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Risk-Balanced Routing Strategy for Service Function Chains of Cyber-Physical Power System Considering Cross-Space Cascading Failure
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作者 He Wang Xingyu Tong +2 位作者 Huanan Yu XiaoHu Jing Bian 《Energy Engineering》 EI 2024年第9期2525-2542,共18页
Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat t... Cyber-physical power system(CPPS)has significantly improved the operational efficiency of power systems.However,cross-space cascading failures may occur due to the coupling characteristics,which poses a great threat to the safety and reliability of CPPS,and there is an acute need to reduce the probability of these failures.Towards this end,this paper first proposes a cascading failure index to identify and quantify the importance of different information in the same class of communication services.On this basis,a joint improved risk-balanced service function chain routing strategy(SFC-RS)is proposed,which is modeled as a robust optimization problem and solved by column-and-constraint generation(C-CG)algorithm.Compared with the traditional shortest-path routing algorithm,the superiority of SFC-RS is verified in the IEEE 30-bus system.The results demonstrate that SFC-RS effectively mitigates the risk associated with information transmission in the network,enhances information transmission accessibility,and effectively limits communication disruption from becoming the cause of cross-space cascading failures. 展开更多
关键词 Cyber-physical power system service function chain risk balance routing optimization cascading failure
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Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells
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作者 Jing Zhang James Mcgettrick +11 位作者 Kangyu Ji Jinxin Bi Thomas Webb Xueping Liu Dongtao Liu Aobo Ren Yuren Xiang Bowei Li Vlad Stolojan Trystan Watson Samuel D.Stranks Wei Zhang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第2期240-248,共9页
Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocol... Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based devices.Here,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge carriers.Through further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport materials.Thanks to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced significantly.In addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability. 展开更多
关键词 fast and balanced charge transfer inverted perovskite solar cells long-term stability low-temperature processing metal oxides
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Separate-layer balanced waterflooding development technology for thick and complex carbonate reservoirs in the Middle East
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作者 SONG Xinmin LI Yong +6 位作者 LI Fengfeng YI Liping SONG Benbiao ZHU Guangya SU Haiyang WEI Liang YANG Chao 《Petroleum Exploration and Development》 SCIE 2024年第3期661-673,共13页
Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic... Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs. 展开更多
关键词 the Middle East thick carbonate reservoir vertical heterogeneity concealed baffle and barrier sealing separated development units balanced waterflooding
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Linking Perceived Risk of Public Health Emergency to Psychological Distress among Chinese College Students: The Chain Mediation Role of Balanced Time Perspective and Negative Coping Styles
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作者 Biru Chang Shengqiang Zhu +1 位作者 Qian Xie Yanghui Dai 《International Journal of Mental Health Promotion》 2024年第8期599-610,共12页
