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Non-Neural 3D Nasal Reconstruction:A Sparse Landmark Algorithmic Approach for Medical Applications
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作者 Nguyen Khac Toan Ho Nguyen Anh Tuan Nguyen Truong Thinh 《Computer Modeling in Engineering & Sciences》 2025年第5期1273-1295,共23页
This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D n... This paper presents a novel method for reconstructing a highly accurate 3D nose model of the human from 2D images and pre-marked landmarks based on algorithmic methods.The study focuses on the reconstruction of a 3D nose model tailored for applications in healthcare and cosmetic surgery.The approach leverages advanced image processing techniques,3D Morphable Models(3DMM),and deformation techniques to overcome the limita-tions of deep learning models,particularly addressing the interpretability issues commonly encountered in medical applications.The proposed method estimates the 3D coordinates of landmark points using a 3D structure estimation algorithm.Sub-landmarks are extracted through image processing techniques and interpolation.The initial surface is generated using a 3DMM,though its accuracy remains limited.To enhance precision,deformation techniques are applied,utilizing the coordinates of 76 identified landmarks and sub-landmarks.The resulting 3D nose model is constructed based on algorithmic methods and pre-marked landmarks.Evaluation of the 3D model is conducted by comparing landmark distances and shape similarity with expert-determined ground truth on 30 Vietnamese volunteers aged 18 to 47,all of whom were either preparing for or required nasal surgery.Experimental results demonstrate a strong agreement between the reconstructed 3D model and the ground truth.The method achieved a mean landmark distance error of 0.631 mm and a shape error of 1.738 mm,demonstrating its potential for medical applications. 展开更多
关键词 Nose reconstruction 3D reconstruction medical applications algorithmic reconstruction enhanced 3D model
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Rock discontinuity extraction from 3D point clouds using pointwise clustering algorithm
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作者 Xiaoyu Yi Wenxuan Wu +2 位作者 Wenkai Feng Yongjian Zhou Jiachen Zhao 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第7期4429-4444,共16页
Recognizing discontinuities within rock masses is a critical aspect of rock engineering.The development of remote sensing technologies has significantly enhanced the quality and quantity of the point clouds collected ... Recognizing discontinuities within rock masses is a critical aspect of rock engineering.The development of remote sensing technologies has significantly enhanced the quality and quantity of the point clouds collected from rock outcrops.In response,we propose a workflow that balances accuracy and efficiency to extract discontinuities from massive point clouds.The proposed method employs voxel filtering to downsample point clouds,constructs a point cloud topology using K-d trees,utilizes principal component analysis to calculate the point cloud normals,and employs the pointwise clustering(PWC)algorithm to extract discontinuities from rock outcrop point clouds.This method provides information on the