A Secure Device Management Scheme with Audio-Based Location Distinction in IoT

Identifying a device and detecting a change in its position is critical for secure devices management in the Internet of Things(IoT).In this paper,a device management system is proposed to track the devices by using audio-based location distinction techniques.In the proposed scheme,traditional cryptographic techniques,such as symmetric encryption algorithm,RSA-based signcryption scheme,and audio-based secure transmission,are utilized to provide authentication,non-repudiation,and confidentiality in the information interaction of the management system.Moreover,an audio-based location distinction method is designed to detect the position change of the devices.Specifically,the audio frequency response(AFR)of several frequency points is utilized as a device signature.The device signature has the features as follows.(1)Hardware Signature:different pairs of speaker and microphone have different signatures;(2)Distance Signature:in the same direction,the signatures are different at different distances;and(3)Direction Signature:at the same distance,the signatures are different in different directions.Based on the features above,amovement detection algorithmfor device identification and location distinction is designed.Moreover,a secure communication protocol is also proposed by using traditional cryptographic techniques to provide integrity,authentication,and non-repudiation in the process of information interaction between devices,Access Points(APs),and Severs.Extensive experiments are conducted to evaluate the performance of the proposed method.The experimental results show that the proposedmethod has a good performance in accuracy and energy consumption.

Distinctions between the Three Major Native Dialects of English

This paper focuses on essential distinctions between the major native dialects of English which are often divided by linguists into the three general categories of the British Isles dialects,those of North America and those of Australasia.English learners might want to learn a standard accent,because maybe they need it in a play or maybe they want to impress their friends,or maybe they want to fit in better in a certain English speaking environment.The paper hopes to help Chinese English learners firstly isolate the distinctions among different but widely-used and officially-accepted accents and then speak good English by means of eliminating incorrect accent by imitating Standard English pronunciation.

On The Distinction between Semantics and Pragmatics

The close relationship between semantics and pragmatics has made it difficult to set a clear boundary between them.Dicussion of the relationship can date back to Morris, whose semiotic trichotomy was taken up by Carnap. Leech, Levinson, Bach and Huang also tried to make a distinction between the two, but no consensus has been reached.

Automatic Identification for Laparoscopic Surgical Procedure for Ligation and Online Distinction of Abnormal Manipulation for Thread Knotting

Laparoscopic surgery is a difficult surgical procedure compared with laparotomy. In particular, considerable skills and care are required for thread knotting in laparoscopic surgery. In this paper, a method for automatic identification of a laparoscopic surgical procedure for ligation and online distinction of an abnormality, defined as any unusual manipulation, in the identified surgical procedure is proposed. Ligation is divided into several individual surgical procedures, and on the basis of the threshold criteria, each surgical procedure is identified. Next, the identified surgical procedure, thread knotting, is classified as either normal or abnormal using a self-organizing map. Finally, to reduce surgical error, an abnormality warning system which warns detection of an unusual manipulation in the surgical procedure to the operator is constructed.

A Research of the Distinctions between English and Chinese Tenses

By observing the grammar systems of Chinese and English,it is found that the uses of tenses between the two languages are very different. It turns out that the Chinese expressions of tenses are more casual and variable,without fixed rules,while for English,more regular. The distinct ways and patterns of expressing tenses between Chinese and English give rise to more frequent errors made by students. Thus,only by a thorough and profound understanding of these distinctions can we find a better way to master the uses of tenses,which requires a reasonable comparison of the tenses between Chinese and English.

A Corpus-Driven Perspective on the Verb Valency Structure of Chinese EFL Learners:A Case Study of“Suggest”and“Advise”

This paper investigates the verb valency structure of English that is used by English as Foreign Language(EFL)learners from a corpus-driven perspective.Specifically,it focuses on the usage of the verbs“suggest”and“advise”in a selected corpus.By analyzing a sample of written and spoken texts,this study attempts to investigate the similarities and differences in the patterns of verb valency between native English speakers and Chinese EFL learners.The findings of this research can contribute to a better understanding of the challenges faced by Chinese EFL learners in acquiring accurate verb valency structures and provide insights for language teachers in designing effective pedagogical approaches.

The Social Group Distinction of Nationalists and Globalists amid COVID-19 Pandemic

The primary discussion in this article is the classification of the typical reactions of social groups in various nations as nationalist and globalist.Subject to the new coronavirus pandemic,nationalists have adopted extreme national security policies,namely,“the nation’s interests prevails;”globalists have adopted moderate policies by complying with the faith of society in the recommendations of the scientific community.The disparate contrasts in values and actions between the two groups are extensively manifested in domestic disease control,attitude toward the World Health Organization,identification of the disease’s source,vaccine research,international cooperation,and social reaction.This research indicates that nationalists largely consist of conservative country leaders,“social elites,”populists,and individuals in the middle-lower class,many of whom uphold racism and extreme nationalism,and that globalists largely consist of international organizations and regional leaders,medical practitioners,intellectuals andphilanthropic entrepreneurs,the middleupper class population.This social group distinction is clarified in accordance with converse ethical value perspectives,ideologies,social group-economic interests,and even national competition positions.Regarding cultural and institutional basics,nationalists uphold neoliberalism,social Darwinism,the law of jungle,and individualism,whereas globalists advocate for social democracy and collectivistic ethnic codes.The two parties have been competing for the high moral ground during and the pandemic,thereby profoundly affecting the relationships of nations worldwide.

