bluuebunny/crossref_metadata_2025 huggingface dataset:
دور إدارة أموال الأيتام في تعزيز الأداء المالي للمؤسسة الاقتصادية: دراسة حالة مؤسسة تنمية أموال الأيتام - الأردن
Authors: النشاش أحمد صبحي أحمد
Published: January 2023

هدفت الدراسة إلى التعرف على مدى استخدام مؤسسة تنمية أموال الأيتام في الأردن لمؤشرات الربحية، ودوران المدينين، والرافعة المالية، والسيولة كأدوات إدارة الأموال في تعزيز الأداء المالي، والكشف عن واقع إدارة الأموال وإبراز واقع الأداء المالي في مؤسسة تنمية أموال الأيتام، والتعرف على الفروق في استجابات أفراد العينة تجاه إدارة أموال الأيتام وتحقيق الأداء المالي، وقد وظف الباحث المنهج الوصفي التحليلي، وكانت أداة الدراسة هي الاستبانة، من خلال توزيعها على عينة عشوائية بسيطة شملت (60) من المجتمع الكلي للعاملين في المؤسسة والبالغ عددهم (224)، وتم استرداد (50)، وتم استخدام برنامج التحليل الاحصائي (spss)، كما استخدم تحليل المحتوى للتقارير المنشورة للمؤسسة من عام 2015 حتى عام 2019، وكانت أهم النتائج ما يلي: تستخدم مؤسسة تنمية أموال الأيتام لمؤشرات الربحية في إدارة الأموال لتعزيز الأداء المالي بتقدير مرتفع بلغ 73.6%، وهذا يدل على العلاقة الإيجابية بين الربحية والأداء المالي، كما أظهرت النتائج استخدام مؤسسة تنمية أموال الأيتام لمؤشرات دوران المدينين في إدارة الأموال لتعزيز الأداء المالي بتقدير مرتفع بلغ  66.2%، وهذا يدل على العلاقة الإيجابية بين  دوران المدينين والأداء المالي، وكشفت النتائج ان استخدام مؤسسة تنمية أموال الأيتام الرافعة المالية في إدارة الأموال لتعزيز الأداء المالي بتقدير مرتفع بلغ 76.6%، وهذا يدل على العلاقة الإيجابية بين الرافعة المالية والأداء المالي، كما تبين النتائج أن استخدام مؤسسة تنمية أموال الأيتام للسيولة في إدارة الأموال لتعزيز الأداء المالي بتقدير مرتفع بلغ 69.2% وهذا يدل على العلاقة الإيجابية بين السيولة والأداء المالي، وتبين أيضاً بعدم وجود فروق ذات دلالة إحصائية عند مستوى دلالة (0.05≥α) في استجابات أفراد العينة اتجاه متغيرات الدراسة (إدارة الأموال، الأداء المالي للمؤسسة الاقتصادية)، وأخيراً تبين مؤشرات إدارة الاموال ومؤشرات الأداء المالي في المؤسسة انها تتمتع بالصحة التنظيمية والفعالية المالية وذلك من خلال استخدام تحليل النسب والتحليل الرأسي والافقي.
الاسطورة والتراث في حضارة العراق القديم:ملحمة كلكامش انموذجاً
Authors: الصراف عبدالرحمن عبدالله
Published: January 2023

يتناول البحث جزء من خزين التراث الانساني الذي عرفته حضارة العراق القديم    ( حضارة وادي الرافدين)، هذه الحضارة انتجت لنا سفرا خالدا كما و نوعا من العلوم و المعرفة الانسانية و منها العلوم و الملاحم و الاساطير  التي خلدت لنا الانسان و الارض و البطولة و الخلود و منها ملحمة كلكامش مدار بحثنا هذا، كانت هذه الملحمة نتاج هذه الحضارة بكل ما عرفته من تقدم و مضي نحو حركة التاريخ الى الامام، ان ملحمة كلكامش هي نتاج التراث الانساني في حضارة وادي الرافدين، حكت لنا قصة البطولة و الحياة الابدية على مدى الزمن ذلك العصر العراقي الانساني.
الضرائب والرسوم العائدة كليا لفائدة البلديات
Authors: الجازي منى مرضي ضاري
Published: January 2023

