Health diagnosis of ultrahigh arch dam performance using heterogeneous spatial panel vector model

Currently,more than ten ultrahigh arch dams have been constructed or are being constructed in China.Safety control is essential to long-term operation of these dams.This study employed the flexibility coefficient and plastic complementary energy norm to assess the structural safety of arch dams.A comprehensive analysis was conducted,focusing on differences among conventional methods in characterizing the structural behavior of the Xiaowan arch dam in China.Subsequently,the spatiotemporal characteristics of the measured performance of the Xiaowan dam were explored,including periodicity,convergence,and time-effect characteristics.These findings revealed the governing mechanism of main factors.Furthermore,a heterogeneous spatial panel vector model was developed,considering both common factors and specific factors affecting the safety and performance of arch dams.This model aims to comprehensively illustrate spatial heterogeneity between the entire structure and local regions,introducing a specific effect quantity to characterize local deformation differences.Ultimately,the proposed model was applied to the Xiaowan arch dam,accurately quantifying the spatiotemporal heterogeneity of dam performance.Additionally,the spatiotemporal distri-bution characteristics of environmental load effects on different parts of the dam were reasonably interpreted.Validation of the model prediction enhances its credibility,leading to the formulation of health diagnosis criteria for future long-term operation of the Xiaowan dam.The findings not only enhance the predictive ability and timely control of ultrahigh arch dams'performance but also provide a crucial basis for assessing the effectiveness of engineering treatment measures.

Evaluating Contractors’ Safety Record and Its Influence on Performance of Road Infrastructural Projects

A number of studies conducted in Kenya and internationally indicated that most of the construction firms and contractors do not seem to strictly observe safety administration in construction industry, hence compromised performance at implementation stage of projects and even later in the post implementation or post-delivery stage. The study aimed to examine the influence of contractors’ safety record on road performance. This is to create better understanding of how the safety record of contractors could either positively or negatively influence performance of roads during post-delivery stage. The study used both descriptive survey research design and correlation design based on a pragmatic mixed method approach. Through stratified sampling and proportionate sampling, a sample of 210 was drawn from a population of 460 comprising of registered contractors and Public Service Vehicles (PSV) drivers within Nairobi County in Kenya. Questionnaires were distributed using simple random sampling. The questionnaires returned were 153 in total representing 72.8% of all questionnaires distributed to the respondents. Data was descriptively analyzed using percentages, frequencies, means and standard deviations for measuring central tendency and variability. Inferential analysis was done by use of correlation and regression. The descriptive analysis revealed that safety policy management system, insurance policy, and adequacy of standards in addressing safety outcome are to some extent practiced and adhered to. However, compliance behavior to safety procedures is still weak and requires improvement. The null hypothesis was tested and the results obtained from a simple linear regression indicated that, R = 0.657, R2 = 0.431, B = 0.359, t = 10.703, F (1,151) = 114.558, p = 0.000 < 0.05. This means that contractors’ safety record has a strong positive and significant relationship with road performance and that 43.1% of variation in performance is explained by safety record. This study recommends that contractors’ safety record should be part, and parcel of the evaluation criteria used in selection of a suitable road contractor to ensure road performance is achieved even after construction is completed. The study is significant in that it contributes to the body of knowledge by providing empirical data on the need for safety procedures in urban road construction and beyond.

Influence of heat treatment on microstructure,mechanical and corrosion behavior of WE43 alloy fabricated by laser-beam powder bed fusion

Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.However,the as-built part usually exhibits undesirable microstructure and unsatisfactory performance.In this work,WE43 parts were firstly fabricated by PBF-LB and then subjected to heat treatment.Although a high densification rate of 99.91%was achieved using suitable processes,the as-built parts exhibited anisotropic and layeredmicrostructure with heterogeneously precipitated Nd-rich intermetallic.After heat treatment,fine and nano-scaled Mg24Y5particles were precipitated.Meanwhile,theα-Mg grainsunderwent recrystallization and turned coarsened slightly,which effectively weakened thetexture intensity and reduced the anisotropy.As a consequence,the yield strength and ultimate tensile strength were significantly improved to(250.2±3.5)MPa and(312±3.7)MPa,respectively,while the elongation was still maintained at a high level of 15.2%.Furthermore,the homogenized microstructure reduced the tendency of localized corrosion and favoredthe development of uniform passivation film.Thus,the degradation rate of WE43 parts was decreased by an order of magnitude.Besides,in-vitro cell experiments proved their favorable biocompatibility.

