scholarly journals On the Classical Capacity of General Quantum Gaussian Measurement

Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 377
Author(s):  
Alexander Holevo
Keyword(s):  
Dual Problem ◽  
Measurement Channel ◽  
Gaussian Channel ◽  
Quantum Communications ◽  
Classical Capacity ◽  
Optimal Ensemble ◽  
Accessible Information ◽  
Measurement Channels ◽  
Gaussian Ensemble ◽  
Average State

In this paper, we consider the classical capacity problem for Gaussian measurement channels. We establish Gaussianity of the average state of the optimal ensemble in the general case and discuss the Hypothesis of Gaussian Maximizers concerning the structure of the ensemble. Then, we consider the case of one mode in detail, including the dual problem of accessible information of a Gaussian ensemble. Our findings are relevant to practical situations in quantum communications where the receiver is Gaussian (say, a general-dyne detection) and concatenation of the Gaussian channel and the receiver can be considered as one Gaussian measurement channel. Our efforts in this and preceding papers are then aimed at establishing full Gaussianity of the optimal ensemble (usually taken as an assumption) in such schemes.

On Analogue TMR System

2011 ◽  
pp. 30-46
Author(s):  
Pavel Kucera
Keyword(s):  
Markov Processes ◽  
Measurement Channel ◽  
Reliability Model ◽  
Channel System ◽  
Triple Modular Redundancy ◽  
Reliability Modelling ◽  
Measurement Channels ◽  
Modular Redundancy ◽  
Digital Channels ◽  
Wiring System

This chapter presents a reliability model of the TMR (Triple Modular Redundancy) system based on analogue measurement channels. While reliability modelling of the standard TMR system (based on digital channels) has been well described in many previous publications, an applicable reliability solution for analogue measurement channels is still missing. First, the structure of analogue measurement channel is described in this chapter. Then, the reliability model of the wiring system is introduced. Next, the standard TMR model is presented and its reliability model is mentioned. An analogue TMR measurement channel system is introduced and its reliability model based on Markov processes is presented. Then the reliability model of the communication channel is described. Finally, the reliability of this model is analytically calculated and the solution is applied to an example.

Separable states can be used to realize the fair quantum communication

2019 ◽  
Vol 17 (01) ◽  
pp. 1950004
Author(s):  
Dong-Mei Gao ◽  
Ying Xin ◽  
Zai-Liang Ye ◽  
Xiao-Yan Qiao
Keyword(s):  
Channel Coding ◽  
Quantum Communication ◽  
Sufficient Conditions ◽  
Basic Question ◽  
Classical Correlation ◽  
Quantum Communications ◽  
Nonclassical State ◽  
Accessible Information ◽  
Essential Resource ◽  
Classical Means

When Alice and Bob are never entangled with each other, can they share equal amount of information via noiseless channels? When the transfered subsystem B is classical, this basic question concerning communication capacity has a very satisfying answer: the amount of accessible information, as quantified by the classical correlation on B, is always equal. If the subsystem B is in a nonclassical state, the amount of accessible information, like their classical counterparts, is also well quantified by classical correlation, but the similarity ends here: the amount of accessible information from shared states may not be equal, because the subsystem B cannot be accessed perfectly by classical means. In this work, we show how to establish fair quantum communications. Our results give sufficient conditions for fair quantum communications and show that symmetric discord is the essential resource for this task. We further demonstrate that the fair quantum communication is fundamentally the same as the Shannon noisy channel coding theorem.

On Analogue TMR System

2012 ◽  
Vol 3 (4) ◽  
pp. 1-18
Author(s):  
Pavel Kucera
Keyword(s):  
Communication Channel ◽  
Measurement Channel ◽  
Reliability Model ◽  
Channel System ◽  
Triple Modular Redundancy ◽  
Reliability Modelling ◽  
Measurement Channels ◽  
Modular Redundancy ◽  
Digital Channels ◽  
Wiring System

This chapter presents a reliability model of the TMR (Triple Modular Redundancy) system based on analogue measurement channels. While reliability modelling of the standard TMR system (based on digital channels) has been well described in many previous publications, an applicable reliability solution for analogue measurement channels is still missing. First, the structure of analogue measurement channel is described in this chapter. Then, the reliability model of the wiring system is introduced. Next, the standard TMR model is presented and its reliability model is mentioned. An analogue TMR measurement channel system is introduced and its reliability model based on Markov processes is presented. Then the reliability model of the communication channel is described. Finally, the reliability of this model is analytically calculated and the solution is applied to an example.

scholarly journals INFORMATION TRANSMISSION VIA ENTANGLED QUANTUM STATES IN GAUSSIAN CHANNELS WITH MEMORY

2006 ◽  
Vol 04 (03) ◽  
pp. 439-452 ◽  
Author(s):  
NICOLAS J. CERF ◽  
JULIEN CLAVAREAU ◽  
JÉRÉMIE ROLAND ◽  
CHIARA MACCHIAVELLO
Keyword(s):  
Quantum Channel ◽  
Quantum States ◽  
Gaussian Channel ◽  
Hard Problem ◽  
Quantum Channels ◽  
Classical Capacity ◽  
Gaussian Channels ◽  
Memoryless Channels ◽  
Entangled Quantum States ◽  
With Memory

Gaussian quantum channels have recently attracted a growing interest, since they may lead to a tractable approach to the generally hard problem of evaluating quantum channel capacities. However, the analysis performed so far has always been restricted to memoryless channels. Here, we consider the case of a bosonic Gaussian channel with memory, and show that the classical capacity can be significantly enhanced by employing entangled input symbols instead of product symbols.

