Concrete Problems Research Articles

A study on S-asymptotically ω-periodic positive mild solutions for damped elastic systems

The goal of this paper is to consider damped elastic systems with delay and nonlocal conditions in the framework of ordered Banach spaces. Firstly, we investigate the existence of minimal positive S-asymptotically ω-periodic mild solution for structural damped elastic systems with delay and nonlocal conditions on infinite interval. Secondly, based on monotone iterative technique coupled with fixed point theorem, the existence of minimal positive S-asymptotically ω-periodic mild solution is discussed without assuming the existence of upper and lower solutions. Finally, a concrete problem regarding the vibration equation of simply supported beam is given to illustrate the feasibility of our abstract results.

Upper large deviations for power-weighted edge lengths in spatial random networks

AbstractWe study the large-volume asymptotics of the sum of power-weighted edge lengths $\sum_{e \in E}|e|^\alpha$ in Poisson-based spatial random networks. In the regime $\alpha > d$ , we provide a set of sufficient conditions under which the upper-large-deviation asymptotics are characterized by a condensation phenomenon, meaning that the excess is caused by a negligible portion of Poisson points. Moreover, the rate function can be expressed through a concrete optimization problem. This framework encompasses in particular directed, bidirected, and undirected variants of the k-nearest-neighbor graph, as well as suitable $\beta$ -skeletons.

Breves ajustes à contribuição da sociologia histórica ao constitucionalismo latino-americano

Abstract The main objective of the article is to present the historical sociology as a method capable of generating innovative approaches to the field of Latin American constitutional law. Considering the logic of long term (long durée), the article problematizes the need to overcome the constituent dynamics only as a construction of the future to reach a strategy of unveiling continuities. Based on elements of the Brazilian reality, the article presents two cases in which the potential for applying the method of historical sociology to constitutionalism in the region is indicated. First, the permanence of authoritarian legality through the performance of courts after the democratization of the region. Second, the normative constitutional and infra-constitutional formation of the public administration in Brazil. The methodology used is the analytical essay and its foundation, for indicating the concrete historical problems presented, is the opening of the method of historical sociology to the hybridization of disciplines.

Multiagent Systems on Virtual Games: A Systematic Mapping Study

<italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Context</i> : Games are a well-established scenario to test AI and Multi-Agent Systems (MAS) proposals due to their popularity and defiance. However, there is no big picture of the application of this technology to games, the evolution of the kind of problem tackled, or the game scenarios in which agents have been experimented. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Objective</i> : To perform a systematic mapping to characterise the state of the art in the field of MAS applied to virtual games and to identify trends, strengths, and gaps for further research. Method: A Systematic Mapping Study has been conducted to find primary studies in the field. A search was performed on title, abstracts, and keywords, whilst classification, data extraction, and further analysis were performed according to specific criteria focused on MAS papers with experimentation and evidence in a game scenario. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Results</i> : 78 studies published between 1998 and 2021 were found. Studies have been classified according to the MAS problem faced and the agent reasoning strategy. We detect that Machine Learning is the most common AI technique for MAS in games, considering both reinforcement learning and evolutionary techniques. MAS are used in a variety of gaming genres, especially in Real-Time Strategy (RTS), Sports and Simulation. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Conclusions</i> : RTS and Sports games are well-suited for concrete MAS problems such as multi-agent planning and task allocation. Expanding evidence and experimentation on other aspects related to scalability and usability issues is discussed. Those MAS problems and experiments that remain slightly modelled on games or are not thoroughly studied yet have been also identified.

Practical considerations regarding the implementation of economic sanctions by Swiss financial service providers

PurposeThe purpose of this paper is to discuss the practical problems which Swiss financial service providers face following the government’s decision to implement economic sanctions.Design/methodology/approachThe practical problems of implementation are based on the identified methods of circumvention in the first author’s empirical research on the mechanisms of money laundering.FindingsSecure anti-money laundering mechanisms promote the smooth implementation of sanctions. Despite the novelty of specific sanctions requirement, it is possible to have a supportive framework in place. Also, there remain a number of practical hurdles for Swiss banks to overcome, including the pressure on sanction alignment and the significant threat of noncompliance.Originality/valueThe sanctions imposed on Russia in 2022 are largely examined either from a broad political perspective or from the finite details of a business consultancy perspective. This paper aims to reconcile both perspectives to illustrate how the concrete problems of sanction implementation becomes evident in the wider political picture.

