An Analysis of the Effect of Saturday Home Football Games on Physical Use of University Libraries

Objective – Library science literature lacks studies on the effect of external events on the physical use of libraries, leaving a gap in understanding of would-be library patrons’ time use choices when faced with the option of using the library or attending time-bound, external events. Within academic libraries in about 900 colleges and universities in the US, weekend time use may be affected by football games. This study sought to elucidate the effect of external events on physical use of libraries by examining the effect of Saturday home football games on the physical use of the libraries in a large, academic institution. Methods – This study used a retrospective, observational study design. Gate count data for all Saturdays during the fall semesters of 2013-2018 were collected for the two primary libraries at East Carolina University (main campus’ Academic Library Services [ALS] and Laupus, a health sciences campus library), along with data on the occurrence of home football games. The relationship between gate counts and the occurrence of home football games was assessed using an independent samples t-test. Results – Saturday home football games decreased the gate count at both ALS and Laupus. For ALS, the mean physical use of the library decreased by one third (34.4%) on Saturdays with a home game. For Laupus, physical use of the library decreased by almost a quarter (22%) on Saturdays with a home game. Conclusion – Saturday home football games alter the physical use of academic libraries, decreasing the number of patrons entering the doors. Libraries may be able to adjust staffing based on reduced use of library facilities during these events.

Clifford Circuit Optimization with Templates and Symbolic Pauli Gates

The Clifford group is a finite subgroup of the unitary group generated by the Hadamard, the CNOT, and the Phase gates. This group plays a prominent role in quantum error correction, randomized benchmarking protocols, and the study of entanglement. Here we consider the problem of finding a short quantum circuit implementing a given Clifford group element. Our methods aim to minimize the entangling gate count assuming all-to-all qubit connectivity. First, we consider circuit optimization based on template matching and design Clifford-specific templates that leverage the ability to factor out Pauli and SWAP gates. Second, we introduce a symbolic peephole optimization method. It works by projecting the full circuit onto a small subset of qubits and optimally recompiling the projected subcircuit via dynamic programming. CNOT gates coupling the chosen subset of qubits with the remaining qubits are expressed using symbolic Pauli gates. Software implementation of these methods finds circuits that are only 0.2% away from optimal for 6 qubits and reduces the two-qubit gate count in circuits with up to 64 qubits by 64.7% on average, compared with the Aaronson-Gottesman canonical form.

A Double Bit Approximate Adder Providing a New Design Perspective for Gate-Level Design

In the modern Block-chain and Artificial Intelligence era, energy efficiency has become one of the most important design concerns. Approximate computing is a new and an evolving field promising to provide energy-accuracy trade-off. Several applications are tolerant to small degradation in results, and hence tasks like image and video processing are candidates to benefit from Approximate Computing. In this paper, we propose a new design approach for designing approximate adders and further optimize the accuracy and cost metrics. Our approach is based on minimizing the errors while cascading more than one 1-bit adder. We insert [Formula: see text] on specific locations to achieve a reasonable circuit minimization and reduce the [Formula: see text] cost. We compare our design with exact adder and relevant state-of-the-art approximate adders. Through analysis and simulations, we show that our approach provides higher accuracy and far better performance compared with other designs. The proposed double bit approximate adder provides more than 25% savings in gate count compared with the exact adder, has a mean absolute error of 0.25 which is lowest among all the reference approximate adders and reduces the power-delay product by more than 60% compared to the exact adder. When employed for image filtering, the proposed design provides a [Formula: see text] of 96%, a [Formula: see text] of 95% and a [Formula: see text] of 91% relative to the actual results, while the second best approximate adder only achieves 64%, 54% and 71% of these image quality metrics, respectively.

Impact of COVID-19 on the use of the academic library

PurposeThis study examines differences in library use patterns (in-person visits, online use, reference transactions, library resource and services use) pre-COVID-19 and during the COVID-19 pandemic through multiple data sets.Design/methodology/approachUsing library statistics collected during 2017/2018 and 2020/2021 and student responses to a biennial library use survey distributed in 2018 and 2021, the potential impact of the pandemic on users' behaviors was explored.FindingsLibrary use statistics and the biennial survey responses demonstrate that users' overall library use was impacted by COVID-19. Both the library's gate count and students' frequency of library visits showed a dramatic decrease. The use of virtual support to patrons increased during COVID-19 as reflected by the increase in email and chat reference interactions and virtual consultations.Practical implicationsAs students return to the physical classroom, observing library use via various data will help inform how well use of the library rebounded or if there are changes in users' behavior that suggest the need for the promotion of library services or an expansion in alternative services to support users.Originality/valueThis article highlights the importance of continuously obtaining various data sets to observe trends and changes. By observing multiple data points, some changes are aligned across data, whereas other changes or patterns are different. While impact on physical library use may be obvious, library use before and during the pandemic will help guide and inform how academic libraries should be prepared for hybrid environments post-pandemic.

