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POEMS综合征全身系统性治疗疗效和安全性的Meta分析
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作者 张天宇 于海搏 +8 位作者 陈飞 李新 张佳佳 詹晓凯 申曼 汤然 范斯斌 赵凤仪 黄仲夏 《中国全科医学》 北大核心 2025年第27期3447-3455,共9页
背景POEMS综合征是一种危及生命的浆细胞肿瘤,以周围神经病变、脏器肿大、内分泌障碍、M蛋白病变为主要临床表现。该综合征发病率低,且预后不良。尽管对POEMS综合征的认识逐渐增加,但其确切发病机制尚不完全清晰,也无标准治疗方案。全... 背景POEMS综合征是一种危及生命的浆细胞肿瘤,以周围神经病变、脏器肿大、内分泌障碍、M蛋白病变为主要临床表现。该综合征发病率低,且预后不良。尽管对POEMS综合征的认识逐渐增加,但其确切发病机制尚不完全清晰,也无标准治疗方案。全身性系统性治疗包括自体干细胞移植(ASCT)前的短程诱导治疗和ASCT治疗,已被作为潜在的有效治疗手段。这些治疗方法旨在控制病情进展,改善症状,并提高患者生存率。目的评价诱导治疗方案马法兰联合地塞米松(MD)方案、免疫调节剂(沙利度胺或来那度胺)联合地塞米松(TD或RD方案),以及ASCT用于POEMS综合征的疗效和安全性。方法计算机检索PubMed、Embase、Cochrane Library,检索时限自建库至2024年5月,同时配合其他检索方式,收集POEMS综合征系统性疗法的随机对照试验(RCT)、非RCT、病例对照研究、队列研究等文献,采用Stata 15.1软件进行单组率Meta分析、敏感性分析和发表偏倚分析。结果共纳入14项研究,共计794例POEMS综合征患者。Meta分析结果显示:MD方案、免疫调节剂及ASCT用于治疗POEMS综合征的血液学反应率为0.800(95%CI=0.715~0.874),血管内皮生长因子(VEGF)反应率为0.872(95%CI=0.751~0.962),神经系统反应率0.796(95%CI=0.603~0.941),≥3级不良反应发生率为0.108(95%CI=0.000~0.309),末次随访时的存活率为0.940(95%CI=0.908~0.966),末次随访时的复发率为7.2%(95%CI=0.013~0.160),5年总生存率为0.917(95%CI=0.893~0.941)。亚组分析显示:血液学反应率方面,以上三种疗法分别为0.806、0.726、0.830;VEGF反应率方面,三者分别为0.958、0.887、0.800;神经系统反应率方面,三者分别为1.000、0.642、0.926;末次随访时的存活率方面,三者分别为1.000、0.978、0.908。敏感性分析显示,在逐一剔除文献后,所得结果未受到明显影响,提示本研究结果稳健。采用Egger's检验评估发表偏倚风险,经过Egger's检验,血液学反应率(P=0.777)、VEGF反应率(P=0.981)、神经系统反应率(P=0.060)、≥3级不良反应发生率(P=0.117)、末次随访时的存活率(P=0.088)及末次随访时的复发率(P=0.885)均不存在发表偏倚。结论在POEMS综合征全身性系统性治疗中,血液学反应率方面,MD方案、免疫调节剂及ASCT的治疗反应率均佳,尤其是MD方案和ASCT神经系统反应率更高,但RD方案3级以上不良反应较低,有利于长期治疗。因此,RD方案可作为POEMS综合征患者的一线治疗选择,对于年轻可耐受患者,推荐RD方案诱导治疗后接受大剂量马法兰治疗并进行ASCT。 展开更多
关键词 poemS综合征 系统性治疗 治疗反应 不良反应 META分析
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以肝脾肿大为首发表现的POEMS综合征2例报告
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作者 张野 王文清 +6 位作者 李璟 白芡蓉 李佳玉 成艳 房苗苗 高娜娜 黄长形 《临床肝胆病杂志》 北大核心 2025年第1期127-132,共6页
POEMS综合征是一种与浆细胞病有关、累及多系统的罕见病,临床表现多样。现报道2例以肝脾肿大为首发表现的POEMS综合征病例,病程中患者出现下肢无力、肝脾和淋巴结肿大、腹水、甲状腺功能减退、M蛋白阳性、皮肤色深,^(18)F-FDG PET-CT显... POEMS综合征是一种与浆细胞病有关、累及多系统的罕见病,临床表现多样。现报道2例以肝脾肿大为首发表现的POEMS综合征病例,病程中患者出现下肢无力、肝脾和淋巴结肿大、腹水、甲状腺功能减退、M蛋白阳性、皮肤色深,^(18)F-FDG PET-CT显像发现以溶骨性改变为主的骨病变,合并浆细胞瘤,血清血管内皮生长因子水平升高,最终诊断为POEMS综合征,经免疫调节治疗后症状缓解。 展开更多
关键词 poemS综合征 肝肿大 脾肿大 诊断
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以反复脑梗死为首发表现的POEMS综合征
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作者 王炎炎 洪月慧 +1 位作者 朱以诚 姚明 《中国现代神经疾病杂志》 北大核心 2025年第5期452-457,共6页
病历摘要患者男性,45岁。因肢体无力22个月,右眼视野缺损7个月,言语不清4个月,于2023年12月28日首次入院。患者22个月前(2022年2月)无明显诱因出现发作性左手无力,持续数秒后自行缓解,共发作3~5次,后直立位与他人交谈时突发头晕、恶心,... 病历摘要患者男性,45岁。因肢体无力22个月,右眼视野缺损7个月,言语不清4个月,于2023年12月28日首次入院。患者22个月前(2022年2月)无明显诱因出现发作性左手无力,持续数秒后自行缓解,共发作3~5次,后直立位与他人交谈时突发头晕、恶心,短暂性右下肢无力、站立不稳,无头痛、耳鸣、听力下降、言语不清、口角歪斜。外院住院期间(2022年2月23日)头部MRI显示左侧基底节区、侧脑室旁、双侧半卵圆中心、右侧顶叶DWI高信号(图1a,1b). 展开更多
关键词 poemS综合征 脑梗死 病例报告
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A series of iridium(Ⅲ)complexes with fluorophenyl isoquinoline ligand and low-efficiency roll-off properties:A density functional theory study
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作者 QIN Zhengkun PAN Zicong +2 位作者 TIAN Hui ZHANG Wanyi SONG Mingxing 《无机化学学报》 北大核心 2025年第6期1235-1244,共10页
We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic ligh... We have examined the theoretical implications of combining two main and three auxiliary ligands to form several Ir(Ⅲ)complexes featuring a transition metal as their core atom to identify some appropriate organic lightemitting diode(OLED)materials.By utilizing electronic structure,frontier molecular orbitals,minimum single-line absorption,triplet excited states,and emission spectral data derived from the density functional theory,the usefulness of these Ir(Ⅲ)complexes,including(piq)_(2)Ir(acac),(piq)_(2)Ir(tmd),(piq)_(2)Ir(tpip),(fpiq)_(2)Ir(acac),(fpiq)_(2)Ir(tmd),and(fpiq)_(2)Ir(tpip),in OLEDs was examined,where piq=1-phenylisoquinoline,fpiq=1-(4-fluorophenyl)isoquinoline,acac=(3Z)-4-hydroxypent-3-en-2-one,tmd=(4Z)-5-hydroxy-2,2,6,6-tetramethylhept-4-en-3-one,and tpip=tetraphenylimido-diphosphonate.These complexes all have low-efficiency roll-off properties,especially(fpiq)_(2)Ir(tpip).Some researchers have successfully synthesized complexes extremely similar to(piq)_(2)Ir(acac)through the Suzuki-Miyaura coupling reaction. 展开更多
