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Publications - 6374

SCHEDULING OF WASTE WOOD PROCESSING FACILITIES WITH OVERLAPPING JOBS

No authors available

Publication Name: Proceedings of the 16th International Symposium on Operational Research in Slovenia, SOR 2021

Publication Date: 2021-01-01

Volume:

Issue:

Page Range: 321-326

Description:

An important phase in most waste wood value chains is the processing of bulk waste from various sources, usually by means of shredding. This paper presents a method for scheduling the machines in such a waste wood processing facility, where incoming deliveries of different types of wood are processed by a series of treatment and transformation steps to produce shredded wood. A mathematical model is presented for the problem, that allows overlaps between consecutive steps to optimize resource flow through the system. The efficiency of the model is presented on randomly generated instances.

Open Access: No

DOI: DOI not available

The Road Pavement Structure as a Forgotten Element of the Transport Infrastructure System

Publication Name: Lecture Notes in Networks and Systems

Publication Date: 2025-01-01

Volume: 1258 LNNS

Issue: Unknown

Page Range: 248-262

Description:

Despite rapid advancements in vehicle and human integration within road transport systems, the role of road pavement structures has been largely overlooked. This paper is motivated by the critical need to address this gap, particularly in light of the growing challenges posed by global climate change. The road transport system, as an integrated “human-vehicle-road” unit placed within the environment, has undergone significant changes to this day. However, this rapid development has been predominantly confined to two elements of the system: humans and vehicles. Vehicles and their drivers are receiving increasingly specific and targeted information about traffic processes, and the role of humans in processing this information is progressively being assumed by vehicle intelligence. As a result, humans and vehicles, as system components, are becoming increasingly integrated. As an innovation in infrastructure, the road pavement structure has largely been unaffected by current developments in material technology and vehicle advancements, with no significant breakthroughs beyond typical alternatives to asphalt or concrete pavements. This article explores whether the presumed future impact of global climate instability might reshape the developmental trajectories of certain elements of the road transport system and whether the need to address weather extremes could bring research related to the resilience and climate adaptation potential of road pavement structures to the forefront, potentially at the expense of the vehicle and driver, the other two system elements.

Open Access: Yes

DOI: 10.1007/978-3-031-81799-1_23

Controller design of DC/DC buck converter based on feedback linearization with integrator

Publication Name: Gpmc 2020 2nd IEEE International Conference on Gridding and Polytope Based Modeling and Control Proceedings

Publication Date: 2020-11-19

Volume: Unknown

Issue: Unknown

Page Range: 35-38

Description:

The paper presents the feedback linearization technique of voltage mode DC/DC buck converter. The nonlinear state-space model is presented and has been stabilized by pole placement technique and finally the voltage control of output has been realized by integral control. The designed controller has been simulated by MATLAB. Results are shown that the developed controller has good dynamic and static behavior.

Open Access: Yes

DOI: 10.1109/GPMC50267.2020.9333821

Probabilistic Topology Optimization of Steel I-Beam Web Configurations Under Varied Load Positions

Publication Name: Advances in Transdisciplinary Engineering

Publication Date: 2024-01-01

Volume: 59

Issue: Unknown

Page Range: 30-36

Description:

This study investigates the impact of uncertain load positions through an innovative optimization technique. It seamlessly integrates reliability-based design into the optimization of the structural topology, with a specific focus on the web portion of steel I-beams and including geometrical imperfection analysis. The study operates under the premise that the applied load is randomly positioned, engaging in a comprehensive probabilistic analysis. This methodology extends its considerations to additional factors, such as material properties, volume fraction, and geometric imperfections. The assumption of a normal distribution for each of these parameters aids in quantifying uncertainties. Moreover, the proposed work leverages the notion of plastic ultimate load multipliers to illustrate how the algorithm can improve the performance of steel beams. To evaluate the algorithm, the results of a benchmark problem were meticulously analyzed. While exploring the probabilistic nature of externally applied force positions, a numerical example was conducted involving a steel I-beam within the context of reliability-based imperfect geometry topology optimization. The outcomes of the proposed method underscore that the integration of probabilistic design significantly influences the topology optimization process.

Open Access: Yes

DOI: 10.3233/ATDE240523

Prediction of Scour Depth for Diverse Pier Shapes Utilizing Two-Dimensional Hydraulic Engineering Center’s River Analysis System Sediment Model

Publication Name: Fluids

Publication Date: 2024-11-01

Volume: 9

Issue: 11

Page Range: Unknown

Description:

