Hasil untuk "Railroad engineering and operation"

Massimiliano Di Penta, Kelly Blincoe, Marsha Chechik et al.

As software engineering conferences grow in size, rising costs and outdated formats are creating barriers to participation for many researchers. These barriers threaten the inclusivity and global diversity that have contributed to the success of the SE community. Based on survey data, we identify concrete actions the ACM Special Interest Group on Software Engineering (SIGSOFT) can take to address these challenges, including improving transparency around conference funding, experimenting with hybrid poster presentations, and expanding outreach to underrepresented regions. By implementing these changes, SIGSOFT can help ensure the software engineering community remains accessible and welcoming.

Ana B. M. Bett, Thais S. Nepomuceno, Edson OliveiraJr et al.

Context: The empirical software engineering (ESE) community has contributed to improving experimentation over the years. However, there is still a lack of rigor in describing controlled experiments, hindering reproducibility and transparency. Registered Reports (RR) have been discussed in the ESE community to address these issues. A RR registers a study's hypotheses, methods, and/or analyses before execution, involving peer review and potential acceptance before data collection. This helps mitigate problematic practices such as p-hacking, publication bias, and inappropriate post hoc analysis. Objective: This paper presents initial results toward establishing an RR template for Software Engineering controlled experiments using the Open Science Framework (OSF). Method: We analyzed templates of selected OSF RR types in light of documentation guidelines for controlled experiments. Results: The observed lack of rigor motivated our investigation of OSF-based RR types. Our analysis showed that, although one of the RR types aligned with many of the documentation suggestions contained in the guidelines, none of them covered the guidelines comprehensively. The study also highlights limitations in OSF RR template customization. Conclusion: Despite progress in ESE, planning and documenting experiments still lack rigor, compromising reproducibility. Adopting OSF-based RRs is proposed. However, no currently available RR type fully satisfies the guidelines. Establishing RR-specific guidelines for SE is deemed essential.

Hee-Dong Kim, Ja-Young Koo, Jun-Ho Kwak et al.

Martin Obaidi, Marc Herrmann, Jil Klünder et al.

Software development relies heavily on text-based communication, making sentiment analysis a valuable tool for understanding team dynamics and supporting trustworthy AI-driven analytics in requirements engineering. However, existing sentiment analysis tools often perform inconsistently across datasets from different platforms, due to variations in communication style and content. In this study, we analyze linguistic and statistical features of 10 developer communication datasets from five platforms and evaluate the performance of 14 sentiment analysis tools. Based on these results, we propose a mapping approach and questionnaire that recommends suitable sentiment analysis tools for new datasets, using their characteristic features as input. Our results show that dataset characteristics can be leveraged to improve tool selection, as platforms differ substantially in both linguistic and statistical properties. While transformer-based models such as SetFit and RoBERTa consistently achieve strong results, tool effectiveness remains context-dependent. Our approach supports researchers and practitioners in selecting trustworthy tools for sentiment analysis in software engineering, while highlighting the need for ongoing evaluation as communication contexts evolve.

Dehai Zhao, Zhenchang Xing, Qinghua Lu et al.

UI automation is a useful technique for UI testing, bug reproduction, and robotic process automation. Recording user actions with an application assists rapid development of UI automation scripts, but existing recording techniques are intrusive, rely on OS or GUI framework accessibility support, or assume specific app implementations. Reverse engineering user actions from screencasts is non-intrusive, but a key reverse-engineering step is currently missing - recognizing human-understandable structured user actions ([command] [widget] [location]) from action screencasts. To fill the gap, we propose a deep learning-based computer vision model that can recognize 11 commands and 11 widgets, and generate location phrases from action screencasts, through joint learning and multi-task learning. We label a large dataset with 7260 video-action pairs, which record user interactions with Word, Zoom, Firefox, Photoshop, and Windows 10 Settings. Through extensive experiments, we confirm the effectiveness and generality of our model, and demonstrate the usefulness of a screencast-to-action-script tool built upon our model for bug reproduction.

