期刊文献+
共找到12篇文章
< 1 >
每页显示 20 50 100
Data Perturbation Analysis of the Support Vector Classifier Dual Model
1
作者 chun cai Xikui Wang 《Journal of Software Engineering and Applications》 2018年第10期459-466,共8页
The paper establishes a theorem of data perturbation analysis for the support vector classifier dual problem, from which the data perturbation analysis of the corresponding primary problem may be performed through sta... The paper establishes a theorem of data perturbation analysis for the support vector classifier dual problem, from which the data perturbation analysis of the corresponding primary problem may be performed through standard results. This theorem derives the partial derivatives of the optimal solution and its corresponding optimal decision function with respect to data parameters, and provides the basis of quantitative analysis of the influence of data errors on the optimal solution and its corresponding optimal decision function. The theorem provides the foundation for analyzing the stability and sensitivity of the support vector classifier. 展开更多
关键词 SUPPORT VECTOR CLASSIFIER PARTIAL DERIVATIVE Sensitivity STABILITY
下载PDF
推进医防融合的糖尿病全程健康管理——《国家基层糖尿病防治管理指南(2022)》解读 被引量:2
2
作者 蔡淳 贾伟平 《中华内科杂志》 CAS CSCD 北大核心 2022年第7期713-716,共4页
《国家基层糖尿病防治管理指南(2022)》在2018版基础上,基于卫生行政部门的管理要求和新近发布的相关领域研究证据,主要在糖尿病的管理要求、筛查、诊断、治疗、低血糖的识别和处理及慢性并发症检查等方面进行了更新。此外,首次增加了... 《国家基层糖尿病防治管理指南(2022)》在2018版基础上,基于卫生行政部门的管理要求和新近发布的相关领域研究证据,主要在糖尿病的管理要求、筛查、诊断、治疗、低血糖的识别和处理及慢性并发症检查等方面进行了更新。此外,首次增加了糖尿病中医药防治部分,为基层医务人员提供更全面的指导。 展开更多
关键词 糖尿病 基层卫生机构 健康管理
原文传递
Abnormal Audit Fees and Audit Opinion–Further Evidence from China's Capital Market 被引量:9
3
作者 Zanchun Xie chun cai Jianming Ye 《China Journal of Accounting Research》 2010年第Z1期51-70,共20页
The existing literature on audit opinion shopping provides inconsistent evidence on whether such shopping has any association with abnormal audit fees. In this paper, we hypothesize that firms engage in audit opinion ... The existing literature on audit opinion shopping provides inconsistent evidence on whether such shopping has any association with abnormal audit fees. In this paper, we hypothesize that firms engage in audit opinion shopping and pay an abnormal audit fee only when their degree of accounting quality is low. To examine the issue, we group firms on the basis of their change in return on assets(ROA), and show that abnormal audit fees improve audit opinions only among firms that engage local auditors and have a low degree of ROA, but report a large increase in ROA, especially when the ROA change is the result of abnormal accruals. We find no association between abnormal audit fees and audit opinion improvement for other firms. 展开更多
关键词 ABNORMAL AUDIT FEES AUDIT OPINION SHOPPING
原文传递
The effect of shared auditors in the supply chain on cost stickiness 被引量:6
4
作者 chun cai Qianwen Zheng Lei Zhu 《China Journal of Accounting Research》 2019年第4期337-355,共19页
Do supply chain audits have real effects?We focus on the effect of shared auditors in the supply chain on corporate cost stickiness.When a supplier shares auditors with its customers,the shared auditors provide inform... Do supply chain audits have real effects?We focus on the effect of shared auditors in the supply chain on corporate cost stickiness.When a supplier shares auditors with its customers,the shared auditors provide informational advantages for suppliers’managers,thus revising their optimistic or pessimistic expectations and influencing suppliers’cost stickiness.Using a sample of Chinese A-share listed companies from 2009 to 2017,we explore the relationship between shared auditors and suppliers’cost stickiness conditional on management expectations.The results show that shared auditors in the supply chain reduce suppliers’cost stickiness significantly when suppliers’managers hold optimistic expectations,and increase suppliers’cost stickiness in cases of pessimistic expectations.Furthermore,the greater the number of shared auditors,the stronger the effect.Such effects are more pronounced when supplier firms share auditors with important customers,have higher demand uncertainty,and use big 10 auditors. 展开更多
