使用聚类分析无法对符号型数据进行处理的问题.文中详细的阐述了改进的具体实现方案,并通过实验验证了该方法的可行性.This paper analyses the exists problems of the current computer dynamic forensic techniques base on K-Means algorithm: can not analysis the feature composed by character,higher false-detection rate,etc,brings forward some improvement.We transform the feature of character to numerical value by mapping,then use the technique of Principal Components Analysis to reduce increased dimensionality after mapping.In this paper,we introduce the improved method concretely,and show the feasibility and effect through an experiment.福建省自然基金项目(2008F50602);福建省自然基金-青年人才项目(2008F3101)的支

Stable Geometrical and Electronic Structrues of Wurzite ZnO(0001)-Zn and(000-1)-O Polar Surfaces

采用超高真空分子束外延和扫描隧道显微(STM)技术,对纤锌矿结构znO单晶(0001)-zn和(000-1)-O极性表面进行了STM形貌扫描和扫描隧道谱(STS)测量.STM表征结果显示,(0001)-zn极性表面形成了以单层高度交替出现的直线型和锯齿型台面的大表面纳米稳定结构,还通过形成(3x3)再构表面来稳定其表面.而(000-1)-O极性表面则形成了双层高度台面的表面稳定结构.STS测量结果表明,(0001)-zn极性表面内部偶极矩方向指向表面,而(000-1)-O极性表面内部偶极矩方向指向材料内部,导致两种极性表面能带的弯曲方向不同,最终引起两者导带底EC和价带顶EV能量位置的偏移.(0001)-zn和(000-1)-O极性表面I-V和dI-dV曲线的偏移体现了两种表面的不同极性和电子结构性质.Geometrical and electronic structures of wurtzite ZnO(0001)-Zn and(000-1)-O polar surfaces have been examined carefully by using an Omicron molecular beam epitaxy(MBE)and scanning tunneling microscopy(STM)combined system operated in ultra-high vacuum(UHV).STM measurements showed that(0001)-Zn polar surface tends to form the stable alternating straight and zigzag countertops with the double-layer step.In some areas there exist the(3×3)surface reconstruction.Different from the stabilization mechanism of(0001)-Zn polar surface,(000-1)-O polar surface can be stabilized by forming the double double-layer step countertops with the large flat surface.Furthermore,current-voltage properties measured by scanning tunneling spectroscopy(STS)indicate that,the conduction band bottomECand the valence band top EVof(000-1)-O polar surface shifts to the higher energy as compared with that of(0001)-Zn polar surface.The shifting of EC and EVis apparently attributed to different dipole moments of the(0001)-Zn and(000-1)-O polar surfaces and indicates the different polarity of two polar surfaces.国家自然科学基金(91321102;11304257;61227009); 福建省自然科学基金(2011J05006;2009J05149;2014J01026); 福建省教育厅资助项目(JA09146); 黄慧贞集美大学学科建设基金资助项目(ZC2010014); 集美大学科研启动金项目(ZQ2011008;ZQ2009004

图形衬底上应变SiGe/Si超晶格的结构及光致发光研究

该文研究了在Si的图形衬底上生长应变SiGe/SI超晶格的结构和其光致发光性质。图形衬底由光刻形成的类金字塔结构组成。发现在组成倒金字塔结构的(111)面的交界处有富Ge的SiGe量子线出现。对相同条件下图形衬底和平面衬底上的应变SiGe层的光致发光光谱进行了比较，图形衬底上总的发光强度相对提高了5.2倍。认为这种提高同富Ge的SiGe量子线的产生相关

适应于楼宇环境下运行的新型机器人的设计

设计了一种具有平面内3自由度全方位移动,并且能够被动自适应越过轮子半径近2.5倍垂直障碍的新型机器人。该机器人采用6个驱动轮控制。车身上采用4个Mecanum驱动轮矩形布置,使其具有平面内的全向移动功能。前、后轮采用全向轮,使其能够在原地转弯和横向移动时候与地面保持滚动状态。6个驱动轮分别安装在机体的攀登机构、爬升机构、稳定机构的高架连杆机构上,使其具有很好的爬楼梯和越障功能。给出了一般结构形式全方位移动系统的运动学模型,并得到其实现全方位运动的必要条件是逆雅可比矩阵满秩。优选出了全方位运动系统的最佳结构布局形式。对整个机器人系统在平面内的直行、横行、原地转弯以及爬楼梯等功能进行了虚拟样机系统仿真验证

花键搓齿机设计与分析

针对国内花键搓齿机设计制造过程依靠经验数据与设计支撑理论不充分的现状，以立式花键搓齿机为例，研究其设计分析方法。在搓制成形力计算基础上，给出了立式花键搓齿机的总体布局和床身结构设计；依据模拟仿真获得的成形力数据，并在对滑台、丝杠的工作情况和受力分析基础上，设计了传动系统关键部件；对立式搓齿机进行了强度和模态分析，得到了机床的静动态特性