Maarten Vlaswinkel, Duarte Antunes, Frank Willems

Decarbonization of the transport sector sets increasingly strict demands to maximize thermal efficiency and minimize greenhouse gas emissions of Internal Combustion Engines. This has led to complex engines with a surge in the number of corresponding tunable parameters in actuator set points and control settings. Automated calibration is therefore essential to keep development time and costs at acceptable levels. In this work, an innovative self-learning calibration method is presented based on in-cylinder pressure curve shaping. This method combines Principal Component Decomposition with constrained Bayesian Optimization. To realize maximal thermal engine efficiency, the optimization problem aims at minimizing the difference between the actual in-cylinder pressure curve and an Idealized Thermodynamic Cycle. By continuously updating a Gaussian Process Regression model of the pressure's Principal Components weights using measurements of the actual operating conditions, the mean in-cylinder pressure curve as well as its uncertainty bounds are learned. This information drives the optimization of calibration parameters, which are automatically adapted while dealing with the risks and uncertainties associated with operational safety and combustion stability. This data-driven method does not require prior knowledge of the system. The proposed method is successfully demonstrated in simulation using a Reactivity Controlled Compression Ignition engine model. The difference between the Gross Indicated Efficiency of the optimal solution found and the true optimum is 0.017%. For this complex engine, the optimal solution was found after 64.4s, which is relatively fast compared to conventional calibration methods.

Roham Koohestani, Philippe de Bekker, Begüm Koç et al.

Benchmarks are essential for unified evaluation and reproducibility. The rapid rise of Artificial Intelligence for Software Engineering (AI4SE) has produced numerous benchmarks for tasks such as code generation and bug repair. However, this proliferation has led to major challenges: (1) fragmented knowledge across tasks, (2) difficulty in selecting contextually relevant benchmarks, (3) lack of standardization in benchmark creation, and (4) flaws that limit utility. Addressing these requires a dual approach: systematically mapping existing benchmarks for informed selection and defining unified guidelines for robust, adaptable benchmark development. We conduct a review of 247 studies, identifying 273 AI4SE benchmarks since 2014. We categorize them, analyze limitations, and expose gaps in current practices. Building on these insights, we introduce BenchScout, an extensible semantic search tool for locating suitable benchmarks. BenchScout employs automated clustering with contextual embeddings of benchmark-related studies, followed by dimensionality reduction. In a user study with 22 participants, BenchScout achieved usability, effectiveness, and intuitiveness scores of 4.5, 4.0, and 4.1 out of 5. To improve benchmarking standards, we propose BenchFrame, a unified framework for enhancing benchmark quality. Applying BenchFrame to HumanEval yielded HumanEvalNext, featuring corrected errors, improved language conversion, higher test coverage, and greater difficulty. Evaluating 10 state-of-the-art code models on HumanEval, HumanEvalPlus, and HumanEvalNext revealed average pass-at-1 drops of 31.22% and 19.94%, respectively, underscoring the need for continuous benchmark refinement. We further examine BenchFrame's scalability through an agentic pipeline and confirm its generalizability on the MBPP dataset. All review data, user study materials, and enhanced benchmarks are publicly released.

Paloma Guenes, Rafael Tomaz, Bianca Trinkenreich et al.

Research shows that more than half of software professionals experience the Impostor Phenomenon (IP), with a notably higher prevalence among women compared to men. IP can lead to mental health consequences, such as depression and burnout, which can significantly impact personal well-being and software professionals' productivity. This study investigates how IP manifests among software professionals across intersections of gender with race/ethnicity, marital status, number of children, age, and professional experience. Additionally, it examines the well-being of software professionals experiencing IP, providing insights into the interplay between these factors. We analyzed data collected through a theory-driven survey (n = 624) that used validated psychometric instruments to measure IP and well-being in software engineering professionals. We explored the prevalence of IP in the intersections of interest. Additionally, we applied bootstrapping to characterize well-being within our field and statistically tested whether professionals of different genders suffering from IP have lower well-being. The results show that IP occurs more frequently in women and that the prevalence is particularly high among black women as well as among single and childless women. Furthermore, regardless of gender, software engineering professionals suffering from IP have significantly lower well-being. Our findings indicate that effective IP mitigation strategies are needed to improve the well-being of software professionals. Mitigating IP would have particularly positive effects on the well-being of women, who are more frequently affected by IP.

Xingwen Wu, Zhenxian Zhang, Wubin Cai et al.

Purpose – This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie. Design/methodology/approach – Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps. Findings – The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue. Originality/value – The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

WANG Zhonghai, SHI Lei, ZHANG Weige et al.

