bluuebunny/crossref_metadata_2025 huggingface dataset:
Kecerdasan Buatan berbasis Geospasial (GeoAI) menggunakan Google Earth Engine untuk Monitoring Fenomena Urban Heat Island di Indonesia
Authors: DARMAWAN SONI , NURULHAKIM NADA NAFISYAH , HERNAWATI RIKA
Published: April 2024

ABSTRAKFenomena Urban Heat Island (UHI) sangat penting untuk dimonitor agar terjaga kualitas lingkungan perkotaan. Dewasa ini teknologi kecerdasan buatan berbasis geospasial (GeoAI) merupakan teknologi yang menjanjikan untuk mengidentifikasi dan monitoring secara cepat dan efisien suatu kawasan yang luas. Walaupun Kecerdasan buatan sudah banyak diteliti namun GeoAI untuk identifikasi dan monitoring fenomena UHI di Indonesia masih terbatas. Penelitian ini bertujuan untuk membangun sistem GeoAI menggunakan google earth engine untuk monitoring fenomena UHI di Indonesia. Metodologi pada penelitian ini dimulai dari perancangan sistem, penghimpunan data dan komputasi, pembuatan dashboard, pengujian, hingga visualisasi UHI di Indonesia. Hasil penelitian ini berupa sistem aplikasi untuk monitoring fenomena UHI di Indonesia yang divisualisasikan dalam sebuah dashboard menggunakan Earth Engine Apps yang dapat diakses pada tautan https://bit.ly/UHIGDItenas.Kata kunci: Kecerdasan buatan, Penginderaan jauh dan Geospasial ABSTRACTUrban Heat Island (UHI) phenomenon is very important to monitor for managing the quality of the urban environment. Recently geospatial-based artificial intelligence (GeoAI) technology is a promising technology for quickly and efficiently identifying and monitoring on the large area. Even though artificial intelligence has been widely researched, GeoAI for identifying and monitoring the UHI phenomenon in Indonesia is still limited. This research aims to build a GeoAI system using the Google Earth engine for monitoring the UHI phenomenon in Indonesia. The methodology in this research starts from system design, data collection and computing, dashboard creation, testing and visualization of UHI in Indonesia. The results of this research are an application system for monitoring the UHI phenomenon in Indonesia which is visualized in a dashboard using Earth Engine Apps which can be accessed on https://bit.ly/UHIGDItenas.Keywords: Artificial Intelligence, Remote sensing, and Geospatial
Sistem Pembangkit Listrik Tenaga Surya (PLTS) menggunakan Teknologi Maximum Power Point Tracking (MPPT) dan Zeta Converter
Authors: HARAHAP PARTAONAN , RITONGA RAHMAT , RIMBAWATI RIMBAWATI , OKTRIALDI BENNY , SIREGAR MUNAWAR ALFANSURY , LUBIS SUDIRMAN , SIREGAR CHANDRA A
Published: April 2024

ABSTRAKSistem kendali MPPT hendak mengendalikan penciptaan serta penyimpanan energi sistem PV menggunakan DC-DC boost converter. Perancangan dan pembuatan alat zeta converter berhasil dilakukan dengan menggunakan mikrokontroller arduino untuk menaikkan tingkat effisiensi daya keluaran pada PLTS berhasil dilakukan dengan baik. Keluaran tegangan serta arus yang dihasilkan oleh MPPT dengan memakai zeta converter relatif efektif dan effisien dibuktikan dengan daya keluaran PLTS yang memiliki tingkat effisiensi yang stabil setiap pengambilan data, dan tingkat effisiensi yang dihasilkan juga relatif tinggi yaitu 92%. Perhitungan yang dilakukan adalah dengan cara mengambil data arus dan tegangan pada MPPT tanpa zeta converter dan dengan zeta converter yang telah dihitung melalui perhitungan duty cycle. Adapun nilai duty cycle yang dihasilkan adalah 0,243 atau 24% dan arus input maximal yang dihasilkan setelah perhitungan adalah 5,34 Ampere.Kata Kunci: PLTS, MPPT, Zeta Converter, Arduino ABSTRACTUsing a DC-DC boost converter, the MPPT management system will manage the generation and storage of PV system energy. The zeta converter was designed and manufactured successfully utilizing an Arduino microcontroller to boost the efficiency level of output power in PLTS. The voltage and current output produced by MPPT utilizing a zeta converter is relatively effective and efficient. The voltage and current output produced by MPPT using a zeta converter is relatively effective and efficient, as proven by the PLTS output power which has a stable efficiency level every time data is taken, and the resulting efficiency level is also relatively high, namely 92%. The calculations carried out are by taking current and voltage data on the MPPT without a zeta converter and with a zeta converter which has been calculated through duty cycle calculations. Meanwhile, the resulting duty cycle value is 0.243 or 24% and the maximum input current produced after calculation is 5.34 Amperes.Keywords: PLTS, MPPT, Zeta Converter, Arduino
Identifikasi Emosi Melalui Sinyal EEG menggunakan 3D-Convolutional Neural Network
Authors: SENJAWATI RINDU TEGAR , DJAMAL ESMERALDA CONTESSA , KASYIDI FATAN
Published: April 2024