A BINOL Based Fluorescence Sensor for Distinction of D-Glucose

A saccharide fluorescent receptor based on 1,1'-binaphthol was developed.The boronic acids groups are di-rectly attached to the 3,3'-positions of BINOL which acted as probes to saccharides.The methyl protected receptor R1 showed better response to D-fructose compared to other saccharides in the fluorescence quenching experiment.To improve the selectivity of D-glucose,the triethylene glycol protected receptor R2 was developed.Receptor R2 has a better water-solubility than R1 that can be applied in completely aqueous environment.With receptor R2,D-glucose has a different response to other saccharides that can be useful for the distinction of D-glucose.

Borehole stability in naturally fractured rocks with drilling mud intrusion and associated fracture strength weakening:A coupled DFN-DEM approach

Borehole instability in naturally fractured rocks poses significant challenges to drilling.Drilling mud invades the surrounding formations through natural fractures under the difference between the wellbore pressure(P w)and pore pressure(P p)during drilling,which may cause wellbore instability.However,the weakening of fracture strength due to mud intrusion is not considered in most existing borehole stability analyses,which may yield significant errors and misleading predictions.In addition,only limited factors were analyzed,and the fracture distribution was oversimplified.In this paper,the impacts of mud intrusion and associated fracture strength weakening on borehole stability in fractured rocks under both isotropic and anisotropic stress states are investigated using a coupled DEM(distinct element method)and DFN(discrete fracture network)method.It provides estimates of the effect of fracture strength weakening,wellbore pressure,in situ stresses,and sealing efficiency on borehole stability.The results show that mud intrusion and weakening of fracture strength can damage the borehole.This is demonstrated by the large displacement around the borehole,shear displacement on natural fractures,and the generation of fracture at shear limit.Mud intrusion reduces the shear strength of the fracture surface and leads to shear failure,which explains that the increase in mud weight may worsen borehole stability during overbalanced drilling in fractured formations.A higher in situ stress anisotropy exerts a significant influence on the mechanism of shear failure distribution around the wellbore.Moreover,the effect of sealing natural fractures on maintaining borehole stability is verified in this study,and the increase in sealing efficiency reduces the radial invasion distance of drilling mud.This study provides a directly quantitative prediction method of borehole instability in naturally fractured formations,which can consider the discrete fracture network,mud intrusion,and associated weakening of fracture strength.The information provided by the numerical approach(e.g.displacement around the borehole,shear displacement on fracture,and fracture at shear limit)is helpful for managing wellbore stability and designing wellbore-strengthening operations.

Numerical and theoretical study of large-scale failure of strata overlying sublevel caving mines with steeply dipping discontinuities

The deformation and fracture evolution mechanisms of the strata overlying mines mined using sublevel caving were studied via numerical simulations.Moreover,an expression for the normal force acting on the side face of a steeply dipping superimposed cantilever beam in the surrounding rock was deduced based on limit equilibrium theory.The results show the following:(1)surface displacement above metal mines with steeply dipping discontinuities shows significant step characteristics,and(2)the behavior of the strata as they fail exhibits superimposition characteristics.Generally,failure first occurs in certain superimposed strata slightly far from the goaf.Subsequently,with the constant downward excavation of the orebody,the superimposed strata become damaged both upwards away from and downwards toward the goaf.This process continues until the deep part of the steeply dipping superimposed strata forms a large-scale deep fracture plane that connects with the goaf.The deep fracture plane generally makes an angle of 12°-20°with the normal to the steeply dipping discontinuities.The effect of the constant outward transfer of strata movement due to the constant outward failure of the superimposed strata in the metal mines with steeply dipping discontinuities causes the scope of the strata movement in these mines to be larger than expected.The strata in the metal mines with steeply dipping discontinuities mainly show flexural toppling failure.However,the steeply dipping structural strata near the goaf mainly exhibit shear slipping failure,in which case the mechanical model used to describe them can be simplified by treating them as steeply dipping superimposed cantilever beams.By taking the steeply dipping superimposed cantilever beam that first experiences failure as the key stratum,the failure scope of the strata(and criteria for the stability of metal mines with steeply dipping discontinuities mined using sublevel caving)can be obtained via iterative computations from the key stratum,moving downward toward and upwards away from the goaf.