هدفت الدراسة إلى الكشف عن كيفية تنظيم المشرع الأردني للضرائب والرسوم الجبائية العائدة كليا لفائدة البلديات، ولتحقيق اهداف الدراسة ابتعت الدراسة المنهج الكيفي، وتم جمع البيانات من خلال مراجعة التشريعات والقوانين والتقارير والمواقع الرسمية والأدبيات التي تناولت موضوع الدراسة، وأظهرت النتائج  بلوغ معدل الإيرادات الضريبية والرسوم العائدة كليا لفائدة البلديات إلى الإيرادات المحلية بالأردن خلال الفترة (2016-2020) 61%، ويتم تحصيلها من ضرائب المفروضة على المشتقات النفطية والأبنية والأراضي، وتراخيص المهن والأبنية والإنشاءات، وكذلك الرسوم المفروضة على الفاكهة والخضار والمكاييل، وبيع الحيوانات، والاعلانات، والمقاهي، والملاهي، ودور السينما، ومواقف السيارات وغيرها من الرسوم المفروضة على الجهات التي تقدم خدمات للمواطنين. وأظهرت النتائج  ايظا ان معدل قيمة إيرادات الضرائب العائدة كليا لفائدة البلديات خلال الأعوام (2016-2020) 8.57 مليون دينار أردني. من أهم المعوقات التي تحول دون زيادة إيرادات الرسوم والضرائب العائدة بالفائدة الكلية للبلديات هي ضعف النظام الضريبي، وارتفاع معدلات البطالة حيث وصلت أعلى نسبة للبطالة 24.7% خلال عام 2020، وارتفاع معدلات الضرائب حيث بلغ العبء الضريبي على الفرد نسبة24.2%، خلال عام 2020، وقضايا الفساد المالي حيث بلغ عدد ملفات قضايا الفساد المالي في النظام الضريبي إلى 276 ملفا. وقدمت الدراسة مجموعة من التوصيات من أهمها اتخاذ إجراءات فعالة في اصلاح النظام الضريبي بحيث يراعي يتضمن الأساليب والحيل المستحدثة ويسد الثغرات التي يستغلها المكلفين للحد من التهرب الضريبي، انشاء مشروعات لتشغيل الشباب والحد من ارتفاع نسبة البطالة، مراجعة النظام الضريبية بالنسبة لحجم الضرائب بحيث تكون معقولة ومناسبة للأوضاع الاقتصادية التي يعيشها المواطن الأردني، زيادة إجراءات الرقابة للحد من ممارسات الفساد المالي.
القدرة التنبؤية للقيم الاجتماعية وعلاقتها بالتوافق النفسي لدى عينة من طالبات كلية إدارة الأعمال بجامعة حفر الباطن
Authors: الشمراني سمر بنت مطر
Published: January 2023

هدفت الدراسة إلى التعرف على مدى القدرة التنبؤية للقيم الاجتماعية وعلاقتها بالتوافق النفسي لدى عينة من طالبات كلية إدارة الأعمال بجامعة حفر الباطن. واستخدمت الباحثة المنهج الوصفي الارتباطي. وطبق على عينة من طالبات كلية إدارة الأعمال بجامعة حفر الباطن قدرت بـ (211) طالبة من طالبات كلية إدارة الأعمال بجامعة حفر الباطن في منطقة حفر الباطن بالمملكة العربية السعودية. وأظهرت النتائج وجود علاقة ارتباطية طردية بين القيم الاجتماعية، والتوافق النفسي لدى العينة المبحوثة، ويمكن التنبؤ بالتوافق النفسي من خلال درجاتهن في القيم الاجتماعية. ونوقشت نتائج الدراسة في ضوء إطارها النظري والدراسات السابقة وتم تقديم بعض التوصيات.
الأوراق العلمية بين مطرقة الاقتباس وسندان التحكيم: دراسة وصفية تحليلية
Authors: آدم أبكر عبدالبنات
Published: January 2023

تناولت هذه الدراسة موضوع الأوراق العلمية بين مطرقة التحكيم وسندان الاقتباس، حيث تشكل البحوث العلمية إحدى الأهداف الإستراتيجية ذات الطبيعة الإنسانية، التي تحاول معرفة حاجات الإنسان الأساسية التطبيقية منها والنظرية لمعرفة ثقافة الآخرين، والوصول إلى نتائج علمية تسهم في حل قضايا المجتمع، فضلاً عن معرفة أهمية اقتباس المعلومات من مصادرها الأساسية، والكشف عن الغاية من التحكيم الموضوعي، والمعرفة بطبيعة فلسفة البحث العلمي للوصول إلى الحقائق العلمية الثابتة؛ والمحتملة لأجل خدمة المجتمع. وهذا يتطلب معرفة كيف يمكن تطبيق قواعد البحث العلمي في حياتنا اليومية، أيضاً هدفت الدراسة إلى الإلمام بالملاحظات التفسيرية العلمية منها والتحليلية والتطبيقية والمقارنة لشرح الخطوات الموضوعية في الاقتباس والتحكيم. استخدم الباحث المنهج الوصفي والتحليلي، والمقارن للكشف عن كيفية نشر الأوراق العلمية.
Characterization of the Mobile User Profile Based on Sentiments and Network Usage Attributes
Authors: Morais Leonardo P. de , Immich Roger , Silva Nádia Félix , Rosa Thierson Couto , Borges Vinicius da Cunha Martins
Published: January 2023

Providing resources to meet user needs in futuristic mobile networks is still challenging since the network resources like spectrum and base stations do not increase in the same proportion as the accelerated growth of network traffic. Because of this, human/user behavior attributes can assist resource management in dealing with these challenges, which pick up aspects of how the user impacts the usage of mobile networks, such as network usage, the content of interest, urban mobility routines, social networks, and sentiment. A user profile is a combination of user/human behavior attributes. Such profiles are expected to be a knowledge for softwarization enablers to improve the management of future wireless networks fully. Nevertheless, the correlation between human sentiment and wireless and mobile network usage has not been deeply investigated in the literature about the mobile user profile. This work aims to define the user profile using a transfer learning approach for the sentiment classification of WhatsApp messages. A real-life experiment was conducted to collect users' attributes, namely the WhatsApp messages and network usage. A new data analysis methodology is proposed that consists of a frequent item-set pattern mining (FP-Growth) based on Association Rules, the Chi-squared statistical test, and descriptive statistics. This methodology assesses the correlation between sentiment and network usage in a profound way. Results show that the users participating in the experiment form three groups. The first group, with 55.6% of the users, contains users who present a strong relation between negative sentiment and low network usage and also a strong relation between positive sentiment and high network usage. The second group contains 25.9% of the users and is composed of userswho present a strong relation between positive sentiment and high network usage. The third group contains 18.5% of the users for whom the correlation between sentiment and network usage is still statistical significant, but the strength of this relation is much more weak then in the other two groups. Thus, 81.5% of the users (the first two groups) present a strong relation between user sentiment captured from WhatsApp messages and the network traffic generated by them.
Paul Delaroche — Das Phänomen globaler Berühmtheit im 19. Jahrhundert
Authors: Hackmann Lisa
Published: January 2023

