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Resusci Anne(SimPad)在护理心肺复苏模拟教学中的应用 被引量:2
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作者 常丹丹 沈浩 +2 位作者 时文珠 邓曼丽 米卫东 《麻醉安全与质控》 2021年第3期173-176,共4页
目的探讨Resusci Anne(SimPad)在护理心肺复苏教学中的应用效果。方法选取2018-07/2019-12期间来我科实习且理论考试满分的大三女护生,统一观看操作视频后,随机分为Resusci Anne(SimPad)组(S组)和Resusci Anne组(R组),每组15人,S组和R... 目的探讨Resusci Anne(SimPad)在护理心肺复苏教学中的应用效果。方法选取2018-07/2019-12期间来我科实习且理论考试满分的大三女护生,统一观看操作视频后,随机分为Resusci Anne(SimPad)组(S组)和Resusci Anne组(R组),每组15人,S组和R组均在Resusci Anne模拟人上练习,S组使用SimPad反馈器,R组不使用SimPad反馈器。练习结束后,教师使用Simman3G模拟人考核2组学员心肺复苏,并对学员做考核后的调查问卷。记录并分析2组学员心肺复苏操作的整体分数、平均按压频率、平均按压深度、平均按压中断时间、平均通气量、操作信心、操作能力、教学满意度、课堂趣味性和再次参加模拟教学意愿。结果两组平均按压中断时间和平均通气量差异无统计学意义;S组平均胸外按压频率明显慢于R组,差异有统计学意义(P<0.05);S组平均按压深度明显高于R组,差异有统计学意义(P<0.05);S组整体分数明显高于R组,差异有统计学意义(P<0.05)。结论在心肺复苏模拟教学中,使用有反馈器SimPad的Resusci Anne模拟人练习,能够提高实习女护士心肺复苏质量及操作信心,也可激发实习女护士兴趣。 展开更多
关键词 心肺复苏 模拟教学 resusci Anne模拟人 Simman3G模拟人
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Restoration of space-variant blurred image based on motion-blurred target segmentation 被引量:4
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作者 Yuye Zhang Xuewei Wang Chunxin Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第2期191-196,共6页
In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on ima... In imaging on moving target, it is easy to get space- variant blurred image. In order to recover the image and gain recognizable target, an approach to recover the space-variant blurred image is presented based on image segmentation. Be- cause of motion blur's convolution process, the pixels of observed image's target and background will be displaced and piled up to produce two superposition regions. As a result, the neighbor- ing pixels in the superposition regions will have similar grey level change. According to the pixel's motion-blur character, the target's blurred edge of superposition region could be detected. Canny operator can be recurred to detect the target edge which parallels the motion blur direction. Then in the segmentation process, the whole target image which has the character of integral convolution between motion blur and real target image can be obtained. At last, the target image is restored by deconvolution algorithms with adding zeros. The restoration result indicates that the approach can effectively solve the kind of problem of space-variant motion blurred image restoration. 展开更多
关键词 image restoration space-variant blur image segmen- tation motion-blur.