ABSTRAKEmosi memberikan peran penting dalam interaksi manusia yang didapat melalui respon yang tepat. Respon yang tak tepat menunjukan adanya gangguan mental sehingga diperlukan identifikasi emosi. Identifikasi dapat dilakukan menggunakan aktivitas sinyal listrik di otak menggunakan Elektroensephalogram (EEG). Karena sinyal EEG pada setiap kanal merupakan urutan data maka dijadikan multi-kanal yang direpresentasikan pada matriks agar urutan-urutan data tetap terjaga. Penggunaan matriks memadukan informasi dari ketiga dimensi (kanal x frekuensi x waktu) dapat menggambarkan kompleksitas dari sinyal EEG. Sehingga dapat mengenali pola aktivitas otak pada rentang frekuensi tertentu berkembang sepanjang waktu. Untuk menangkap informasi tersebut perlu dilakukan ekstraksi fitur agar mewakili variabel-variabel emosi. Ekstraksi dilakukan pada domain frekuensi (4-45 Hz) dan waktu menggunakan Short Time Fourier Transform (STFT) kemudian idenitifikasi menggunakan 3D Convolutional Neural Network (CNN). Eksperimen menggunakan 3D CNN menghasilkan akurasi 65.45 dengan teknik koreksi bobot Adamax.Kata kunci: emosi, sinyal EEG, multi-kanal, STFT, 3D-CNN ABSTRACTEmotions play an important role in human interaction through appropriate responses. Inappropriate responses indicate a mental disorder, so identification of emotions is required. Identification can be done using electrical signal activity in the brain with Electroencephalogram (EEG). Because the EEG signal in each channel is a data sequence, it is made into a multi-channel represented in a matrix so that the data sequence is maintained. Using a matrix combining information from all three dimensions (channel x frequency x time) can describe the complexity of the EEG signal. Allowing recognition of evolving brain activity patterns within specific frequency ranges over time. Extraction is done in the frequency domain (4-45 Hz) and time using Short Time Fourier Transform (STFT), then identification using a 3D Convolutional Neural Network (CNN). Experiments using 3D CNN resulted in an accuracy of 65.45 with the Adamax weight correction technique.Keywords: emotion, EEG signal, multi-channel, STFT, 3D-CNN
Sistem Otomatisasi Tong Sampah dengan Pemanfaatan Solar Panel berbasis Arduino
Authors: SUTISNA NUUR SHOFIYAH , ANWAR MISITA , MUSTAFA MAHMUD , IDRIS MUHAMMAD MA’RUF , SAHARUDDIN SAHARUDDIN
Published: April 2024

ABSTRAKPenelitian ini membahas mengenai rancang bangun sebuah sistem inovatif yang mengotomatisasi proses membuka dan menutup tong sampah dengan memanfaatkan panel surya dan platform Arduino. Penlitian ini dilatar belakangi oleh rasa malas untuk membuang sampah karena harus bersentuhan langsung dengan tong sampah. Alat ini dirancang untuk meningkatkan efisiensi pengelolaan sampah, mengurangi kontaminasi silang, serta mengurangi interaksi manusia dengan permukaan tong sampah. Penelitian ini memaparkan tahap desain, pengembangan, dan implementasi alat otomatis yang melibatkan perakitan perangkat keras, pengaturan program, dan instalasi sistem. Hasil penelitian menunjukkan bahwa alat ini mampu membuka dan menutup tong sampah secara andal dengan tingkat keberhasilan lebih dari 95% dalam berbagai kondisi cuaca.Kata kunci: panel surya, arduino, tong sampah ABSTRACTThis research discusses the design of an innovative system that automates the process of opening and closing trash bins using solar panels and the arduino platform. The study is motivated by the reluctance to dispose of garbage due to the need for direct contact with the trash bin. The device is designed to improve waste management efficiency, reduce cross-contamination, and minimize human interaction with the trash bin's surface. The research presents the stages of hardware assembly, program configuration, and system installation for the automatic device. The research results demonstrate that the device reliably opens and closes the trash bin with a success rate of over 95% under various weather conditions.Keywords: solar panels, arduino, trash bins
Optimasi Economic Emission Dispatch menggunakan Whale Optimization Algorithm untuk Penentuan Biaya Reduksi Emisi
Authors: MUFLIKHAH INTAN LAILY , RAHARJO JANGKUNG , SASTROSUBROTO ASHWIN SASONGKO
Published: April 2024

