Detecting Extra Dimension by Helium-like Ions

Considering that gravitational force might deviate from Newton's inverse-square law and become much stronger in small scale, we present a method to detect the possible existence of extra dimensions in the ADD model. By making use of an effective variational wave function, we obtain the nonrelativistic ground energy of a helium atom and its isoelectronic sequence. Based on these results, we calculate gravity correction of the ADD model. Our calculation may provide a rough estimation about the magnitude of the corresponding frequencies which could be measured in later experiments.Comment: 8 pages, no figures, accepted by Mod. Phys. Lett.

2D-TCAD Simulation on Retention Time of Z2FET for DRAM Application

Traditional memory devices are facing more challenges due to continuous down-scaling. 6T-SRAM suffers from variability [1-2] and reliability [3-4] issues, which introduce cell stability problems. DRAM cells with one transistor, one capacitor (1T1C) struggle to maintain refresh time [5-6]. Efforts have been made to find new memory solutions, such as one transistor (1T) solutions [7-9]. Floating body based memory structures are among the potential candidates, but impact ionization or band-to-band tunnelling (B2BT) limits their refresh time [10]. A recently proposed zero impact ionization and zero subthreshold swing device named Z2FET [9, 11-12] has been demonstrated and is a promising candidate for 1T DRAM memory cell due to technology advantages such as CMOS technology compatibility, novel capacitor-less structure and sharp switching characteristics. In the Z2FET memory operation, refresh frequency is determined by data retention time. Previous research [11-12] is lacking systematic simulation analysis and understanding on the underlying mechanisms. In this paper, we propose a new simulation methodology to accurately extract retention time in Z2FET devices and understand its dependency on applied biases, temperatures and relevant physical mechanisms. Since the stored ‘1’ state in Z2FET is an equilibrium state [9, 11-12] and there is no need to refresh, we will concentrate on state ‘0’ retention. Two types of ‘0’ retention time: HOLD ‘0’ and READ ‘0’ retention time will be discussed separately

Review of Transmission Fixed Costs Allocation Methods

In the context of competitive electricity markets, transmission fixed costs should be fairly allocated to transmission users. A reasonable allocation method could lead to efficient utilizations of existing transmission facilities and, at the same time, provide economic signals for guiding future generation planning and load sitting. In this paper, a comprehensive literature survey is made on available methods of transmission fixed cost allocations. The review is conducted from several different aspects including: costs to be allocated, entities to pay the costs, system states to be based on, cost allocations of unused capacities, pricing of counter flow and that of reactive power, and allocation principles and methods. In addition, the characteristics of each method are analyzed and compared with those of the others.published_or_final_versio

The concept and algorithm of 'conductor renting' and its application in transmission losses allocation

The cost of transmission losses represents an important part of transmission costs. In the context of competitive electricity marketplace, the costs caused by transmission losses should be reasonably allocated to various market participants, but the nonlinearity of the transmission losses function makes the allocation very difficult. In this paper, the concept of 'conductor renting' is proposed for the first time and is used to solve transmission losses allocation problem. The analysis indicates that the active power losses caused by different current components are in proportion to the conductor section acreage and the corresponding conductance used by the current components, and the reactive power losses caused by current components have similar characteristics. Based on the concept of conductor renting, it is easy to solve the losses allocation problem, and the interaction effect of the transactions is eliminated.published_or_final_versio