Capacity decay, performance decline, and other degradations experienced by lithium-rich silicon/carbon pouch batteries during repeated charging and discharging processes are collectively called cyclic failures. These failures prevent the batteries from meeting long-term usage requirements. This study aims to effectively address these deficiencies. First, experiments were conducted on Ah-rated full batteries assembled with Li-rich manganese-based positive electrode materials and silicon/carbon negative electrode materials to examine their electrochemical properties. Second, batteries subjected to cycling were disassembled for various testing analyses to investigate the failure process of high-specific-energy Li-rich Si/C pouch batteries. The research results identify three main reasons for the capacity degradation of Ah-rated full batteries: lithium loss, electrochemical polarization, and structural damage to the negative electrode. Batteries disassembled after less than 50 cycles show slight changes in the structure of their positive and negative electrodes, as well as in elements revealed by ICP testing. This suggests that the capacity decay of these full batteries during the first 50 cycles is mainly caused by lithium loss and electrochemical polarization. Beyond 50 cycles, the capacity of the positive electrode materials decreased by 8%, while that of the negative electrode materials decreased by 70%. This indicates that, beyond this point, capacity decay in these full batteries is mainly caused by structural damage to their negative electrodes.

Jialiang Wei, Anne-Lise Courbis, Thomas Lambolais et al.

Graphical User Interfaces (GUIs) are central to app development projects. App developers may use the GUIs of other apps as a means of requirements refinement and rapid prototyping or as a source of inspiration for designing and improving their own apps. Recent research has thus suggested retrieving relevant GUI designs that match a certain text query from screenshot datasets acquired through crowdsourced or automated exploration of GUIs. However, such text-to-GUI retrieval approaches only leverage the textual information of the GUI elements, neglecting visual information such as icons or background images. In addition, retrieved screenshots are not steered by app developers and lack app features that require particular input data. To overcome these limitations, this paper proposes GUing, a GUI search engine based on a vision-language model called GUIClip, which we trained specifically for the problem of designing app GUIs. For this, we first collected from Google Play app introduction images which display the most representative screenshots and are often captioned (i.e.~labelled) by app vendors. Then, we developed an automated pipeline to classify, crop, and extract the captions from these images. This resulted in a large dataset which we share with this paper: including 303k app screenshots, out of which 135k have captions. We used this dataset to train a novel vision-language model, which is, to the best of our knowledge, the first of its kind for GUI retrieval. We evaluated our approach on various datasets from related work and in a manual experiment. The results demonstrate that our model outperforms previous approaches in text-to-GUI retrieval achieving a Recall@10 of up to 0.69 and a HIT@10 of 0.91. We also explored the performance of GUIClip for other GUI tasks including GUI classification and sketch-to-GUI retrieval with encouraging results.

Marvin Wyrich, Marvin Muñoz Barón, Justus Bogner

Software engineering (SE) is full of abstract concepts that are crucial for both researchers and practitioners, such as programming experience, team productivity, code comprehension, and system security. Secondary studies aimed at summarizing research on the influences and consequences of such concepts would therefore be of great value. However, the inability to measure abstract concepts directly poses a challenge for secondary studies: primary studies in SE can operationalize such concepts in many ways. Standardized measurement instruments are rarely available, and even if they are, many researchers do not use them or do not even provide a definition for the studied concept. SE researchers conducting secondary studies therefore have to decide a) which primary studies intended to measure the same construct, and b) how to compare and aggregate vastly different measurements for the same construct. In this experience report, we discuss the challenge of study selection in SE secondary research on latent variables. We report on two instances where we found it particularly challenging to decide which primary studies should be included for comparison and synthesis, so as not to end up comparing apples with oranges. Our report aims to spark a conversation about developing strategies to address this issue systematically and pave the way for more efficient and rigorous secondary studies in software engineering.

M. Girardi, Ó. Helgason, A. Caut et al.

Silicon nitride is an excellent material platform for its extremely low loss in a large wavelength range, which makes it ideal for the linear processing of optical signals on a chip. Moreover, the Kerr nonlinearity and the lack of two-photon absorption in the near infrared enable efficient nonlinear optics, e.g., frequency comb generation. However, linear and nonlinear operations require distinct engineering of the waveguide core geometry, resulting in a tradeoff between optical loss and single-mode behavior, which hinders the development of high-performance, ultralow-loss linear processing blocks on a single layer. Here, we demonstrate a dual-layer photonic integration approach with two silicon-nitride platforms exhibiting ultralow optical losses, i.e., a few dB/m, and individually optimized to perform either nonlinear or linear processing tasks. We demonstrate the functionality of this approach by integrating a power-efficient microcomb with an arrayed waveguide grating demultiplexer to filter a few frequency comb lines in the same monolithically integrated chip. This approach can significantly improve the integration of linear and nonlinear optical elements on a chip and opens the way to the development of fully integrated processing of Kerr nonlinear sources.