What’s the matter in education for sustainable development? How sustainability stories make matter matter as issues or problems

This study engages with how sustainability stories can assign meaning to sustainability matter in different ways. The study contributes to discussions on how to combine facts, norms, and the democratic action competence in pluralistic approaches in Environmental and Sustainability Education. A special focus is put on how co-created sustainability stories can be used to provide, explore, and expand shared experiences of sustainability. The analysis engages with how content is defined and made relevant through stories, how they represent matter as pre-defined problems and solutions or as an invitation to exploration and reinterpretation, and how competences for sustainable development are made visible through the characters. The method used is a holistic narrative content analysis of 21 sustainability stories, co-created by pre-school teachers and their children. Three selected stories exemplify the results and show how some stories manage to move back and forth between on the one hand assembling sustainability matter as concrete problems to be solved, and on the other hand as open-ended issues promoting critical reflection. The main conclusion is that these, promising but yet uncommon, stories best represent pluralistic perspectives, creativity, and democratic action competence.

Implementation of artificial intelligence to the prediction of the mechanical properties of concrete: A review

Artificial Intelligence is the simulation of human intellect by machines such as computer systems. Due to the lack of technology, the construction sector suffered from low productivity, time waste, poor product performance, and a lack of safety and security. The construction industry's use of artificial intelligence has risen and current challenges have been resolved. The article reveals that artificial Intelligence is utilized to monitor personnel, equipment, and construction-related mistakes. Major concrete problems include carbonation, reinforcing corrosion, chemical assault, and overloading which leads to strength reduction in concrete. The subfields of artificial intelligence, which include machine learning, knowledge-based systems, computer vision, robotics, and optimization, have been utilized to improve safety, security, quality, productivity, dependability, and precision. This study also describes the application of Artificial Intelligence to the assessment of mechanical properties of concrete. The main purpose of this article is to use artificial intelligence to monitor the structural health and mechanical characteristics of concrete. Concrete's health and safety are dependent on the subfields of artificial intelligence such as machine learning, computer vision, and knowledge-based systems. In line with this, the sensors were used to measure the health monitoring of concrete structures. These modern methods prevent workplace accidents leading to safety for the occupants in the workplace. This study also discusses mixture composition estimates to attain desired strength characteristics of the composite. The capacity to capture the physical and chemical processes of failure is also described in this study. This paper suggests that artificial intelligence in concrete is capable of monitoring the health of concrete. The technique has also been shown to accurately forecast the strength of concrete. This article also concludes that artificial intelligence can determine concrete's flexural strength and other attributes.

Penafsiran Al-Qur’an Perspektif Gus Dur dalam Buku Islam Ku, Islam Anda, Islam Kita

The interpretation of the modern-contemporary period focuses its interpretation on efforts to position the Qur'an as a book of guidance for humans, namely by prioritizing the "initial use" aspect of the Qur'an , namely to provide solutions to the concrete problems faced by Muslims. present time. There are not a few Indonesian national figures who have initiated Islamic reformist thoughts without leaving the historical and socio-cultural context that surrounds the Indonesian nation. One of these figures is KH. Abdurrahman Wahid or familiarly called Gus Dur. Although he did not leave much in the field of interpretation of the Qur'an, but it fulfills a number of aspects that are worthy and interesting to study. This research is completely methodological in the form of library research , namely a research system that uses data and information from various kinds of materials and literature. Like most character studies , this research uses qualitative research. Results from study this namely Gus Dur more many interpret verses of the Koran with use method ijmāli (global) and use ra`yu or analysis and his thoughts as source interpretation. However, there are sometimes Gus Dur use other verses of the Koran as well as hadith as source in interpreting the Qur'an, no seldom method interpretation thematic also used. Gus Dur's interpretation of Islamic verses and justice are still relevant to the current condition of society, which requires a role model in understanding the meaning of "justice" brought about by the Qur'an.

Karakteristik dan Corak Pemikiran Teologi Islam Klasik dan Modern

Classical theology is a legacy from past theologies in the span of Islamic history and has apologetic characteristics (long debates on the area of mortal sin, eschatology, heaven and hell and the eternity of the Qur'an) and romantic remembers and longs for the greatness and excellence of past theologians without filling and preparing for global competition to be faced, while the style of modern theological thinking is to prioritize substance rather than form, and function Islamic values to overcome concrete community problems such as ignorance, poverty, unemployment, and social backwardness and develop science and science within the framework of prosperity and the peace of mankind on this earth. The two theological styles that exist in society make the color of the paradigm of Islamic theology must be able to be dialecticized by adherents of more moderate theology, so that abandoning classical theology does not mean leaving totality but changing the construct of thinking towards the substance of ijtihad in accordance with messages of humanist values.

