An Efficient Encrypted Speech Retrieval Based on Unsupervised Hashing and B+ Tree Dynamic Index

Existing speech retrieval systems are frequently confronted with expanding volumes of speech data.The dynamic updating strategy applied to construct the index can timely process to add or remove unnecessary speech data to meet users’real-time retrieval requirements.This study proposes an efficient method for retrieving encryption speech,using unsupervised deep hashing and B+ tree dynamic index,which avoid privacy leak-age of speech data and enhance the accuracy and efficiency of retrieval.The cloud’s encryption speech library is constructed by using the multi-threaded Dijk-Gentry-Halevi-Vaikuntanathan(DGHV)Fully Homomorphic Encryption(FHE)technique,which encrypts the original speech.In addition,this research employs Residual Neural Network18-Gated Recurrent Unit(ResNet18-GRU),which is used to learn the compact binary hash codes,store binary hash codes in the designed B+tree index table,and create a mapping relation of one to one between the binary hash codes and the corresponding encrypted speech.External B+tree index technology is applied to achieve dynamic index updating of the B+tree index table,thereby satisfying users’needs for real-time retrieval.The experimental results on THCHS-30 and TIMIT showed that the retrieval accuracy of the proposed method is more than 95.84%compared to the existing unsupervised hashing methods.The retrieval efficiency is greatly improved.Compared to the method of using hash index tables,and the speech data’s security is effectively guaranteed.

The Dynamic Plateau Monsoon Index and Its Association with General Circulation Anomalies

Based on monthly ECMWF reanalysis-Interim （ERA-Interim） reanalysis data, along with monthly precipitation and temperature data, the Dynamic Plateau Monsoon Index （DPMI） is defined. The results of a contrast analysis of the DPMI versus the Traditional Plateau Monsoon Index （TPMI） are described. The response of general circulation to northern Qinghai-Xizang Plateau summer monsoon anomalies and the correlation of the DPMI with general circulation anomalies are investigated. The results show that, the DPMI reflected meteorological elements better and depicted climate variation more accurately than the TPMI. In years when the plateau summer monsoon is strong, the low over the plateau and the trough near the eastern coast of Asia are deeper and higher than normal over South China. This correlation corresponds to two anomalous cyclones over the plateau and the eastern coast of Asia and an anomalous anticyclone in South China. The plateau and its adjacent regions are affected by anomalous southwesterly winds that transport more moisture to South China and cause more precipitation. The lower reaches of the Yangtze River appear to receive more precipitation by means of the strong westerly water vapor flow transported from the ＂large triangle affecting the region＂. In years when the plateau summer monsoon is weak, these are opposite. The plateau monsoon is closely related to the intensity and position of the South Asian high, and the existence of a teleconnection pattern in the mid-upper levels suggests a possible linkage of the East Asian monsoon and the Indian monsoon to the plateau summer monsoon.

DYNAMIC RESPONSE OF ROLLER GEAR INDEXING CAM SYSTEM CONSIDERING CLEARANCE AND MOTOR CHARACTERISTIC

The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexibility are developed and solved.The results show that clearance affects primarily the response on turret,and has little effects on the responses on rotary table.At the same time,the velocity fluctuation of motor shaft is not serious for the existence of inertia of reducer,and the high frequency of velocity fluctuation of camshaft is related with the torsion stiffness of shaft and the clearance between pairs.

Trajectory engineering via a space-fractional Schrodinger equation with dynamic linear index potential

We theoretically and numerically study the propagation dynamics of a Gaussian beam modeled by the fractional Schrodinger equation with different dynamic linear potentials. For the limited case α = 1(α is the Lévy index) in the momentum space, the beam suffers a frequency shift which depends on the applied longitudinal modulation and the involved chirp. While in the real space, by precisely controlling the linear chirp, the beam will exhibit two different evolution characteristics: one is the zigzag trajectory propagation induced by multi-reflection occurring at the zeros of spatial spectrum,the other is diffraction-free propagation. Numerical simulations are in full accordance with the theoretical results. Increase of the Lévy index not only results in the drift of those turning points along the transverse direction, but also leads to the delocalization of the Gaussian beam.

