Search Results (189)

Land Value Capture (LVC) is increasingly being emphasized as a key mechanism for financing mass transit systems, promoted as a sustainability-oriented policy tool amid tightening public budgets. China has adopted a development-led approach to value capture through the “Rail plus Property (R + P)” model, drawing inspiration from the Hong Kong experience. The Shenzhen Metro’s “R + P” strategy has been widely acclaimed as the key to its reputation as “the only profitable transit company in mainland China without subsidies.” This paper questions this assumption and argues that the Shenzhen model is neither sustainable nor replicable, as its past performance depended on two exceptional conditions: an ascending phase of a real-estate cycle and unique institutional concessions from the central state. To substantiate this argument, we contrast Shenzhen’s value capture strategy with that of Nanjing—a provincial capital operating under routine institutional conditions, with governance and spatial structures broadly reflecting the prevailing urban development model in China. Using a comparative framework structured around three key dimensions of LVC—urban governance, risk management, and the transit company’s shift toward real estate—this paper reveals how distinct urban political economies give rise to contrasting value capture approaches: one expansionary, prioritizing short-term profit and rapid scale-up while downplaying risk management (Shenzhen); the other conservative, shaped by institutional constraints and characterized by reactive, incremental adjustments (Nanjing). These findings suggest that while LVC instruments offer valuable potential as a funding source for public transit, their long-term viability depends on early institutional embedding that aligns spatial, fiscal, and political interests, alongside well-developed project planning and capacity support in real estate expertise. Full article

Real-time train rescheduling is a widely used strategy to minimize knock-on delays in railway networks. While recent research has introduced intelligent solutions to railway traffic management, the tight interdependence of train timetables and the intrinsic complexity of railway networks have hindered the scalability of these approaches to large-scale systems. This paper proposes a multi-agent system (MAS) that addresses these challenges by decomposing the network into single-junction levels, significantly reducing the search space for real-time rescheduling. The MAS employs a Condorcet voting-based collaborative approach to ensure global feasibility and prevent overly localized optimization by individual junction agents. This decentralized approach enhances both the quality and scalability of train rescheduling solutions. We tested the MAS on a railway network in the UK and compared its performance with the First-Come-First-Served (FCFS) and Timetable Order Enforced (TTOE) routing methods. The computational results show that the MAS significantly outperforms FCFS and TTOE in the tested scenarios, yielding up to a 34.11% increase in network capacity as measured by the defined objective function, thus improving network line capacity. Full article

Mercury is naturally present in soils at trace concentrations, but its cycle is increasingly disrupted by anthropogenic activities, which affect its distribution and behavior. Due to its toxic nature, mercury has become a significant focus in environmental and public health policies. Following the detection of mercury anomalies during groundwater quality monitoring at the Pays de Caux study site (France), a comprehensive multidisciplinary research effort was initiated. This included geological and hydrogeological studies aimed at tracking mercury concentrations in piezometric wells and identifying the sources of these anomalies. This study seeks to assess the groundwater quality and characteristics from ten hydrogeological wells. The evaluation will focus on key hydrogeological parameters, including pH, redox potential (Eh), suspended solids, and groundwater levels, as well as a detailed geochemical analysis of elements such as Hg, Fe, Mn, Zn, Pb, and Cu. The mobilization of mercury and other metallic traces elements is strongly governed by environmental factors. Hydrochemical analyses highlight the complex interplay of various parameters that influence the chemical forms and behavior of mercury in both soil and groundwater. The results from the piezometric measurement campaigns (Pz1 to Pz7) have provided crucial insights, enabling the development of hypotheses about mercury’s behavior in the chalk aquifer. It is hypothesized that impermeable areas may trap groundwater for extended periods, leading to the accumulation and abnormal concentration of mercury. This could cause mercury to be intermittently released, potentially affecting the surrounding environment. Mercury concentrations in groundwater are highly sensitive to pH and redox potential (Eh), with low pH and reducing conditions promoting mercury mobilization and the formation of toxic methylated species. The study suggests the chalk aquifer is generally in equilibrium with mercury, but fluctuations in mercury levels between Pz7 and Pz4 are likely due to the heterogeneity of the clay and geological factors such as mineral composition and fracturing. This research provides insights into mercury transfer in heterogeneous environments and emphasizes the need for continuous hydrogeological monitoring, including piezometer readings, to manage mercury dispersion in the aquifer. Full article

