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| 1 | Some new pre-warning criteria for creep slope failure显示文摘The forecasting of the failure time of a slope remains a worldwide problem because of many different possibilities of geological conditions in combination with many varying external factors such as climate and vegetation,and not well-defined or unknown time effects in deformation and failure models.The aim of this paper is to suggest a new method to carry out the phase division and to explore tangential angular features of the displacement-time curve of creep slopes as well as the acceleration characteristics in the process of slope deformation and the pre-warning criteria for critical failure.An imminent failure is pro-ceeded with usually three basic deformation phases,namely primary creep('decelerated') ,secondary creep('steadystate') and tertiary creep('accelerated') .Mostly,only during the accelerated phase the imminence of a possible slope failure is rec-ognized.The analysis of displacement data from a series of landslides allowed to recognize different evolutionary patterns of displacement.A quantitative approach was proposed to describe the tangential angle of the displacement-time curve and a new criterion based on the angle was put forward to divide the accelerated phase into three sub-phases:initial acceleration,medium acceleration,and the critical failure.A pre-warning criterion for critical failure is also proposed consequently. Changes of acceleration showed completely different characteristics from those of cumulative displacement and displacement in the process of slope deformation.The values of acceleration usually oscillate around 0 prior to the critical failure phase,whereas the acceleration increases abruptly when the deformation moves into the critical failure phase.This allows,therefore,for a method to forecast the time of the failure.So it is possible to define different alert acceleration threshold values to be used for emergency management. | HACK Robert | 2011 | Science China(Technological Sciences)2011，54，S1： | 15 |
| 2 | A novel image segmentation approach for wood plate surface defect classification through convex optimization显示文摘Detection of wood plate surface defects using image processing is a complicated problem in the forest industry as the image of the wood surface contains different kinds of defects. In order to obtain complete defect images, we used convex optimization(CO) with different weights as a pretreatment method for smoothing and the Otsu segmentation method to obtain the target defect area images. Structural similarity(SSIM) results between original image and defect image were calculated to evaluate the performance of segmentation with different convex optimization weights. The geometric and intensity features of defects were extracted before constructing a classification and regression tree(CART) classifier. The average accuracy of the classifier is 94.1% with four types of defects on Xylosma congestum wood plate surface: pinhole, crack,live knot and dead knot. Experimental results showed that CO can save the edge of target defects maximally, SSIM can select the appropriate weight for CO, and the CART classifier appears to have the advantages of good adaptability and high classification accuracy. | Zhanyuan Chang Jun Cao Yizhuo Zhang | 2018 | Journal of Forestry Research2018，29，6： | 14 |
| 3 | Review of coal and gas outburst in Australian underground coal mines显示文摘Outburst of coal and gas represents a significant risk to the health and safety of mine personnel working in development and longwall production face areas.There have been over 878 outburst events recorded in twenty-two Australian underground coal mines.Most outburst incidents have been associated with abnormal geological conditions.Details of Australian outburst incidents and mining experience in conditions where gas content was above current threshold levels are presented and discussed.Mining experience suggests that for gas con-tent below 9.0 m^3/t,mining in carbon dioxide(CO2)rich seam gas conditions does not pose a greater risk of outburst than mining in CH4 rich seam gas conditions.Mining experience also suggests that where no abnormal geological structures are present that