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Fermions: Spin, Hidden Variables, Violation of Bell’s Inequality and Quantum Entanglement
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作者 Doron Kwiat 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第4期1613-1627,共15页
Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s co... Using real fields instead of complex ones, it was recently claimed, that all fermions are made of pairs of coupled fields (strings) with an internal tension related to mutual attraction forces, related to Planck’s constant. Quantum mechanics is described with real fields and real operators. Schrodinger and Dirac equations then are solved. The solution to Dirac equation gives four, real, 2-vectors solutions ψ1=(U1D1)ψ2=(U2D2)ψ3=(U3D3)ψ4=(U4D4)where (ψ1,ψ4) are coupled via linear combinations to yield spin-up and spin-down fermions. Likewise, (ψ2,ψ3) are coupled via linear combinations to represent spin-up and spin-down anti-fermions. For an incoming entangled pair of fermions, the combined solution is Ψin=c1ψ1+c4ψ4where c1and c4are some hidden variables. By applying a magnetic field in +Z and +x the theoretical results of a triple Stern-Gerlach experiment are predicted correctly. Then, by repeating Bell’s and Mermin Gedanken experiment with three magnetic filters σθ, at three different inclination angles θ, the violation of Bell’s inequality is proven. It is shown that all fermions are in a mixed state of spins and the ratio between spin-up to spin-down depends on the hidden variables. 展开更多
关键词 FERMIONS SPIN hidden Variables Bell’s Inequality Violation Spin Entanglement
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Emoti-Shing: Detecting Vishing Attacks by Learning Emotion Dynamics through Hidden Markov Models
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作者 Virgile Simé Nyassi Franklin Tchakounté +3 位作者 Blaise Omer Yenké Duplex Elvis Houpa Danga Magnuss Dufe Ngoran Jean Louis Kedieng Ebongue Fendji 《Journal of Intelligent Learning Systems and Applications》 2024年第3期274-315,共42页
This study examines vishing, a form of social engineering scam using voice communication to deceive individuals into revealing sensitive information or losing money. With the rise of smartphone usage, people are more ... This study examines vishing, a form of social engineering scam using voice communication to deceive individuals into revealing sensitive information or losing money. With the rise of smartphone usage, people are more susceptible to vishing attacks. The proposed Emoti-Shing model analyzes potential victims’ emotions using Hidden Markov Models to track vishing scams by examining the emotional content of phone call audio conversations. This approach aims to detect vishing scams using biological features of humans, specifically emotions, which cannot be easily masked or spoofed. Experimental results on 30 generated emotions indicate the potential for increased vishing scam detection through this approach. 展开更多
关键词 Social Engineering hidden Markov Model Vishing Voice Mining
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Deciphering the Hidden Secrets between the Early Skin Wrinkling & the Metabolic (X) Syndrome with the Possible Reversal of This Process at the Molecular Level
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作者 Dalal Alsaadoun 《Journal of Cosmetics, Dermatological Sciences and Applications》 2024年第1期45-68,共24页
