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Search Results: 1 - 10 of 55067 matches for " 宋亮 "
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“空间数据库原理”课程教学探讨
Discussion on Teaching of “Spatial Database Theory”
 [PDF]

伟伟,
Geomatics Science and Technology (GST) , 2015, DOI: 10.12677/GST.2015.31001
Abstract:
本文分析了当前空间数据库课程教学现状及存在的问题。结合教学实际需求,根据专业自身特点,提出了合理的理论教学与实践教学体系。从优化教材建设、教学内容,丰富教学手段,创新教学方法等多个角度探讨了该门课程可能的教学改革手段,有利于提高《空间数据库原理》课程的教学质量。
The current teaching situation and some problems of spatial database theory are analyzed in this paper. Combining with the actual needs of teaching and its own characteristics, reasonable aca-demic education and practical teaching system are brought up. A discussion is made about proper teaching reform from different perspective, such as optimizing textbook construction, teaching content, enriching teaching methods and so on, which help to improve the teaching quality of spa-tial database theory course.
不同盐渍条件下刺参体品质的变化及盐渍动力学研究

- , 2016, DOI: 10.13982/j.mfst.1673-9078.2016.10.018
Abstract: 本文研究了在15%盐水、饱和盐水和干盐三种不同盐渍条件下,刺参品质(体壁组织构造、微观结构、流变学特性及质构特性)的变化情况,并探讨了刺参盐渍过程的动力学。采用饱和盐水和干盐盐渍的刺参,随着盐渍时间延长,刺参体壁胶原纤维发生收缩,结构排列趋于紧密,储能模量、损耗模量均逐渐增大,硬度、黏聚性、咀嚼度变大,弹性、回复性逐渐减小;而采用15%盐水盐渍的刺参,在盐渍初期,变化趋势与饱和盐水和干盐盐渍相似,盐渍后期刺参体壁胶原纤维膨胀,组织中空隙增大,储能模量、损耗模量下降,硬度、黏聚性、咀嚼度下降;动力学模型拟合结果表明,高盐度处理的刺参体壁,其盐渍过程符合单向正渗透原理。本研究表明了不同盐渍条件对刺参品质产生了明显的影响,可为刺参盐渍条件的确定提供科学依据。
The changes in the quality of sea cucumber (tissue structure of body wall, microstructure, rheological properties and textural properties) under three salting conditions (15% salt solution, saturated salt solution, and dry salt) were studied in this work, and the evolution kinetics during the salting of sea cucumber were explored. When the sea cucumber samples were treated with saturated salt solution and dry salt, the shrinkage of collagen fibers of sea cucumber body wall occurred, and the structural arrangement tended to became denser. Meanwhile, the storage modulus and loss modulus gradually increased. The hardness, cohesiveness, and chewiness increased, and the elasticity and resilience gradually decreased. When the sample was treated in 15% salt solution, the trend of the changes during the early stage of the salting process was similar to those in the saturated salt solution and dry salt. At the late stage of salting process, collagen fibers of sea cucumber body wall swelled, the spaces of tissue structure increased, and the storage modulus, loss modulus, hardness, cohesiveness, and chewiness decreased. The results of kinetic fitting model indicated that, for the body wall of sea cucumbers treated with high salinity, the salting process followed the principle of one-direction forward osmosis. This study indicates that the different salting conditions have significant impacts on the quality of sea cucumbers, and can provide a scientific basis for the determination of the salting conditions for sea cucumber.
我国环境会计假设研究述评

财会月刊 , 2005,
Abstract:   近年来,随着环境问题的日益突出,我国环境会计理论研究空前繁荣。和会计领域其他问题的研究一样,环境会计研究也必须首先明确会计假设等基本理论问题。只有这样,才能对环境会计理论体系中其他问题展开深入研究。  一、我国环境会计假设研究的现状环境会计假设作为环境会计概念框架的基础,同传统会计的假设是否一致呢?国内不少学者对此进行过探讨。对于持续经营和会计分期假设,大家的看法是一致的,认为其内涵无需做出变动,在环境会计中可以继续采用。  1.会计主体假设。对于该假设的探讨,主要集中在两个方面。一方面是核算内容。不少学者认为,在环境会计核算中,不仅要计量、考核和报告会计主体自身的经营成果,而且要计量、考核和报告会计主体的生产经营活动对社会环境的影响。也就是说,企业应当把由于生产经营活动而产生的外部不经济性亦纳入会计核算(赫连诚,2002)。
巢湖西滨杭埠地区地下水环境质量分析评价

