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Hybrid neural state machine for neural network

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Science China(Information Sciences) 2021年第3期64卷 136-148页

作者： lei tian Zhenzhi WU Shuang WU Luping SHI Department of Precision Instrument Center for Brain-Inspired Computing Research(CBICR)Beijing Innovation Center for Future Chip Tsinghua University

The integration of computer-science-oriented and neuroscience-oriented approaches is believed to be a promising way for the development of artificial general intelligence(AGI). Recently, a hybrid tianjic chip that integrates both approaches has been reported, providing a general platform to facilitate the research of AGI. The control algorithm for handling various neural networks is the key to this platform; however, it is still primitive. In this work, we propose a hybrid neural state machine(H-NSM) framework that can efficiently cooperate with artificial neural networks and spiking neural networks and control the workflows to accomplish complex tasks. The H-NSM receives input from different types of networks, makes decisions according to the fusing of various information, and sends control signals to the sub-network or actuator. The H-NSM can be trained to adapt to context-aware tasks or sequential tasks, thereby improving system robustness. The training algorithm works correctly even if only 50% of the forced state information is provided. It achieved performance comparable to the optimum algorithm on the Tower of Hanoi task and achieved multiple tasks control on a self-driving bicycle. After only 50 training epochs, the transfer accuracy reaches 100% in the test case. It proves that H-NSM has the potential to advance control logic for hybrid systems, paving the way for designing complex intelligent systems and facilitating the research towards AGI.

关键词： hybrid neural state machine ANNs SNNs supervised learning context-aware task sequential task

Feedbacks between vegetation restoration and local precipitation over the Loess Plateau in China

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Science China Earth Sciences 2021年第6期64卷 920-931页

作者： Baoqing ZHANG lei tian Xining ZHAO Pute WU Key Laboratory of Western China’s Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou730000China Institute of Green Development for the Yellow River Drainage Basin Lanzhou UniversityLanzhou730000China Institute of Soil and Water Conservation Northwest A&F UniversityYangling712100China

The implementation of large-scale vegetation restoration over the Chinese Loess Plateau has achieved clear improvements in vegetation fraction,as evidenced by large areas of slopes and plains being restored to grassland or ***,such large-scale vegetation restoration has altered land-atmosphere exchanges of water and energy,as the land surface characteristics have *** variations could affect regional climate,especially local *** evaluating this feedback is an important scientific question in *** study constructs a coupled land-atmosphere model incorporating vegetation dynamics,and analyzes the spatio-temporal changes of different land use types and land surface parameters over the Loess *** considering the impacts of vegetation restoration on the water-energy cycle and on land-atmosphere interactions,we quantified the feedback effect of vegetation restoration on local precipitation across the Loess Plateau,and discussed the important underlying *** achieve a quantitative evaluation,we designed two simulation experiments,comprising a real scenario with vegetation restoration and a hypothetical scenario without vegetation *** enabled a comparison and analysis of the net impact of vegetation restoration on local *** results show that vegetation restoration had a positive effect on local precipitation over the Loess *** show that precipitation on the Loess Plateau increased significantly,at a rate of 7.84 mm yr^(-2),from 2000 to *** simulations show that the contribution of large-scale vegetation restoration to the precipitation increase was about 37.4%,while external atmospheric circulation changes beyond the Loess Plateau contributed the other 62.6%.The average annual precipitation under the vegetation restoration scenario over the Loess Plateau was 12.4%higher than that under the scenario without vegetation *** above research re

关键词： Coupled land-atmosphere modeling Vegetation restoration Water balance Hydrometeorology Ecohydrology

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斜锚短桩基础受力特性与控制因素研究

地下空间与工程学报 2024年第1期20卷 181-189页

作者：田雷谢强张逸青秦培原向城名国网经济技术研究院有限公司北京102209 重庆大学土木工程学院重庆400045 库区环境地质灾害防治国家地方联合工程研究中心(重庆) 重庆400045 国网重庆市电力公司经济技术研究院重庆401121 国核电力规划设计研究院重庆有限公司重庆401121

我国西南山区地形陡峭,存在着大量覆盖层薄、下覆基岩工程性状较好但开挖难度大的复合地层,不利于输电铁塔基础建设。针对该问题,采用斜锚短柱基础作为输电铁塔基础,该基础可以在减小开挖深度、降低施工难度的同时充分利用基岩的承载性... 详细信息

我国西南山区地形陡峭,存在着大量覆盖层薄、下覆基岩工程性状较好但开挖难度大的复合地层,不利于输电铁塔基础建设。针对该问题,采用斜锚短柱基础作为输电铁塔基础,该基础可以在减小开挖深度、降低施工难度的同时充分利用基岩的承载性能。为了探究斜锚短桩基础受力特性与主要控制因素,运用FLAC3D建立数值模型,探讨了锚杆锚筋直径和锚杆角度对斜锚短桩基础的抗拔承载特性影响。结果表明:在荷载较大时,随着锚筋直径增大,锚杆结构承载比例有明显上升,但若锚筋直径过大,锚杆的承载比例随锚筋直径增加而提升空间较小;锚杆角度减小,斜锚短桩基础在纯上拔荷载作用下的抗拔承载能力提高,但其对水平荷载的抵抗能力会减弱;综合考虑,在粉砂岩地层中,锚筋直径40 mm,锚杆角度25°为斜锚短桩基础最优设计参数。

