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Marker-Assisted Selection (MAS) pyramiding breeding combined with traditional breeding techniques has become an important method for molecular breeding in wheat. In recent years, with the continuous discovery of disease-resistance genes and the development of molecular markers associated with related genes in wheat, the research of MAS pyramiding disease-resistance genes has made great progress. The progress on the study of MAS pyramiding resistance genes in wheat powdery mildew, rust, and Fusarium head blight (Fhb) was reviewed. The aims of pyramiding breeding were discussed in order to promote the research on MAS pyramiding breeding in wheat.

Differential privacy protection model provides strict and quantitative risk representation for privacy disclosure, which greatly ensures the availability of data. However, most existing methods do not consider the semantic context, so they are vulnerable to attacks based on semantic information. Therefore, dynamic social privacy protection based on graph pattern partitioning is designed to satisfy differential privacy protection. Firstly, the structure of social network is represented as a graph model, and the original graph is classified into several sub-graphs according to the characteristics of nodes. Then, the dense area of each sub-graph is divided by quad-tree method, and the noise of differential privacy protection is added to the leaf nodes of the tree, and the graph publishing is generated by sub-graph reconstruction. Finally, the feasibility and practicability of the model are verified by statistical analysis, such as degree distribution, shortest path, and clustering coefficient. The simulation results show the validity and applicability of the privacy protection method proposed in this paper.

The radiant heating system assisted by an air source heat pump has been widely applied in China for its effective energy conservation, high comfort performance and flexible utilization. Because the coefficient of performance of the system is strictly controlled by the supply water temperature heated by the air source heat pump, an efficient radiant terminal with low-temperature supply water is of significance to the coefficient of performance. In this research, the energy-saving feature of the capillary mat radiant heating system was first proved theoretically based on the influence of the heat transfer temperature difference on the coefficient of performance of the air source heat pump. In order to compare the performances of the capillary mat radiant and floor radiant heating systems, an experiment platform of two different radiant terminals assisted by an air source heat pump was established in a residential building in Xi’an, China. Experimental results showed that, to satisfy the indoor heating requirements, the supply and return water temperatures ought to be 35.0℃ and 30.9℃, respectively, and for the capillary mat radiant heating system, 43.9℃ and 38.8℃, respectively, for the floor radiant heating system. However, the electricity consumption of the capillary mat radiant heating system is 45% less than that of the floor radiant heating system. Thus, our study validated the energy-saving potential of the capillary mat radiant heating system assisted by an air source heat pump.

Archaeology museums play an important role in protecting unearthed cultural relics from natural weathering. However, many of the unearthed relics are still suffering from deterioration or even ruin due to improper environmental control in archaeology museums. In this study, we demonstrate that the disregard of environmental control for relics and the imbalances of energy and mass across in situ air-relic-soil interfaces in pits are important causes for the deterioration of relics. Thus, individual environmental management strategies for visitor passages and relic preservation are proposed for the long-term preservation of unearthed relics. Experimental investigations using the test pit, with radiant panels for control of the environmental interfaces, validated these management strategies for the preservation and display of relics in archaeology museums. These results have significant implications for understanding the mechanism of relic deterioration and for formulating appropriate strategies to create sustainable environments for long-term preservation of unearthed relics in archaeology museums.

