Key Capacity Research Articles

Secure Storage Capacity Under Rate Constraints—Continuity and Super Activation

The source model for secret key generation with one way public communication refers to a setting in which a secret key should be agreed upon at two terminals. At both terminals correlated components of a common source are available. In addition, a message can be sent from one terminal to the other via a public channel. In this paper, a related scenario is considered where instead of secret key generation, the goal is to securely store data in a public database. The database allows for error-free storing of the data, but is constrained in its size which imposes a rate constraint on storing. The corresponding capacity for secure storage is known and it has been shown that the capacity-achieving strategy satisfies the strong secrecy criterion. Here, the case when the storage in the public database is subject to errors is considered and the corresponding capacity is characterized. In addition, the continuity properties of the two capacity functions are analyzed. These capacity functions are continuous as opposed to the discontinuous secret key capacity with rate constraint. It is shown that for secure storage the phenomenon of super activation can occur. Finally, it is discussed how the results in this paper differ from previous results on super activation.

Feasibility of twin-field quantum key distribution based on multi-mode coherent phase-coded states.

In this paper we propose feasibility demonstration of twin-field quantum key ditribution system based on multi-mode weak coherent phase-coded states. Their utilization provides indisputable advantages described in the paper. We also provide the detailed description of nontrivial interference scheme for those states and derive detection and quantum bit error rates. Since we propose the feasibility scheme we present in this paper only asymptotic secure key estimation and show that in principle it can beat well-known fundamental limit of repeaterless quantum communications , i.e., the secret key capacity of the lossy communication channel. Also we present here the experimental setup and provide the experimental values of detection rates dependence on the modulation signals phase difference.

Quantification of human vulnerability to earthquake-induced landslides using Bayesian network

Devastating landslides were frequently triggered by earthquakes and caused severe damage and human losses. More than 25,000 people were killed by the Wenchuan earthquake-induced landslides. A proper model for estimating loss of lives is important in quantifying the human risks posed by earthquake-induced landslides. This paper presents a new model for quantitatively estimating the human vulnerability to earthquake-induced landslides using Bayesian networks. A database incorporating information of fatal landslides induced by the Wenchuan earthquake is established. A Bayesian network is constructed according to a logic structure of loss-of-life mechanisms by considering four types of key factors, i.e., deposit thickness, building damage, evacuation, and resistance capacity. The probabilities of the nodes (factors) and the arcs (inter-relationships) of the network are quantified according to statistical data, judgment based on experiences, and existing physical or empirical models. The human vulnerability to earthquake-induced landslides is quantitatively estimated through constructing a systematic structure considering the uncertainties of the control factors and their inter-relationships. Comparison between the recorded fatality rate and predicted fatality is conducted to verify the proposed model. Finally, sensitivity analysis is conducted to identify the most important parameters that lead to loss of lives.

Image Analysis Using Deep Learning Techniques

In late years, critical learning methodologies especially Convolutional Neural Networks have been utilized in different solicitations. CNN's have appeared to be a key capacity to ordinarily expel broad volumes of data from massive information. The uses of CNNs have inside and out ended up being useful especially in orchestrating ordinary pictures. Regardless, there have been essential obstacles in executing the CNNs in a restorative zone as a result of the nonattendance of genuine getting ready data. Consequently, general imaging benchmarks, for instance, Image Net have been conspicuously used in the restorative not too zone notwithstanding the way that they are perfect when appeared differently about the CNNs. In this paper, a comparative examination of LeNet, AlexNet, and GoogLeNet has been done. Starting there, the paper has proposed an improved hypothetical structure for requesting helpful life structures pictures using CNNs. In perspective on the proposed structure of the framework, the CNNs building are required to beat the previous three plans in requesting remedial pictures.