ABSTRAKPembangkit Listrik Tenaga Uap Batu bara menghasilkan zat SO2, CO2, NO2, dan partikel yang merupakan emisi dari proses pembakarannya. Emisi tersebut menyebabkan peningkatan efek pemanasan global, kerusakan lingkungan, dan merusak kesehatan. Dikarenakan pembangkit batu bara masih banyak digunakan di Indonesia maka Economic Emission Dispatch yang dikombinasikan dengan algoritma Whale Optimization Algorithm menjadi solusi dalam pengurangan emisi pembangkit listrik. Dengan cara memasukkan nilai weighted sum pada fungsi biaya dan emisi agar dapat dilihat pembangkit mana yang memiliki kadar emisi lebih rendah untuk memenuhi beban listrik yang dibutuhkan. Pada simulasi tersebut didapatkan pengurangan kadar emisi sebesar 12,73% dibandingkan tanpa menggunakan weighted sum dengan algortima WOA. Hal ini mampu untuk membantu program pemerintah dalam mengurangi emisi karbon agar tidak melebihi standar emisi yang telah ditetapkan sesuai dengan Peraturan Menteri Nomor P.15/MENLHK/SETJEN/KUM.1/4/2019.Kata kunci: PLTU batu bara, emisi, EED, WOA, weighted sum ABSTRACTCoal-fired power plants produce SO2, CO2, NO2, and particulate matter as emissions from the combustion process. These emissions cause increased global warming effects, environmental damage, and damage to health. coal plants are still widely used in Indonesia, Economic Emission Dispatch combined with the Whale Optimization Algorithm is a solution for reducing power plant emissions. By entering the weighted sum value in the cost and emission functions, it can be seen which plants have lower emission levels to meet the required electricity load. The simulation obtained a reduction in emission levels of 12.73% compared to not using weighted sum with the WOA algorithm. This method is able to help government programs in reducing carbon emissions so as not to exceed the emission standards that have been set in accordance with Peraturan Menteri Nomor P.15/MENLHK/SETJEN/ KUM.1/4/2019.Keywords: coal power plant, emission, EED, WOA, weighted sum
El abordaje de la Agenda 2030 en el programa de Licenciatura en Bilingüismo con énfasis en Español e Inglés de la Institución Universitaria Colombo Americana- ÚNICA durante 2023-II. Una Sistematización de las iniciativas implementadas en materia de Agenda 2030 y Objetivos de Desarrollo Sostenible (ODS)
Authors: Amézquita Quintana Constanza
Published: April 2024

Este working paper se enfoca en el abordaje de la Agenda 2030 y los ODS en el programa de Licenciatura en Bilingüismo con énfasis en Español e Inglés de la Institución Universitaria Colombo Americana- ÚNICA durante el segundo semestre del año 2023, a través de la sistematización de las iniciativas en materia de Agenda 2030 implementadas en dicho programa durante el período en mención. Este Working paper es resultado del proyecto de investigación titulado “Sistematización de la transversalización de la Agenda 2030 y los ODS en la Institución Universitaria Colombo Americana – ÚNICA mediante el programa ‘ÚNICA al servicio de los ODS’” llevado a cabo en 2023 por la autora. Se recopilaron y sistematizaron las iniciativas en materia de Agenda 2030 creadas por los docentes de la licenciatura en 2023-II, teniendo en cuenta: (1) el número de iniciativas desarrolladas en el semestre, (2) el número de asignaturas que implementaron estas iniciativas, (3) el abordaje de uno o varios ODS en dichas iniciativas, (4) los ODS implementados, (5) las competencias transversales para la sostenibilidad promovidas, y (6) las estrategias didácticas empleadas.
СТРУКТУРНЫЕ ОСОБЕННОСТИ ЛЮМИНОФОРОВ НА ОСНОВЕ СТРОНЦИОВИТЛОКИТА
Authors: Никифоров И.В. , Титков В.В. , Аксенов С.М. , Лазоряк Б.И. , Барышникова О.В. , Дейнеко Д.В.
Published: April 2024

Получены новые фосфаты Sr8(Zn1–xMnx)La(PO4)7 методом твердофазного синтеза. Показано, что образуется непрерывная серия твердых растворов. Все синтезированные вещества кристаллизуются в структурном типе стронциовитлокита с пространственной группой R-3m. Методом Ритвельда уточнены структурные параметры. Изучены люминесцентные свойства и установлена связь с особенностями кристаллической структурны. Образцы обладают стабильной люминесценцией в красно-оранжевой области. Наибольшей интенсивностью фотолюминесценции обладает образец с х = 0.5.
The effect of horizontal loads caused by rapidly rising river water on the bearing capacity of masonry arch bridges
Authors: Van Bogaert Philippe , De Backer Hans
Published: April 2024

Many masonry arch bridges have a culturally significant history, as well as aesthetic appeal, as the arch shape adds to a balanced appearance. Some of these arch bridges are crossing rivers, which have fast rising torrent water, especially after winter. The bridge piers are then exposed to horizontal loads from wave impact and debris. These loads can occur several times a year and are therefore not accidental. Numerical simulations of the case of Devil’s Bridge (Bulgaria) demonstrate that nonlinear FE-analysis, on the basis of Mohr-Coulomb’s law, is not entirely fit for this type of structure. Determining the shear strength, after cracking is inaccurate, because of the material’s brittle character. The torrent wave causes such kind of failure, whereas first the debris impact causes local damage, the latter fostering the failure. Therefore, maintenance of stones and joints of such bridges is of capital importance.
Masonry arch bridges in the 21st century
Authors: Gilbert Matthew , Smith Colin , Amodio Serena
Published: April 2024

Masonry arch bridges have proved to be resilient, long-lasting structures, and continue to form a crucial part of the railway and regional highway networks of the UK and many other countries. Given this, and the comparatively low embodied carbon associated with natural stone as a building material, the masonry arch form looks set to once again become attractive to designers. However, some aspects of their behaviour remain poorly understood. This can unfortunately lead to existing bridges being needlessly strengthened (or even demolished and replaced), or, alternatively, being subjected to loading regimes that cause long-term damage. In this contribution key elements of the recently published CIRIA C800 guidance on the assessment of masonry arch bridges are highlighted, including how the presented advice may in future be applied in the design of new bridges.
Construction and Testing of a CFRP-prestressed Railway Bridge Prototype
Authors: Näsbom Andreas , Thoma Karel , Kaufmann Walter
Published: April 2024

