Vulnerability Detection of Ethereum Smart Contract Based on SolBERT-BiGRU-Attention Hybrid Neural Model

In recent years,with the great success of pre-trained language models,the pre-trained BERT model has been gradually applied to the field of source code understanding.However,the time cost of training a language model from zero is very high,and how to transfer the pre-trained language model to the field of smart contract vulnerability detection is a hot research direction at present.In this paper,we propose a hybrid model to detect common vulnerabilities in smart contracts based on a lightweight pre-trained languagemodel BERT and connected to a bidirectional gate recurrent unitmodel.The downstream neural network adopts the bidirectional gate recurrent unit neural network model with a hierarchical attention mechanism to mine more semantic features contained in the source code of smart contracts by using their characteristics.Our experiments show that our proposed hybrid neural network model SolBERT-BiGRU-Attention is fitted by a large number of data samples with smart contract vulnerabilities,and it is found that compared with the existing methods,the accuracy of our model can reach 93.85%,and the Micro-F1 Score is 94.02%.

Supply chain coordination with participators' risk bias under buy-back contract

Considering participators' risk bias,which is measured by the method of value at risk,the risk constraints in a two-echelon supply chain coordination under buy-back contract is equal to giving the order of an upper bound.With a risk-averse dominant enterprise(M)and a risk-neutral non-dominant one(R),the coordination which optimizes the supply chain under the risk constraints is achieved by a penalty mechanism L to reduce R's order.With risk-neutral M and risk-averse R,M can motivate R to increase his order by providing a risk subsidy K,and two cases are discussed.If the risk constraints of R cannot satisfy M's participation constraint to offer K,M will prefer to accept R's order to obtain a sub-optimization solution of the supply chain.Or else,with M's K,R's optimal order just coordinates the supply chain,which is equal to the case without risk bias,and in this situation R's risk bias only affects the profit distribution between the participators.

Modeling China's offshore production sharing contracts using meta analysis

Production sharing contracts have been used in the development of China’s offshore petroleum resources since 1982, but the mechanism in which the fiscal terms impact project economics is complicated and not well understood. The purpose of this paper is to model China’s offshore production sharing contracts using a probabilistic approach. Cash flows and economic indicators are used for a typical offshore oilfield development, and meta-models are constructed to analyze the basic features of the fiscal system. Applications of the models in contract negotiation are discussed.

MODELING THE CHAIN CONFORMATION OF POLYMER MELTS IN CONTRACTION FLOW

A constitutive model of quasi-Newtonian fluid based on the type of flow is used in abrupt planar contraction now.The numerical results from finite element analysis are consistent with experimental data for stress patterns and velocityprofiles in the flow field. The chain conformations of polymer melts are then investigated in such a planar contraction byusing the phenomenological model with internal parameters proposed by the author. That is, the shape and orientation ofpolymer chain coils are predicted and discussed in different flow regions of the contraction flow field that possess simpleshear flow, extensional flow, vortical flow, and mixed flow respectively.

Empirical Study on the Benefit Increase of New Contract Farming 1+3+X Model

For a long time,the development model of traditional rice planting industry has been single,linear,and focusing on production first and then market.However,with the low price of rice,such problems as slow technological upgrading,meager profits,and unstable rice quality in the primary industry planting units and farmers have become increasingly prominent.The integration and development of the rural primary,secondary,and tertiary industries and industrial integration have the same root.They are integrated industrial development based on technological or model innovation,vertical and horizontal integration.Three agricultural leading companies(Nanjing Tianwei Agricultural Technology Co.,Ltd.,Nanjing CHYKINGYOUNG Biological Technology Co.,Ltd.,and Jiangsu Jingshan Eco-organic Agriculture Co.,Ltd.)established an industrialization complex,and used their respective technical,operational,and market advantages to integrate and form a rice contract farming 1+3+X model.This model effectively integrates scattered rice planting,rice processing,and rice sales in Nanjing City of Jiangsu Province,and Chuzhou City of Anhui Province,and unifies planting regulations and supply of production materials,safeguards the supply of green and high-quality rice and realizes high quality and high price.In addition,it integrates farmers into the entire industrial chain of contract farming,summons up the production enthusiasm of farmers and greatly increases their income from planting production.

