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The primary way to design building structures refers to the stationary loads specified by the governing laws. However, the load pattern does not guarantee the appropriateness of the seismic design. To make matters worse, old or ancient structures are traditionally reinforced for gravitational loads. This study reveals that the traditional reinforcement, in most cases, harms the seismic performance of buildings. The authors introduced the approach of most computer programs for seismic design, along with their limitations. Then, the ancient Roman approach was explained, and the reasons for the survival of many of these ancient structures were exposed thoroughly. After that, classical advices were summarized briefly for good seismic design of structures and reinforcement. Finally, a few classical mistakes were identified in reinforcement design.

This study aims to realize continuous, high efficiency defrosting of air-to-air heat pumps using the effect of outdoor warm air recycling, trying to improve the coefficient of performance (COP) and total heat capacity of traditional defrosting methods like hot bypass and Joule heating. The proposed patented method recovers heat from the air change system by mixing the warm discarded air with the incoming air of the external heat exchanger. The fan of the external unit sucks the indoor air with the depression obtained by a Venturi. The warm air is ducted to the Venturi through a hole in the wall. The amount of warm air mixed to the outside air is regulated by a butterfly valve installed on the pipe from the hole to the Venturi. In this way, the air entering the external coil is warm enough to avoid frost. The energy efficiency of the system is assured, for the warm indoor air is heated with the high COP of the heat pump. Our system can achieve defrosting with a limited amount of warm air, and realize a higher overall COP than the best traditional defrosting systems. Finally, the defrosting device can be added as an option to any existing split systems.