关键词 SHARED AUDITORS COST STICKINESS Management expectations Information ENVIRONMENT Supply CHAIN
原文传递
Ultrasound enhanced heterogeneous activation of peroxydisulfate by bimetallic Fe-Co/GAC catalyst for the degradation of Acid Orange 7 in water 被引量:16
5
作者 chun cai Liguo Wang +2 位作者 Hong Gao Liwei Hou Hui Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第6期1267-1273,共7页
Bimetallic Fe-Co/GAC (granular activated carbon) was prepared and used as heterogeneous catalyst in the ultrasound enhanced heterogeneous activation of peroxydisulfate (PS, S2O8 2-) process. The effect of initial ... Bimetallic Fe-Co/GAC (granular activated carbon) was prepared and used as heterogeneous catalyst in the ultrasound enhanced heterogeneous activation of peroxydisulfate (PS, S2O8 2-) process. The effect of initial pH, PS concentration, catalyst addition and stirring rate on the decolorization of Acid Orange 7 (AO7) was investigated. The results showed that the decolorization efficiency increased with an increase in PS concentration from 0.3 to 0.5 g/L and an increase in catalyst amount from 0.5 to 0.8 g/L. But further increase in PS concentration and catalyst addition would result in an unpronounced increase in decolorization efficiency. In the range of 300 to 900 r/min, stirring rate had little effect on AO7 decolorization. The catalyst stability was evaluated by measuring decolorization efficiency for four successive cycles. 展开更多
关键词 Fe-Co/GAC ultrasound heterogeneous catalysis peroxydisulfate sulfate radicals
原文传递
Effectiveness of quality of care for patients with type 2 diabetes in China:findings from the Shanghai Integration Model(SIM) 被引量:2
6
作者 chun cai Yuexing Liu +8 位作者 Yanyun Li Yan Shi Haidong Zou Yuqian Bao Yun Shen Xin Cui Chen Fu Weiping Jia the SIM Study Group 《Frontiers of Medicine》 SCIE CSCD 2022年第1期126-138,共13页
This cross-sectional study aimed to investigate the quality of care of diabetes in Shanghai,China.A total of 173235 patients with type 2 diabetes in 2017 were included in the analysis.Profiles of risk factors and inte... This cross-sectional study aimed to investigate the quality of care of diabetes in Shanghai,China.A total of 173235 patients with type 2 diabetes in 2017 were included in the analysis.Profiles of risk factors and intermediate outcomes were determined.The patients had a mean age of 66.43±8.12(standard deviation(SD))years and a mean diabetes duration of 7.95±5.53(SD)years.The percentage of patients who achieved the target level for HbA_(1c)(<7.0%)was 48.6%.Patients who achieved the target levels for blood pressure(BP)<130/80 mmHg and low-density lipoprotein-cholesterol(LDL-c)<2.6 mmol/L reached 17.5%and 34.0%,respectively.A total of 3.8%achieved all three target levels,and the value increased to 6.8%with an adaptation of the BP target level(<140/90 mmHg)for those over 65 years.Multivariable analysis identified the factors associated with a great likelihood of achieving all three target levels:male,young age,short diabetes duration,low body mass index,macrovascular complications,no microvascular complications,prescribed with lipid-lowering medication,and no prescription of antihypertensive medication.In conclusion,nearly 50%and one-third of the patients with diabetes met the target levels for HbA_(1c)and LDL-c,respectively,with a low percentage achieving the BP target level.The percentage of patients who achieved all three target levels needs significant improvement. 展开更多
关键词 type 2 diabetes quality of care macrovascular complication microvascular complication treatment pattern EPIDEMIOLOGY
原文传递
Recent advances in special morphologic photocatalysts for NO_(x)removal 被引量:1