This paper presents a new single-span railway bridge system, currently under development by the authors in cooperation with the Swiss Federal Railways and further partners, combining high- performance concrete, stainless reinforcing steel and CFRP prestressing for maximum durability. A significant milestone in the project was the successful construction and testing of a 6,5 x 1,7 m2 prototype consisting of four pretensioned longitudinal girders; each prestressed with 12 Ø8,2 mm sand-coated CFRP rods. The paper discusses selected aspects of the sustainability of the novel material combination and the construction of the prototype. Furthermore, the structural behaviour of the prototype is analysed, focusing on its response under shear forces.
Shifting the Density Discourse: The Future of Soft Density
Authors: Lavoie Audrey-Frédérique , Galopoulou Kely , Tekbas Zehra Lara
Published: April 2024

This study by UCL Sustainability Lab, Mott MacDonald, and the ΙStructE explores the factors influencing the sustainability of the built environment in its urban ecosystem. The research extends beyond structural engineering to a holistic view of sustainable urban development. With more than half of the global population living in urban areas, effective sustainable urban densification strategies must be deployed to address multiple climate and housing challenges. This project aims to bridge disciplinary gaps in the built environment sector, identify characteristics of sustainable urban ecosystems, and establish a guide for integrating urban development with sustainability. Focusing on transportation, green spaces, and carbon emissions, the research suggests soft-density strategies as optimal, highlighting the necessity of a multidisciplinary, collaborative approach that avoids one-size-fits-all solutions.
Nonlinear Creep Analysis of Long-span Prestressed Concrete Bridges
Authors: Wu Shiyu , Liu Zhao , Tong Teng
Published: April 2024

Long-span prestressed concrete (PC) bridges tend to have larger deflection than code-based estimation after several years of operation. Even though creep is usually blamed as one of the most influential time-dependent factors, most current creep models do not give sufficient attention to nonlinear creep behaviour due to higher compressive working stress. In this study, a nonlinear creep model characterized by a stress-sensitive amplification factor is proposed based on experimental data from literature. The model is embedded into the rate-type formula using several user subroutines in Abaqus. Furthermore, a computational framework is established which involves the intertwined effects of concrete creep, shrinkage, and the influence of steel strands relaxation. Finally, a long-span rigid frame box girder bridge is analysed resulting in a good estimation with the in-situ measurement in terms of the long-term deflection.
Fatigue life prediction of orthotropic steel decks based on Phase Field model
Authors: Xiong Zhihua , Liu Xuyao , Di Di , Rittich Nils , Feldmann Markus
Published: April 2024

The Orthotropic Steel Deck (OSD) is prone to fatigue crack due to initial defects caused by welding and the cyclic loading. Instead of sharp crack path tracking in OSD fatigue crack failure modeling, Phase Field (PF) approach uses diffuse damage localization, which has been adopted in simulating the crack propagation in OSD. The Nominal Stress method was used to simplify the OSD into a two- dimensional model, and the initial defects and residual stresses were incorporated in the model. Based on the PF model, the remaining fatigue life of typical welded details in an OSD was predicted. An Ultra High-Performance Concrete (UHPC) strengthening technique was presented, and the schemes before and post strengthened were compared under the same test conditions. The results show that the PF model is efficient in assessing the remaining fatigue life of OSD, and the fatigue life of OSD can be improved by this strengthening scheme.
Microcracks assessment during unloading for structural elements reuse
Authors: Sunayana Sushree , Ottosen Lisbeth M.
Published: April 2024

Larger scale concrete production to satisfy rapid infrastructural development leads to significant resource exploitation. One of the important ways to achieve sustainability in concrete construction is by optimizing the use of resources. To address this challenge, reusing structural concrete elements emerges as a viable alternative. During the process of selective demolition, structural concrete elements are unloaded. To assess their quality for reuse, a non-destructive testing technique is required. This study investigates the propagation of surface cracking during loading and unloading states using a digital image correlation (DIC) technique. Standard concrete prism specimens were subjected to compression loading at different stress levels before reaching the peak stress and subsequently unloaded. A novel method was developed to analyze the microcracks during unloading by digitally reproducing the DIC data. Quantification of surface cracking in the unloaded state can provide insights into the previous stress state experienced by the concrete elements and potential areas for reuse.
Evaluation on a load-carrying capacity of the stiffened plates subjected to biaxial forces considering the local buckling of the longitudinal ribs
Authors: Yasuda Kousuke , Yamaguchi Takashi , Osakabe Seiji
Published: April 2024

This study analyzed load-carrying capacity of stiffened plates under one and two-directional forces with variations in the rib arrangement and the ratio of applied vertical to horizontal stress. The analysis was based on the Metropolitan Expressway Company's standard drawings for Steel Deck Structures. In the case that subjected to uniform compression along the bridge axis, reducing the number of longitudinal ribs from 8 to 6 increased the width-to-thickness ratio parameter from 0.54 to 0.70, with little impact on the obtained load-carrying capacity. On the other hand, the case under uniform compression perpendicular to the bridge axis, reducing ribs resulted in decrease of load- carrying capacity. In the case that subjected to biaxial forces, the load-carrying capacity curves depend on the width-to-thickness ratio parameters of each direction, and it demonstrated the difference buckling resistance of the ribs.
A low carbon bridge over the River Thames, London, UK
Authors: Liaghat Davood , Nip Koon Lok (Stephen) , Chatzidaki Antigoni , Osborne Tom , Latxague Enea
Published: April 2024