The aging process is a group of degenerative changes that physiologically occur in most of the people in the elderly. This affects one or more of the human body systems. The treatment of diseases related to the aging ... The aging process is a group of degenerative changes that physiologically occur in most of the people in the elderly. This affects one or more of the human body systems. The treatment of diseases related to the aging process has a huge impact on the economy of all nations. Aging of the skin comes on the top and despite that, the results of the already present lines of treatment are not always satisfactory. This acts as a stimulus for us to dig deeper to discover the root causes of the premature aging of the skin. This was simply caused by the accumulation of repeated minute damage to the internal structure skin. In other words, if the degree of minute damage is more than the capacity of the skin to repair, the repeated micro-damage is presented in the long run as a skin wrinkling. Moreover, the skin acts as a mirror that reflects the internal structures of the human body. Thus, the more degenerative changes in the human body systems, the more the skin could become wrinkled. Our strategy to prevent or at least slow down the aging process of the skin depends on 2 main steps;the 1<sup>st</sup> is to reduce the micro-damage as can as possible, and the 2<sup>nd</sup> is to enhance the capacity of tissue regeneration to be able to reverse the already present damaged skin. As the 2 processes are synchronized with each other, this strategy would be considered the ideal for prevention of skin wrinkling especially premature ones. This not only reverses premature skin wrinkling but also protects it from future wrinklings. This review sharply pointed out the role of the functional collagen of the dermal layer of the skin in the prevention of skin wrinklings. Therefore, it would be the target to study how collagen works in the complex machinery of the dermal layer of the skin. This concept deeply believes that the recovery of dermal collagen has a much better effect than simply ingesting collagen or receiving a topical collagen booster. . 展开更多
关键词 COLLAGEN Skin Wrinkling Glycation Hyper-Insulinemia hidden Obesity Vis-ceral Fat Inflammatory Cytokines
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Fresnel Equations Derived Using a Non-Local Hidden-Variable Particle Theory
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作者 Dirk J. Pons 《Journal of Modern Physics》 2024年第6期950-984,共35页
Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel... Problem: The Fresnel equations describe the proportions of reflected and transmitted light from a surface, and are conventionally derived from wave theory continuum mechanics. Particle-based derivations of the Fresnel equations appear not to exist. Approach: The objective of this work was to derive the basic optical laws from first principles from a particle basis. The particle model used was the Cordus theory, a type of non-local hidden-variable (NLHV) theory that predicts specific substructures to the photon and other particles. Findings: The theory explains the origin of the orthogonal electrostatic and magnetic fields, and re-derives the refraction and reflection laws including Snell’s law and critical angle, and the Fresnel equations for s and p-polarisation. These formulations are identical to