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Forecasting the future movement of yield curves contains valuable information for both academic and practical issues such as bonding pricing, portfolio management, and government policies. The purpose of this paper is to develop a dynamic factor approach that can provide more precise and consistent forecasting results under various yield curve dynamics.

The paper develops a unified dynamic factor model based on Diebold and Li (2006) and Nelson and Siegel (1987) three-factor model to forecast the future movement yield curves. The authors apply the state-space model and the Kalman filter to estimate parameters and extract factors from the US yield curve data.

The authors compare both in-sample and out-of-sample performance of the dynamic approach with various existing models in the literature, and find that the dynamic factor model produces the best in-sample fit, and it dominates existing models in medium- and long-horizon yield curve forecasting performance.

The authors find that the dynamic factor model and the Kalman filter technique should be used with caution when forecasting short maturity yields on a short time horizon, in which the Kalman filter is prone to trade off out-of-sample robustness to maintain its in-sample efficiency.

Bond analysts and portfolio managers can use the dynamic approach to do a more accurate forecast of yield curve movements.

The enhanced forecasting approach also equips the government with a valuable tool in setting macroeconomic policies.

The dynamic factor approach is original in capturing the level, slope, and curvature of yield curves in that the decay rate is set as a free parameter to be estimated from yield curve data, instead of setting it to be a fixed rate as in the existing literature. The difference range of estimated decay rate provides richer yield curve dynamics and is the key to stronger forecasting performance.

The study aims to examine the effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel.

Fatigue behavior of 34Cr2Ni2Mo steel was investigated for up to 1E10 cycles.

Results showed that both inclusion and inherent microstructure have an influence on the crack initiation mechanism. Fatigue cracks mostly initiated from inclusions, whereas substrate-induced crack initiations were also observed. Fatigue life of inclusion-induced failures is mostly determined by the location of inclusions rather than the loading stress. The inherent microstructure seems to tolerate inclusions at a lower stress level in very high-cycle regime owing to the absence of internal inclusion-induced failure. For the substrate-induced crack initiations, high-density dislocations are found to be accumulated around the carbide particle-matrix interface, which may be the cause of crack initiation in the inherent structure due to strain localization.

The effect of inclusions and inherent microstructure on fatigue behavior of 34Cr2Ni2Mo steel up to 1E10 cycles.

Highlights

• Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

• Surface inclusion induced premature failures.

• Inherent microstructure tolerates inclusions at lower stress level.

• Internal carbides promote substrate-induced crack initiations.

Fatigue failure occurs even at a lifetime of 5.76E9 cycles.

Surface inclusion induced premature failures.

Inherent microstructure tolerates inclusions at lower stress level.

Internal carbides promote substrate-induced crack initiations.

The investigations provide a basis for the optimization of the alloy 6061-T6 friction stir welding (FSW) process to improve the mechanical properties of welded joints.

The local deformation of the FSW joint in tension and fatigue test were experimentally investigated by digital image correlation (DIC) technique.

The local stress-strain behaviors of the sub-regions show that the plastic strain always concentrated at the heat affected zone (HAZ) on the advancing side both in tension and high cycle fatigue and eventually leads to the final fracture. The evolution of the plastic strain at very low stress is extremely slow and accounts for most of the total fatigue life. However, the local deformation exhibits a sudden increase just before the fatigue failure.

Based on the experimental data, the result indicates that the HAZ is the weakest zone across the weld and the strain localization in high cycle fatigue is very harmful and unpredictable for the FSW joints.

The development of tourism around Wolong Nature Reserve changes the local communities' ways of life. This study discusses how ecotourism affects the households' use of their capitals, the livelihood strategies as well as illustrates the impact on the habitats in the reserve through Department for International Development’s (DFID) Sustainable Livelihood Framework (SLF) with data collected during fieldwork.

The study focuses on (1) Calculating Livelihood Capital Index. (2) The effects of livelihood capitals on livelihood strategy were calculated by multinomial logistic regression.

