Variance estimators in critical branching processes with non-homogeneous immigration

The asymptotic normality of conditional least squares estimators for the offspring variance in critical branching processes with non-homogeneous immigration is established, under moment assumptions on both reproduction and immigration. The proofs use martingale techniques and weak convergence results in Skorokhod spaces.Comment: Accepted for publication in Math Population Studie

Religion in language policy, and the survival of Syriac

Throughout Islamic era, the Syriac language remained the language of the majority despite Arabic hegemony. The decline of the Syriac accompanied the decline of Christianity in the East, and was affected by the policies of rival religious and nationalist groups. By considering the current conditions under which Syriac speakers live, and the renewed interest in reviving the language among Christian communities in the modern Fertile Crescent, this thesis will examine the causes of decline over the centuries, and the possibilities for the revival of Syriac in modern times. The present research examines how religion contributed to the shaping of language policy in the case of Syriac

Shear Bond Strength of Chemically-Cured and Light-Cured Bulk Composites as Different Temperatures

The purpose of this study is to compare the shear-bond strength of a chemically-cured bulk composite and a light-cured bulk composite. The chemically-cured bulk composite was delivered at room temperature. The light-cured composite was delivered at room temperature and at 155 degrees Fahrenheit. The null hypothesis is that there is no difference among the three groups

Implication of Leadership Change on Poverty Trends in Nigeria

Nigeria has a great potential for economic growth ranging from enormous rich natural resources to a large population size significant for both domestic and foreign investments. However, the poverty rate in the country has grown beyond the imaginable threshold since the 1980s, despite high revenues from exports of crude oil. This study takes a descriptive overview of the poverty rate in Nigeria with reference to leadership change between 1980 and 2011. The results show a continuously increasing poverty rate within the period with the highest poverty rate estimated at 71.5%. The slide drop in the poverty rate to an average of  56.1% between 1999 and 2007 could be attributed to the measures taken by the government against administrative corruption, increased domestic and foreign investments, as well as some implemented agricultural policies. From the results, it can be inferred that the increase in the poverty rate in Nigeria, among other factors, could be attributed to inadequate and poorly implemented agricultural policies, political crisis and deep rooted administrative corruption worsened by high population growth and insecurity in the country. This study, therefore, recommends that the government should design a more transparent framework to help eradicate corruption among leaders in different sectors of the economy and focus more on agricultural development which has been the foundation of economic development and major means of livelihood of the majority of people in the country before the discovery of crude oil. It is also recommended that stakeholders in politics and the entire people of Nigeria should assist the government to maintain a secure, politically stable and safe economic environment to attract robust investments that would help improve the income and wellbeing of the people. Keywords: Leadership change, poverty, poverty trends, poverty rate, Nigeri

Stochastic Testing Simulator for Integrated Circuits and MEMS: Hierarchical and Sparse Techniques

Process variations are a major concern in today's chip design since they can significantly degrade chip performance. To predict such degradation, existing circuit and MEMS simulators rely on Monte Carlo algorithms, which are typically too slow. Therefore, novel fast stochastic simulators are highly desired. This paper first reviews our recently developed stochastic testing simulator that can achieve speedup factors of hundreds to thousands over Monte Carlo. Then, we develop a fast hierarchical stochastic spectral simulator to simulate a complex circuit or system consisting of several blocks. We further present a fast simulation approach based on anchored ANOVA (analysis of variance) for some design problems with many process variations. This approach can reduce the simulation cost and can identify which variation sources have strong impacts on the circuit's performance. The simulation results of some circuit and MEMS examples are reported to show the effectiveness of our simulatorComment: Accepted to IEEE Custom Integrated Circuits Conference in June 2014. arXiv admin note: text overlap with arXiv:1407.302

On the effective reconstruction of expectation values from ab initio quantum embedding

Quantum embedding is an appealing route to fragment a large interacting quantum system into several smaller auxiliary `cluster' problems to exploit the locality of the correlated physics. In this work we critically review approaches to recombine these fragmented solutions in order to compute non-local expectation values, including the total energy. Starting from the democratic partitioning of expectation values used in density matrix embedding theory, we motivate and develop a number of alternative approaches, numerically demonstrating their efficiency and improved accuracy as a function of increasing cluster size for both energetics and non-local two-body observables in molecular and solid state systems. These approaches consider the $N$-representability of the resulting expectation values via an implicit global wave~function across the clusters, as well as the importance of including contributions to expectation values spanning multiple fragments simultaneously, thereby alleviating the fundamental locality approximation of the embedding. We clearly demonstrate the value of these introduced functionals for reliable extraction of observables and robust and systematic convergence as the cluster size increases, allowing for significantly smaller clusters to be used for a desired accuracy compared to traditional approaches in ab initio wave~function quantum embedding.Comment: 20 page

Leveraging the SRTP Protocol for Over-the-Network Memory Acquisition of a GE Fanuc Series 90-30

Programmable Logic Controllers (PLCs) are common components implemented across many industries such as manufacturing, water management, travel, aerospace and hospitals to name a few. Given their broad deployment in critical systems, they became and still are a common target for cyber attacks; the most prominent one being Stuxnet. Often PLCs (especially older ones) are only protected by an outer line of defense (e.g., a firewall) but once an attacker gains access to the system or the network, there might not be any other defense layers. In this scenario, a forensic investigator should not rely on the existing software as it might have been compromised. Therefore, we reverse engineered the GE-SRTP network protocol using a GE Fanuc Series 90-30 PLC and provide two major contributions: We first describe the Service Request Transport protocol (GE-SRTP) which was invented by General Electric (GE) and is used by many of their Ethernet connected controllers. Note, to the best of our knowledge, prior to this work, no publicly available documentation on the protocol was available affording users\u27 security by obscurity. Second, based on our understanding of the protocol, we implemented a software application that allows direct network-based communication with the PLC (no intermediate server is needed). While the tool\u27s forensic mode is harmless and only allows for reading registers, we discovered that one can manipulate/write to the registers in its default configuration, e.g., turn off the PLC, or manipulate the items/processes it controls