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The Extreme Summer Precipitation over East China during 1982-2007 Simulated by the LASG/IAP Regional Climate Model 被引量:6
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作者 LIU Jing-Wei LI Bo +2 位作者 ZHOU Tian-Jun ZENG Xian-Feng FENG Lei 《Atmospheric and Oceanic Science Letters》 2012年第1期62-67,共6页
The extreme summer precipitation over East China during 1982-2007 was simulated using the LASG/IAP regional climate model CREM(the Climate version of a Regional Eta-coordinate Model).The results show that the probabil... The extreme summer precipitation over East China during 1982-2007 was simulated using the LASG/IAP regional climate model CREM(the Climate version of a Regional Eta-coordinate Model).The results show that the probability density functions(PDFs) of precipitation intensities are reasonably simulated,except that the PDFs of light and moderate rain are underestimated and that the PDFs of heavy rain are overestimated.The extreme precipitation amount(R95p) and the percent contribution of extreme precipitation to the total precipitation(R95pt) are also reasonably reproduced by the CREM.However,the R95p and R95pt over most of East China are generally overestimated,while the R95p along the coastal area of South China(SC) is underestimated.The bias of R95pt is consistent with the bias of precipitation intensity on wet days(SDII).The interannual variation for R95p anomalies(PC1) is well simulated,but that of R95pt anomalies(PC2) is poorly simulated.The skill of the model in simulating PC1(PC2) increases(decreases) from north to south.The bias of water vapor transport associated with the 95th percentile of summer daily precipitation(WVTr95) explains well the bias of the simulated extreme precipitation. 展开更多
关键词 regional climate simulation extreme precipi- tation East China CREM
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Rapid State Augmentation for Compressed EKF-Based Simultaneous Localization and Mapping 被引量:1
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作者 窦丽华 张海强 +1 位作者 陈杰 方浩 《Journal of Beijing Institute of Technology》 EI CAS 2009年第2期192-197,共6页
A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requi... A new method for speeding up the state augment operations involved in the compressed extended Kalman filter-based simultaneous localization and mapping (CEKF-SLAM) algorithm was proposed. State augment usually requires a fully-updated state eovariance so as to append the information of newly observed landmarks, thus computational volume increases quadratically with the number of landmarks in the whole map. It was proved that state augment can also be achieved by augmenting just one auxiliary coefficient ma- trix. This method can yield identical estimation results as those using EKF-SLAM algorithm, and computa- tional amount grows only linearly with number of increased landmarks in the local map. The efficiency of this quick state augment for CEKF-SLAM algorithm has been validated by a sophisticated simulation project. 展开更多
关键词 simultaneous localization and mapping (SLAM) extended Kalman filter state augment compu- tational volume
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Vehicle Representation and Classification of Surveillance Video Based on Sparse Learning 被引量:2
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作者 CHEN Xiangjun RUAN Yaduan +2 位作者 ZHANG Peng CHEN Qimei ZHANG Xinggan 《China Communications》 SCIE CSCD 2014年第A01期135-141,共7页