those produced by electromagnetic wave theory. Contribution: The work provides a comprehensive derivation and physical explanation of the basic optical laws, which appears not to have previously been shown from a particle basis. Implications: The primary implications are for suggesting routes for the theoretical advancement of fundamental physics. The Cordus NLHV particle theory explains optical phenomena, yet it also explains other physical phenomena including some otherwise only accessible through quantum mechanics (such as the electron spin g-factor) and general relativity (including the Lorentz and relativistic Doppler). It also provides solutions for phenomena of unknown causation, such as asymmetrical baryogenesis, unification of the interactions, and reasons for nuclide stability/instability. Consequently, the implication is that NLHV theories have the potential to represent a deeper physics that may underpin and unify quantum mechanics, general relativity, and wave theory. 展开更多
关键词 Wave-Particle Duality Optical Law Fresnel Equation Non-Local hidden-Variable
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Switchable hidden spin polarization and negative Poisson's ratio in two-dimensional antiferroelectric wurtzite crystals
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作者 Zhuang Ma Jingwen Jiang +8 位作者 Gui Wang Peng Zhang Yiling Sun Zhengfang Qian Jiaxin Zheng Wen Xiong Fei Wang Xiuwen Zhang Pu Huang 《Journal of Semiconductors》 EI CAS CSCD 2023年第12期72-80,共9页
Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by... Two-dimensional(2D)antiferroelectric materials have raised great research interest over the last decade.Here,we reveal a type of 2D antiferroelectric(AFE)crystal where the AFE polarization direction can be switched by a certain degree in the 2D plane.Such 2D functional materials are realized by stacking the exfoliated wurtzite(wz)monolayers with“self-healable”nature,which host strongly coupled ferroelasticity/antiferroelectricity and benign stability.The AFE candidates,i.e.,Zn X and Cd X(X=S,Se,Te),are all semiconductors with direct bandgap atΓpoint,which harbors switchable antiferroelectricity and ferroelasticity with low transition barriers,hidden spin polarization,as well as giant in-plane negative Poisson's ratio(NPR),enabling the co-tunability of hidden spin characteristics and auxetic magnitudes via AFE switching.The 2D AFE wz crystals provide a platform to probe the interplay of 2D antiferroelectricity,ferroelasticity,NPR,and spin effects,shedding new light on the rich physics and device design in wz semiconductors. 展开更多
关键词 wurtzite crystal MULTIFERROICS hidden spin polarization negative Poisson's ratio
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Existence of hidden attractors in nonlinear hydro-turbine governing systems and its stability analysis
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作者 赵鹏翀 卫皓娟 +3 位作者 徐振坤 陈帝伊 许贝贝 王雨萌 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第9期220-228,共9页
