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Solar photovoltaic, as a new type of energy, is a clean, efficient energy that China strongly encourages and supports to use. With the proposal of the “Carbon-neutral” and “Carbon-peak” strategic goals, China’s photovoltaic power generation industry has developed rapidly in recent years. In order to support the development of China's photovoltaic power generation industry, both central and regional governments issued policies and measures. However, there are also some problems such as incomplete policies, monopoly of upstream enterprises, the inability of mutual transmission among various places, photovoltaic cell consumables and recycling. In order to solve the above problems, this paper focuses on the development background and characteristics of the solar photovoltaic power generation industry, systematically expounds on the evolution process of China’s photovoltaic energy generation industry policies at the national and local levels, and finds that the characteristics of the policies issued in the photovoltaic field in China are that subsidy policies dominate, and there are many subsidy policies aimed at the mid-stream and down-stream of the industrial chain. Besides that, there are also few policies for photovoltaic transmission between different places; In terms of benefits, the installed capacity of photovoltaic power generation in China has gradually increased, and the environment in China has indeed improved, but the upstream of the industrial chain has obvious interest concentration and monopoly. Therefore, this paper puts forward several policy recommendations to accelerate the high-quality development of China’s photovoltaic industry.

In order to promote the sustainable development of architectural industrialization, it is necessary to evaluate its development level, identify the development status and key restricting factors, and achieve the effect of “promoting the development by evaluation”. However, the existing studies are mostly limited to the scope of provinces and cities, and there are few studies on the construction industrialization of an economic circle as a whole. Therefore, this paper locates the research within the scope of the region, constructs the evaluation model of the sustainable development level of the regional construction industrialization, and selects the Beijing-Tianjin-Hebei region as a case study. The research shows that the sustainable development level of construction industrialization in the Beijing-Tianjin-Hebei region is in the middle level, which needs to be improved from the aspects of economic support, technological innovation, and management. This paper provides a reasonable reference for how to evaluate and better promote the sustainable development of regional construction industrialization.

Under atmospheric pressure, the density, viscosity and speed of sound of the binary system of octamethylcyclotetrasiloxane (D4) with diesel fuel’s main components n-decane, n-dodecane, n-tridecane and n-tetradecane were measured at T = 288.15 to 328.15 K. The excess molar volume, viscosity deviation, excess Gibbs activation energy of viscous flow, isobaric thermal expansivity and isentropic compressibility deviation were calculated from the experimental data. The results indicate that the interactions among mixed systems are somewhat weaker than those in pure components.

The surface properties of nanoparticles affect their fate in biological systems. Based on nanotechnology and its methodology, pioneering studies have explored the effects of chemical surface patterns on the behavior of nanoparticles and provided many new insights into nano-bio interfaces. In this review, we would like to provide a summary of how the nanoparticle surface pattern modulates its biological effects. The relationship between the surface pattern of nanoparticles and the generated interaction with cell membranes, recognition of viruses and adsorption of proteins was discussed. On this basis, we believe that a reasonable design of the surface microstructure will promote the application of artificial nanoparticles in biomedicine and provide a new strategy for improving the design of nano-drug carriers.

Recent advances in hardware technologies raise new opportunities for architecting storage systems to exploit emerging NVRAM memory devices, fast remote-memory RDMA networking, and large numbers of processor cores. In this paper, we present Telepathy, a novel data access protocol for a distributed key-value storage system constructed around NVRAM and RDMA. Telepathy supports replicated data storage for fault tolerance and guarantees strong consistency while supporting high-volume concurrent read/write access from multiple client nodes. Our read protocol can perform largely silent consistent reads from any of the replica nodes holding an object, while our write protocol exploits remote atomic and non-volatile buffers to silently perform write contention resolution. Our experiments on an RDMA-enabled cluster using YCSB benchmarks show that Telepathy can achieve microsecond-range reads and writes with small tail latencies, GB-range data access bandwidth with small CPU utilization, and data consistency guarantees.

A wet and dry dual-purpose dust reduction device was developed to reduce the level of harm caused to mineworkers by the respirable dust generated in a fully mechanized working face in a coal mine, and specifically those workers located in the return airway [1]. First, spraying experiments were carried out to generate data showing an efficient dust reduction effect. Then, the data obtained from the experiments were imported into computational fluid dynamics (CFD) software for the numerical simulation of spraying [2]. The influence of the outward extension distance of the nozzle (Ls) and the spraying pressure (Pw) on the coverage capacity of the dust capture mesh and the distribution of the spray field was determined. According to the experiments, the optimal nozzles were 2.4-mm round-orifice nozzles with X-shaped flow guide cores. When Ls = 25 cm and Pw = 7 MPa, the spray field covered the dust capture mesh to the greatest degree, and effective dust reduction was achieved. Field application and measurements were carried out in the return airway of the 117 fully mechanized working face of Jinjitan Coal Mine, China. The dust reduction efficiency was found to reach 90.25%. Following the reduction in dust, the concentrations of respirable dust in the return airway at distances of 20, 50, and 80 m from the fully mechanized working face were 0.250, 0.203, and 0.179 mg/m3, respectively. As a result, the dust pollution problem in the return airway was effectively solved, and the airway environment was significantly improved.