location and orientation(dip direction and dip angle)of the discontinuities,and the modified whale optimization algorithm(MWOA)is utilized to identify major discontinuity sets and their average orientations.Performance evaluations based on three real cases demonstrate that the proposed method significantly reduces computational time costs without sacrificing accuracy.In particular,the method yields more reasonable extraction results for discontinuities with certain undulations.The presented approach offers a novel tool for efficiently extracting discontinuities from large-scale point clouds. 展开更多
关键词 Rock mass discontinuity 3D point clouds Pointwise clustering(PWC)algorithm Modified whale optimization algorithm(MWOA)
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3D numerical manifold method for crack propagation in rock materials using a local tracking algorithm
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作者 Boyi Su Tao Xu +3 位作者 Genhua Shi Michael J.Heap Xianyang Yu Guanglei Zhou 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第6期3449-3463,共15页
The modeling of crack growth in three-dimensional(3D)space poses significant challenges in rock mechanics due to the complex numerical computation involved in simulating crack propagation and interaction in rock mater... The modeling of crack growth in three-dimensional(3D)space poses significant challenges in rock mechanics due to the complex numerical computation involved in simulating crack propagation and interaction in rock materials.In this study,we present a novel approach that introduces a 3D numerical manifold method(3D-NMM)with a geometric kernel to enhance computational efficiency.Specifically,the maximum tensile stress criterion is adopted as a crack growth criterion to achieve strong discontinuous crack growth,and a local crack tracking algorithm and an angle correction technique are incorporated to address minor limitations of the algorithm in a 3D model.The implementation of the program is carried out in Python,using object-oriented programming in two independent modules:a calculation module and a crack module.Furthermore,we propose feasible improvements to enhance the performance of the algorithm.Finally,we demonstrate the feasibility and effectiveness of the enhanced algorithm in the 3D-NMM using four numerical examples.This study establishes the potential of the 3DNMM,combined with the local tracking algorithm,for accurately modeling 3D crack propagation in brittle rock materials. 展开更多
关键词 3D numerical manifold method(3D NMM) Crack propagation Local tracking algorithm Brittle materials
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A 3-Dimensional Cargo Loading Algorithm for the Conveyor-Type Loading System
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作者 Hyeonbin Jeong Young Tae Ryu +1 位作者 Byung Duk Song Sang-Duck Lee 《Computer Modeling in Engineering & Sciences》 2025年第3期2739-2769,共31页