This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The param... This work studies the stability and hidden dynamics of the nonlinear hydro-turbine governing system with an output limiting link,and propose a new six-dimensional system,which exhibits some hidden attractors.The parameter switching algorithm is used to numerically study the dynamic behaviors of the system.Moreover,it is investigated that for some parameters the system with a stable equilibrium point can generate strange hidden attractors.A self-excited attractor with the change of its parameters is also recognized.In addition,numerical simulations are carried out to analyze the dynamic behaviors of the proposed system by using the Lyapunov exponent spectra,Lyapunov dimensions,bifurcation diagrams,phase space orbits,and basins of attraction.Consequently,the findings in this work show that the basins of hidden attractors are tiny for which the standard computational procedure for localization is unavailable.These simulation results are conducive to better understanding of hidden chaotic attractors in higher-dimensional dynamical systems,and are also of great significance in revealing chaotic oscillations such as uncontrolled speed adjustment in the operation of hydropower station due to small changes of initial values. 展开更多
关键词 nonlinear hydro-turbine governing systems hidden attractors basin of attraction Lyapunov exponent spectrum
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Reliability and validity of the hidden hunger assessment scale in China-revised for high school students
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作者 Ning Zhang Minao Wang +6 位作者 Yuchen Zhang Huake Cao Yang Yang Yuhang Shi Yang Pei Feixiang Yang Yinan Du 《Global Health Journal》 2023年第2期110-116,共7页
Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves mor... Objective:Hidden hunger remains a severe public health problem that affects millions of people worldwide.In China,challenges related to dietary imbalance and hidden hunger persist.Micronutrient inadequacy deserves more attention among adolescents,given its vital role in their growth and development;however,this problem appears to have been largely ignored.High school students,in particular,are often at a high risk of hidden hunger but have limited assessment tools available.Therefore,this study aims to revise the hidden hunger assessment scale for high school students(HHAS-HSS)in China and assess its reliability and validity.Methods:Based on a literature review,expert consultation,pre-experiment,and formal survey,a hidden hunger assessment scale was revised for high school students.The formal survey involved 9336 high school students in 11 of the 16 cities in Anhui Province,China,and 9038 valid questionnaires were collected and included in the analysis.The item analysis,internal consistency reliability,test-retest reliability,content validity,exploratory factor analysis,and confirmatory factor analysis of the HHAS-HSS were examined.Results:The HHAS-HSS included a total of 4 dimensions and 12 items:"vegetables and food diversity"(three items),"fruits and dairy products"(three items),"micronutrient-dense foods"(four items),and"health condition and eating habits"(two items).The results showed a Cronbach's alpha of 0.758,a split-half reliability of 0.829,and a test-retest reliability of o.793,indicating good internal consistency.Using the Bartlett's test and Kaiser-Meyer-Olkin test(KMO)to test the exploratory factor analysis presented a four-factor model of the HHAS-HSS,the KMO0 value was 0.820(P<0.001),which indicated the possibility for factor confirmatory factor analysis.Using the maximum variance rotation method,four factors were obtained,and the cumulative variance explained rate was 57.974%.Confirmatory factor analysis also supported the division of the scale