The construction industry must make a concerted effort to reduce its carbon footprint. This initiative for carbon reduction should supplement the social and economic benefits that infrastructure projects offer. A proposition project was initiated to design a pedestrian and cycle bridge over the River Thames in London with a carbon target of 250 kgCO2e/m2, whilst not compromising the functionality of the bridge. To this end, the Nine Elms to Pimlico site, in London, was chosen as our challenge. The project has shown that a low carbon bridge over the river is feasible, although achieving an upfront carbon of less than 250 kgCO2e/m2 proved to be too ambitious for this bridge with current design constraints. The need for unconventional materials, technologies and design processes has been identified. A reduction of 75% was achieved by redesigning the superstructure, to reach the targeted carbon further work is needed on the substructure and foundations.
River Lea Crossing Refurbishment & Strengthening: A case study for refurbishment of an historic bridge
Authors: Duvall Michael , Hodgkinson Andrew
Published: April 2024

The River Lea Crossing was completed in 1934 and remains in service today, carrying the A13 in East London over a tributary to the River Thames. The crossing comprises a single two-pinned arch span of approximately 61m. The bridge is constructed of steel and is supported on huge mass concrete abutments. Due to the expectations that it was nearing the end of its service life the was planned to be replaced by 2030. An extensive programme of surveys, inspection, monitoring and assessment of the superstructure and substructure, going beyond the normal requirements of current inspection and assessment standards, demonstrated that the bridge could be retained and refurbished to considerably extend its serviceable life.

This paper presents a case study of the project providing an example for future bridge rehabilitation schemes, which will inevitably become more prevalent as the industry learns to make better use of existing assets and build less in response to the Climate Emergency.
Numerical Study on Square Large Sectional Concrete-Filled Steel Tubular Columns with Separating Cross Steel Plate
Authors: Li Wencong
Published: April 2024

To meet the demand of structural performance of the tomorrow’s supertall buildings, square large sectional concrete-filled steel tubular columns with separating cross steel plate were proposed. In this research, numerical studies on the square large sectional concrete-filled steel tubular columns with separating cross steel plate under lateral force in two different directions are carried out to investigate the effect of loading direction on the inelastic behavior of this kind of column. Numerical results show that there is no significant difference in the initial flexural stiffnesses of the proposed square large sectional concrete-filled steel tubular columns with separating cross steel plate in two different loading directions, but there is a certain degree of difference in their flexural strengths.
Extradosed Bridge Part of the Third Ring Road of Mecca – Conceptual Design
Authors: Sima Fernando , Schlaich Mike , Youakim Maher , Ayoub Essam , Hany Karim , Bakhoum Mourad
Published: April 2024

The aim of this paper is to present the conceptual design process of the proposed Extradosed Bridge, as part of the Third Ring Road of Mecca project, near the Jamarat site in KSA. The proposed bridge is conceived as an Extradosed Bridge with an open cross section with two main longitudinal girders in post tensioned concrete and spans of 85-145-90 m. It is the result of a conscious and rigorous conceptual design process, that took into consideration the special context and boundary conditions, in some cases, quite unusual for a road bridge. The resulting slender, durable, and elegant bridge fits in the context, providing an iconic, yet subtle reference to this important site.
Cody Dock Rolling Bridge: infrastructure and place
Authors: Nilsson Robert , Jacquemot Alfred , Gianni Giulio , Lucas Tim , Randall-Page Thomas , Knight David
Published: April 2024

The Cody Dock Rolling bridge is a new steel bridge over a dock entrance near the River Lea in London. Spanning seven metres between existing dock walls, it allows the passage of vessels into the dock by rolling along a track such that the deck turns upside down and is lifted clear of the navigation envelope. The bridge is carefully counterweighted so that the centre of gravity is approximately level, allowing the 13.2-ton bridge to roll using only a hand cranked winch. Despite the simplicity of this movement, the design process and fabrication revealed complex and unique engineering challenges arising from combining an adaptive design of a moving bridge with high environmental aspirations and a limited budget.
A New Method for Calculating the Shear Stiffness of RC Beams with Web Diagonal Cracks
Authors: Dou Wei , Wang Shengbin , Jin Yongxue , Xu Dong
Published: April 2024

Investigation shows that long span concrete box girder bridges often suffer from cracking and deflection diseases simultaneously. A considerable number of the cracks are diagonal web cracks, which reflects the reduction of the shear stiffness of the structure. However, the current specifications only consider the adverse effects caused by flexural cracks and ignore the shear deflection. In addition, some scholars have found that the horizontal reinforcement of the web also limits the development of diagonal cracks. This paper carried out shear tests on I-shaped beams with different forms of reinforcement in the web. Then, a new calculation method is proposed to calculate the shear stiffness after diagonal cracking, which takes into account the influence of the vertical and horizontal reinforcement at the same time.
System reliability accounting for corrosion-induced degradation over time
Authors: Celati Simone , Natali Agnese , Salvatore Walter , Thöns Sebastian
Published: April 2024

The remaining lifetime of concrete structures subjected to chloride-induced corrosion has been studied in many papers. However, few studies so far consider explicitly experiences from case studies, jointly several corrosion mechanisms and a system perspective. This paper introduces a methodology to evaluate the time-dependent system reliability for concrete bridges subjected to reinforcement corrosion. Here, both chloride and carbonation induced corrosion is jointly considered building upon the thermodynamic conditions for corrosion. The corrosion propagation is modelled with a structural system reliability analysis where different structural system models for repair and replacement consequences are developed. The developed approaches and models are applied to a bridge case study and the service life extension is quantified.
Assessment of Strength and Stiffness Properties of Wood in Existing Structures
Authors: Ozola Lilita , Petersons Martins
Published: April 2024