FUNDAMENTAL RIGHTS IN THE DIGITAL ERA, HORIZONTAL EFFECT AND THE DISTINCTION BETWEEN ＂STATE＂ AND ＂SOCIETY＂ IN GERMAN AND EUROPEAN CONSTITUTIONAL THEORY

The article discusses the proposal for a ＂Charter of Digital Fundamental Rights of the European Union,＂ whose central element is a binding effect of its fundamental rights not only to state authorities, but also to powerful private intemet companies, which have a potential similar to that of the state to infringe on fundamental rights in the digital era. The article outlines the traditional German approach to fundamental rights and its underlying distinction between state and society, which makes it difficult for German scholars to handle a so-called horizontal effect of fundamental rights. Finally, the article discusses the main objections to such a horizontal effect and shows some practical problems it has the potential to cause in German and European constitutional law.

IMPLICATIONAL RELATION AND PERCEPTUAL DISTINCTION:A CASE STUDY ON PLACE CONTRASTS OF FRICATIVES VS. AFFRICATES

A typological survey across Chinese dialects reveals that,in the[i]context,the place contrasts of dental vs.palatal affricates(i.e.,[tsi-t■i]and[ts^(h)i-t■^(h)i])imply the place contrast of fricatives(i.e.,[si-■i]).Assuming a connection between the implicational relation of phonological contrasts and perceptual distinction,this study examines the relative perceptual distinction of the sound pairs[tsi-t■i][ts^(h)i-t■^(h)i]and[si-■i]through a speeded-AX discrimination experiment.The results showed that the discrimination accuracy of the[tsi-t■i]and[ts^(h)i-t■^(h)i]pairs is significantly lower than that of the[si-■i]pair,indicating that the former two pairs are perceptually less distinct than the latter pair.The results lend support to the contention that a sound pair in the unmarked category tends to be perceptually more distinct than its counterpart in a marked category.

Automatic identification of rock discontinuity and stability analysis of tunnel rock blocks using terrestrial laser scanning

Local geometric information and discontinuity features are key aspects of the analysis of the evolution and failure mechanisms of unstable rock blocks in rock tunnels.This study demonstrates the integration of terrestrial laser scanning(TLS)with distinct element method for rock mass characterization and stability analysis in tunnels.TLS records detailed geometric information of the surrounding rock mass by scanning and collecting the positions of millions of rock surface points without contact.By conducting a fuzzy K-means method,a discontinuity automatic identification algorithm was developed,and a method for obtaining the geometric parameters of discontinuities was proposed.This method permits the user to visually identify each discontinuity and acquire its spatial distribution features(e.g.occurrences,spac-ings,trace lengths)in great detail.Compared with hand mapping in conventional geotechnical surveys,the geometric information of discontinuities obtained by this approach is more accurate and the iden-tification is more efficient.Then,a discrete fracture network with the same statistical characteristics as the actual discontinuities was generated with the distinct element method,and a representative nu-merical model of the jointed surrounding rock mass was established.By means of numerical simulation,potential unstable rock blocks were assessed,and failure mechanisms were analyzed.This method was applied to detection and assessment of unstable rock blocks in the spillway and sand flushing tunnel of the Hongshiyan hydropower project after a collapse.The results show that the noncontact detection of blocks was more labor-saving with lower safety risks compared with manual surveys,and the stability assessment was more reliable since the numerical model built by this method was more consistent with the distribution characteristics of actual joints.This study can provide a reference for geological survey and unstable rock block hazard mitigation in tunnels subjected to complex geology and active rockfalls.

Effects of intermediate stress on deep rock strainbursts under true triaxial stresses

The effect of intermediate stress(in situ tunnel axial)on a strainburst is studied with a threedimensional(3D)bonded block distinct element method(DEM).A series of simulations of strainbursts under true triaxial in situ stress conditions(i.e.high tangential stress,moderate intermediate stress and low radial stress)of near-boundary rock masses are performed.Compared with the experimental results,the DEM model is able to capture the stress-strain response,failure pattern and energy balance of strainbursts.The fracturing processes of strainbursts are also numerically reproduced.Numerical results show that,as the intermediate stress increases:(1)The peak strain of strainbursts increases,the yield stress increases,the rock strength increases linearly,and the ratio of yield stress to rock strength decreases,indicating that the precursory information on strainbursts is enhanced;(2)Tensile and shear cracks increase significantly,and slabbing and bending of rock plates are more pronounced;and(3)The stored elastic strain energy and dissipated energy increase linearly,whereas the kinetic energy of the ejected rock fragments increases approximately exponentially,implying an increase in strainburst intensity.By comparing the experimental and numerical results,the effect of intermediate stress on the rock strength of strainbursts is discussed in order to address three key issues.Then,the Mogi criterion is applied to construct new strength criteria for strainbursts by converting the one-face free true triaxial stress state of a strainburst to its equivalent true triaxial stress state.In summary,the effect of intermediate stress on strainbursts is a double-edged sword that can enhance the rock strength and the precursory information of a strainburst,but also increase its intensity.