关键词 density functional theory organic light-emitting diodes luminescent materials Ir(Ⅲ)complexes
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A new theory for determining large deformation area of roof at intersection and verification analysis
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作者 WU Yi-yi GAO Yu-bing +2 位作者 MA Xiang ZHANG Xing-xing HE Man-chao 《Journal of Central South University》 2025年第2期656-677,共22页
The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying t... The intersection is a widely used traffic line structure from the shallow tunnel to the deep roadway,and determining the subsidence hidden danger area of the roof is the key to its stability control.However,applying traditional maximum equivalent span beam(MESB)theory to determine deformation range,peak point,and angle influence poses a challenge.Considering the overall structure of the intersection roof,the maximum equivalent triangular plate(METP)theory is proposed,and its geometric parameter calculation formula and deflection calculation formula are obtained.The application of the two theories in 18 models with different intersection angles,roadway types,and surrounding rock lithology is verified by numerical analysis.The results show that:1)The METP structure of the intersection roof established by the simulation results of each model successfully determined the location of the roof’s high displacement zone;2)The area comparison method of the METP theory can be reasonably explained:①The roof subsidence of the intersection decreases with the increase of the intersection angle;②The roof subsidence at the intersection of different roadway types has a rectangular type>arch type>circular type;③The roof subsidence of the intersection with weak surrounding rock is significantly larger than that of the intersection with hard surrounding rock.According to the application results of the two theories,the four advantages of the METP theory are compared and clarified in the basic assumptions,mechanical models,main viewpoints,and mechanism analysis.The large deformation inducement of the intersection roof is then explored.The J 2 peak area of the roof drives the large deformation of the area,the peak point of which is consistent with the center of gravity position of the METP.Furthermore,the change in the range of this peak is consistent with the change law of the METP’s area.Hence,this theory clarifies the large deformation area of the intersection roof,which provides a clear guiding basis for its initial support design,mid-term monitoring,and late local reinforcement. 展开更多
关键词 roadway intersection roof deformation equivalent span theory triangular plate structure numerical analysis stress partial tensor
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来那度胺联合自体造血干细胞移植治疗POEMS综合征1例及文献复习
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作者 张权娥 陈月 +3 位作者 张丽娟 丁亦含 王春玲 何正梅 《南京医科大学学报(自然科学版)》 CAS 北大核心 2024年第2期293-296,共4页
POEMS综合征(POEMS syndrome)是一种罕见的克隆性浆细胞病,Bardwick等[1]于1980年根据该疾病主要症状的首字母:多发性神经病(polyneuropathy)、脏器肿大(organmegaly)、内分泌异常(endocrinopathy)、M蛋白(mprotein)、皮肤改变(skin cha... POEMS综合征(POEMS syndrome)是一种罕见的克隆性浆细胞病,Bardwick等[1]于1980年根据该疾病主要症状的首字母:多发性神经病(polyneuropathy)、脏器肿大(organmegaly)、内分泌异常(endocrinopathy)、M蛋白(mprotein)、皮肤改变(skin changes),提出了POEMS综合征的命名方式。POEMS综合征的临床表现复杂,涉及多个学科,并且没有特定的检查方法,所以POEMS综合征早期容易漏诊或误诊。该病发病机制尚不清,可能与细胞因子失衡相关。 展开更多
