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Search Results: 1 - 10 of 65758 matches for " 梅瑞婷 "
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信用卡违约预测模型分析以及影响因素探究
Study on Analysis and Influence Factors of Credit Card Default Prediction Model
 [PDF]

, 徐扬, 王国长
Statistics and Applications (SA) , 2016, DOI: 10.12677/SA.2016.53026
Abstract: 信用卡对于银行来说是高收益和高风险并存的业务,伴随信用卡业务发展的是各大银行都在利用网络和移动端的数据来建立客户的信用评分系统。如何从客户所填的资料里对客户进行信用评估、如何鉴别所填资料的真假性及应该要求客户填什么类型的资料等对银行来说是至关重要的。本文基于2005年台湾信用卡客户数据,建立Lasso-Logistic及随机森林模型来探索影响客户信用的关键因素,包括个体特征及某些客观特征,通过比较模型的预测准确度以及F得分等指标来选择预测效果更优的模型对银行信用卡违约进行预测分析。信用卡违约预测模型的建立以及影响客户信用的关键因素的探索,对于银行选择客户和设计资料填写具有重要的指导价值,并且能够为信贷决策提供一定的理论支持,具有很强的理论和现实意义。
Credit cards are a bank business in which high income and heavy risk coexist. Along with the de-velopment of the credit card business, banks are using the Internet and mobile data to establish customer credit rating system. How to evaluate customer credit from the information that cus-tomers fill in, and how to identify the information true or false, and what type of information that customers are asked to fill are crucial for banks. Based on the credit card customer data of 2005 in Taiwan, this article established Lasso-Logistic model and random forest model to explore the key factors which effect customer credit, including individual characteristics and some objective cha-racteristics. Through comparing the prediction accuracy of the model and F score index, we selected the model of better prediction effect to forecast the bank credit card defaults. The establishment of the credit card default prediction model and the exploration of the key factors influencing the customer credit not only have a important guidance value for banks to choose customers and design data, but also can provide certain theoretical support for the credit decisions. In addition, it has a strong theoretical and practical significance.
基于LASSO-SVM模型的银行定期存款电话营销预测
Telephone Marketing Forecast of Bank Time Deposits Based on the LASSO-SVM Model
 [PDF]

, 徐扬, 王国长
Statistics and Applications (SA) , 2016, DOI: 10.12677/SA.2016.53029
Abstract: 定期存款一直以来都是银行的主要资金来源,而电话营销也成为一种低成本,广受银行欢迎的营销模式。因此,如何提高电话营销成功率成为银行急需解决的重要问题。其中,影响客户订购定期存款的因素复杂多样,而这些因素之间可能存在多重共线性,如果银行不加选择地引入众多影响因素来进行订购定期存款的预测,往往不能取得良好的预测效果,甚至产生错误的决策。在统计学习方法中,LASSO方法可以同时进行参数估计和变量选择,所以本文提出了基于LASSO与支持向量机的组合预测方法。同时,与SVM、神经网络、LASSO-神经网络方法的预测效果进行比较,验证了LASSO-支持向量机组合预测方法的拟合预测效果要优于另外三种预测方法。
Time deposits have always been the main source of funds for the bank, and the telephone mar-keting has become a low-cost marketing model, which is widely popular with the bank. Therefore, how to improve the success rate of telemarketing has become an important problem to solve. Among them, the factors that affect customers ordering deposits are complicated, which may have multicollinearity. If banks indiscriminately use many influence factors to predict deposits, they often cannot obtain good prediction effects, and even make the wrong decision. In the statistical learning methods, the LASSO method can be used to estimate parameters and select variables, so this paper presents a combination forecast method based on the LASSO and Support Vector Ma-chine (SVM). At the same time, compared with SVM, neural network, LASSO-neural network me-thods, we find that the effect of LASSO-SVM forecasting method is better than the other three kinds of forecasting methods.?