Der Historienmaler Paul Delaroche (1797–1856) inszenierte in seinen Bildern wirkungsvoll die schicksalhaften Momente gekrönter Häupter der englischen und französischen Geschichte. Damit wurde er nicht nur in Europa, sondern auch in Nordamerika zu einem gefeierten Künstler. Lisa Hackmann beleuchtet erstmals die außergewöhnliche Berühmtheit dieses Malers. Ihr Fokus liegt auf der wachsenden Rolle der Kunstöffentlichkeit, der Kunstkritik und dem rasant expandierenden Kunstmarkt. Damit eröffnet sie einen neuen Blick auf sich verändernde gesellschaftliche und mediale Rahmenbedingungen für Künstlerkarrieren in der ersten Hälfte des 19. Jahrhunderts.
Alessandro Magnasco (1667-1749)
Authors: Mende Charlotte
Published: January 2023

Der Band entschlüsselt erstmals die „Religionsbilder“ des italienischen Malers Alessandro Magnasco (1667–1749) vom Übergang des Spätbarock zum Rokoko als bildhafte Argumente des Religionsdiskurses. Die Gemälde widmeten sich der Darstellung religiöser Praktiken so unterschiedlicher Glaubensgemeinschaften wie der Juden, Christen – darunter auch Quäker – aber auch der Paganen und dem volkstümlichen Aberglauben.

Unter den Aspekten von Ikonographie, Pendantbildung und zeitgenössischer Rezeption untersucht Charlotte Mende, wieso bestimmte religiöse Riten Bildwürdigkeit erlangten. Welche Inspirationsquellen bedingten Magnascos eigenwillige Bilderfindungen und wie gingen die damaligen Sammler damit um?
Vzťah koncernu Baťa k režimu Slovenskej republiky 1939–1945 na stránkach časopisu Budovateľ
Authors: Ľudovít Hallon
Published: January 2023

The Slovak branch of the international Bata Corporation gradually came into existence in the 1930s, with the process culminating during the existence of the Slovak Republic between 1939 and 1945. In January 1939, the branch also started a magazine, named Budovateľ and targeted at the Slovak factories of the corporation. The magazine, whose content would be created by its editors, provided information about life in the factories, but also presented the official attitude of the Slovak branch’s top management towards the government and the political system of Slovakia at that time. The study maps and evaluates the attitudes (or certain aspects thereof) expressed in Budovateľ in the period 1939 to 1941, when the government of the independent Slovak Republic was on the rise and could boast some economic and social achievements and when the idea of national unity resonated in the broader populace. The study analyses these attitudes up to June 1941, specifically until the attack on the Soviet Union by Nazi Germany. In the months and years that followed, the views of the management and rank-and-file employees at Bata’s plants in Slovakia gradually began to change under the influence of domestic and international developments in the context of the world war.
Tomáš Baťa a národohospodářské otázky nového Československa 1918–1923 ve vzájemné korespondenci s Františkem X. Hodáčem
Authors: Jan Herman , Milan Balaban
Published: January 2023

A leading Czechoslovak entrepreneur, Tomáš Baťa has been the subject of constant attention and his business activities have been examined in many ways. Less attention, however, has been paid to Baťa’s thoughts and opinions. This is undoubtedly because he rarely spoke out openly on questions of national economy in his public appearances. Based on seven letters exchanged with his friend František X. Hodáč from 1918 to 1923, this article reconstructs Baťa’s views on the political, social and economic situation of the newly created Czechoslovak state. At this time, the Bata Corporation had to cope with post-war economic disruptions and uncertainty in international relations. In the daily struggle for the economic survival of the corporation, he also ventured into the sphere of economic theory, taking a stance on issues such as devaluation, profit and loss, prices and wages, and the foreign interests of the state. Baťa would meet the leading figures of the state and, in discussions with finance ministers Alois Rašín and Karel Engliš, his views matured and exerted a considerable influence on people involved in economic theory and policymaking in Czechoslovakia.
Pokusy o demokratizaci volebního systému ve druhé polovině šedesátých let a volby v roce 1971
Authors: Jan Rychlík
Published: January 2023

The political liberalisation of the 1960s had its echo also in reflections about the need to democratise the Czechoslovak electoral system. Elections in communist Czechoslovakia were a farce: they were held in single-member districts, in which only one candidate run, leaving the voter with no choice. Act No 113/1967 of 30 November 1967 on elections to the National Assembly, and the accompanying Act No 114/1967 on elections to national committees, introduced multi-member districts in which the number of candidates was higher than the number of seats. Thus, for the first time since the 1948 elections, voters were given the chance to choose from a multitude of canditates, not just one. The first elections to be held this way were planned for the spring of 1968, but were – also in the context of the preparation of the constitutional act on the federal system – postponed first to autumn 1968 and then to the following year. The Soviet occupation of Czechoslovakia, which began on 21 August 1968, and the onset of what is called normalisation meant that the electoral reform was not realized at all. In the autumn of 1969, elections were again postponed until 1971. For these elections, a new electoral law was adopted, bringing back the old practice of single-member districts with but one candidate running. The elections held in 1976, 1981 and 1986 followed that undemocratic procedure.
Evropské paralely pro scestí a selhání federalistického myšlení v prostoru bývalého Československa
Authors: Vladimír Goněc
Published: January 2023

