基于Reason模型的SIF-Q260型电子小肠镜故障原因分析

根据武汉大学中南医院内窥镜中心SIF-Q260型小肠镜故障率高且维修成本高的情况,应用Reason模型,从环境影响、不安全监督、不安全行为前兆及不安全行为4个层面分析造成SIF-Q260小肠镜故障的原因,针对各个层面故障原因,从定期培训以规范内窥镜的洗消及使用、设置专人管理内窥镜并定期对内窥镜使用洗消的规范性进行监督及评价、完善内窥镜监管系统3方面拟定改进措施,堵住系统“漏洞”,为内窥镜质量控制措施的制定提供依据,可预防和减少内窥镜故障的发生。

Temperature-Triggered Hardware Trojan Based Algebraic Fault Analysis of SKINNY-64-64 Lightweight Block Cipher

SKINNY-64-64 is a lightweight block cipher with a 64-bit block length and key length,and it is mainly used on the Internet of Things(IoT).Currently,faults can be injected into cryptographic devices by attackers in a variety of ways,but it is still difficult to achieve a precisely located fault attacks at a low cost,whereas a Hardware Trojan(HT)can realize this.Temperature,as a physical quantity incidental to the operation of a cryptographic device,is easily overlooked.In this paper,a temperature-triggered HT(THT)is designed,which,when activated,causes a specific bit of the intermediate state of the SKINNY-64-64 to be flipped.Further,in this paper,a THT-based algebraic fault analysis(THT-AFA)method is proposed.To demonstrate the effectiveness of the method,experiments on algebraic fault analysis(AFA)and THT-AFA have been carried out on SKINNY-64-64.In the THT-AFA for SKINNY-64-64,it is only required to activate the THT 3 times to obtain the master key with a 100%success rate,and the average time for the attack is 64.57 s.However,when performing AFA on this cipher,we provide a relation-ship between the number of different faults and the residual entropy of the key.In comparison,our proposed THT-AFA method has better performance in terms of attack efficiency.To the best of our knowledge,this is the first HT attack on SKINNY-64-64.

A Comparative Analysis of the New -3(-n) - 1 Remer Conjecture and a Proof of the 3n + 1 Collatz Conjecture

This scientific paper is a comparative analysis of two mathematical conjectures. The newly proposed -3(-n) - 1 Remer conjecture and how it is related to and a proof of the more well known 3n + 1 Collatz conjecture. An overview of both conjectures and their respective iterative processes will be presented. Showcasing their unique properties and behavior to each other. Through a detailed comparison, we highlight the similarities and differences between these two conjectures and discuss their significance in the field of mathematics. And how they prove each other to be true.

Analysis on the Reason of Local Heavy Rainstorm Forecast Error in the Subtropical High Control

[Objective] The research aimed to study the reason of local heavy rainstorm forecast error in the subtropical high control. [Method] Started from summarizing the reason of forecast error, by using the conventional ground observation data, the upper air sounding data, T639, T213 and European Center (ECMWF) numerical prediction product data, GFS precipitation forecast product of U.S. National Center for Environmental Prediction, the weather situation, physical quantity field in a heavy rainstorm process which happened in the north of Shaoyang at night on August 5, 2010 were fully analyzed. Based on the numerical analysis forecast product data, the reason of heavy rainstorm forecast error in the subtropical high was comprehensively analyzed by using the comparison and analysis method of forecast and actual situation. [Result] The forecasters didn’t deeply and carefully analyze the weather situation. On the surface, 500 hPa was controlled by the subtropical high, but there was the weak shear line in 700 and 850 hPa. Moreover, they neglected the influences of weak cold air and easterlies wave. The subtropical high quickly weakened, and the system adjustment was too quick. The wind field variations in 850, 700 and 500 hPa which were forecasted by ECMWF had the big error with the actual situation. It was by east about 2 longitudes than the actual situation. In summer forecast, they only considered the intensity and position variations of 500 hPa subtropical high, and neglected the situation variations in the middle, low levels and on the ground. It was the most key element which caused the rainstorm forecast error in the subtropical high. The forecast error of numerical forecast products on the height field situation variation was big. The precipitation forecasts of Japan FSAS, U.S. National Center for Environmental Prediction GFS, T639 and T213 were all small. The humidity field forecast value of T639 was small. In the rainstorm forecast, the local rainstorm forecast index and method weren’t used in the forecast practice. In the precipitation forecast process, they only paid attention to the score prediction of station and didn’t value the non-site prediction. Some important physical quantity factors weren’t carefully studied. [Conclusion] The research provided the reference basis for the forecast and early warning of local heavy rainstorm.