Background:With public health emergencies(PHE)worldwide increasing,the perceived risk of PHE has been one of the critical factors influencing college students’psychological distress.However,the mechanisms by which th... Background:With public health emergencies(PHE)worldwide increasing,the perceived risk of PHE has been one of the critical factors influencing college students’psychological distress.However,the mechanisms by which the perceived risk of PHE affects college students’psychological distress are not clear.The study’s purpose was to investigate the mediation roles of deviation from a balanced time perspective(DBTP)and negative coping styles between the perceived risk of PHE and psychological distress.Methods:A convenience sampling method was used to survey 1054 Chinese college students with self-reporting.Data was collected using the Public Risk Perception Scale(PRPS),the Zimbardo Time Perspective Inventory(ZTPI),the Simplified Coping Style Questionnaire(SCSQ),the PHE Anxiety Scale,and the Chinese version of the Patient Health Questionnaire(PHQ).The associations between the perceived risk of PHE,DBTP,negative coping styles,and psychological distress were clarified using the correlation analysis.Additionally,the mediating roles of DBTP and negative coping styles between the perceived risk of PHE and psychological distress were investigated using a structural equation model.Results:The findings revealed low to moderate correlations between the variables studied.Students’perceived risk of PHE was a positive predictor of their psychological distress(b=0.219,p<0.01).DBTP and negative coping styles played chain mediation roles between them with the effect being 0.009 and a 95%Boot CI of[0.003,0.023].This chain mediation model had an excellent fit index(χ^(2)/df=4.732,CFI=0.973,TLI=0.930,RMSEA=0.048,SRMR=0.047).Conclusion:These findings showed how the perceived risk of PHE affected college students’psychological distress.Specifically,these results suggested that improving students’mental ability to switch effectively among different time perspectives depending on task features and situational considerations and reducing their negative coping styles might be effective ways to promote their mental health. 展开更多
关键词 Perceived risk of public health emergency balanced time perspective negative coping styles psychological distress college students China
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Research on the Balanced Development of Urban and Rural Compulsory Education Through Education Resource Allocation
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作者 Kaijie Shang 《Journal of Contemporary Educational Research》 2024年第7期118-125,共8页
With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly... With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly prominent,urban educational resources are relatively rich,while rural educational resources are relatively scarce,and the balanced development of urban and rural compulsory education has become an urgent task.This paper mainly investigates and studies the distribution of urban and rural educational resources,discusses the unbalanced distribution of urban and rural educational resources and analyzes the reasons,and puts forward a series of corresponding solutions to promote the balanced development of urban and rural compulsory education. 展开更多
关键词 Urban and rural educational resources balanced development Educational resource allocation
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Multisensory mechanisms of gait and balance in Parkinson’s disease:an integrative review
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作者 Stiven Roytman Rebecca Paalanen +4 位作者 Giulia Carli Uros Marusic Prabesh Kanel Teus van Laar Nico I.Bohnen 《Neural Regeneration Research》 SCIE CAS 2025年第1期82-92,共11页
Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have ... Understanding the neural underpinning of human gait and balance is one of the most pertinent challenges for 21st-century translational neuroscience due to the profound impact that falls and mobility disturbances have on our aging population.Posture and gait control does not happen automatically,as previously believed,but rather requires continuous involvement of central nervous mechanisms.To effectively exert control over the body,the brain must integrate multiple streams of sensory information,including visual,vestibular,and somatosensory signals.The mechanisms which underpin the integration of these