关键词 poemS综合征 来那度胺 自体造血干细胞移植
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Prediction and critical transition mechanism for granite fracture:Insights from critical slowing down theory 被引量:2
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作者 WANG Chun-lai ZHOU Bao-kun +6 位作者 LI Chang-feng WEN Zhi-jie BAI Zhi-an ZHU Chao-yang SUN Liang XUE Xu-hui CAO Peng 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第8期2748-2764,共17页
Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteris... Rock fracture warning is one of the significant challenges in rock mechanics.Many true triaxial and synchronous acoustic emission(AE)tests were conducted on granite samples.The investigation focused on the characteristics of AE signals preceding granite fracture,based on the critical slowing down(CSD)theory.The granite undergoes a transition from the stable phase to the fracture phase and exhibits a clear CSD phenomenon,characterized by a pronounced increase in variance and autocorrelation coefficient.The variance mutation points were found to be more identifiable and suitable as the primary criterion for predicting precursor information related to granite fracture,compared to the autocorrelation coefficient.It is noteworthy to emphasize that the CSD factor holds greater potential in elucidating the underlying mechanisms responsible for the critical transition of granite fracture,in comparison to the AE timing parameters.Furthermore,a novel multi-parameter collaborative prediction method for rock fracture was developed by comprehensively analyzing predictive information,including abnormal variation modes and the CSD factor of AE characteristic parameters.This method enhances the understanding and prediction of rock fracture-related geohazards. 展开更多
关键词 GRANITE triaxial compression acoustic emission rock fracture critical slowing down theory
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Transient response of doubly-curved bio-inspired composite shells resting on viscoelastic foundation subject to blast load using improved first-order shear theory and isogeometric approach 被引量:1
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作者 Thuy Tran Thi Thu Tu Nguyen Anh +1 位作者 Hue Nguyen Thi Hong Nguyen Thi 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第8期171-193,共23页
Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties... Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures. 展开更多
关键词 Blast load Modified first-order shear theory Biological composite structures
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Complex adaptive system theory,agent-based modeling,and simulation in dominant technology formation 被引量:1
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作者 ZHANG Ruihan SUN Bing 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期130-153,共24页
Dominant technology formation is the key for the hightech industry to“cross the chasm”and gain an established foothold in the market(and hence disrupt the regime).Therefore,a stimulus-response model is proposed to i... Dominant technology formation is the key for the hightech industry to“cross the chasm”and gain an established foothold in the market(and hence disrupt the regime).Therefore,a stimulus-response model is proposed to investigate the dominant technology by exploring its formation process and mechanism.Specifically,based on complex adaptive system theory and the basic stimulus-response model,we use a combination of agent-based modeling and system dynamics modeling to capture the interactions between dominant technology and the socio-technical landscape.The results indicate the following:(i)The dynamic interaction is“stimulus-reaction-selection”,which promotes the dominant technology’s formation.