mining in areas with gas content greater than the current accepted threshold levels can be undertaken with no discernible increase in outburst risk.The current approach to determining gas content threshold limits in Australian mines has been effective in prevent-ing injury from outburst,however operational experience suggests the current method is overly conser-vative and in some cases the threshold limits are low to the point that they provide no significant reduction in outburst risk.Other factors that affect outburst risk,such as gas pressure,coal toughness and stress and geological structures are presently not incorporated into outburst threshold limits adopted in Australian mines.These factors and the development of an outburst risk index applicable to Australian underground coal mining conditions are the subject of ongoing research. | Dennis J.Black | 2019 | International Journal of Mining Science and Technology2019，29，6： | 14 |
| 4 | An improved binarization algorithm of wood image defect segmentation based on non-uniform background显示文摘In this study,an image binarization optimization algorithm,based on local threshold algorithms,is proposed because global and traditional local threshold segmentation algorithms cannot effectively address the problems of nonuniform backgrounds of wood defect images.The proposed algorithm calculates the threshold by the mean,standard deviation and the extreme value of the window.The results indicate that this modified algorithm enhances the image segmentation for wood defect images on a complex background,which is much superior to the global threshold algorithm and the Bernsen algorithm,and slightly better than the Niblack algorithm and Sauvola algorithm.Compared with similar models,the algorithm proposed in this paper has higher segmentation accuracy,as high as 92.6%for wood defect images with a complex background. | Wei Luo Liping Sun | 2019 | Journal of Forestry Research2019，30，4： | 13 |
| 5 | Early warning system for shallow landslides using rainfall threshold and slope stability analysis显示文摘A combined cluster and regression analysis were performed for the first time to identify rainfall threshold that triggers landslide events in Amboori, Kerala, India. Amboori is a tropical area that is highly vulnerable to landslides. The 2, 3, and 5-day antecedent rainfall data versus daily rainfall was clustered to identify a cluster of critical events that could potentially trigger landslides. Further, the cluster of critical events was utilized for regression analysis to develop the threshold equations. The 5-day antecedent(xvariable) vs. daily rainfall(y-variable) provided the best fit to the data with a threshold equation of y = 80.7-0.1981 x. The intercept of the equation indicates that if the 5-day antecedent rainfall is zero, the minimum daily rainfall needed to trigger the landslide in the Amboori region would be 80.7 mm. The negative coefficient of the antecedent rainfall indicates that when the cumulative antecedent rainfall increases, the amount of daily rainfall required to trigger monsoon landslide decreases. The coefficient value indicates that the contribution of the 5-day antecedent rainfall is~20% to the landslide trigger threshold. The slope stability analysis carried out for the area, using Probabilistic Infinite Slope Analysis Model(PISA-m), was utilized to identify the areas vulnerable to landslide in the region. The locations in the area where past landslides have occurred demonstrate lower Factors of Safety(FS) in the slope stability analysis. Thus, rainfall threshold analysis together with the FS values from slope stability can be suitable for developing a simple, cost-effective, and comprehensive early-warning system for shallow landslides in Amboori and similar regions. | Shruti Naidu K.S.Sajinkumar Thomas Oommen V.J.Anuja Rinu A.Samuel C.Muraleedharan | 2018 | Geoscience Frontiers2018，9，6： | 12 |