multisensory signals are the principal topic of the present work.Existing multisensory integration theories focus on how failure of cognitive processes thought to be involved in multisensory integration leads to falls in older adults.Insufficient emphasis,however,has been placed on specific contributions of individual sensory modalities to multisensory integration processes and cross-modal interactions that occur between the sensory modalities in relation to gait and balance.In the present work,we review the contributions of somatosensory,visual,and vestibular modalities,along with their multisensory intersections to gait and balance in older adults and patients with Parkinson’s disease.We also review evidence of vestibular contributions to multisensory temporal binding windows,previously shown to be highly pertinent to fall risk in older adults.Lastly,we relate multisensory vestibular mechanisms to potential neural substrates,both at the level of neurobiology(concerning positron emission tomography imaging)and at the level of electrophysiology(concerning electroencephalography).We hope that this integrative review,drawing influence across multiple subdisciplines of neuroscience,paves the way for novel research directions and therapeutic neuromodulatory approaches,to improve the lives of older adults and patients with neurodegenerative diseases. 展开更多
关键词 aging balancE encephalography functional magnetic resonance imaging GAIT multisensory integration Parkinson’s disease positron emission tomography SOMATOSENSORY VESTIBULAR visual
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Effects of Balanced Fertilization on Mulberry Leaf Quality and Its Active Substance Content 被引量:1
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作者 黄盖群 张烈 +6 位作者 殷浩 危玲 佟万红 刘刚 张建华 林超文 郭涛 《Agricultural Science & Technology》 CAS 2013年第4期635-639,644,共6页
This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves,... This paper study the effect of nitrogen (N, X1), phosphorus (P, X2) and potassium (K, X3) in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves, with mulberry trees in spring and autumn as the material and as per "3414" experimental design. The results showed that the qualities and active substance content of mulberry leaves changed from increasing to decreasing with its development; crude protein and solu-ble sugar achieved the peak on August 20; total flavonoid and 1-deoxynojirimycin was the highest on May 15. Fertilizations with N, P and K fertilizers at different amounts had significant effects on quality of mulberry leaf and content of active substances. Specifically, as fertilizer amount increased, the content of active sub- stances grew dramatically and achieved the highest at level 2 (X^2X=X~_). Based on fertilizer effect functions of objective yield, the recommended amounts of N, P and K fertilizers based on crude protein, soluble sugar, flavonoid content and DNJ in test sites were 718.46, 220.11 and 305.23 kg/hm2, when the highest of crude protein in mulberry leaf was 1 813.83 kg/hm2. When N, P and K fertilizers were recommended at 666.54, 204.41 and 243.18 kg/hm2, soluble sugar in mulberry leaf achieved the peak at 1 042.65 kg/hm2. When N, P and K fertilizers were at 675.96, 326.49 and 462.90 kg/hm2, flavonoid content achieved the maximum at 147.90 kg/hm2. When N, P and K fertilizers were at 720.9, 225.11 and 323.63 kg/hm2, DNJ content was the highest at 13.55 kg/hm2. 展开更多
关键词 MULBERRY balanced fertilization QUALITY Active substances
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A4~12GHz Wideband Balanced MIC Power Amplifier 被引量:1
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作者 姚小江 李滨 +2 位作者 刘新宇 陈中子 陈晓娟 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1868-1871,共4页
A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz cente... A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of + /- 0.6dB in the 4-12GHz frequency range. 展开更多
关键词 WIDEBAND Lange coupler microwave integrated circuit balanced power amplifiers
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Effects of Slow-release Fertilizer and Balanced Fertilization on Nitrogen, Phosphorus and Potassium Uptake in Peppers 被引量:1