Jet Behavior and Metallurgical Performance of Innovated Double-Parameter Oxygen Lance in BOF

A double-parameter oxygen lance used in a 300 t converter was designed to improve the metallurgical performance. A small-scale measurement of the jet behavior was done using a computer controlled scanning system. The experimental data on the velocity distribution at the jet centerline, the contour map of the jet velocity, the deviation of the jet centerline, and the velocity distribution of the axial section were compiled. According to the results of the small-scale measurement, the double-parameter lance was also employed for a BOF experiment. The metallurgy inde- xes show that the metallurgical performance was highly promoted by use of the double-parameter lance.

Creep aging behavior and performance of Al-Zn-Mg-Cu alloys under different parameters in retrogression aging treatment

A study was conducted to better understand how different parameters, namely, regression aging time and regression aging temperature, affect the creep aging properties, i.e., the creep deformation and performance of Al-Zn-MgCu alloy during regressive reaging. The corresponding creep strain and mechanical properties of samples were studied by conducting creep tests and uniaxial tensile tests. The electrical conductivity was measured using an eddy-current conductivity meter. The microstructures were observed by transmission electron microscopy(TEM). With the increase in regression aging time, the steady creep strain first increased and then decreased, and reached the maximum at 45 min.The steady creep strain increased with the increase in regression aging temperature, and reached the maximum at 200 ℃.The level of steady creep strain was determined by precipitation and dislocation recovery. Creep aging strengthens 7B50-RRA treated with regression aging time at 190 ℃ for 10 min, and the difference in the mechanical properties of alloy becomes smaller. The diffusion of solute atoms reduces the scattering of electrons, leading to a significant improvement in electrical conductivity and stress corrosion cracking(SCC) resistance after creep aging. The findings of this study could help in the application of creep aging forming(CAF) technology in Al-Zn-Mg-Cu alloy under RRA treatment.

Effects of Reduced Nocturnal Temperature on Performance and Behavior of Nursery Pigs

Previous studies suggested that pigs prefer lower environmental temperatures during nighttime compared to daytime. So reducing nocturnal temperature in nursery barns may not jeopardize performance or welfare of pigs, but can save energy for heating the barn. A study was conducted to investigate growth performance and behavioral response of nursery pigs to reduced nocturnal temperature. This study was conducted in four replicates, each utilizing 270 newly weaned pigs and lasting for 5 wk. Temperature setpoint in the control room （CON） was started at 30℃ and decreased by 2℃ per week. In the treatment room （RNT）, temperature setpoint was maintained same as in CON between 7：00 h and 19：00 h, and reduced by 8~C between 19：00 h and 7：00 h starting from d 5. Growth performance （15 pens/room, 9 pigs/pen, BW=（6.3±0.61） kg） was monitored for 5 wk, and behaviors in 6 pens in each room were video-recorded for 24 h 3 d after being exposed to the experimental temperature. Instantaneous scan sampling was performed to determine time budgets for standing, sitting, eating, drinking, belly nosing, three postures of lying, and huddling. Two focal pigs were continuously viewed to record duration and occurrence of eating and drinking. Reduced nocturnal temperature did not affect the growth performance of the pigs, time spent standing, sitting, total lying and eating or duration and frequencies of eating and drinking （all P〉0.10）. However, RNT increased time spent lying sternal （83 vs. 72%, P〈0.001） and number of pigs that were huddling （70 vs. 50% of lying pigs, P〈0.001）, and decreased time spent lying laterally （0.8 vs. 4.6%, P〈0.001）, lying half laterally （5.3 vs. 11.0%, P〈0.001）, and belly nosing （0.9 vs. 1.7%, P=0.01） during nighttime. These results indicate that nursery pigs adopted the posture of lying sternal and huddled together to reduce heat loss from their body surface to maintain thermal balance and growth performance in RNT. Such mild reduction in nocturnal temperature in the nursery barn can save energy for heating the barn without negative effects on performance and behavior of nursery pigs.