This paper is based on Constantin Frantz’s concept of a true “federation for citizens”. Frantz’s concept has been misunderstood and neglected by a large part of the persons involved in constitutional thinking in the mid 19th century Bohemia and Upper Hungary, that is, the territories of today’s Czech and Slovak Republics. The result of that neglect and misunderstanding was delusion. The Czech Faculty of Law at Charles University in Prague became a stronghold of dogmatic centralist thinking; it found itself in conflict with other university faculties in interwar Czechoslovakia. With the take over of the Communist Party in February 1948, critical federalist thinking vanished, as a result of government domestic policy. After August 1968, critical federalist thinking as a concept of federation ceased to exist, since the concept ‘federation’ was bereft of its true sense. This resulted in the painful lack of understanding of the inherent problems of federalism and decentralisation in the early 1990s.
The Legal Status of Gibraltar after Brexit in Light of the Provisions of the Protocol on Gibraltar
Authors: Gapsa Michał
Published: January 2023

Gibraltar remains subject of an ongoing British-Spanish dispute over sovereignty. Nevertheless, membership of the United Kingdom in the EU stabilized the cross-border situation. Clearly, Brexit has threatened the established status quo. The legal status of Gibraltar is regulated in a special Protocol attached to the Withdrawal Agreement. It provides for deepened British-Spanish collaboration in the sectors of fishing, environmental protection, police and customs cooperation and the rights of citizens living in border areas (especially important for the Spanish region of Mancomunidad de Municipios del Campo de Gibraltar). However, compared to other Protocols, the arrangements for Gibraltar are extremely narrow. It was undecided to subject the peninsula in a greater extent to EU law than the rest of the United Kingdom. It is likely that these shortcomings will be regulated by a future EU-British Agreement governing the status of Gibraltar.
SUSTAINABLE MOBILITY AND THE ECOLOGICAL FOOTPRINT OF THE TEHRAN METROPOLIS UNDER INTERNATIONAL SANCTIONS
Authors:   University of Geneva, Switzerland, Hashemi Behramani Alireza
Published: January 2023

This paper is aimed to analyse the existing relationships and controlling functions between ecological footprint and international sanction in case of Teheran city. The analysis begins questioning whether the sustainability of health on our common planet is rightly treated with oblivion to the pernicious consequences from the economic blockade of one country by the global community. The analytic method used is based on developing a conceptual and theoretical framework of reference to review the literature, interviews on the main variables of the research: urban policy, transport system, international sanctions and multi scale governance. It is concluded that while that the existence of more holistic facilitating the development of the rail transport system, the governance and stakeholders put a lot of obstacles and play at a different scale. The analysis suggests that a holistic approach is required to build urban mobility based on decreasing of ecological footprint by addressing a fuller range of degradation public health, urban politicisation, to process the policy of the multi-scale governance of city, to create the governance that implies geographical proximity, organisational proximity and institutional proximity of stakeholders.
RE-THINKING THE URBAN: THE THEORY OF AFFECT AND URBAN INTERIORITY AS A WAY OF THINKING NEW POSSIBILITIES
Authors:   Faculty of Architecture and Design, Pamukkale University, Denizli, Turkey, K. SOZGEN Ecehan
Published: January 2023

Body interacts with the space through undefinable, unpredictable actions and behaviors. Predictability disappears when the performativity of the body is taken into account. By dissolving and decoding the boundaries of space, the body challenges spatial dichotomy and prepares the new possibilities of thinking and understanding. Space becomes productive with new lines of escape and possibilities. Design as a temporary moment of intensity in the rhythm of daily life, on the other hand, recalls the affect that has been postponed in the academic field in architecture. At this point, affect theory together with the concept of interiority create a new discussion on space by questioning the existing theories. Affect plays a role in the spatial production of urban interiority; at the same time, urban interiority nourishes the affect. Exploring the neglected dimensions of our daily lives and the relational aspects of experience that produce and shape it, thinking about body, subjectivity and desire with non-representational theory in the focus of space: this is where the study turns towards the theory of affect. It produces a new understanding of relationality and space built with interactions between human/non-human, body and city, reflecting on different subjectivities and a different perspective to understand the city. It lays the groundwork for the appropriation of cities through their affective capacities and layers. In any case, it is not enough to think on urban space and architectural practice within disciplinary boundaries; they are in a constant state of formation and construction under the influence of different parameters. This study aims to rethink the concept of urban interiority through affect theory and aims to multiply questions about different becoming and possibilities rather than seeking answers.
Application of Elastic Reverse Time Migration to Ultrasonic Echo Data in Civil Engineering
Authors:   BAM Federal Institute for Materials Research and Testing, Grohmann Maria ,   BAM Federal Institute for Materials Research and Testing, Niederleithinger Ernst ,   TU Bergakademie Freiberg, Buske Stefan
Published: January 2023