Foreign direct investment and economic growth nexus in Africa

PurposeAfrican countries are generally fragile. This and other related characteristics affect the potential for growth and development. The purpose of this paper is to investigate whether the effect of FDI on economic growth is contingent on a financial system that accounts for financial market fragility. An important point of departure from earlier studies is the adoption of a new measure of financial market fragility.Design/methodology/approachGiven the uniqueness of the data set, the study uses a panel data and estimates an econometric model using an instrumental variable approach. For robustness purposes, a pooled ordinary least square is also estimated.FindingsThe study provides evidence that if the financial market is fragile as in the case of Africa, FDI inflows may have a marginally significant positive impact on economic growth. The findings suggest that fragility in the financial market is a key absorptive capacity and cannot be trivialised when exploring FDI–growth nexus in Africa.Research limitations/implicationsThe uniqueness of the data set limited the time period of the study. Nonetheless, the findings are still crucial to policy makers in Africa and other developing countries with similar characteristics.Originality/valueTo the best of the authors’ knowledge, this is the first study in Africa to investigate the FDI–growth nexus which accounts for financial market fragility.

Round table: Strengthening capacities in health information for better public health practice in Member States

Abstract According to Sir Michael Marmot: “To address inequalities in health in Europe, our first step must be to address the inequalities in health information (HI). All too commonly where health is poorest, HI tends to be poorest. HI is absent or incomplete just where we need it most.” One of the specific objectives of the Joint Action on Health Information (InfAct) is to reduce HI inequalities between and within EU Member States (MS). InfAct is addressing this through various capacity strengthening exercises including the design of a sustainable EU HI training programme. In this workshop, a first presentation will describe the development of the HI training programme for professionals working in HI within MS institutions. Subsequently, four capacity strengthening exercise will be presented illustrating potential topics to be covered in such a sustainable HI training programme. These 5 short presentations will feed the discussion of the workshop organised as a round table. The first exercise is an assessment of HI systems carried out by InfAct through peer review in 9 countries using an adjusted WHO Europe tool. The exercise builds on the framework of mutual learning and good practice exchange to identify in a standardised way strengths and limitations, and recommendations for direct and long-term improvement of their HI system. The second exercise presents 2 workshops given by InfAct on the European and National Burden of Disease (BoD) methodologies. The effort contributed to harmonising BoD methodologies at national and EU levels, thereby increasing comparability and facilitating knowledge exchange on BoD bilaterally and multilaterally in the EU. The third exercise presents an example of capacity building activities organised in the framework of a national prevention programme on cardiovascular risk assessment, which includes training of health professionals, provision of training material and risk evaluation tools, implementation in clinical practice, health data collection, and feedback of results in the community. The fourth exercise presents examples of capacity building activities by the European Health Examination Survey (EHES) initiative to establish a sustainable European network on nationally representative Health Examination Surveys (HESs), through hands-on training events, online training materials, person-to-person consultations, site visits and networking. This workshop provides participants insights on current activities in HI capacity strengthening in Europe which address health (information) inequalities. Additionally, participants will be able to provide feedback on the development of the sustainable HI training programme and potential elements that could be included based on four practical examples. The participants will be able to highlight their needs in health information training by interacting through a round table panel discussion. Key messages Health information capacity strengthening is essential to address health inequalities. The workshop identifies what a sustainable EU HI training program can provide. Mutual learning, knowledge and good practice exchange can be organised in various ways – we show practical current examples on how it has been done.

Skills building seminar: Building skills and capacity for a future health workforce

Abstract Background It is increasingly recognised that there is ‘no health without a workforce’ and that action has to be taken to develop an integrated and sustainable future health workforce. However, training and education opportunities are lacking for all those engaged in health workforce development. There is an urgent need for health systems and policy to foster skills building and institutional capacity for health workforce development to respond effectively to changing healthcare needs of the population and to the labour market shortages in many countries. Objectives This seminar will address these issues and help reducing the knowledge gaps. The seminar is arranged around for major topics: the WHO framework for action to guide health workforce planning and governance, the competences framework to strengthen the education and professionalisation of public health developed by the WHO Coalition of Partners and ASPHER, the internationalisation of health professional education using medical education in Romania as a case study, and finally a framework for strengthening health workforce research. The seminar aims to help PhD students and early career researchers to develop skills in the field of health workforce research and development. It also provides knowledge and tools for policymakers and practitioners who are responsible for health workforce education and governance. This seminar will promote the development of training programmes for health workforce research and thereby contribute to public health leadership in health workforce development. There will be ample time for discussion and teaching material will be made available for the participants. Key messages Building skills and institutional capacity is key to improve health workforce research and policy. People-centred care and universal healthcare coverage call for new skills and education programmes.