Effects of different feeding methods and space allowance on the growth performance, individual and social behaviors of Holstein calves

The importance of nutrient provisions and weaning methods for calves has been well established over the past few years,while as increasing interest has focused on contribution of animal behavior and their overall performance in production regimes.The present study investigated the effects of feeding methods and space allowance on growth performance,individual and social behaviors in Holstein calves.Twenty-four Chinese Holstein male and female calves were allocated to either an individual or group of 6 and fed either with a bucket or a teat.Milk replacer,calf starter,and Chinese wildrye were offered during the experiment.A fecal index used in the present study was defined as the total fecal scores/total number of calves in each treatment.The results showed that there was no significant difference among the 4 treatments in terms of feed intake,body weight,average daily gain,and fecal index.For the feeding behaviors,the ingesting milk time and ingesting milk rate were significantly affected by space allowance,while the feeding methods showed a significant influence on the bunting behavior of the calves.There was no significant difference among the 4 treatments in terms of licking fixtures,self-grooming,and lying down behaviors,irrespective of the feeding method or space allowance.However,sucking an empty bucket or the teat was significantly affected by the feeding method.Several selected group behaviors were examined in the present study,and similar values for sniffing the other calves,social grooming,and cross-sucking behaviors were observed.Overall,the present study demonstrated that different feeding methods and space allowances had a significant effect on the feeding behavior of calves,while the feed intake,growth performance,health condition,individual and group social behaviors were not significantly influenced.Furthermore,under intensified production systems,Holstein calves raised in a group may obtain a similar production performance,thus reducing management input and profitability compared with those kept individually.However,there may be competition during the feeding period.

Effect of yttrium and calcium additions on electrochemical behaviors and discharge performance of AZ80 anodes for Mg-air battery

The effects of yttrium(Y)and yttrium+calcium(Y+Ca)additions on the electrochemical properties and discharge performance of the as-extruded Mg−8Al−0.5Zn−0.2Mn(AZ80)anodes for Mg−air batteries were investigated.The results show that the addition of 0.2 wt.%Y increased the corrosion resistance and discharge activity of AZ80 anode.This was attributed to the fine and sphericalβ-Mg_17)Al_(12) phases dispersing evenly in AZ80+0.2Y alloy,which suppressed the localized corrosion and severe“chunk effect”,and facilitated the rapid activation ofα-Mg.Combinative addition of 0.2 wt.%Y and 0.15 wt.%Ca generated grain refinement and a reduction of theβ-Mg_17)Al_(12) phase,resulting in a further enhancement in discharge voltage.However,the incorporation of Ca in Mg_17)Al_(12) and Al_(2)Y compounds compromised the corrosion resistance and anodic efficiency of AZ80+0.2Y+0.15Ca anode.Consequently,AZ80+0.2Y anode exhibited excellent overall discharge performance,with the peak discharge capacity and anodic efficiency of 1525 mA·h·g^(−1) and 67%at 80 mA/cm^(2),13%and 14%higher than those of AZ80 anode,respectively.