Improving Right Ventricle Cardiac Function for Repaired Tetralogy of Fallot Patient with Contracting Bands: A Modelling Study

Objective Patients with repaired tetralogy of Fallot(rTOF)account for the majority of cases with late onset right ventricle(RV)failure.The current surgical approach,including pulmonary valve replacement/insertion(PVR),has yielded mixed results with some patients recover RV function and some do not.An innovative surgical approach was proposed to help ventricle to contract and improve RV function qualified by ejection fraction with one or more active contracting bands.Computational biomechanical modelling is a widely used method in cardiovascular study for investigation of mechanisms governing disease development,quantitative diagnostic and treatment strategies and improving surgical designs for better outcome.Muscle active contraction caused by zero-load sarcomere shortening leads to change of zero-load configurations.In lieu of experimenting using real surgery on animal or human,computational simulations(virtual surgery)were performed to test different band combination and insertion options to identify optimal surgery design and band insertion plan.Methods Cardiac magnetic resonance(CMR)data were obtained from one rTOF patient(sex:male,age:22.5 y)before pulmonary valve replacement surgery.The patient was suffering from RV dilation and dysfunction with RV end-systole volume 254.49ml and end-diastole volume 406.91 mL.A total of 15 computational RV/LV/Patch/Band combination models based on(CMR)imaging were constructed to investigate the influence of different band insertion surgery plans.These models included 5 different band insertion models combined and 3 different band contraction ratio(10%,15%and 20%band zero-stress length reduction).These models included 5 different band insertion models:Model 1 with one band at anterior to the middle of papillary muscle;Model 2 with one band at posterior to the middle of papillary muscle;Model 3 with 2 bands which are the ones from Models 1&2 combined;Model 4 with a band at the base of the papillary muscle;Model 5 with 3 bands which is a combination of Models 3&4.A pre-shrink process was performed on in-vivo begin-filling and end-systole MRI data to obtain diastole and systole zero4oad ventricle geometries.An extra 5%-8%shrinkage was applied to obtain corresponding systole zero-load geometry reflecting myocardium sarcomere shortening.The zero-load band length in systole was 10%,15%and 20%shorter than that in diastole according to their corresponding contraction ratio.The nonlinear Mooney-Rivlin model was used to describe the ventricle material properties with their material parameter values adjusted to match measured data with CMR.The band material properties were in the same scale with healthy right ventricle.The RV/LV/Band model construction and solution procedures were the same as described.Results Model 5 with band contraction ratio of 20%has the ability to improve RV ejection fraction to 41.07%,which represented a 3.61%absolute improvement,or 9.6%relative improvement using pre-PVR ejection fraction as the baseline number.The ejection fractions for Models 1-4 with band contraction ratio of 20%were 39.28%,39.47%,38.87%and 40.34%respectively.Compared to models with band contraction ratio15%and 20%,models with band contraction ratio 10%has the least ability on RV ejection fraction improvement with ejection fraction 38.28%,38.00%,38.81%,38.50%and 39.36%corresponding to Models 1-5.Conclusions This pilot work demonstrated that the band insertion surgery may have great potential to improve post-PVR RV cardiac function for patients with repaired TOF.More band contraction ratio and inserted band number may lead to better post-surgery outcome.Further investigations using in-vitro animal experiments and final patient studies are warranted.

Influence of Building Information Modelling (BIM) on Engineering Contract Management in Nairobi, Kenya