The ultrasonic echo technique is widely used in non-destructive testing for investigation and damage analysis of concrete constructions. To improve the ultrasonic imaging of complicated structures in concrete, we transferred a seismic migration technique, the Reverse Time Migration (RTM), to non-destructive testing. In a preliminary study, we tested a 2D acoustic RTM algorithm on measured ultrasonic echo data acquired at a concrete foundation slab. Compared to the conventional used synthetic aperture focusing technique (SAFT) algorithms for ultrasonic data reconstruction, our acoustic RTM results showed a significant improvement in imaging the interior structure of the concrete slab.
In contrast to SAFT, RTM is a wavefield-continuation method in time and uses the full wave equation. RTM is, thus, able to include multiple reflections and to handle multi-pathing as well as many other complex situations. As a drawback RTM requires extensive computing power and memory capacity.
An RTM algorithm that uses the full elastic wave equation instead of the full acoustic one (as applied in our preliminary work) has the potential to optimize the imaging results even further. This is due to the fact, that our ultrasonic data are generated by exciting elastic waves. In a first step, we tested two 2D elastic RTM algorithms on synthetic ultrasonic echo data generated with a concrete model. Our synthetic elastic RTM results showed an enhancement in imaging the features inside the test model compared to acoustic RTM and SAFT. In a second step, we acquired ultrasonic measurement data at a concrete specimen consisting of three steps and four air-filled tendon ducts. Processing the real ultrasonic data with our elastic RTM codes was successful and improved the reconstruction of the geometries of the steps and tendon ducts. With our study we have shown that elastic RTM is a step forward for ultrasonic testing in civil engineering.
Development of a portable measuring system using ultrasound guided and surface waves to characterize concrete structures
Authors:   Electricité de France (EDF) R&D, Henault Jean-Marie ,   Electricité de France (EDF) R&D, Moulouel Rafik ,   Electricité de France (EDF) R&D, Raveendran Thilakson ,   Electricité de France (EDF), Denos Yves ,   EDF - CEIDRE, Boule Alexandre ,   EDF - CEIDRE, Bisarah Philippe ,   LMDC INSA-UPS, Balayssac Jean-Paul ,   Aix-Marseille University (AMU), Chaix Jean François ,   Aix-Marseille University (AMU), Garnier Vincent ,   University of Toulouse, Mailhe Jean ,   Commissariat à l’Energie Atomique (CEA), Recoquillay Arnaud
Published: January 2023

A portable system was developed to be used in lab and on field. The system is composed of one emitter and 60 receivers. All of them are Dry Point Contact sensors, P-wave, S1803 from ACSYS, with a nominal frequency of 100kHz and a wide frequency range from 15kHz to 175kHz. The 60 receivers are equally spaced of 5mm which enables to make measurements over 30cm. The acquisition is made with a two-channels A1560 ACSYS device. We developed an electronic part to multiplex the acquisition of all the receiver signals. A Raspberry-Pi device is used to control four 16-channels analogic multiplexers. We designed and manufactured with a 3D-printer a holder for the DPC sensors and the electronic part. The A1560 device and the Raspberry-pi are controlled with a Python program on a digital tablet. For one acquisition, which lasts a few seconds, 60 a-scans are registered. Several acquisitions are repeated by moving the system of a few centimeters. The results are averaged to lower the incoherent part of the signals due to multi-scattering effects on concrete aggregates. The result is processed with a p-w Transform to get the dispersion diagram and to assess the dispersion curve.
In the case of surface waves, when the structure thickness is larger than the smallest wavelength, the dispersion curve can be inversed with a tool like Dinver from Geopsy. The final result is the ultrasound speed profile with depth.
In the case of Lamb waves, the dispersion curve is compared to A0 and S0 modes calculated with a tool like Disperse form Imperial College or CIVA frome CEA.
This efficient tool is used to study different concrete structures:
- thick structure with concrete cover affected by carbonation or leaching,
- thin structure like 6cm-thickness and 60cm-diameter concrete/steel/concrete pipes used in the nuclear industry.
Digital Building Diagnostics
Authors:   FH Erfurt- University of Applied Sciences (FHE), Arndt Ralf ,   FH Erfurt- University of Applied Sciences (FHE), Voigt Chris ,   Marx Krontal Partner, Fritsch Christina ,   Bau-Consult Hermsdorf Gesellschaft beratender Ingenieure mbH, Eric Ewert ,   Bau-Consult Hermsdorf Gesellschaft beratender Ingenieure mbH, Burkhardt Joerg
Published: January 2023

Abstract Englisch

Many manual steps are usually required in the acquisition, evaluation and presentation of building diagnostic results. In the case of questions with practical relevance several non-destructive testing methods and conventional building diagnostic are customary used. The data obtained are heterogeneous and available in a wide variety of types and formats, including as manual records in measurement protocols or digitally stored on various measuring devices as well.

As part of the research project "Digital Building Diagnostics", the project partners (University of Applied Sciences Erfurt, Marx Krontal Partner and Bau-Consult Hermsdorf) are developing methods and procedures to digitize the sub-processes of non-destructive building diagnostics procedures on concrete structures like GPR, ultrasound echo among others and, if possible, to automate them. Essential information is to be digitally recorded with a recording tool and stored in a database already on the building. In the office, further measurement data from the non-destructive test procedures are transferred to the database with the help of a converter. Imaging processes are evaluated by experienced engineers and the results are also stored in the database. With the help of an evaluation tool, data from the database is aggregated in a semi-automated manner and evaluated with subject-specific algorithms. The individual results and the evaluations are located and visualized in a three-dimensional building model. Through the representation in three-dimensional space, connections can be better recognized, and more precise conclusions can be drawn.
Nondestructive evaluation of select bridges in Iowa, USA using high-speed and ground-coupled robotic NDE platforms
Authors:   Infratek Solutions Inc., Zain Syed ,   Infratek Solutions Inc., Rezvani Amir ,   Drexel University, Bartoli Ivan ,   Carl Zeiss X-ray Microscopy, Johnson Bruce ,   Iowa Department of Transportation, Stanisz Joseph ,   Iowa Department of Transportation, Neubauer Scott ,   Iowa Department of Transportation, Todsen Michael
Published: January 2023