Influence of bismuth on microstructure,thermal properties,mechanical performance,and interfacial behavior of SAC305−xBiCu solder joints

This research sought to improve the properties of SAC305 solder joints by the addition of 1 and 2 wt.%Bi.The effects of bismuth doping on the microstructure,thermal properties,and mechanical performance of the SAC305−xBiCu solder joints were investigated.Bi-doping modified the microstructure of the solder joints by refining the primaryβ-Sn and eutectic phases.Bi-doping below 2 wt.%dissolved in theβ-Sn matrix and formed a solid solution,whereas Bi additions equal to or greater than 2 wt.%formed Bi precipitates in theβ-Sn matrix.Solid solution strengthening and precipitation strengthening mechanisms in theβ-Sn matrix increased the ultimate tensile strength and microhardness of the alloy from 35.7 MPa and 12.6 HV to 55.3 MPa and 20.8 HV,respectively,but elongation decreased from 24.6%to 16.1%.The fracture surface of a solder joint containing 2 wt.%Bi was typical of a brittle failure rather than a ductile failure.The interfacial layer of all solder joints comprised two parallel IMC layers:a layer of Cu6Sn5 and a layer of Cu3Sn.The interfacial layer was thinner and the shear strength was greater in SAC305−xBiCu joints than in SAC305Cu solder joints.Therefore,small addition of Bi refined microstructure,reduced melting temperature and improved the mechanical performance of SAC305Cu solder joints.

Contractor Monitoring and Performance of Road Infrastructure Projects in Uganda: A Management Model

An understanding of the influence of contractor monitoring on performance of road infrastructural projects in Uganda provided an impetus for this study. The objectives of the study were to: assess the relationship between contractors monitoring and performance of national road infrastructure projects and the relationship between contractor monitoring components and performance of national road infrastructure projects in Uganda. Purposive sampling was employed in selecting the procurement professionals, engineers and simple random sampling was adopted in selecting private consultants, members of parliament and respondents from the civil society organizations. Data for this study were collected using a closed ended questionnaire and interviews. Some of the major finding from this study include: weak procurement rules which lead to awarding road projects to incompetent contractors;contractor monitoring being handled by unqualified, incompetent and inexperienced professionals;lack of contractors and contract supervisors appraisal system;delay of contractors payments which affects timelines in services delivery;lack of a strong internal project monitoring and evaluation mechanism at the Uganda National Roads Agency (UNRA). The research therefore recommends the establishment of an Independent Public Infrastructure Development and Monitoring Unit by government and adoption of systems that appraise both contractors and contract supervisors with clear disciplinary actions for unsatisfactory performance by the UNRA.

Container Networking Performance Analysis for Large-Scale User Behavior Simulation

Accurately simulating large-scale user behavior is important to improve the similarity between the cyber range and the real network environment. The Linux Container provides a method to simulate the behavior of large-scale users under the constraints of limited physical resources. In a container-based virtualization environment, container networking is an important component. To evaluate the impact of different networking methods between the containers on the simulation performance, the typical container networking methods such as none, bridge, macvlan were analyzed, and the performance of different networking methods was evaluated according to the throughput and latency metrics. The experiments show that under the same physical resource constraints, the macvlan networking method has the best network performance, while the bridge method has the worst performance. This result provides a reference for selecting the appropriate networking method in the user behavior simulation process.

Dynamic Compression Behavior of Ultra-high Performance Cement-based Composite with Hybrid Steel Fiber Reinforcements

Ultra-high performance cement-based composites (UHPCC) is promising in construction of concrete structures that suffer impact and explosive loads.In this study,a reference UHPCC mixture with no fiber reinforcement and four mixtures with a single type of fiber reinforcement or hybrid fiber reinforcements of straight smooth and end hook type of steel fibers were prepared.Split Hopkinson pressure bar (SHPB) was performed to investigate the dynamic compression behavior of UHPCC and X-CT test and 3D reconstruction technology were used to indicate the failure process of UHPCC under impact loading.Results show that UHPCC with 1% straight smooth fiber and 2% end hook fiber reinforcements demonstrated the best static and dynamic mechanical properties.When the hybrid steel fiber reinforcements are added in the concrete,it may need more impact energy to break the matrix and to pull out the fiber reinforcements,thus,the mixture with hybrid steel fiber reinforcements demonstrates excellent dynamic compressive performance.