In this study specimens cut from intermediate timber floor beams that have been in service for more than 120 years were tested. The objective of this paper is to determine the strength characteristics and stiffness modulus of old wood and examine relationships between different properties. Experimental tests for determining the mechanical properties in bending have been carried out in short-term static loading. Also shear strength and compression strength perpendicular to the fiber direction was determined by tests. It is concluded that the modulus of elasticity of wood during long-term service under load decreases faster than the strength properties. When evaluating the relationship between wood strength and stiffness properties, a weak correlation was found between bending strength and modulus of elasticity. As well as other properties (density, moisture content etc.) didn’t show any remarkable correlation significance.
Super-Low-Carbon Footbridge Design
Authors: Curry Ben , Fleming Callum , Addy Ben , Groskin Ezra
Published: April 2024

Through the lens of embodied carbon, this paper compares two recent projects by a single team, for the same client, with similar physical constraints. One has been built, the second is in detailed design stage, and the cumulative lessons for future projects are considered.
Humber Bridge side span rocker bearings replacement
Authors: Collins John , Campbell Peter , Barnes James , Bulmer Mark
Published: April 2024

Opened in 1981, the Humber Bridge (UK) is a suspension bridge carrying a dual carriageway and footpaths. It has a main span of 1410 m, and side spans of 280 m and 530 m. Ensuring that strategic bridge crossings remain safe for operation following unforeseen events is essential. Works to the side span bearings supporting the steel deck box at the concrete towers and anchorages provide a case study of such works. In February 2020, new cracks were identified around rocker bearing welds. Lane closures were implemented and repairs of welded steel plates around the cracks were installed. Subsequent investigations included structural health monitoring, inspections and non- destructive testing. While rocking of the A-frames was observed, stick-slip rotation of the pinned connections was present with flexure in the A-frames induced. These findings justified and helped inform parameters for the temporary replacement of the tower rockers in 2021 and 2022.
Strengthening of the A52 Clifton Stage 2 bridge in Nottingham
Authors: Stroscio Riccardo , Malik Akram , Turlier Frédéric , Dangerfield Malcolm
Published: April 2024

The A52 Clifton bridge is a 6-span post-tensioned concrete bridge, which carries the A52 trunk road in the City of Nottingham (UK). The bridge was built in the early 1970’s and comprises two distinct bridges: the South Approach Viaduct and the Main Bridge over the River Trent. In February 2020, severe corrosion was identified within the external strands inside the South Viaduct. Lane restrictions were implemented while further investigations confirmed additional corrosion in the prestressing strands for both superstructures. The assessments revealed shortfalls in strength and led to the design of a deck strengthening solution using additional prestressing tendons. This paper describes the strengthening solution for both superstructures including the construction sequences and discusses the destressing works of a selected number of external redundant strands within the Main Bridge allowing the new strengthening tendons to be fully jacked to their final specified forces.
Tests of stainless steel circular tubular stub columns with seawater sea-sand concrete infill
Authors: Cai Yancheng , Kwan Albert K. H.
Published: April 2024

A series of cold-formed austenitic stainless steel {CFASS} circular tubular stub columns infilled with seawater sea-sand concrete {SWSSC} were designed, fabricated and tested. The CFASS circular tubes had 3 different cross-sections with its nominal outer diameter of 60.5, 114.3 and 165.2 mm. The concrete mixes were of strength levels 35 and 70 MPa. Axial compression tests were carried out to study their structural behaviour in terms of load-strain curve, strength, ductility and failure mode. The test results revealed that the use of SWSSC in place of conventional concrete in CFASS tubes has little effect on the structural behaviour. The test results were also compared with predictions by existing design equations in the codes. It was found that the existing design equations are either un-conservative or overly conservative. A new and more accurate design equation for axially loaded concrete-filled stainless steel circular tubular stub columns was proposed.
Selection and design of wind and earthquake double-excitation vibration mitigation system using fluid viscous dampers for steel residential towers
Authors: Du Bingjie , Zhao Xin , Wang Yang , Huang Yi
Published: April 2024

Fluid viscous dampers can be utilized to control structural vibration as well as to meet the requirements of structural stiffness and strength under both wind and seismic excitations. As they can operate with a wide range of excitation frequencies, a double-excitation vibration mitigation system is introduced. Moreover, various deformation amplification devices, double dampers configurations, and fluid viscous damper parameters are comprehensively analyzed for the system selection for wind and seismic excitations. Using the sensitivity analysis method, structural optimization with the proposed system is demonstrated in the case study of a tall steel residential building.
FLO:RE – A new floor system made of reused reinforced concrete and steel elements
Authors: Bertola Numa , Küpfer Célia , Bastien-Masse Maléna , Fivet Corentin
Published: April 2024