科技期刊审稿费与稿费的收发情况调查及分析
单政?,马豪?,芹?,尹春,路淑
中国科技期刊研究 , 2014,
Abstract: 基于2011年版《中文核心期刊要目总览》中刊录的248本医药、卫生类核心期刊进行调查,对我国科技期刊的审稿费收取情况及数额、稿费发放情况等进行调查和统计。结果表明213本获得数据的期刊中不收取审稿费42本(19.72%)、不录用不收取审稿费5本(2.35%)和收取审稿费166本(77.93%);200本获得数据的期刊中有稿费、发放稿费的180本(90.0%),有稿费、但不发放强制将其作为购刊款或折抵版面费的3本(1.5%),不支付稿费7本(8.5%)。笔者支持编辑部实行在作者投稿时适当收取审稿费的制度,认为此做法除了能在经济角度对编辑部办刊经费进行适当补充外,对于防止因一稿多投和恶意投稿的现象所产生的各种弊端也有一定作用,但也应注意维护作者相关权益。关于稿酬,笔者认为编辑部应严格执行国家著作权法有关规定,坚决杜绝苛扣和挪用现象的发生。
医学生主观幸福感的发展状况及影响因素
Developmental Characteristics and Influence Factors of the Subjective Well-Being of Medical College Students
 [PDF]

侯永, 张伊
Advances in Psychology (AP) , 2014, DOI: 10.12677/AP.2014.46109
Abstract:
目的:探讨医学本科生主观幸福感的发展特点及其影响因素。方法:在广东省内随机抽取426名本科生,采用主观幸福感量表、大五人格量表和罗特的内在–外在心理控制源量表对他们进行测试。结果:人口学变量中的专业和经济状况、大五人格中的外倾性、神经质、开放性等三个维度和心理控制源总分对主观幸福感具有预测作用。专业前景好、经济状况好、内控的归因、高外倾性、高开放性和低神经质的个体主观幸福感较高。结论:医学本科生的主观幸福感是一个多维的、复杂的心理现象,各个影响因素的作用机制有待进一步。
Objective: To find out the developmental characteristics and influencing factors of subjective well- being in medical college. Methods: A total of 426 medical college students who were sampled ran-domly from Guangdong were assessed with satisfaction with life scale and positive affect and neg-ative affect scale. The data showed that: 1) profession and personal family economic income can influence SWB; 2) locus of control influences SWB; 3) the 3 dimensions of E (extraversion), N (neuroticism) and O (openness to experience) in the big five-factor model of personality are im-portant influenced factors of SWB.
利用基因枪轰击花药将GUS基因导入大麦小孢子
杜志钊,高润红,陈志伟,,李梁,郭桂,,黄剑华
麦类作物学报 , 2011, DOI: 10.7606/j.issn.1009-1041.2011.06.005
Abstract: 为了建立和不断完善大麦单倍体细胞遗传转化体系,并突破其对模式品种的依赖,以2份大面积推广种植的优良大麦品种的花药为受体材料,利用基因枪法将GUS报告基因导入其小孢子,比较了不同基因型大麦花药经基因枪轰击后小孢子转化频率的差异,并探讨了不同轰击次数对小孢子转化频率的影响。研究结果表明,供试品种花药经基因枪轰击后,都有少量小孢子被成功转化,表现GUS活性;玉米泛素基因Ubi启动子能启动报告基因GUS在大麦小孢子中表达;基因枪轰击对小孢子的转化频率存在一定的基因型差异,两轰击处理组合下,品种“花22”的小孢子转化频率比“花30”的分别高出50.9%和77.8%;具有GUS活性的小孢子随轰击次数的增多而增加,轰击2枪较轰击1枪小孢子转化频率高出113.9%(花30)和77.6%(花22)。
优良大麦品种花30幼胚遗传转化体系的优化
高润红,杜志钊,郭桂,邹 磊,,陈志伟,李 梁,,黄剑华
植物遗传资源学报 , 2012,