Tannins are secondary metabolites naturally present in various plants as a defense mechanism. In animal nutrition, they play a dual role, acting as both antinutritional factors and bioactive agents, with potential benefits in nutrient metabolism and product quality. This meta-analysis aimed to evaluate the effects of dietary tannin on nutrient intake and digestibility, blood serum metabolite levels, growth performance, carcass characteristics, and meat quality in small ruminants. Ninety-seven studies were included in this meta-analysis. The effects of tannins were analyzed using a random-effects model to determine the weighted mean difference between treatments with tannins and the control (without tannins). Publication bias and heterogeneity between studies were explored, and meta-regression and subgroup analyses were performed. The results indicated that tannin significantly increased the intake of dry matter, crude protein, nitrogen (N), fecal N, and meat fatty acids (FA), such as C18:2 ω6, C18:3 ω3, C20:4 ω6, C20:5 ω3, total ω3 and ω6 FA, and total polyunsaturated FA (PUFA). However, NH₃-N, urinary N, blood urea nitrogen, cold carcass weight, subcutaneous fat thickness, drip loss, and nutrient digestibility decreased. In conclusion, tannin in small ruminants did not affect animal productivity and antioxidative status, but mainly modified nitrogen metabolism and improved the fatty acid profile of meat. Full article

The concept of the Condorcet winner has become central to most electoral models in the political economy literature. A Condorcet winner is the alternative preferred by a plurality in every pairwise competition; the notion of a k-winner generalizes that of a Condorcet winner. The k-winner is the unique alternative top-ranked by the plurality in every competition comprising exactly k alternatives (including itself). This study uses a spatial voting setting to characterize this theoretical concept, showing that if a k-winner exists for some $k>2$, then the same alternative must be the $k^{\prime }$-winner for every $k^{\prime }>k$. We derive additional results, including sufficient and necessary conditions for the existence of a k-winner for some $k>2$. Full article

The substantial volumes of tailings produced during ore beneficiation present significant challenges for sustainable management due to potential public health hazards, particularly from metal leaching. The risk associated with tailings varies greatly depending on their mineralogical composition and climatic conditions. If tailings are classified as a non-hazardous by-product, they may serve as secondary raw materials, offering a sustainable alternative to the reliance on non-renewable primary resources. In this study, the recycling feasibility of tailings from an active copper mine was assessed through mineralogical characterization, environmental tests (e.g., static, kinetic, and leaching tests), and geochemical modeling. This multi-faceted approach aimed to predict the geochemical behavior and reactivity of tailings under varying conditions. Results from the static tests indicated that the tailings were non-acid generating. Weathering cell tests revealed circumneutral pH conditions (6.5–7.8), low sulfide oxidation rates, and low instantaneous metal concentrations (<1 mg/L), except for copper (0.6–3.5 mg/L) and iron (0.4–1.4 mg/L). These conditions are attributed to the low abundance of sulfide minerals, such as pyrite, chalcopyrite, bornite, covellite (<0.1 wt.%), and chalcocite (0.2 wt.%), which are effectively encapsulated within gangue minerals. Additionally, the presence of neutralizing minerals, specifically dolomite (27.4 wt.%) and calcite (2.4 wt.%), further stabilizes pH and promotes metal sequestration in secondary mineral forms. The Toxicity Characteristic Leaching Procedure (TCLP) test confirmed low leachability, classifying the tailings as non-hazardous. Full article

This paper investigates active thermography models for non-destructive testing of composites, with a focus on continuous carbon fiber reinforced thermoplastic polymer (CCFRTP) components, in order to detect flaws such as porosity and delamination. The application of finite elements in this study with a numerical model of thermography focuses on collecting data, with critical points verified and validated by an experimental model. The study aims to understand the influence of different, independent parameters on the active thermography test, making it possible to develop optimized models. The numerical solution is close to the experimental results, indicating the potential to refine future experimental configurations. Full article

Additive manufacturing of advanced materials has become widespread, encompassing a range of materials including thermoplastics, metals, and ceramics. For the ceramics, the complete production process typically involves indirect additive manufacturing, where the green ceramic part undergoes debinding and sintering to achieve its final mechanical and thermal properties. To avoid unnecessary energy-intensive steps, it is crucial to assess the internal integrity of the ceramic in its green stage. This study aims to investigate the use of active thermography for defect detection. The approach is to examine detectability using two benchmarks: the first focuses on the detectability threshold, and the second on typical defects encountered in 3D printing. For the first benchmark, reflection and transmission modes are tested with and without a camera angle to minimize reflection. The second benchmark will then be assessed using the most effective configurations identified. All defects larger than 1.2 mm were detectable across the benchmarks. The method can successfully detect defects, with transmission mode being more suitable since it does not require a camera angle adjustment to avoid reflections. However, the method struggles to detect typical 3D-printing defects because the minimum defect size is 0.6 mm, which is the size of the nozzle. Full article

This study investigates the feasibility and effectiveness of two non-destructive testing methods, active thermography and shearography, on 3D-printed thermoplastic (TP) composites reinforced with continuous carbon fiber. Artificial defects were introduced into the composite plate to benchmark the detection capabilities of these non-destructive testing techniques (NDT). Active thermography produced a thermogram that highlighted defects through variations in surface temperature. Although effective for identifying defects ranging from 3 to 10 mm in size at four different depths, specifically 1 mm, 1.25 mm, 1.5 mm, and 1.75 mm, through the thickness of a 2.8 mm plate, the method encountered some limitations. It faced challenges in detecting deeper defects and accurately determining their shapes. Shearography, which utilizes fringe pattern distortions to detect surface displacement anomalies, successfully identified near-surface defects within the same size range. However, it required more expertise for accurate interpretation and struggled with detecting smaller and deeper defects. The complementary strengths and limitations of these methods suggest that employing both could offer a more comprehensive solution for defect detection in 3D-printed TP composites. Full article