We cast vehicle recognition as problem of feature representation and classification, and introduce a sparse learning based framework for vehicle recognition and classification in this paper. After objects captured wit... We cast vehicle recognition as problem of feature representation and classification, and introduce a sparse learning based framework for vehicle recognition and classification in this paper. After objects captured with a GMM background subtraction program, images are labeled with vehicle type for dictionary learning and decompose the images with sparse coding (SC), a linear SVM trained with the SC feature for vehicle classification. A simple but efficient active learning stategy is adopted by adding the false positive samples into previous training set for dictionary and SVM model retraining. Compared with traditional feature representation and classification realized with SVM, SC method achieves dramatically improvement on classification accuracy and exhibits strong robustness. The work is also validated on real-world surveillance video. 展开更多
关键词 vehicle classification feature represen- tation sparse learning robustness and generalization
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Effects of a reagent’s rotational and vibrational excitations on reaction O(~3P) + H_2 (ν=0,3,j = 0,3,5,7,9,12,15) → OH+H
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作者 许增慧 宗福建 +3 位作者 韩博然 董少华 刘建强 计峰 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期187-195,共9页
To investigate the effect of a reagent's rotational and vibrational excitations on the stereo-dynamics of the reaction product, the title reaction is theoretically simulated using the quasi-classical trajectory (QCT... To investigate the effect of a reagent's rotational and vibrational excitations on the stereo-dynamics of the reaction product, the title reaction is theoretically simulated using the quasi-classical trajectory (QCT) method on the 3A~ and 3Aq potentiM energy surfaces (PESs). The reaction cross section is considered as the only scalar property in this work at four different collision energies. Furthermore the vector properties including two polarization-dependent differential cross sections (PDDCSs), the angular distributions of product' rotational momentum are discussed at one fixed collision energy. Effects of reagents' rotational excitation on the reaction do exist regularly. 展开更多
关键词 chemical stereo-dynamics quasi-classical trajectory calculation vector correlation ro- tational and vibrational excitations
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Ab initio Calculations of Electron-Impact Excitation Cross Sections for N_2 Molecule
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作者 信裕 丁洪斌 《Plasma Science and Technology》 SCIE EI CAS CSCD 2014年第2期104-109,共6页
One of the great difficulties in understanding nitrogen plasma elementary processes is the lack of an available database of the cross-sections of electron-impact excitations and radiations. Ab initio calculations of v... One of the great difficulties in understanding nitrogen plasma elementary processes is the lack of an available database of the cross-sections of electron-impact excitations and radiations. Ab initio calculations of vibrational excitation cross sections for electron collisions with nitrogen molecules in low-lying states using similarity function approach, such as a-a', a-w, B-B' and B-W transition systems, are reported here for the first time. In the meantime, the average excitation energies of neighboring levels of these systems have been calculated. In order to obtain the cross sections, accurate spectroscopic constants and transition dipole moments have been investigated. Potential energy curves and other electronic transition dipole moments for the low-lying states of N2 have been re-evaluated using complete active space self-consistent field (CASSCF) approach with aug-cc-pVqZ basis set. The calculated cross-sections could provide a database for studying the elementary processes and the properties in N2 plasma. 展开更多
