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The Chinese work point system was a series of labor organization rules and regulations used for the calculation of the amount and quality of labor and for determining the form of labor organization. The history of the work point system is thus the history of China’s agricultural collectivization. In this book we analyse how these work points were allotted, how they provided, or impaired, labor incentives, and if they leave open the possibility for income mobility.

Modern power systems, from continent-spanning networks down to isolated microgrids, are experiencing unprecedented technological changes with broader use of direct current (dc) in addition to traditional alternating current (ac). Such integrated ac-dc power systems present notable challenges in all aspects of design, analysis, control, and operation, where extensive computer simulations play the essential and enabling role. Due to the use of diverse types of signal representation and component formulation, state-of-the-art power system simulation tools are limited to their distinct time scales of transient phenomena. This thesis considers the dynamic phasor (DP) type modelling approaches, where two types of DP theories, namely the shifted-frequency analysis (SFA) and the generalized averaging method (GAM), are considered. In DP-type simulations, power systems are modelled using analogous low-pass time-phasor signals, thereby offering flexible selection of time-step sizes and superior combination of numerical accuracy and efficiency. The ultimate goal of this research is to increase the numerical efficiency of DP-type simulations for the integrated ac-dc power systems. This is achieved by proposing several new DP component models with desirable features and improved numerical properties. First, the constant-parameter SFA model of synchronous machines is proposed to avoid numerically-costly recalculations of the time-varying stator-network matrices. This model is then extended to induction machines for modelling in state-variable based (SV-based) simulation tools. Next, we propose a new, highly efficient model of line-commutated rectifiers using a parametric DP formulation, which is demonstrated as valid for various system operating conditions. Moreover, the effect of ac side harmonics is incorporated to improve modelling fidelity. Finally, the interface between SFA- and GAM-type DPs is achieved to interconnect the proposed DP models. Rigorous case studies demonstrate the superior numerical efficiency of the proposed models, and their advantageous accuracy in capturing the desired phenomena of ac-dc power systems. It is envisioned that the proposed models will become highly useful to many researchers and engineers worldwide, and facilitate the development of next-generation power system simulation tools.

PurposeThe purpose of this paper is to draw conclusions about China's agricultural integration (CAI) by looking back its processes stage by stage, discussing the problems related to CAI, in order to learn salutary lessons for the future of agricultural development, for the increase in rural income, and especially for the promotion of CAI.Design/methodology/approachThe paper comprises three stages: analyzing the process of CAI from the household responsibility system, to agricultural industrialization, until the stage of CAI led by farmers' co‐operatives; discussing the related practice together with literature; and historically proving that there is no better way to promote CAI than letting it be led by farmers' co‐operatives.FindingsThe paper finds that, the development of China's agricultural economic organizations is owing to CAI, and can be studied stage by stage; the process of CAI proves that it needs to be promoted as a new style led by farmers' co‐operative in order to increase rural income; literature review also gives eloquent proof of the above viewpoint; agricultural integration led by farmers' co‐operative should be taken as a better way to upgrade CAI and to increase rural income, for it can decrease the benefit disputes that usually happened in the former type of agricultural industrialization.Originality/valueThe obvious value of the paper is to show, by a historical review, a way to promote CAI and to increase farmers' income. A literature review finds these countermeasures comprehensively, historically, and theoretically. The information about CAI will be beneficial for people who are interested in the topic.

With For a large number of incomplete fault data, the traditional artificial intelligence methods based cannot effectively and timely analysis or can not be accurately diagnosed or misdiagnosed because of the ill-conditioned problem caused by inefficient discretization approaches. A method based on rough set theory integrated with improved artificial fish-swarm algorithm (IAFSA) was presented in this paper for fault diagnosis of transformer. Firstly, the values of dissolved gas-in-oil analysis (DGA) were taken as conditional attributes and the type faults were taken as decision attributes. Various relations between fault and symptom were connected and decision table was established. the improved artificial fish-swarm algorithm is used to discrete continuous attribute; then, using the rough set theory to reduce the decision table. The simplified decision rules were got, which greatly simplifies the difficulty of diagnosis The experimental results indicate that the method has increased the diagnosis accuracy compared with traditional algorithm.