A“Three-index”Seismic Performance Evaluation Method Based on Sino-US Seismic Code

The Code for Seismic Design of Buildings(GB50011-2010)in 2016 and the method of seismic performance-based design for high-rise buildings in the Guide for Performance-based Design of High-Rise Buildings(TBI2017)are compared.In view of the characteristics and limitations of the seismic performance index set by the Sino-US seismic code,a“three-index”performance index system and evaluation process considering the displacement angle of the structural interlayer,the plastic damage degree of components and the plastic strain of material is put forward;combining the example of time-history analysis of a out-of-code high-rise building under the rare earthquakes is verified.The results show that the method of seismic performance evaluation by using deformation control index in Sino-US seismic code is relatively simple;however,both are lacking in the setting of specific components and the whole structure level respectively.The"three-index"system can comprehensively and quantitatively evaluate the seismic performance of out-of-code high-rise buildings.

Evaluating the lifetime performance index with the inverted exponentiated Rayleigh distribution based on censored sample

Lifetime performance index is a powerful and effective way to analyze whether a product achieves the specified standards.In this paper,we investigate the lifetime performance index for the inverted exponential Rayleigh distribution using progressive type II censored sample data.The censored sample is able to greatly save the cost of the experiment and speed up the experiment.We derive the estimation value of lifetime performance index using the maximum likelihood method,and conduct the hypothesis test.Based on extensive numerical simulation,the power function is utilized to assess effectiveness of hypothesis testing.The simulation results show that lifetime performance index is good for determining whether the lifetime of the product reaches the criterion.Finally,a practical dataset is provided to give a demonstration for the procedures of lifetime performance evaluation.

Assessing the lifetime performance index of weighted Lomax distribution based on progressive type-Ⅱ censoring scheme for bladder cancer

In this paper,Health-related quality of life has not been adequately measured in bladder cancer.A recently developed reliable and disease-specific quality of life instrument(Bladder Cancer Index,RCI)was used to measure.Progressive type Ⅱ censoring schemes have potential usefulness in practice where budget constraints in place or there is a necessity for the speedy test.To test the process capability,the lifetime performance index Cl is widely recommended for evaluating the performance of the producfs lifetime and evaluating the lifetime performance index GL for the three-parameter Weighted-Lomax distribution(WLx)under progressive type-II censoring sample for a lower specification limit(L).The statistical inference concerning CL is conducted via obtaining the maximum likelihood of Cl on the base of progressive type-II censoring.The asymptotic normal distribution of the MLE of CL and the confidence interval is proposed.Moreover,the hypothesis testing of CL for evaluating the lifetime performance of WLx data is conducted.Also,assuming the conjugate prior distribution and squared error loss function,this study constructs a Bayes estimator of CL.The Bayes estimator of CL is then utilized to develop a credible interval in the condition of known L.Moreover,we propose a Bayesian test to assess the lifetime performance of products.We also propose a Bayesian test to assess the lifetime performance of products.Finally,two examples are given,one of them is considering a real life data of the remission times of bladder cancer patients in endurance lifetime test and the other is a simulated example to illustrate the usage of the proposed procedure.

Extreme gradient boosting algorithm based urban daily traffic index prediction model:a case study of Beijing,China

The exhaust emissions and frequent traffic incidents caused by traffic congestion have affected the operation and development of urban transport systems.Monitoring and accurately forecasting urban traffic operation is a critical task to formulate pertinent strategies to alleviate traffic congestion.Compared with traditional short-time traffic prediction,this study proposes a machine learning algorithm-based traffic forecasting model for daily-level peak hour traffic operation status prediction by using abundant historical data of urban traffic performance index(TPI).The study also constructed a multi-dimensional influencing factor set to further investigate the relationship between different factors on the quality of road network operation,including day of week,time period,public holiday,car usage restriction policy,special events,etc.Based on long-term historical TPI data,this research proposed a daily dimensional road network TPI prediction model by using an extreme gradient boosting algorithm(XGBoost).The model validation results show that the model prediction accuracy can reach higher than 90%.Compared with other prediction models,including Bayesian Ridge,Linear Regression,ElatsicNet,SVR,the XGBoost model has a better performance,and proves its superiority in large high-dimensional data sets.The daily dimensional prediction model proposed in this paper has an important application value for predicting traffic status and improving the operation quality of urban road networks.

Measuring the social performance of forest management

Forests produce several types of benefits to both forest landowners and society.The social benefit of private forestry is equal to private benefit plus positive externalities minus negative externalities.This study developed alternative metrics for the evaluation of the social benefit of forest management.Forest management was assessed in terms of five criteria:economic,socio-cultural,environmental and ecological performance and the resilience of the forest ecosystem.Each criterion was described with three numerical indicators.Alternative performance indices were calculated from the indicator values using methods developed for multi-criteria decision making.It was concluded that indices based on the multiplicative Cobb-Douglas utility function might be the most recommendable when forestry should produce a balanced combination of different ecosystem services.When the indices were used to compare alternative silvicultural systems in terms of their social performance,continuous cover management was ranked better than even-aged management.The performance of even-aged management improved when it aimed at increasing the share of mixed stands and broadleaf species.Maximizing net present value(NPV) with a 1 % discount rate led to better social performance than maximizing NPV with a 4% discount rate.