O. Strelko

The history of bridge construction is an important part of historical knowledge. Developments in bridge construction technology reflect not only engineering advances, but also social, economic and cultural aspects of society. Engineers and scientists faced unique challenges when designing and building bridges depending on the technological level of the era, available materials and the needs of society. This process may reflect technological progress, changes in transportation needs, and cultural and social changes. The purpose of this article is to briefly review key moments and stages in the history of metal bridge construction using welding technology in the 20th century. The history of the development of the construction of metal bridges using welding goes back a little over 100 years. The short period from the construction of the first welded bridges to their first disasters led to the need to analyze the possible causes of these destructions. As the analysis performed showed, catastrophic destruction most often occurred under the influence of several factors, as well as a combination of external adverse influences and the internal “unpreparedness” of the structure for them. The above examples indicate that an irrational choice of steel could be both an independent cause causing brittle failure of structures, and an aggravating factor in the presence of structural violations, thermal stresses and welding defects. Over the years, bridge manufacturing technologies have been improved in different countries, and new steels and materials for their welding have been developed. Thanks to the use of carbon, low-alloy and alloy steel, designers abandoned the brutal “railroad-type” beam trusses and today metal bridges with graceful and beautiful silhouettes powerfully stride across the water surface, mountains and valleys. They became real attractions of megacities and country landscapes, and builders were able to successfully solve numerous technical and economic problems. An important contribution to the development of global bridge construction using welding technologies was made by the team of the Institute of Electric Welding of the Academy of Sciences of the Ukrainian SSR under the leadership of Academician Evgeny Oskarovych Paton. The team of the Institute of Electric Welding of the Academy of Sciences of the Ukrainian SSR, introducing welding into bridge construction, carefully checked the results and monitored the behavior of structures. A new grade of steel was created that was resistant to the formation of brittle and fatigue cracks, its welding technology was developed, a technology for installation welding of vertical sheets with forced formation of a seam was developed, and suitable welding materials were selected. At the time of construction in 1953, the Kyiv Evgeny Paton Bridge across the Dnipro River was the largest all-welded bridge in Europe, all seams of which, including assembly ones, were made for the first time using automatic and semi-automatic welding. In addition, the presence of large similar blocks in the design of the Evgeny Paton Bridge made it possible to mechanize assembly and welding operations and organize an in-line method for their production at the factory and installation, which improved the quality of welding work and reduced its labor intensity.

Yuan Zhang, Wei Wei, Boyang Liu et al.

Abstract The 20,000-ton combined train running has greatly promoted China’s heavy-haul railway transportation capability. The application of controllable train-tail devices could improve the braking wave of the train and braking synchronism, and alleviate longitudinal impulse. However, the characteristics of the controllable train-tail device such as exhaust area, exhaust duration and exhaust action time are not uniform in practice, and their effects on the longitudinal impulse of the train are not apparent, which is worth studying. In this work, according to the formation of the Datong–Qinhuangdao Railway, the train air brake and longitudinal dynamics simulation system (TABLDSS) is applied to establish a 20,000-ton combined train model with the controllable train-tail device, and the braking characteristics and the longitudinal impulse of the train are calculated synchronously with changing the air exhaust time, exhaust area, and action lag time under initial braking. The results show that the maximum coupler force of the combined train will decrease with the extension of the continuous exhaust time, while the total exhaust time of the controllable train-tail device remains unchanged; the maximum coupler force of the combined train reduces by 32.5% with the exhaust area increasing from 70% to 140%; when the lag time between the controllable train-tail device and the master locomotive is more than 1.5 s, the maximum coupler force of the train increases along with the time difference enlargement.

WANG Yanping

The paper provided a brief introduction to the characteristics and current applications of permanent magnet synchronous motors in the trains of Changsha metro line 5. It selected an experimental train that used a permanent magnet synchronous traction system on Changsha metro line 1 to conduct line simulation and on-site energy-saving tests for the traction system's energy consumption. Based on the analysis of the no-load energy consumption of trains using asynchronous traction systems on lines 1–4 and trains using permanent magnet synchronous traction systems on line 5 of Changsha metro, the efficiency and energy consumption with trains using asynchronous traction systems were compared and analyzed in detail. It was found that for the lines with regenerative energy absorption and utilization devices installed on the overhead contact network of the main track, excluding the impact of passenger capacity, the average energy saving rate of no-load trains on line 5 was 29.56% compared to line 1, line 3, and line 4, and 39.21% compared to line 2 without the regenerative energy absorption and utilization devices installed on the overhead contact network of the main track. Energy consumption of the train is an important part of the operation cost. The permanent magnet traction system has obvious energy-saving effect, which is consistent with the national requirements for the development of energy-saving, low-carbon economy. The application of permanent magnet traction system is helpful to reduce the operating cost of metro trains and realize the goal of rapid green transportation.

