3D limit analysis of rock slopes based on equivalent linear failure criterion with tension cut-off

Hoek-Brown (HB) failure criterion is widely used to predict the strength of intact or heavily jointed rock mass. For stability analysis of rock slopes governed by the HB failure criterion, the equivalent linearity to Mohr-Coulomb (MC) criterion is often adopted, leading to the well-known equivalent Mohr-Coulomb method (EMCM). Existing studies on EMCM analysis mainly consider the shear strength of rock material, while consideration of the tensile strength is rare. This contradicts the fact that the underlying tensile strength of rock mass has considerable impact on the rock slope stability in real world. In this regard, this paper proposes a limit analysis-based approach that can account for tension in the three-dimensional (3D) stability analysis of HB rock slope. This approach is established on the equivalent linearity of the HB criterion with consideration of tensile strength, known as the equivalent tension cut-off MC method (ETMCM), and using a horn-like 3D mechanism of limit analysis. The safety factor solutions given by the proposed approach are validated by previous studies and numerical results. Parametric studies are conducted to investigate the effect of rock tensile strength on slope stability. Results show that the consideration of tension leads to a more conservative safety factor and a sharper curvature of the failure surface, and these impacts tend to be more obvious with the increases in slope inclination and slope width. Finally, the stability of the HB rock slope under seepage conditions is studied using the proposed approach. The results indicate that the effect of tensile strength is highly remarkable in seepage circumstances.

Genetic parameters estimation for growth traits in cultured tiger pufferfish(fugu),Takifugu rubripes

The aim of this study was to evaluate the genetic parameters of the growth performance of Takifugu rubripes.Heritabilities and genetic correlations were estimated for body weight(BW),body length(BL),total length(TL),chest measurement(CM)and trunk length(TKL)of T.rubripes from measurements of progeny at 6 months and 12 months.The results showed that the heritability was 0.37 for BW6,0.19 for BL6,0.35 for TL6,0.29 for CM6,0.26 for TKL6,0.36 for BW12,0.26 for BL12,0.25 for TL12,0.31 for CM12 and 0.15 for TKL12.The range of genetic correlations estimated at 6 months was 0.025–0.725 and−0.002–0.706 at 12 months.The results indicated that genetic improvement for faster growth rate or increased body weight in cultured T.rubripes was effective.Based on selection theory,the selection strategy for traits with medium heritability is flexible.Considering that these growth traits do not reach the high level of heritability,family selection should be expected.Given positive genetic correlations among BW,BL,TL,CM,and TKL at 6 months,the five traits could be improved simultaneously through selective breeding.As there was high genetic correlation only between BW12,BL12 and TL12,and negative correlations between TKL12 and BL12 as well as between CM12 and TL12,and only BW,BL and TL at 12 months could be improved simultaneously.

A Novel Semi-Quantum Private Comparison Scheme Using Bell Entangle States

Private comparison is the basis of many encryption technologies,and several related Quantum Private Comparison(QPC)protocols have been published in recent years.In these existing protocols,secret information is encoded by using conjugate coding or orthogonal states,and all users are quantum participants.In this paper,a novel semi-quantum private comparison scheme is proposed,which employs Bell entangled states as quantum resources.Two semi-quantum participants compare the equivalence of their private information with the help of a semi-honest third party(TP).Compared with the previous classical protocols,these two semi-quantum users can only make some particular action,such as to measure,prepare and reflect quantum qubits only in the classical basis fj0i;j1ig,and TP needs to perform Bell basis measurement on reflecting qubits to obtain the results of the comparison.Further,analysis results show that this scheme can avoid outside and participant attacks and its’qubit efficiency is better than the other two protocols mentioned in the paper.

Quantum Secure Direct Communication Protocol with Mutual Authentication Based on Single Photons and Bell States

Quantum secure direct communication(QSDC)can transmit secret messages directly from one user to another without first establishing a shared secret key,which is different from quantum key distribution.In this paper,we propose a novel quantum secure direct communication protocol based on signal photons and Bell states.Before the execution of the proposed protocol,two participants Alice and Bob exchange their corresponding identity IDA and IDB through quantum key distribution and keep them secret,respectively.Then the message sender,Alice,encodes each secret message bit into two single photons(|01>or|10>)or a Bell state(1|φ^(+)>=1/√2(|0>|-|1>1>)),and composes an ordered secret message sequence.To insure the security of communication,Alice also prepares the decoy photons and inserts them into secret message sequence on the basis of the values of IDA and IDB.By the secret identity IDA and IDB,both sides of the communication can check eavesdropping and identify each other.The proposed protocol not only completes secure direct communication,but also realizes the mutual authentication.The security analysis of the proposed protocol is presented in the paper.The analysis results show that this protocol is secure against some common attacks,and no secret message leaks even if the messages are broken.Compared with the two-way QSDC protocols,the presented protocol is a one-way quantum communication protocol which has the immunity to Trojan horse attack.Furthermore,our proposed protocol can be realized without quantum memory.

