The Road to Better STM

There are currently just under 7000 functioning satellites in space and this is set to rapidly increase over the course of this decade. According to a recent Euroconsult report, during the period up to 2031, on average over 2,500 satellites will be launched every year. 83% of these are expected to be part of large constellations. This huge increase in space traffic, as well as the complexities of a multi-orbit environment and the ever-increasing amount of debris, has brought STM back to the fore. A collision between a satellite and another space object has the potential to not only cause significant damage to the satellite but could also add thousands of new pieces of debris to Earth\u27s orbit which is obviously going to exacerbate the problem. If space activity is to remain sustainable for the long term, the industry requires much better space situational awareness (SSA) and space traffic management (STM) than is currently in existence. Fit for purpose STM services are critical for space safety and sustainability of the industry as a whole. However, STM is a complex issue and there are a number of challenges to overcome along the road to better STM services. . The journey to better STM is indeed a difficult road to navigate, yet there are a number of key steps that if taken, will help to ensure that STM services are at least heading in the right direction

Work-Life Balance through Sabbath Keeping for Cornerstone Chinese Alliance Church in Markham, Ontario

The goal of this paper is to help English-speaking adults from Cornerstone Chinese Alliance Church in Markham, Ontario achieve rest, renewal, and reconnection with God and others to bring a sense of balance between work and life. To achieve this purpose, a pilot project will be conducted within the Sunday School ministry with a small number of English-speaking leaders to enable them to practice Sabbath keeping through discussion, accountability, and peer mentoring. The content of this project will go over four key areas of Sabbath keeping, which are rest, recreation, worship, and relationship. Cornerstone Chinese Alliance Church is situated in the fast growing, affluent suburban community of Markham, Ontario, which many consider to be the high-tech capital of Canada. The affluent lifestyle is enjoyed by young professionals and families with dual incomes. Church members often lead aspiring careers with upward mobility and monetary returns. The drive to succeed, coupled with the value of hard work has led to an overemphasis on careers at the expense of self-care, family, and spiritual health. This imbalanced lifestyle is a breeding ground for issues such as burnout, depression, and divorce. This paper contains three major sections. The first looks at Cornerstone Chinese Alliance Church’s context: location, demographics, sources of growth, challenges and opportunities to teach and practice Sabbath keeping. The second section of this paper will focus on the theology of the Sabbath, which reflects on different theological viewpoints of Sabbath keeping to explore possible correctives to imbalanced lifestyles. The final section of this paper provides a strategy for launching an integrated approach through the Sunday School ministry that includes formal instruction, discussion, peer mentoring, and accountability groups. The end result should yield a renewed mind, a focused commitment to Christ, and a healthy work-life balance

On Extracting Common Random Bits From Correlated Sources on Large Alphabets

Suppose Alice and Bob receive strings X=(X1,...,Xn) and Y=(Y1,...,Yn) each uniformly random in [s]n, but so that X and Y are correlated. For each symbol i, we have that Yi=Xi with probability 1-ε and otherwise Yi is chosen independently and uniformly from [s]. Alice and Bob wish to use their respective strings to extract a uniformly chosen common sequence from [s]k, but without communicating. How well can they do? The trivial strategy of outputting the first k symbols yields an agreement probability of (1-ε+ε/s)k. In a recent work by Bogdanov and Mossel, it was shown that in the binary case where s=2 and k=k(ε) is large enough then it is possible to extract k bits with a better agreement probability rate. In particular, it is possible to achieve agreement probability (kε)-1/2·2-kε/(2(1-ε/2)) using a random construction based on Hamming balls, and this is optimal up to lower order terms. In this paper, we consider the same problem over larger alphabet sizes s and we show that the agreement probability rate changes dramatically as the alphabet grows. In particular, we show no strategy can achieve agreement probability better than (1-ε)k(1+δ(s))k where δ(s)→ 0 as s→∞. We also show that Hamming ball-based constructions have much lower agreement probability rate than the trivial algorithm as s→∞. Our proofs and results are intimately related to subtle properties of hypercontractive inequalities

Agreement between bioelectrical impedance and dual energy X-ray absorptiometry in assessing fat, lean and bone mass changes in adults after a lifestyle intervention

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Marine n-3 fatty acid consumption in a Norwegian renal transplant cohort:Comparison of a food frequency questionnaire with plasma phospholipid marine n-3 levels

BackgroundHigh levels of plasma marine n-3 fatty acids (n-3FAs) are associated with improved patient and graft survival in renal transplant recipients (RTRs). The aim of this study was to evaluate the utility of a new food frequency questionnaire (FFQ) to estimate marine n-3FA consumption in future epidemiological research.MethodsWe developed an FFQ with a simple design of 10 questions to assess intake of marine sources of n-3FAs. RTRs included in the recent ORENTRA trial (n = 132) completed the study FFQ at the baseline visit eight weeks after engraftment and at the end of study visit one year post-transplant. We measured the reference biomarker plasma phospholipid (PL) marine n-3FA levels by gas chromatography at the same time points to evaluate association and degree of agreement between FFQ based marine n-3FA consumption estimates and the biomarker.ResultsThe median plasma PL marine n-3FA level was 6.0 weight percentage (wt)% (interquartile range [IQR] 4.7 to 7.3) at baseline and 6.3 wt% (IQR 4.8 to 7.4) at end of study. Median FFQ based marine n-3FA consumption estimates were 22.8 g/month (IQR 13.0 to 34.0) at baseline and 20.3 g/month (IQR 14.5 to 32.3) at end of study. FFQ based marine n-3FA consumption estimates showed a moderate correlation with plasma PL marine n-3FA levels at baseline (Spearman's correlation coefficient rs = 0.43, pConclusionsMarine n-3FA consumption estimates based on the FFQ showed a moderate correlation with the reference biomarker plasma PL marine n-3FA levels. The FFQ might be useful in epidemiological studies where resources are limited

A new multivariate nonlinear time series model for portfolio risk measurement: the threshold copula-based TAR approach

We propose a threshold copula-based nonlinear time series model for evaluating quantitative risk measures for financial portfolios with a flexible structure to incorporate nonlinearities in both univariate (component) time series and their dependent structure. We incorporate different dependent structures of asset returns over different market regimes, which are manifested in their price levels. We estimate the model parameters by a two-stage maximum likelihood method. Real financial data and appropriate statistical tests are used to illustrate the efficacy of the proposed model. Simulated results for sampling distribution of parameters estimates are given. Empirical results suggest that the proposed model leads to significant improvement of the accuracy of value-at-risk forecasts at the portfolio le