The study has yielded the following results: (1) In general, tourism promotes people's livelihood capitals. The growth in different types of households under tourism settings is ranked as full-time tourism operators > part-time tourism operators > traditional living households. (2) Tourism development mainly shifts livelihood strategies in two ways. Firstly, travel operating replaces some traditional practices that make livings; secondly, increased needs for potherbs and herbs from tourists let households enter into the hills to pick the plants more actively, which intensifies the destruction of giant panda's habitats. (3) Nine types of livelihood capitals indicators, namely farmland quality, distance between house and roads, number of laborers, average housing area, average income per person, whether family members being village cadres, and ever having received skills training shape livelihood strategies in different levels.

Three discussions are drawn from the study: (1) Enhancing the exploit for tourism resources to form a diversified competition. (2) Introducing herb growing to fulfill tourists' needs and improve people's livelihood in the meantime. (3) Optimizing the tourism surveillance and management system and improving the rules and regulations.

The purpose of this paper is to determine (1) the relationship between microstructure and fatigue cracking behavior and (2) effect of rolling on the process of crack initiation and propagation in FeCrAl alloys.

The qualitative and quantitative fracture studies were performed using scanning electron microscopy and the non-contact optical measurement system (IFMG5).

The results show that the formation of facets, rough facets and parallel stripes in the crack initiation and early crack propagation zones are closely related to the sensitivity of crack behavior to the microstructure of the material. Besides, the rolling process has a significant influence on the small crack initiation and propagation behavior. Quantitative analysis demonstrates that the size of the stress intensity factor and plastic zone size in the rough zone is associated with the rolling process.

The findings of this study have the potential to enhance the understanding of the microstructural crack formation mechanisms in FeCrAl alloys and shed light on the impact of rolling on the long-term and ultra-long fatigue behavior of these alloys. This new knowledge is vital for improving manufacturing processes and ensuring the safety and reliability of FeCrAl alloys used in nuclear industry applications.

The main objectives of collective forest tenure reform in China are to stimulate rural households to invest in forestry management, protect the ecosystem and improve their livelihood. By constructing the unbalanced panel data of household investment, this study discusses the dynamic changes and influencing factors of household investment, which will lay a foundation for further research and provide a reference for decision-making.

Based on 3,500 samples from rural households in the provinces of Fujian, Hunan, Yunnan, Shaanxi, Jiangxi, Gansu, and Liaoning collected during field investigations from 2010 to 2015, this study conducts an empirical analysis of the household investment in forestry management and its factors with nonbalanced panels.

According to the analysis, the average investment in forestry management per household from 2010 to 2015 fluctuates greatly; the age of the householder, increased forestry area, subsidies, joining professional cooperatives, and forest tenure mortgage show positive effects on achieving the objectives.

The discussions are drawn from the study that supporting policies such as the forest tenure transfer system, professional cooperatives, financial services and subsidies should be further improved to sustain a positive in the forestry industry.

As an advanced calculation methodology, reliability-based multidisciplinary design optimization (RBMDO) has been widely acknowledged for the design problems of modern complex engineering systems, not only because of the accurate evaluation of the impact of uncertain factors but also the relatively good balance between economy and safety of performance. However, with the increasing complexity of engineering technology, the proposed RBMDO method gradually cannot effectively solve the higher nonlinear coupled multidisciplinary uncertainty design optimization problems, which limits the engineering application of RBMDO. Many valuable works have been done in the RBMDO field in recent decades to tackle the above challenges. This study is to review these studies systematically, highlight the research opportunities and challenges, and attempt to guide future research efforts.

This study presents a comprehensive review of the RBMDO theory, mainly including the reliability analysis methods of different uncertainties and the decoupling strategies of RBMDO.