关键词 N2 potential energy curves transition dipole moments electron-impact exci- tation cross sections
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Rationale for the potential use of mesenchymal stromal cells in liver transplantation 被引量:3
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作者 Morgan Vandermeulen Céline Grégoire +3 位作者 Alexandra Briquet Chantal Lechanteur Yves Beguin Olivier Detry 《World Journal of Gastroenterology》 SCIE CAS 2014年第44期16418-16432,共15页
Mesenchymal stromal cells (MSCs) are multipotent and self-renewing cells that reside essentially in the bone marrow as a non-hematopoietic cell population, but may also be isolated from the connective tissues of most ... Mesenchymal stromal cells (MSCs) are multipotent and self-renewing cells that reside essentially in the bone marrow as a non-hematopoietic cell population, but may also be isolated from the connective tissues of most organs. MSCs represent a heterogeneous population of adult, fibroblast-like cells characterized by their ability to differentiate into tissues of mesodermal lineages including adipocytes, chondrocytes and osteocytes. For several years now, MSCs have been evaluated for their in vivo and in vitro immunomodulatory and &#x02018;tissue reconstruction&#x02019; properties, which could make them interesting in various clinical settings, and particularly in organ transplantation. This paper aims to review current knowledge on the properties of MSCs and their use in pre-clinical and clinical studies in solid organ transplantation, and particularly in the field of liver transplantation. The first available clinical data seem to show that MSCs are safe to use, at least in the medium-term, but more time is needed to evaluate the potential adverse effects of long-term use. Many issues must be resolved on the correct use of MSCs. Intensive in vitro and pre-clinical research are the keys to a better understanding of the way that MSCs act, and to eventually lead to clinical success. 展开更多
关键词 Mesenchymal stem cells Organ transplantation COMPLICATION IMMUNOSUPPRESSION TOLERANCE
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Kraus operator solutions to a fermionic master equation describing a thermal bath and their matrix representation 被引量:2
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作者 孟祥国 王继锁 +1 位作者 范洪义 夏承魏 《Chinese Physics B》 SCIE EI CAS CSCD 2016年第4期42-46,共5页
We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix repr... We solve the fermionic master equation for a thermal bath to obtain its explicit Kraus operator solutions via the fermionic state approach. The normalization condition of the Kraus operators is proved. The matrix representation for these solutions is obtained, which is incongruous with the result in the book completed by Nielsen and Chuang [Quan- tum Computation and Quantum Information, Cambridge University Press, 2000]. As especial cases, we also present the Kraus operator solutions to master equations for describing the amplitude-decay model and the diffusion process at finite temperature. 展开更多