Perceived air quality is an important aspect in current guidelines and standards for indoor environment. It represents occupants’ real feeling about indoor air and affected by almost all environmental parameters, such as the temperature, the relative humidity, the air movement, and et al. Studies were conducted mainly in controlled climate chambers or air-conditioned spaces, rarely in natural ventilated spaces. In this paper, the effects of temperature and air movement on perceived air quality in natural ventilated classrooms are investigated. The indoor environmental parameters in 7 classrooms for 35 lessons are continuously measured and the students in class are asked to report their perception on the temperature, air movement, and the air quality of classrooms by filling questionnaires at once after a lesson. The number of received validated questionnaires is 992. The correlation analysis is used to investigate the effects of temperature and air movement on the perceived air quality. Results show that in natural ventilation classrooms, which are warm at temperature and moderate at humidity with an air speed lower than 0.1m/s, it is the thermal sensation rather than the temperature, enthalpy, thermal acceptability, or CO2 concentration that affects the perception of occupants for air quality. The perception for air movement influences the air quality acceptability. Increasing air movement increases the air quality acceptability. Besides, it is found that the preference of air movement is related to the air quality acceptability. When participants feel that the air movement is just suitable, the acceptability of air quality reaches the highest. When participants feel the air movement need to be adjusted, the air quality acceptability decreases.

Thermal comfort of students in university classrooms during transition season in Xi'an, before heating, is studied. Indoor thermal environment parameters and outdoor weather parameters of seven typical classrooms in a university campus in Xi'an were measured. At the same time, the subjective questionnaires were used to know students' satisfaction and expectation with various environmental factors. 992 valid questionnaires were received. Based on the data collected, the thermal comfort of occupants in classroom was discussed and a thermal comfort adaptive model was established. The results show that the range of thermal comfort acceptable to students is broader than that defined in the ASHARE standard, indicating that students have some adaptability to indoor air environment. The measured indoor thermal neutral temperature is lower than the theoretical one. There is difference between the thermal sensation vote (TSV) and the predicted mean vote (PMV). The slope of TSV cure vs. operative temperature is greater than that of PMV, indicating that under actual condition, students are more sensitive to air changes. The proposed adaptive model provided a reference for understanding the thermal comfort of university buildings under natural ventilation environment in Xi’an, helpful to improve the thermal comfort and save energy for university buildings in Xi’an.

With an increase of building energy consumption, the requirement of building energy conservation becomes a key importance of national energy development. It's not feasible to apply the traditional method to predict and analyze energy consumption in relics museums like the Emperor Qin's Terra-Cotta Warriors and Horses Museum at Xi’an City, China, due to the particularities of soil and building structures. This paper uses commercial software DeST to analyze the building energy consumption by estimating building cooling and heating loads hourly. The single factor method is used to analyze the affection of load influential factors and the average unit change value and rate method is used to analyze the factor levels. The predicted results show that the simulated building possesses considerable energy saving potential. In addition, the significance of various loading impact factors is further discussed.

Dust devils are common but meteorologically unique phenomena on Earth and on Mars. The phenomenon produces a vertical vortex motion in the atmosphere boundary layer and often occurs in hot desert regions, especially in the afternoons from late spring to early summer. Dust devils usually contain abundant wind energy, for example, a maximum swirling wind velocity of up to 25 m/s, with a 15 m/s maximum vertical velocity and 5 m/s maximum near-surface horizontal velocity can be formed. The occurrences of dust devils cannot be used for energy generation because these are generally random and short-lived. Here, a concept of sustained dust-devil-like whirlwind is proposed for the energy generation. A prototype of a circular shed with pre-rotation vanes has been devised to generate the whirlwind flow by heating the air inflow into the circular shed. The pre-rotation vanes can provide the air inflow with angular momentum. The results of numerical simulations and experiment illustrate a promising potential of the circular shed for generating swirling wind energy via the collection of low-temperature solar energy.

Immovable historical relics in some archeology museums of China suffer deterioration due to their improper preservation environment. The existing environmental control systems used in archeology museums are often designed for the amenities of visitors, and these manipulated environments are often inappropriate for the conservation of abiotic relics. This paper points out that the large open space of the existing archeology museum could be a cause of deterioration of the relics from the point of view of indoor air convective flow. The paper illustrates the need to introduce a local pit environmental control, which could reintegrate a pit primitive environment for the preservation of the historical relics by using an air curtain system, orientated to isolate the unearthed relics, semiexposed in pits to the large gallery open space of the exhibition hall.