(ii)The dominant technology’s formation can be described as a dynamic process in which the adaptation intensity of technology standards increases continuously until it becomes the leading technology under the dual action of internal and external mechanisms.(iii)The dominant technology’s formation in the high-tech industry is influenced by learning ability,the number of adopting users and adaptability.Therein,a“critical scale”of learning ability exists to promote the formation of leading technology:a large number of adopting users can promote the dominant technology’s formation by influencing the adaptive response of technology standards to the socio-technical landscape and the choice of technology standards by the socio-technical landscape.There is a minimum threshold and a maximum threshold for the role of adaptability in the dominant technology’s formation.(iv)The socio-technical landscape can promote the leading technology’s shaping in the high-tech industry,and different elements have different effects.This study promotes research on the formation mechanism of dominant technology in the high-tech industry,presents new perspectives and methods for researchers,and provides essential enlightenment for managers to formulate technology strategies. 展开更多
关键词 complex adaptive system theory agent-based modeling and simulation dominant technology socio-technical landscape adaptation-choice
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UpToDate临床顾问在疑难病诊断中的应用--以POEMS综合征为例
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作者 张妲 周广鑫 肖黎 《医学与哲学》 北大核心 2024年第18期73-76,共4页
以一例POEMS综合征为例,展示如何使用UpToDate临床顾问辅助疑难病的诊断。详细描述一位54岁女性患者的临床资料、检查结果和治疗过程,根据病例特点,借助UpToDate临床顾问梳理包括糖尿病性多发性神经病的筛查、库欣综合征确诊、低促性腺... 以一例POEMS综合征为例,展示如何使用UpToDate临床顾问辅助疑难病的诊断。详细描述一位54岁女性患者的临床资料、检查结果和治疗过程,根据病例特点,借助UpToDate临床顾问梳理包括糖尿病性多发性神经病的筛查、库欣综合征确诊、低促性腺激素性性腺功能减退症病因、慢性炎症性脱髓鞘性多发性神经病的诊断等专业知识和临床诊断思路,在多学科合作基础上,逐渐明晰诊断证据,并通过UpToDate临床顾问和PubMed数据库的互补合用,实现对临床病情全面解读。 展开更多
关键词 疑难病 poemS 综合征 UpToDate 临床顾问 临床思维
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Belief exponential divergence for D-S evidence theory and its application in multi-source information fusion 被引量:2
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作者 DUAN Xiaobo FAN Qiucen +1 位作者 BI Wenhao ZHANG An 《Journal of Systems Engineering and Electronics》 CSCD 2024年第6期1454-1468,共15页
Dempster-Shafer evidence theory is broadly employed in the research of multi-source information fusion.Nevertheless,when fusing highly conflicting evidence it may pro-duce counterintuitive outcomes.To address this iss... Dempster-Shafer evidence theory is broadly employed in the research of multi-source information fusion.Nevertheless,when fusing highly conflicting evidence it may pro-duce counterintuitive outcomes.To address this issue,a fusion approach based on a newly defined belief exponential diver-gence and Deng entropy is proposed.First,a belief exponential divergence is proposed as the conflict measurement between evidences.Then,the credibility of each evidence is calculated.Afterwards,the Deng entropy is used to calculate information volume to determine the uncertainty of evidence.Then,the weight of evidence is calculated by integrating the credibility and uncertainty of each evidence.Ultimately,initial evidences are amended and fused using Dempster’s rule of combination.The effectiveness of this approach in addressing the fusion of three typical conflict paradoxes is demonstrated by arithmetic exam-ples.Additionally,the proposed approach is applied to aerial tar-get recognition and iris dataset-based classification to validate its efficacy.Results indicate that the proposed approach can enhance the accuracy of target recognition and effectively address the issue of fusing conflicting evidences. 展开更多