Carefully extracting reinforced concrete (RC) elements from soon-to-be demolished structures and reusing them as load-bearing components is an emerging circular low-carbon alternative to building new structures. As floor construction typically accounts for the most upfront carbon footprint of buildings, this paper presents the design, structural verifications and construction process of FLO:RE, a new floor system built with reused saw-cut RC slab elements and steel beams. To value all pre- existing properties, the new system reuses the RC elements in bending, taking advantage of the existing steel reinforcement. The life-cycle assessment (LCA) shows that the upfront carbon footprint of the reused system can be as low as 5 kgCO2,eq/m2, reducing by up to 94 % compared to conventional RC flat slabs. The construction and monitoring of a 30-m2 mock-up demonstrate the new-system construction ease and structural performance. This study proves the technical feasibility of reusing old RC slab elements in new floor systems.
Modular construction and component-based bridge design to minimise waste
Authors: Armitage John , Robinson Philip , Chunge Musa
Published: April 2024

Modular construction and component-based design present significant opportunities to improve the efficiency of the design and construction process for bridges. Development of a lean system for the construction of bridges in recent years has driven significant increases in construction productivity. The associated programme savings have led to environmental benefits including carbon savings from reduced timescales on site and reductions in associated preliminaries. The system also facilitates reduction in numbers of people required on site.

A modular system was developed for construction of bridges for HS2 at Birmingham Interchange. Here the system resulted in savings of 8 weeks in the construction of bridge abutments, as well as an 8% reduction in embodied carbon for the abutments and wingwalls, and a reduction of construction labour for the abutments of 84%. Subsequent schemes have seen further development of the system and repeating and increasing benefits.
Neural Network Dynamic Metamodels for a Highly Detailed Cable-Stayed Bridge Finite Element Model
Authors: Tiprak Koravith , Takeya Kouichi , Sasaki Eiichi
Published: April 2024

Despite Finite Element Analysis (FEA) having a strong theoretical foundation with high accuracy, its significant limitation in computational time is highlighted when a large number of FEAs is required. This study thus desires to address the issue by investigating the capabilities of Neural Networks (NNs) in being surrogate models of highly detailed FE models. The generalized processes of the NN model development and the exemplar architectures of the NN models for predicting the frequencies and mode shapes are first proposed before being applied to the task of high dimensional Finite Element Model Updating (FEMU) of a complex cable-stayed bridge. Then, the aspects of the computational time, accuracy, and challenges of the NNs in future works are discussed. Results from the FEMU that utilizes the multi-restart Genetic Algorithm (GA) emphasize the efficiency of the NNs in leading the GA toward an updated FE model that better replicates the actual dynamic responses.
Teaching Reuse of Existing Structures at the University of Sheffield
Authors: Harpin Richard , Carr Jon
Published: April 2024

In response to the Climate Emergency, and to reflect the fact that many practising Structural Engineers work on existing buildings and other structures, staff from The University of Sheffield set up a new ‘Reuse of existing structures’ module in September 2022.

The paper describes the rationale behind the module, the module content, the approach to learning, teaching and assessment., as well as reflecting on the overall success of the module, taking into account the quality of the working submitted and student feedback.
EVALUASI WEBSITE OPEN DATA KOTA SUKABUMI BERDASARKAN STANDAR ISO/IEC 9126
Authors: Nurazizah Rika Agisha Siti , Yustiana Indra , Hermanto Hermanto
Published: April 2024

Open data Kota Sukabumi adalah sebuah inisiatif untuk memberikan akses terbuka kepada data publik yang dimiliki oleh Pemerintah Kota Sukabumi. Namun, untuk memastikan kualitas dan keamanan data yang tersedia, evaluasi kualitas website Open data Kota Sukabumi perlu dilakukan. Penelitian ini bertujuan untuk mengevaluasi kualitas website Open data Kota Sukabumi menggunakan standar ISO/IEC 9126 dengan menggunakan software WAPT. Penelitian ini dilakukan dengan metode evaluasi kualitatif menggunakan wawancara, observasi, dan kuesioner. Hasil penelitian menunjukkan bahwa website Open data Kota Sukabumi memenuhi kriteria kualitas pada beberapa area seperti fungsionalitas, reliability, efficiency, dan usability. namun masih perlu perbaikan pada area keamanan dan reliability. Pengguna website juga memberikan umpan balik positif terkait kualitas website Open data Kota Sukabumi dengan skor rata-rata 3,5 dari skala 1-5. Penelitian ini memberikan gambaran tentang kualitas website Open data Kota Sukabumi dan saran untuk perbaikan ke depan. Hasil penelitian ini dapat digunakan Pemerintah Kota Sukabumi dalam meningkatkan kualitas dan keamanan website Open data Kota Sukabumi.
SISTEM PAKAR DIAGNOSA GANGGUAN KECEMASAN (ANXIETY DISORDER) MENGGUNAKAN METODE FORWARD CHAINING
Authors: Muhammad Khithoh Sabda , Fitrani Arif Senja , Setiawan Hamzah
Published: April 2024

Gangguan kecemasan merupakan salah satu masalah kesehatan mental yang paling umum, kondisi ini dapat mengakibatkan kekhawatiran yang berdampak buruk pada rutinitas seseorang, menurunkan prestasi akademis, serta mengurangi kualitas hidup dan psikologis. Masyarat sering mengabaikan masalah kesehatan mental karena kurangnya pengetahuan dan keterbatasan fasilitas psikologis. Berdasarkan keterbatasan tersebut sistem pakar daharapkan mampu memecahkan masalah tersebut dengan melakukan konsultasi secara mandiri. Sistem pakar adalah sebuah sistem yang mengadopsi pengetahuan pakar sehingga dapat melakukan seperti yang dilakukan pakar. Dengan dibangunnya sistem pakar ini dapat membantu masyarakat untuk melakukan konsultasi di web secara secara mandiri tanpa harus ke tempat fasilitas psikologis. Sistem pakar ini menggunakan metode forward chaining dan dibuat dengan memanfaatkan bahasa pemrograman PHP dan MySQL sebagai database. Metode forward chaining diawali dengan sekumpulan fakta untuk menemukan ketentuan yang sesuai dengan prediksi yang mengarah kesimpulan. Hasil dari pengujian validitas aplikasi, sistem pakar ini memiliki nilai keakuratan sistem sebesar 100% dari 7 data uji.
EFFICIENCY OF CMMS (COMPUTERIZED MAINTENANCE MANAGEMENT SYSTEM) PROJECT STAGES WITH K-MEANS
Authors: Sukmana Farid , Rozi Fahrur
Published: April 2024