Assessing impact of the provision of accessible information to families with Congenital Hyperinsulinism (CHI)

2016 ◽  
Author(s):  
Lauren Trimarco ◽  
Indi Banerjee ◽  
Lindsey Rigby ◽  
Louise Bowden ◽  
Maria Salomon Estebanez ◽  
...  
Keyword(s):  
Congenital Hyperinsulinism ◽  
Accessible Information

Comparison of Time spent between an electronic and a paper-based laboratory information system by laboratorians at a polyclinic in Greater Accra, Ghana: A time-motion study

2020 ◽  
Author(s):  
Philip Boakye
Keyword(s):  
Information System ◽  
Negative Impact ◽  
Laboratory Information System ◽  
Time Motion ◽  
Accessible Information ◽  
Motion Study ◽  
Significant Difference ◽  
Significant Negative Impact ◽  
Key Issues ◽  
Motion Studies

The acceptance of electronic laboratory information system (LIS) is gradually increasing in developing countries. However, the issue of time effectiveness due to computerization is less clear as there is fewer accessible information. One of the key issues for laboratorians is their indecision with LISs’ would-be effect of time on their work. A polyclinic in Ghana was in the process of implementing electronic LIS. Several of the laboratorians did not have knowledge and skill in computing and there were disagreeing views on the time effectiveness of the LIS after implementation. The management of the polyclinic laboratory was concerned to assess time advantageousness of recording data when using the electronic LIS compared with paper-based LIS. <div><br></div><div>Five randomly selected laboratorians were provided two sheets of paper with tables to document the time they spent for both paper-based and electronic LIS. Data were collected for a total of 230 records,115 electronic LIS and 115 paper-based LIS. The t-test (mean-comparison test) was computed to compare the means of both electronic and paperbased LIS times. </div><div><br></div><div>There was a statistical significant difference in the time spent between electronic and paper-based LIS. The time spent between paper-based and electronic LIS was 0.41 minutes (95% CI 0.15 to 0.66) longer than in electronic LIS. </div><div><br></div><div>LIS can be adopted in polyclinics without having significant negative impact on time spent between electronic and paper-based LIS. More time–motion studies that include laboratorians are however necessary in order to get a more complete picture of time spent between electronic and paper-based LIS. </div>

Transportation Economic and Land Use System

1998 ◽  
Vol 1617 (1) ◽  
pp. 84-89 ◽  
Author(s):  
Louis J. Pignataro ◽  
Joseph Wen ◽  
Robert Burchell ◽  
Michael L. Lahr ◽  
Ann Strauss-Wieder
Keyword(s):  
Land Use ◽  
Information System ◽  
Management Tool ◽  
Improvement Program ◽  
Transportation Projects ◽  
Accessible Information ◽  
Surface Transportation ◽  
Land Use System ◽  
Land Use Effects ◽  
Computer Based

The purpose of the Transportation Economic and Land Use System (TELUS) is to convert the transportation improvement program (TIP) into a management tool. Accordingly, the system provides detailed and easily accessible information on transportation projects in the region, as well as their interrelationships and impacts. By doing so, TELUS enables public-sector agencies to meet organizational, Intermodal Surface Transportation Efficiency Act, state, and other mandates more effectively. The objectives are accomplished by providing the computer-based capability to analyze, sort, combine, and track transportation projects in or under consideration for a TIP; assessing the interrelationships among significant transportation projects; estimating the regional economic and land use effects of transportation projects; and presenting project information in an easily understood format, including geographic information system formats.

The invisible hole of information on SMB's cybersecurity

2019 ◽  
Vol 7 (1) ◽  
pp. 14-26
Author(s):  
Ruti Gafni ◽  
Tal Pavel
Keyword(s):  
Mass Communication ◽  
Cyber Attacks ◽  
Communication Media ◽  
Specific Information ◽  
Exploratory Research ◽  
Cyber Attack ◽  
Public Attention ◽  
Cyber Threats ◽  
Accessible Information ◽  
Types Of Information

Small and Medium Businesses (SMB) use Internet and computer-based tools in their daily processes, sometimes without being aware to the cyber threats, or without knowing how to be prepared in case of a cyber-attack, although they are a major target for cyber-attacks. Specific information about cybersecurity needed by SMBs, in order to cope with cyber threats, is not always available or easily accessible. In this study, a vast search of different types of information about SMBs’ cybersecurity was performed, in order to find whether a hole of accessible information exists in this area. This exploratory research covered general mass communication media channels, technological and professional cybersecurity websites, and academic journals, and found that indeed very few studies, articles and news items were published in this matter. Leveraging knowledge and awareness, diminishing the shame for reporting cyber-attacks, and increasing mass communication media interest and public attention, may be activities to cover this “invisible hole”.

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