| 6 | Threshold quantum secure direct communication without entanglement显示文摘For the first time, a threshold quantum secure direct communication (TQSDC) scheme is presented. Similar to the classical Shamir's secret sharing scheme, the sender makes n shares, S1, …, Sn of secret key K and each receiver keeps a share secretly. If the sender wants to send a secret message M to the receivers, he en-codes the information of K and M on a single photon sequence and sends it to one of the receivers. According to the secret shares, the t receivers sequentially per-form the corresponding unitary operations on the single photon sequence and ob-tain the secret message M. The shared shares may be reusable if it can be judged that there is no eavesdropper in line. We discuss that our protocol is feasible with current technology. | YANG YuGuang1,3 & WEN QiaoYan2 1 College of Computer Science and Technology, Beijing University of Technology, Beijing 100022, China 2 School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China 3 State Key Laboratory of Information Security (Graduate School of Chinese Academy of Sciences), Beijing 100049, China | 2008 | Science China(Physics,Mechanics & Astronomy)2008，51，2： | 11 |
| 7 | Development of a model to simulate soil heavy metals lateral migration quantity based on SWAT in Huanjiang watershed,China显示文摘Lateral transportation of soil heavy metals in rainfall events could significantly increase the scope of pollution. Therefore, it is necessary to develop a model with high accuracy to simulate the migration quantity of heavy metals. A model for heavy metal migration simulation was developed based on the SWAT(Soil and Water Assessment Tool) model. This model took into consideration the influence of soil p H value, soil particle size, runoff volume, sediment amount,concentration of water-soluble heavy metals dissolved in runoff and insoluble absorbed to the soil particles. This model was reasonable in Huanjiang watershed, Guangxi Zhuang Autonomous Region, south China, covering an area of 273 km^2. The optimal drainage area threshold was determined by analyzing the effects of watershed subdivision on the simulation results to ensure the simulation accuracy. The main conclusions of this paper were:(1) watershed subdivision could affect simulation migration quantity of heavy metals;(2) the quantity of heavy metals transported by sediment accounted for 97%–99% of the total migration quantity in the study watershed. Therefore, sediment played the most important role in heavy metal migration;(3) the optimal drainage area threshold percentage to ensure high simulation accuracy was determined to be 2.01% of the total watershed;(4) with the optimal threshold percentage, this model could simulate the migration quantity of As, Pb and Cd accurately at the total watershed and subwatershed level. The results of this paper were useful for identifying the key regions with heavy metal migration. | Pengwei Qiao Mei Lei Sucai Yang Jun Yang Xiaoyong Zhou Nan Dong Guanghui Guo | 2019 | Journal of Environmental Sciences2019，31，3： | 11 |
| 8 | 基于Cacti的Threshold插件短信报警流量监测研究显示文摘鉴于流量监测在网络管理中的重要性,本文提出并设计一个在RedHatAs5下基于Cacti的短信报警监测系统。该系统采用B/S结构,以Cacti作为监控管理端,并在管理端上安装Threshold插件和飞信机器人软件,实现对整个网中多个网络设备进行不间断的流量集中式监控。通过在Cacti上,对监测设备设置运行状态报警阈值,实现对网络设备运行过程中的异常流量状态进行短信报警。实验结果和实际应用验证了该系统的有效性。 | 马彦图 康立军 | 2011 | 计算机与现代化2011，，12： | 10 |
| 9 | Birth defects in pregestational diabetes:Defect range,glycemic threshold and pathogenesis显示文摘Currently,60 million women of reproductive age(18-44 years old) worldwide,and approximately 3 million American women have diabetes mellitus,and it has been estimated that this number will double by 2030.Pregestational diabetes mellitus(PGD) is a significant public health problem that increases the risk for structural birth defects affecting both maternal and neonatal pregnancy outcome.The most common types of human structural birth defects associated with PGD are congenital heart defects and central nervous system defects.However,diabetes can induce birth defects in any other fetal organ.In general,the rate of birth defects increases linearly with the degree of maternal hyperglycemia,which is the major factor that mediates teratogenicity of PGD.Stringent prenatal care and glycemic control are effective means to reduce birth defects in PGD pregnancies,but cannot reduce the incidence of birth defects to the rate of that is seen in the nondiabetic population.Studies in animal models have revealed that PGD induces oxidative stress,which activates cellular stress signalling leading to dysregulation of gene expression and excess apoptosis in