关键词 Dempster-Shafer(D-S)evidence theory multi-source information fusion conflict measurement belief expo-nential divergence(BED) target recognition
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A density functional theory study of polarons on different TiO_(2) surfaces
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作者 SHI Zhiqun GONG Xueqing 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第12期1877-1888,I0011-I0013,共15页
Polarons are widely considered to play a crucial role in the charge transport and photocatalytic performance of materials,but the mechanisms of their formation and the underlying driving factors remain a matter of con... Polarons are widely considered to play a crucial role in the charge transport and photocatalytic performance of materials,but the mechanisms of their formation and the underlying driving factors remain a matter of controversy.This study delves into the formation of polarons in different crystalline forms of TiO_(2) and their connection with the materials'structure.By employing density functional theory calculations with on-site Coulomb interaction correction(DFT+U),we provide a detailed analysis of the electronic polarization behavior in the anatase and rutile forms of TiO_(2).We focus on the polarization properties of defect-induced and photoexcited excess electrons on various TiO_(2) surfaces.The results reveal that the defect electrons can form small polarons on the anatase TiO_(2)(101)surface,while on the rutile TiO_(2)(110)surface,both small and large polarons(hybrid-state polarons)are formed.Photoexcited electrons are capable of forming both small and large polarons on the surfaces of both crystal types.The analysis indicates that the differences in polaron distribution are primarily determined by the intrinsic properties of the crystals;the structural and symmetry differences between anatase and rutile TiO_(2) lead to the distinct polaron behaviors.Further investigation suggests that the polarization behavior of defect electrons is also related to the arrangement of electron orbitals around the Ti atoms,while the polarization of photoexcited electrons is mainly facilitated by the lattice distortions.These findings elucidate the formation mechanisms of different types of polarons and may contribute to understanding the performance of TiO_(2)in different fields. 展开更多
关键词 POLARON surface defect PHOTOEXCITATION TiO_(2) density functional theory
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Design of a Metasurface Antenna Based on Characteristic Mode Theory
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作者 HE Huan 《电讯技术》 北大核心 2024年第10期1561-1568,共8页
A novel metasurface antenna consisting of 5×5 rectangular patch elements is presented.Thestructure with and without the central element are both analyzed by the Characteristic Mode Theory(CMT).The developed mutua... A novel metasurface antenna consisting of 5×5 rectangular patch elements is presented.Thestructure with and without the central element are both analyzed by the Characteristic Mode Theory(CMT).The developed mutually orthogonal principal modes of the optimized periodic patch structure areexcited by a center-feed dipole.A differential feeding network is employed to realize impedance matching.Prototype with profile height of 0.07λ_(0)(λ_(0)is the wavelength in free space at the lowest operatingfrequency)is fabricated and assembled to verify the simulation results.The measured results show that thereflectance coefficient of proposed matesurface antenna is less than-10 dB in the whole operating bandrange from 4.2 GHz to 5.5 GHz,a relative bandwidth of 26.8%is achieved,and the maximummeasured realized gain is more than 9 dBi with a maximum radiation efficiency of 90%.The designprovides a guideline on the application of characteristic modes(CMs)to radiation problems. 展开更多