Dynamic Analysis and Dimensional Synthesis of Easy-to-Protect Large-Load Robot for Extracting Fermented Grains

To improve the operation situation of difficulty and low efficiency in the extraction of fermented grains(FG),a high-load and large-workspace reclaiming robot for ceramic cylinder fermentation is designed,and a reclaiming effector is designed according to the operating characteristics.Firstly,the kinematics and singularity of the mechanism are analyzed.A multi-domain polar coordinate search method is proposed to obtain the workspace and the volume of the mechanism.Secondly,the dynamic modeling is completed and the example simulation is carried out.Thirdly,the motion-force transmission index of the mechanism is established.And based on the global transmissibility and the good-transmission workspace,the dimensional synthesis of the driving mechanism is completed by using the performance atlas-based method.Finally,aiming at the regular workspace size,stiffness and loading capacity,the Pareto optimal solution set of the executive mechanism dimension is obtained by using the multi-objective particle swarm optimization(MOPSO)algorithm.This paper can provide a theoretical basis for the optimal design and control of FG reclaiming robot.

Fuzzy Based Intelligent Monitoring of Critical Lines in the Restructured Power Market

Restructured electric market environment allows the power wheeling transactions between the power producers and customers to meet the growing load demand. This will lead to the possible of congestion in the transmission lines. The possible contingencies of power components further worsen the scenario. This paper describes the methodology for the identification of critical transmission line by computing the real power and reactive power performance indices. It also demonstrates the importance of fuzzy logic technique used to rank the transmission lines according to the severity and demonstrated on IEEE-30 bus system.

A novel stable value iteration-based approximate dynamic programming algorithm for discrete-time nonlinear systems

The convergence and stability of a value-iteration-based adaptive dynamic programming(ADP) algorithm are considered for discrete-time nonlinear systems accompanied by a discounted quadric performance index. More importantly than sufficing to achieve a good approximate structure, the iterative feedback control law must guarantee the closed-loop stability. Specifically, it is firstly proved that the iterative value function sequence will precisely converge to the optimum.Secondly, the necessary and sufficient condition of the optimal value function serving as a Lyapunov function is investigated. We prove that for the case of infinite horizon, there exists a finite horizon length of which the iterative feedback control law will provide stability, and this increases the practicability of the proposed value iteration algorithm. Neural networks(NNs) are employed to approximate the value functions and the optimal feedback control laws, and the approach allows the implementation of the algorithm without knowing the internal dynamics of the system. Finally, a simulation example is employed to demonstrate the effectiveness of the developed optimal control method.

Hydrological Modeling: A Better Alternative to Empirical Methods for Monthly Flow Estimation in Ungauged Basins

Water resource is required for agricultural, industrial, and domestic activities and for environmental preservation. However, with the increase in population and growth of urbanization, industrialization, and commercial activities, planning and management of water resources have become a challenging task to meet various water demands globally. Information and data on streamflow hydrology are, thus, crucial for this purpose. However, availability of measured flow data in many cases is either inadequate or not available at all. When there is no gauging station available at the site of interest, various empirical methods are generally used to estimate the flow there and the best estimation is chosen. This study is focused on the estimation of monthly average flows by such methods popular in Nepal and assessment of how they compare with the results of hydrological simulation. Performance evaluation of those methods was made with a newly introduced index, Global Performance Index (GPI) utilizing six commonly used goodness-of-fit parameters viz. coefficient of determination, mean absolute error, root mean square error, percentage of volume bias, Nash Sutcliff Efficiency and Kling-Gupta Efficiency. This study showed that hydrological modeling is the best among the considered methods of flow estimation for ungauged catchments.

Classification of inelastic deformation and material-intrinsic indices about mechanical performance of general solid matter

The present article is aimed to detect material-intrinsic indices that can be used to supervise the mechanical performance of general solid matter.The novelty carried in this article can be summarised as follows.Firstly,an inelastic deformation state of almost any solid matter can be treated as the combination of two fundamental modes due to different microscopic causation:Mode I inelastic distortion due to the movement of sliding types of defects and Mode II inelastic dilation due to the evolution of voids/bubbles.Secondly,each inelastic deformation mode is characterised by a single principal inelastic deformation descriptor(PIDD):Mode I by a newly introduced quantity of maximum distortional angle changeαand Mode II by the logarithm of dilating magnificationω.In particular,the concept of maximum distortional angle change gives rise to a geometrically intuitive yield criterion ofα>α_(c),which in situations of small deformation,is shown to asymptote von Mise's,and to become Tresca's in cases of plane stress.Thirdly,the deformation process of a solid matter under monotonic and ambient loads is formulated by means of trajectories of thermodynamic equilibria with respect to the PIDD pair.Then a pair of physical quantities which measure the stresses needed to change the local PIDD state are singled out.Being termed as inelastic deformation resistances(IDRs),these two quantities are shown to depend only on the onsite atomic configurations.It is also shown that key descriptive properties about the mechanical behaviours of materials,such as ductility,are encoded in IDRs as functions of PIDDs.Hence the IDR pair may serve as material performance indices that may be more intrinsic than conventional stress-strain relationships.