into four dimensions,and the fitting indices were x^(2)=1417.656,x^(2)/df=29.534,goodness-of-fit index=0.974,adjusted goodnessof-fit index=0.958,parsimonious goodness-of-fit index=0.600,normed fit index=0.938,incremental fit index=0.940,Tucker-Lewis index=0.917,comparative fit index=0.939,and root mean square error of approximation=0.056.Except for x^(2)/df,all the indices reached the fitting standard,and the above results showed that the construct validity of the scale reached an acceptable level.Conclusions:The HHAS-HSS has good validity and reliability for Chinese high school students.It is a convenient self-report measure of hidden hunger risk. 展开更多
关键词 hidden hunger Reliability and validity Assessment scale High school student MICRONUTRIENTS
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Application of"Six Thinking Hats"in the Investigation and Improvement of Hidden Dangers in Food Safety
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作者 Peng WAN Zhen ZHAO +3 位作者 Guoyan WEN Yunshuang FU Cuizhi LI Zhiyong LU 《Asian Agricultural Research》 2023年第10期20-22,共3页
With the development of economy,people's living standards are constantly improving,and the requirements for food safety are getting higher and higher.The Food Safety Law stipulates that enterprises should implemen... With the development of economy,people's living standards are constantly improving,and the requirements for food safety are getting higher and higher.The Food Safety Law stipulates that enterprises should implement the main responsibility of food safety,and the investigation and improvement of food safety hazards plays an important role in improving the food safety management level of enterprises and reducing food safety risks.This paper combines the innovative thinking mode of six thinking hats with food safety,discusses the application mode of six thinking hats in food safety investigation and improvement,and hopes to improve food safety level through this way. 展开更多
关键词 Six thinking hats Food safety hidden danger investigation and improvement
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Hidden Hierarchy Based on Cipher-Text Attribute Encryption for IoT Data Privacy in Cloud
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作者 Zaid Abdulsalam Ibrahim Muhammad Ilyas 《Computers, Materials & Continua》 SCIE EI 2023年第7期939-956,共18页
Most research works nowadays deal with real-time Internetof Things (IoT) data. However, with exponential data volume increases,organizations need help storing such humongous amounts of IoT data incloud storage systems... Most research works nowadays deal with real-time Internetof Things (IoT) data. However, with exponential data volume increases,organizations need help storing such humongous amounts of IoT data incloud storage systems. Moreover, such systems create security issues whileefficiently using IoT and Cloud Computing technologies. Ciphertext-Policy Attribute-Based Encryption (CP-ABE) has the potential to make IoT datamore secure and reliable in various cloud storage services. Cloud-assisted IoTssuffer from two privacy issues: access policies (public) and super polynomialdecryption times (attributed mainly to complex access structures). We havedeveloped a CP-ABE scheme in alignment with a Hidden HierarchyCiphertext-Policy Attribute-Based Encryption (HH-CP-ABE) access structure embedded within two policies, i.e., public policy and sensitive