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作者 张忠武 王建新 +4 位作者 鲁耀 段宗颜 彭荣珍 周敏 杨景华 《Agricultural Science & Technology》 CAS 2015年第7期1457-1461,共5页
Field plot experiment was conducted to study the effects of two slow-re- lease fertilizers and balanced fertilization on dry matter accumulation, yield, fertilizer use efficiency, nitrogen, phosphorus and potassium up... Field plot experiment was conducted to study the effects of two slow-re- lease fertilizers and balanced fertilization on dry matter accumulation, yield, fertilizer use efficiency, nitrogen, phosphorus and potassium uptake of peppers at Jiangna Town, Yanshan County, Yunnan Province in 2011. The results showed that the dry matter accumulation in dried pepper plant, pepper yield, nitrogen, phosphorus, potassium uptake in peppers were significantly increased in all the fertilizer treat- ments, compared with those in control (no fertilizer). Compared with conventional fertilization, balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer significantly increased dried pepper economic output by 20.94%, 17.5% and 14.54%, nitrogen uptake in dried peppers by 21.53%,18.46% and 13.19%, phosphorus uptake in dried peppers by 14.08%, 15.76% and 10.44%, potassium uptake in dried peppers by 22.66%, 15.73% and 16.28%; they also in- creased nitrogen and potassium use efficiency, but reduced potassium use efficiency due to the increased potassium addition. In treatments with balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer, the nitrogen utiliza- tion was 5.84%, 7.14% and 8.33% higher and the phosphorus utilization was 3.32%, 3.27% and 2.47% higher than those in treatment with conventional fertiliza- tion. In addition, the nitrogen application could be reduced by 20%-50% by bal- anced fertilization and the two slow-release fertilizers, thereby reducing environmen- tal pollution. Slow-release fertilizers could also reduce the frequency of fertilization and labor costs. 展开更多
关键词 Slow-release fertilizer balanced fertilization Dried pepper NPK uptake Fertilizer use efficiency
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平衡计分卡(Balanced Scorecard)新的效绩评价和战略管理系统 被引量:16
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作者 栾庆伟 尹洪亮 《大连大学学报》 2003年第1期71-73,共3页
平衡计分卡作为新兴的效绩评价系统,在美国应用已近十年。它弥补了传统效绩评价偏重财务指标的不足,增加了评价企业长期成功驱动因素的新指标。从财务、客户、内部业务和学习成长等多角度全面衡量企业效绩,并帮助管理者将组织的战略目... 平衡计分卡作为新兴的效绩评价系统,在美国应用已近十年。它弥补了传统效绩评价偏重财务指标的不足,增加了评价企业长期成功驱动因素的新指标。从财务、客户、内部业务和学习成长等多角度全面衡量企业效绩,并帮助管理者将组织的战略目标转化为实施的具体指标。着重阐述平衡计分卡的起源、特点、结构和应用及发展趋势。 展开更多
关键词 平衡计分卡 效绩评价 战略管理系统 评价方法 企业管理
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Establishment of a Mathematical Model for Mulberry Balanced Fertilization in Hilly Areas of Sichuan Province
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作者 刘刚 帅小蓉 +7 位作者 张建华 殷浩 佟万红 罗春燕 黄盖群 林超文 危玲 夏庆友 《Agricultural Science & Technology》 CAS 2012年第10期2137-2141,2146,共6页
In order to increase mulberry leaf yield and production efficiency in hilly areas of Sichuan Province through scientific fertilization,"3414",a quadratic regression design for modern fertilization,was employed to si... In order to increase mulberry leaf yield and production efficiency in hilly areas of Sichuan Province through scientific fertilization,"3414",a quadratic regression design for modern fertilization,was employed to simulate the regression relationship between mulberry leaf yield and major fertilizer elements including nitrogen(N),phosphor(P) and potassium(K) among which mulberry leaf yield was the objective function and N,P and K were the regulatory factors to fertilization level.As a result,7 types of ternary,binary and monadic quadratic fertilizer effect functions of N,P and K fertilizer elements were established.The weight of fertilizer factors in the optimal mulberry leaf yield obtained by various types of functions was in decreasing order of KPKPNPKNKNNP,and the weight of fertilizer factors in the ratio of leaf yield to input was in decreasing order of K〉PK〉NPK〉P〉NK〉NP〉N.To be specific,the ternary quadratic