This paper proposes a novel cargo loading algorithm applicable to automated conveyor-type loading systems.The algorithm offers improvements in computational efficiency and robustness by utilizing the concept of discre... This paper proposes a novel cargo loading algorithm applicable to automated conveyor-type loading systems.The algorithm offers improvements in computational efficiency and robustness by utilizing the concept of discrete derivatives and introducing logistics-related constraints.Optional consideration of the rotation of the cargoes was made to further enhance the optimality of the solutions,if possible to be physically implemented.Evaluation metrics were developed for accurate evaluation and enhancement of the algorithm’s ability to efficiently utilize the loading space and provide a high level of dynamic stability.Experimental results demonstrate the extensive robustness of the proposed algorithm to the diversity of cargoes present in Business-to-Consumer environments.This study contributes practical advancements in both cargo loading optimization and automation of the logistics industry,with potential applications in last-mile delivery services,warehousing,and supply chain management. 展开更多
关键词 3-dimensional loading automated loading system B2C logistics cargo loading algorithm conveyortype loading
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A novel heuristic pathfinding algorithm for 3D security modeling and vulnerability assessment
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作者 Jun Yang Yue-Ming Hong +2 位作者 Yu-Ming Lv Hao-Ming Ma Wen-Lin Wang 《Nuclear Science and Techniques》 2025年第5期152-166,共15页
Vulnerability assessment is a systematic process to identify security gaps in the design and evaluation of physical protection systems.Adversarial path planning is a widely used method for identifying potential vulner... Vulnerability assessment is a systematic process to identify security gaps in the design and evaluation of physical protection systems.Adversarial path planning is a widely used method for identifying potential vulnerabilities and threats to the security and resilience of critical infrastructures.However,achieving efficient path optimization in complex large-scale three-dimensional(3D)scenes remains a significant challenge for vulnerability assessment.This paper introduces a novel A^(*)-algorithmic framework for 3D security modeling and vulnerability assessment.Within this framework,the 3D facility models were first developed in 3ds Max and then incorporated into Unity for A^(*)heuristic pathfinding.The A^(*)-heuristic pathfinding algorithm was implemented with a geometric probability model to refine the detection and distance fields and achieve a rational approximation of the cost to reach the goal.An admissible heuristic is ensured by incorporating the minimum probability of detection(P_(D)^(min))and diagonal distance to estimate the heuristic function.The 3D A^(*)heuristic search was demonstrated using a hypothetical laboratory facility,where a comparison was also carried out between the A^(*)and Dijkstra algorithms for optimal path identification.Comparative results indicate that the proposed A^(*)-heuristic algorithm effectively identifies the most vulnerable adversarial pathfinding with high efficiency.Finally,the paper discusses hidden phenomena and open issues in efficient 3D pathfinding for security applications. 展开更多
关键词 Physical protection system 3D modeling and simulation Vulnerability assessment A^(*)Heuristic Pathfinding Dijkstra algorithm
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Flexible Monolithic 3D-Integrated Self-Powered Tactile Sensing Array Based on Holey MXene Paste