Abstract: 以大麦花培基因型“花30”的幼胚为外植体,设置不同的培养基类型、不同激素配比及碳源,研究其对幼胚愈伤组织诱导及绿苗分化的影响,以此建立和优化一个适于优良大麦品种遗传转化的高效组织培养体系。结果表明:在N6、MS和B5的组合改良培养基下,以蔗糖为碳源,附加2mg/L2,4-D,1mg/LABA时,有最高的愈伤组织诱导率,且愈伤质量最好。Cu2+的添加具有抑制幼胚直接发芽成苗和改善愈伤组织质量的双重功效。添加2mg/L6-BA对愈伤组织的分化效果比较理想。为了提高农杆菌介导转化大麦外源基因的瞬时表达率和优化遗传转化体系,利用“花30”幼胚产生的愈伤组织为受体材料,通过检测GUS基因的瞬时表达情况,研究了农杆菌介导的大麦遗传转化中菌液的浓度,侵染时间以及共培养天数对遗传转化的影响,结果表明:当菌液浓度OD600=0.5的条件下,侵染15min,共培养2d表现出最佳的GUS瞬时表达率。
大麦单粒种子起源的小孢子培养再生频率研究
郭桂,,,刘成洪,高润红,徐红卫,李颖波,黄剑华,王亦菲,
- , 2019, DOI: 10.7606/j.issn.1009-1041.2019.02.05
Abstract: 为提高单株小孢子培养的再生效率,以大麦品种花30为材料,在人工气候室研究了离体穗、离体小花预处理时间和诱导培养基中机氮、有机氮含量以及添加PEG对愈伤组织产量、绿苗产量和再生能力的影响。结果表明,离体穗5 ℃处理19 d的愈伤组织和绿苗产量及再生能力均优于32 d的,离体小花预处理1~2 d可促进愈伤组织的形成和绿苗的分化;降低机氮浓度[KNO3降至707.5 mg·L-1,(NH4)2SO4降至115.75 mg·L-1]可提高愈伤组织和绿苗产量及再生能力;提高有机氮浓度(谷氨酰胺从400 mg·L-1提高到1 600 mg·L-1,水解酪蛋白从100 mg·L-1提高到400 mg·L-1)可增加小孢子愈伤组织和绿苗产量;培养基中添加4% PEG可提高小孢子愈伤组织产量和质量。
社区 Homebound 老人发生现状及特征分析
Prevalence and characteristic of homebound older adult in community

汪凤兰,张小丽,邢凤,,吴庆文,景丽伟,张盼,
- , 2015,
Abstract: 摘要:目的 了解社区老人 homebound(居家不出)状态的发生情况及其发生特征。方法 采用随机整群抽样调查的方法,在蚌埠市龙子湖区所辖的社区中随机抽取1个社区,对社区内符合条件的60岁及以上的老年人,采用统一的调查量表进行面对面调查收集资料。结果 社区老年人群居家不出阳性率为14.8%。多因素Logistic回归分析显示走路不平稳(OR=4.066)、脑卒中(OR=3.369)、抑郁(OR=2.244)、关节炎(OR=1.971)、邻居交往(OR=1.710)、年龄(OR=1.060)、BMI≤18.5(OR=0.278)是居家不出发生的危险因素。结论 居家不出在社区老年人群中阳性率较高,建议采取相关针对性措施预防和控制居家不出的发生。
基于Y染色体ZFY-10标记多态性探究柴达木黄牛父系支系组成和起源
Explore the patrilineal branches and origin of Qaidam cattle based on the polymorphism of Y chromosome ZFY-10 marker

马志杰,夏小,陈生,,张俸伟,晁生玉,雷初朝
- , 2018,
Abstract: 为从分子水平上揭示柴达木黄牛的父系遗传结构组成、遗传多样性水平及父系遗传背景,通过PCR方法和直接测序技术,以8头大别山牛(瘤牛)公牛为试验对照,对106头柴达木黄牛公牛Y染色体ZFY-10标记进行多态性检测分析。结果表明:1)通过ZFY-10标记上变异位点的联合定型分析,可以准确地检测普通牛Y1和Y2单倍型组及瘤牛Y3单倍型组;2)柴达木黄牛在ZFY-10标记上存在GT核苷酸插入/缺失多态性,依据该标记多态位点确定单倍型组,表明柴达木黄牛包含Y1和Y2两种普通牛单倍型组,所占频率分别为0.217和0.783。在柴达木黄牛品种内,大柴旦、乌兰、格尔木、茫崖和都兰5个群体Y2单倍型组的频率依次为1.000、0.933、0.907、0.650和0.522,而Y1单倍型组频率依次为0、0.067、0.093、0.350和0.478,表明茫崖和都兰2个群体具有较高的Y1单倍型组比例;3)柴达木黄牛总的单倍型多样度为0.343 0±0.045 6。在柴达木黄牛品种内,大柴旦、乌兰、格尔木、茫崖和都兰5个群体的单倍型多样度分别为0、0.133 3、0.172 8、0.478 9和0.521 7,表明都兰和茫崖2个群体相比其他3个群体具有较高的父系遗传多样性。综上所述,Y染色体ZFY-10标记变异位点的联合定型分析可以确定和推断黄牛的父系支系组成和起源;柴达木黄牛含有Y1和Y2两个普通牛父系支系,具有2个普通牛父系起源,父系遗传多样性较低,品种内茫崖和都兰2个群体遗传变异相对丰富。