地质论评 , 2015,
Abstract:
海参肽的分离纯化及其对NIH/3T3细胞胶原蛋白分泌的影响

- , 2017, DOI: 10.13982/j.mfst.1673-9078.2017.3.004
Abstract: 本论文从刺参中分离纯化得到一种海参肽,并研究其对NIH/3T3细胞增殖和胶原蛋白分泌的影响。采用活性追踪的方法从新鲜刺参中通过离子交换层析、凝胶层析分离纯化得到海参肽SP12,采用MTT法检测SP12对NIH/3T3细胞的增殖作用;采用流式细胞术检测SP12对NIH/3T3细胞细胞周期的影响;采用羟脯氨酸测定试剂盒的方法检测SP12对NIH/3T3细胞胶原蛋白分泌的影响;采用Western Blot及RT-PCR的方法,在蛋白水平及基因水平上检测SP12对NIH/3T3细胞I型胶原蛋白、MMP-1及TIMP-1表达的影响。结果表明SP12能显著提高NIH/3T3细胞的增殖率,能促进NIH/3T3细胞由G1期向S期转变,增加其胶原蛋白的分泌量,且在0~20 μg/mL范围内均呈剂量依赖性。在蛋白水平和基因水平,SP12均能显著促进I型胶原蛋白及TIMP-1的表达,抑制MMP-1的表达,这可能是SP12促进NIH/3T3细胞胶原蛋白分泌的作用机制。
A sea cucumber peptide, SP12, was isolated and purified from Stichopus japonicus, and its impact on NIH/3T3 cell proliferation and secretion of type I collagen was studied. SP12 was purified by ion exchange chromatography and gel filtration chromatography from fresh Stichopus japonicus using a cell activity tracking method. The effect of SP12 on NIH/3T3 cell proliferation was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and its impact on cell cycle progression was determined by flow cytometry. The effect of SP12 on collagen secretion by NIH/3T3 cells was measured by hydroxyproline kit, and its impact on the expression of type I collagen, matrix metalloproteinase-1 (MMP-1), and tissue inhibitor of metalloproteinases-1 (TIMP-1) in NIH/3T3 cells was measured at the protein and gene levels by western blot and reverse-transcription polymerase chain reaction (RT-PCR). The results clearly demonstrate that SP12 can considerably enhance the proliferation rate of NIH/3T3 cells and promote progression from G1 phase to S phase. In a range of 0~20 μg/mL, SP12 enhanced collagen secretion by NIH/3T3 cells in a dose-dependent manner. At the protein and genetic levels, SP12 considerably promoted the expression of type I collagen and TIMP-1, and inhibited the expression of MMP-1; this might be the mechanism underlying SP12 promotion of collagen secretion by NIH/3T3 cells.
移动荷载作用下沥青路面应力响应的持续时间
小金,
- , 2018,
Abstract: 在实测4种沥青路面结构应力响应的基础上,系统研究了行车速度与不同深度下的荷载响应持续时间的关系。研究结果表明,行车荷载沿路线方向的应力影响的有效长度在速度为20 km/h左右时存在峰值,沥青结构层内应力响应的持续时间与行车速度、深度存在显著的非线性关系。通过非线性数据拟合,得到了行车速度大于20 km/h时的荷载时间与荷载速度和结构深度的关系式,该公式意义明确,相对于已有的理论方法,其拟合精度大为提高。对大于20 km/h的行车速度与路面荷载频率之间的关系进行分析,建立了行车速度与不同路面深度的荷载频率的关系,为室内试验有效模拟行车荷载提供了依据。
Based on the measured stress response of 4 kinds of asphalt pavement structures, the relationship between the driving speed and the load response duration under different depths was systematically studied. The results show that the effective length of the impact of the traffic load along the route direction has a peak at the speed of about 20km/h. There is a significant nonlinear relationship between the duration of the stress response in the asphalt structure and the speed and depth of the traffic. Through the nonlinear data fitting, the relationship between the load time and the load velocity and the structural depth when the driving speed is greater than 20km/h was obtained. The formula has clear meaning, and the fitting accuracy is greatly improved compared with the existing theoretical methods. The relationship between the driving speed of more than 20km/h and the road load frequency was analyzed, and the relationship between the driving speed and the load frequency of different pavement depth was established, which provides a basis for the effective simulation of the driving load in the laboratory.
60°坐标系下新型模块化多电平变流器空间矢量脉宽调制的简化通用算法 A simple generalized algorithm of space-vector PWM for a new type of modular multilevel converter based on 60° coordinate system
,熊博
- , 2017,
Abstract: 对任意电平逆变器在60°坐标系下的空间矢量脉宽调制通用算法进行研究;并在此基础上推导出了多电平与两电平电压矢量之间的作用时间矩阵;为了减小输出电压波形畸变率,降低开关的损耗,对冗余电压矢量的选择方法和最优合成顺序进行了确定,最后,在PSIM中搭建了模块化多电平的仿真模型,并将基于60°坐标系的空间矢量调制算法用程序实现,证明该简化算法的通用性和正确性,仿真实验也证明随着电平数的增加,输出线电压波形越接近正弦波
产复合酶枯草芽孢杆菌qlb6的激光诱变育种
,,
食品科学 , 2011,
Abstract: ?以产复合酶枯草芽孢杆菌qlb6为出发菌株,利用氦-氖(he-ne)激光进行诱变育种。通过计算存活率和正突变率,确定激光诱变育种的照射剂量。通过透明圈筛选和酶活力测定,筛选获得1株编号为qlb6f的菌株,其纤维素酶、蛋白酶、淀粉酶酶活力相对于出发菌株分别提高219%、38%和71%。进行30代遗传稳定性实验,证明它具有良好的遗传稳定性,无回复突变。
一种p2p网络安全的信誉度模型设计
金龙,董健全,
计算机应用 , 2006,
Abstract: ?通过建立一种信誉度模型来隔离恶意节点,保证网络安全可靠并能够提供更好质量、更加有效的服务。从信誉角度构造了一个安全的p2p网络,给出了求解信誉度的数学模型和具体算法以及决定信誉度的一些因素,并进行了实验模拟分析,验证此信誉度模型能够有效隔离恶意节点。
生育行为对老年女性健康的影响
Fertility Behavior and Elderly Women’s Health