7
作者 Yang Yang Xiuzhen Zheng +5 位作者 Wei Ren Jiafang Liu Xianliang Fu Sugang Meng Shifu Chen chun cai 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2022年第11期137-151,共15页
The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To e... The significant increase of NO_(x)concentration causes severe damages to environment and human health.Light-driven photocatalytic technique affords an ideal solution for the removal of NO_(x)at ambient conditions.To enhance the performance of NO_(x)removal,1D,2D and 3D photocatalysts have been constructed as the light absorption and the separation of charge carriers can be manipulated through controlling the morphology of the photocatalyst.Related works mainly focused on the construction and modification of special morphologic photocatalyst,including element doping,heterostructure constructing,crystal facet exposing,defect sites introducing and so on.Moreover,the excellent performance of the photocatalytic NO_(x)removal creates great awareness of the application,which has promising practical applications in NO_(x)removal by paint(removing NO_(x)indoor and outdoor)and pavement(degrading vehicle exhausts).For these considerations,recent advances in special morphologic photocatalysts for NO_(x)removal was summarized and commented in this review.The purpose is to provide insights into understanding the relationship between morphology and photocatalytic performance,meanwhile,to promote the application of photocatalytic technology in NO_(x)degradation. 展开更多
关键词 NO_(x) REMOVAL PHOTOCATALYST Graphene C_(3)N_(4) Bi-based compounds
原文传递
Recent advances in synthesis of organosilicons via radical strategies 被引量:1
8
作者 Xueping Zhang Jingkun Fang +1 位作者 chun cai Guoping Lu 《Chinese Chemical Letters》 SCIE CAS CSCD 2021年第4期1280-1292,共13页
Organosilicon compounds play an important role in the fields of materials science,pharmacy,and organic synthesis.The development of effective approaches for the preparation of these compounds have also become a resear... Organosilicon compounds play an important role in the fields of materials science,pharmacy,and organic synthesis.The development of effective approaches for the preparation of these compounds have also become a research focus in organic synthesis.In recent years,free radical synthesis of organosilicons has been vigorously developed,which generally has the advantages of milder synthesis conditions,higher yields and selectivity,and free of precious metal catalysts compared with traditional strategies.This article reviews research progresses in the synthesis of organosilico n compounds by free radical pathways since 2016.In most cases,the radical silylation is achieved based on the reaction of silyl radicals,which are triggered by four routes including peroxide,transition-metal-induced peroxide decomposition,alkali,photocatalysis.The alkyl radicals can also initiate the radical silylation for the generation of C(sp^(3))—Si bonds. 展开更多
关键词 ORGANOSILICON Radical silylation Single electron transfer Hydrogen atom transfer PHOTOREDOX Alkyl radical
原文传递
Iodine catalyzed synthesis of the chromene derivatives in one-pot 被引量:1
9
作者 Li Yan Zeng Mei Fang Lv chun cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第12期1347-1351,共5页
Iodine catalyzed one-pot reactions of salicylaldehyde and dimolecular 1H-indene-l,3(2H)-dione, barbituric acids, 4-hydro- xycoumarin, or 4-hydroxy-6-methylpyran-2-one were performed and provided a rapid, convenient ... Iodine catalyzed one-pot reactions of salicylaldehyde and dimolecular 1H-indene-l,3(2H)-dione, barbituric acids, 4-hydro- xycoumarin, or 4-hydroxy-6-methylpyran-2-one were performed and provided a rapid, convenient and general approach to synthesize the chromene derivatives. 2-(11-Oxo-10,11-dihydroindeno[1,2-b]chromen-10-yl)-lH-indene-1,3(2H)-diones P1-P4 and 10-(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)-3-methylpyrano[4,3-b]chromen-1(1OH)-ones P8-P9 were unprecedentedly prepared and structurally identified by NMR and Mass. The confirmation of structure by single crystal X-ray crystallography is reported for P3. 展开更多