Milling Fault Detection Method Based on Fault Tree Analysis and Hierarchical Belief Rule Base

Expert knowledge is the key to modeling milling fault detection systems based on the belief rule base.The construction of an initial expert knowledge base seriously affects the accuracy and interpretability of the milling fault detection model.However,due to the complexity of the milling system structure and the uncertainty of the milling failure index,it is often impossible to construct model expert knowledge effectively.Therefore,a milling system fault detection method based on fault tree analysis and hierarchical BRB(FTBRB)is proposed.Firstly,the proposed method uses a fault tree and hierarchical BRB modeling.Through fault tree analysis(FTA),the logical correspondence between FTA and BRB is sorted out.This can effectively embed the FTA mechanism into the BRB expert knowledge base.The hierarchical BRB model is used to solve the problem of excessive indexes and avoid combinatorial explosion.Secondly,evidence reasoning(ER)is used to ensure the transparency of the model reasoning process.Thirdly,the projection covariance matrix adaptation evolutionary strategies(P-CMA-ES)is used to optimize the model.Finally,this paper verifies the validity model and the method’s feasibility techniques for milling data sets.

Integrated use of GIS, remote sensing and multi-criteria decision analysis to assess ecological land suitability in multi-functional forestry

The Zagros forests are a treasure of valuable oak forests, but they have been severely degraded from long-term misuse. Geographic information systems （GIS） and multi-criteria decision analysis （MCDA） have been increasingly used to improve the management of vulnerable ecosystems to prevent further degradation and increase the sustainability of land use. This study presents a methodology to assess land suitability using remote sensing （RS） to obtain wall-to-wall data for the calculations, GIS to analyze the data, and MCDA to rank alternative land uses. The criteria and subcriteria affecting the suitability of land for different uses were identified and weighted using an analytic hierarchy process. Variables used as subcriteria were assessed using satellite data and other sources of information such as existing maps and field surveys. Numerical values for the subcriteria were classified, and each class was given a priority rating according to expert judgments. Based on the ratings and weights of the subcriteria, a priority map was created for each land use using the weighted linear combination method. The priority maps for different land uses were overlaid to obtain a preliminary land use map, which often indicated several simultaneous land uses for the same location. The preliminary map was further edited by removing unrealistic, mutually exclusive land-use combinations. The study tested and demonstrated the potential of integrating RS, G1S and MCDA techniques for solving complicated land allocation problems in forested regions using a scientifically sound and practical approach for efficient and sustainable allocation of forestland for different uses.

A Processor Performance Prediction Method Based on Interpretable Hierarchical Belief Rule Base and Sensitivity Analysis

The prediction of processor performance has important referencesignificance for future processors. Both the accuracy and rationality of theprediction results are required. The hierarchical belief rule base (HBRB)can initially provide a solution to low prediction accuracy. However, theinterpretability of the model and the traceability of the results still warrantfurther investigation. Therefore, a processor performance prediction methodbased on interpretable hierarchical belief rule base (HBRB-I) and globalsensitivity analysis (GSA) is proposed. The method can yield more reliableprediction results. Evidence reasoning (ER) is firstly used to evaluate thehistorical data of the processor, followed by a performance prediction modelwith interpretability constraints that is constructed based on HBRB-I. Then,the whale optimization algorithm (WOA) is used to optimize the parameters.Furthermore, to test the interpretability of the performance predictionprocess, GSA is used to analyze the relationship between the input and thepredicted output indicators. Finally, based on the UCI database processordataset, the effectiveness and superiority of the method are verified. Accordingto our experiments, our prediction method generates more reliable andaccurate estimations than traditional models.