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作者 Mengjie Wang Chen Chen +9 位作者 Yuhang Zhang Yanan Ma Li Xu Dan‑Dan Wu Bowen Gao Aoyun Song Li Wen Yongfa Cheng Siliang Wang Yang Yue 《Nano-Micro Letters》 2026年第2期772-785,共14页
Flexible electronics face critical challenges in achieving monolithic three-dimensional(3D)integration,including material compatibility,structural stability,and scalable fabrication methods.Inspired by the tactile sen... Flexible electronics face critical challenges in achieving monolithic three-dimensional(3D)integration,including material compatibility,structural stability,and scalable fabrication methods.Inspired by the tactile sensing mechanism of the human skin,we have developed a flexible monolithic 3D-integrated tactile sensing system based on a holey MXene paste,where each vertical one-body unit simultaneously functions as a microsupercapacitor and pressure sensor.The in-plane mesopores of MXene significantly improve ion accessibility,mitigate the self-stacking of nanosheets,and allow the holey MXene to multifunctionally act as a sensing material,an active electrode,and a conductive interconnect,thus drastically reducing the interface mismatch and enhancing the mechanical robustness.Furthermore,we fabricate a large-scale device using a blade-coating and stamping method,which demonstrates excellent mechanical flexibility,low-power consumption,rapid response,and stable long-term operation.As a proof-of-concept application,we integrate our sensing array into a smart access control system,leveraging deep learning to accurately identify users based on their unique pressing behaviors.This study provides a promising approach for designing highly integrated,intelligent,and flexible electronic systems for advanced human-computer interactions and personalized electronics. 展开更多
关键词 Holey MXene Microsupercapacitor Tactile sensor Monolithic 3D integration Deep learning algorithm
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AKT抑制剂MK-2206对卵巢癌SKOV3细胞增殖凋亡的影响 被引量:1
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作者 郭红艳 张微 +1 位作者 黄玉琴 习红丽 《临床和实验医学杂志》 2017年第12期1181-1184,共4页
目的探讨MK-2206对卵巢癌SKOV3细胞增殖凋亡的影响及其作用机制。方法 MTT法检测MK-2206和顺铂单药及联合用药对SKOV3细胞增殖的影响,并计算半抑制浓度(IC50);FCM法检测MK-2206和顺铂单药及联合用药对SKOV3细胞凋亡的影响;Western-Blot... 目的探讨MK-2206对卵巢癌SKOV3细胞增殖凋亡的影响及其作用机制。方法 MTT法检测MK-2206和顺铂单药及联合用药对SKOV3细胞增殖的影响,并计算半抑制浓度(IC50);FCM法检测MK-2206和顺铂单药及联合用药对SKOV3细胞凋亡的影响;Western-Blot法检测各组丝苏氨酸蛋白激酶(AKT)、雷帕霉素靶体蛋白(m TOR)及核糖体S6蛋白激酶(70S6K)蛋白的表达情况。结果 MK-2206和顺铂两单药均可抑制SKOV3的增殖,各浓度组具有统计学差异(P<0.05),联合用药时可显著降低顺铂半抑制浓度(P<0.05);同时两单药组可促进SKOV3细胞凋亡(P<0.05),联合用药时凋亡作用更显著(P<0.05);MK-2206和顺铂对SKOV3细胞中AKT、m-TOR及70S6K表达无明显影响,但可抑制p-AKT、p-m TOR及p-70S6K表达水平(P<0.05)。结论 MK-2206可抑制SKOV3细胞的增殖,促进其凋亡,并可增强SKOV3细胞对顺铂敏感性,其可能与抑制AKT、m TOR及70S6K磷酸化水平有关。 展开更多
关键词 卵巢癌 mk-2206 顺铂 SKOV3
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MK-801对新生大鼠脑缺氧缺血后Caspase-3激活及其对凋亡的影响 被引量:3
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作者 朱长连 王小阳 《中国当代儿科杂志》 CAS CSCD 2001年第3期236-238,共3页
