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991.
Apache Struts is one of the most popular open source framework for Web applications and developments using MVC Model2 architectural pattern. Using the Information Technology to improve the efficiency of education service is emergent. The aim of this paper is to demonstrate the design and realization of a platform system software based on Apache Struts framework. By briefly analyzing the extra requirement in higher education service, an architecture based on MVC design pattern is presented. Some core technologies used in the platform system software, such as Struts Tiles and Struts Menu etc, are proposed in details by the end. Because of its struts-based fundamental architecture and running mechanism, the platform system software made a certain performance advantage and largely reduced the developing period. 相似文献
992.
Zhu Caicao Wang Hongen Gong JianxiaoYu Shixing 《保鲜与加工》1993,(6):51-57
In this paper,the mill stand and the rolled piece were studied as a system. Based on the disoreted masses and the deformation of bending curve of the roller and roll housing, according to Rayleigh method,the equivalent mass and and the equivalent stiffness of the mode were solved,and set up a multiple degree of freedom vibration dynamic model. And also did theoretical analysis and calculation with an exapmle of the 4200 thick plate rolling mills. 相似文献
993.
You lihua Wu Huibi Sun Renbo Wang Daivu 《保鲜与加工》1992,(4):48-53
The basic equations of wall plates of MAN' S dry gas holders are derived in this paper. According to the law of cylindrical bending given by the finite element results .we derive some approximate formula calculating the deflection and stresses of the wall plates from the basic equations. Compared with the known approximate calculating method.the method car. obviously increase the percision. 相似文献
994.
为探讨粮食增产、农民增收的有效途径,结合国家农业部在永修实施的"水稻综合生产能力科技提升试点行动"项目,选择推广7项节本增效综合配套技术,从而使项目核心区比非项目区增产12.8%,幅射区比非项目区增产5.8%,取得了较好的经济、社会和生态效益. 相似文献
995.
Using non-parameter test and multinomial logit regression, this paper studies the dividend policy and behavior empirically. The results show that the change of the earnings of firms affects their dividend policy. When the EPS of the firms increase, the probability of choosing not to pay cash dividend is maximal, yet when the EPS of the firms decrease, many firms choose not to pay cash dividend or choose to increase DPS, so that the information that the relevant firms have great expectation is transmitted to the market. Furthermore, this paper also finds that the successiveness of the dividend policy of the listed firms in China is not good. 相似文献
996.
应用免疫细胞化学方法对白血病抑制因子(leukemia inhibitory factor, LIF)、白血病抑制因子受体(leukemia inhibitory factor receptor, LIFR)和gp130在月经周期猕猴卵巢内的表达进行了研究。结果表明:LIF、LIFR和gp130在猕猴卵巢内的表达量随月经周期的不同而变化,LIF及其受体在增殖期卵巢内的表达量高于分泌期的卵巢。LIF及其受体在原始卵泡、腔前卵泡和有腔卵泡的卵细胞内表达量均较高,在颗粒细胞、卵泡膜、卵巢生殖上皮和卵巢基质中有少量表达,而在闭锁卵泡、退化的黄体和卵巢髓质中未见表达。LIF及其受体在猕猴卵巢内的表达可能受卵巢分泌的类固醇激素所调控,LIF可能通过自分泌或旁分泌的方式在猕猴卵泡发育及排卵等过程中起重要作用。 相似文献
997.
Zhao Changfu Feng Xiangui Li Yulan 《保鲜与加工》1991,(6):115-118
Calculations and analyses are made with the CVDA, IIW, JWES standards for the strength and welding defects of two spherical tanks of natural gas in CHONG QING. The results of the analyses indecate that though there are some problems with the welding quality in these tanks, they may still be used with the desingned presure. Now the formal working of these two spherical thanks has verified of the validity the calculations and analyses. 相似文献
998.
Wen Guangjun Xie Fuzhen Wang Ding 《保鲜与加工》1992,(1):134-138
The holographic three wavefront interferometer is used to measure large optical path difference. This method is proved to be practical through the measurement of the deformation -Voltage Curve of piezocrystal. 相似文献
999.
The relationship of investors and venture capitalists is an important part in venture capital. Based on asymmetric information, this paper analyzes the principal agent relationship between investors and venture capitalists with game theory. And this paper mainly discusses the choosing, controlling and incentive problem. It suggests that only the capable and self confident venture capitalists could accept the terms of the limited partnership. It also indicates that recompense mechanism which holds the interest of investors and that of venture capitalists tightly is the center of the limited partnership. Rate of yield is the key of recompense mechanism, it not only reflects the incentive on venture capitalists, also reflects the share of risk between investors and venture capitalists. At last, the market credit play an important role in venture capital. 相似文献
1000.
随着国内外农业发展及市场需求的变化 ,如何适应市场发展及加入 WTO的要求 ,是当前我国玉米育种工作者确定育种目标必须考虑的首要内容。1 国内外玉米育种趋势当今 ,国际上育种先进水平以美国、法国等国家为代表 ,其共同点是 :适应市场需要 ;抗病性、抗逆性好 ,符合农民要求 ;适合运输、包装加工、出口需要。为此 ,特别重视品质育种。具体地说是根据市场和用途 ,分别开展包括高油、高赖氨酸、高蛋氨酸、高苏氨酸、高蛋白、高硬粒型、高附加值等经济目标 ,以及低植酸、含有植酸酶玉米的环保型目标在内的玉米品质育种。如美国等选育的高赖… 相似文献