Symplectic analysis for elastic wave propagation in two-dimensional cellular structures

On the basis of the finite element analysis, the elastic wave propagation in cellular structures is investigated using the symplectic algorithm. The variation principle is first applied to obtain the dual variables and the wave propagation problem is then transformed into two-dimensional （2D） symplectic eigenvalue problems, where the extended Wittrick-Williams algorithm is used to ensure that no phase propagation eigenvalues are missed during computation. Three typical cellular structures, square, triangle and hexagon, are introduced to illustrate the unique feature of the symplectic algorithm in higher-frequency calculation, which is due to the conserved properties of the structure-preserving symplectic algorithm. On the basis of the dispersion relations and phase constant surface analysis, the band structure is shown to be insensitive to the material type at lower frequencies, however, much more related at higher frequencies. This paper also demonstrates how the boundary conditions adopted in the finite element modeling process and the structures＇ configurations affect the band structures. The hexagonal cells are demonstrated to be more efficient for sound insulation at higher frequencies, while the triangular cells are preferred at lower frequencies. No complete band gaps are observed for the square cells with fixed-end boundary conditions. The analysis of phase constant surfaces guides the design of 2D cellular structures where waves at certain frequencies do not propagate in specified directions. The findings from the present study will provide invaluable guidelines for the future application of cellular structures in sound insulation.

Algebraic Solution for the Forward Displacement Analysis of the General 6-6 Stewart Mechanism

The solution for the forward displacement analysis（FDA） of the general 6-6 Stewart mechanism（i.e., the connection points of the moving and fixed platforms are not restricted to lying in a plane） has been extensively studied, but the efficiency of the solution remains to be effectively addressed. To this end, an algebraic elimination method is proposed for the FDA of the general 6-6 Stewart mechanism. The kinematic constraint equations are built using conformal geometric algebra（CGA）. The kinematic constraint equations are transformed by a substitution of variables into seven equations with seven unknown variables. According to the characteristic of anti-symmetric matrices, the aforementioned seven equations can be further transformed into seven equations with four unknown variables by a substitution of variables using the Grobner basis. Its elimination weight is increased through changing the degree of one variable, and sixteen equations with four unknown variables can be obtained using the Grobner basis. A 40th-degree univariate polynomial equation is derived by constructing a relatively small-sized 9 × 9 Sylvester resultant matrix. Finally, two numerical examples are employed to verify the proposed method. The results indicate that the proposed method can effectively improve the efficiency of solution and reduce the computational burden because of the small-sized resultant matrix.

Numerical Analysis of the Adhesive Forces in Nano-Scale Structure

Nanohairs, which can be found on the epidermis of Tokay gecko＇s toes, contribute to the adhesion by means of van der Waals force, capillary force, etc. This structure has inspired many researchers to fabricate the attachable nano-scale structures. However, the efficiency of artificial nano-scale structures is not reliable sufficiently. Moreover, the mechanical parameters related to the nano-hair attachment are not yet revealed qualitatively. The mechanical parameters which have influence on the ability of adhesive nano-hairs were investigated through numerical simulation in which only van der Waals force was considered. For the numerical analysis, finite element method was utilized and van der Waals force, assumed as 12-6 Lennard-Jones potential, was implemented as the body force term in the finite element formulation.

Research on Loose Reason of Fixing Bolt of Step Connector based on Finite Element Analysis

There are two connection modes between escalator step and step drive chain of outer roller,connector type A and type B.Connector type B after a period of running was found that the fixing bolt on the connector has loosened,which causes safety risks.In order to eliminate this security issue,the finite element modeling is proposed to analyze the relationship between the force generated by the connector type A or type B during the step band running and the assembly clearance or the assembly mode.So as to find out the root cause of fixing bolt loosening phenomenon,by redesigning the assembly clearance between the connector shaft and the chain hole,the fixing bolt of the connector is prevented from loosening during the step band running,ensuring the safe operation of escalators to avoid injury accidents.

Formation Reason Analysis and Defense Countermeasure of Rare Frozen Disaster in Guizhou in 2008

