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The purpose of this paper is to explore how curved road and lane-changing rates affect the stability of traffic flow.

An extended two-lane lattice hydrodynamic model on a curved road accounting for the empirical lane-changing rate is presented. The linear analysis of the new model is discussed, the stability condition and the neutral stability condition are obtained. Also, the mKdV equation and its solution are proposed through nonlinear analysis, which discusses the stability of the extended model in the unstable region. Furthermore, the results of theoretical analysis are verified by numerical simulation.

The empirical lane-changing rate on a curved road is an important factor, which can alleviate traffic congestion.

This paper does not take into account the factors such as slope, the drivers’ characters and so on in the actual traffic, which will have more or less influence on the stability of traffic flow, so there is still a certain gap with the real traffic environment.

The curved road and empirical lane-changing rate are researched simultaneously in a two-lane lattice hydrodynamic models in this paper. The improved model can better reflect the actual traffic, which can also provide a theoretical reference for the actual traffic governance.

The purpose of this paper is to review the theoretical background, methodological extensions, and empirical applications of the Engel curve, which is applied to the research of the change in farmers’ welfare and food demand in China after the economic reform in 1978, compared with the statistics of income and food consumption.

This paper mainly uses the traditional method of Engel curve, which is compared with income growth and food consumption, to study farmers’ welfare improvement in rural China.

The Engel coefficients identify three different stages for farmers’ welfare change after 1978. The first stage is the period between 1978 and 1988, in which farmers’ welfare has been continuously enhanced due to the institutional bonus of the 1978 economic reform and increased government purchase price of agricultural products. The second stage is the period between 1989 and 1995, in which farmers’ welfare has been slightly deteriorated mainly due to the end of institutional reform bonus, suppressed food prices, relative high inflation, and instable political situation. The third stage is the period after 1995, in which farmers’ welfare returns to a growing path, as the dual price system was abolished, the transition from a planned economy to a market economy had been completed, and the government carried out protective policies for agriculture and started to heavily subsidize agriculture. The Engel coefficient still remained at a very high level at 0.59 in 1995, but it continuously decreased to 0.33 in 2015. The welfare enhancement for farmers mainly results from deepened market-oriented reform, protective policies for agriculture, and prevalent off-farm employment. The Engel coefficient is also linked to food demand elasticities. Along with the decreasing Engel coefficient in the past 40 years, income elasticities also continuously decrease from 0.55 in 1978 to 0.08 in 2015. Food demand is very inelastic now, and any further increase in income will not substantially increase food demand any more.

Inequality has not been analyzed.

This paper reviews the methodological advantages of the Engel curves, and uses it to identify different stages of welfare change and estimate income elasticities of food demand for farmers in China after the 1978 economic reform.

The origin and applications of learning curves. Learning curves were first noticed by aircraft producers before World War II. The time taken to assemble a new type of aircraft diminished with each successive airframe built. Typically, the time taken for assembly had dropped by 20% each time the cumulative output had doubled. Later, similar “start up effects” were noticed in many other industries, and were used for contract negotiations and for cost control. Prices of new products, especially chemicals, often fell with time and output according to some kind of “learning curve”. However exceptions to the “learning curve” were sometimes found. Assembly times sometimes ceased to drop, or dropped at different rates at different sites.

This paper lays out the uses of demand curves, both for profit optimization, strategy, tiering and list price setting. This tool is also useful in public policy, such as extending health‐care coverage. It describes how to build a demand curve, and draw useful conclusions.

This paper provides examples of actual demand curves, and how they have been used for new product development, and in out‐maneuvering competitors. Examples are drawn from a number of industries, such as telecom, information services, insurance and electronics, and show how supply and demand are not static, but are highly interactive.

Companies and legislators are not familiar with the demand curves, despite its long history of use in academia. As a result of unfamiliarity with this tool, companies often make costly mistakes in estimates of new product uptake and volumes. If instead of demand curves they rely on price elasticities, companies deprive their senior management of a tool that suggests strategic responses to competitive situations. Surprisingly, many companies have never actually developed a demand curve for their markets.

This article allows managers have not actually seen a real demand curve to see one, and understand what this tool could do for them. It gives examples of new product development and tiering to address multi‐price level markets. In addition, it suggests how public policy makers should focus on shaping supply and demand, rather than imposing floors or ceilings on prices for health‐care coverage. Price ceilings today are responsible for widespread gaps in health care coverage. Finally, the literature on demand curves fails to show how supply and demand are highly interactive.

In order to determine the range of medium temperature zone of road asphalt, it is hoped that the evolution of viscoelastic characteristics of road asphalt under medium temperature state can be deeply explored.

In this paper, the needle penetration test and temperature scanning test were designed for 90# and 70# bitumen as test materials, and the boundary of medium temperature zone of 90# and 70# bitumen was accurately determined by data analysis method. A mathematical model was established based on principal component analysis, and a comprehensive evaluation index was proposed to evaluate the evolution of temperature viscoelastic characteristics of road asphalt by means of standardization and rotational dimensionality reduction.

The test results show that the medium temperature zone of 90# asphalt is [−5 ± 1°C, 38 ± 1°C], and the medium temperature zone of 70# asphalt is [0 ± 1°C, 51 ± 1°C]. According to the viscoelastic response of road asphalt in the medium temperature zone, the medium temperature zone can be divided into three evolution stages: weak viscoelastic stage, viscoelastic equilibrium stage, strong viscoelastic weak stage. Analysis based on the intrinsic viscosity fillip target describing the various intrinsic viscoelastic index represents the viscoelastic properties of bitumen from different angles, and limitations inherent stick fillip for target put forward the integrated the inherent stick fillip mark information, as well as targeted and accurate evaluation of road asphalt temperature comprehensive evaluation indexes in the evolution of the viscoelastic properties of I_M-T. Finally, the temperature data of asphalt pavement in several representative regions of China are compared with the determined medium temperature region, and it is proved that the research on the evolution of viscoelastic characteristics of asphalt pavement under the medium temperature condition has important practical significance.