This study scrutinized four CMMS (Computerized Maintenance Management System) development projects using the K-Means clustering method to evaluate stages that require improvement by the GrX team. The projects under consideration were named Tim, Lix, Akb, and Mnk. The results indicated that the Tim project leaned more towards efficient CMMS development stages, while the Lix and Akb projects were predominantly in less efficient clusters at the implementation stages. The Mnk project had stages in less efficient clusters located at stages other than implementation processes. This suggests that each project has its unique challenges in achieving efficiency. However, the overarching conclusion is that the GRX team needs to enhance efficiency in the CMMS software development process. Several stages need to be evaluated, particularly the “data analysis and coordination” and “implementation of asset, work order, preventive and spare part modules” stages. Inefficiency occurs when the designing work time has a value lower than twice the workload. The K-Means algorithm was employed in the clustering process because it was believed that the data to be grouped was well-suited for implementation with this algorithm. The variables involved in this study were time and workload. This research provides valuable insights into the efficiency of CMMS development projects and offers a roadmap for future improvements.
Bilgisayarlı Görüde Öz-Denetimli Öğrenme Yöntemleri Üzerine Bir İnceleme
Authors: Alasu Serdar , Talu Muhammed Fatih
Published: April 2024

Derin öğrenme modelleri son on yılda görüntü sınıflandırma, nesne tespiti, görüntü bölütleme vb. bilgisayarlı görü görevlerinde büyük başarılar elde etmelerine rağmen denetimli öğrenme yaklaşımında olan bu modellerin eğitiminde büyük miktarda etiketli veriye ihtiyaç duyulmaktadır. Bu nedenle, son yıllarda insanlar tarafından manuel olarak etiketlenen veriye ihtiyaç duymadan etiketsiz büyük boyutlu veriden faydalanarak genelleştirilebilir görüntü temsillerini öğrenebilen öz-denetimli öğrenme yöntemlerine ilgi artmıştır. Bu çalışmada, bilgisayarla görü görevlerinde kullanılan öz denetimli öğrenme yöntemleri kapsamlı bir şekilde incelenmiş ve öz denetimli öğrenme yöntemlerinin kategorizasyonu sağlanmıştır. İncelenen öz-denetimli öğrenme yöntemlerinin görüntü sınıflandırma, nesne tespiti ve görüntü bölütleme hedef görevleri için performans karşılaştırmaları sunulmuştur. Son olarak, mevcut yöntemlerdeki sorunlu hususlar tartışılmakta ve gelecek çalışmalar için potansiyel araştırma konuları önerilmektedir.
Distribution of allele and genotype frequencies for the IL5 rs2069812 polymorphism in occupational asthma according to its phenotype
Authors: Babanov S. , Baikova A. , Strizhakov L. , Agarkova A.
Published: April 2024

Molecular genotyping opens up fresh opportunities to search for a more targeted and personalized approach to treating occupational asthma (OA) and to developing an individual strategy for its prevention. Objective. To determine genetic risk markers for OA under the influence of sensitizers, by assessing IL5 rs2069812 polymorphic variants. Subjects and methods. The investigation enrolled 170 patients with different OA phenotypes. The patients were divided into groups according to the OA phenotype: 1) 42 patients with an allergic OA phenotype; 2) 36 patients with a non-allergic OA phenotype; 3) 58 patients with an OA + occupational chronic obstructive pulmonary disease (COPD) phenotype; 4) 34 patients with an OA + metabolic syndrome (MS) phenotype. A control group included 50 healthy individuals. IL5 rs2069812 polymorphisms were determined as part of the study of genetic predisposition to OA. Phenol chloroform extraction was used to isolate DNA from peripheral lymphocyte samples. Genotyping was done by real-time polymerase chain reaction with primers and probes designed using the PrimerQuest program (Integrated DNA Technologies, Inc., USA). Results. The genetic markers for OA were found for the first time after exposure to sensitizers, IL5 rs2069812 polymorphic variants, which can recommend that this genetic marker should be identified during thorough periodic medical examinations in individuals with clinical, functional, and immunological changes upon occupational exposure to sensitizing and irritating substances. Conclusion. The identified marker profiles of the genotypes of OA can optimize an approach to diagnosing, treating, and preventing this disease, and expanding the range of criteria for predicting its course. When a polymorphism in the IL5 gene is detected using a molecular genetic study, the patient needs to be registered for follow-up, repeated respiratory function tests once every six months, thorough periodic medical examinations in a specialized center of occupational pathology, by obligatorily attracting a pulmonologist, an allergist/immunologist, and an occupational pathologist, as well as extensive functional and immunological studies once every two years.