Building Information Modelling (BIM) is a technology and a process that has brought changes in the construction’s traditional procurement system. Kenya lacks contractual guidelines on implementation of BIM;this makes the adoption of BIM slow and difficult. Previous research has identified a gap in contractual relationships, roles and resulting risks. The objectives of this study were to investigate BIM adoption in Nairobi and to investigate the influence of BIM on Engineering Contract Management (ECM) in Nairobi Kenya. The survey research was a descriptive study with 175 responsive questionnaires. Respondents comprised of Civil Engineers, Construction Project Managers, Architects, Quantity Surveyors, Contractors and Facility Managers. Data was collected through self-administered questionnaire and in-depth interview. Descriptive analytics, correlation and Exploratory factor analysis methods were used to analyse quantitative data. Qualitative data was analysed thematically. It emerged that adoption level was at 56.6% and shallow understanding of BIM capabilities remains to be a barrier to its adoption and implementation. It also emerged that BIM improves ECM;when time, cost, quality, collaboration and return on investment improve, ECM becomes easier. Latent factors found in BIM and ECM relationship were Legal Implications, awareness and knowledge, efficiency, versatility, mandate and leadership, and competitiveness. Further, the study found out that BIM influence on ECM demands for establishment of standards, guidelines, policy, legal framework, and regulations, which can be achieved by amending the public procurement act which dictates the operation of all the other standard forms of contract. Further research should be conducted to measure whether the understanding of BIM had positively improved.

Nursing team management and construction from the perspective of psychological contract

The psychological contract is a set of personal beliefs about the reciprocal obligations and rights established in an exchange relationship,and high-level fulfillment of psychological contract helps the development of a team.This study summarizes the concept and theoretical basis of psychological contract,the influencing factors and intervention status of nurse psychological contract,and constructs a psychological contract intervention model to provide reference and reference for better construction and management of nursing teams.

基于侧链和信任管理模型的数据共享方案

为解决在不信任的区块链环境中由于数据转售而造成的用户不愿共享数据等问题,提出一种基于侧链和信任管理模型的数据共享方案。使用信任管理模型量化节点信任值,将节点信任值集成到数据共享智能合约中,为用户提供可信的共享环境和动态的访问控制接口。对联盟链进行侧链扩容,使用信任管理模型优化共识算法。规定主链使用具有拜占庭容错能力的T-PBFT算法,侧链使用仅适用于高信任场景的T-Raft算法。用户根据预先设置的阈值动态决定在主链或侧链共享数据。实验就方案的安全性和性能进行分析,表明了该方案的可行性和有效性。

考虑网络口碑的供应链定价与协调研究

随着电子商务和社交网络的迅速发展,网络口碑正在影响和改变消费者的购买习惯,并对企业决策产生重要影响。本文考虑由一个制造商和一个零售商组成的二级供应链,通过建立两阶段定价模型研究网络口碑对供应链定价和协调的影响。首先,文章分析了集中决策下网络口碑对供应链最优定价策略和整体利润的影响;其次,设计批发价契约和收益共享契约对分散决策下的供应链进行协调。研究表明:当受正面口碑影响时,系统会降低第一阶段价格,提高第二阶段价格,且口碑影响力度越大,两阶段的价格差异越小,供应链整体利润越高;当受负面口碑影响时,系统会提高第一阶段价格,降低第二阶段价格,且口碑影响力度越大,两阶段的价格差异越大,供应链整体利润越低;批发价契约无法实现供应链的协调,收益共享契约可以同时改善制造商、零售商和供应链整体利润,实现供应链协调。

基于自然语言处理的FIDIC银皮书责任追溯混合模型

建设项目实施阶段,各参与方常需要基于合同文本快速准确地追溯责任主体、规避项目纠纷。然而,冗长复杂的建设合同使得人工追责过程通常耗时易错。针对这一问题,本文基于2017版FIDIC银皮书设计了具有针对性的文本预处理机制以制作数据集,并且在深度学习框架下微调了BERT模型以提升责任句分类的准确率。在此基础上,本文进一步结合了基于规则的责任主体提取器和模糊检索算法,从而构建了检索灵活、应用稳健的FIDIC银皮书责任追溯混合模型。实证研究进一步证明了所提出模型对于国际EPC合同责任追溯的有效性。