Examining scouring around bridge piers is crucial for ensuring water-related infrastructure’s long-term safety and stability. Accurate forecasting models are essential for addressing scour, especially in complex water systems where traditional methods fall short. This study investigates the application of the HEC-RAS 2D sedimentation model, which has recently become available for detailed sediment analysis, to evaluate its effectiveness in predicting scoring around various pier shapes and under different water conditions. This study offers a comprehensive assessment of the model’s predictive capabilities by focusing on variables such as water velocity, shear stress, and riverbed changes. Particular attention was paid to the influence of factors like floating debris and different pier geometries on scour predictions. The results demonstrate that while the HEC-RAS 2D model generally provides accurate predictions for simpler pier shapes—achieving up to 85% precision—it shows varied performance for more complex designs and debris-influenced scenarios. Specifically, the model overpredicted scouring depths by approximately 20% for diamond-shaped piers and underpredicted by 15% for square piers in debris conditions. Elliptical piers, in contrast, experienced significantly less erosion, with scour depths up to 30% shallower compared to other shapes. This study highlights the novel application of the HEC-RAS 2D model in this context and underscores its strengths and limitations. Identified issues include difficulties in modeling water flow and debris-induced bottlenecks. This research points to the improved calibration of sediment movement parameters and the development of advanced computational techniques to enhance scour prediction accuracy in complex environments. This work contributes valuable insights for future research and practical applications in civil engineering, especially where traditional scour mitigation methods, such as apron coverings, are not feasible.

Open Access: Yes

DOI: 10.3390/fluids9110247

Study of Bonding between Façade Stones and Substrates with and without Anchorage Using Shear-Splitting Test—Case Study: Travertine, Granite, and Marble

Publication Name: Buildings

Publication Date: 2023-05-01

Volume: 13

Issue: 5

Page Range: Unknown

Description:

This paper presents an investigation into the bond strength of three common façade stones, namely, travertine, granite, and marble, to a concrete substrate using a shear-splitting test. The effects of anchorage, the number of curing days, and the presence of an anti-freezing agent in cement–sand mortar on bond strength were studied. The results show that the number of curing days had a significant impact on the bond strength between the stones and the substrates. The presence of an anti-freezing agent and accelerator increased bonding during the initial days, but this effect gradually decreased. The use of anchorage had a positive effect on the bond strength, particularly with fewer curing days. Granite had the lowest bond strength when no anchorage was used due to its low permeability. Based on the findings, a novel fuzzy logic approach was proposed to predict the bond strength. This study provides valuable insights into improving the bonding of façade stones to substrates and can aid in the safe and efficient use of these materials in construction.

Open Access: Yes

DOI: 10.3390/buildings13051229

On the vertex degree indices of connected graphs

Publication Name: Chemical Physics Letters

Publication Date: 2011-08-25

Volume: 512

Issue: 4-6

Page Range: 283-286

Description:

We introduce a family of invariants defined in terms of positive functions of degrees of vertices in a graph. A member of the family that measures the average degree of neighbors of vertices in a graph is then investigated for the predictive potential for stability in the class of generalized fullerenes. © 2011 Elsevier B.V. All rights reserved.

Open Access: Yes

DOI: 10.1016/j.cplett.2011.07.040

Green manufacturing practices and sustainable performance among Ghanaian manufacturing SMEs: the explanatory link of green supply chain integration

Publication Name: Management of Environmental Quality an International Journal

Publication Date: 2020-10-16

Volume: 31

Issue: 6

Page Range: 1457-1475

Description:

Purpose: The aim of this study is to examine the explanatory link of green supply chain integration (GSCI) between green manufacturing practices (GMPs) and sustainable performance (economic [EP], environmental [EnP] and social [SP] performances) by using data from an emerging country. Design/methodology/approach: An explanatory research design was employed for the study. Structured questionnaires were used to collect data from 178 Ghanaian manufacturing small and medium-sized enterprises (SMEs). Hypotheses were formulated and tested using partial least square structural equation modeling (PLS-SEM). Findings: The results indicate that GMPs have a significant positive effect on sustainable performance (EP, EnP and SP). Again, GMPs have a significant positive effect on GSCI. Additionally, GSCI plays a mediating role between green manufacturing practices and sustainable performance. Research limitations/implications: In this study, GSCI was compositely measured despite having three dimensions. Generalizing the findings is also not guaranteed since the sample constitutes Ghanaian manufacturing SMEs. Practical implications: The results provide significant ramifications for managers of manufacturing SMEs within Ghana and those in other sub-Saharan African context. Based on the results, managers of manufacturing firms will have stronger backing to invest in GMPs, while at the same time establish strong ties with eco-oriented supply chain partners so as to achieve their sustainable performance goals. Originality/value: This study adds to the literature in the area of sustainability and triple bottom line by providing evidence from a fast growing industrialized and emerging country.

Open Access: Yes

DOI: 10.1108/MEQ-01-2020-0019

Criticality analysis of purchased materials based on fuzzy signatures

Publication Name: IEEE International Conference on Fuzzy Systems

Publication Date: 2017-08-23

Volume: 0

Issue: Unknown

Page Range: Unknown

Description:

Selecting and evaluating the suppliers represent a very complex task, because a wide range of attributions must be taken into consideration and many of them are difficult to be made objectively quantified. The aim of this research is to provide a new model based on fuzzy signatures for selecting and evaluating the critical parts for the production.

Open Access: Yes

DOI: 10.1109/FUZZ-IEEE.2017.8015649