176 research outputs found

    试论流转税税率的设计——贴近消费原则

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    既然我国流转税制改革目标是建立以增值税普遍调节和以消费税特殊调节相结合的新型流转税税制,那么如何进行流转税税率的设计,是一个急需解决的重要问题,在理论上和实践上都具有重大的意义。本文试就这个问题,根据社会主义市场经济体制的要求,谈一点粗浅的看法。由于我国长期以来强调运用流转税差别税率的调节作用,调整税率时又一贯坚持保持原税负的原则,所以,我国流转税税率档次多,具体分布如下:产品税有21档,税率从3%到60%;增值税共12档,从8%到45%;营业税有4档,从3%到15%

    MySQL密码认证算法的FPGA优化实现

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    My SQL数据库软件被广泛地应用于WEB项目中,因此它的安全性极为重要。本文针对My SQL密码认证算法的FPGA实现以及应用进行研究,利用并行化、流水线架构实现My SQL认证算法。提出一种基于BRAM的SHA-1算法流水线架构并对其流水线级数进行优化,从而实现高性能。同时利用多模块并行,多密码验证算法,以提高硬件运行速度和计算资源的利用效率。通过优化,高性能实现了基于FPGA硬件的My SQL认证算法,单块芯片的口令恢复速度为18亿个口令密码每秒,多个FPGA构成子板的认证速度为72亿/秒,比采用GPU GTX 690平台的速度提高了5倍。本研究项目获得集成电路设计与测试分析福建省高校重点实验室建设资金.厦门市科技局科技专项经费以及2017年厦门大学教学改革研究项目资金的支持

    Photosynthetic capacity of three common species of macroalgae and the application in coral aquarium

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    利用水下饱和脉冲调制叶绿素荧光仪(dIVIng-PAM)测定了珊瑚养殖水处理中3种常见大型海藻石莼(ulVA lACTuCA)、条浒苔(EnTErOMOrPHA ClATHrATA)和羽状蕨藻(CAulErPA MEXICAnA)光能转化效率(fV/fM),快速光曲线(rlC)相关参数和非光化学淬灭(nPQ)。结果表明:石莼和条浒苔的fV/fM分别为0.808±0.004和0.816±0.009,显著高于羽状蕨藻。最大相对电子传递速率rETrMAX(17.52±2.92和19.59±4.43μMOl E·M-2·S-1)、半饱和光强Ik(53.41±8.18和59.71±13.52μMOl PHOTOnS·M-2·S-1)也明显高于羽状蕨藻(rETrMAX和Ik分别为13.72±5.41μMOl E·M-2·S-1和32.67±14.06μMOl PHOTOnS·M-2·S-1),表明石莼和条浒苔有着比羽状蕨藻更高的光合能力和对强光的耐受能力,光保护能力更强;羽状蕨藻较高的rlC初始斜率α表明其在弱光下拥有更强的光捕获能力,弱光下光合效率更高;随光照的增强(0~373μMOl PHOTOnS·M-2·S-1),羽状蕨藻nPQ的增幅有限(0~0.2),最大值仅为条浒苔和石莼的38.1%和62.5%,表明这种藻类更容易受到强光的抑制。因此,在珊瑚养殖的水处理中,可以根据不同的光照选择适宜的藻种或藻种组合并根据光梯度进行布局,反之也可以根据藻种来选择合适的光源,以达到最佳的处理效率。This study investigated the difference of photosynthetic capacity in three macroalgae species( Ulva lactuca,Enteromorpha clathrata,and Caulerpa mexicana) commonly used for nutrient removal in coral aquariums.The photochemical efficiency( Fv/Fm),parameters relevant to rapid light curve( RLC) and non-photochemical quenching( NPQ) in the macroalgae were measured by underwater saturation pulse modulated chlorophyll fluorometer( Diving-PAM).The results showed that Fv/Fmwas 0.808 ± 0.004 for U.lactuca and 0.816 ± 0.009 for E.clathrata,which were higher than that for C.mexicana.Higher maximum relative electron transfer rates( rETRmax)( 17.52 ±2.92 and 19.59 ±4.43 μmol e·m- 2·s- 1) and half-starved value of light intensities( Ik)( 53.41 ±8.18 and 59.71 ±13.52 μmol photons·m- 2·s- 1) were observed in U.lactuca and E.clathrata than that in C.mexicana( 13.72 ± 5.41 μmol e·m- 2·s- 1for rETRmaxand 32.67 ± 14.06 μmol photons·m- 2·s- 1for Ik),indicating that U.lactuca and E.clathrata have stronger photosynthetic capacities,photo-protection capacities and tolerance to higher intense light than C.mexicana.A significantly lower RLC initial slope α in C.mexicana implied that this algal species has a higher photosynthetic capacity under weak light condition.With increasing the light intensity( 0- 373 μmol photons·m- 2·s- 1),however,C.mexicana had a limited increase of NPQ( 0- 0.2),the maximum of which was equivalent to 38.1% of that in U.lactuca and 62.5% of that in E.clathrata.These results indicate that the photosynthesis of E.clathrata may be more easily limited by intense light.Our study suggests that the selection of algal species for nutrient removal in a coral aquarium should be adapted to the light intensity.Single species or the combination of different species of macroalgae can be selected according to the illumination of the coral aquarium in order to maximize the efficiency of nutrient removal.国家海洋局第三海洋研究所基本科研业务项目(海三科2011033); 厦门海洋研究开发院共建项目; 海洋公益性行业科研项目(201105012)资