不对称信息下的提成制销售激励合同设计

代理商销售模式下,不对称信息对制造商产品定价与销售合同设计的影响越来越不容忽视。本文基于委托代理模型,分别构建了两种信息情况下提成制激励合同模型,对比分析了信息不对称下产品定价与代理商提成的关系,以及信息不对称对代理商收益、制造商利润的影响。研究发现,制造商最优定价与高需求实现概率和努力成本密切相关,当高需求市场实现概率较小且努力成本较高时,制造商将放弃对代理商的激励,并设定较低产品价格。当制造商激励代理商努力时,不对称信息有利于提高代理商期望收益,但会降低制造商期望利润,不影响价格高低。此外,不对称信息会缩小制造商可接受的努力成本区间,当代理商努力成本较大时,制造商会因薪酬支出过高而放弃对代理商的激励,而不对称信息使得代理商薪酬进一步提高,使得制造商更倾向于不激励代理商努力,相应定价也随之降低。

流动的非粮种植与二元土地流转市场——一项土地流转中农业经营模式的双案例分析

造成土地流转市场分化现象的因素不仅包括土地禀赋、流转主体和外在环境,农业经营模式本身也会产生影响。根据不同作物的种植特性,以作物-土地关联机制为切入点,对山东某地区的非粮种植及其参照案例进行比较。研究发现,非粮种植和粮食种植之间不同的作物-土地关联机制影响经营流动性,非粮作物需要流动经营,粮食作物采取固定经营。不同的作物类型和经营模式对土地流转市场产生影响,导致流转对象、合约形式和流转价格发生分化,呈现出二元土地流转市场形态。特别是非粮作物与粮食作物在土壤损害、种植风险、关系强度和交易成本等方面的差异,导致非粮种植的土地流转价格远高于粮食种植。

不同数字技术投资模式决策及其对绿色供应链定价影响

将数字技术投资模式引入绿色供应链定价决策中,分别构建数字技术固定投资模式和边际投资模式情形下的供应链模型,研究不同数字技术投资模式对绿色供应链定价决策影响.研究发现,(1)两种模式下,制造商分别存在一个改善自身利润的数字技术投资成本阈值,存在一个数字技术投资合作区间,提出零售商收益分享+罗宾斯坦恩讨价还价模型达成供应链双赢;(2)数字技术边际投资模式下的批发价(零售价)大于数字技术固定投资模式下的批发价格,但数字技术固定投资模式下的产品绿色度比数字技术边际投资模式下大;(3)两种数字技术投资模式都能带来零售商利润的改善,且零售商利润在数字技术固定投资模式下更大.相同数字技术投资总成本下,数字技术固定投资模式更有利于提高供应链成员企业的利润.

农户分化对农户林地承包经营不履责行为的影响

依据2021年南方集体林区4个省400个样本农户的调查数据,分别采用Logit模型及中介效应模型研究农户分化对农户林地承包经营不履责行为的现实影响。研究表明:农户分化对农户林地承包不履责行为的发生及规模具有显著正向影响;高分化程度农户与较低分化程度农户相比,农户林地承包不履责行为受户主特征及林地特征因素影响更为显著;农户分化能够通过提高村内林业生产资本投资对农户林地承包经营不履责行为产生抑制性影响。故此,应在建立农户林地承包经营履责约束机制以及差异化激励机制以促进农户林地承包责任制落实的同时,通过强化引导和扩大林业资本投资的林业财政金融支持政策来抑制和克服农户分化对农户林地承包经营不履责行为的影响。

融合词汇边界信息的合同实体识别方法

针对合同中实体表达形式复杂多变、识别粒度细的特点,及合同文本中实体较长问题,提出一种融合词汇边界信息的合同实体识别方法。利用预训练语言模型动态生成语义向量作为模型输入;运用相对位置编码对Transformer结构进行改进,使其在编码过程中融合词汇信息,进一步丰富语义特征;通过条件随机场(CRF)结构进行解码,得到输入序列的标签预测。实验结果表明,该方法可以有效确定合同文本中的实体边界,具有良好的泛化性能。

论横琴粤澳深度合作区规则衔接的示范法路径:以合同法为例

从粤港澳大湾区到横琴粤澳深度合作区,在“一国两制”原则下构建统一营商环境的过程中,民商事法律制度及规则的衔接已经成为区域经济一体化发展的现实需求和必然趋势。在践行法律衔接的过程中,除了灵活使用冲突法规则、加强跨境司法合作等方式外,通过起草示范法来推进不同法域间民商事规则的趋同对国家区域法治的发展具有长远的意义。本文以合同法领域为例,通过梳理、比较及归纳内地与澳门特别行政区法律制度中的“同类项”,探索通过示范法路径实现琴澳民商事规则衔接的可能性。