policy.In this proposed scheme, information is only revealed when the user’sinformation is satisfactory to the public policy. Furthermore, the proposedscheme applies to resource-constrained devices already contracted tasks totrusted servers (especially encryption/decryption/searching). Implementingthe method and keywords search resulted in higher access policy privacy andincreased security. The new scheme introduces superior storage in comparisonto existing systems (CP-ABE, H-CP-ABE), while also decreasing storage costsin HH-CP-ABE. Furthermore, a reduction in time for key generation canalso be noted.Moreover, the scheme proved secure, even in handling IoT datathreats in the Decisional Bilinear Diffie-Hellman (DBDH) case. 展开更多
关键词 Bilinear Diffie-Hellman(DBDH) Internet of Things(IoT) Ciphertext-Policy Attribute-Based Encryption(CP-ABE) hidden Hierarchy CP-ABE(HH-CP-ABE)
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虚拟社区激励措施对用户知识贡献倾向的影响机理研究 被引量:1
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作者 张红超 王茜 容哲 《管理学报》 CSSCI 北大核心 2024年第3期427-434,444,共9页
基于SOR理论和隐马尔科夫模型,采用马蜂窝旅游虚拟社区用户知识贡献行为数据和激励数据,探讨外在激励如何通过用户知识贡献倾向影响其知识贡献行为。研究表明:依据构建的隐马尔科夫模型,挖掘用户具有沉默、参与、积极3种隐含的知识贡献... 基于SOR理论和隐马尔科夫模型,采用马蜂窝旅游虚拟社区用户知识贡献行为数据和激励数据,探讨外在激励如何通过用户知识贡献倾向影响其知识贡献行为。研究表明:依据构建的隐马尔科夫模型,挖掘用户具有沉默、参与、积极3种隐含的知识贡献倾向;同一知识贡献倾向下,用户首次回答问题时间越早、旅游经验越丰富、累计贡献数量越多,用户知识贡献数量就越多;物质激励、精神激励以及二者联合激励与用户动态变化知识贡献倾向匹配,才能取得正向的激励作用。 展开更多
关键词 知识贡献倾向 激励措施 隐含倾向 隐马尔科夫模型
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Hidden Hearing Loss: Causes, Current Knowledge, and Future Directions
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作者 Alexandra Jalkh 《International Journal of Otolaryngology and Head & Neck Surgery》 2023年第3期107-123,共17页
Introduction: Hidden hearing loss (HHL) is a type of auditory disorder that affects the auditory neural processing and hearing sensitivity in subjects with normal hearing thresholds. Unlike central auditory processing... Introduction: Hidden hearing loss (HHL) is a type of auditory disorder that affects the auditory neural processing and hearing sensitivity in subjects with normal hearing thresholds. Unlike central auditory processing disorders, HHL happens when the cochlea (the peripheral auditory organ) is affected. There are several known risk factors to HHL which includes noise exposure, ototoxic drugs, and peripheral neuropathies, and age. Recent studies have shed light on this type of hearing loss, its etiology, prevalence, and how it can affect the auditory acuity in humans. Methods: This paper covers the current research regarding HHL, its causes, the different mechanisms involved in this disorder, and the diagnosis and potential treatments related to it. We will delve deeply into different researches concerning HHL. 4 articles from 285 were selected focusing on normal hearing individuals with bad speech intelligibility were discussed in this paper. In addition, articles discussing the effects of noise exposure on hearing impaired individuals were not considered as this study solely aims to focus on normal hearing sensitivity individuals with HHL, resulting in 4 articles from 285. Results: Numerous literatures over the decades have suggested that HHL is due to the degeneration of cochlear ribbon synapses, or hair cells synapses without hair cell damage. Their association with HHL was noted several times through this study, whether we were studying the effect of