关键词 metasurface antenna characteristic mode theory dipole antenna realized gain
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A new method for evaluating the firing precision of multiple launch rocket system based on Bayesian theory
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作者 Yunfei Miao Guoping Wang Wei Tian 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第2期232-241,共10页
How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS consi... How to effectively evaluate the firing precision of weapon equipment at low cost is one of the core contents of improving the test level of weapon system.A new method to evaluate the firing precision of the MLRS considering the credibility of simulation system based on Bayesian theory is proposed in this paper.First of all,a comprehensive index system for the credibility of the simulation system of the firing precision of the MLRS is constructed combined with the group analytic hierarchy process.A modified method for determining the comprehensive weight of the index is established to improve the rationality of the index weight coefficients.The Bayesian posterior estimation formula of firing precision considering prior information is derived in the form of mixed prior distribution,and the rationality of prior information used in estimation model is discussed quantitatively.With the simulation tests,the different evaluation methods are compared to validate the effectiveness of the proposed method.Finally,the experimental results show that the effectiveness of estimation method for firing precision is improved by more than 25%. 展开更多
关键词 Multiple launch rocket system Bayesian theory Simulation credibility Mixed prior distribution Firing precision
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Assessing the range of blasting-induced cracks in the surrounding rock of deeply buried tunnels based on the unified strength theory
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作者 LI Liang CHEN Jia-jun +3 位作者 ZHAO Lian-heng HE Ke-pei HU Shi-hong LI Hua-long 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2341-2364,共24页
Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-in... Blasting-induced cracks in the rock surrounding deeply buried tunnels can result in water gushing and rock mass collapse,posing significant safety risks.However,previous theoretical studies on the range of blasting-induced cracks often ignore the impact of the in-situ stress,especially that of the intermediate principal stress.The particle displacement−crack radius relationship was established in this paper by utilizing the blasthole cavity expansion equation,and theoretical analytical formulas of the stress−displacement relationship and the crack radius were derived with unified strength theory to accurately assess the range of cracks in deep surrounding rock under a blasting load.Parameter analysis showed that the crushing zone size was positively correlated with in-situ stress,intermediate principal stress,and detonation pressure,whereas negatively correlated with Poisson ratio and decoupling coefficient.The dilatancy angle-crushing zone size relationship exhibited nonmonotonic behavior.The relationships in the crushing zone and the fracture zone exhibited opposite trends under the influence of only in-situ stress or intermediate principal stress.As the in-situ stress increased from 0 to 70 MPa,the rate of change in the crack range and the attenuation rate of the peak vibration velocity gradually slowed. 展开更多