关键词 CHROMENE IODINE MCRS SALICYLALDEHYDE 1H-Indene-1 3(2H)-dion
原文传递
Supported Pt-Ni bimetallic nanoparticles catalyzed hydrodeoxygenation of dibenzofuran with high selectivity to bicyclohexane 被引量:1
10
作者 Pengyu Wu chun cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2022年第1期234-238,共5页
Catalytic hydrodeoxygenation(HDO)is one of the most effective methods to upgrade the oxygen-containing compounds derived from coal tar to valuable hydrocarbons.Herein,an efficient bimetallic catalyst Pt_(1)Ni_(4)/MgO ... Catalytic hydrodeoxygenation(HDO)is one of the most effective methods to upgrade the oxygen-containing compounds derived from coal tar to valuable hydrocarbons.Herein,an efficient bimetallic catalyst Pt_(1)Ni_(4)/MgO was prepared and applied in the HDO of dibenzofuran(DBF).High yield(95%)of the desired product bicyclohexane(BCH)was achieved at 240℃and 1.2 MPa of H_(2).Superior catalytic performance could be ascribed to the"relay catalysis"of Pt sites and Ni sites,and the reaction pathway is proposed as well.Scale-up experiment and recyclability test were also performed,which demonstrated the recyclability and promising potential application of Pt_(1)Ni_(4)/MgO. 展开更多
关键词 HYDRODEOXYGENATION DIBENZOFURAN Bicyclohexane Bimetallic catalyst Relay catalysis
原文传递
An efficient,recoverable fluorous organocatalyst for accelerating the DABCO-promoted Morita-Baylis-Hillman reaction
11
作者 Yi Bo Huang Wen Bin Yi chun cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第9期1055-1058,共4页
A convenient method for Morita-Baylis-Hillman reaction of arylaldehydes with methyl acrylate has been developed by using fluorous-tag organocatalyst 1-[4-(perfluorooctyl)phenyl]-3-phenylthiourea and DABCO at room te... A convenient method for Morita-Baylis-Hillman reaction of arylaldehydes with methyl acrylate has been developed by using fluorous-tag organocatalyst 1-[4-(perfluorooctyl)phenyl]-3-phenylthiourea and DABCO at room temperature. The fluorous organocatalyst could be recovered from the reaction mixture by fluorous solid-phase extraction (F-SPE) with excellent purity for direct reuse. 展开更多
关键词 ORGANOCATALYST Morita-Baylis-Hillman reaction Fluorous solid phase extraction (F-SPE)
原文传递
Impact of macroeconomic policy uncertainty on opportunistic insider trading
12
作者 chun cai Ruixue Bao +1 位作者 Peng Wang Huiyan Yang 《China Journal of Accounting Research》 2022年第4期89-109,共21页
The macroeconomic policy environment affects the internal governance of microenterprises,which may provide opportunities for management to benefit from stock sales while decreasing its motivation to manipulate stock t... The macroeconomic policy environment affects the internal governance of microenterprises,which may provide opportunities for management to benefit from stock sales while decreasing its motivation to manipulate stock transactions.Using a sample of Chinese A-share listed companies from 2007 to2018,we study the impact of macroeconomic policy uncertainty on opportunistic insider trading.The results show that macroeconomic policy uncertainty helps restrain the opportunistic trading of shares held by management.When macroeconomic policies are uncertain,enterprises improve their internal governance.Furthermore,strengthening equity governance helps reduce management’s opportunistic use of the uncertainty of the policy environment,highlighting the advantageous effect of macroeconomic policy uncertainty and helping regulators standardize managerial behavior and promote the governance effect of macroeconomic policy. 展开更多
关键词 Macroeconomic Policy UNCERTAINTY Insider Trading OPPORTUNISM
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部