月萍,
- , 2016,
Abstract: 摘要 立足于老龄化和生育政策调整的背景,文章利用中国健康与养老追踪调查数据,通过建立加速时效时间模型,系统分析了包含子女数量、性别结构、生育时间和生育期长等在内的生育行为对女性进入老年时期的健康的影响,并进一步在个体层面上测算了老年女性的健康生存时间。实证结果发现,生育行为对老年女性的健康会产生重要影响。从健康角度来看,生男生女都一样;而多子不但不会多福,还会降低老年女性的健康福利;同时,初育年龄太大或太小都将不利于女性老年时期的健康水平,而生育期延长会显著提升女性老年时期的健康水平。文章还探讨了生育行为对老年女性健康的影响机制,认为在目前生育政策调整的背景下应关注生育行为改变对女性健康的潜在影响。
Abstract: Based on data from China Health and Retirement Longitudinal Survey and treating fertility as a unique event in women’s life,this paper explores the impact of fertility behavior-number of children,gender structure,and fertility timing and intervals on elderly women`s health,and estimates the healthy survival time of elderly women by using the accelerated failure time model.Results show that fertility behavior significantly influences elderly women’s health.In a health perspective,more children would reduce happiness.Less number of children,appropriate age at childbearing and longer birth intervals significantly increase healthy survival time.The paper further discusses the mechanisms through which fertility behavior impact elderly women’s health,and points out that public policy should pay more attention to the potential impact of changing fertility behavior on women’s health in the context of implementing a two-child policy.
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