目的 探讨N 甲基 D 天冬氨酸 (NMDA)受体拮抗剂MK 80 1对新生大鼠缺氧缺血 (HI)后半胱天冬酶 3(Caspase 3)激活及凋亡的影响。 方法  7日龄新生大鼠在HI后即刻给予腹腔注射MK 80 10 .5mg/kg ,在HI后 2 4h取脑制作脑组织连续切片进... 目的 探讨N 甲基 D 天冬氨酸 (NMDA)受体拮抗剂MK 80 1对新生大鼠缺氧缺血 (HI)后半胱天冬酶 3(Caspase 3)激活及凋亡的影响。 方法  7日龄新生大鼠在HI后即刻给予腹腔注射MK 80 10 .5mg/kg ,在HI后 2 4h取脑制作脑组织连续切片进行微管相关蛋白 2 (MAP 2 ) ,Caspase 3免疫组化染色及发夹寡核苷酸探针(HairpinProbe ,HPP)原位杂交 ,计算脑损伤面积及Caspase 3,HPP阳性细胞数。 结果 ①MK 80 1干预组脑损伤面积为 (2 3± 5 ) % ,较生理盐水对照组 (5 2± 12 ) %明显降低 ,P <0 .0 1;②MK 80 1干预组Caspase 3及HPP阳性细胞数 (6 5± 8) /高倍视野 ,(6 1.6± 11.5 ) /高倍视野 ,与对照组 (4 0± 6 .7) /高倍视野 ,(12 .6± 5 .2 ) /高倍视野相比均明显减少 ,其中HPP阳性细胞数减少比Caspase 3阳性细胞数减少更明显。 结论 MK 80 1能明显抑制Caspase 3的激活 ,减少神经元的凋亡 ,减轻缺氧缺血性脑损伤 (HIBD)的程度。 展开更多
关键词 半胱天冬酶-3 NMDA受体 mk-801 发夹探针 新生大鼠 缺氧缺血性脑病 细胞凋亡
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MK-801对大鼠脊髓损伤后Caspase-3、HSP27表达的影响 被引量:1
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作者 李仁斌 郑忠 林焱斌 《福建医药杂志》 CAS 2012年第5期36-39,共4页
目的探讨大鼠脊髓损伤后应用兴奋性氨基酸受体非竞争性拮抗剂地卓西平马来酸盐(MK-801)对热休克蛋白27(HSP27)、半胱氨酸蛋白酶3(Caspase-3)表达及细胞凋亡的影响。方法 20只SD大鼠平均分为2组,采用Al-len's法造成SD大鼠脊髓损伤模... 目的探讨大鼠脊髓损伤后应用兴奋性氨基酸受体非竞争性拮抗剂地卓西平马来酸盐(MK-801)对热休克蛋白27(HSP27)、半胱氨酸蛋白酶3(Caspase-3)表达及细胞凋亡的影响。方法 20只SD大鼠平均分为2组,采用Al-len's法造成SD大鼠脊髓损伤模型,分别给予MK-801及生理盐水治疗,24h后取材,用免疫组化染色检测Caspase-3阳性细胞及HSP27阳性细胞,用流式细胞学检测细胞凋亡。结果两组均发现Caspase-3、HSP27表达及凋亡细胞,损伤组Caspase-3表达及神经细胞凋亡指数均高于MK-801组(P<0.01),而HSP27表达MK-801组高于损伤组(P<0.01)。结论脊髓损伤后,MK-801能上调HSP27的表达,抑制Caspase-3表达及神经细胞凋亡。 展开更多
关键词 脊髓损伤 mk-801 CASPASE-3 HSP27 细胞凋亡
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局灶性脑缺血大鼠体内与体外结合[~3H]MK-801放射自显影的差别和意义
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作者 张忱 孟书聪 +1 位作者 徐亚萍 程兰英 《中日友好医院学报》 2001年第5期279-282,共4页
目的 :比较体内与体外两种结合 [3H]MK 80 1的方式放射自显影在反映局灶性脑缺血大鼠脑内N 甲基 D 门冬氨酸 (NMDA)受体状态上的差别和意义。方法 :线栓法阻塞大鼠右侧大脑中动脉 ,制成局灶性脑缺血模型。以 [3H]MK 80 1为配基 ,分别... 目的 :比较体内与体外两种结合 [3H]MK 80 1的方式放射自显影在反映局灶性脑缺血大鼠脑内N 甲基 D 门冬氨酸 (NMDA)受体状态上的差别和意义。方法 :线栓法阻塞大鼠右侧大脑中动脉 ,制成局灶性脑缺血模型。以 [3H]MK 80 1为配基 ,分别进行体内与体外受体结合实验 ,然后做放射自显影。结果 :体内结合实验中 ,缺血 1h、2h、4h组缺血侧损伤区纹状体、皮层 [3H]MK 80 1结合位点密度显著高于非缺血侧 (P <0 .0 5 )。体外结合实验中 ,缺血侧半脑 [3H]MK 80 1结合位点分布与非缺血侧无显著性差别 (P >0 .0 5 )。结论 :体内受体结合实验可反映局灶性脑缺血大鼠脑内NMDA受体活性的变化 ,体外受体结合实验仅反映脑内存在的受体的总数量。 展开更多
关键词 放射自显影 局灶性脑缺血 NMDA受体 [^3H]mk-801
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MK-801对大鼠脊髓损伤后细胞凋亡及Caspase-3、C-fos的影响
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作者 马千里 徐杰 《福建医药杂志》 CAS 2011年第1期63-65,共3页
目的探讨MK-801对急性损伤后脊髓细胞凋亡的影响。方法 30只清洁级SD大鼠随机分为假手术(Sham)组、脊髓损伤(SCI)组和MK-80l组,每组10只。假手术组仅作椎板切除,其他两组使用Allen s打击法建立脊髓损伤模型,伤后0.5 h,脊髓损伤组腹腔注... 目的探讨MK-801对急性损伤后脊髓细胞凋亡的影响。方法 30只清洁级SD大鼠随机分为假手术(Sham)组、脊髓损伤(SCI)组和MK-80l组,每组10只。假手术组仅作椎板切除,其他两组使用Allen s打击法建立脊髓损伤模型,伤后0.5 h,脊髓损伤组腹腔注射5 ml/kg生理盐水;MK-801组腹腔注射MK-801 5 mg/kg;假手术组不予处理。24 h后取出T10节段脊髓组织分别进行原位末端标记法(TUNEL)细胞凋亡监测、Caspase-3和C-fos蛋白免疫组织化学染色,观察TUNEL阳性细胞和Caspase-3、C-fos蛋白免疫反应的结果。结果伤后24 h,经t检验得出用Tunel,Caspase-3,C-fos三种方法测试脊髓损伤组阳性率都大于MK-80l组,Caspase-3蛋白、Fos蛋白与细胞凋亡存在相关性。结论急性脊髓损伤可刺激Caspase-3、C-fos基因的异常表达,这两者与细胞凋亡存在相关性,MK-801能够抑制这两者的异常表达,减少神经细胞的凋亡,能够保护神经元。 展开更多
关键词 脊髓损伤 凋亡 mk-801 C-FOS CASPASE-3
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Novel registration algorithm for 3-D images captured from multiple views of object surface
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作者 衡伟 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期411-413,共3页