关键词 Kraus operator solution matrix representation thermal bath fermionic entangled state represen-tation
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Olfactory ensheathing cell transplantation improves sympathetic skin responses in chronic spinal cord injury 被引量:6
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作者 Zuncheng Zheng Guifeng Liu +1 位作者 Yuexia Chen Shugang Wei 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第30期2849-2855,共7页
Forty-three patients with chronic spinal cord injury for over 6 months were transplanted with bryonic olfactory ensheathing cells, 2-4 × 106, into multiple sites in the injured area under the sur-gical microscope... Forty-three patients with chronic spinal cord injury for over 6 months were transplanted with bryonic olfactory ensheathing cells, 2-4 × 106, into multiple sites in the injured area under the sur-gical microscope. The sympathetic skin response in patients was measured with an electromyo-graphy/evoked potential instrument 1 day before transplantation and 3-8 weeks after trans-tion. Spinal nerve function of patients was assessed using the American Spinal Injury Association impairment scale. The sympathetic skin response was elicited in 32 cases before olfactory en-sheathing celltransplantation, while it was observed in 34 cases after transplantation. tantly, sympathetic skin response latency decreased significantly and amplitude increased cantly after transplantation. Transplantation of olfactory ensheathing cells also improved American Spinal Injury Association scores for movement, pain and light touch. Our findings indicate that factory ensheathing celltransplantation improves motor, sensory and autonomic nerve functions in patients with chronic spinal cord injury. 展开更多
关键词 neural regeneration spinal cord injury clinical practice olfactory ensheathing cells cell transplan-tation olfactory ensheathing cell transplantation sympathetic skin response neurological function autonomic nerve PARALYSIS NEUROREGENERATION
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Huashan Hospital Clinical Laboratory receives accredi- tation from College of American Pathologists
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《Chinese Medical Journal》 SCIE CAS CSCD 2006年第11期952-952,共1页
Huashan Hospital Clinical Laboratory, Shanghai, China, has been awarded an accreditation by the Commission on Laboratory Accreditation of the College of American Pathologists (CAP), based on the results of a recent ... Huashan Hospital Clinical Laboratory, Shanghai, China, has been awarded an accreditation by the Commission on Laboratory Accreditation of the College of American Pathologists (CAP), based on the results of a recent on-site inspection. 展开更多
关键词 Huashan Hospital Clinical Laboratory receives accredi tation from College of American Pathologists
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Endogenous aspergillus endophthalmitis after kidney transplantation
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作者 Huan-Huan Cheng, Jin-Tang Xu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2011年第5期567-571,共5页