The boundary of medium temperature zone of 90# and 70# base asphalt was determined, and the viscoelastic characteristic evolution of road asphalt under medium temperature state was studied deeply. Aiming at the limitation of intrinsic viscoelastic index, a comprehensive evaluation index IM-T which not only integrates the information of intrinsic viscoelastic index but also can accurately evaluate the evolution of temperature viscoelastic characteristics in road asphalt is proposed.

A management summary of the theory and propositions with regard to the engineering of vision and culture in “corporate entities” is provided. It has been based on a book of the same title by the author, published in 1989 by Heinemann in the United Kingdom. In addition, a number of considerations and suggestions have been included in support of further research. The proposed diagnostic management model on organisational and possibly national dynamics emerged in a corporate rather than an “academic” campus. Its particular relevance therefore is both a reflection of an inductive reasoning process on corporate and national events, and of the practitioner′s need to cope with the continuous challenge of structural change.

Episodes of compulsive eating may lead to addiction. Changing relative prices does not always work for many food addicts turned overweight or obese individuals. This paper points to when such situations may arise and how they can be remedied.

We modify the standard neoclassical economics model assumption of indifference curves being convex to the origin. It becomes violated in situations when compulsive eaters become food addicts. As a result of that, the assumption of the concave (quasi-concave) utility function is violated too. We also introduce the possibility that compulsive eaters may have stable but nonconstant preferences.

Most important finding of our model is that a smooth dynamic path to addiction, caused by habit, disappears. Hence, the ability for smooth adjustment to relative price changes due to policies targeting obesity may not be applicable for a compulsive addict. We postulate the existence of thresholds past in which irreversible harm to addicted overeaters may occur. Reaching such states implies that no economic tools at our disposal could reverse the harm, which, in turn, deem that many policies directed at altering relative prices are ineffective in correcting overeating addiction and its consequences.

Even if we believe in consumer sovereignty, it is possible to shape consumer behavior via policy actions, including the behavior of extremum seekers turned addicts. The public policy of obesity should consider, in this case, its social cost.

No prior research has considered food addiction in light of compulsive eating caused by extremum-seeking behavior. Addiction correcting food policies always relied on either rational or myopic addiction models.

This paper aims to propose a scenario-based approach for measuring interest rate risks. Many regulatory capital standards in banking and insurance make use of similar approaches. The authors provide a theoretical justification and extensive backtesting of our approach.

The authors theoretically derive a scenario-based value-at-risk for interest rate risks based on a principal component analysis. The authors calibrate their approach based on the Nelson–Siegel model, which is modified to account for lower bounds for interest rates. The authors backtest the model outcomes against historical yield curve changes for a large number of generated asset–liability portfolios. In addition, the authors backtest the scenario-based value-at-risk against the stochastic model.

The backtesting results of the adjusted Nelson–Siegel model (accounting for a lower bound) are similar to those of the traditional Nelson–Siegel model. The suitability of the scenario-based value-at-risk can be substantially improved by allowing for correlation parameters in the aggregation of the scenario outcomes. Implementing those parameters is straightforward with the replacement of Pearson correlations by value-at-risk-implied tail correlations in situations where risk factors are not elliptically distributed.

The paper assumes deterministic cash flow patterns. The authors discuss the applicability of their approach, e.g. for insurance companies.

The authors’ approach can be used to better communicate interest rate risks using scenarios. Discussing risk measurement results with decision makers can help to backtest stochastic-term structure models.

The authors’ adjustment of the Nelson–Siegel model to account for lower bounds makes the model more useful in the current low-yield environment when unjustifiably high negative interest rates need to be avoided. The proposed scenario-based value-at-risk allows for a pragmatic measurement of interest rate risks, which nevertheless closely approximates the value-at-risk according to the stochastic model.

This article identifies serious weaknesses in various commonly used methods of measuring “average” growth rates over several time periods. An alternative method is proposed which satisfies two essential criteria: firstly it smoothes the data to remove “exceptional variation” in the time series, and secondly, it incorporates a compounding process which, it is suggested, is an essential requirement of a “correct” average growth rate.

To develop a new method for computer‐based 3D construction of garment basic cut on a computer generated body model.

The method has been developed on an example of a 3D garment basic cut construction on a virtual body model, determining the position of characteristic 3D points necessary for computer‐based definition of 3D cutting pattern contour segments. Contour segments modelling, as well as the modelling of 3D cut surfaces has been done using the NURBS objects.

A 3D garment cut has been constructed, such that matches physical characteristics of the body in question and offers the necessary comfort of the cut. The surface of the 3D cut has been divided into individual 3D cutting patterns.

The method has been developed on an example of a 3D garment basic cut construction of a single paper of clothing. However, the same principles can be applied and developed for any garment basic cut.

The 3D garment cut constructed can be further transformed into a network of polygons. Introducing fabric physical‐chemical properties fabric drape can be simulated, aiming at more realistic visualisation and further assessment of the garment fit. The 3D cutting patterns developed can be, applying computer‐based application of the mathematical models, transformed into 2D cutting patterns.

As compared to the methods developed by some previous investigations, the newly developed method offers the construction of garment 3D cut on a computer‐generated body model, granting the necessary comfort of the cut, which also means garment fitted to individual body characteristics. The 3D cut constructed can also be used as a starting point to define 2D cutting patterns in the following step, which will be matched to the physical characteristics of the model body, in the same way as the initial 3D cut.