How tick list sustainability distracts from actual sustainable action: the UN 2030 Agenda for Sustainable Development

ABSTRACT The United Nations ‘Transforming our world: the 2030 Agenda for Sustainable Development’ lays out 17 Sustainable Development Goals to address a range of global issues related to the future of the planet and human well-being. Critics, however, argue that the Agenda, a complex product of multi-stakeholder governance, in its drive to accommodate many competing voices, is overloaded with weakly defined, overlapping and contradictory issues, concepts and buzzwords. These serve to gloss over actual concrete global problems and forces, concealing an underlying free-trade ideology. In this paper, using Multimodal Critical Discourse Analysis, we draw attention to the nature of the documents used to communicate the Agenda. These documents comprise an edifice of self-referential texts that rely heavily on infographics, bullet points, charts and tables. Such formats appear to helpfully simplify, distil information and break things down into workable components. But, we show, through the affordances of these formats, the the vagueness of buzzwords, contradictions and lack of clear causalities can be glossed over, presenting the Agenda as a highly technical, engaging, and above all moral process. These formats are important, therefore, for the legitimization and rhetorical power of the Agenda, necessary for its take-up by governments and organizations around the world.

Investasi Asing Dalam Pendirian PT Perorangan Ditinjau Dari UUPT Dan UU Cipta Kerja

The purpose of this study is to examine foreign investment owned by individual companies. This study uses normative legal research methods. Legal and conceptual approaches are the approaches used in this research. The collection of legal materials in this journal uses library research. The legal material analysis method used in this journal refers to deductive, namely drawing conclusions from a problem that is general in nature to the concrete problems faced. Namely explaining things that are general to matters that are specific in order to draw conclusions that can provide answers to the problem of this research, namely regarding investment in the establishment of individual PT in UUPT and UU Cipta Kerja. The results of this study show that after the promulgation of the Job Creation Law which changed several provisions in the Company Law, one of them introduced a new form of legal entity, namely an Individual Company which is specifically for MSEs with the aim of forming it to facilitate the development of micro and small businesses by being able to form legal entity business entities. only with 1 (one) founder or shareholder. Investment is basically an activity for a fairly long period of time, so that when investors' investment interest declines, the role of the government in inviting investors to invest in Indonesia will be able to help attract investors' interest and the impact will be felt when the process of economic activity has been running and there has been an increase in economic value.

ANALISIS KESULITAN BELAJAR BAHASA ARAB SISWA SMP IX PERGURUAN ISLAM MODERN AMANAH 1

Arabic is the language of the Qur'an and Hadith which is the source of Islamic law so without understanding it we will find it difficult to understand and understand the content of the Qur'an and Hadith, therefore one of the government policies under the auspices of the ministry of religion, Arabic is a compulsory subject that must be studied in Islamic educational institutions from exposure to Madrasah Ibtidaiyah to Islamic College. The type of research that the author used in this study is research field (field research), where this research is carried out to obtain data from concrete problems in the field in the form of sentence form information that gives an idea, attitude, and enthusiasm when participating in learning. The main source of data was obtained by making direct observations in the field, namely teachers and students of Modern Islamic School Amanah 1. The results of interviews of several students regarding the affective aspect (realm of taste) in Arabic learning can be interpreted as few of them have the ability to learn Arabic because some of them have low motivation in learning Arabic and most of them will learn when the next day there are assignments or daily tests or when told by their parents to research results, Data analysis and discussion about the analysis of the difficulty of learning Arabic at SMP 1 Amanah Medan can be concluded that the factors for students having difficulty learning Arabic include the lack of interest and motivation from within students to learn Arabic, the difficulty of reading and understanding the meaning of each Arabic vocabulary and the teacher's driving method that is too monotonous.

