In cloud computing,fairness is one of the most significant indicators to evaluate resource allocation algorithms,which reveals whether each user is allocated as much as that of all other users having the same bottlene...In cloud computing,fairness is one of the most significant indicators to evaluate resource allocation algorithms,which reveals whether each user is allocated as much as that of all other users having the same bottleneck.However,how fair an allocation algorithm is remains an urgent issue.In this paper,we propose Dynamic Evaluation Framework for Fairness(DEFF),a framework to evaluate the fairness of an resource allocation algorithm.In our framework,two sub-models,Dynamic Demand Model(DDM) and Dynamic Node Model(DNM),are proposed to describe the dynamic characteristics of resource demand and the computing node number under cloud computing environment.Combining Fairness on Dominant Shares and the two sub-models above,we finally obtain DEFF.In our experiment,we adopt several typical resource allocation algorithms to prove the effectiveness on fairness evaluation by using the DEFF framework.展开更多
Organic spin valve (OSV), one of the most promising and representative devices involving spin injection, transport and detection, has drawn tremendous attention owing to their ultra-long spin relaxation time in the fi...Organic spin valve (OSV), one of the most promising and representative devices involving spin injection, transport and detection, has drawn tremendous attention owing to their ultra-long spin relaxation time in the field of molecular spintronics. Since the first demonstration of truly worked vertical OSV device in 2004, efforts in enhancement of high performance and pursuit of spin-related nature have been devoted in related field. It offers a new opportunity to develop the integrated flexible multi-functional arrays based on spintronics in the future. However, the unreliable working state in OSVs due to the lack of exploration on interface control will cause severe impact on the performance evaluation and further restrict their practical application. Herein, we focus on the recent progress in strategies for reliable fabrication and evaluation of typical OSVs in vertical configuration. Firstly, the challenges in protection of two spin interface properties and identification of spin-valve-like signals were proposed. Then, three points for attention including selection of bottom electrodes, optimization of organic spacer, and prevention of metal penetration to improve the device performance and reliability were mentioned. Particularly, various modified strategies to solve the “dead layer” issue were highlighted. Furthermore, we discussed the general protocols in the reliable evaluation of OSVs’ performance and transport mechanism identification. Notably, several key fundamentals resulting in spurious magnetoresistance (MR) response were illustrated. Finally, we also highlighted the future perspectives on spintronic devices of organic materials.展开更多
基金supported in part by Program for Changjiang Scholars and Innovative Research Team in University No.IRT1078The Key Program of NSFC-Guangdong Union Foundation No.U1135002The Fundamental Research Funds for the Central Universities No.JY0900120301
文摘In cloud computing,fairness is one of the most significant indicators to evaluate resource allocation algorithms,which reveals whether each user is allocated as much as that of all other users having the same bottleneck.However,how fair an allocation algorithm is remains an urgent issue.In this paper,we propose Dynamic Evaluation Framework for Fairness(DEFF),a framework to evaluate the fairness of an resource allocation algorithm.In our framework,two sub-models,Dynamic Demand Model(DDM) and Dynamic Node Model(DNM),are proposed to describe the dynamic characteristics of resource demand and the computing node number under cloud computing environment.Combining Fairness on Dominant Shares and the two sub-models above,we finally obtain DEFF.In our experiment,we adopt several typical resource allocation algorithms to prove the effectiveness on fairness evaluation by using the DEFF framework.
基金The authors acknowledge financial support from the National Key R&D Program of China (Nos. 2016YFB0401100 and 2017YFA0204503)the National Natural Science Foundation of China (Nos. 52003190, 51633006, 91833306, 21875158, 51703159, and 51733004).
文摘Organic spin valve (OSV), one of the most promising and representative devices involving spin injection, transport and detection, has drawn tremendous attention owing to their ultra-long spin relaxation time in the field of molecular spintronics. Since the first demonstration of truly worked vertical OSV device in 2004, efforts in enhancement of high performance and pursuit of spin-related nature have been devoted in related field. It offers a new opportunity to develop the integrated flexible multi-functional arrays based on spintronics in the future. However, the unreliable working state in OSVs due to the lack of exploration on interface control will cause severe impact on the performance evaluation and further restrict their practical application. Herein, we focus on the recent progress in strategies for reliable fabrication and evaluation of typical OSVs in vertical configuration. Firstly, the challenges in protection of two spin interface properties and identification of spin-valve-like signals were proposed. Then, three points for attention including selection of bottom electrodes, optimization of organic spacer, and prevention of metal penetration to improve the device performance and reliability were mentioned. Particularly, various modified strategies to solve the “dead layer” issue were highlighted. Furthermore, we discussed the general protocols in the reliable evaluation of OSVs’ performance and transport mechanism identification. Notably, several key fundamentals resulting in spurious magnetoresistance (MR) response were illustrated. Finally, we also highlighted the future perspectives on spintronic devices of organic materials.