This paper intends to provide a detailed assessment of the condition of two select bridge decks in the state of Iowa, USA. The field-data collection was obtained by a novel data collection system called “Infratek insight” which consists of the High Definition (HD) and High Speed (HS) platforms. The data collection took place in two phases. Phase one (HS) used air coupled NDE sensors at traffic speed while phase two (HD) utilized ground coupled NDE sensors using robotic deployment, autonomous navigation and driving systems to eliminate location variability. The data acquisition during both phases was subject to real-time data quality control by a custom data acquisition software that was developed by Infratek. Manual chain dragging was also performed at select areas to inspect the bridge deck condition and to validate data obtained by the insight system.
A suite of NDE technologies were utilized on the High-Speed (HS) and High Definition (HD) platforms including Impact Echo (IE), Ultrasonic Surface Waves (USW), Electrical Resistivity (ER), Ground-Coupled GPR, Air-Coupled GPR, Surface Laser Profilers, 360-Degree Visual Imaging, Infrared thermography (IR), High-Definition Line Scan Imaging and Automated Crack Mapping with Artificial Intelligence Engines, LiDAR and Automated High-Speed Sounding (Chain Drag). ER and GPR are used to assess the corrosion potential throughout the bridge deck. GPR is also used to determine cover depth. IE, Chain Drag and IR are the primary delamination evaluation tools, and USW enables evaluation of concrete quality and degradation. Results indicated a high degree of correlation between the HD and HS platforms and also between individual sensors. The results and maps produced by the HS and HD platforms were utilized in quantifying repairs and providing the asset owner with data-driven recommendations on future rehabilitation actions based on best practices and owner specific criteria.
FEM-based simulation tools for ultrasonic concrete inspection
Authors:   University Paris-Saclay, Dorval Vincent ,   Commissariat à l’Energie Atomique (CEA), Imperiale Alexandre ,   University Paris-Saclay, Darmon Michel ,   Commissariat à l’Energie Atomique (CEA), Demaldent Edouard ,   Electricité de France (EDF) R&D, Hénault Jean-Marie
Published: January 2023

The simulation of nondestructive evaluation is a useful tool in the design of inspection procedure or the interpretation of results. In the case of the ultrasonic inspection of concrete, modeling the complex interaction of ultrasonic waves with the heterogeneous material is challenging.

A finite element code for the simulation of ultrasonic inspections is developed in the CIVA software platform. It is the kernel of a new simulation module dedicated to concrete in a custom version of CIVA. This module relies on automated meshing managed through a user-friendly interface and offers comparatively fast numerical computations. Its aims at modeling practical concrete inspection configurations, involving for example distributions of aggregates, voids and metallic objects. In this communication, we present these modelling efforts and focus on configurations of interests and evaluation of the modelling performances performed in a recent collaboration between CEA and EDF.
Validating a physics-based automatic classification scheme for Impact Echo signals on data from a concrete slab with known defects
Authors:   Pennsylvania State University (PennState), Sengupta Agnimitra ,   Federal Highway Administration (FHWA), Azari Hoda ,   Pennsylvania State University (PennState), Guler Ilgin ,   Pennsylvania State University (PennState), Shokouhi Parisa
Published: January 2023

Impact Echo (IE) is capable of locating subsurface defects in concrete slabs from vibrational response of the slab to mechanical impact. For an intact slab (‘good’ condition), the frequency spectrum of IE is dominated by a peak corresponding to the slab’s ‘thickness resonance frequency’ since much of the impact energy is reflected from the bottom of the deck. The presence of subsurface defects (‘fair’ or ‘poor’ conditions) could manifest in various ways such as multiple distinct peaks at frequencies higher or lower than the thickness resonance. Energy distribution across different frequency bands varies with the type and extent of damage. In previous research, the authors have proposed a frequency partitioning of the spectrum for IE signal classification. First, the thickness resonance frequency band is identified using Gaussian Mixture modeling. Next, IE signals are represented by their energy distribution in three bands – frequencies less than, within and greater than thickness resonance. IE signals are reduced to feature vectors representing the proportion of energy in each band. Following the feature extraction, an unsupervised clustering approach is used to identify the centroids for each signal class – good, fair, poor, which is used to classify any test signal into one of the three classes. The classification is developed by training on unlabeled IE signals from real bridge deck data (Federal Highway Administration’s (FHWA) InfoBridge dataset) without making use of any labeled data. This study aims to validate the proposed methodology developed based on field data on a labeled dataset of eight reinforced concrete specimens constructed at FHWA Advanced Sensing Technology NDE laboratory with known artificial defects: shallow and deep delamination, honeycombing and voids. Findings indicate that the physics-based feature definition and the method developed on real bridge data is robust and can classify IE signals in the labeled data with high accuracy.
Engineering of Existing Structures: The Need and Place for Non-destructive Evaluation (NDE)
Authors:   Ecole polytechnique fédérale de Lausanne (EPFL), BERTOLA Numa ,   Ecole polytechnique fédérale de Lausanne (EPFL), Henriques Guillaume ,   Ecole polytechnique fédérale de Lausanne (EPFL), SCHUMACHER Thomas ,   Ecole polytechnique fédérale de Lausanne (EPFL), Bruehwiler Eugen
Published: January 2023