To explore the paternal genetic structure of Qaidam cattle (Bos taurus), the genetic diversity and background were investigated at molecular level.By using 8 male Dabieshan zebu as experimental control, the polymorphism of Y chromosome ZFY-10 marker in 106 Qaidam cattle was analyzed based on PCR amplification and direct sequencing.The results showed that:1) The variations identified by ZFY-10 marker could be used to distinguish Bos taurus haplogroup Y1 and Y2, and Bos indicus haplogroup Y3;2) The polymorphism of GT insert/deletion on ZFY-10 marker indicated that Qaidam cattle owned Y1 and Y2 taurine haplogroups with frequencies of 0.217 and 0.783, respectively.In Qaidam cattle breed, the frequencies of haplogroup Y2 in populations of Dachaidan, Wulan, Golmud, Mangya and Dulan were 1.000, 0.933, 0.907, 0.650 and 0.522 respectively, while the frequencies of haplogroup Y1 were 0, 0.067, 0.093, 0.350 and 0.478 respectively, indicating that the populations of Mangya and Dulan had a higher proportion of Y1 haplogroup;3) The total haplotype diversity of Qaidam cattle was 0.343 0±0.045 6.In Qaidam cattle breed, the haplotype diversities in populations of Dachaidan, Wulan, Golmud, Mangya and Dulan were 0, 0.133 3, 0.172 8, 0.478 9 and 0.521 7, respectively.In conclusion, variations on Y chromosome ZFY-10 marker could be used to determine the composition and origin of patrilineal branches in cattle.Qaidam cattle has two patrilineal branches with two paternal origins and had relatively lower paternal genetic diversity.Compared with Dachaidan, Wulan and Golmud populations, Dulan and Mangya populations had higher paternal genetic diversity in Qaidam cattle breed, showing that these two populations owned abundant genetic variations.
瑞典生命科学发展现状

全球科技经济瞭望 , 2015,
Abstract: 当前,生命科学领域的发展已成为全球关注的焦点。很多国家都将生命科学列为重点发展领域 之一。瑞典在生命科学研究领域一直保持国际先进水平,生命科学产业是瑞典主要的出口产业。面对日趋激烈的国际竞争,瑞典政府发布“2013-2016 年研究与创新法案”,宣布投资 19.6 亿克朗支持生命科学发展,重点研究方向包括:传染病和抗生素研究、老年病研究、药物研发、临床治疗技术改进以及临床实验研究等。本文分析了瑞典生命科学领域科研体制和科研经费情况、近年重点研究方向及产业概 况,并对瑞典生命科学发展现状进行了概述。
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