A novel algorithm of 3-D surface image registration is proposed. It makes use of the array information of 3-D points and takes vector/vertex-like features as the basis of the matching. That array information of 3-D po... A novel algorithm of 3-D surface image registration is proposed. It makes use of the array information of 3-D points and takes vector/vertex-like features as the basis of the matching. That array information of 3-D points can be easily obtained when capturing original 3-D images. The iterative least-mean-squared (LMS) algorithm is applied to optimizing adaptively the transformation matrix parameters. These can effectively improve the registration performance and hurry up the matching process. Experimental results show that it can reach a good subjective impression on aligned 3-D images. Although the algorithm focuses primarily on the human head model, it can also be used for other objects with small modifications. 展开更多
关键词 image alignment 3-D image 3-D capture image registration iterative least-mean-squared algorithm
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MK-2206阻断PI3K/AKT通路对骨肉瘤细胞MG63增殖及侵袭性的影响 被引量:2
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作者 何德喜 童岚 +3 位作者 何汝畅 李晓琴 潘海峰 靳阳 《中国实验诊断学》 2015年第8期1254-1256,共3页
骨肉瘤(Osteosarcoma)也称成骨肉瘤,是常见的骨原发性恶性肿瘤,具有恶性程度高、侵袭性强、易复发转移等特点[1]。随着新辅助化疗、手术、术后化疗的开展,骨肉瘤5年生存率提高到近80%,但仍有半数以上的患者死于骨肉瘤的转移和复发[2]... 骨肉瘤(Osteosarcoma)也称成骨肉瘤,是常见的骨原发性恶性肿瘤,具有恶性程度高、侵袭性强、易复发转移等特点[1]。随着新辅助化疗、手术、术后化疗的开展,骨肉瘤5年生存率提高到近80%,但仍有半数以上的患者死于骨肉瘤的转移和复发[2]。有效控制骨肉瘤细胞的转移对延长患者生存期有着深远意义。PI3K/AKT细胞信号转导通路在肿瘤的发生、增殖、迁移、耐药等生物过程中发挥着重要作用。 展开更多
关键词 骨肉瘤细胞 MG63 mk-2206 PI3K/AKT 成骨肉瘤 原发性恶性肿瘤 新辅助化疗 侵袭性 细胞生长 下游基因
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毕赤酵母Gpn12异戊烯基转移酶NovQ催化合成MK-3
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作者 吴锡华 李哲敏 +8 位作者 刘会 王鹏 王丽 方雪 孙小雯 倪文枫 杨强 郑之明 赵根海 《生物工程学报》 CAS CSCD 北大核心 2018年第1期140-148,共9页
对异戊烯基转移酶NovQ在毕赤酵母Gpn12异源表达过程中诱导剂甲醇添加量进行了探究,并以毕赤酵母Gpn12全细胞为酶源,以甲萘醌、异戊烯醇为前体,催化合成维生素K2(MK-3)。每24 h添加2%甲醇时,NovQ表达量提高约36%。考察摇瓶中初始pH、温... 对异戊烯基转移酶NovQ在毕赤酵母Gpn12异源表达过程中诱导剂甲醇添加量进行了探究,并以毕赤酵母Gpn12全细胞为酶源,以甲萘醌、异戊烯醇为前体,催化合成维生素K2(MK-3)。每24 h添加2%甲醇时,NovQ表达量提高约36%。考察摇瓶中初始pH、温度、甲醇添加量、前体(甲萘醌、异戊烯醇)添加量、催化时间、十六烷基三甲基溴化铵(CTAB)添加量等7个因素对Gpn12全细胞催化合成MK-3的影响,发现催化温度、甲萘醌添加量、催化时间影响显著,对3个显著因素进行响应面优化得出催化条件为:催化温度31.56℃,甲萘醌添加量295.54 mg/L,催化时间15.87 h,优化后的摇瓶MK-3产量达到98.47 mg/L,与响应面预测结果一致,较优化前对照组提高了35%。在30 L发酵罐进行生物催化实验,催化时间24 h,细胞催化剂浓度220 g(干重)/L,MK-3产量达到189.67 mg/L。该方法为Gpn12规模化生产MK-3奠定了一定的基础。 展开更多
关键词 mk-3 毕赤酵母 全细胞催化 优化
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The parallel 3D magnetotelluric forward modeling algorithm 被引量:28
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作者 Tan Handong Tong Tuo Lin Changhong 《Applied Geophysics》 SCIE CSCD 2006年第4期197-202,共6页
The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the dat... The workload of the 3D magnetotelluric forward modeling algorithm is so large that the traditional serial algorithm costs an extremely large compute time. However, the 3D forward modeling algorithm can process the data in the frequency domain, which is very suitable for parallel computation. With the advantage of MPI and based on an analysis of the flow of the 3D magnetotelluric serial forward algorithm, we suggest the idea of parallel computation and apply it. Three theoretical models are tested and the execution efficiency is compared in different situations. The results indicate that the parallel 3D forward modeling computation is correct and the efficiency is greatly improved. This method is suitable for large size geophysical computations. 展开更多
关键词 Magnetotelluric 3D forward modeling MPI parallel programming design 3D staggered-grid finite difference method parallel algorithm.