Roma health mediators in Serbia – good example of multisectoral cooperation in health promotion

Abstract Issue Within the framework of the JA CHRODIS plus participants of the WP5 worked on identification of factors that contribute to collaboration within healthcare and between the broader health system and other sectors, as well as their enablers and barriers. In Serbia, practice that was identified and elaborated was aimed at improvement of health of Roma population. Description of the problem Based on available data, health indicators among Roma population in Serbia were two to three times worse than national averages. In order to tackle this issue, government of the Republic of Serbia, started with implementation of the project of education and inclusion of Roma health mediators in the health system. This project has been implemented in Serbia since 2009. Roma Health mediators (Roma ethical minority females) were trained for fast and efficient provision of support to Roma families. Results As a result of the project there was increased number of visits to health institutions and preventive check-ups of target population. Established cooperation between Roma health mediators and other health professionals in centers for primary health care, social care, and local self-government helped them in fulfilling their tasks, but also built capacity of other service providers to work in Roma communities. Through trainings they increase knowledge on various health, social and child care topics. Lessons Capacity building and inclusion of memebrs of vulnerable population into health promotion of the own to this population in terms of better acceptance of specific population population is useful to access groups as they can better understand and adapt to the needs of groups they want to reach. They should have opportunity to share their experience and lessons learned with experts involved in planning interventions for other vulberable groups. Key messages Building capacity of Roma mediators empowers them for integration into society beyond the scope of the Project. Lessons learned should be used for planning further actions for vulnerable groups.

Sustainable Development Goals and the challenge of Human resources for health in Congo

Abstract Background In order to achieve the Sustainable Development Goals (SDGs), equitable access to skilled and motivated health workers within a performing health system is need to be ensured. The health system in Congo is characterized by low quantity and quality of Human resources for health (HRH), which constitutes an important barrier to achieving to expanding coverage and integrated primary health care. Objectives To estimate needs of HRH in Congo from 2019 to 2030 and analysed the capacity of the country to address the estimated needs. Methods Cross-sectional study was conducted in Ministry of Health from June to November 2018. Data from 2011 national HRH Census was used as the baseline for projections. We performed annual projections based on current numbers of midwives, nurses and physicians. Health workforce-population ratios by year in national and department level were provided. Population estimations were computed using Spectrum software assuming a 3% growth rate. Mapping for distribution by department was performed used QSGI software. Results In 2019, Congo has 4849 midwives, nurses and physicians, including 465 doctors, 912 midwives and 3469 nurses. All of Congo departments have not surpassed the availability threshold of 4, 5 midwives, nurses and physicians per 1000 inhabitants in 2019. In overall, this ratio will rise from 0.9 per 1000 inhabitants in 2019 to 0.42 per 1000 inhabitants in 2030 due to the retirement. Needs for additional workforce were estimated at 29416 midwives, nurses and physicians by 2030, average of 2451 per year. However, current national production capacity of human resources for health is very low and will not cover the estimated needs as scheduled. Conclusions There is a crisis in the health workforce in Congo, expressed in acute shortage. Results highlight needs of building adequate policies to address production and management of the health workforce, to come close to reaching the MDGs for health. Key messages At current production capacity, Congo has not the number of physicians, nurses, and midwives it needs to address HRH shortages in the national Health system by 2030. The health human resources crisis in sub-Saharan Africa countries will be a major obstacle to achieving the Millennium Development Goals.

Covert Secret Key Generation With an Active Warden

We investigate the problem of covert and secret key generation over a state-dependent discrete memoryless channel with one-way public discussion in which an adversary, the warden, may arbitrarily choose the channel state. We develop an adaptive protocol that, under conditions that we explicitly specify, not only allows the transmitter and the legitimate receiver to exchange a secret key but also conceals from the active warden whether the protocol is being run. When specialized to passive adversaries that do not control the channel state, we partially characterize the covert secret key capacity. In particular, the covert secret key capacity is sometimes equal to the covert capacity of the channel, so that secrecy comes "for free."

