Design study of a low cost civil aviation GPS receiver system

A low cost Navstar receiver system for civil aviation applications was defined. User objectives and constraints were established. Alternative navigation processing design trades were evaluated. Receiver hardware was synthesized by comparing technology projections with various candidate system designs. A control display unit design was recommended as the result of field test experience with Phase I GPS sets and a review of special human factors for general aviation users. Areas requiring technology development to ensure a low cost Navstar Set in the 1985 timeframe were identified

Monetary union and economic growth

This paper discusses possible links between monetary arrangements in particular monetary union and economic growth. It is stressed that growth depends ultimately on how the real economy works: there is no monetary magic that can conjure up growth. But monetary policy can contribute to conditions for sustainable growth by securing and maintaining price stability; monetary union might extend this. It might also deepen the single market. The elimination of nominal exchange rate movement among members of the union removes some sources of shock but also some ways of adjusting to shocks. This underlines the importance of other adjustment mechanism especially supply-side flexibility, which is crucial for growth in any event.

Advanced software techniques for space shuttle data management systems Final report

Airborne/spaceborn computer design and techniques for space shuttle data management system

Further Monetary Easing Policies under the Non-negativity Constraints of Nominal Interest Rates: Summary of the Discussion Based on Japan's Experience

This paper examines issues surrounding monetary policy under zero interest rates based on one and a half yearfs experience in Japan. After reviewing the market development in Japan, it summarizes the transmission mechanism of monetary policy under zero nominal interest rates, and considers what would be the likely policy options if a central bank were to conduct further monetary easing. Specifically, a more detailed policy announcement is regarded as feasible, less costly, and the less risky option, although additional effects of monetary easing through this measure are relatively limited. On the other hand, introduction of a temporary fixed exchange rate system and a huge increase in the outright purchase of medium- and long-term government bonds can induce relatively large effects, although the uncertainty in the effects as well as the accompanied costs and risks may be very large. In addition, the paper considers the validity of introducing inflation targeting. It summarizes that inflation targeting is not necessarily easy to distinguish from traditional policy management based on an overall consideration. Furthermore, given recent tendencies in Japan, the paper argues that the introduction of inflation targeting in the current situation might impair the conduct of monetary policy in the absence of preconditions for benefiting from its intrinsic merits.

White Paper from Workshop on Large-scale Parallel Numerical Computing Technology (LSPANC 2020): HPC and Computer Arithmetic toward Minimal-Precision Computing

In numerical computations, precision of floating-point computations is a key factor to determine the performance (speed and energy-efficiency) as well as the reliability (accuracy and reproducibility). However, precision generally plays a contrary role for both. Therefore, the ultimate concept for maximizing both at the same time is the minimal-precision computing through precision-tuning, which adjusts the optimal precision for each operation and data. Several studies have been already conducted for it so far (e.g. Precimoniuos and Verrou), but the scope of those studies is limited to the precision-tuning alone. Hence, we aim to propose a broader concept of the minimal-precision computing system with precision-tuning, involving both hardware and software stack. In 2019, we have started the Minimal-Precision Computing project to propose a more broad concept of the minimal-precision computing system with precision-tuning, involving both hardware and software stack. Specifically, our system combines (1) a precision-tuning method based on Discrete Stochastic Arithmetic (DSA), (2) arbitrary-precision arithmetic libraries, (3) fast and accurate numerical libraries, and (4) Field-Programmable Gate Array (FPGA) with High-Level Synthesis (HLS). In this white paper, we aim to provide an overview of various technologies related to minimal- and mixed-precision, to outline the future direction of the project, as well as to discuss current challenges together with our project members and guest speakers at the LSPANC 2020 workshop; https://www.r-ccs.riken.jp/labs/lpnctrt/lspanc2020jan/

Gerrymandering and Compactness: Implementation Flexibility and Abuse

The shape of an electoral district may suggest whether it was drawn with political motivations, or gerrymandered. For this reason, quantifying the shape of districts, in particular their compactness, is a key task in politics and civil rights. A growing body of literature suggests and analyzes compactness measures mathematically, but little consideration has been given to how these scores should be calculated in practice. Here, we consider the effects of a number of decisions that must be made in interpreting and implementing a set of popular compactness scores. We show that the choices made in quantifying compactness may themselves become political tools, with seemingly innocuous decisions leading to disparate scores. We show that when the full range of implementation flexibility is used, it can be abused to make clearly gerrymandered districts appear quantitatively reasonable. This complicates using compactness as a legislative or judicial standard to counteract unfair redistricting practices. This paper accompanies the release of packages in C++, Python, and R which correctly, efficiently, and reproducibly calculate a variety of compactness scores.Comment: 10 pages, 17 figures, 1 tabl

Chosen Numerical Algorithms for Interval Finite Element Analysis

AbstractOur paper presents chosen computational algorithms for solution of finite element models with structural uncertainties. An application of the chosen approaches will be presented–the first one, a simple combination of only inf-values or only sup-values; the second one presents full combination of all inf-sup values; the third one uses the optimizing process as a tool for finding out an inf-sup solution and last one is the Monte Carlo method as a comparison tool

The development of novel interchangeable pistons for pressure performance optimization in a gas-operated dead weight pressure balance

The texture of surfaces within a piston–cylinder assembly (PCA) can influence the pressure performance of gas-operated dead weight pressure balances (DWPBs). In order to systematically study this response, it has been necessary to design, develop and manufacture uniquely interchangeable 35mm diameter PCAs for use in a novel hybrid gas-operated DWPB with high mechanical, thermal and pressure stability. This work reports the development of the PCAs and the validation of the DWPB design, allowing the performance characteristics of the interchangeable PCAs to be understood, in terms of variations of effective area calculations. This is achieved by investigating the pressure responses of the DWPBs by changing the speed and direction of rotation. The results demonstrate the stability of the gas-operated DWPB design when used in gauge mode, and importantly allow the verification of the performance of the interchangeable PCAs