Cooperative medium access control based on spectrum leasing

Based on cooperative spectrum leasing, a distributed “win–win” (WW) cooperative framework is designed to encourage the licensed source node (SN) to lease some part of its spectral resources to the unlicensed relay node (RN) for the sake of simultaneously improving the SN’s achievable rate and for reducing the energy consumption (EC). The potential candidate RNs carry out autonomous decisions concerning whether to contend for a cooperative transmission opportunity, which could dissipate some of their battery power, while conveying their traffic in light of their individual service requirements. Furthermore, a WW cooperative medium-access-control (MAC) protocol is designed to implement the proposed distributed WW cooperative framework. Simulation results demonstrate that our WW cooperative MAC protocol is capable of providing both substantial rate improvements and considerable energy savings for the cooperative spectrum leasing system

A Strategy to Improve the Health of the Ciba Church According to Principles of Natural Church Development in the Context of the Seventh-day Adventist Denomination and Culture

Problem. Adventist churches in China do not operate under a denominational structure. As the government continues to open more churches, an increasing number of people become Adventists every day. Because of the fast growing pace of many churches in the past three decades, not much attention has been given to the health and quality aspect of church life. Therefore, the question of how to help the church to grow and to become healthy has become an urgent matter. Purpose. The purpose of this project is to develop and implement a strategy to improve the health of the Ciba Seventh-day Adventist Church in Southwest China by applying Christian Schwarz’s Natural Church Development (NCD) principles in the context of Chinese Seventh-day Adventism and the local culture. Method. The methodology was to use NCD to profile the Ciba church in southwest China and to identify its minimum factor, the lowest score among the eight quality characteristics of NCD. Attention would be given to the special context of the Chinese Adventist Church and Chinese culture in regard to NCD principles. One year after Ciba has worked on its minimum factor, a second profile would be done to compare with the first, and the result would be documented in this project. Result. Holistic Small Groups was found to be the minimum factor as the result of the first profile. Strategies were developed to increase this quality characteristic. However, the result of the second church profile showed little improvement of the minimum factor. Conclusions. Looking back at the results of the two church profiles and development and implementation of the strategies, it is still too early to tell if NCD principles can be useful in China. But I do believe NCD is a good measuring tool to help the Ciba church to identify its weaknesses. The potential that this experience may have a bigger impact in China lies in the fact that the Ciba church members were willing to put themselves to the test. As they share what they learned with Adventists in other parts of China, the possibility of raising awareness of the importance of a healthy church is very promising

Weak Measurement of Qubit Oscillations with Strong Response Detectors: Violation of the Fundamental Bound Imposed on Linear Detectors

We investigate the continuous weak measurement of a solid-state qubit by single electron transistors in nonlinear response regime. It is found that the signal-to-noise ratio can violate the universal upper bound imposed quantum mechanically to any linear response detectors. We understand the violation by means of the cross-correlation of the detector currents.Comment: 4 pages, 4 figure

Design and Evaluation of Digital Baseband Converter Sub-channel Delay Compensation Method on Bandwidth Synthesis

The effect of sub-channel delay on bandwidth synthesis is investigated to eliminate the “phase step” phenomenon in bandwidth synthesis during the test of CDBE (Chinese Digital Backend). Through formula derivation, we realize that sub-channel delay may cause phase discontinuity between different sub-channels. Theoretical analysis shows that sub-channel delay can induce bandwidth synthesis error in group delay measurement of the linear system. Furthermore, in the differential delay measurement between two stations, bandwidth synthesis error may occur when the LO (Local Oscillator) frequency differences of corresponding sub-channels are not identical. Error-free conditions are discussed under different applications. The phase errors among different sub-channels can be removed manually. However, the most effective way is the compensation of sub-channel delay. A sub-channel delay calculation method based on Modelsim is proposed. The compensation method is detailed. Simulation and field experiments are presented to verify our approach

Optimal Timing to Trade Along a Randomized Brownian Bridge

This paper studies an optimal trading problem that incorporates the trader's market view on the terminal asset price distribution and uninformative noise embedded in the asset price dynamics. We model the underlying asset price evolution by an exponential randomized Brownian bridge (rBb) and consider various prior distributions for the random endpoint. We solve for the optimal strategies to sell a stock, call, or put, and analyze the associated delayed liquidation premia. We solve for the optimal trading strategies numerically and compare them across different prior beliefs. Among our results, we find that disconnected continuation/exercise regions arise when the trader prescribe a two-point discrete distribution and double exponential distribution.Comment: 25 page