70 research outputs found

    机器意识最新进展的哲学反思

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    机器意识研究在近十年取得了瞩目的成就,尤其在脑智功能技术实现方面取得了长足的进步,但相应地,其在意识觉知机制方面却依然没有起色。本文分析了机器意识研究在可行性、判定标准和解释上所遭遇到的困难,并指出了出路所在。国家自然科学基金项目“针对涉身行为的自我意识机器人构建方法及其实现”(项目编号:61273338

    嵌入式系统和红外图像的火焰检测算法

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    火焰的检测与识别是对火灾预防与控制的重要因素,目前已设计出一种嵌入式的图像采集系统,对嵌入式系统的概念进行了分析,分别探讨了火焰目标的提取、火焰特征的识别、火焰动态特征的识别以及火焰检测算法的设计,通过嵌入式系统以及红外图像的综合技术的实验分析,体现出该技术进行火焰检测算法的优势

    The Market Risk Management of Securities Companies in China:A Research Based on VaR

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    市场风险是证券公司面临的主要风险之一,对市场风险的管理是证券公司风险管理中最重要的工作。从我国的实际来看,一方面,我国证券市场波动频繁,投机氛围比较浓厚,市场风险较为复杂多变,另一方面,中国证券公司发展历程短,风险意识较为淡薄,市场风险管理水平还有待提高。研究证券公司市场风险管理问题,对于我国证券公司提高管理水平、增强竞争力有很大意义,也有助于保护投资者,促进中国证券市场健康、快速发展。 本文首先梳理了市场风险管理主要理论的发展脉络,对国内外近期相关研究成果进行综述。接着分析中国证券公司市场风险管理现状,指出中国证券公司目前在市场风险管理上存在的主要问题。然后本文针对中国证券公司市场风险管理...Market risk is one of the main risks the securities companies face, the management of market risk is the most important part in the risk management for securities companies. To our country, on the one hand, the securities market’s volatility is often more serious, market risk is more complex and changeable, on the other hand, the history of securities companies in China is very short, their risk a...学位:经济学硕士院系专业:经济学院经济系_西方经济学学号:1532010115203

    Design and Field Analysis of PMMA Rib Optical Waveguides

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    利用有效折射率法(E IM)理论设计了有机聚合物脊形光波导结构,并分析光波导中传输的模式场,确定出光波导结构的适宜尺寸范围。光波导结构中分别选用PMMA(聚甲基丙烯酸甲酯)与PDM S(聚二甲基硅氧烷)作为波导层与包层的材料,用光漂白法来实现脊形波导结构。首先利用E IM法分析脊形波导区的宽度与高度之间的关系对归一化色散曲线的影响,以及波导层与包层的折射率匹配的影响,然后又通过分析波导区传输的基模场来讨论传输的损耗问题。研究发现波导结构的脊宽与脊高之比w/d越大,其有效折射率neff越大,而此结构尺寸又需约束在一定范围内,否则将造成很大的传输损耗。The structure of the polymer rib optical waveguide is designed by using effective index method(EIM),and the mode field distribution in these waveguides is analyzed to determine the suitable structural size range.For this rib waveguide realized by photo-induced bleaching,two kinds of polymer materials,PMMA and PDMS,are chosen as the core layer and the cladding layer respectively.Firstly with EIM,the influence of the relationship between the rib width w and height d on the normalized dispersion curve and the effect of refractive index matching are studied.Then,the base mode field in the waveguide is analyzed to discuss the transmission loss.It has been found that the larger the size ratio w/d of the PMMA rib waveguide is,the greater its effective index n_(eff)becomes.But this structure size should be limited in certain range,otherwise very large transmission loss would result.高校骨干教师项目资金;; 福建省青年科技人才创新项目资金(2001J024

    Genetic Algorithm and Its Implementation of Automatic Generation of Chinese SONGCI

