Differential power analysis (DPA) is an effective side channel attack method, which poses a critical threat to cryptographic algorithms, especially lightweight ciphers such as SIMON. In this paper, we propose an area-efficient countermeasure against DPA on SIMON based on the power randomization. Firstly, we review and analyze the architecture of SIMON algorithm. Secondly, we prove the threat of DPA attack to SIMON by launching actual DPA attack on SIMON 32/64 circuit. Thirdly, a low-cost power randomization scheme is proposed by combining fault injection with double rate technology, and the corresponding circuit design is implemented. To the best of our knowledge, this is the first scheme that applies the combination of fault injection and double rate technology to the DPA-resistance. Finally, the t-test is used to evaluate the security mechanism of the proposed designs with leakage quantification. Our experimental results show that the proposed design implements DPA-resistance of SIMON algorithm at certain overhead the cost of 47.7% LUTs utilization and 39.6% registers consumption. As compared to threshold implementation and bool mask, the proposed scheme has greater advantages in resource consumption.

To analyze the influence of tradable credits and bus departure quantity on travelers' travel mode choice, this study investigated car travel and bus travel as research objects and established a two-mode day-to-day travel mode choice model based on tradable credits and bus departure quantity. To improve the guiding effect of tradable credits and bus departure quantity, an optimization scheme of tradable credits and bus departure quantity was developed with the goal of minimizing the system total travel time of car travel and the system total comprehensive cost of bus travel. Taking a test transportation network as an example, the influence of no tradable credits scheme, tradable credits scheme, and tradable credits and bus departure quantity scheme on the travelers’ travel mode choice behavior was analyzed. The results showed that the tradable credits and bus departure quantity scheme could reduce the saturation of road traffic and improve bus service quality.

In order to address the water contamination and supply problems in China, a number of water pricing policies have been introduced. They include water resource fees, water supply charges, wastewater treatment fees, and water pollution levies. The purposes of China’s water pricing policies are to protect and conserve water resources, encourage reasonable utilization of water resources, control pollution, and protect the environment. However, concern about the affordability of China’s water pricing for users has resulted in generally low tariffs. Moreover, as a result of poor supervision, China’s actual revenues from water pricing are far less than receivables. Consequently, wastewater discharges still produce pollution, while the polluters achieve environmental dividends by bearing relatively low pollution control costs. China’s water pricing policies should be improved through application of the polluter-pays principle and full-cost pricing. It is also necessary to strengthen environmental laws by specifying environmental standards on the basis of environmental non-degradation.

With the rapid development of urbanization in China, many cities begin to build subway to relieve the increasing traffic pressure. How to evaluate effect of subway on existing urban traffic system interests urban planners. Space Syntax is the most widely used theory for calculating accessibility measures. However, as the basis model of space syntax, axial-map is only aimed at 2D traffic system, not suitable for 3D situation. Based on natural-street map, a method is proposed which treats stations as junctions between subway and streets and rebuilds relation matrix to calculate accessibility. Using the method, we analyze a case study of Xi’an city in china. It is found out that subway can change accessibility to some extent depended on routine of subway and site of station, which implies it reasonable to layout subway along streets with high integration.