Three Generations of Intergenerational Transmission of Neighbourhood Context

The literature on intergenerational contextual mobility has shown that neighbourhood status is partly ‘inherited’ from parents by children. Children who spend their childhood in deprived neighbourhoods are more likely to live in such neighbourhoods as adults. It has been suggested that such transmission of neighbourhood status is also relevant from a multiple generation perspective. To our knowledge, however, this has only been confirmed by simulations and not by empirical research. This study uses actual empirical data covering the entire Swedish population over a 25-year period, to investigate intergenerational similarities in neighbourhood status for three generations of Swedish women. The findings suggest that the neighbourhood environments of Swedish women are correlated with the neighbourhood statuses of their mothers and, to some extent, grandmothers. These results are robust over two different analytical strategies—comparing the neighbourhood status of the three generations at roughly similar ages and at the same point in time—and two different spatial scales. We argue that the finding of such effects in (relatively egalitarian) Sweden implies that similar, and possibly stronger, patterns are likely to exist in other countries as well.

Characterizing COVID-19 Transmission: Incubation Period, Reproduction Rate, and Multiple-Generation Spreading

Understanding the transmission process is crucial for the prevention and mitigation of COVID-19 spread. This paper contributes to the COVID-19 knowledge by analyzing the incubation period, the transmission rate from close contact to infection, and the properties of multiple-generation transmission. The data regarding these parameters are extracted from a detailed line-list database of 9,120 cases reported in mainland China from January 15 to February 29, 2020. The incubation period of COVID-19 has a mean, median, and mode of 7.83, 7, and 5 days, and, in 12.5% of cases, more than 14 days. The number of close contacts for these cases during the incubation period and a few days before hospitalization follows a log-normal distribution, which may lead to super-spreading events. The disease transmission rate from close contact roughly decreases in line with the number of close contacts with median 0.13. The average secondary cases are 2.10, 1.35, and 2.2 for the first, second, and third generations conditioned on at least one offspring. However, the ratio of no further spread in the 2nd, 3rd, and 4th generations are 26.2, 93.9, and 90.7%, respectively. Moreover, the conditioned reproduction number in the second generation is geometrically distributed. Our findings suggest that, in order to effectively control the pandemic, prevention measures, such as social distancing, wearing masks, and isolating from close contacts, would be the most important and least costly measures.

Deterministic Secure Quantum Communication on the BB84 System

In this paper, we propose a deterministic secure quantum communication (DSQC) protocol based on the BB84 system. We developed this protocol to include quantum entity authentication in the DSQC procedure. By first performing quantum entity authentication, it was possible to prevent third-party intervention. We demonstrate the security of the proposed protocol against the intercept-and-re-send attack and the entanglement-and-measure attack. Implementation of this protocol was demonstrated for quantum channels of various lengths. Especially, we propose the use of the multiple generation and shuffling method to prevent a loss of message in the experiment.

Hybrid parallel adder for 3X multiple generation in radix-8 booth encoding using fast carry tree structure

Purpose In most commercial processors, enhancing the speed of multiplication using radix-8 booth encoding is the preferred option. In radix-8 architecture, the 3X(= 2X + X) multiple generation is a major bottleneck. This paper aims to propose a parallel implementation scheme recognizing the symmetry in the carry recurrence equations of 3X multiples. The proposed architecture evaluates the odd (H) and even (K) carry signals separately. As prefix tree structure offers fast carry propagation, the parallel implementation is based on a hybrid style of two popular prefix architectures. Design/methodology/approach The performance of the proposed architecture is evaluated using Cadence TSMC 180 nm library. A comparison of performance parameters with other architectures has been carried out to highlight the architectural advantages of the proposed architecture. Findings A comparison of performance parameters with others shows that the proposed architecture has a reduced critical path and a commensurate improvement in delay for a bit width of 64. It is shown that up to 32 bits, this parallel architecture has a superior performance and would be the appropriate choice for Application Specific Integrated Circuit (ASIC) implementation. It has also been suggested that higher-order bit widths could be implemented using a modular arrangement. Originality/value This paper proposes a new parallel architecture for hard multiple (3X) generation in Radix-8 Booth encoding. As the multiplication is the key operation in digital signal processors, this type of high-speed architectures gains importance in the future processor design. Defence applications such as target finding and multiple target recognitions and image processing applications necessitate this type of high-speed multipliers. Also, it is appropriate for the ASIC implementation. The authors would like to mention that this paper is not yet published anywhere, and it is the research paper of Dr R. Nirmaladevi.