the target organs,including the neural tube and embryonic heart.Activation of the apoptosis signalregulating kinase 1(ASK1)-forkhead transcription factor 3a(Fox O3a)-caspase 8 pathway causes apoptosis in the developing neural tube leading to neural tube defects(NTDs).ASK1 activates the c-Jun-N-Terminal kinase 1/2(JNK1/2),which leads to activation of the unfolded protein response and endoplasmic reticulum(ER) stress.Deletion of the ASK1 gene,the JNK1 gene,or the JNK2 gene,or inhibition of ER stress by 4-Phenylbutyric acid abrogates diabetes-induced apoptosis and reduces the formation of NTDs.Antioxidants,such as thioredoxin,which inhibits the ASK1-Fox O3a-caspase 8 pathway or ER stress inhibitors,may prevent PGD-induced birth defects. | Rinat Gabbay-Benziv E Albert Reece Fang Wang Peixin Yang | 2015 | World Journal of Diabetes2015，6，3： | 10 |
| 10 | A new dynamic pushback control method for reducing fuel-burn costs: Using predicted taxi-out time显示文摘Long departure-taxi-out time leads to significant airport surface congestion, fuel-burn costs, and excessive emissions of greenhouse gases. To reduce these undesirable effects, a Predicted taxi-out time-based Dynamic Pushback Control(PDPC) method is proposed. The implementation of this method requires two steps: first, the taxi-out times for aircraft are predicted by the leastsquares support-vector regression approach of which the parameters are optimized by an introduced improved Firefly algorithm. Then, a dynamic pushback control model equipped with a linear gate-hold penalty function is built, along with a proposed iterative taxiway queue-threshold optimization algorithm for solving the model. A case study with data obtained from Beijing International airport(PEK) is presented. The taxi-out time prediction model achieves predictive accuracy within 3 min and 5 min by 84.71% and 95.66%, respectively. The results of the proposed pushback method show that total operation cost and fuel-burn cost achieve a 14.0% and 21.1%reduction, respectively, as compared to the traditional K-control policy.(3) From the perspective of implementation, using PDPC policy can significantly reduce the queue length in taxiway and taxi-out time. The total operation cost and fuel-burn cost can be curtailed by 37.2% and 52.1%,respectively, as compared to the non-enforcement of any pushback control mechanism. These results show that the proposed pushback control model can reduce fuel-burn costs and airport surface congestion effectively. | Guan LIAN Yaping ZHANG Zhiwei XING Qian LUO Shaowu CHENG | 2019 | Chinese Journal of Aeronautics2019，32，3： | 10 |
| 11 | Effect of suspended sediment grain size on channel sedimentation in the lower Yellow River and some implications显示文摘Based on the data of suspended sediment transport and channel sedimentation in various grain size fractions in the period of 1962―1985, the relationship between channel sedimentation in the lower Yellow River and sediment input has been plotted with respect to each grain size fraction. Several fill-scour thresholds in sediment input have been identified from these graphs. It was found that the fill-scour threshold in sediment input decreases with the increase in fraction grain size. The correlation coefficient between channel sedimentation and sediment input becomes larger with the increasing fraction grain size, indicating that channel sedimentation depends more on coarser grain size fractions than on smaller ones. The fraction channel sedimentation induced by unit change of fraction sediment input increases with grain size. Of the input of sediment larger than 0.025 mm, 43.73% was deposited on the channel, and for inputs of sediments larger than 0.05 mm and larger than 0.10 mm, 76.61% and 97.68% were deposited on the channel, respectively. Thus, for reduction of each ton of sediment larger than 0.10 mm from the drainage basin, the resultant reduction in channel sedimentation in the lower Yellow River would be 1.275 times that for the sediment larger than 0.10 mm, and 2.234 times that for the sediment larger than 0.025 mm. Therefore, if the erosion and sediment control measures are enforced in the areas where >0.05 or >0.10 mm sediment is produced, then the best beneficial will be achieved in reducing sedimentation in the lower Yellow River. | XU JiongXin HU ChunHong CHEN JianGuo | 2009 | Science China(Technological Sciences)2009，52，8： | 9 |