Exploring Exact Effects of Various Factors on Chloride Diffusion in Cracked Concrete: ABAQUS-Based Mesoscale Simulations

Chloride ion attack is a major cause of concrete durability problems, and existing studies have rarely addressed the effects of damage zones. In this paper, an improved mesoscale model including five phases was constructed using the finite element software ABAQUS to study the diffusivity of chloride ions in cracked concrete. It was found that the damage zone is negligible when the crack width is less than 50 μm, while the width and depth of the damage zone are about 15 times the crack width and 15% of the crack depth when the crack is greater than 50 μm. The results show that the diffusion of chloride is greatly influenced by the crack width, while it is little-influenced by the crack shape. Low water-cement ratio and adequate hydration of the concrete are also key factors affecting chloride diffusion. In contrast, regular rounded aggregates have a positive effect on reducing chloride diffusion compared to irregularly shaped aggregates, and this effect becomes weaker with increasing service time. In addition, the protective layer can effectively prevent the diffusion of chloride in concrete. Therefore, when designing marine concrete, efforts should be made to ensure that the concrete has a low water-cement ratio, adequate hydration, less cracking and a protective layer.

Meteorites in Physics Laboratory

A proposal for a physics laboratory inserted in an interdisciplinary learning path for characterizing meteorites is described. Small meteorites are characterized both qualitatively through magnetic properties and quantitatively with density measurements. Of particular interest is the open problem of measuring an object with a small volume and an irregular shape. From the measurements of immersion in water, which are often very difficult due to the lack of adequate instruments in laboratory, it is possible to face a concrete experimental problem that leads to unusual indirect measurements.

Brief Review on the Connection between the Micro-Canonical Ensemble and the Sq-Canonical Probability Distribution.

Non-standard thermostatistical formalisms derived from generalizations of the Boltzmann-Gibbs entropy have attracted considerable attention recently. Among the various proposals, the one that has been most intensively studied, and most successfully applied to concrete problems in physics and other areas, is the one associated with the Sq non-additive entropies. The Sq-based thermostatistics exhibits a number of peculiar features that distinguish it from other generalizations of the Boltzmann-Gibbs theory. In particular, there is a close connection between the Sq-canonical distributions and the micro-canonical ensemble. The connection, first pointed out in 1994, has been subsequently explored by several researchers, who elaborated this facet of the Sq-thermo-statistics in a number of interesting directions. In the present work, we provide a brief review of some highlights within this line of inquiry, focusing on micro-canonical scenarios leading to Sq-canonical distributions. We consider works on the micro-canonical ensemble, including historical ones, where the Sq-canonical distributions, although present, were not identified as such, and also more resent works by researchers who explicitly investigated the Sq-micro-canonical connection.

Strength and Workability of Concrete with Inclusion of Fly Ash, Quarry Dust and a Generic Naphthalene-based Super Plasticizer

Poor strength and workability often result in low quality concrete that can cause structural failures. This research work was conducted to improve the strength and workability of concrete at reduced amount of water due to the addition of super plasticizer by replacing partially the concrete materials: cement, with fly ash at 0%, 5%, 10% and 15%; fine aggregate, with quarry dust at 0% and 15%; and the addition of sulphonated Naphthalene Formaldehyde Condensate (SNFC) super plasticizer at 0% and 0.6% by weight of cement content reducing the amount of water to 0.45 w/c from the conventional 0.6 and 0.55 w/c ratio. Concrete cube specimens were prepared with these inclusions using grade M20 concrete and nominal mix proportion of 1:2:4. Sieve analysis test, specific gravity test, fineness test were carried out on the concrete materials, workability test was carried out on each concrete specimen, a compressive strength test and weight density test was done at 7days and 28days curing. The compressive strength of concrete made with fly ash, quarry dust and SNFC at 28days ranges from 19.58N/mm2 to 30.23N/mm2. These results were higher compared to those of conventional concrete. A combination of fly ash, quarry dust and SNFC was then recommended for solving problems of low-strength concrete.

PENINGKATAN KAPASITAS PUBLIC SPEAKING BAGI APARATUR PEMERINTAH DESA TANJUNG DAYANG SELATAN

Background: The ability to speak in public needs to be mastered by anyone, including village government officials. Not only the apparatus, all elements involved in the village including the Karang Taruna, the Village Representative Body, and the Empowerment and Family Welfare (PKK) of the village need to improve public speaking skills in order to strengthen the village's potential and self-potential. The absence of public speaking learning facilities in the village environment limits the local community's opportunities to develop public speaking skills. Purpose: Therefore, this community service activity aims to improve the public speaking skills of South Tanjung Dayang village apparatus, Indralaya Selatan District, Ogan Ilir Regency, South Sumatra Province. Method: This activity is aimed at village government officials which is carried out using three methods: lectures and questions and answers regarding the basic aspects of public speaking; problem solving by opening discussions about the participants' concrete problems when speaking and solutions to overcome them, as well as demonstrations and simulations. Result: This community service shows that this activity succeeded in increasing participants' understanding of important aspects of public speaking. This can be seen from the average score of the participants during the pre-test which increased from 69.2 with the lowest score of 35 to 85.6 with the lowest score of 65 during the post-test. Statistical analysis using the Wilcoxon test showed that the Sig. (2-tailed) of 0.000 &lt;0.05 which means the alternative hypothesis (Ha) that there is a significant difference between the average pre-test scores and post-test scores has been proven. This shows that public speaking training has a significant influence on increasing the understanding of the participants. Conclusion: The implementation of public speaking training for Tanjung Dayang Selatan village officials as a whole has been successful because there has been a significant increase in understanding.