水稻强化栽培试验研究

选用穗数型常规水稻粤香占和大穗型杂交水稻粤杂122进行强化栽培(SRI)试验.结果表明:随着插植规格增大,粤香占和粤杂122都表现出生育期延迟,个体分蘖数、成穗率、每穗总粒数和千粒质量也相应增加的特点.2个品种各生育期群体茎蘖动态、叶面积指数、干物质积累、有效穗都随着插植规格增大而减少,但品种间存在明显差异.

COLIN:A Cache-Conscious Dynamic Learned Index with High Read/Write Performance

The recently proposed learned index has higher query performance and space efficiency than the conventional B+-tree.However,the original learned index has the problems of insertion failure and unbounded query complexity,meaning that it supports neither insertions nor bounded query complexity.Some variants of the learned index use an out-of-place strategy and a bottom-up build strategy to accelerate insertions and support bounded query complexity,but introduce additional query costs and frequent node splitting operations.Moreover,none of the existing learned indices are cache-friendly.In this paper,aiming to not only support efficient queries and insertions but also offer bounded query complexity,we propose a new learned index called COLIN(Cache-cOnscious Learned INdex).Unlike previous solutions using an out-of-place strategy,COLIN adopts an in-place approach to support insertions and reserves some empty slots in a node to optimize the node’s data placement.In particular,through model-based data placement and cache-conscious data layout,COLIN decouples the local-search boundary from the maximum error of the model.The experimental results on five workloads and three datasets show that COLIN achieves the best read/write performance among all compared indices and outperforms the second best index by 18.4%,6.2%,and 32.9%on the three datasets,respectively.

Land use/land cover change responses to ecological water conveyance in the lower reaches of Tarim River,China

The Tarim River is the longest inland river in China and is considered as an important river to protect the oasis economy and environment of the Tarim Basin.However,excessive exploitation and over-utilization of natural resources,particularly water resources,have triggered a series of ecological and environmental problems,such as the reduction in the volume of water in the main river,deterioration of water quality,drying up of downstream rivers,degradation of vegetation,and land desertification.In this study,the land use/land cover change(LUCC)responses to ecological water conveyance in the lower reaches of the Tarim River were investigated using ENVI(Environment for Visualizing Images)and GIS(Geographic Information System)data analysis software for the period of 1990-2018.Multi-temporal remote sensing images and ecological water conveyance data from 1990 to 2018 were used.The results indicate that LUCC covered an area of 2644.34 km^(2) during this period,accounting for 15.79%of the total study area.From 1990 to 2018,wetland,farmland,forestland,and artificial surfaces increased by 533.42 km^(2)(216.77%),446.68 km^(2)(123.66%),284.55 km^(2)(5.67%),and 57.51 km^(2)(217.96%),respectively,whereas areas covered by grassland and other land use/land cover types,such as Gobi,bare soil,and deserts,decreased by 103.34 km2(14.31%)and 1218.83 km2(11.75%),respectively.Vegetation area decreased first and then increased,with the order of 2010<2000<1990<2018.LUCC in the overflow and stagnant areas in the lower reaches of the Tarim River was mainly characterized by fragmentation,irregularity,and complexity.By analyzing the LUCC responses to 19 rounds of ecological water conveyance in the lower reaches of the Tarim River from 2000 to the end of 2018,we proposed guidelines for the rational development and utilization of water and soil resources and formulation of strategies for the sustainable development of the lower reaches of the Tarim River.This study provides scientific guidance for optimal scheduling of water resources in the region.

