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71.
Blockchain possesses the potential of transforming global supply chain management. Gartner predicts that blockchain could be able to track $2?T of goods and services in their movement across the globe by 2023, and blockchain will be a more than $3 trillion business by 2030. Nowadays, a growing number of blockchain initiatives are disrupting traditional business models in each sector. In this paper, we provide a timely and holistic overview of the state-of-the-art, challenges, gaps and opportunities in global supply chain and trade operations for both the private sector and governmental agencies, by synthesising a wide range of resources from business leaders, global international organisations, leading supply chain consulting firms, research articles, trade magazines and conferences. We then identify collaborative schema and future research directions for industry, government, and academia to jointly work together in ensuring that the full potential of blockchain is unleashed amidst the socioeconomic, geopolitical and technological disruptions that global supply chains and trade are facing. 相似文献
72.
Benhui Hu Christopher Berkey Timothy Feliciano Xiaohong Chen Zhuyun Li Chao Chen Shahrouz Amini Mui Hoon Nai Qun-Li Lei Ran Ni Juan Wang Wan Ru Leow Shaowu Pan Yong-Qiang Li Pingqiang Cai Ali Miserez Shuzhou Li Chwee Teck Lim Yun-Long Wu Teri W. Odom Reinhold H. Dauskardt Xiaodong Chen 《Advanced materials (Deerfield Beach, Fla.)》2020,32(12):1907030
Bacterial infections remain a leading threat to global health because of the misuse of antibiotics and the rise in drug-resistant pathogens. Although several strategies such as photothermal therapy and magneto-thermal therapy can suppress bacterial infections, excessive heat often damages host cells and lengthens the healing time. Here, a localized thermal managing strategy, thermal-disrupting interface induced mitigation (TRIM), is reported, to minimize intercellular cohesion loss for accurate antibacterial therapy. The TRIM dressing film is composed of alternative microscale arrangement of heat-responsive hydrogel regions and mechanical support regions, which enables the surface microtopography to have a significant effect on disrupting bacterial colonization upon infrared irradiation. The regulation of the interfacial contact to the attached skin confines the produced heat and minimizes the risk of skin damage during thermoablation. Quantitative mechanobiology studies demonstrate the TRIM dressing film with a critical dimension for surface features plays a critical role in maintaining intercellular cohesion of the epidermis during photothermal therapy. Finally, endowing wound dressing with the TRIM effect via in vivo studies in S. aureus infected mice demonstrates a promising strategy for mitigating the side effects of photothermal therapy against a wide spectrum of bacterial infections, promoting future biointerface design for antibacterial therapy. 相似文献
73.
A semiconductor distributor that plays a third-party role in the supply chain will buy diverse components from different suppliers, warehouse and resell them to a number of electronics manufacturers with vendor-managed inventories, while suffering both risks of oversupply and shortage due to demand uncertainty. However, demand fluctuation and supply chain complexity are increasing due to shortening product life cycle in the consumer electronics era and long lead time for capacity expansion for high-tech manufacturing. Focusing realistic needs of a leading distributor for semiconductor components and modules, this study aims to construct a UNISON framework based on deep reinforcement learning (RL) for dynamically selecting the optimal demand forecast model for each of the products with the corresponding demand patterns to empower smart production for Industry 3.5. Deep RL that integrates deep learning architecture and RL algorithm can learn successful policies from the dynamic and complex real world. The reward function mechanism of deep RL can reduce negative impact of demand uncertainty. An empirical study was conducted for validation showing practical viability of the proposed approach. Indeed, the developed solution has been in real settings. 相似文献
74.
为将我国最严格水资源管理制度的实践与二元水循环理论相结合,提高“三条红线”控制指标的科学性与合理性,本文以SWAT模型为基础,通过改进子流域划分方法、添加经济社会模块和人工用水模块,对其人工侧支循环模拟进行了系统的完善,开发了基于SWAT的水量-水质-水效联合调控模型SWAT_WAQER。以广西南流江流域为例,从国民经济用水量、河道径流与水质等方面对模型进行校验,并在此基础上划分了2030年“三条红线”控制指标。结果表明:该模型性能良好,能够用于不同节水情景下的国民经济用水量、污染物排放量、水功能区水质达标结果分析,可以作为科学制定“三条红线”控制指标的有力支撑工具。 相似文献
75.
Sanae Dahbi Abdelhak Aziz Abdelhafid Messaoudi Imane Mazozi Kamal Kassmi Naima Benazzi 《International Journal of Hydrogen Energy》2018,43(10):5283-5299
In this article, the authors design a new clean storage device for a photovoltaic system (PV) reinforced by the electrical grid. The photovoltaic system supplies power to a DC load. When the power of the photovoltaic source is insufficient, the electrical grid compensates the energy deficit. On the other hand, if the load is satisfied and the PV source is still able of supplying energy, the energy excess is diverted to an own storage unit materialized by an electrolysis which produces gaseous hydrogen by the process of electrolysis of water. The authors show that the quantity of hydrogen produced is proportional to the photovoltaic energy excess and also to the flow of water injected into the electrolysis. In this case, it is a question of designing an electrolysis with specific characteristics, which takes into account the quantity of energy excess and the flow of water injected into it. The authors abandon the idea of controlling the water flow by means of a pumping-electrovalve system, and initiate the idea of replacing the function of the pump by the action of gravity. The work focuses on the development of an electrolysis optimization approach using the water flow control in its alliance with the PV power excess which is also maximized. For an optimized use of the global system (load and electrolysis), the authors present an architecture based on energy-converting structures (DC/DC and AC/DC). In addition, to increase the reliability and safety of the system, the authors finish by developing a power management strategy (PMS) in the designed system. This power management strategy organizes the energy flow and selects the appropriate path of this flow between the two energy sources (PV and electrical grid) and the two possible energy receivers (load and electrolysis). A complete modeling of the system is developed in the Matlab/Simulink environment. The simulation results show that the hybrid system (PV and electrical grid) is able to permanently supplying the load and potentially storing the excess of the PV energy in the form of hydrogen gas. 相似文献
76.