An Optimal Control Theory Based Analysis of Brushless DC Motor Drive

The application of BLDC motor drives in industries is becoming more popular nowadays. An error will occur in the drive that is originated by some disturbances which are the major problems to reduce the stability of the system. To obtain the minimum performance index, the optimal control signal is formulated, which is the main objective of this paper. Based on quadratic performance index, the optimal control system of BLDC motor drive is a design which spotlights in this paper. The complexity of the mathematical expressions has been reduced by using state space approach to the BLDC system. The burden to the control engineers has reduced based on tedious computation by using thus optimal design. To provide the desired operating performance, this optimal design helps to realize the BLDC system with practical components.

Study on the evaluation method of diffuse radiation models——taking 5 typical cities in China as examples

Diffuse solar radiation models play an extremely important role in solar photothermal utilization,resource assess-ment and energy consumption simulation,etc.The accuracy of these diffuse solar radiation models usually need to be evaluated by various statistical parameters.Among these statistical parameters,the Global Performance In-dex(GPI)has been extensively employed in recent years because of its comprehensiveness and wide applicability.This paper takes five cities in China as representatives of 5 typical climate regions,and 12 solar scattered radia-tion models are fitted with the meteorological data of 5 cities.Based on the comparative analysis of the existing GPI calculation methods,this paper points out that there are some defects in the existing GPI,and modifies the existing GPI based on the comprehensive consideration of statistical parameters,normalization preprocessing of statistical parameters,unified evaluation direction of parameters,weight redistribution of statistical parameters,and adjustment of extreme coefficient.12 types of new GPI are established in this paper,and the performance of diffuse solar radiation models are compared based on these GPI.The rationality of GPI corrective measures is analyzed by means of the method reasonable index(MRI).The results show that the GPI calculation method(N10)which takes five corrective measures has the best performance,and the accuracy of the existing GPI can be improved by 13.33 to 65%.

KPI-based Real-time Situational Awareness for Power Systems with a High Proportion of Renewable Energy Sources

With the increasing complexity of power systems and the widespread penetration of renewable energy sources(RES),real-time situational awareness for power systems is of great significance for operational scheduling.Considering the impact of RES on power system operations,a situational awareness key performance index(KPI)system for power systems with a high proportion of RES is proposed in this paper,which consists of reserve capacity abundance,ramp resource abundance,center of inertia(COI)frequency deviation,interface power flow margin,synthesized voltage stability,and angle stability margin.Then,the KPIs are synthesized and visualized by the decision tree method and radar chart method,respectively,for monitoring the operation states(i.e,normal,alert,and emergency states)of power systems with a high proportion of RES.Numerical simulations are conducted in a revised New England 16-machine 68-bus power system and an actual CEPRI-RE power system in the northwest region of China with a high proportion of RES.The results show that the proposed KPI-based situational awareness method is able to accurately monitor the real-time state of power systems with a high proportion of RES,and can assist power dispatchers to make effective decisions.

Material selection combined with optimal structural design for mechanical parts

To reduce the environmental impact of mechanical parts, an approach integrating structural design and material selection was studied. Adding the discrete variable of material, a hybrid optimization model was built with the aim of minimizing environmental impact and based on an ordinary structure optimization model. An optional material set was built by combining measures of qualitative and quantitative screening, while the lifecycle environmental impact of the materials was quantified using the method of Eco-indicator 99. Two groups of structurally optimal solutions were calculated with ideal and negative-ideal materials selected respectively, and then the hybrid model was simplified by comparing the solutions. A material environmental performance index was calculated using an analytic method. By comparing this index for every material in the optional material set, the optimal material can be found and the structural solutions calculated. This method was applied to a dowel bar design process as a case study. The results show that the environmental impact of each material has a significant effect on the optimal structural solution, and it is necessary to study the integration of structural design and material selection.

Study on Organic Wood-flour Putty

This work was undertaken to research organic wood-flour putty as wooden surface undercoat. Four types of wood-flour (300, 500, 800 and 1 000 mesh) were prepared through the technological processes of shattering, coarse grinding and fine grinding. And latex (16% of solid content) and two kinds of agents (A and B) were added into the putty. In this experiment, effects of agent and particle size of wood-flour on properties of organic wood-flour putty, such as painting properties, water resistance, and abrasive resistance and so on, were discussed. The results showed that considering all of performance indexes, wood-flour putty contained with 8.0% agent A or 2.0% agent B has a better performance than the others. In addition, wood-flour putty with 500 mesh of wood-flour is the best.

Advances in research of intracranial vascular stent

In recent years, China's population has shown an obvious aging trend. This trend has been accompanied by an increased incidence of cardiovascular disease and death.Intracranial stenting has become an important treatment modality for intracranial vascular disease because it is effective, safe, and widely approved. In this paper,we review the literature concerning the classification, structure, preparation, and performance of intracranial stents. We also summarize problems and future prospects in the context of intracranial stents. This paper will serve as a reference for the future research and development of intracranial stents.