Structural engineers today are still educated mainly to design new structures. This ignores the fact that structures already exist and need to be maintained. Students are thus often ill-equipped to deal with maintenance and preservation of existing structures. As an example, when a structural analysis model of an existing structure such as a bridge is built to predict its behavior, it is often done without considering the actual behavior or properties - this would require the engineer to have skills and knowledge in the evaluation of existing structures. As a result, these models are often inaccurate, which can lead to unnecessary replacements of structures. This is not only costly but it also significantly impacts the environment. In this paper we argue that new educational programs that specifically address this need should be developed that revolve around the idea of “engineering of existing structures”. Such programs would still include certain traditional structural engineering courses but also discuss structural behavior and materials properties, and how these can be determined by means of non-destructive testing (NDT) and structural health monitoring (SHM), in sum referred to as non-destructive evaluation (NDE). Because these tools are not traditionally included in the structural engineering curriculum, a new set of basic interdisciplinary skills from the domains of mechanical and electrical engineering, as well as computer science (data analysis, signal processing, etc.), need to be acquired by the students. This paper makes a case for the need of this new direction, proposes curriculum adjustments, and gives practical course examples.
Multimodal Nondestructive Evaluation of Industrial Heritage Structures
Authors:   Wiggenhauser Consultant, Wiggenhauser Herbert ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Moryson Ralf Marcel ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Klein Samuel ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Moser Dorothee ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Schäfer Wolfgang ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Pudovikov Sergey ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Herrmann Hans-Georg
Published: January 2023

Industrial heritage structures are a valuable part of a nation's history, preserved and maintained in many countries. Their maintenance and structural assessment is complex and necessary, not only from a safety point of view, but also for their possible reuse, e. g. for cultural events. This study addresses the use of nondestructive evaluation methods for the assessment of these structures under the general perspective of building management. The identification of missing links in the procedures to support management decisions through reliable measurement data is necessary to develop a roadmap for a future integrated system.
Academic education in NDT-CE in the times of pandemia
Authors:   Technical University of Munich (TUM), Grosse Christian U.
Published: January 2023

Suitable for a session on "Training, education and standardization"

Non-destructive testing methods and their basic principles are an integral part of most technical curricula of academic institutions in particular in engineering sciences. The Technical University in Munich (Chair of Non-destructive Testing) is bringing together these basics in a lecture series that is offered to a wide range of disciplines including civil, environmental and mechanical engineering including most NDT techniques including UT, RT, ET, MT, AT, TT, VT, SHM and many more.
NDT is a teaching topic that requires skills from several disciplines including materials science and material testing, measurement techniques and sensors, data processing and computer science, and eventually simulation techniques. According teaching courses can be attractive for students since they offer opportunities to include interesting experiments in the lectures as well as new media.
However, such courses and the practical work are suffering from pandemic situations, where special hygienic requirements are essential. This presentation will present a collection of ideas to tackle this situation with some examples from six months experience during the CoVid19 crisis. The examples include a combination of online teaching courses with exercises, webinars, homework and (limited) practical trainings. The underlying pedagogic concept is following the fundamentals of constructive alignment.
Validation of wireless impact echo prototype for condition assessment of concrete structures
Authors:   University of Ottawa, Noël Martin ,   University of Ottawa, Lacroix Francis ,   FPrimeC Solutions Inc, Moradi Farid ,   University of Ottawa, Layssi Hamed
Published: January 2023

A new wireless impact echo prototype was developed for the condition assessment of reinforced concrete slabs. The new system includes a wireless handheld sensing device which connects by Bluetooth to a tablet equipped with a user-friendly software for managing the testing grid, recording measurements, processing and transforming the data to a frequency domain, and presenting the results in real time. To validate the device, three large-scale concrete slabs of dimensions 2000 mm x 2000 mm x 300 mm were fabricated with artificial defects including voids, delamination, vertical cracks, and geometric discontinuities. The influence of slab boundaries, defect depth and location, overall thickness, steel reinforcement, and an internal conduit on the obtained measurements were investigated. The results were also compared with other commercial non-destructive testing devices including ground penetrating radar (GPR) and ultrasonic pulse velocity (UPE), and the advantages and disadvantages of each method are discussed. Overall, the results suggest that the impact echo technique using the new wireless prototype is able to accurately detect and characterise various defect types provided that the right size of impactor is used. Use of improper impactor sizes can result in alternative vibration modes depending on the slab thickness and defect depth; in that case, multiple readings may be required. The new system greatly improved the ease-of-use of the impact echo technique, although the inspector should be trained to properly interpret the results. Compared with the GPR technique, the impact echo system was not as rapid and unable to detect the location of steel reinforcement; on the other hand, it was better able to detect defects in the presence of steel bars which tended to obscure readings using GPR. UPE measurements were also faster than the impact echo tests and performed well for slab thickness measurements and detection of certain defect types; however, readings were found to be affected by the presence of steel reinforcement and in some cases were inconsistent. Overall, it may be concluded that each technique presents certain strengths and weaknesses that should be considered in the condition assessment strategy. The results obtained from each technique are complementary and may be used to develop a complete understanding of the internal state of the structure.
Inverse modelling of potential measurements on reinforced concrete to assess localized corrosion: Sensitivity with respect to the corrosion state and concrete properties
Authors:   ETH Zürich, Ede Meeke van ,   Cornell University, Earls Christopher J. ,   ETH Zürich, Fichtner Andreas ,   ETH Zürich, Angst Ueli
Published: January 2023

We present a novel, fundamentally sound approach for the determination of corrosion rate and anode location in reinforced concrete. In this contribution, we focus on the sensitivity of this non-destructive method with respect to the state of corrosion and concrete properties.