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Unfolding analysis of LaBr3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration 被引量:12
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作者 Rui Shi Xian-Guo Tuo +4 位作者 Huai-Liang Li Yang-Yang Xu Fan-Rong Shi Jian-Bo Yang Yong Luo 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第1期23-31,共9页
With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study... With respect to the gamma spectrum, the energy resolution improves with increase in energy. The counts of full energy peak change with energy, and this approximately complies with the Gaussian distribution. This study mainly examines a method to deconvolve the LaBr_3:Ce gamma spectrum with a detector response matrix constructing algorithm based on energy resolution calibration.In the algorithm, the full width at half maximum(FWHM)of full energy peak was calculated by the cubic spline interpolation algorithm and calibrated by a square root of a quadratic function that changes with the energy. Additionally, the detector response matrix was constructed to deconvolve the gamma spectrum. Furthermore, an improved SNIP algorithm was proposed to eliminate the background. In the experiment, several independent peaks of ^(152)Eu,^(137)Cs, and ^(60)Co sources were detected by a LaBr_3:Ce scintillator that were selected to calibrate the energy resolution. The Boosted Gold algorithm was applied to deconvolve the gamma spectrum. The results showed that the peak position difference between the experiment and the deconvolution was within ± 2 channels and the relative error of peak area was approximately within 0.96–6.74%. Finally, a ^(133) Ba spectrum was deconvolved to verify the efficiency and accuracy of the algorithm in unfolding the overlapped peaks. 展开更多
关键词 Detector response MATRIX Energy resolution CALIBRATION LaBr3:Ce scintillator SNIP background elimination Boosted Gold DECONVOLUTION algorithm
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MK-3算法S盒硬件优化实现
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作者 李艳俊 张伟国 葛耀东 《微电子学与计算机》 2022年第10期17-25,共9页
认证加密算法是一种对称密钥加密方案.在加密过程中提供机密和数据完整性.MK-3算法是一种基于简化双工海绵结构的认证加密算法,它支持私人定制.并且MK-3算法是第一个使用16比特S盒的算法.该算法使用的S盒采用有限域上的乘法逆元结合仿... 认证加密算法是一种对称密钥加密方案.在加密过程中提供机密和数据完整性.MK-3算法是一种基于简化双工海绵结构的认证加密算法,它支持私人定制.并且MK-3算法是第一个使用16比特S盒的算法.该算法使用的S盒采用有限域上的乘法逆元结合仿射变换来构造.这种设计在保证代数安全性的同时,还可以通过有限域上的同构映射变换来降低硬件实现资源.目前MK-3算法S盒硬件的实现方案仍有较大的改进空间.本文的方案利用多项式基构造有限域将GF(2^(16))上的求逆运算转换到复合域GF((28)2)中,方案搜索并评估了两个域转换的线性布尔函数,其中包含16个仿射等价的同构矩阵.在此基础上还给出了复合域GF((28)2)中基于不可约多项式的乘法运算、求逆运算和平方乘运算的实现结果.此方案采用3种最基础的逻辑门:与门、异或门、非门.并适应所有门电路工艺.相对于目前最优的MK-3算法S盒硬件实现,本文的方案至少减少58.3%的电路面积.从FPGA仿真角度讲,本文的方案至少减少47.5%的查表资源. 展开更多
关键词 认证加密 mk-3算法 多项式基 16比特S盒 有限域
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Efficient algorithm for 3D bimodulus structures 被引量:6
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作者 Qinxue Pan Jianlong Zheng Pihua Wen 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2020年第1期143-159,共17页
The bimodulus material is a classical model to describe the elastic behavior of materials with tension-compression asymmetry.Due to the inherently nonlinear properties of bimodular materials,traditional iteration meth... The bimodulus material is a classical model to describe the elastic behavior of materials with tension-compression asymmetry.Due to the inherently nonlinear properties of bimodular materials,traditional iteration methods suffer from low convergence efficiency and poor adaptability for large-scale structures in engineering.In this paper,a novel 3D algorithm is established by complementing the three shear moduli of the constitutive equation in principal stress coordinates.In contrast to the existing 3D shear modulus constructed based on experience,in this paper the shear modulus is derived theoretically through a limit process.Then,a theoretically self-consistent complemented algorithm is established and implemented in ABAQUS via UMAT;its good stability and convergence efficiency are verified by using benchmark examples.Numerical analysis shows that the calculation error for bimodulus structures using the traditional linear elastic theory is large,which is not in line with reality. 展开更多