Improving consistency among models of overlapping scope in multi-sector studies: The case of electricity capacity expansion scenarios

Multi-decadal scenarios produced by modeling studies are used to study the evolution of key infrastructure that cuts across energy, water, and land systems. Scenarios produced by different models contain inconsistencies due to disparate model structures and assumptions. Although inconsistencies can characterize structural uncertainties, they could have important consequences in various contexts such as multi-sector energy-water-land studies that couple multiple models. In such studies, it is important for models with overlapping scope (models having different sectoral, regional, temporal, and process details but producing scenarios for some common output variable(s)) to produce consistent scenarios of common output variable(s) to minimize propagation of inconsistent information. Using the example of baseline electricity capacity expansion scenarios produced by two models with overlapping scope, we explore cross-model scenario consistency (extent to which projections for a common scenario variable(s) diverge). We define a quantitative metric of consistency and examine the sensitivity of consistency of the models’ electricity generation by technology outputs to changes in harmonization of assumptions surrounding the representations of key capacity expansion drivers such as fuel prices, renewable resources, demand, and retirements. Our study establishes a framework to systematically examine scenario consistency. In addition, our study utilizes complementary features of well-established models to produce consistent baseline electricity capacity expansion scenarios which can then be used in multi-sector studies.

Tight bounds for private communication over bosonic Gaussian channels based on teleportation simulation with optimal finite resources

Upper bounds for private communication over quantum channels can be derived by adopting channel simulation, protocol stretching, and relative entropy of entanglement. All these ingredients have led to single-letter upper bounds to the secret key capacity which can be directly computed over suitable resource states. For bosonic Gaussian channels, the tightest upper bounds have been derived by employing teleportation simulation over asymptotic resource states, namely the asymptotic Choi matrices of these channels. In this work, we adopt a different approach. We show that teleporting over an analytical class of finite-energy resource states allows us to closely approximate the ultimate bounds for increasing energy, so as to provide increasingly tight upper bounds to the secret-key capacity of one-mode phase-insensitive Gaussian channels. We then show that an optimization over the same class of resource states can be used to bound the maximum secret key rates that are achievable in a finite number of channel uses.

Brain regulation of emotional conflict predicts antidepressant treatment response for depression.

The efficacy of antidepressant treatment for depression is controversial due to only modest superiority demonstrated over placebo. However, neurobiological heterogeneity within depression may limit overall antidepressant efficacy. We sought to identify a neurobiological phenotype responsive to antidepressant treatment by testing pretreatment brain activation during response to, and regulation of, emotional conflict as a moderator of the clinical benefit of the antidepressant sertraline versus placebo. Using neuroimaging data from a large randomized controlled trial, we found widespread moderation of clinical benefits by brain activity during regulation of emotional conflict, in which greater down-regulation of conflict-responsive regions predicted better sertraline outcomes. Treatment-predictive machine learning utilizing brain metrics outperformed a model trained on clinical and demographic variables. Our findings demonstrate antidepressant response is predicted by brain activity underlying a key self-regulatory emotional capacity. Leveraging brain-based measures in psychiatry will forge a path toward better treatment personalization, refined mechanistic insights, and improved outcomes.Trial RegistrationEstablishing Moderators and Biosignatures of Antidepressant Response for Clinical Care for Depression (EMBARC),

Experimental Twin-Field Quantum Key Distribution through Sending or Not Sending.

Channel loss seems to be the most severe limitation on the practical application of long distance quantum key distribution. The idea of twin-field quantum key distribution can improve the key rate from the linear scale of channel loss in the traditional decoy-state method to the square root scale of the channel transmittance. However, the technical demands are rather tough because they require single photon level interference of two remote independent lasers. Here, we adopt the technology developed in the frequency and time transfer to lock two independent laser wavelengths and utilize additional phase reference light to estimate and compensate the fiber fluctuation. Further, with a single photon detector with a high detection rate, we demonstrate twin field quantum key distribution through the sending-or-not-sending protocol with a realistic phase drift over 300km optical fiber spools. We calculate the secure key rates with the finite size effect. The secure key rate at 300km (1.96×10^{-6}) is higher than that of the repeaterless secret key capacity (8.64×10^{-7}).