noise exposure, of age, or of ototoxicity. In all cases, no significant hair cell damage was observed, and normal thresholds were recovered. However, a decline in the amplitude of Auditory Brainstem Response (ABR) peak I from auditory nerve (AN) responses in noise exposed subjects and a decline in compound action potential (CAP) was measured when certain drugs were applied to the round window of Guinea pigs. Conclusion: Most studies, have proven that cochlear synaptophysin is the major contributor to noise induced, age, and ototoxic related HHL. There are several audiometric tests that were used to help identify HHL including Puretone audiometry in background noise, ABR, CAP, Distortion Product Otoacoustic Emission (DPOAE). 展开更多
关键词 hidden Hearing Loss Speech Testing Speech Intelligibility Noise Induced Hearing Loss OTOTOXICITY Schwan’s Cells Ablation
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隐性关联关系与审计费用——基于供应链工商大数据的研究 被引量:3
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作者 黄世忠 叶钦华 陈雪颖 《审计研究》 CSSCI 北大核心 2024年第2期73-86,共14页
近年来,上市公司将其供应链商业关系隐藏化以规避信息披露要求的趋势越来越明显,不利于投资者评估和判断上市公司的交易性质和盈利能力。本文从审计师角度出发,以2010-2021年度我国A股上市公司为研究对象,基于供应链工商大数据度量隐性... 近年来,上市公司将其供应链商业关系隐藏化以规避信息披露要求的趋势越来越明显,不利于投资者评估和判断上市公司的交易性质和盈利能力。本文从审计师角度出发,以2010-2021年度我国A股上市公司为研究对象,基于供应链工商大数据度量隐性关联关系,分析隐性关联关系与审计费用之间的关系,结果发现上市公司与重要交易对象之间存在隐性关联关系提高了审计费用,一系列稳健性检验结果保持一致。在渠道检验中,研究发现隐性关联关系通过影响审计师投入,进一步影响审计费用。在分组检验中,研究发现隐性关联关系对审计费用的影响在高市场化进程地区、低信息透明度的公司以及当上市公司为事务所重要客户时更为显著。本文研究为审计师如何判断隐性关联关系问题提供了经验数据。 展开更多
关键词 隐性关联关系 审计费用 信息披露 审计投入 风险补偿
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以六结合模式创新研究生课程思政的隐性育人功能 被引量:3
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作者 孙继兵 郑士建 +1 位作者 张兴华 丁贺伟 《高教学刊》 2024年第6期64-68,共5页
结合研究生迫切的创新能力需求、加重的功利性思想及淡化的思想政治素养的典型特征,提出研究生的课程教育要以提高学生的创新能力为核心,从国家-学校-学院-课程-教师-学生六个维度构建思政素材,以“六结合”模式把立德树人隐性地融入专... 结合研究生迫切的创新能力需求、加重的功利性思想及淡化的思想政治素养的典型特征,提出研究生的课程教育要以提高学生的创新能力为核心,从国家-学校-学院-课程-教师-学生六个维度构建思政素材,以“六结合”模式把立德树人隐性地融入专业课程教学中。纵向实行“案例导入→问题提炼→本质挖掘→归纳引申”的探究式四步教学法,横向贯穿价值观引导、知识传授、能力培养与人格养成四位一体的教育理念,增强思政的隐性育人功能。 展开更多
关键词 教学改革 课程思政 研究生课程 融入模式 隐性育人
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延长氨甲环酸使用时间有助于减少老年股骨转子间骨折围术期隐性失血 被引量:1
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作者 赵燕 吴凡 +4 位作者 李红 万盛钰 何瑾 朱宾仁 江从兵 《中国组织工程研究》 CAS 北大核心 2024年第36期5858-5864,共7页
背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自... 背景:股骨转子间骨折好发于老年人,手术后会出现大量的隐性失血,减少隐性失血可以降低并发症和住院时间。目的:评估延长氨甲环酸的使用时间对股骨近端防旋髓内钉治疗转子间骨折围术期隐性失血的影响。方法:选择2022年1月至2023年5月自贡市第四人民医院经急诊收治入院的老年股骨转子间骨折患者共62例,均在牵引床上闭合牵引复位后置入股骨近端防旋髓内钉治疗。根据氨甲环酸的使用时间分为2组,对照组38例在切开皮肤前15-30 min给予氨甲环酸1 g静脉滴注,3 h后追加1 g;试验组24例在对照组的基础上,术后第1天再追加氨甲环酸1 g静脉滴注每12 h一次。术前、术后当天、术后第1,3,5天均复查血常规,统计血红蛋白量和红细胞压积,理论总失血量采用Gross方程计算,同时记录两组患者并发症发生情况。结果与结论:①通过统计学分析,两组患者术中显性出血量相差较小,差异无显著性意义(P>0.05);②试验组围术期血红蛋白下降量、总失血量、隐性失血量低于对照组,差异有显著性意义(P<0.05);③试验组术后第3天的血红蛋白值、术后第1,3天的红细胞压积值高于对照组,差异有显著性意义(P<0.05);④两组术后血红蛋白和血小板计数呈下降趋势,第3天的血红蛋白值为最低值,术后第1天的血小板值为最低值,然后开始回升;⑤两组患者术后并发症发生率相比差异无显著性意义(P>0.05);⑥结果表明,术后延迟氨甲环酸的使用时间,可能有助于减少股骨近端防旋髓内钉治疗股骨转子间骨折的隐性失血量,并不会增加并发症风险。 展开更多
关键词 氨甲环酸 股骨转子间骨折 股骨近端防旋髓内钉 隐性失血 血红蛋白 血小板计数
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小尺度山区地质灾害隐患的无人机精细化识别方法与实践 被引量:1
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作者 黄海峰 张瑞 +6 位作者 周红 易武 薛蓉花 董志鸿 柳青 邓永煌 张国栋 《测绘通报》 CSCD 北大核心 2024年第1期6-11,共6页