关键词：斜锚短桩基础 FLAC3D 抗拔承载特性承载比例

Distribution of Nanhua-Sinian rifts and proto-type basin evolution in southwestern Tarim Basin, NW China

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Petroleum Exploration and Development 2020年第6期47卷 1206-1217页

作者： tian lei ZHANG Huquan LIU Jun ZHANG Nianchun SHI Xiaoqian Research Institute of Petroleum Exploration&Development-Northwest PetroChinaLanzhou 730020China Reservoir Description Key Laboratory of China National Petroleum Corporation Lanzhou 730020China

Based on seismic data,outcrop evidence,logging data and regional aeromagnetic data,the distribution of Nanhua–Sinian rifts in the southwestern Tarim Basin was analyzed,and on the basis of restoration of lithofacies paleogeography in different periods of Neoproterozoic–Cambrian,the evolution model of the proto-type rift basin was *** Neoproterozoic Rodinia supercontinent split event formed the trigeminal rift system at the edge and inside of the craton in the southwestern Tarim Basin located in the Kunlun piedmont and Maigaiti *** rift in Kunlun piedmont zone was distributed along the E-W direction and was the oceanic rift in the trigeminal rift *** decadent rifts in N-E strike developed in the Luonan and Yubei areas of Maigaiti slope,and the interior of the rifts were characterized by a composite graben-horst structure composed of multiple grabens and *** Neoproterozoic–Cambrian proto-type basin evolution in the southwestern Tarim Basin can be divided into three stages:rift in the Nanhua,embryonic passive continental margin in the Sinian,and stable passive continental margin in the *** the regional tectonic movements in the end of Nanhua and Sinian,the tectonic framework of the southwestern Tarim Basin had not changed significantly,the sedimentary center of Nanhua rift basin showed the characteristics of succession in the Sinian–Early *** Nanhua rift in Kunlun piedmont evolved into a craton marginal depression during the Sinian–Early Paleozoic,while the Luonan decadent rift in the midsection of Maigaiti slope evolved into a sag inside platform in Early Cambrian,constituting the paleogeographic framework of"two paleouplifts and one sag"with the paleouplifts in east and west sides of the *** later evolution of the Luonan decadent rift in the midsection of the Maigaiti slope formed two sets of reservoir-forming assemblages,the Sinian and the Lower Cambrian ones,which are important exploration targets in future.

关键词： rift Nanhua-Sinian Early Cambrian proto-type basin southwestern Tarim Basin

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铁路货车人力制动机紧固器及其标准的优化研究

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铁道技术监督 2024年第6期52卷 12-15页

作者：田雷张小强晁阳中国铁道科学研究院集团有限公司运输及经济研究所北京100081 中国国家铁路集团有限公司运输部北京100844

针对TB/T 3095—2004《铁道货车防溜紧固器统一技术条件》部分条款出现不适应现场实际的问题,通过调研相关运输企业紧固器的配备、使用情况,提出设计优化需求。基于TB/T 3095—2004中条款内容溯源和技术要求,结合紧固器优化需求,从紧固... 详细信息

针对TB/T 3095—2004《铁道货车防溜紧固器统一技术条件》部分条款出现不适应现场实际的问题,通过调研相关运输企业紧固器的配备、使用情况,提出设计优化需求。基于TB/T 3095—2004中条款内容溯源和技术要求,结合紧固器优化需求,从紧固器的报废规定、性能要求、试验方法和发展需求等方面,对标准内容提出修改建议,为标准化研究工作提供参考。

关键词：铁道货车人力制动机紧固器结构设计检验检测行业标准

Characteristics of trace elements of the No.9 coal seam from the Anjialing Mine, Ningwu coalfield, China

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Chinese Journal Of Geochemistry 2015年第3期34卷 391-400页

作者： Wang Jinxi Wang Qi tian lei Key Laboratory of Resource Exploration Research of Hebei Province Hebei University of Engineering

Trace elements of the No. 9 coal seam from Aanjialing mine were measured by ICP–MS. The results indicated that Li, Ga, Cr, Sr, Zr and Pb are significantly enriched in the No. 9 coal seam. The Li and Ga contents in most of the coal seam samples reached an economically valuable level. Most trace elements were enriched near the roof and floor. The data from the Sr/Ba, V/Zn, Th/U, V/Zr and V/Ni ratios reveal that during this period, the peat swamp from this area was formed in swamp water, which was influenced by sea-water or, in an sea-land transition environment, where the ancient water salinity was slightly high. The Eu negative anomaly obviously shows that the rare earth elements are consistent with the terrigenous rocks, so we deduced that the rare earth elements contained in the mineral may mainly come from terrestrial detritus.