| 12 | 不同刺激频率与时间经穴经皮神经电刺激对电流感觉阈值的影响显示文摘目的分析不同频率与时间的经穴经皮神经电刺激对电流感觉阈值(CPT)的影响。方法通过测量颏孔区和手臂区的电流感觉阈值评价经穴经皮神经电刺激的效用。对30例健康志愿受试者的合谷穴分次给予不同刺激时间和刺激频率的经皮神经电刺激,并测量同侧颏孔区和手臂区的电流感觉阈值。结果颏孔区电流感觉阈值升高。低频电刺激对慢痛(5 Hz CPT)有明显抑制作用(P<0.05),高频电刺激对快痛(250 Hz CPT)和慢痛均有抑制作用(P<0.05)。经皮神经电刺激的刺激频率(β=0.363)比刺激时间(β=0.274)对疼痛的抑制作用的影响更明显。结论经穴经皮神经电刺激确实可以影响特定反应区的感觉阈值,且治疗频率的选择比单纯延长治疗时间更为重要。 | 李娜 吴双 吕国义 | 2014 | 天津医药2014，42，6： | 9 |
| 13 | Research of optical rainfall sensor based on CCD linear array显示文摘Rainfall monitoring is one of the most important meteorological observation elements for the disaster weather. The maintenance of current tipping bucket rain gauge and weighing type rain gauge is a critical issue. The optical rainfall sensor based on CCD linear array is mainly studied in this paper. Because of the maintenance-free time and good adaptability,it can be widely used in the automatic rainfall monitoring in severe environment and have a good perspective in using. | YANG Bifeng LIU Yuyan LU Ying WU Shangqian | 2015 | Instrumentation2015，2，3： | 9 |
| 14 | An SIS Epidemic Model with Stage Structure and a Delay显示文摘A disease transmission model of SIS type with stage structure and a delay is formulated. Stability of the disease free equilibrium, and existence, uniqueness, and stability of an endemic equilibrium, are investigated for the model. The stability results arc stated in terms of a key threshold parameter. The effects of stage structure and time delay on dynamical behavior of the infectious disease are analyzed. It is shown that stage structure has no effect on the epidemic model and Hopf bifurcation can occur as the time delay increases. | Yan-ni Xiao, Lan-sun ChenAcademy of Mathematics and System Sciences, Chinese Academy of Sciences. Beijing 100080. China | 2002 | Acta Mathematicae Applicatae Sinica2002，18，4： | 9 |
| 15 | Study on patterns and chemical features of NO effect on marine phytoplankton growth显示文摘This article discusses the patterns of NO effect on marine phytoplankton growth from chemical perspective.The experimental results of four algae,which are Platymonas hal-golandica var.tsingtaoensis,Platymonas subcordiformis,Skeletonema costatum and Nitzschia closterium farma minutissima,are as follows:(i) In f/2 medium or f/50 medium,the growth of these four algae was obviously promoted or inhibited when nitric oxide of different concentrations was added once or twice each day during the cultivation;(ii) The NO effects on the growth of marine phytoplankton are in normal distribution.Different phytoplankton has different optimum NO concentration,which is consistent with the influence of NO on the growth of high plants;(iii) The effect of NO on Platymonas halgolandica var.tsingtaoensi,which is a food alga,is different from that on the red tide algae Skeletonema costatum and Nitzschia closterium farma minutis-sima.The authors put forward a new opinion that every alga has its own NO threshold concen-tration.All the above results may provide new clues to understand the formation of red tide. | ZHANG Zhengbin LIN Cai LIU Chunying XING Lei WU Zhenzhen SUN Feng | 2005 | Science China Chemistry2005，48，4： | 9 |
| 16 | Threshold quantum secret sharing between multi-party and multi-party显示文摘A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique. | YANG YuGuang1,2,3 & WEN QiaoYan4 1 College of Computer Science and Technology,Beijing University of Technology,Beijing 100124,China 2 State Key Laboratory of Integrated Services Network,Xidian University,Xi’an 710071,China 3 State Key Laboratory of Information Security (Graduate University of Chinese Academy of Sciences),Beijing 100049,China 4 State Key Laboratory of Networking and Switching Technology,Beijing University of Posts and Tele-communications,Beijing 100876,China | 2008 | Science China(Physics,Mechanics & Astronomy)2008，51，9： | 8 |
| 17 | 基于CUDA的彩色超声血流成像显示文摘彩色超声血流成像在医学超声诊断中得到了广泛的运用。对前期所提出的超声血流成像图形处理器(GPU)的处理框架做出了两点改进:在壁滤波器模块并行实现Regression滤波器,替换原来的并行有限冲激响应(FIR)滤波器;在后处理模块中,加入了并行实现的Threshold box滤波器,改善了血流的均匀性。实验结果表明:GPU并行实现的运算效率是中央处理器(CPU)串行实现的16.2倍,帧率可以达到70帧/秒。与传统的FIR滤波器相比,Regression滤波器能够得到更高质量的超声血流图像,并且Threshold box滤波器提高了组织/血流鉴定的精确度。 | 范正娟 谭朝炜 刘东权 | 2011 | 计算机应用2011，31，3： | 8 |