关键词 deep drilling and blasting cracks in surrounding rock unified strength theory intermediate principle stress in-situ stress cavity expansion dilatancy characteristics
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电机气隙磁场调制统一理论研究进展与展望 被引量:4
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作者 程明 马钲洲 +2 位作者 花为 汪波 王政 《中国电机工程学报》 北大核心 2025年第4期1220-1236,I0001,共18页
电机气隙磁场调制统一理论于2017年由作者团队提出以来,便因在电机原理分析、性能计算和拓扑创新方面的优势,成为行业内的热点研究方向,经过多年的深入研究,在电机气隙磁场调制机理、气隙磁场调制数学表征方法等方面取得了多项原创性成... 电机气隙磁场调制统一理论于2017年由作者团队提出以来,便因在电机原理分析、性能计算和拓扑创新方面的优势,成为行业内的热点研究方向,经过多年的深入研究,在电机气隙磁场调制机理、气隙磁场调制数学表征方法等方面取得了多项原创性成果。该文从理论、技术和应用3个层面综述电机气隙磁场调制理论的最新研究进展,包括:提出磁感、磁容调制器,将磁场调制模态拓展为频率调制、幅值调制和相位调制,提出“基波+谐波”的多工作波电机设计思想等,厘清电机气隙磁场调制理论与传统电机理论的关系等。最后,对气隙磁场调制统一理论未来研究与发展方向进行展望。 展开更多
关键词 电机理论 磁场调制理论 谐波利用 多工作波电机 矢量磁路理论 磁感 电能
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“路径-目标”理论视角下公立医院发展型绩效考核实施的质性研究 被引量:3
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作者 魏万宏 胡佳奇 +2 位作者 周珂 陈艳红 侯梦园 《中国医院》 北大核心 2025年第4期1-6,共6页
目的:探讨公立医院发展型绩效考核的实施对组织发展的影响机制。方法:采用目的抽样方法,选取河南省5所三级甲等公立医院职能部门或医疗部门的医务人员共25人为研究对象。基于质性研究的扎根理论方法,以“路径-目标”理论为视角,使用Maxq... 目的:探讨公立医院发展型绩效考核的实施对组织发展的影响机制。方法:采用目的抽样方法,选取河南省5所三级甲等公立医院职能部门或医疗部门的医务人员共25人为研究对象。基于质性研究的扎根理论方法,以“路径-目标”理论为视角,使用Maxqda 2022软件分析访谈材料。结果:明确的目标导向和精细化管理是确保绩效考核有效执行的关键。高水平的组织情感承诺和公共服务动机显著提升员工内在动力,优化组织氛围,增强归属感和团队协作能力,从而推动绩效考核和组织目标的实现。结论:医院管理者应进一步优化领导策略,改善外部环境,细化任务结构,增强组织情感承诺和公共服务动机,确保政策执行的稳定性,推动公立医院绩效考核的持续改进和创新,助力实现高质量的医疗服务和组织发展目标。 展开更多
关键词 公立医院 “路径-目标”理论 绩效考核 组织发展 扎根理论
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中国和美乡村建设的理论与实践——乡村场景价值理论的视角 被引量:1
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作者 杨庆媛 王愈滋 +3 位作者 杨人豪 苏康传 王笛 孙朝辉 《西南大学学报(自然科学版)》 北大核心 2025年第4期1-15,共15页
目前,和美乡村建设的研究主要集中在政策分析和个案描述,亟需更加深入的理论研究。将场景理论与乡村多元价值理论有机结合,构建乡村场景价值理论,强调乡村多元价值在多种场景中的“生成—互动—反馈”逻辑,揭示各类价值在不同场景中的... 目前,和美乡村建设的研究主要集中在政策分析和个案描述,亟需更加深入的理论研究。将场景理论与乡村多元价值理论有机结合,构建乡村场景价值理论,强调乡村多元价值在多种场景中的“生成—互动—反馈”逻辑,揭示各类价值在不同场景中的显化过程;利用“乡村场景价值理论”分析框架,对成都市多利桃花源和重庆市武隆犀牛古寨乡村建设和发展进行案例分析,证实理论框架的适用性,进一步阐明差异化核心场景在乡村价值生成、互动和反馈中的引领作用。 展开更多
关键词 和美乡村 场景理论 乡村多元价值理论 乡村场景价值理论
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数字化转型赋能制造业新质生产力发展——基于资源基础理论与动态能力理论的实证研究 被引量:11
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作者 赵巧芝 郭紫晴 《工业技术经济》 北大核心 2025年第1期12-24,共13页
通过数字化转型引领新质生产力的发展,是数字经济赋能制造强国建设的重要课题。本文基于资源基础论与动态能力理论,剖析数字化转型驱动制造企业新质生产力发展的影响机理,为赋能新质生产力提供参考。结果发现:(1)数字化转型对制造企业... 通过数字化转型引领新质生产力的发展,是数字经济赋能制造强国建设的重要课题。本文基于资源基础论与动态能力理论,剖析数字化转型驱动制造企业新质生产力发展的影响机理,为赋能新质生产力提供参考。结果发现:(1)数字化转型对制造企业新质生产力的长期与短期影响存在差异,短期表现为提升整合、配置及运用资源能力,长期表现为增强其创新变革的感知、抓取与转化能力;(2)实证结果表明,数字化转型对新质生产力的影响显著为正。其中,短期影响的正向作用显著,长期影响不显著。不仅如此,市场竞争强度的正向调节作用不容忽视;(3)根据异质性效应结果,东部地区影响显著为正,中部与西部地区则较为微弱;国有企业的驱动效应明显高于非国有企业样本。研究结论为提升制造业新质生产力水平提供了新的赋能方向。 展开更多
关键词 数字化转型 制造业 新质生产力 资源基础论 动态能力理论 赋能机制 市场竞争强度 异质性效应
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TRIZ辅助红松虫害检测机器人概念设计
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作者 付敏 高风 +1 位作者 高泽飞 郝镒林 《机械设计与制造》 北大核心 2025年第8期106-111,共6页
针对红松虫害检测数据不准确、系统响应时间长、检测效果不理想的问题,这里基于TRIZ理论设计了一种采用图像识别检测、可蠕动攀爬树干的红松虫害检测机器人。通过需求分析,确定虫害检测机器人的动作流程和组成结构;应用最终理想解、技... 针对红松虫害检测数据不准确、系统响应时间长、检测效果不理想的问题,这里基于TRIZ理论设计了一种采用图像识别检测、可蠕动攀爬树干的红松虫害检测机器人。通过需求分析,确定虫害检测机器人的动作流程和组成结构;应用最终理想解、技术矛盾、物理矛盾、技术进化法则等TRIZ工具对移动机构、抱紧机构、检测机构进行创新设计,构建了红松虫害检测机器人的三维实体模型,应用ADAMS软件进行动态仿真,仿真结果表明攀爬运动过程符合设计要求。在产品概念设计阶段应用TRIZ理论,有利于产生高质量、多层级的概念解,提高产品设计效率。 展开更多
关键词 红松 虫害 检测机器人 蠕动 图像识别 概念设计 TRIZ(theory of Inventive Problem Solving)
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