fertilizer effect function(Y=20 313+0.25X1+43.48 X2+34.47X3-0.01X1^2-0.14X2^2-0.06X3^2+0.05X1X2+0.02X1X3-0.07X2X3,in which X1,X2 and X3 indicate the fertilizer factors N,P and K,respectively) was a model containing all factors,thereby being a recommended fertilization program for mulberry field.Single factor effect analysis indicated that K fertilizer had the highest influence on mulberry leaf yield and ratio of leaf yield to input.Therefore,among all the simulation functions,the monadic quadratic fertilizer effect function of K fertilizer factor(Y=25 002.27+44.728X3-0.084X32) leads to the optimal leaf yield and maximum ratio of leaf yield to input.By using the optimal fertilization program with 600 kg/hm2 N,210 kg/hm2 P2O5 and 254.33 kg/hm2 K2O,the optimal economic leaf yield obtained is 30 945.00 kg/hm2,the cost of fertilizer input is 4 403.65 yuan/hm2,and the ratio of leaf yield to input is as high as 17.57.After verification by production practices,the recommended fertilization indicators in the optimal mulberry fertilization program can provide reference for the construction of high-yield mulberry field in hilly areas of Sichuan Province. 展开更多
关键词 MULBERRY High yield balanced fertilization Fertilizer effect function
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Joint eigenvalue estimation by balanced simultaneous Schur decomposition
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作者 付佗 高西奇 《Journal of Southeast University(English Edition)》 EI CAS 2006年第4期445-450,共6页
The problem of joint eigenvalue estimation for the non-defective commuting set of matrices A is addressed. A procedure revealing the joint eigenstructure by simultaneous diagonalization of. A with simultaneous Schur d... The problem of joint eigenvalue estimation for the non-defective commuting set of matrices A is addressed. A procedure revealing the joint eigenstructure by simultaneous diagonalization of. A with simultaneous Schur decomposition (SSD) and balance procedure alternately is proposed for performance considerations and also for overcoming the convergence difficulties of previous methods based only on simultaneous Schur form and unitary transformations, it is shown that the SSD procedure can be well incorporated with the balancing algorithm in a pingpong manner, i. e., each optimizes a cost function and at the same time serves as an acceleration procedure for the other. Under mild assumptions, the convergence of the two cost functions alternately optimized, i. e., the norm of A and the norm of the left-lower part of A is proved. Numerical experiments are conducted in a multi-dimensional harmonic retrieval application and suggest that the presented method converges considerably faster than the methods based on only unitary transformation for matrices which are not near to normality. 展开更多
关键词 direction of arrival multi-dimensional harmonic retrieval joint eigenvalue simultaneous Schur decomposition balance algorithm
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3D Balanced FFE序列在脑积水MRI检查中的应用 被引量:2
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作者 陈江津 余成新 +4 位作者 陆蓬 杨成 彭传琴 徐亚卡 胡燕 《临床放射学杂志》 CSCD 北大核心 2008年第6期739-741,共3页
目的探讨三维平衡全稳态快速场梯度回波(3DB-FFE)序列在脑积水成像中的临床应用价值。资料与方法采用Philips Achieva 1.5T双梯度超导型磁共振设备对50例脑室系统积水的患者进行3DB-FFE序列脑室系统成像扫描。比较该方法与常规T1WI、T2W... 目的探讨三维平衡全稳态快速场梯度回波(3DB-FFE)序列在脑积水成像中的临床应用价值。资料与方法采用Philips Achieva 1.5T双梯度超导型磁共振设备对50例脑室系统积水的患者进行3DB-FFE序列脑室系统成像扫描。比较该方法与常规T1WI、T2WI显示中脑导水管和室间孔形态的效果。结果50例患者3DB-FFE序列图像均清晰显示脑室系统,对中脑导水管和室间孔的扩张、狭窄、梗阻的程度和形态与常规SE序列T1WI、T2WI显示效果相比较,3DB-FFE序列有明显优越性。结论3DB-FFE序列脑室成像扫描能清晰显示脑室积水情况,为临床确诊和治疗提供可靠的依据,可作为一种MR脑室积水成像的新方法。 展开更多
关键词 三维平衡全稳态快速场梯度回波序列 脑室系统成像 脑积水 薄层扫描
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Balanced Big Filter-模与Cousin复形
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作者 耿玉仙 《江苏技术师范学院学报》 2003年第4期26-29,共4页
利用A-模M的深度depthAM以及Cousin复形C(D(A),M)的同调模对balancedbigfilter-模的特性进行了研究,并对C(D(A),M)的正合性进行了讨论。
关键词 balanced BIG filter-模 Cousin复形
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基于Class Balanced Loss修正交叉熵的非均衡样本信用风险评价模型 被引量:10