Comparison of Rapid Freezing and Vitrification for Human Sperm Cryopreservation Using Trehalose as a Cryoprotective Agent

Rapid freezing and vitrification are becoming popular for human sperm cryopreservation;however, it remains unclear which method is better. The aims of the present study were to determine the optimal trehalose concentration and to compare the cryoprotective effects of rapid freezing and vitrification. The results showed that: 1) The optimal trehalose concentration was 0.25 mol/L;2) The post-thaw recovery rates of total and progressive sperm motilities after rapid freezing (38.6% ± 3.0% and 41.1% ± 5.0%) were significantly higher (P 0.05) than that after vitrification (26.1% ± 3.1% and 27.2% ± 1.3%) when 0.5 mL straws were used;3) However, the recovery rates of total and progressive motilities after rapid freezing in 0.5 mL straw (26.7% ± 9.6% and 26.8% ± 8.7%) were significantly lower (P 0.05) than that after vitrification in a novel straw-in-straw system (43.1% ± 4.2% and 41.8% ± 15.5%);and 4) The post-thaw sperm nuclear DNA damage level after rapid freezing in 0.5 mL straw (8.7% ± 2.8%) was not significantly different from that of sperm after vitrification in the straw-in-straw system (9.2% ± 2.5%). It was concluded that rapid freezing is superior to vitrification when using 0.5 mL straws;however, vitrification is superior to rapid freezing when using the straw-in-straw systems.

A new portable open-path instrument for ambient NH_(3) and on-road emission measurements

Increased attentions to vehicle emission of NH_(3)have been paid since it is generally regarded as an important source in urban areas.Here,we developed a movable instrument based on Differential Optical Absorption Spectroscopy(DOAS)principle for detecting on-road NH_(3),which can avoid the losses in the sampling process attributed to the non-sampling methods.For this mobile DOAS,the temporal resolution,detection limit and relative error for NH_(3)were 1 min,2.29 ppbv and 4.57%±2.44%,respectively.By employed to the on-road measurements along the arterial highway in Shanghai,the spatial distributions of NH_(3)and NO were obtained,and their dependence of traffic and road conditions were studied.The slopes of linear regression between NH_(3)and NO were 0.40,0.02 and 0.07 on the Middle Ring Road,Outer Ring Road and Chongming Island Ring Road.It indicates that light gasoline vehicles(LGVs)were found to be the main contributor to NH_(3)emissions,while heavy-duty diesel vehicles(HDVs)mainly emitted NO.Based on the measured NH_(3)in the tunnel,the mileagebased NH_(3)emission factor per vehicle was estimated to be 17.9±6.3 mg/km.The reported open-path instrument can be broadly used in on-road pollutant monitoring or vehicle emissions,and the measurements can reveal the real situation of emission characteristics,even find the abnormal operations of vehicle catalyst system.

Relationship between the temporal-spatial distribution of archaeological sites and natural environment from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area

The temporal-spatial distribution features including time distribution,horizontal and vertical spatial distribution of archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area are analyzed based on GIS spatial analysis.The successive pollen record of deposited peat stratum since the Paleolithic Age in the Dajiuhu Basin of Shennongjia is used in combination with the research of the historical environmental evolution to reconstruct the Paleoenvironment in the Three Gorges Reservoir of Chongqing area.Through the comparison of the temporal-spatial distribution of the archaeological sites and the natural environment,the relation between the distribution of the archaeological sites and the natural environment evolution and disaster changes from the Neolithic Age to the Tang and Song Dynasties has been discussed.Study shows that 677 archaeological sites from the Paleolithic Age to the Tang and Song Dynasties in the Three Gorges Reservoir of Chongqing area increase gradually from west to east and from high land to low land.Most of the sites are distributed along the river and aggregated at the confluence.Obviously,the altitudes of archaeological sites in the Paleolithic Age and the Neolithic Age are much higher than those of historical sites.The analysis suggests:(1)the human beings of every times would like to choose the first or the second river terrace as living sites which are nearer to the water source and are easier to with- stand flood.The pre-historical sites of earlier ages are often located at the higher altitude place because of the tectonic uplift and downcutting of rivers since Holocene.(2)Due to the rugged terrain in Chongqing area,most of the sites are located along the river sides,for example,the wide river valley and terrace,which could provide wider living space caused by the lateral erosion and deposition of the river course.(3)The early residents mainly relied on fishing,hunting and agriculture,and the rugged terrain of the mountainous area restricted the development of farming.However,in the confluence region,the fertilized plain provided an ideal location for farming and fishing.(4)The temporal-spatial distribution of archeological sites in this area is significantly affected by the climate condition.