    LED Color Analysis

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    主要对蓝光、绿光、白光lEd的色度特性进行分析,首先通过单色仪,分别测得蓝光、绿光、白光lEd的相对光谱功率分布并以色度学理论为基础,计算出光源主波长、色纯度、色温和显色指数.计算结果表明:蓝光lEd和绿光lEd主波长随标准光源的不同变化不大,色纯度比较高,分别在0.64和0.87左右,一般显色指数为-29和-14,显色性很差,不适合用来做照明光源.白光lEd主波长随标准光源的不同变化较大,色纯度相当低,接近0,一般显色指数为82,显色性很好,完全符合照明光源的要求.In order to study the color characteristics of light-emitting diode,the characteristics of blue,green and white LED colors are analyzed.Firstly,the spectral power distribution of blue,green,white LED is respectively measured by using the monochromator,and then on the basis of the theory chroma,the main light source wavelength,color purity,color temperature and color rendering index are calculated.The results show that blue LED and green LED dominant wavelengths change little with different standard light sources,and the color purities are relatively high,at 0.64 and 0.87,respectively,the general color-rendering is very poor for the index of-29 and-14,so these blue and green LED are not suitable to be used as lighting source.White LED dominant wavelength largely change with different standard light sources,and color purity is relatively low,near 0,color rendering is good for the general color-rendering index of 82, so white LED is in full conformance with the lighting requirements

    Studies on the infection of freshwater crabs by Paragonimus metacercariae in Yunxiao county, Fujian

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    目的调查云霄县淡水蟹种类及其感染并殖吸虫囊蚴的情况。方法选取不同地理方位为调查点,捕捉各调查点的淡水溪蟹进行分类和并殖吸虫囊蚴的检查。结果全县共调查6个乡(镇)20个村,共捕捉230只蟹,查出漳州华溪蟹(n=136)、漳浦束腰蟹(n=63)和闽溪蟹(待定种)(n=31)3种;检出感染并殖吸虫蟹15只,阳性检出率为6.6%(15/230),蟹的感染指数为0.11,对福建华溪蟹和中华束腰蟹种类及分布作了修正。结论云霄县并殖吸虫宿主淡水溪蟹有3种,蟹感染并殖吸虫呈下降趋势,但仍为中度并殖吸虫疫源地。Objective To study the distribution of freshwater crabs and their infection by Paragonimus in Yunxiao county, Fujian.Methods Freshwater crabs were collected and identified.The crabs were then dissected and examined for the presence of Paragonimus metacercariae.Results Six tons of crabs from 20 villages (Yunxiao county) were collected.Three species of crabs were found , namely Sinopotamon zhangzhouense, Somanniathelphusa zhangpuensis and Minpotamon spp.The infection rate was 6.6% (15/230) for the Paragonimus, and the index of crab infection was 0.11.Species of freshwater crabs and its geographic distribution were revised for Sinopotamon fukienense and Somanniathelphusa sinensis.Conclusion Freshwater crabs are the intermediate hosts of Paragonimus in the Yunxiao county.科技部自然资源平台项目(2005DKA21104

    福建省和溪南亚热带雨林下木层植物的滴水叶尖和滴水大小

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    研究福建省南靖县和溪南亚热带雨林下木层植物滴水叶尖的发育情况以及滴水大小.该森林滴水叶尖发育程度中等,离叶尖端3mm处的叶宽平均为2.37mm,粗叶木的最小,为0.95mm,瓜馥木的最大,为4.95mm.水滴大小平均为0.044g,日本五月茶的最小,平均为0.023g,瓜馥木的最大,平均为0.078g.水滴大小与滴水叶尖宽度存在极显著的正相关(p<0.001),滴水叶尖越发达,下落的水滴越小.滴水叶尖的作用首先是迅速、有效地排除叶面上的积水,此外可能与对土壤类型的适应有一定的关系

    Development of a pedestrian navigation system that presents the optimum route information for mobility constraint people.

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    We developed a pedestrian navigation system that presents the optimum route information according to the degree of disablement for handicapped or aged people. The system displays information for town walking with ptimum route on the Google Map or by the direction indication on the AR camera window. Based on the system, we developed a mobile application system, named the\u27SAKAI old town map\u27, for sightseeing and walking around the historical area in Sakai·shi, Osaka. As an evaluation experiment, subjects with wheelchairs moved around the area using the system and we analyzed their behavior and introspection. The results showed that our pedestrian navigation system would be effective to support the daily life of move constraint people.平成26年度関西大学研究拠点形成支援経費:研究課題「利用者別最適経路を選択可能なナビゲ ーションシステムの研究開発と実装地域における社会的変化の研究

    对价支付影响因素的理论和实证分析

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    我国上市公司股权分置改革成功与否关系我国证券市场未来的发展。本文根据财务理论,结合国情构建6个研究假设,并以330家实施股权分置改革的上市公司为样本,应用实证研究方法,探讨非流通股东的对价送出率及流通股东的对价送达率的影响因素。研究发现股改工作中所采用的市场化博弈机制可在一定程度上保障对价方案的合理性和两类股东的利益,但仍存在诸如机构投资者未发挥议价能力等问题
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