Neuroscience for Architecture:How Building Design Can Influence Behaviors and Performance

The purpose of this paper is to discuss recent findings in neuroscience that can be useful to architecture.Knowing the working patterns of the brain and how space affects cerebral functions can help architects design buildings that improve the user’s behavior,performance and well-being.The built environment has a direct impact on the human brain.Social relations,focus,cognition,creativity,memory and well-being can be influenced by the surrounding physical space.Although it is not possible to create the perfect room,the space can be used in a strategic way,depending on the task that individuals are supposed to do there and depending on the people(age,gender,culture)who will make use of the space.Schools can be designed in a way to improve cognition,learning and memorization;hospital buildings can help improving recovery;workspaces can improve performance,creativity and collaboration.Above all,all spaces of long occupation should be designed in a way to improve well-being.How can architecture change automatic behaviors and nudge people to behave in a healthier way?Can architects create buildings and cities that improve socialization and happiness?Can criminality levels drop due to changes on the way the environments are designed?These are some of the questions that will be discussed in this paper.

Effects of Drinking Slightly Acidic Electrolytic Water on Growth Performance and Behavior of Broilers

[Objective]The paper was to study the effects of drinking slightly acidic electrolytic water on growth performance and behavior of Rose 308 broilers,and to provide reference for the application of slightly acidic electrolytic water in broiler breeding.[Method]A total of 300 healthy 10-day-old Rose 308 broilers with similar body weight were randomly divided into five groups,three replicates each group,20 broilers each replicate.The broilers in control group were supplied with normal drinking water,and the broilers in experimental groups consumed slightly acidic electrolytic water with 0.3,0.5,0.7,1.0 mg/L residual chlorine,respectively.The test lasted 21 d.[Result]At 10-30 days of age,the water consumption of broilers in 0.7 and 1.0 mg/L electrolytic water groups were increased by 9.27%and 7.67%respectively compared with the control group(M<0.05).The average daily feed intake(ADFI)of broilers in 0.7 and 1.0 mg/L electrolytic water groups were increased compared with the control group(Q0.05).The average daily gain(ADG)of broilers in 0.7 mg/L electrolytic water group was 11.99%lower than that in control group(M<0.05).The feed gain ratio(F/G)of broilers in 0.5 mg/L electrolytic water group was 12.29%lower than that in control group(M<0.05),and the mortality was the lowest in 0.5 mg/L electrolytic water group.The standing,feeding and drinking frequency of broilers in experimental groups were higher than that in control group,and the flapping behavior of broilers in 0.5 mg/L electrolytic water group was the lowest.[Conclusion]Drinking slightly acidic electrolytic water has positive effect on the growth and behavior of broilers.

Effect of ZrO_2 Dopant on the Sintering Behavior and Performance of MCMB-derived Carbon Laminations

Liquid ball-milling dispersant method was used to prepare the ZrO2-doped carbon laminations from mesocarbon microbeads（MCMBs）. After sintering at 1 300 ℃ in nitrogen atmosphere, the effect of ZrO2 concentration on sintering behavior, electric conductivity as well as bending strength of the carbon laminations was investigated in detail. The results showed that the volumetric shrinkage rate of the carbon laminations decreased from 38.2% to 30.9% when the ZrO2 concentration in raw materials varied from 0 to 16 wt%. Compared with undoped carbon lamination, the samples had high-electric conductivity and excellent bending strength in all cases. The electric conductivity achieved the maximum value of 225 S/cm, and the bending strength of the carbon lamination was 119.24 MPa for a concentration of 8 wt% ZrO2 in raw materials. In addition, the electric conductivity and bending strength reducing were observed when the ZrO2 concentration was higher than 8 wt%. The catalytic effect on graphitization for the carbon laminations was the most effective when the ZrO2 concentration was set at 8 wt% in raw materials.

