基于CART决策树的活跃读者群体预测模型研究

国家图书馆作为国家级公益性文化机构,拥有海量的馆藏资源和庞大的用户群体,多年来在资源建设、读者行为等方面积累了丰富的数据,基于这些重要数据进行科学预测非常有意义。从已有的读者信息和借阅数据中获取到与读者活跃度相关的所有特征,利用CART决策树构建了未来活跃读者群体的预测模型,并通过调参和剪枝等手段得到模型的最高得分。结果表明:读者ID、读者年龄、所借单册的分类号和出版社是影响读者活跃度的主要因子。该模型在5万条以上大样本数据量上呈现较好的预测能力,并通过交叉验证可以稳定模型的平均准确程度,避免了训练样本的随机性。

基于街景目标检测的城市人群活动研究——以武汉市汉正街为例

近年来,机器学习、计算机视觉等课题与其他学科之间的联动愈加频繁,在建筑学、城市空间的研究中起到跳板式的作用。本研究使用Mask-RCNN目标检测算法,对武汉市汉正街地区街景图像中的“板车工”人群进行图像分析与统计研究,统计全局街景图中检测到的目标数量,研究“板车工”人群活动特征及其面临的交通压力,以及反映出的城市空间使用问题。通过此类人群活动的数据化与可视化成果,提出指导城市设计中对于重点区域的选择,同时提出对用于城市研究的检测模型应当增加“人—物”的组合标签,以适用复杂的人群活动研究。

Effects of chemical modification on physicochemical properties and adsorption behavior of sludge-based activated carbon

This study aimed to explore the adsorption performance of sludge-based activated carbon(SBC)towards dissolved organic matters(DOMs)removal from sewage,and investigated the modification effect of different types of chemicals on the structure of synthesized SBC.Waste activated sludge(WAS)was used as a carbon source,and HCl,HNO 3,and Na OH were used as different types of chemicals to modify the SBC.With the aid of chemical activation,the modified SBC showed higher adsorption performances on DOMs removal with maximum adsorption of 29.05 mg/g and second-order constant(k)of 0.1367(L/mol/sec)due to the surface elution of ash and minerals by chemicals.The surface elemental composition of MSBC suggested that the content of C-C and C-O functional groups on the surface of modified sludge-based activated carbon(MSBC)played an important role on the adsorption capacities of MSBC towards DOMs removal in sewage.Additionally,the residual molecular weight of DOMs in sewage was investigated using a 3-dimension fluorescence excitationemission matrix(3 D-EEM)and high-performance size exclusion chromatography(HP-SEC).Results showed that the chemical modification significantly improved the adsorption capacity of MSBC on humic acids(HA)and aromatic proteins(APN),and both of Na OH-MSBC and HCl-MSBC were effective for a wide range of different AMW DOMs removal from sewage,while the HNO 3-MSBC exhibited poorly on AMW organics of 2,617 Da and 409 Da due to the reducing content of macropore.In brief,this study provides reference values for the impact of the chemicals of the activation stage before the SBCs application.

Phenotypic Characteristics and Function of NK Cell Subsets in cART-Treated HIV-1-Infected Individuals

Natural killer (NK) cell plays an important role in an innate immune response against viral infection. The kinetics regulation and functional consequences of NK cells in the pathogeneses of diseases are uncertain. We analyzed NK cell distribution and function of successfully combination antiretroviral therapy (cART)-treated HIV-1 infected individuals in Khon Kaen Regional Hospital, Thailand. The results demonstrated that increased percentage and the total number of NK cell in cART-treated HIV-1 infected patients with preferential high levels of CD56dimCD16+ and CD56-CD16+ subsets when compared with a control group even in undetectable viral load (<40 copies per milliliter). Concomitantly, decreased cytotoxic activity measured by CD107asurface expression with maintained IFN-γ production implied the impairment of cytolytic activity was not recovered after cART treatment. Thus, altered NK cell frequency and function by HIV-1 infection are not completely recovered with cART, which may contribute to impaired cellular immune response and persistence of HIV-1.

Control of Linear Servo Carts with Integral-Based Disturbance Rejection

This paper describes a system designed for linear servo cart systems that employs an integral-based Linear Active Disturbance Rejection Control(ILADRC)scheme to detect and respond to disturbances.The upgrade in this control technique provides extensive immunity to uncertainties,attenuation,internal disturbances,and external sources of noise.The fundamental technology base of LADRC is Extended State Observer(ESO).LADRC,when combined with Integral action,becomes a hybrid control technique,namely ILADRC.Setpoint tracking is based on Bode’s Ideal Transfer Function(BITF)in this proposed ILADRC technique.This proves to be a very robust and appropriate pole placement scheme.The proposed LSC system has experimented with the hybrid ILADRC technique plotted the results.From the results,it is evident that the proposed ILADRC scheme enhances the robustness of the LSC system with remarkable disturbance rejection.Furthermore,the results of a linear quadratic regulator(LQR)and ILADRC schemes are comparatively analyzed.This analysis deduced the improved performance of ILADRC over the LQR control scheme.

裂蹄木层孔菌总黄酮含量的测定及其抗氧化活性研究

利用体积浓度为70％的乙醇提取裂蹄木层孔菌中的黄酮类物质，以芦丁为对照品，利用紫外分光光度法测定裂蹄木层孔菌中的总黄酮含量，并研究了裂蹄木层孔菌中黄酮类化合物对 DPPH 自由基、超氧阴离子自由基、羟基自由基的清除作用．结果表明：在510 nm处，芦丁浓度在0．002～0．040 mg／mL范围内线性关系良好（r＝0．9985），裂蹄木层孔菌中总黄酮含量为38．2 mg／g；裂蹄木层孔菌中的黄酮类化合物对清除自由基有一定的作用，其清除效果在一定范围内随着总黄酮质量浓度的增加而增强．

大学生课外体育活动载体的创新实践与研究-以“艺体1＋1”工程为例

以大学生人文素质改革中的创新载体“艺体1＋1” 工程为例,阐述大学生课外体育活动的意义,运用调查法和 案例分析法对当前大学生课外体育锻炼活动载体创新进行可行性研究,从三个方面介绍“艺体1＋1”工程,一是重视力度之 大：课外体育活动赋予学分;二是顶层设计之精： “艺体1＋1”工程之为何物;三是实施方案之详： “艺体1＋1”工程的组织实施; 最后以实证和问卷调查的方法,介绍体育文化之显： “更快、更高、更强” 的奥林匹克精神和“运动、健康、发展”的特色体 育精神.本文为高校如何将校园体育文化建设与人文素质教育相融合提供借鉴和建议.

污泥活性炭对活性黑KN-B染料的脱色研究

利用城市污水厂二沉池污泥为原料,以0.5mol/LKOH为活化剂,与湿污泥混合直接活化,干化后在600℃条件下,采用水蒸气为活化气和保护气,炭化60min,制得性能良好的污泥活性炭:孔容积为0.19cm3/g,比表面积为737.61m2/g,碘值为879.62mg/g。并进一步将污泥质活性炭应用于活性黑KN-B模拟染料废水的处理,考察了吸附时间、活性炭投加量和pH值等对色度脱除效果的影响,实验结果表明,20℃温度条件下,初始浓度为500mg/L,污泥活性炭的最佳投加量为8mg/L,吸附时间为30min,色度脱除率可达95.7%。