[Objective] The research aimed to discuss the formation reason of low temperature and frozen disaster weather event in Guizhou in 2008.[Method] By using T213,ECMWF numerical forecast data and the conventional meteorological observation data which were provided by MICAPS,according to the variation situations of frozen rain,freezing,road freezing and ground surface 0 ℃ line range,the weather situation evolution characteristic of low temperature and frozen weather process (congelation for short) in Guizhou from January 13 to February 15,2008 was analyzed.The formation reason of low temperature and frozen disaster weather event in Guizhou was discussed,and the defense countermeasure was put forward.[Result] The low temperature and frozen weather process happened when the continuous precipitation was caused by that every scale weather system intersected in Guizhou under the abnormal atmospheric circulation background.East Asian inverted Ω flow type in the northern hemisphere made that the atmospheric circulation stabilized for a long time,and the north branch frontal zone was by south.The polar cold air continued to complement and went south to affect Jiangnan,South China.The south branch westerly fluctuation was active,and the frontal zone intensity of stationary front was big,which maintained for a long time.850 hPa shear line in the low level maintained to swing in the junction of Guangxi and Guizhou,Hunan.The southwest warm and wet airflow continued transporting to the south of China.The cold and warm air intersected in South China,which caused the long-time precipitation in Guizhou.The thermal inversion layer was deep and thick.The long-time precipitation based generally on the light rain.It was easy to form the supercooled water droplet.The verglas range expanded from Guizhou,the south of Hunan to the north of Guangxi.The frozen rain and frozen weather caused the long-time road and wire freezing.The disaster was serious.The ground surface temperature 0 ℃ line covered the cold mountain area in the whole province for a long time.The ground surface freezing was difficult to melt,and the low temperature and frozen weather affected Guizhou for a long time.[Conclusion] The research accumulated the experience for the disaster prevention and reduction of such weather.

Analysis on Formation Reason of a Local Heavy Rainstorm in Linyi Area

[Objective] The research aimed to study formation reason of a local heavy rainstorm process in Linyi from night on August 3 to early morning on 4th, 2010. [Method] Based on MICAPS weather chart, actual situation data of NECP analysis field, data of automatic encryption station and Doppler radar product, a local heavy rainstorm and extra heavy rainstorm process in Linyi from night on August 3 to early morning on 4th, 2010 was detailedly analyzed from weather background, meso- and micro-scale characteristics, physical mechanisms of occurrences and developments of meso and micro-scale systems. The formation reason of heavy rainstorm process was discussed. Moreover, we tried to find some occurrence rules of short-time strong precipitation. [Result] The local heavy rainstorm process had large short-time rainfall and obvious local characteristics. The main influence systems were subtropical high, westerly trough, meso- and small-scale ground low pressures. It was affected by many systems which had different scales and heights. The up-cold-down-warm unstable stratification accumulated a large number of unstable energy, which was basic condition of strong precipitation occurrence. It was convergence shear line at the bottom layer of airspace. The vertical shear and turbosphere of deep southwest-northwest-easterly airflow were at airspace. The common effect of up and down systems triggered generation of updraft, and made unstable energy release. For the release of unstable energy, after northwest airflow was cut off, the updraft made southwest airflow develop upward. It linked with easterly wave to form new vertical shear, which was a reason of long duration of strong precipitation. The southwest airflow at the edge of subtropical high was water vapor source of precipitation process, which provided sufficient water vapor supply for generation of heavy rainstorm. The system which was developing and strengthening would make the moving speed of system slow down. Then, the rainfall increased. It was a reason of long duration of strong precipitation. [Conclusion] The research accumulated certain experience for forecast work in future.

Analysis on the Influence of Spring Low Temperature on the Agriculture and the Formation Reason in Liaoning Province in 2010

[Objective] The research aimed to study the influence of spring low temperature on the agriculture and the formation reason in Liaoning Province in 2010. [Method] Based on the synoptics analysis principle, by analyzing the atmospheric circulation situation and satellite cloud map, the influence of spring low temperature on the agriculture and the formation reason of low temperature weather in Liaoning Province during April-May, 2010 were discussed. [Result] The high-altitude situation analysis showed that it was two-trough-two-ridge situation in the high latitude of Eurasia in April, 2010. Ural Mountains high-pressure ridge strengthened to move eastward. Lake Baikal cold air went down toward the southeast along the front of ridge and strengthened into the cold vortex. Liaoning was in the front of cold vortex. Affected by the cold vortex, the temperature in Liaoning area was low. In the first dekad of May, 2010, the activity of cold air was frequent. There were two times cold vortex influence, and the temperature was still low. In the later period of middle dekad of May, the warm ridge entered, and the temperature rose. The high-altitude trough and the low-level jet were the main system and the dynamic condition of precipitation generation respectively. The cold vortex was the main reason of spring continuous low temperature generation, and the secondary reason was the more precipitation. [Conclusion] The research provided the reference basis for the prevention and prediction of spring low temperature in Liaoning Province.