本文针对小空间尺度范围内以滑坡、崩塌为主的山区地质灾害,提出了一套基于小型无人机摄影测量的精细化隐患识别方法。首先,针对工作区开展至少两期无人机摄影测量作业,经处理后得到实景三维模型、数字正射影像(DOM)、数字表面模型(DSM... 本文针对小空间尺度范围内以滑坡、崩塌为主的山区地质灾害,提出了一套基于小型无人机摄影测量的精细化隐患识别方法。首先,针对工作区开展至少两期无人机摄影测量作业,经处理后得到实景三维模型、数字正射影像(DOM)、数字表面模型(DSM)等精细化成果;其次,以两期DOM与DSM变化检测为主实现灾害体识别;然后,基于灾害体共性特征建立典型识别标志,并依此采用三维实景目视解译为主方法实现孕灾体识别;最后,通过地面核查确认或排除隐患。将该套方法应用到三峡库首秭归泄滩河左岸顺向斜坡区域,共识别出10处不同类型隐患,证明了方法的可行性。 展开更多
关键词 山区地质灾害 隐患识别 孕灾特征 无人机 变化检测
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一种基于SHVE的连接查询动态对称可搜索加密方案 被引量:1
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作者 黄一才 郁滨 《计算机研究与发展》 EI CSCD 北大核心 2024年第6期1545-1558,共14页
对称可搜索加密(searchable symmetric encryption,SSE)因其较高的搜索效率得到了人们的广泛关注.支持连接查询的对称可搜索加密方案可以提高方案的功能性.然而现有大部分连接查询方案不支持对加密数据库的动态更新操作,结合静态对称隐... 对称可搜索加密(searchable symmetric encryption,SSE)因其较高的搜索效率得到了人们的广泛关注.支持连接查询的对称可搜索加密方案可以提高方案的功能性.然而现有大部分连接查询方案不支持对加密数据库的动态更新操作,结合静态对称隐藏向量加密(symmetric hidden vectors encryption,SHVE)的定义,提出支持动态数据更新的动态对称隐藏向量加密(dynamic SHVE,DSHVE)的定义,并在此定义下构造了一种适用于可搜索加密应用场景的DSHVE方案.在此基础上,通过引入基于盲指数计算的不经意动态交叉标签,设计具有前向和后向隐私的向量数据存取结构,构造了支持连接查询的动态对称可搜索加密方案,给出了方案的详细工作过程和正式的安全性分析.理论分析和实验结果表明,连接查询时,该方案能够在不明显增加存储和计算开销的前提下,有效避免泄露匹配文档索引之外的结果特征.同时该方案能够仅通过单轮通信实现连接查询,具有较低的通信开销和较高的搜索效率. 展开更多
关键词 对称可搜索加密 连接查询 隐藏向量加密 前向隐私 后向隐私
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煤田震电协同勘探技术研究与应用 被引量:1
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作者 程彦 罗国平 +2 位作者 汪洋 赵镨 林建东 《中国煤炭地质》 2024年第4期68-72,共5页
近年来煤田震电协同勘探技术在设计、处理分析方面都取得了较大的发展,从采区最常使用的三维地震勘探、瞬变电磁勘探方法入手,对采集到的各种数据运用主成分分析(PCA)进行融合处理,解译煤矿采区工作面的异常地质体及富水性等隐蔽致灾因... 近年来煤田震电协同勘探技术在设计、处理分析方面都取得了较大的发展,从采区最常使用的三维地震勘探、瞬变电磁勘探方法入手,对采集到的各种数据运用主成分分析(PCA)进行融合处理,解译煤矿采区工作面的异常地质体及富水性等隐蔽致灾因素。该技术实现了三维地震、瞬变电磁勘探在数据层面的综合勘探,提高了物探解释煤矿采区工作面地质异常体(富水性)的准确性,为震电协同勘探技术体系的构建提供了新思路,为煤矿安全、高效、绿色生产提供了保障。 展开更多
关键词 煤田探测 地震勘探 电法勘探 震电协同 隐蔽致灾因素
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地方审计管理体制改革能抑制地方国有 企业金融资产配置吗? 被引量:1
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作者 窦炜 赵蕾 马莉莉 《审计与经济研究》 CSSCI 北大核心 2024年第2期11-21,共11页
以2015年末我国实施的省以下审计机关人财物管理试点改革作为准自然实验,选取2011—2020年A股地方国有企业为研究样本,利用双重差分模型实证检验地方审计管理体制改革对地方国有企业金融资产配置的影响。研究结果表明,地方审计管理体制... 以2015年末我国实施的省以下审计机关人财物管理试点改革作为准自然实验,选取2011—2020年A股地方国有企业为研究样本,利用双重差分模型实证检验地方审计管理体制改革对地方国有企业金融资产配置的影响。研究结果表明,地方审计管理体制改革有效抑制了地方国有企业金融资产配置规模。区分金融资产类别后研究发现,地方审计管理体制改革对企业显性金融资产规模的抑制效果较明显,但与隐性金融资产配置规模间无明显相关关系。进一步研究发现,当地方审计管理体制改革力度以及地方审计机关的审计强度越大时,政府审计对企业金融资产配置的抑制作用越明显。机制分析发现,地方审计管理体制改革通过规范政府干预缩减了地方国有企业显性金融资产配置规模,且在财政压力较大的地区这一抑制效果更为明显。 展开更多
关键词 地方审计管理体制改革 金融资产配置 隐性金融资产 政府审计 政府干预
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一种非常规“暗链”的清除探索
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作者 邓卫红 刘伟跃 《科技资讯》 2024年第11期55-58,共4页
网页被植入暗链是企事业网站、教育类网站上常见的攻击行为,攻击手法变化多样,往往不容易被轻易检测出来。笔者遇到了一种非常规的暗链,它并没有在网页中直接植入隐蔽的链接代码,并且该暗链无法在电脑端访问,只能在手机端打开。通过分... 网页被植入暗链是企事业网站、教育类网站上常见的攻击行为,攻击手法变化多样,往往不容易被轻易检测出来。笔者遇到了一种非常规的暗链,它并没有在网页中直接植入隐蔽的链接代码,并且该暗链无法在电脑端访问,只能在手机端打开。通过分析攻击路径、木马特点、IIS日志、暗链来源等一系列的排查和探索,终于找到了暗链实现挂网的操作流程并对其进行了清除。 展开更多
关键词 暗链 攻击路径 木马检测 服务器
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堤防光纤感知系统建立与汛期应急监控
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作者 施斌 顾凯 +4 位作者 魏广庆 张诚成 谢涛 朱鸿鹄 张丹 《工程地质学报》 CSCD 北大核心 2024年第5期1725-1736,共12页
汛期堤防安全关系到人民的生命和财产安危与社会稳定,而不断提高汛期堤防应急监控水平是减轻洪涝灾害的必然途径。本文对现有堤防的相关监测技术进行了评述,在此基础上,结合作者20余年在地质与岩土工程光纤监测理论研究、技术研发和堤... 汛期堤防安全关系到人民的生命和财产安危与社会稳定,而不断提高汛期堤防应急监控水平是减轻洪涝灾害的必然途径。本文对现有堤防的相关监测技术进行了评述,在此基础上,结合作者20余年在地质与岩土工程光纤监测理论研究、技术研发和堤防监控应用实践,梳理了汛期堤防的应急光纤监控内容;介绍了基于3Ds的分布式光纤感测技术的堤防监控原理与最新进展;构建了汛期堤防应急光纤感知系统;重点介绍了汛期堤防水位、渗流、侵蚀和形变等分布式光纤监控技术,并指出了今后的研发方向和目标,以期为我国的汛期堤防应急防控提供一个新的监控思路与技术手段。 展开更多
关键词 堤防 汛期 光纤 感知系统 监控 隐患
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