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    主要针对宋词这种特殊的汉语诗歌体裁,开展了有关自动生成算法及其实现方法的探索性研究.研究工作主要根据宋词特点,设计了基于平仄的编码方式、基于句法和语义加权值的适应度函数、基于精英主义和轮盘赌算法的选择策略,采用部分映射和启发式交叉算子和启发式变异算子,从而构建了一种基于遗传算法的宋词生成计算模型并进行了系统实现.实验结果表明,所建立的计算模型及其软件系统,初步实现了机器自动生成宋词的目标,对于给定的主题词和词牌,基本上能够自动生成有一定欣赏价值的宋词.论文的工作也填补了我国在汉语诗歌自动生成研究方面的不足.Automatic generation of poetry has always been considered a hard nut in natural language generation.This paper reports some pioneering research on a possible generic algorithm and its automatic generation of SONGCI.In light of the characteristics of Chinese ancient poetry,this paper designed the level and oblique tones-based coding method,the syntactic and semantic weighted function of fitness,the elitism and roulette-combined selection operator,and the partially mapped crossover operator and the heuristic mutation operator.As shown by tests,the system constructed on the basis of the computing model designed in this paper is basically capable of generating Chinese SONGCI with some aesthetic merit.This work represents progress in the field of Chinese poetry automatic generation.国家自然科学基金No.60975076---

    纳米颗粒对极化聚合物的非线性驰豫特性的影响研究

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    以K-M模型和光散射理论为基础,建立了纳米颗粒掺杂改性的PMMA聚合物材料的紫外散射模型,推导出了考虑入射波偏振的理论计算公式,解决了在非线性光学性能的抗老化与聚合物波导的加工之间所存在的矛盾。利用MATLAB编制了基于Mie算法的程序,分析了收敛条件,并对体系纳米粒子的粒径与后向散射系数、吸收系数的定量关系进行理论计算。仿真结果表明,在波长约200-400nm范围内,最佳抗老化效果的粒径集中在20-50nm之间。利用偏振对于粒子散射影响较大的特点,提出用带偏振片的紫外灯来进行波导光刻加工的设想,确定了最佳掺杂颗粒半径35-40nm之间的理想范围。最后,将仿真结果与实验结果进行了对比分析,证实了散射模型和仿真过程的可靠性。“福建省科技计划重点项目(2007H0036)”提供资

    Establishment of MDCK cell lines which stably express visualable human neonatal Fc receptor

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    [目的]建立稳定表达融合EGFP的人新生儿Fc受体(h FcRn)的MDCK细胞株。[方法]构建重组慢病毒质粒p EGFP-h FcRn,采用四质粒包装系统共转染HEK 293T细胞生产重组慢病毒,感染MDCK细胞后对EGFP阳性细胞进行流式单细胞分选;通过Western Blot及EGFP-β2m荧光共定位验证h FcRn的完整性,并用流式细胞仪检测h FcRn与人Ig G的结合活性。[结果]测序结果表明成功构建p EGFP-FcRn慢病毒表达载体;感染后EGFP阳性MDCK细胞比例约为26.5%,流式单细胞分选后得到纯阳性细胞;荧光共定位及Western Blot均检测到h FcRn的完整表达;流式分析表明细胞株上的h FcRn与Ig G存在p H依赖性结合。[结论]成功获得稳定表达具有生物活性的可视化h FcRn的MDCK细胞株。[ Objective] To establish MDCK cell line stably expressing EGFP- human neonatal Fc receptor(hFcRn) fusion protein. [ Methods ] The lentiviral expression vector for EGFP - hFcRn fusion protein was constructed. Generating by co - transfection of four -plasmids into HEK 293T cells ,the lentivirus particles were used to infect MDCK cell line. EGFP positive single cell was obtained by FACS, and then FcRn expression was identified by fluorescence co -location with EGFP - β2m and confirmed by Western Blot. Flow cytometry was used to detect binding activity of hFcRn and human IgG. [ Results ] DNA se- quencing demonstrated that the lentivirus vector pEGFP - FcRn was constructed successfully. The percentage of EGFP - posi- tive ceils was about 26.5% after infection. Expression of the complete protein was detected through fluorescence co - location and Western Blot, respectively. Flow cytometry analysis showed that the cell lines could pH - dependently capture human IgG. [ Conclusion] MDCK cell line stably expressing functional visualable hFcRn was established.基金项目:国家自然科学基金项目(“结构生物学指导的HBV治疗性抗体人源化及其关键技术研究”,No.31600748;“抗呼吸道合胞病毒高中和活性抗体的保护机制研究”,No.81401668;“基于广谱中和单抗的通用型流感疫苗设计及其结构基础研究”,No.31670934