Emerging nonvolatile RAM (NVRAM) technologies have a limit on the number of writes that can be made to any cell, similar to the erasure limits in NAND Flash. This motivates the need for wear leveling techniques to distribute the writes evenly among the cells. Unlike NAND Flash, cells in NVRAM can be rewritten without the need for erasing the entire containing block, avoiding the issues of space reclamation and garbage collection, motivating alternate approaches to the problem. In this article, we propose a hierarchical wear-leveling model called Ouroboros wear leveling. Ouroboros uses a two-level strategy whereby frequent low-cost intraregion wear leveling at small granularity is combined with interregion wear leveling at a larger time interval and granularity. Ouroboros is a hybrid migration scheme that exploits correct demand predictions in making better wear-leveling decisions while using randomization to avoid wear-leveling attacks by deterministic access patterns. We also propose a way to optimize wear-leveling parameter settings to meet a target smoothness level under limited time and space overhead constraints for different memory architectures and trace characteristics. Several experiments are performed on synthetically generated memory traces with special characteristics, two block-level storage traces, and two memory-line-level memory traces. The results show that Ouroboros wear leveling can distribute writes smoothly across the whole NVRAM with no more than 0.2% space overhead and 0.52% time overhead for a 512GB memory.

Providing latency support is an important problem for clustered storage systems. In this paper, we present Fair-EDF, a framework for latency guarantees in shared storage servers. It provides fairness control while supporting latency guarantees. Fair-EDF extends the pure earliest deadline first (EDF) scheduler by adding a controller to shape the workloads. Under overload it selects a minimal number of requests to drop and to choose the dropped requests in a fair manner. The evaluation results show Fair-EDF provides steady fairness control among a set of clients with different runtime behaviors.

The paper addresses the problem of providing performance QoS guarantees in a clustered storage system. Multiple related storage objects are grouped into logical containers called buckets, which are distributed over the servers based on the placement policies of the storage system. QoS is provided at the level of buckets. The service credited to a bucket is the aggregate of the IOs received by its objects at all the servers. The service depends on individual time-varying demands and congestion at the servers. We present a token-based, coarse-grained approach to providing IO reservations and limits to buckets. We propose pShift, a novel token allocation algorithm that works in conjunction with token-sensitive scheduling at each server to control the aggregate IOs received by each bucket on multiple servers. pShift determines the optimal token distribution based on the estimated bucket demands and server IOPS capacities. Compared to existing approaches, pShift has far smaller overhead, and can be accelerated using parallelization and approximation. Our experimental results show that pShift provides accurate QoS among the buckets with different access patterns, and handles runtime demand changes well.

Objective To describe Chinese older adults’ willingness to enter long-term care facilities and to examine individual factors associated with the willingness of using this growing model of long-term care in China. Methods A cross-sectional study involving a random sample of 670 adults aged 60+ in the Hezuo community in Chengdu, China in 2016. Respondents were interviewed by trained staff on socio-demographics, health status, quality of life, social support, and willingness to enter long-term care facilities. Results Only 11.9% of the respondents were willing to enter long-term care facilities for meeting their medical and social service needs. Multivariable logistic regression analysis showed that willingness to enter long-term care facilities was associated with higher household income (OR = 4.55, 95% CI:1.72–12.00), insurance of Urban Resident Basic Medical Insurance (OR = 4.80, 95% CI:1.17–19.67) and unemployment (OR = 0.48, 95% CI:0.24–0.99). Among those who were willing to enter long-term care facilities, an overwhelming majority (81.2%) would prefer going to a facility within 30-minute walking distance from their current residence, 82.5% indicated the need of nursing care, and 90.0% expected a partnership between the long-term care facility and a large hospital. Conclusions A minority of older Chinese were willing to receive long-term care delivered at a facility within walking distance from their current residence. Recent policy aimed at increasing the supply of long-term care facilities may not be consistent with consumer preference for home and community-based care. Balancing investment between home and community-based care, and establishing long-term care insurance remain the top priorities for long-term care research and policy development in China.

A Łojasiewicz-type estimate is a powerful tool in studying the rigidity properties of the harmonic map heat flow. Topping proved such an estimate using the Riesz potential method, and established various uniformity properties of the harmonic map heat flow from $\mathbb{S}^{2}$ to $\mathbb{S}^{2}$ (J. Differential Geom. 45 (1997), 593–610). In this note, using an inequality due to Sobolev, we will derive the same estimate for maps from $\mathbb{S}^{2}$ to a compact Kahler manifold N with nonnegative holomorphic bisectional curvature, and use it to establish the uniformity properties of the harmonic map heat flow from $\mathbb{S}^{2}$ to N, which generalizes Topping’s result.

Let Ω be a bounded smooth domain in R 2 n ( n ≥ 2 ). In this note, we consider the functional J ρ ( u ) = 1 2 ∫ Ω | ( − Δ ) n / 2 u ( x ) | 2 d x − ρ log ∫ Ω h ( x ) e u ( x ) d x . Suppose h ( x ) is a smooth function with 0 a ≤ h ( x ) ≤ b . Then, using the idea of Lin and Wei [C. Lin, J. Wei, Locating the peaks of solutions via the maximum principle II: A local version of the method of moving planes, Comm. Pure Appl. Math. LVI (2003) 784–809], we prove the existence of minimizers of J ρ for any ρ ≤ ρ 2 n = 2 2 n n ! ( n − 1 ) ! ω 2 n in a space of functions H = H n ( Ω ) ∩ { u , ( − Δ ) j u ∈ H 0 1 ( Ω ) , j = 1 , 2 , … , [ n − 1 2 ] } , where ω 2 n is the area of the unit sphere S 2 n − 1 in R 2 n .