Strengthening Somalia’s Systems Smartly: A Country Systems Risk Benefit Analysis

Somalia’s donors are unambiguous: statebuilding is a key, if not the key, goal of their development assistance. This paper examines donors’ decision-making about the use of country systems (UCS), an internationally recognized tool for statebuilding, exploring both the perceived and actual risks and benefits associated with it. UCS refers to a variety of ways in which international partners can engage with national counterparts to deliver aid ranging from alignment with national priorities to direct implementation by government. While using country systems comes with risks, so do alternative delivery modalities. Considering the risks and benefits both of UCS and its alternatives side-by-side may help in achieving a mix of delivery modalities that better serves donors’ and government’s shared statebuilding objectives

07381 Abstracts Collection -- Cryptography

From 16.09.2007 to 21.09.2007 the Dagstuhl Seminar 07381 ``Cryptography\u27\u27 was held in the International Conference and Research Center (IBFI), Schloss Dagstuhl. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

07381 Executive Summary - Cryptography

The topics covered in the seminar spanned most areas of cryptography, in one way or another, both in terms of the types of schemes (public-key cryptography, symmetric cryptography, hash functions and other cryptographic functions, multi-party protocols, etc.) and in terms of the mathematical methods and techniques used (algebra, number theory, elliptic curves, probability theory, information theory, combinatorics, quantum theory, etc.). The range of applications addressed in the various talks was broad, ranging from secure communication, key management, authentication, digital signatures and payment systems to e-voting and Internet security. While the initial plan had been to focus more exclusively on public-key cryptography, it turned out that this sub-topic branches out into many other areas of cryptography and therefore the organizers decided to expand the scope, emphasizing quality rather than close adherence to public-key cryptography. This decision turned out to be a wise one. What was common to almost all the talks is that rigorous mathematical proofs for the security of the presented schemes were given. In fact, a central topic of many of the talks were proof methodologies for various contexts

Electric Drives with Wide Bandgap Devices for Two-Phase Very Low Inductance Machines

Slotless and coreless machines with low inductance and low core losses are attractive for high speed and high power density applications. With the increase in fundamental frequency, typical drive implementations using conventional silicon-based devices are performance limited and also produce large current and torque ripples. This paper presents a systematic study of proposed drive configurations implemented with wide bandgap (WBG) devices in order to mitigate such issues for 2-phase very low inductance machines. Two inverter topologies, i.e., a dual H-bridge inverter with maximum redundancy and survivability and a 3-leg inverter for reduced cost, are considered. Feasible modulation schemes are derived based on theoretical analysis and the associated maximum output voltages are identified. Simulation and experimental results are provided to validate the feasibility of drive systems and the effectiveness of analysis

Design Optimization and Comparison of Direct-Drive Outer-Rotor SRMs Based on Fast Current Profile Estimation and Transient FEA

Outer-rotor switched reluctance machines (SRMs) have drawn much attention as promising candidates for in-wheel direct-drive motors of future electric vehicles. This article presents a systematic performance comparison of three outer-rotor SRM topologies for in-wheel traction applications in terms of the specific torque, electromagnetic efficiency, torque ripple, radial force, and mechanical aspects. A generalized design optimization framework for SRMs is proposed to enable the fast evaluation of large numbers of designs generated from the differential evolution by incorporating an analytical current profile estimation into the transient finite element analysis. The relationship between the saliency ratio and converter volt-ampere rating is also discussed. The calculations are then benchmarked with the experimental results from an existing prototype. The effectiveness of the performance prediction method and the proposed optimization approach is validated

Detroit Works Long-Term Planning Project: Engagement Strategies for Blending Community and Technical Expertise

In January 2013, civic leaders, community stakeholders, and residents came together to release Detroit Future City: 2012 Detroit Strategic Framework Plan, a guiding blueprint for transforming Detroit from its current state of population loss and excessive vacancy into a model for the reinvention of post-industrial American cities. Three years prior, the U.S. Census had reported that the city had lost 24% of its population over the last decade and had experienced a 20% increase in vacant and abandoned property, bringing total vacancy to roughly the size of Manhattan. In addition to physical and economic challenges, Detroiters had also acknowledged significant barriers to effective civic engagement. Foremost among these barriers were a profound sense of immobilization, planning fatigue, and a general perception of cynicism about planning and engagement efforts. These challenges were compounded by historic racial dynamics and tension. This case study elaborates on the comprehensive and innovative civic engagement executed in a citywide planning process called the Detroit Works Project, which took place from late 2010 through late 2012. For the citywide planning process to be successful and sustainable, civic leaders and project funders committed to a planning initiative that would be different from previous efforts, in large part because the “owners” of the process would be diverse and inclusive across all community sectors. The case study, written by three of the key consultants from the project, describes four key civic engagement strategies deployed in the creation of the strategic framework: (1) addressing profound challenges of culture, race, and politics by deliberately building trust; (2) elevating community expertise by fostering a sense of ownership of the process; (3) blending technical and community expertise; and (4) viewing civic engagement as an ongoing two-way conversation rather than a series of large-scale episodic events. This article elaborates on important lessons that other communities might learn from Detroit’s planning initiative in relation to these strategies. It concludes with a brief summary of the results and implications of the civic engagement process