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作者 杨莲 石宝峰 董轶哲 《系统管理学报》 CSSCI CSCD 北大核心 2022年第2期255-269,289,共16页
针对传统信用风险预测模型存在对非违约样本识别过度、对违约样本识别不足的问题,将平衡损失Class Balanced Loss函数引入信用风险评价,构建Class Balanced Loss修正交叉熵的非均衡样本信用风险评价模型。利用所建模型与交叉熵神经网络... 针对传统信用风险预测模型存在对非违约样本识别过度、对违约样本识别不足的问题,将平衡损失Class Balanced Loss函数引入信用风险评价,构建Class Balanced Loss修正交叉熵的非均衡样本信用风险评价模型。利用所建模型与交叉熵神经网络、支持向量机、决策树、随机森林和K最近邻5种分类模型进行对比,验证BPNN-CBCE对中国某金融机构1 534笔农户贷款数据信用风险预测的有效性;在此基础上,利用UCI公开的德国信贷数据验证BPNN-CBCE模型的稳健性。研究表明:对于农户数据,BPNN-CBCE模型在AUC、违约召回率Default recall方面普遍优于BPNN-CE、SVM、DT、RF和KNN模型,其中,BPNN-CBCE的Default recall相比5种对比模型提升了41.3个百分点,AUC相比5种对比模型提升了15.6个百分点;对于德国数据集,BPNN-CBCE评级模型在AUC、违约召回率Default recall方面也均优于5种对比模型。因此,BPNN-CBCE信用评价模型对农户不均衡信贷数据中的违约样本具有较好的识别能力,可有效降低金融机构客户误判带来的损失。创新与特色:①利用Class Balanced Loss中的平衡因子ω,增大违约样本在目标损失中的权重、降低非违约样本在目标损失中的权重,客观调节正负样本损失在目标损失中权重,弥补交叉熵函数无法调节两类样本损失权重的缺陷,克服由样本不均衡带来的评价模型对非违约样本识别过度、对违约样本识别不足。②通过考虑数据重叠,利用随机覆盖方法,分别对贷款数据中违约、非违约样本进行不放回采样,以对全样本空间X_(违约)、X_(非违约)进行不重叠覆盖,计算两类贷款客户的有效样本数量。既反映由于真实数据之间的内在相似性,随着样本数量的增加,新添加样本很可能是现有样本近似重复的客观事实,也保证基于有效样本对两类样本损失进行重新加权的客观性。将图像识别领域中的Class Balanced Loss函数引入信用评价领域,既拓展了Class Balanced Loss的使用边界,也为解决不均衡样本的信用风险评价提供了新的研究思路。 展开更多
关键词 信用评价 Class balanced Loss BP神经网络 交叉熵 小额信贷
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A Study of the Balanced Scorecard: The Rockwater Case
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作者 马赫 《神州》 2017年第14期293-293,共1页
Over the past decades,various performance appraisal methods have been raised and developed by many scholars and managers for years.It seems that each kind of performance appraisal techniques has its strengths and lim... Over the past decades,various performance appraisal methods have been raised and developed by many scholars and managers for years.It seems that each kind of performance appraisal techniques has its strengths and limitations and none of them is able to avoid all of the pitfalls.Today,driven by the power of innovation,dozens of new companies are trying to reinvent the performance management tools market.This paper analyzes how the Balanced Scorecard (BSC) implemented to provide line managers with a performance appraisal system in the private sector companies through the case study of Rockwater,and critically identify its main strengths and limitations,and then make some recommendations for improvement. 展开更多
关键词 PERFORMANCE MANAGEMENT PERFORMANCE APPRAISAL balanced SCORECARD
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建筑企业管理中的Balanced Scorecard法 被引量:4
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作者 尤凤翔 杨书岫 纪晓慧 《丹东师专学报》 2002年第4期54-55,21,共3页
本文通过万科企业股份有限公司运用“Balanced Scorecard”法的案例,介绍了“Balanced Scorecard”法在建设企业管理中的应用。从财务绩效、顾客满意、业务流程、创新与成长四个方面进行了分析,提出了整合、发展的建议。
关键词 建筑企业管理 balanced Scorecard法 平衡积分卡
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A Survey of Unbalanced Flow Diagnostics and Their Application 被引量:23
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作者 Fuqing Zhang Steven E. Koch Christopher A. Davis and Michael L. Kaplan 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2000年第2期165-183,共19页
This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equatio... This paper presents an extensive survey of the most commonly used tools for diagnosing unbalanced flow in the atmosphere, namely the Lagrangian Rossby number, Psi vector, divergence equation, nonlinear balance equation, generalized omega-equation, and departure from fields obtained by potential vorticity (PV) inversion. The basic thoery, assumptions as well as implementation and limitations for each of the tools are all discussed. These tools are applied to high—resolution mesoscale model data to assess the role of unbalanced dynamics in the generation of a mesoscale gravity wave event over the East Coast of the United States. Comparison of these tools in this case study shows that these various methods agree to a large extent with each other though they differ in details. Key words Unbalanced flow - Geostrophic adjustment - Gravity waves - Nonlinear balance equation - Potential vorticity inversion - Omega equations - Rossby number This research was conducted under support from NSF grant ATM-9700626 of the United States. The numerical computations described herein were performed on the Cray T90 at the North Carolina Supercomputing Center and the Cray supercomputer at the NCAR Scientific Computing Division, which also provided the initialization fields for the MM5. Thanks are extended to Mark Stoelinga at University of Washington for the RIP post-processing package. 展开更多