基于典型故障案例的阐述和故障原因分析,归纳总结了船舶柴油机燃油系统在日常使用和管理中应注意的问题,可为船舶操作人员和管理人员提供参考。 相似文献
77.
We consider a small traditional retailer that is managing its inventory under strict cash constraints, mainly because typically informal loans are offered to customers. These stores are widely present in emerging markets, and we refer to them as nanostores (also called ‘mom-and-pop stores’). As the suppliers require immediate payments for goods delivered, a nanostore can only replenish products to the level for which it has on-hand cash available. To improve delivery efficiency, a supplier might offer a nanostore credit for its replenishments. However, currently, suppliers are often reluctant to do so as these nanostores quickly go bankrupt or disappear, hence defaulting on all outstanding credits. The objective of this paper is to determine when it is beneficial to offer supplier credits. We propose a multi-period, stochastic inventory model, and numerically compare scenarios with and without supplier credits. Our study shows that even in the presence of this risk, suppliers often have good incentives to provide these credits, even if interest is not incurred. For this to hold, the operations of the retailer should be (a little) profitable in the first place, for which we provide analytical conditions. 相似文献
78.
全自动集装箱码头装卸系统集成了当今世界各项先进技术,在研发、制造、调试过程中,都要坚持质量第一、安全第一的原则,确保各项技术参数可靠,设备运行稳定。在总结国内几个全自动码头装卸系统的质量管理方法与经验的基础上,结合自动化码头自身特点,给出全自动集装箱码头装卸系统主要质量管理方法,进一步丰富发展自动化码头装卸系统建造过程中的“不欠债离岸”质量管理理念。 相似文献
79.
Energy management of hybrid photovoltaic (PV)-battery systems still serve as a challenging task owing to their complex and nonlinear characteristics, multicomponent structures, and the extensive range of environmental factors disturbing their nominal performance. The hybrid energy system developed in this study encompasses PV arrays, a battery component, one boost converter, and one bidirectional boost converter. In this paper, we propose a novel adaptive robust control framework for the optimal energy management of the PV-battery systems under many operating conditions and subject to unmodelled dynamics. An improved exponential-like adaptive integral sliding mode (EISM) control coupled to neural network approximator is introduced using a multi-rate convergence tweaking mechanism for the sliding surface to improve the transient performance of the closed-loop system. Furthermore, the entire dynamics of the hybrid energy system is considered unknown, unlike the previous studies that only assumed the parametric uncertainties. The global asymptotic stability of the system is guaranteed, and the effectiveness of this novel framework is compared to benchmark studies. 相似文献
80.
Resilient cows are minimally affected in their functioning by infections and other disturbances, and recover quickly. Herd management is expected to have an effect on disturbances and the resilience of cows, and this effect was investigated in this study. Two resilience indicators were first recorded on individual cows. The effect of herd-year on these resilience indicators was then estimated and corrected for genetic and year-season effects. The 2 resilience indicators were the variance and the lag-1 autocorrelation of daily milk yield deviations from an expected lactation curve. Low variance and autocorrelation indicate that a cow does not fluctuate much around her expected milk yield and is, thus, subject to few disturbances, or little affected by disturbances (resilient). The herd-year estimates of the resilience indicators were estimated for 9,917 herd-year classes based on records of 227,655 primiparous cows from 2,644 herds. The herd-year estimates of the resilience indicators were then related to herd performance variables. Large differences in the herd-year estimates of the 2 resilience indicators (variance and autocorrelation) were observed between herd-years, indicating an effect of management on these traits. Furthermore, herd-year classes with a high variance tended to have a high proportion of cows with a rumen acidosis indication (r = 0.31), high SCS (r = 0.19), low fat content (r = ?0.18), long calving interval (r = 0.14), low survival to second lactation (r = ?0.13), large herd size (r = 0.12), low lactose content (r = ?0.12), and high production (r = 0.10). These correlations support that herds with high variance are not resilient. The correlation between the variance and the proportion of cows with a rumen acidosis indication suggests that feed management may have an important effect on the variance. Herd-year classes with a high autocorrelation tended to have a high proportion of cows with a ketosis indication (r = 0.14) and a high production (r = 0.13), but a low somatic cell score (r = ?0.17) and a low proportion of cows with a rumen acidosis indication (r = ?0.12). These correlations suggest that high autocorrelation at herd level indicates either good or poor resilience, and is thus a poor resilience indicator. However, the combination of a high variance and a high autocorrelation is expected to indicate many fluctuations with slow recovery. In conclusion, herd management, in particular feed management, seems to affect herd resilience. 相似文献