Efficient Designs of Quantum Adder/Subtractor Using Universal Reversible Gate on IBM Q

Reversible arithmetic and logic unit (ALU) is a necessary part of quantum computing. In this work, we present improved designs of reversible half and full addition and subtraction circuits. The proposed designs are based on a universal one type gate (G gate library). The G gate library can generate all possible permutations of the symmetric group. The presented designs are multi-function circuits that are capable of performing additional logical operations. We achieve a reduction in the quantum cost, gate count, number of constant inputs, and delay with zero garbage, compared to relevant results obtained by others. The experimental results using IBM Quantum Experience (IBM Q) illustrate the success probability of the proposed designs.

Quantum key recovery attack on SIMON32/64

The quantum security of lightweight block ciphers is receiving more and more attention. However, the existing quantum attacks on lightweight block ciphers only focused on the quantum exhaustive search, while the quantum attacks combined with classical cryptanalysis methods haven’t been well studied. In this paper, we study quantum key recovery attack on SIMON32/64 using Quantum Amplitude Amplification algorithm in Q1 model. At first, we reanalyze the quantum circuit complexity of quantum exhaustive search on SIMON32/64. We estimate the Clifford gates count more accurately and reduce the T gate count. Also, the T-depth and full depth is reduced due to our minor modifications. Then, using four differentials given by Biryukov in FSE 2014 as our distinguisher, we give our quantum key recovery attack on 19-round SIMON32/64. We treat the two phases of key recovery attack as two QAA instances separately, and the first QAA instance consists of four sub-QAA instances. Then, we design the quantum circuit of these two QAA instances and estimate their corresponding quantum circuit complexity. We conclude that the quantum circuit of our quantum key recovery attack is lower than quantum exhaustive search. Our work firstly studies the quantum dedicated attack on SIMON32/64. And this is the first work to study the complexity of quantum dedicated attacks from the perspective of quantum circuit complexity, which is a more fine-grained analysis of quantum dedicated attacks’ complexity.

Understanding the Impact of Street Patterns on Pedestrian Distribution: A Case Study in Tianjin, China

This paper investigates the impact of street pattern, metro stations, and density of urban functions on pedestrian distribution in Tianjin, China. Thirteen neighborhoods are selected from the city center and suburbs. Pedestrian and vehicle volumes are observed through detailed gate count from 703 street segments in these neighborhoods. Regression models are constructed to analyze the impact of the street pattern, points of interest (POIs), and vehicle and metro accessibility on pedestrian volumes in each neighborhood and across the city. The results show that when analyzing all neighborhoods together, local street connectivity and POIs had a strong influence on pedestrian distribution. Proximity to metro stations and vehicle accessibility had a minor impact. When analyzing each neighborhood separately, both local- and city-scale street patterns affect pedestrian distributions. These findings suggest that the street pattern provides a base layer for metro stations to attract both the emergence of active urban functions and pedestrian movement.

A reversible circuit synthesis algorithm with progressive increase of controls in generalized Toffoli gates

We present a new algorithm for synthesis of reversible circuits for arbitrary n-bit bijective functions. This algorithm uses generalized Toffoli gates, which include positive and negative controls. Our algorithm is divided into two parts. First, we use partially controlled gen- eralized Toffoli gates, progressively increasing the number of controls. Second, exploring the properties of the representation of permutations in disjoint cycles, we apply generalized Toffoli gates with controls on all lines except for the target line. Therefore, new in the method is the fact that the obtained circuits use first low cost gates and consider increasing costs towards the end of the synthesis. In addition, we employ two bidirectional synthesis strategies to improve the gate count, which is the metric used to compare the results obtained by our algorithm with the results presented in the literature. Accordingly, our experimental results consider all 3-bit bijective functions and twenty widely used benchmark functions. The results obtained by our synthesis algorithm are competitive when compared with the best results known in the literature, considering as a complexity metric just the number of gates, as done by alternative best heuristics found in the literature. For example, for all 3-bit bijective functions using generalized Toffoli gates library, we obtained the best so far average count of 5.23.

VLSI Implementation of a Cost-Efficient Loeffler DCT Algorithm with Recursive CORDIC for DCT-Based Encoder

This paper presents a low-cost and high-quality, hardware-oriented, two-dimensional discrete cosine transform (2-D DCT) signal analyzer for image and video encoders. In order to reduce memory requirement and improve image quality, a novel Loeffler DCT based on a coordinate rotation digital computer (CORDIC) technique is proposed. In addition, the proposed algorithm is realized by a recursive CORDIC architecture instead of an unfolded CORDIC architecture with approximated scale factors. In the proposed design, a fully pipelined architecture is developed to efficiently increase operating frequency and throughput, and scale factors are implemented by using four hardware-sharing machines for complexity reduction. Thus, the computational complexity can be decreased significantly with only 0.01 dB loss deviated from the optimal image quality of the Loeffler DCT. Experimental results show that the proposed 2-D DCT spectral analyzer not only achieved a superior average peak signal–noise ratio (PSNR) compared to the previous CORDIC-DCT algorithms but also designed cost-efficient architecture for very large scale integration (VLSI) implementation. The proposed design was realized using a UMC 0.18-μm CMOS process with a synthesized gate count of 8.04 k and core area of 75,100 μm2. Its operating frequency was 100 MHz and power consumption was 4.17 mW. Moreover, this work had at least a 64.1% gate count reduction and saved at least 22.5% in power consumption compared to previous designs.