Reconstructing past subsistence patterns on Zhongba Site using stable carbon and oxygen isotopes of fossil tooth enamel

The oxygen and carbon isotopic ratios in human and animal tooth enamel were measured to reconstruct the subsistence patterns on Zhongba Site between 2400 and 4200 aBP.The results indicate that human consumed chiefly C4 resources,such as millet,and the C3 plants,such as rice and wheat,constituted only a small fraction of the human diets,normally no more than 15%.There are significant differences in food sources between human and pig,and the percentages of C3 plants in pig diets were higher than those in human diets.But theδ13C values of pig partially overlap those of human,demonstrating some similarities in their food sources.The differences in water sources between human and pig are significant.There are significant differences in food and water sources between cattle and deer. This indicates that the two kinds of mammals subsisted in different niches.But theirδ13C values also partially overlap each other,suggesting some similarities in their food sources.There are both signifi- cant differences in meanδ13C andδ18O values between the omnivores,human and pig and the herbi- vores,cattle and deer,implying significant differences in food and water sources between the two categories.During the period the dietary habits of human had not changed,but the pig breeding strategies had changed,from breeding in house to breeding in confinement,and the proportion of C3 plants in pig food increased with time.The scope of human migration had been considerably large by the Warring States because of the development of productive forces.

Relations between man and nature reflected by the evolution of the Neolithic production tools in the Three Gorges region of Yangtze River,China

The relations between man and nature reflected by evolution of Neolithic production tools in the Three Gorges region of Yangtze River is discussed in this paper.Our results show that there is a good correlation between the percentage vibration of cutting tool types and the environmental evolution indicated by the natural profile nearby.It is possible for ancestors from the Three Gorges region to learn the advantage of mortise and tenon in the early Neolithic Age because they used the stones as vital tools for processing woods.The hunting method in the early Neolithic is throwing,which was inherited in the mid-Neolithic Age when hunting with arrow and bow was developed.Fishing tools are found at the same period.Numbers of net sinkers and spinning wheels unearthed from the strata of the Western Zhou Dynasty from Zhongba Site reveal the fact of fishing with net,while a mass of fishbone pits indi- cate the powerful productivity brought by new production tools.Quantity of stone spades and stone hoes proves that cultivation agriculture by hoe is extremely attached importance by the ancestors in the Three Gorges region.Moreover,the developed agriculture in Daxi Culture at Zhongbao Island benefits from the landform,climate,traffic location,etc.Otherwise,the reason that the farming tools declined in the late Neolithic Age is related to the extreme flood during the early Xia Dynasty and the fishing hunting preference of some ancient settlements.This research shows that ancestors of the Three Gorges region during the Neolithic Age attached importance to fish hunting and cultivation, fought against the natural environment by production tools,constantly created and improved them, then comprehensively utilized them to evolve the relations between man and nature.

Assimilation of atmospheric infrared sounder radiances with WRF-GSI for improving typhoon forecast

The Atmospheric Infrared Sounder （AIRS） can provide the profile information on atmospheric temperature and humidity in high vertical resolution. The assimilation of its radiances has been proven to improve the Numerical Weather Prediction （NWP） in global models. In this study, regional assimilation of AIRS radiances was carried out in a community assimilation system, using Gridpoint Statistical Interpolation （GSI） coupled with the Weather Research and Forecasting （WRY） model. The AIRS channel selection, quality control, and radiances bias correction were examined and illustrated for optimized assimilation. The bias correction scheme in the regional model showed that corrections on most of the channels produce satisfactory results except for several land surface channels. The assimilation and forecast experiments were carried out for three typhoon cases （Saola, Damrey, and Haikui in 2012） with and without including AIRS radiances. Results show that the assimilation of AIRS radiances into the WRF/GSI model improves both the typhoon track and intensity in a 72-hour forecast.

MoSST−DAS:The First Generation Geomagnetic DataAssimilation Framework

Constraining numerical geodynamo models with surface geomagnetic observationsis very important in many respects:it directly helps to improve numericalgeodynamo models,and expands their geophysical applications beyond geomagnetism.A successful approach to integrate observations with numerical models isdata assimilation,in which Bayesian algorithms are used to combine observationaldata with model outputs,so that the modified solutions can then be used as initialconditions for forecasts of future physical states.In this paper,we present the firstgeomagnetic data assimilation framework,which comprises the MoSST core dynamicsmodel,a newly developed data assimilation component(based on ensemble covarianceestimation and optimal interpolation),and geomagnetic field models basedon paleo,archeo,historical and modern geomagnetic data.The overall architecture,mathematical formulation,numerical algorithms and computational techniques of theframework are discussed.Initial results with 100-year geomagnetic data assimilationand with synthetic data assimilation are presented to demonstrate the operation of thesystem.

Skill-assessments of statistical and Ensemble Kalman Filter data assimilative analyses using surface and deep observations in the Gulf of Mexico

A new data assimilation algorithm （Quasi- EnKF） in ocean modeling, based on the Ensemble Kalman Filter scheme, is proposed in this paper. This algorithm assimilates not only surface measurements （sea surface height）, but also deep （-2000 m） temperature observations from the Gulf of Mexico into regional ocean models. With the use of the Princeton Ocean Model （POM）, integrated for approximately two years by assimilating both surface and deep observations, this new algorithm was compared to an existing assimilation algorithm （Mellor-Ezer Scheme） at different resolutions. The results show that, by comparing the observations, the new algorithm out-performs the existing one.