| 18 | Derivation of soil Pb/Cd/As thresholds for safety of vegetable planting: A case study for pakchoi in Guangdong Province,China显示文摘Regional guidelines for soil heavy metals,in conjunction with specific crops,are proposed to better assess soil environmental quality.In this study,large amounts of soils with different levels of Pb/Cd/As pollution were collected in Guangdong Province,China,to carry out a pot experiment,which was closer to the actual situation and properties of the heavy metal contaminated soils.Taking the widely planted vegetable pakchoi as the research object,we analyzed the correlations between the Pb/Cd/As concentrations in pakchoi and the total or available soil Pb/Cd/As concentrations and established their optimal regression equations.And then,the total and available soil Pb/Cd/As thresholds for pakchoi were calculated according to the allowable Pb/Cd/As limits in pakchoi and were compared with the current soil assessment standards.Furthermore,a lot of paired vegetable-soil samples in field were collected and their pollution situations were assessed by both the current limit thresholds and the calculated thresholds.Obviously,it was more consistent to assess the Cd and As pollution situation of the vegetable and soil samples with the calculated soil thresholds than the current soil assessment thresholds.It further proved that it was necessary to explore the soil heavy metal thresholds for safety of vegetable in specific regions,which would be more scientific and practical to guide safety production of local agricultural products and effective utilization of soil resources. | LI Fu-rong WEN Dian WANG Fu-hua SUN Fang-fang WANG Xu DU Ying-qiong LIU Xiang-xiang WAN Kai | 2019 | Journal of Integrative Agriculture2019，18，1： | 8 |
| 19 | 一类具有时滞的SIRS传染病模型的研究显示文摘研究了一类具有时滞的SIRS传染病模型,利用对模型的分析,得到了疾病灭绝与否的基本再生数,给出了无病平衡点的全局吸引性及地方病平衡点稳定性的存在条件,证明了疾病的持久性. | 张敬 谢守波 高文杰 | 2011 | 东北师大学报(自然科学版)2011，43，2： | 7 |
| 20 | The transmission link of CAPS navigation and communication system显示文摘The Chinese Area Positioning System (CAPS) is based on communication satellites with integrated capability, which is different from the Global Positioning System (GPS), the International Maritime Satellite Organization (Inmarsat) and so on. CAPS works at C-band, and its navigation information is not directly generated from the satellite, but from the master control station on the ground and transmitted to users via the satellite. The slightly inclined geostationary-satellite orbit (SIGSO) satellites are adopted in CAPS. All of these increase the difficulty in the design of the system and terminals. In this paper, the authors study the CAPS configuration parameters of the navigation master control station, information transmission capability, and the selection of the antenna aperture of the communication center station, as well as the impact of satellite parameters on the whole communication system from the perspective of the transmission link budget. The conclusion of availability of the CAPS navigation system is achieved. The results show that the CAPS inbound communication system forms a new low-data-rate satellite communication system, which can accommodate mass communication terminals with the transmission rate of no more than 1 kbps for every terminal. The communication center station should be configured with a large-aperture antenna (about 10-15 m); spread spectrum com- munication technology should be used with the spreading gain as high as about 40 dB; reduction of the satellite transponder gain attenuation is beneficial to improving the signal-to-noise ratio of the system, with the attenuation value of 0 or 2 dB as the best choice. The fact that the CAPS navigation system has been checked and accepted by the experts and the operation is stable till now clarifies the rationality of the analysis results. The fact that a variety of experiments and applications of the satellite communication system designed according to the findings in this paper have been successfully carried out confirms the correctness of the study results. | CUI JunXia SHI HuLi CHEN JiBin PEI Jun | 2009 | Science China(Physics,Mechanics & Astronomy)2009，52，3： | 6 |
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