Analysis on Formation Reason of "0902" Blizzard in Northeast China

[Objective]The research aimed to analyze formation reason of ＂ 0902＂ blizzard in northeast China. [Method]By using timely observation data,NCEP reanalysis data and Doppler radar data at Baishan station,blizzard process in southeast part of northeast China during 12-13 February,2009 was analyzed. [Result]Snowfall zone of the blizzard process was wide,snowfall was more,snowfall gradient was big,and snowfall time relatively concentrated. These characteristics reflected that the blizzard process had significant convection characteristics. Baroclinic disturbance at high-altitude straight frontal zone and ground warm frontogenesis caused by eastward movement and northward advancement of North China low vortex at low altitude were the circulation characteristics in the process. Water vapor from the sea went northward as southwest airflow,and strongly converged in blizzard zone,which provided sufficient water vapor condition for the blizzard. Before heavy snowfall occurred,there was accumulation process of heat and energy. Conditional symmetric instability was main unstable mechanism of the blizzard. During heavy snowfall period,ascending branch of secondary vertical circulation at exit zone of high-altitude jet coupled with ascending branch of secondary vertical circulation of warm frontegenesis at low layer,inducing strong development of the vertical motion. Doppler radar intensity echo revealed that it was easy to generate blizzard in the area where echo intensity was consistently above 20 dBz. Strong wind velocity convergence zone at radical velocity field especially adverse wind zone was favorable for the generation of blizzard. [Conclusion]The research could provide reference for blizzard forecast in northeast China.

Multi-genome evolutionary study of the ABC1 gene family and identification of the pleiotropic effects of OsABC1-13 in rice development

In four rice genomes,85 ABC1-family genes were identified by comparative genomics,evolution,genetics,and physiology.One,OsABC1-13,was shown by knockdown and knockout experiments to affect plant height,grain size,and photosynthetic capability.

Multiple Regression Analysis of Influencing Factors on Yield of New Sugarcane Variety Yuetang 03-373

[Objectives]The purpose of this study was to provide reference for cultivation and promotion of a new sugarcane variety Yuetang 03-373,on the basis of analyzing and summarizing the characters of the variety.[Methods]Correlation,multiple regression and path analyses were performed for the yield and yield components of Yuetang 03-373.[Results]Correlation analysis shows that cane yield was significantly correlated with millable stalk number,stalk length and stalk diameter,and among them,the correlation with millable stalk number was the strongest.Multiple regression and path analyses show that millable stalk number contributed the most to cane yield,followed by stalk length,and stalk diameter contributed the least.The regression equation of cane yield against the three yield components was y=-2.8713+1.5497x1+5.8990x2-395.4294x3(R=0.9672**).[Conclusions]Millable stalk number and stalk length were the important and major factors for high yield of Yuetang 03-373,indicating that Yuetang 03-373 is a sugarcane variety of millable stalk type.In cultivation,full play should be given to the advantage of Yuetang 03-373 in millable stalk number,as well as stalk length(plant height),in order to achieve the purpose of increasing yield.

A search for evidence of small-scale inhomogeneities in dense cores from line profile analysis

In order to search for intensity fluctuations on the HCN（1-0） and HCO＋（1-0） line pro- files, which could arise due to possible small-scale inhomogeneous structure, long-term observations of high-mass star-forming cores S140 and S199 were carried out. The data were processed by the Fourier filtering method. Line temperature fluctuations that exceed the noise level were detected. Assuming the cores consist of a large number of randomly moving small thermal fragments, the total number of frag- ments is - 4 × 106 for the region with linear size - 0.1 pc in S140 and - 106 for the region with linear size - 0.3 pc in S 199. Physical parameters of fragments in S 140 were obtained from detailed modeling of the HCN emission in the framework of the clumpy cloud model.

An analysis on El Nino processes during 1949-1987

-In this paper, the outset, evolution and intensity of El Nino were analyzed. Different features were found in each El Nino process. The El Nino of 1986 was also analyzed and outlined.

Entropy Analysis of Vapor-Compression Refrigeration System by Using the Second Law of Thermodynamics

By means of the Second Law of Thermodynamics,thispaper gives out the entropy analysis method for vapor-comperession refrigeration system.The thermal irrevers-ibility of the system charged with R12 and its hopeful al-ternative refrlgerant R134a have been studied respective-ly.On the basis of all the research results of this paper,the measure used to save energy for vapor-compressionrefrigeration system has been put out.