Corrosion is often the main cause for the premature deterioration of reinforced concrete structures. Especially the type of pitting (or localized) corrosion poses great danger, as it can result in fast local decrease of the steel diameter. Non-destructive testing (NDT) is essential to detect the corrosion at an early stage, without the need to damage the concrete.

The most commonly applied NDT method for reinforced concrete is potential mapping. However, it only predicts the probability of corrosion at a certain location, and does not supply any information about the corrosion rate. Other electrochemical measurements targeting corrosion rate rely on the polarization resistance, based on the mixed-potential theory by Wagner and Traud [1938]. This theory, however, is not applicable to localized corrosion.

A novel inverse modelling approach allows us to detect and quantify corrosion, based on electrical potential measurements at the concrete surface in combination with a small perturbation of the corroding system by an external electrode. Using a 3D finite-element model to describe the electrical potential field resulting from external polarization of the corroding steel, we estimate the location and rate of corrosion through the application of inverse methods.

This study presents the sensitivity of the approach with respect to the degree of corrosion and the concrete properties themselves. We investigated effects of the width of the corroding spot, the cover thickness and the concrete resistivity. First, we analyzed the direct effect of the potentials measured at the surface, using the finite-element model. Secondly, we determine the range of these factors for which the inverse method is able to accurately estimate the corrosion rate and location. This information allows us to understand the limitations of inverse modelling of electrical potential in detecting corrosion in reinforced concrete.
Evaluation of retroreflective corner echo for detection of surface breaking cracks in concrete by ultrasound
Authors:   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Rabe Ute ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Pudovikov Sergey ,   BAM Federal Institute for Materials Research and Testing, Wiggenhauser Herbert ,   Fraunhofer-Institute for Non-Destructive Testing (IZFP), Herrmann Hans-Georg ,   BAM Federal Institute for Materials Research and Testing, Prabhakara Prathik ,   BAM Federal Institute for Materials Research and Testing, Niederleithinger Ernst
Published: January 2023

The retroreflective corner echo is used, for example, in ultrasonic non-destructive testing of metals to find fatigue cracks in tubes or shafts. If the much weaker crack tip signal is additionally detected, the crack length can also be determined. A corner reflection occurs in cases of surface breaking cracks with predominantly perpendicular orientation to the surface. The intensity of the corner reflection depends on the angle of incidence and on the ultrasonic wave mode used. For the reliable detection of vertical surface breaking cracks in metals, transversal waves are commonly used, which propagate at an angle of 37° to 53° to the inspection surface. As shown in this contribution, the wide spread low frequency ultrasonic arrays with dry point contact sources available for ultrasonic testing of concrete also allow to receive corner echoes. These devices generate transversal waves in concrete structures with a large divergence of the sound field. A series of experiments was carried out with such dry point contact arrays on concrete specimens with artificial test defects and controlled induced cracks of different depths. The ultrasonic time-of-flight signals were recorded, exported and reconstructed utilising the SAFT (Synthetic Aperture Focusing Technique) algorithm. The SAFT reconstruction parameters were adjusted to visualize the corner echo indication. As will be shown, with this targeted processing, the reproducible detection of surface breaking cracks in concrete is possible. The retroreflective corner echo can thus be exploited in civil engineering for non-destructive inspection of concrete.
Deep learning-based damage estimation in concrete structures using acoustic emission data
Authors:   Izmir Katip Celebi University, Inderyas Omair ,   Ege University, Tayfur Sena ,   Izmir Katip Celebi University, Arslan Tolga ,   Ege University, Alver Ninel
Published: January 2023

Conventional structural testing methods assess damaged condition of the structures and they generally base on subjective visual inspection. To take necessary precautions before/during a disaster, real-time monitoring of damage progression is very important especially for critical structures such as bridges, viaducts, tunnels, dams and nuclear power plants. Acoustic emission (AE) has been proved to be a successful method for this purpose and it is used to locate even invisible micro-level cracks in the structures. The most important feature that makes this technique advantageous over other non-destructive testing methods is that it continuously monitors damages in structures subjected to load by sensors converting the waves emitted from the damage into electrical signals. By analyzing the parameters of the recorded signals, critical information such as the type, location, origination-time, size and direction of the damage can be obtained.
In this study, it was aimed to estimate damage status of the concrete members exposed to loading by developing a deep learning-based damage detection model. This model was developed by monitoring AE activities of concrete and reinforced concrete specimens with different strength, size, properties and loading conditions. Afterwards, a relationship was established between the properties and load levels of the specimens with features of the AE signals. The developed model was tested on reinforced concrete elements under load. The results show that the model is successful at estimating the damage level.
Acoustic emission signal filtering based on artificial intelligence
Authors:   Ege University, Inderyas Omair ,   Ege University, Tayfur Sena ,   Ege University, Alver Ninel
Published: January 2023

One of the factors affecting the performance of the acoustic emission method used for real-time monitoring of structures is the interference of noise signals with the damage-related AE signals. Since the signals detected from the sensors are analyzed to obtain damage information, noise-related signals cause inaccurate inspection results. Especially, in the conditions where electrical or mechanical friction is prominent, noise causes big data and errors in damage detection
In this study, to solve this problem, it is aimed to develop an AE signal filtering model by artificial intelligence that can filter the noise-related signals. For this purpose, a wide range of AE data were filtered using conventional filtering techniques and noise- and damage-related signals were used to train artificial intelligence. The noise-related signals were successfully separated from the damage-related signals.