关键词 Unbalanced flow Geostrophic adjustment Gravity waves Nonlinear balance equation Potential vorticity inversion Omega equations Rossby number
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INVESTIGATION INTO EFFECT OF SPRING PRESSURE ON PERFORMANCE OF BALANCED MECHANICAL SEALS 被引量:7
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作者 SUN Jianjun GU Boqin 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第3期39-43,共5页
The loads acting on the sealing elements of balanced mechanical seals are analyzed. When the balance factor approaches the back pressure factor, the spring pressure will become main part of the face pressure. The leak... The loads acting on the sealing elements of balanced mechanical seals are analyzed. When the balance factor approaches the back pressure factor, the spring pressure will become main part of the face pressure. The leakage model of balanced mechanical seals is established on the base of M-B model for rough surface. Several GY-70 type balanced mechanical seals are tested. The influences of the spring pressure both on the leakage rate and on the friction characteristic of balanced mechanical seals are investigated. The research results indicate that as spring pressure increases, both the clear-ance between two end faces and the leakage rate will decrease, and the friction will be more serious because lubrication medium between the rotating ring and the stationary ring reduces, though the increase of the spring pressure may not be enough to change the face friction state of mechanical seals. There exists an optimum spring pressure for mechanical seal operation. Under this spring pres-sure, not only leakage rate is small, but also the seal end surfaces have a fine friction characteristic. Under different operating conditions, identical type mechanical seals may possess different spring pressure. Appropriate selection of spring pressure is valuable to realize long-period and small leakage rate operating of balanced mechanical seals. 展开更多
关键词 balanced mechanical seal Spring pressure Leakage rate Friction characteristic Fractal geometry
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Mechanism of Balanced Flow and Frontogenesis 被引量:3
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作者 伍荣生 方娟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2001年第3期323-334,共12页
The final balanced state of an initial unbalanced flow is discussed with the same method as Vallis (1992). For the two-dimensional, inviscid, rotating and nonlinear model, the final state of the flow depends on the in... The final balanced state of an initial unbalanced flow is discussed with the same method as Vallis (1992). For the two-dimensional, inviscid, rotating and nonlinear model, the final state of the flow depends on the initial conditions. If the initial potential vortcity of the flow is non-uniform, the final state is not necessarily geostrophic. However, for the zero and uniform potential vorticity flow, the final state will satisfy the thermal wind relation when the length scale of the initial disturbance is large enough. Otherwise, discontinuity will occur in the geostrophic solution. In this case, the final balanced state will not be geostrophic any longer and an extended momentum coordinate is introduced to overcome the mult-value problem. Key words Frontogenesis - Geostrophic adjustment - Thermal wind balance - Extended momentum coordinates The work was supported by the National Natural Science Foundation of China (Grant Nos. 49735180 and 40075011) and the State Key Basic Program: CHERES. 展开更多
关键词 FRONTOGENESIS Geostrophic adjustment Thermal wind balance Extended momentum coordinates
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