关键词 Elastic theory Bimodulus material 3D complemented algorithm Finite element method Generalized elastic law General 3D shear modulus
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Optimization algorithm for rapid 3D gravity inversion 被引量:2
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作者 Jing Lei Yao Chang-Li +3 位作者 Yang Ya-Bin Xu Meng-Long Zhang Guang-Zhi Ji Ruo-Ye 《Applied Geophysics》 SCIE CSCD 2019年第4期507-518,561,共13页
The practical application of 3D inversion of gravity data requires a lot of computation time and storage space.To solve this problem,we present an integrated optimization algorithm with the following components:(1)tar... The practical application of 3D inversion of gravity data requires a lot of computation time and storage space.To solve this problem,we present an integrated optimization algorithm with the following components:(1)targeting high accuracy in the space domain and fast computation in the wavenumber domain,we design a fast 3D forward algorithm with high precision;and(2)taking advantage of the symmetry of the inversion matrix,the main calculation in gravity conjugate gradient inversion is decomposed into two forward calculations,thus optimizing the computational efficiency of 3D gravity inversion.We verify the calculation accuracy and efficiency of the optimization algorithm by testing various grid-number models through numerical simulation experiments. 展开更多
关键词 GRAVITY 3D inversion optimization algorithm high efficiency massive data
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ω-3PUFAs Prevent MK-801-induced Cognitive Impairment in Schizophrenic Rats via the CREB/BDNF/TrkB Pathway 被引量:12
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作者 房茂胜 李行 +6 位作者 钱红 曾宽 叶萌 周勇杰 李辉 王小川 李毅 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第4期491-495,共5页
This study was to determine the protective effect of ω-3 polyunsaturated fatty acids(ω-3PUFAs) on MK-801-induced cognitive impairment in schizophrenia(SZ) rats and the underlying mechanism. A rat model of schizo... This study was to determine the protective effect of ω-3 polyunsaturated fatty acids(ω-3PUFAs) on MK-801-induced cognitive impairment in schizophrenia(SZ) rats and the underlying mechanism. A rat model of schizophrenia was induced by MK-801. The cognitive function of rats was assessed using a Morris water maze. The number of hippocampal neurons was measured by Nissl staining. The expression of CREB, p-CREB, BDNF, TrkB, p-TrkB, AKT, p-AKT, ERK, and p-ERK in the hippocampus of rats was detected by Western blotting. The results showed that ω-3PUFAs attenuated MK-801-induced cognitive impairment and hippocampal neurons loss, reversed the injury of the CREB/BDNF/TrkB pathway induced by MK-801, and antagonized MK-801-induced down-regulation of p-AKT and p-ERK in the hippocampus of rats. In conclusion, ω-3PUFAs enhances the CREB/BDNF/TrkB pathway by activating ERK and AKT, thereby increasing the synaptic plasticity and decreasing neuron loss, and antagonizing MK-801-induced cognitive impairment in schizophrenic rats. 展开更多
关键词 schizophrenia mk-801 ω-3 polyunsaturated fatty acids cognition impairment CREB/BDNF/TrkB pathway
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