Advancements in blockchain technology and network technology are bringing in a new era in electronic voting systems. These systems are characterized by enhanced security, efficiency, and accessibility. In this paper, we compose a comparative analysis of blockchain-based electronic voting (e-voting) systems using blockchain technology, cryptographic techniques, counting methods, and security requirements. The core of the analysis involves a detailed examination of blockchain-based electronic voting systems, focusing on the variations in architecture, cryptographic techniques, vote counting methods, and security. We also introduce a novel blockchain-based e-voting system, which integrates advanced methodologies, including the Borda count and Condorcet method, into e-voting systems for improved accuracy and representation in vote tallying. The system’s design features a flexible and amendable blockchain structure, ensuring robustness and security. Practical implementation on a Raspberry Pi 3 Model B+ demonstrates the system’s feasibility and adaptability in diverse environments. Our study of the evolution of e-voting systems and the incorporation of blockchain technology contributes to the development of secure, transparent, and efficient solutions for modern democratic governance. Full article

This paper foccusses on the Tangwang language, a Chinese variety spoken in southern Gansu that has been in contact with the Dongxiang language, a Mongolic language. Tangwang is believed to be a highly altaicised variety, as it demonstrate several traits that are usually absent in this language family are are reputed ‘typical’ of the Turkic-Mongolic languages. However, most of these traits are present in the other northwestern chinese varieties and are the result of reanalysis, thus, it is difficult to trace their exact origin. This paper aims at analyzing the influence of Mongolic languages on Tangwang from the perspective of borrowings, and in particular direct loans. Taking the formally identical features that are shared in Dongxiang and Tangwang as a starting point, we will try to determine which form can be seen as a direct borrowing due to the adstratal influence of Dongxiang and which one is probably due to an earlier altaic influence. We will try to classify which form is a ‘true’ direct loan from Dongxiang and which form could be the evidence of an earlier substrate. From the results, and based on the existing models on languages contact, we will try to understand which mechanisms from relexification, grammaticalization, and language shift is the most probable in the case of Tangwang. Full article

The decontamination of polluted soils is a major socioeconomic issue in many industrialized countries. In situ remediation approaches are nowadays preferred to ex situ techniques, but they require among others the use of bioindicators, which are sensitive to the progressive depollution on health effects. Animal species have been mainly used so far to monitor aquatic and air pollution. Current research focuses on the development of living indicators of soil pollution. In this study, the garden snail Helix aspersa maxima was acutely exposed to cadmium, one major soil contaminant causing severe health effects, including nephrotoxicity. Kidney and hemolymph were sampled and analyzed by a ¹H-NMR-based metabonomic approach. Shortly after Cd exposure, numerous metabolic changes occurred in the hemolymph and kidney extracts. Altogether, they were indicative of a switch in energy sources from the Krebs cycle towards b-oxidation and the utilization of stored galactogen polysaccharides. Then, the activation of antioxidant defenses in the renal cells was suggested by the alteration in some precursors of glutathione synthesis, such as glutamate, and by the release of the antioxidant anserin. Cell membrane damage was evidenced by the increased levels of some osmolytes, betaine and putrescine, as well as by a membrane repair mechanism involving choline. Finally, the development of metabolic acidosis was suggested by the elevation in 3-HMG in the hemolymph, and the more pronounced lysine levels were consistent with acute excretion troubles. Cd-induced renal damage was objectified by the increased level of riboflavin, a recognized biomarker of nephrotoxicity. Full article

The interconnection between engineering simulations, real-world experiments, and virtual reality remains underutilised in engineering. This study addresses this gap by implementing such interconnections, focusing on active thermography for a carbon fibre plate in the aerospace domain. Six scenarios based on three parameters were simulated using ComSol Multiphysics 6.2 and validated experimentally. The results were then integrated into a virtual reality serious game developed with Unreal Engine 5.3.2 and aimed at educating users on thermography principles and aiding rapid experimental condition analysis. Users are immersed in a 3D representation of the research laboratory, allowing interaction with the environment, understanding thermographic setups, accessing instructional videos, and analysing results as graphs or animations. This serious game helps users determine the optimal scenario for a given problem, enhance thermography principle comprehension, and achieve results more swiftly than through real-world experimentation. This innovative approach bridges the gap between simulations and practical experiments, providing a more engaging and efficient learning experience in engineering education. It highlights the potential of integrating simulations, experiments, and virtual reality to improve understanding and efficiency in engineering. Full article