On the Algorithmic Computability of the Secret Key and Authentication Capacity Under Channel, Storage, and Privacy Leakage Constraints

Secret key generation refers to the problem of generating a common secret key without revealing any information about it to an eavesdropper. All users observe correlated components of a common source and can further use a noisy public channel for discussion, which is open to eavesdroppers. A related problem is that of secure authentication, which has structural similarities and connections to the first problem. For authentication, users need to be enrolled and securely authenticated while minimizing the privacy leakage rate. This paper studies the algorithmic computability of the forward secret key capacity and the secure authentication capacity. For the algorithmic computability, the concept of a Turing machine is used as it provides fundamental performance limits for today's digital computers. In this paper, it is shown that the forward secret key capacity with a noisy public channel is not computable and consequently, there is no algorithm that can simulate or compute the secret key capacity; even if there are no limitations on computational complexity and computing power. On the other hand, if the public channel is noiseless so that there are no rate constraints on the public communication, the secret key capacity is a computable continuous function, which is the strongest form of computability. A similar behavior is subsequently observed for the authentication problem: The secure authentication capacity under storage rate and privacy leakage rate constraints is not computable, while the case without privacy leakage rate constraints is computable.

Enterprise Resilience Assessment—A Quantitative Approach

Enterprise resilience is a key capacity to guarantee enterprises’ long-term continuity. This paper proposes a quantitative approach to enhance enterprise resilience by selecting optimal preventive actions to be activated to cushion the impact of disruptive events and to improve preparedness capability, one of the pillars of the enterprise resilience capacity. The proposed algorithms combine the dynamic programming approach with attenuation formulas to model real improvements when a combined set of preventive actions is activated for the same disruptive event. A numerical example is presented that shows remarkable reductions in the expected annual cost due to potential disruptive events.

The Secret Key Capacity of a Class of Noisy Channels with Correlated Sources

The Secret Key Capacity of a Class of Noisy Channels with Correlated Sources

The Secret Key Capacity of a Class of Noisy Channels with Correlated Sources.

This paper investigates the problem of secret key generation over a wiretap channel when the terminals observe correlated sources. These sources are independent of the main channel and the users overhear them before the transmission takes place. A novel outer bound is proposed and, employing a previously reported inner bound, the secret key capacity is derived under certain less-noisy conditions on the channel or source components. This result improves upon the existing literature where the more stringent condition of degradedness is required. Furthermore, numerical evaluation of the achievable scheme and previously reported results for a binary model are presented; a comparison of the numerical bounds provides insights on the benefit of the chosen scheme.

Implementing land degradation neutrality: From policy challenges to policy opportunities for national sustainable development

The principles of the Land Degradation Neutrality conceptual framework are core to this special issue, and the research papers included aim to support national sustainable development aspirations by providing guidance on policies, procedures and governance needed to regulate national land use to avoid further net loss of productive lands. Relevant to this special issue is science-based evidence on policy principles, rules and procedures to design national actions that contribute to LDN implementation; and on indicator systems and metrics to monitor and maintain a nationally desired status of the land. Contributions also identify key human, technical and institutional capacity needs at national and sub-national levels; provide new information and knowledge for framing future policy-oriented research, and technology to strive to achieve, and to maintain, land degradation neutrality at global and national scales.

Impact of Aging on Empathy: Review of Psychological and Neural Mechanisms.

Empathy in aging is a key capacity because it affects the quality of older adults’ relationships and reduced levels are associated with greater loneliness. Many older adults also find themselves in the role of a caregiver to a loved one, and thus empathy is critical for the success of the caregiver–patient relationship. Furthermore, older adults are motivated to make strong emotional connections with others, as highlighted in the socioemotional selectivity theory. Consequently, reductions in empathy could negatively impact their goals. However, there is growing evidence that older adults experience at least some changes in empathy, depending on the domain. Specifically, the state of the research is that older adults have lower cognitive empathy (i.e., the ability to understand others’ thoughts and feelings) than younger adults, but similar and in some cases even higher levels of emotional empathy (i.e., the ability to feel emotions that are similar to others’ or feel compassion for them). A small number of studies have examined the neural mechanisms for age-related differences in empathy and have found reduced activity in a key brain area associated with cognitive empathy. However, more research is needed to further characterize how brain changes impact empathy with age, especially in the emotional domain of empathy. In this review, we discuss the current state of the research on age-related differences in the psychological and neural bases of empathy, with a specific comparison of the cognitive versus emotional components. Finally, we highlight new directions for research in this area and examine the implications of age-related differences in empathy for older adults.