Synthetic Evaluation of Contractor's Performance in Outcome-Based Contract

Outcome-based contract( OBC) is a kind of contracting mechanism,which allows the customer to pay only when the firm has delivered outcomes,rather than activities and tasks involved. To achieve the higher demand of the delivering outcome of the contract,the evaluation of contractor's performance was focused on. A reasonable and objective contractor performance evaluation system is constructed by considering various uncertainties. The set pair theory is used to analyze the four-element connection of quality of service contractors. It aims to provide a theoretical basis for the decisionmaker to make confirmation of the equipment contractor who has a better performance and development trend.

Influence of Reading Behavior of Entrepreneurs on Their Entrepreneurial Performance: Empirical Study of Chongqing

In the context of economic downward and industrial structural adjustment,cultural level of entrepreneurs exerts direct influence on entrepreneurial results,while reading behavior of entrepreneurs is closed connected with cultural level of entrepreneurs. Therefore,it is of utmost importance to analyze the relation between reading behavior and entrepreneurial performance. Based on the survey data of 200 enterprises in one- hour economic circle of Chongqing,this paper analyzed three dimensions of reading behavior of entrepreneurs: reading subjects,reading media,and reading environment. It analyzed the relation between these three indicators and entrepreneurial performance. It further divided entrepreneurial performance into survival performance and financial performance. Finally,it came up with following conclusions:( i) good reading exerts significantly positive effect on survival performance of entrepreneurial enterprises;( ii) suitable reading environment plays a positive role in financial performance of entrepreneurial enterprises.

Effects of Different Feeding Methods on Behaviors, Immunities and Growth Performances of Suckling Calves

Behaviors,immunities and growth performances of suckling calves to either fed milk through barrel feeding or artificial nipple feeding were investigated in this study.Seventy-two newborn female suckling Holstein calves were selected and divided into two treatments which fed regular milk through milk barrels or artificial nipples.The behaviors′parameters were measured on 14,29 and 44 days.Body weight and body size of the calves were recorded on 15,30 and 45 days.Immune indicators were collected in quiet situation on 15,30 and 45 days.Compared with the barrel feeding method,calves fed by artificial nipples had less non-nutritive behaviors,stronger growth performances and higher immune levels.Artificial nipples gave calves sucking conditions and reduced the motivation of calves to suck each other,which might promote the development of complex stomachs,allow food to be better digested and more effective.It also reduced cross-infection indirectly which increased the calves'immunities.

Prediction of Client Support on Contractor Performance as a Critical Success Factor

The aim of this study was to assess the influence of client support on performance of contractors within the road construction industry in Kenya. The study adopted descriptive survey research design and correlation research design. The target population was 156 selected from road contractors, engineers working in road authorities, technical auditors and consultants in the road sector. Stratified and proportionate sampling techniques were employed in coming up with a sample size of 62 respondents drawn from a target population of 156. From the simple linear regression conducted, the findings revealed that client support influences the performance of contractors in the road construction sector. Thus, we recommend that client support is highly needed to avoid issues such as delayed payment that would adversely affect performance of contractors in the road construction industry. This will subsequently lead to timely completion of roads, achieving cost effective and quality road projects.

Ransomware Classification Framework Using the Behavioral Performance Visualization of Execution Objects

A ransomware attack that interrupted the operation of Colonial Pipeline(a large U.S.oil pipeline company),showed that security threats by malware have become serious enough to affect industries and social infrastructure rather than individuals alone.The agents and characteristics of attacks should be identified,and appropriate strategies should be established accordingly in order to respond to such attacks.For this purpose,the first task that must be performed is malware classification.Malware creators are well aware of this and apply various concealment and avoidance techniques,making it difficult to classify malware.This study focuses on new features and classification techniques to overcome these difficulties.We propose a behavioral performance visualization method using utilization patterns of system resources,such as the central processing unit,memory,and input/output,that are commonly used in performance analysis or tuning of programs.We extracted the usage patterns of the system resources for ransomware to performbehavioral performance visualization.The results of the classification performance evaluation using the visualization results indicate an accuracy of at least 98.94%with a 3.69%loss rate.Furthermore,we designed and implemented a framework to perform the entire process—from data extraction to behavioral performance visualization and classification performance measurement—that is expected to contribute to related studies in the future.