面向车联网的联邦学习模型定制框架及算法改进

针对车联网联邦学习服务难以满足用户训练个性化模型的需求,提出一种创新性的车联网联邦学习模型定制化服务框架。该框架采用了一种融合设备贡献度和数据集相似性的联邦学习聚合算法,实现了个性化联邦学习。该算法通过不同权重分配方式和相似性计算,使得不同用户可以根据自己的需求和数据特征,选择合适的模型训练方案。该框架还提出了一种双重抽样验证方法,解决了模型性能和可信度问题;此外,利用智能合约支持数据协作,保障了数据的安全性。实验结果表明,提出算法在大多数实验场景中表现出较高的准确率,该框架可以显著提高车联网服务的个性化水平,同时保证模型的准确性和可靠性。

“筋出槽”大鼠模型骨骼肌形态学和功能的特征性变化

背景:“筋出槽”是被《国际疾病分类第十一次修订本》收录的疾病名称,也是手法、针刺等治疗的临床指征,但其具体的效应机制尚不明确,亟待建立一种可以反映其临床特征和病理特点的动物模型,以便深入研究其临床治疗方法的作用机制。目的:基于骨骼肌等长收缩建立大鼠“筋出槽”疾病动物模型,探究“筋出槽”后大鼠骨骼肌形态学和功能的特征性变化。方法:60只大鼠随机分为对照组、静态负荷组和额外负重组,每组20只。对照组大鼠正常饲养,不做处理;后两组采用作者课题组设计的静态负荷悬挂造模装置固定大鼠,通过施加静态负荷(以大鼠自身体质量作为静态负荷)使大鼠上肢肌肉持续的等长收缩,建立“筋出槽”损伤模型;额外负重组在静态负荷组的基础上于大鼠踝关节处额外施加体质量50%的质量。分别于造模2,4周后取材,测试大鼠四肢抓力、骨骼肌湿质量、血清肌肌酸激酶和乳酸脱氢酶A水平的改变情况,观察大鼠骨骼肌组织形态学和超微结构的变化。结果与结论:①2周时,模型组(静态负荷组和额外负重组)大鼠抓力显著降低,骨骼肌湿质量显著下降,血清肌肌酸激酶和乳酸脱氢酶A水平显著上升,肌纤维形态结构异常,伴有大量胶原纤维沉积,电镜结果显示肌原纤维结构紊乱,Z线扭曲,明暗界限模糊;②4周时,模型组大鼠抓力较2周有所上升,血清肌肌酸激酶和乳酸脱氢酶A水平下降,肌纤维形态和超微结构的改变均有不同程度恢复;③提示基于骨骼肌持续等长收缩建立的大鼠骨骼肌损伤模型,2周时可良好反映“筋出槽”的病理特点,可用于进行针刺、手法等治疗“筋出槽”的效应机制研究。

“刚”“柔”并济的新型技术创新风控模式的构建——基于中科金财的探索性案例研究

快速变化的环境加剧了科技型企业的技术创新风险,企业需要构建兼具快变“弹性”和管控“刚性”的新型技术创新风控模式。将不完全契约理论嵌入传统风控理论,通过对中科金财独特的风控模式展开情境化研究,解锁了科技型企业构建“刚”“柔”并济风控模式的过程。具体而言,首先,企业应下沉风控单元,形成“虚拟小微企业”,加快反应速度,获取风控“弹性”,同时通过业绩认证保持必要的财务“刚性”;其次,构建“多层联盟”的风控结构,一方面通过动态调整增加结构“弹性”,另一方面则通过新规则稳固内部关系,既保证管控“刚性”,又实现对创新失败的容错“弹性”;最后,构建了“虚拟小微企业+多层联盟”的新型技术创新风控模式。基于技术创新的本质特征发展了风控理论,同时对不完全契约理论做出了一定的贡献。