Endogenous aspergillus endophthalmitis(EAE) after kidney transplant is a rare but important clinical problem due to potentially devastating consequences. Early diagnosis of EAE, timely removal of affected vitreous by ... Endogenous aspergillus endophthalmitis(EAE) after kidney transplant is a rare but important clinical problem due to potentially devastating consequences. Early diagnosis of EAE, timely removal of affected vitreous by vitrectomy, proper anti-fungal treatment, all contributed to the successful control of the disease. Therapeutic success of EAE in post-transplant patients depends largely on prompt diagnosis. Definite diagnosis of EAE is based on positive culture results of vitreous specimen, while fundoscopy and B scan ultrasound may aid early diagnosis. In terms of anti-fungal medicine, amphotericin B has long been the first choice, but its systemic applicaiton has severe adverse reactions, especially for patients with impaired renal function. Herein, we report the treatment modality of EAE after kidney transplant with vitrectomy, systemic administration of micafungin plus voriconazole, topical application of fluconazol and amphotercin B. 展开更多
关键词 ASPERGILLUS ENDOPHTHALMITIS kidney transplan-tation amphotercin B MICAFUNGIN
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乳酸菌协同发酵玉米蛋白水解物工艺条件优化及其对抗氧化活性影响 被引量:1
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作者 丛珊滋 曹雨佳 +3 位作者 张欣欣 李冠龙 刘晓兰 胡楠 《食品研究与开发》 CAS 2024年第5期152-162,共11页
该文以玉米蛋白水解物为原料,以鼠李糖乳杆菌YY⁃15和发酵乳杆菌YY⁃16为发酵菌株,通过单因素试验和响应面试验优化发酵条件,并对发酵后玉米蛋白水解物的体外抗氧化能力和氨基酸含量进行分析评价。结果表明,两株乳杆菌协同发酵玉米蛋白水... 该文以玉米蛋白水解物为原料,以鼠李糖乳杆菌YY⁃15和发酵乳杆菌YY⁃16为发酵菌株,通过单因素试验和响应面试验优化发酵条件,并对发酵后玉米蛋白水解物的体外抗氧化能力和氨基酸含量进行分析评价。结果表明,两株乳杆菌协同发酵玉米蛋白水解物的最佳发酵工艺为菌种体积比3∶1,玉米蛋白水解物浓度20.50%,接种量4%,果葡糖浆添加量5%,发酵温度39.5℃,发酵时间24 h。在该条件下,发酵后玉米蛋白水解物的体外DPPH自由基、羟自由基和超氧阴离子自由基三者清除能力的IC50值分别为0.227、0.200、12.851 mg/mL,Fe^(2+)螯合能力的IC_(50)为1.856 mg/mL,与发酵前相比分别提高了50.65%、34.64%、6.41%、41.36%。 展开更多
关键词 玉米蛋白水解物 鼠李糖乳杆菌 发酵乳杆菌 协同发酵 抗氧化活性
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V型Transformer的遥感影像障碍物提取方法
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作者 邓飞 罗文 +2 位作者 蒋先艺 许银坡 王岩 《石油地球物理勘探》 EI CSCD 北大核心 2024年第4期745-754,共10页
遥感影像中的障碍物是地震采集观测系统变观的重要依据之一。传统的人工提取障碍物方法效率低,且易受人为因素影响,难以保证结果的一致性,不适用于复杂地表环境及数量庞大的障碍物。当前通用的卷积神经网络自动提取障碍物方法,由于卷积... 遥感影像中的障碍物是地震采集观测系统变观的重要依据之一。传统的人工提取障碍物方法效率低,且易受人为因素影响,难以保证结果的一致性,不适用于复杂地表环境及数量庞大的障碍物。当前通用的卷积神经网络自动提取障碍物方法,由于卷积核的尺寸受限,无法直接进行远距离的语义交互,也不能准确提取具有较大跨度且部分被遮蔽的障碍物(乡间道路、河流等)。为此,提出了基于V型全自注意力网络(MTNet)提取遥感影像障碍物的方法。首先,MTNet采用端到端的V型编码器—解码器结构,通过跳跃连接实现信息交互;其次,用具有远距离建模能力的Mix-Transformer模块取代传统卷积层,提取和重建更准确的障碍物多尺度特征;最后,用轻量的块扩展层取代转置卷积,实现上采样和图像分割,重建障碍物信息。实验结果表明,该网络分割障碍物的精度和速度显著优于现有方法,尤其在道路识别方面,优势更明显。 展开更多
关键词 观测系统变观 深度学习 障碍物提取 图像语义分割 Mix-Transformer
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基于快速康复理论的55A模式干预在老年肺鳞状细胞癌手术患者中的应用效果
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作者 段兰兰 韩培培 +1 位作者 申月月 刘帅 《癌症进展》 2024年第16期1770-1773,1797,共5页
目的探讨基于快速康复理论的5A模式干预在老年肺鳞状细胞癌患者中的应用效果。方法根据干预方法的不同将98例老年肺鳞状细胞癌手术患者分为对照组(n=46)和观察组(n=52),对照组患者采取常规干预,观察组患者在对照组的基础上采取基于快速... 目的探讨基于快速康复理论的5A模式干预在老年肺鳞状细胞癌患者中的应用效果。方法根据干预方法的不同将98例老年肺鳞状细胞癌手术患者分为对照组(n=46)和观察组(n=52),对照组患者采取常规干预,观察组患者在对照组的基础上采取基于快速康复理论的5A模式干预。比较两组患者的术后恢复指标、疲乏程度[Piper疲乏量表(PFS)]、自我护理能力[自我护理能力测定量表(ESCA)]、肺功能指标[用力肺活量(FVC)、通气时间、第1秒用力呼气容积(FEV_(1))]及术后并发症发生情况。结果观察组患者肛门排气时间、引流管留置时间、首次下床时间及住院时间均明显短于对照组,差异均有统计学意义(P﹤0.01)。干预后,两组患者PFS评分均低于本组干预前,ESCA评分均高于本组干预前,观察组患者PFS评分低于对照组,ESCA评分高于对照组,差异均有统计学意义(P﹤0.05)。干预后,两组患者FVC、FEV_(1)均高于本组干预前,通气时间均短于本组干预前,观察组患者FVC、FEV_(1)均高于对照组,通气时间短于对照组,差异均有统计学意义(P﹤0.05)。观察组患者的术后并发症总发生率低于对照组(P﹤0.05)。结论基于快速康复理论的5A模式干预应用于老年肺鳞状细胞癌手术患者,可促进患者术后康复,降低疲乏程度和术后并发症发生率,提高自我护理能力,改善肺功能。 展开更多
关键词 快速康复理论 5A模式干预 肺鳞状细胞癌 术后康复 疲乏程度 自我护理能力
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危险作业罪罪过形式的确定——过失危险犯理论的再思考
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作者 王磊 《浙江万里学院学报》 2024年第3期39-45,共7页