Practical Fully Secure Three-Party Computation via Sublinear Distributed Zero-Knowledge Proofs

Secure multiparty computation enables a set of parties to securely carry out a joint computation on their private inputs without revealing anything but the output. A particularly motivated setting is that of three parties with a single corruption (hereafter denoted 3PC). This 3PC setting is particularly appealing for two main reasons: (1) it admits more efficient MPC protocols than in other standard settings; (2) it allows in principle to achieve full security (and fairness). Highly efficient protocols exist within this setting with security against a semi-honest adversary; however, a significant gap remains between these and protocols with stronger security against a malicious adversary. In this paper, we narrow this gap within concretely efficient protocols. More explicitly, we have the following contributions: * Concretely Efficient Malicious 3PC. We present an optimized 3PC protocol for arithmetic circuits over rings with (amortized) communication of 1 ring element per multiplication gate per party, matching the best semi-honest protocols. The protocol applies also to Boolean circuits, significantly improving over previous protocols even for small circuits. Our protocol builds on recent techniques of Boneh et al.\ (Crypto 2019) for sublinear zero-knowledge proofs on distributed data, together with an efficient semi-honest protocol based on replicated secret sharing (Araki et al., CCS 2016). We present a concrete analysis of communication and computation costs, including several optimizations. For example, for 40-bit statistical security, and Boolean circuit with a million (nonlinear) gates, the overhead on top of the semi-honest protocol can involve less than 0.5KB of communication {\em for the entire circuit}, while the computational overhead is dominated by roughly 30 multiplications per gate in the field $F_{2^{47}}$. In addition, we implemented and benchmarked the protocol for varied circuit sizes. * Full Security. We augment the 3PC protocol to further provide full security (with guaranteed output delivery) while maintaining amortized 1 ring element communication per party per multiplication gate, and with hardly any impact on concrete efficiency. This is contrasted with the best previous 3PC protocols from the literature, which allow a corrupt party to mount a denial-of-service attack without being detected

Time-dependent ARMA modeling of genomic sequences

<p>Abstract</p> <p>Background</p> <p>Over the past decade, many investigators have used sophisticated time series tools for the analysis of genomic sequences. Specifically, the correlation of the nucleotide chain has been studied by examining the properties of the power spectrum. The main limitation of the power spectrum is that it is restricted to stationary time series. However, it has been observed over the past decade that genomic sequences exhibit non-stationary statistical behavior. Standard statistical tests have been used to verify that the genomic sequences are indeed not stationary. More recent analysis of genomic data has relied on time-varying power spectral methods to capture the statistical characteristics of genomic sequences. Techniques such as the evolutionary spectrum and evolutionary periodogram have been successful in extracting the time-varying correlation structure. The main difficulty in using time-varying spectral methods is that they are extremely unstable. Large deviations in the correlation structure results from very minor perturbations in the genomic data and experimental procedure. A fundamental new approach is needed in order to provide a stable platform for the non-stationary statistical analysis of genomic sequences.</p> <p>Results</p> <p>In this paper, we propose to model non-stationary genomic sequences by a time-dependent autoregressive moving average (TD-ARMA) process. The model is based on a classical ARMA process whose coefficients are allowed to vary with time. A series expansion of the time-varying coefficients is used to form a generalized Yule-Walker-type system of equations. A recursive least-squares algorithm is subsequently used to estimate the time-dependent coefficients of the model. The non-stationary parameters estimated are used as a basis for statistical inference and biophysical interpretation of genomic data. In particular, we rely on the TD-ARMA model of genomic sequences to investigate the statistical properties and differentiate between coding and non-coding regions in the nucleotide chain. Specifically, we define a quantitative measure of randomness to assess how far a process deviates from white noise. Our simulation results on various gene sequences show that both the coding and non-coding regions are non-random. However, coding sequences are "whiter" than non-coding sequences as attested by a higher index of randomness.</p> <p>Conclusion</p> <p>We demonstrate that the proposed TD-ARMA model can be used to provide a stable time series tool for the analysis of non-stationary genomic sequences. The estimated time-varying coefficients are used to define an index of randomness, in order to assess the statistical correlations in coding and non-coding DNA sequences. It turns out that the statistical differences between coding and non-coding sequences are more subtle than previously thought using stationary analysis tools: Both coding and non-coding sequences exhibit statistical correlations, with the coding regions being "whiter" than the non-coding regions. These results corroborate the evolutionary periodogram analysis of genomic sequences and revoke the stationary analysis' conclusion that coding DNA behaves like random sequences.</p