Zhiyu Fan, Yannic Noller, Ashish Dandekar et al.

The growing number of students enrolling in Computer Science (CS) programmes is pushing CS educators to their limits. This poses significant challenges to computing education, particularly the teaching of introductory programming and advanced software engineering (SE) courses. First-year programming courses often face overwhelming enrollments, including interdisciplinary students who are not CS majors. The high teacher-to-student ratio makes it challenging to provide timely and high-quality feedback. Meanwhile, software engineering education comes with inherent difficulties like acquiring industry partners and the dilemma that such software projects are often under or over-specified and one-time efforts within one team or one course. To address these challenges, we designed a novel foundational SE course. This SE course envisions building a full-fledged Intelligent Tutoring System (ITS) of Programming Assignments to provide automated, real-time feedback for novice students in programming courses over multiple years. Each year, SE students contribute to specific short-running SE projects that improve the existing ITS implementation, while at the same time, we can deploy the ITS for usage by students for learning programming. This project setup builds awareness among SE students about their contribution to a "to-be-deployed" software project. In this multi-year teaching effort, we have incrementally built an ITS that is now deployed in various programming courses. This paper discusses the Intelligent Tutoring System architecture, our teaching concept in the SE course, our experience with the built ITS, and our view of future computing education.

Wen Wang, Xin Zhang, Xiaoning Liu

To reduce urban pressure, urban rail transit has become an effective way to reduce traffic congestion, mitigate traffic accidents, reduce environmental pollution, and improve commuting efficiency. Subway as the main means of urban public transport travel, in recent years by people’s favor, although the construction industry of rail transit is developing rapidly and the industry scale is expanding, but because the construction of rail transit construction projects is very difficult, especially in the wet loess within the concealed excavation tunnel, but also frequent accidents, and the quality of the project is not easy to guarantee, so the underground railroad wet loess within the concealed excavation tunnel construction technology is poor. Therefore, it is especially important to study the construction technology and project quality management of underground railway concealed tunnel in wet loess. In this paper, based on the in-depth study of the basic principle of quantum particle swarm optimization calculation and the realization of key engineering technologies, the particle swarm optimization algorithm is programed using MATLAB software, and the coding scheme, operation specification, and operation parameters are designed. Then, combined with the particle swarm optimization algorithm and assisted MATLAB software, the main analysis of the construction and quality control of wet loess in concealed tunnels of subway projects was carried out, mainly by systematizing the relationship between the three major elements of subway project schedule, cost, and management and the construction and quality control of wet loess in concealed tunnels of a subway, and concluded that the construction and quality control of wet loess in concealed tunnels of the subway needed schedule. It is concluded that the construction and quality control of subway wet loess tunnel requires stable schedule, adequate cost budget, and management personnel.

Pavel Svanda

V práci jsou ukázány dva netypické případy korozního praskání železných slitin. Korozivzdorná austenitická ocel 1.4404 (ASTM 316L) byla vystavena působení spalných plynů po spalování práškového uhlí ve fluidním kotli. Koroze byla iniciována zbytkovým pnutím po tváření za studena. Ocel 1.2343 byla použita na výrobu formy pro tlakové lití hliníku. Zde byla koroze iniciována na povrchu chladicího kanálu. V chladicím okruhu byla používána upravená voda s inhibitory koroze o pH 8 až 9. V obou případech nebyla zjištěna žádná kontaminace povrchu či nehomogenita složení materiálu, která by vysvětlovala možné příčiny koroze. Navíc byl rozvoj korozních trhlin velmi rychlý. Vzhledem k tomu, že v obou případech došlo k iniciaci v místech výrazným napětím v materiálu, lze oprávněně předpokládat poškození právě mechanismem korozního praskání.

Ian A. Cosden, Kenton McHenry, Daniel S. Katz

As software has become more essential to research across disciplines, and as the recognition of this fact has grown, the importance of professionalizing the development and maintenance of this software has also increased. The community of software professionals who work on this software have come together under the title Research Software Engineer (RSE) over the last decade. This has led to the formalization of RSE roles and organized RSE groups in universities, national labs, and industry. This, in turn, has created the need to understand how RSEs come into this profession and into these groups, how to further promote this career path to potential members, as well as the need to understand what training gaps need to be filled for RSEs coming from different entry points. We have categorized three main classifications of entry paths into the RSE profession and identified key elements, both advantages and disadvantages, that should be acknowledged and addressed by the broader research community in order to attract and retain a talented and diverse pool of future RSEs.