危险作业罪作为新增罪名,其主观罪过存在着过失说、故意说以及混合罪过说之争。危险作业罪罪过争议问题是过失危险犯理论争议问题在具体各罪上的表现,对过失危险犯理论的正本清源是解决危险作业罪罪过问题的必要条件。过失危险犯否定论... 危险作业罪作为新增罪名,其主观罪过存在着过失说、故意说以及混合罪过说之争。危险作业罪罪过争议问题是过失危险犯理论争议问题在具体各罪上的表现,对过失危险犯理论的正本清源是解决危险作业罪罪过问题的必要条件。过失危险犯否定论者所认为的过失危险犯无法律明文规定、有违结果过失原则、与司法实践相冲突以及无益于犯罪人的特殊预防等理由是存在可商之处的。在刑法中设立过失危险犯,既满足社会治理的需要而具有目正当性,也有助于规范司法实践而践行刑法的基本理念。在承认过失危险犯的基础上,无论是通过主观主义刑法解释还是客观主义刑法解释,都能得出危险作业罪主观过为过失的结论。 展开更多
关键词 危险作业罪 过失危险犯 过失 刑法解释
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华北油田油气密闭混输技术应用
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作者 牛忠晓 贾剑磊 +4 位作者 李响 胡太勇 邓明 谷胜群 魏红曼 《石油石化节能与计量》 CAS 2024年第9期7-11,共5页
华北油田第三采油厂所辖站场数量多,包括较多转油站和供热拉油站,多数站内保留着传统原油处理工艺,设备设施老化严重,生产成本较高,不易于管理。为最大程度地减少或降级部分站场,简化优化原油处理工艺流程,停用部分能耗较高的设备,开展... 华北油田第三采油厂所辖站场数量多,包括较多转油站和供热拉油站,多数站内保留着传统原油处理工艺,设备设施老化严重,生产成本较高,不易于管理。为最大程度地减少或降级部分站场,简化优化原油处理工艺流程,停用部分能耗较高的设备,开展油气密闭混输技术研究并进行现场应用。该技术的研究主要集中在油气混输装置,在两座站场应用的油气密闭混输装置成功解决了气相、液相共用一个泵腔结构给多相混输设备带来的技术难题;现场应用体现在两座站场实现越站外输,停运储油罐及部分原油处理设备。转油站应用油气密闭混输技术可在很大程度上简化工艺流程,实现站场降级,优化后,两个站年节省各类费用439.6万元,其经济效益和社会效益可观。 展开更多
关键词 原油处理 油气密闭混输 越站外输 站场降级
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内蒙古赤峰柴胡栏子金矿田遥感地质解译和蚀变信息提取与找矿预测 被引量:1
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作者 韩燿徽 王翠芝 +3 位作者 吴志杰 吕古贤 张宝林 张启鹏 《现代地质》 CAS CSCD 北大核心 2024年第4期1076-1091,共16页
内蒙古柴胡栏子金矿田位于赤峰—朝阳金成矿带的最西北侧,是我国重要的黄金产地,但其自然条件恶劣,遥感地质研究程度较低,对于最主要的控矿因素(地层、构造、岩浆岩)分布特征以及与本区金成矿相关的围岩蚀变信息研究相对较少,利用遥感... 内蒙古柴胡栏子金矿田位于赤峰—朝阳金成矿带的最西北侧,是我国重要的黄金产地,但其自然条件恶劣,遥感地质研究程度较低,对于最主要的控矿因素(地层、构造、岩浆岩)分布特征以及与本区金成矿相关的围岩蚀变信息研究相对较少,利用遥感技术对该矿田进行找矿勘查具有重要意义。本文利用Landsat 8和GF-2遥感影像,结合“主成分分析+最佳指数因子”的方法组合,对柴胡栏子金矿田进行遥感地质解译。根据蚀变矿物的波谱特征,设计去除干扰信息-异常信息提取-异常分级-异常信息处理的蚀变信息提取方案,对Landsat 8和Sentinel-2A遥感影像进行蚀变信息提取;在前人区域地质、矿田地质研究的基础上,依据蚀变信息特征,结合地质解译成果圈定3个找矿靶区。研究表明,利用多源遥感卫星影像对研究区进行地质解译与蚀变信息提取,基本能够满足辅助中比例尺找矿预测及地质综合调查的需要,并提升找矿效率。研究成果对柴胡栏子金矿田未来找矿勘查具有基础性指导意义。 展开更多
关键词 柴胡栏子金矿田 多源遥感卫星影像 遥感解译 蚀变信息提取 主成分分析 找矿预测
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发酵助剂配方优化对小麦秸秆厌氧消化产甲烷的研究
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作者 曹春晖 叶小梅 +5 位作者 刘洋 贾昭炎 王成成 杜静 孔祥平 奚永兰 《饲料工业》 CAS 北大核心 2024年第5期77-83,共7页
试验旨在研究不同种类及不同复配方式的添加剂对小麦秸秆厌氧消化(anaerobic diges⁃tion,AD)的影响。研究了四氧化三铁纳米颗粒(Fe_(3)O_(4)nanoparticles,NPS-Fe_(3)O_(4))、三氧化二铁纳米颗粒(Fe_(2)O_(3)nanoparticles,NPS-Fe_(2)O_... 试验旨在研究不同种类及不同复配方式的添加剂对小麦秸秆厌氧消化(anaerobic diges⁃tion,AD)的影响。研究了四氧化三铁纳米颗粒(Fe_(3)O_(4)nanoparticles,NPS-Fe_(3)O_(4))、三氧化二铁纳米颗粒(Fe_(2)O_(3)nanoparticles,NPS-Fe_(2)O_(3))、四氧化三铁(Fe_(3)O_(4))、三氧化二铁(Fe_(2)O_(3))、氯化亚铁(FeCl_(2))、血晶素(hemin)、皂苷(Ginsenoside Rg1,Rg1)七种外源添加剂在不同添加浓度及搭配方式对AD产甲烷的影响。结果表明:单独添加各发酵助剂均可显著提高AD的累计甲烷产量,混合添加后提升效果反而降低。其中单独添加100 mg/L Fe_(2)O_(3)的提升效果最好,累计甲烷产量达到207 mL/g,比空白组提高了86%。通过不同复配方式添加发酵助剂的试验结果显示,混合添加100 mg/L FeCl_(2)+1 mg/L hemin的提升效果最好,累计甲烷产量达到192 mL/g,比空白组高出了70%。试验所用的发酵助剂提高了小麦秸秆厌氧消化效率,为农业废弃物厌氧处理提供进一步技术支撑。 展开更多
关键词 厌氧消化 甲烷 发酵助剂 小麦秸秆 消化速率
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uBlock算法的低延迟一阶门限实现方法
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作者 姚富 陈华 范丽敏 《电子学报》 EI CAS CSCD 北大核心 2024年第4期1250-1259,共10页
目前已有文献给出了uBlock分组密码算法的侧信道防护方案,但是这些方案不仅延迟较高,难以适用于低延迟高吞吐场景,而且在毛刺探测模型下缺乏可证明安全性.针对这一问题,本文给出了在毛刺探测模型下具有可证明安全性的uBlock算法的低延... 目前已有文献给出了uBlock分组密码算法的侧信道防护方案,但是这些方案不仅延迟较高,难以适用于低延迟高吞吐场景,而且在毛刺探测模型下缺乏可证明安全性.针对这一问题,本文给出了在毛刺探测模型下具有可证明安全性的uBlock算法的低延迟门限实现方案.此外,我们引入了Changing of the Guards技术来避免防护方案在执行过程中需要额外随机数.对于防护方案的安全性,我们用自动化评估工具SILVER验证了S盒的毛刺探测安全性,并用泄露评估技术TVLA(Test Vector Leakage Assessment)验证了防护方案的整个电路的安全性.最后,我们用Design Compiler工具对防护方案的性能消耗情况进行了评估.评估结果显示,与序列化实现方式的uBlock防护方案相比,我们的防护方案的延迟能够减少约95%. 展开更多
关键词 密码芯片 uBlock算法 侧信道攻击与防护 掩码技术 门限实现 Changing of the Guards
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