    不同保水固沙措施对沙培番茄生长和基质环境的影响

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    针对我国荒漠化危害严重,不利于植物种植等系列问题,以番茄为试验材料,结合纸膜、保水剂、生物基固沙剂等不同保水固沙措施,分析各处理下基质的理化性质以及番茄的生物学性状,以探明各处理对沙地环境的改善效果及对番茄生长的影响,为沙漠的防治及沙产业的发展提供参考。结果表明:瓦楞纸处理显著提高了番茄果实的有机酸、可溶性糖含量,分别比CK高27. 78%、8. 87%,其pH值比CK高0. 89,速效氮含量是CK的40倍;牛皮纸处理20~40 cm含水量比CK高73. 40%;保水剂处理可明显促进根系的生长发育,其根长、根直径以及体积分别比CK高16. 25%、29. 17%、56. 58%,番茄可溶性固形物含量比CK高7. 17%,沙子的比重和总孔隙度分别比CK高12. 88%、38. 35%,但容重比CK低6. 88%;生物基B处理可明显提高果实内可溶性糖含量,比CK高15. 53%,可显著提高沙子中的速效钾含量,比CK高55. 99%,有机质含量比CK高10. 91%;生物基A处理对番茄的株高有明显的促进作用,比CK高19. 81%,叶绿素含量比CK高8. 24%,番茄根系的总长比CK高45. 95%,叶片净光合速率是CK的1. 66倍,蒸腾速率以及气孔导度都相对较高,果实内可溶性固形物以及可溶性糖的含量分别比CK高6. 33%、8. 87%,容重比CK高3. 33%,速效氮含量是CK的16倍。通过主成分分析,生物基A的综合得分最高。因此,生物基A处理对促进番茄生长发育以及改善沙地生态环境效果最显著。宁夏回族自治区“十三五”重大研发项目(2016BZ0902);;“十二五”国家科技支撑计划项目(2014BAD05B02);;吴忠国家园区专项(2016BN05);;宁夏回族自治区科技创新领军人才项目(KJT2017001

    STUDY ON ADSORPTION OF A BACILLUS STRAIN TO CADMIUM AND COPPER

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    从土壤中分离并纯化获得1株芽孢杆菌(Bacillus)。通过该菌菌液对Cd2+和Cu2+的吸附实验,探讨了该菌株对上述2种重金属离子的吸附特性。结果表明:该菌株对2种重金属离子都有较强的吸附能力,但对Cu2+的吸附能力比对Cd2+强;其吸附行为可以用Langmu ir和Freund lich吸附方程描述,但更符合Freund lich吸附方程。与此同时,研究还考察了吸附条件的影响,并获得了最佳的吸附实验条件。A bacteria strain was separated and purified from the soil and identified as Bacillus.In an adsorption experiment,its biosorption characteristics to Cd~(2+) and Cu~(2+) were studied.The strain was shown to have a strong adsorptive capacity to the above two metal ions,with a stronger adsorptive capacity to copper ions than to cadmium ions.Its adsorption behavior could be described by either the Langmuir adsorption equation or the Freundlich adsorption equation,the latter equation being the better.The effect of experimental conditions on adsorption was examined and the optimum experimental conditions were identified
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