First, the multidisciplinary design optimization (MDO) preliminaries are given. The basic MDO concepts and the corresponding mathematical formulas are illustrated. Then, the procedures of three RBMDO methods with different reliability analysis strategies are introduced in detail. These RBMDO methods were proposed for the design optimization problems under different uncertainty types. Furtherly, an optimization problem for a certain operating condition of a turbine runner blade is introduced to illustrate the engineering application of the above method. Finally, three aspects of future challenges for RBMDO, namely, time-varying uncertainty analysis; high-precision surrogate models, and verification, validation and accreditation (VVA) for the model, are discussed followed by the conclusion.

The scope of this study is to introduce the RBMDO theory systematically. Three commonly used RBMDO-SORA methods are reviewed comprehensively, including the methods' general procedures and mathematical models.

Engineering components/structures with geometric discontinuities normally bear complex and variable loads, which lead to a multiaxial and random/variable amplitude stress/strain state. Hence, this study aims how to effectively evaluate the multiaxial random/variable amplitude fatigue life.

Recent studies on critical plane method under multiaxial random/variable amplitude loading are reviewed, and the computational framework is clearly presented in this paper.

Some basic concepts and latest achievements in multiaxial random/variable amplitude fatigue analysis are introduced. This review summarizes the research status of four main aspects of multiaxial fatigue under random/variable amplitude loadings, namely multiaxial fatigue criterion, method for critical plane determination, cycle counting method and damage accumulation criterion. Particularly, the latest achievements of multiaxial random/variable amplitude fatigue using critical plane methods are classified and highlighted.

This review attempts to provide references for further research on multiaxial random/variable amplitude fatigue and to promote the development of multiaxial fatigue from experimental research to practical engineering application.

The purpose of this paper is to propose a model explaining the roles of right-hand person and the factors contributing to the successful relationship between the top executive and the right-hand person.

In-depth qualitative case studies are conducted. Longitudinal observations, interviews with six right-hand persons and the top executives in three organizations are conducted to test the propositions of the model.

Results indicate that different types of congruence between the top executive and the right-hand person are required when the right-hand person is performing the roles of an implementer and joint decision maker.

This study extends the leadership literature by investigating the phenomenon of right-hand person of the top executive, which has seldom been studied systematically or scientifically. It provides insights and serves as a stepping stone for future research in this area. One key limitation is that it is a qualitative study with limited samples under investigation.

Practical implications concerning how to build up a successful relationship between the top executive and the right-hand person can be drawn from the proposed model. Insight concerning how to collaborate between the top executive and the right-hand person can be drawn from the in-depth case analyses.

The phenomenon of right-hand person is not limited to business organizations. The collaboration between the key decision maker and his chief assistant should be applicable to other contexts such as non-government organizations.

To the best of the knowledge, this is the first paper that investigates the right-hand person phenomenon in the literature. As the right-hand person of the top executive can have important influence on organizational performance, the study may serve as the stepping stone for further understanding of this important phenomenon.

The purpose of this paper is to examine the relationship between accounting and the early roots of the nation‐state in mid nineteenth‐century Siam/Thailand.

First, the paper examines the theoretical inter‐relationship between accounting and nationalism. Second, it relates this theoretical understanding to a study of the changing concepts, methods and structures of indigenous Siamese accounting at a time of transition when foreign mercantile influence was beginning to have an impact on the mid nineteenth^‐century Siamese economy. Third, the paper analyses how these accounting structures and practices came to constitute a socio‐political instrument, which contributed to the administrative development of a Siamese dynastic state by the mid nineteenth‐century. Finally, the paper studies the ways in which this dynastic state began to promote national characteristics through the use of its accounts to create a sense of Siamese cultural identity.

The findings emphasise the important role of accounting in the construction of political and national identity.

This inter‐disciplinary paper highlights a general neglect in the accounting literature of the instrumental role of accounting in nation‐state formation as well as offering a re‐interpretation of Thai historiography from an accounting viewpoint. Moreover as an example of alternative accounting practice, this paper provides an analysis of indigenous accounting methods and structures in mid nineteenth‐century Siam/Thailand at the point when they were becoming increasingly influenced by foreign mercantilism.