Imaging Concrete Structures with Ultrasonic Shear Waves—Technology Development and Demonstration of Capabilities

Since 1987 when dry-point-contact (DPC) transducers were invented in the USSR, ultrasonic shear wave devices based on those transducers have been commercialized and have become one of the most effective technologies for imaging concrete. That said, the objectives of this paper are (1) to provide a brief review of the historical development of these powerful devices and (2) to provide a comprehensive assessment of their capabilities in imaging internal entities and structural defects. Regarding the former, the paper presents the context that gave birth to DPC technology and different generations of ultrasonic shear wave devices for concrete inspection. For the latter, one of the state-of-the-art ultrasonic shear wave devices (MIRA 3D) was used to collect data on concrete specimens with different built-in flaws/defects. Those data are then visualized with a commonly used data processing algorithm, the so-called synthetic aperture focusing technique (SAFT). Finally, based on the resulting images, the capabilities of the device are discussed in detail for each concrete imaging problem. A main limitation of ultrasonic shear wave technique for concrete inspection is that it requires a significant amount of time and effort for data collection.

Impact of High-Performance Expansion and Shrinkage-Reducing Agents on the Mechanical Properties and Shrinkage Compensation of High-Strength Concrete

A large number of binder ingredients such as cement and active mineral admixtures are used in the preparation of high-strength concrete, and the water:binder ratio is extremely low. This leads to a large amount of shrinkage of concrete at the early stage of curing, which poses a great threat to the safety and durability of the structure. To solve the cracking problem of high-strength concrete induced by high shrinkage, we choose to change the admixture to solve it. In this study, a high-performance expansion agent (HPEA) and shrinkage-reducing agent, which are currently studied in a small number, were selected by changing the way of admixture, and their effects on the strength and shrinkage of high-strength concrete were compared and analyzed. The results show that the addition of a HPEA is beneficial to the compressive strength of concrete and sufficient expansion can be obtained by using a high amount of HPEA, but there is an excessive and delayed expansion to produce cracks in the later stage. A shrinkage-reducing agent plays an adverse role in the development of concrete strength, but it performs better in inhibiting shrinkage. The combination of a HPEA and shrinkage reducing agent can largely avoid the formation of cracks, and the two have a certain synergy. The main reason is that a HPEA compensates for some of the negative effects of a shrinkage-reducing agent on concrete strength, and the shrinkage-reducing agent further strengthens the inhibition effect of a HPEA on concrete shrinkage, and to some extent avoids the risk of cracks caused by delayed expansion caused by admixture problems.

Effect of spent bleaching earth ash on sulphate attack resistance of concrete

One of the severe durability problems of concrete is sulphate attack. Sulphate attack can cause expansion of concrete due to the formation of gypsum and ettringite. Recently, spent bleaching earth ash (SBEA) is being used as a partial cement replacement in concrete. In this study, the effects of unground SBEA (USBEA) and ground SBEA (GSBEA) on sulphate attack resistance on concrete in terms of expansion of mortar bar and loss in compressive strength of concrete exposed to 5% sodium sulphate solution were determined. The SBEA was ground in a planetary grinding ball mill for 30 min to obtain a finer particle size. The expansion of mortar bars exposed to sulphate conditions containing USBEA and GSBEA was evaluated for 6 months according to ASTM C1012. Meanwhile, the compressive strength of concrete containing USBEA and GSBEA against sulphate attack was determined at 28 and 90 days. It was found that the expansion of mortar bars containing GSBEA was the lowest (0.01%) among the specimens. The strength deterioration factor of concrete containing GSBEA against sulphate attack was the lowest, with 1.31% at 90 days. The findings showed that ground SBEA could be used to enhance the sulphate attack resistance of concrete.