Investigation of long-wavelength elastic wave propagation through wet bentonite-filled rock joints

The saturation of the compacted bentonite buffer in the deep geological repository can cause bentonite swelling,intrusion into rock fractures,and erosion.Inevitably,erosion and subsequent bentonite mass loss due to groundwater inflow can aggravate the overall integrity of the engineered barrier system.Therefore,the coupled hydro-mechanical interaction between the buffer and rock during groundwater inflow and bentonite intrusion should be evaluated to guarantee the long-term safety of deep geological disposal.This study investigated the effect of bentonite erosion and intrusion on the elastic wave propagation characteristics in jointed rocks using a quasi-static resonant column test.Jointed rock specimens with different joint conditions(i.e.joint surface saturation and bentonite filling)were prepared using granite rock discs sampled from the Korea Underground Research Tunnel(KURT)and Gyeongju bentonite.The long-wavelength longitudinal and shear wave velocities were measured under different normal stress levels.A Hertzian-type power model was used to fit the wave velocities,and the relationship between the two fitted parameters provided the trend of joint conditions.Numerical simulations using three-dimensional distinct element code(3DEC)were conducted to better understand how the long-wavelength wave propagates through wet bentonite-filled rock joints.

Impact of ICTs on Core Competences of SMEs in Bukavu, DRC

Currently, it has been noticed a strong use of ICTs in several companies. The objective of this study was to analyze and measure the impact of the implementation of ICTs on the strategy and structure of management of core competence in SMEs in Bukavu, DRC. The scale used shows the good psychometric properties (χ2 = 75.045;P = 0.16;χ2/ddl = 1.471;CFI = 0.92;IFI = 0.92;RMSEA = 0.049;NFI = 0.79;GFI = 0.94;AGFI = 0.91. This study analyzed primary data collected from 195 SMEs in the city of Bukavu. Data processing was achieved using exploratory and confirmatory factor analysis and flat sorting. The results indicate that the use of ICTs by SME managers in the city of Bukavu has a positive impact on all dimensions of core competence selected in this study. They also reveal that the views of these leaders on the importance attached to the adoption of ICTs were divided and the level of ICT use was above average.

A Brief Account of Independent College in China:Its Past and Further Development

This article briefs the past and development of independent colleges until now in China,dealing with the reasons why they have come into existence and developed in a remarkable way.A somewhat detailed analysis of their distinctions from other higher education has been made and the further development strategies are also presented in it.

On the Contrastive Analysis between China English and Chinglish

The paper attempts to make the distinction between China English and Chinglish from the different aspects,to understandmore about the relationship of them and reasons of their occurrences.With a synthesizing and comparative method,the study draws aclear cut between China English and Chinglish and explores their implications to EFL in China.

采动影响下山区地表裂隙发育通用离散单元法模拟研究

贵州响水煤矿3#煤层12309回采工作面停采后,离工作面较近地表未发现裂隙,远离工作面地表反而出现明显裂隙,针对这一现象,运用UDEC软件对12309采面进行了仿真数值模拟实验,通过模拟实验得到:采深172 m的开切眼前后出现两组裂隙,裂隙呈"V"字形;停采线处,水平离层裂隙和竖向破断裂隙贯通至地表冲沟;变坡面裂隙发育,稳定性差,会发生滑坡。

Effective source rock selection and oil–source correlation in the Western Slope of the northern Songliao Basin,China

This study considers the Upper Cretaceous Qingshankou Formation,Yaojia Formation,and the first member of the Nenjiang Formation in the Western Slope of the northern Songliao Basin.Dark mudstone with high abundances of organic matter of Gulong and Qijia sags are considered to be significant source rocks in the study area.To evaluate their development characteristics,differences and effectiveness,geochemical parameters are analyzed.One-dimensional basin modeling and hydrocarbon evolution are also applied to discuss the effectiveness of source rocks.Through the biomarker characteristics,the source–source,oil–oil,and oil–source correlations are assessed and the sources of crude oils in different rock units are determined.Based on the results,Gulong and Qijia source rocks have different organic matter primarily detrived from mixed sources and plankton,respectively.Gulong source rock has higher thermal evolution degree than Qijia source rock.The biomarker parameters of the source rocks are compared with 31 crude oil samples.The studied crude oils can be divided into two groups.The oil–source correlations show that group I oils from Qing II–III,Yao I,and Yao II–III members were probably derived from Gulong source rock and that only group II oils from Nen I member were derived from Qijia source rock.