关键词：微量元素特征宁武煤田煤层煤矿微量元素富集陆源碎屑岩中国 ICP-MS

Elevation spatial characteristic investigation based on 3D massive MIMO channel measurements at 6 GHz

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The Journal of China Universities of Posts and Telecommunications 2018年第3期25卷 1-7,91页

作者： Zheng Zhe tian lei Zhang Jianhua State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications

As the key technology of the 5th generation （5G）, 3-dimensional （3D） massive multi-input and multi-output （MIMO） is expected to be widely used in small cell network （SCN）. In this paper, in order to investigated the tradeoff between limited size in SCN and the capacity gain from increasing antenna elements, the spatial performances of 3D massive MIMO based on a 512×16 MIMO channel measurements at 6 GHz in urban microcell （UMi） scenario are studied. Enormous channel impulse responses （CIR） are collected and reconstructed, which enables us to present comparative results of the capacity and the eigenvalue spread （ES）. Furthermore, the impacts of antenna element number and spacing on system performance are investigated, i. e. , 32, 64, 128 elements are selected from the 512 transmitter （Tx） array with elevation interval spacing being 0.5, 1 and 2 wavelengths for each. Interestingly, the capacity gap can be obviously observed on the comparison between the 1 and 2 wavelength antenna spacing cases, which implies that correlation cannot be ignored when the antenna spacing is larger than 1 wavelength when massive antennas are equipped. The contrast results show that the capacities are enlarged with the increasing of antenna elements number, and larger antenna spacing will lead to higher channel capacity as expected. However, the capacity gains brought by the increasing of antenna spacing will descend to certain degrees as the antenna number increases. Collectively, these results will provide further insights into 3D massive MIMO utilization.

关键词： massive MIMO channel capacity eigenvalue spread elements spacing antenna number

A review of trachoma history in China: research, prevention, and control

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Science China(Life Sciences) 2016年第6期59卷 541-547页

作者： Ningli Wang Shijing Deng lei tian Beijing Institute of Ophthalmology Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical UniversityBeijing Ophthalmology & Visual Sciences Key Laboratory

Trachoma is one of the most widespread blinding eye diseases, which is harmful to human visual health. The efforts to prevent and control trachoma in China can be divided into three periods, i.e., highly epidemic period, research on pathogenesis and control of trachoma, and blinding trachoma elimination and epidemiological evaluation. In 1956, Prof. Feifan Tang and Xiaolou Zhang first discovered and isolated Chlamydia trachomatis, which clarified the cause of trachoma, and kick-started a fresh chapter in trachoma research, prevention, and control around the world. Although, the prevalence of trachoma differed in different areas, the average prevalence once exceeded 50% and was as high as 90% in some areas before and at early liberation of China. Therefore, the government-led efforts were made to comprehensively prevent and control trachoma, including development of National Plan for the Prevention and Control of Trachoma, nationwide screening and treatment of trachoma, implementation of National Patriotic Health Campaign and improvement of water supply and lavatories. After decades of effort, China reached the goal of eliminating blinding trachoma in 2015. China has gained remarkable achievements in the prevention and treatment of trachoma, making outstanding contributions toward the goal of eliminating trachoma worldwide. The research, prevention, and control of trachoma in China were reviewed in this paper.

关键词： Chlamydia Chlamydia trachomatis blinding trachoma

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浅述国内外慢病风险评估工具研究进展

健康体检与管理 2024年第3期5卷 257-263,272页

作者：贺改丽田磊王鹏北京大学第三医院健康管理中心北京100191

随着我国经济的发展和生活水平的提高,慢性非传染性疾病(简称慢病)的发病率逐步上升,成为重大公共健康问题。本文综述了国内外慢病风险评估工具的研究进展,重点分析了心血管疾病(CVD)、糖尿病和脑卒中的风险评估工具,并探讨了生物标记物... 详细信息

随着我国经济的发展和生活水平的提高,慢性非传染性疾病(简称慢病)的发病率逐步上升,成为重大公共健康问题。本文综述了国内外慢病风险评估工具的研究进展,重点分析了心血管疾病(CVD)、糖尿病和脑卒中的风险评估工具,并探讨了生物标记物在CVD风险评估中的应用,以及人工智能技术在风险评估中的潜力与挑战。研究表明,多种风险评估工具能有效预测个体的慢病发病风险,但同时也存在数据依赖性、透明度和可解释性问题、技术局限性与误判风险等挑战。未来研究应注重工具的个性化和精准化,加强跨学科合作和技术创新,提高公众对慢病风险评估工具的认知和使用率。

关键词：慢性非传染性疾病心血管疾病糖尿病脑卒中风险评估工具