Predictability of the East Asian Winter Monsoon Indices by the Coupled Models of ENSEMBLES

The seasonal predictability of various East Asian winter monsoon （EAWM） indices was investigated in this study based on the retrospective forecasts of the five state-of-the-art coupled models from ENSEMBLES for a 46-year period of 19612006.It was found that the ENSEMBLES models predict five out of the 21 EAWM indices well,with temporal correlation coefficients ranging from 0.54 to 0.61.These five indices are defined by the averaged lower-tropospheric winds over the low latitudes （south of 30°N）.Further analyses indicated that the predictability of these five indices originates from their intimate relationship with ENSO.A cross-validated prediction,which took the preceding （November） observed Nifo3.4 index as a predictor,gives a prediction skill almost identical to that shown by the model.On the other hand,the models present rather low predictability for the other indices and for surface air temperature in East Asia.In addition,the models fail to reproduce the relationship between the indices of different categories,implying that they cannot capture the tropicalextratropical interaction related to EAWM variability.Together,these results suggest that reliable prediction of the EAWM indices and East Asian air temperature remains a challenge.

A survey of time consistency of dynamic risk measures and dynamic performance measures in discrete time: LM-measure perspective

In this work we give a comprehensive overview of the time consistency property of dynamic risk and performance measures,focusing on a the discrete time setup.The two key operational concepts used throughout are the notion of the LMmeasure and the notion of the update rule that,we believe,are the key tools for studying time consistency in a unified framework.

Fuzzy Genetic Sharing for Dynamic Optimization

Recently,genetic algorithms(GAs) have been applied to multi-modal dynamic optimization(MDO).In this kind of optimization,an algorithm is required not only to find the multiple optimal solutions but also to locate a dynamically changing optimum.Our fuzzy genetic sharing(FGS) approach is based on a novel genetic algorithm with dynamic niche sharing(GADNS).FGS finds the optimal solutions,while maintaining the diversity of the population.For this,FGS uses several strategies.First,an unsupervised fuzzy clustering method is used to track multiple optima and perform GADNS.Second,a modified tournament selection is used to control selection pressure.Third,a novel mutation with an adaptive mutation rate is used to locate unexplored search areas.The effectiveness of FGS in dynamic environments is demonstrated using the generalized dynamic benchmark generator(GDBG).

某高速公路服务区冬季热舒适研究

针对高速公路服务区的热湿环境特征,以某高速公路上的服务区为研究对象,采用问卷调查和现场测试相结合的方法,对服务区内的热湿环境进行研究,讨论了不同环境参数对人体热舒适的影响,同时采用动态热舒适评价指标:相对热指标(Relative Warmth Index,RWI)和热损失率(Heat Deficit Rate,HDR),对冬季服务区公共区域过渡状态下的热舒适环境进行分析,得出过渡状态下的人体热舒适变化情况。调查结果显示,参与调查的人员整体表示对室内热湿环境接受,同时测量结果表明,服务区超市内空气平均温度为17.4℃,平均相对湿度为32.8%,室内平均空气流速为0.16 m/s,均处于人体可接受范围内。研究表明,采用动态评价指标与问卷调查相结合的方法能够准确评价冬季高速公路服务区热环境;寒冷季节,服务区室内空调温度不宜设置过高,避免因环境突变造成人体不舒适。

Changes in Aridity in Response to the Global Warming Hiatus

The global warming slowdown or warming hiatus, began around the year 2000 and has persisted for nearly 15 years. Most studies have focused on the interpretation of the hiatus in temperature. In this study, changes in a global aridity index （AI） were analyzed by using a newly developed dynamical adjustment method that can successfully identify and separate dynamically induced and radiatively forced aridity changes in the raw data. The AI and Palmer Drought Severity Index produced a wetting zone over the mid-to-high latitudes of the Northern Hemisphere in recent decades. The dynamical adjustment analysis suggested that this wetting zone occurred in response to the global warming hiatus. The dynamically induced AI （DAI） played a major role in the AI changes during the hiatus period, and its relationships with the North Atlantic Oscillation （NAO）, Pacific Decadal Oscillation （PDO）, and Atlantic Multi-decadal Oscillation （AMO） also indicated that different phases of the NAO, PDO, and AMO contributed to dif- ferent performances of the DAI over the Northern Hemisphere. Although the aridity wetting over the mid-to-high lat- itudes may relieve long-term drying in certain regions, the hiatus is temporary, and so is the relief. Accelerated glob- al warming will return when the NAO, PDO, and AMO revert to their opposite phases in the future, and the wetting zone is likely to disappear.