Hasil untuk "Environmental engineering"

Shengjie Ling, D. Kaplan, M. Buehler

Maher Abuhussain, Ali Hussain Alhamami, Khaled Almazam et al.

This study introduces a comprehensive framework combining building information modeling (BIM), project management body of knowledge (PMBOK), and machine learning (ML) to optimize energy efficiency and reduce environmental impacts in Riyadh’s construction sector. The suggested methodology utilizes BIM for dynamic energy simulations and design visualization, PMBOK for integrating sustainability into project-management processes, and ML for predictive modeling and real-time energy optimization. Implementing an integrated model that incorporates building-management strategies and machine learning for both commercial and residential structures can offer stakeholders a thorough solution for forecasting energy performance and environmental impact. This is particularly essential in arid climates owing to specific conditions and environmental limitations. Using a simulation-based methodology, the framework was evaluated based on two representative case studies: (i) a commercial complex and (ii) a residential building. The neural network (NN), reinforcement learning (RL), and decision tree (DT) were implemented to assess performance in energy prediction and optimization. Results demonstrated notable seasonal energy savings, particularly in spring (15% reduction for commercial buildings) and fall (13% reduction for residential buildings), driven by optimized heating, ventilation, and air conditioning (HVAC) systems, insulation strategies, and window configurations. ML models successfully predicted energy consumption and greenhouse gas (GHG) emissions, enabling targeted mitigation strategies. GHG emissions were reduced by up to 25% in commercial and 20% in residential settings. Among the models, NN achieved the highest predictive accuracy (R² = 0.95), while RL proved effective in adaptive operational control. This study highlights the synergistic potential of BIM, PMBOK, and ML in advancing green project management and sustainable construction.

Louafi Boutaina, Slimani Chaimae, Bessi Aymane et al.

Silybum marianum L. Gaertn is a spontaneous plant whose medicinal properties have been used for over two thousand years. This study aims to clarify the understanding and utilisation of S. marianum by the rural and urban populations of Ouezzane region in Morocco, in order to assess the level of recognition and exploitation of this plant. An ethnobotanical survey in this region involved a sample of 140 individuals. Survey results are analyzed using SPSS. The survey results have revealed a significantly limited level of appreciation for S. marianum. Through the use of chi-square statistical tests, we identified significant relationships between our variables and the knowledge about S. marianum and its use. Based on the findings of our study, Silybum marianum L. remains one of Morocco's most neglected and underutilized plants. This may be due to a lack of knowledge or adequate information about its applications, a lack of general interest or even socio-economic factors that limit its exploitation.

Yu Tan, Guangping Zhou, Huyuan Zhang et al.

Experiments were conducted to evaluate the healing of drying cracks in air-dried bentonite-sand blocks after hydration and swelling in groundwater, providing justifications to simplify the protection of blocks prior to installation in a high-level radioactive waste repository. Synthetic groundwater was prepared to represent the geochemistry of Beishan groundwater, and was used to hydrate the blocks during the swelling pressure and swelling strain measurements, as Beishan is the most promising site for China's repository. Healing of the surface cracks was recorded by photography, and healing of the internal cracks was visualized by CT images and hydraulic conductivity of air-dried blocks. The results indicate that the maximum swelling pressure and swelling strain are primarily affected by the geochemistry of Beishan groundwater, but not affected by the drying cracks. The maximum swelling pressure and swelling strain of air-dried blocks are comparable to or even higher than the pressure and strain of fresh blocks. The maximum swelling pressure measured in strong (i.e. high ion strength) Beishan groundwater was 44% of the pressure measured in deionized (DI) water, and the maximum swelling strain was reduced to 23% of the strain measured in DI water. Nevertheless, the remained swelling of the blocks hydrated in strong Beishan groundwater was sufficient to heal the surface and internal drying cracks, as demonstrated by the pictures of surface cracks and CT images. The hydraulic conductivity of the air-dried block permeated with strong groundwater was comparable (3.7× higher) to the hydraulic conductivity of the fresh block, indicating the self-healing of drying cracks after hydration and swelling in groundwater. A simplified method of protecting the block with plastic wraps before installation is recommended, since the remained swelling of the block hydrated in Beishan groundwater is sufficient to heal the drying cracks.

LI Yexin, LYU Gang, WANG Daohan et al.

【Objective】 Restoring coal mining waste dumps is a way to alleviate their detrimental impact on environment. In this paper, we present the results of an experimental study on distribution and stability of soil aggregates in a reclaimed coal mining overburden dump. 【Method】 The experiment was carried out at a reclaimed coal mine dump site in a grassland region in northern China. We measured the development of fissures from Zone I (GF) to Zone three (GFIII) in the fissure zone. The composition and distribution soil aggregates in these zones were determined using dry-wet sieve method. Aggregate stability and its relationship with the fissures was analyzed. 【Result】 The content of the >0.25 mm air-dried aggregates over the fissure zones was 23.02%~42.70%, and content of the >0.25 mm water-stable soil aggregates was 16.9%~29.52%. There was no significant difference between air-dried aggregates and water-stable aggregates. The content of the >0.25 mm water-stable soil aggregates in the 0~60 cm soil layer in GF, GFⅡ and GF Ⅲ was 25.26%, 26.57%, 23.62%, respectively, while the percentage of aggregate destruction in the three fissure zones was 20.77%~36.17%, 20.52%~25.00%, and 26.58%~40.56%, respectively. The percentage of aggregate destruction in 0~10, 10~20, 20~30, 30~40, 40~50, and 50~60 cm soil layers was 28.81%, 29.96%, 26.19%, 23.50%, 24.91%, and 29.38%, respectively. The fractal dimension of air-dried and water-stable soil aggregates was 2.847~2.919 and 2.898~2.942, respectively. Small aggregates and fine particles are the dominant aggregates. The mean mass diameter (MWD) and geometric mean diameter (GMD) of the air-dried aggregates in three fissure zones were 1.11, 1.05, 1.28 mm, and 0.45, 0.44, 0.49 mm, respectively. The MWD and GMD of water-stable soil aggregates in the three fissure zones were 0.67, 0.73, 0.72 mm, and 0.36, 0.38, 0.37 mm, respectively. Soil in GFⅡ had good structure and aggregate stability. Most of water-stable soil aggregates in the fissure zones were unstable due to the formation and development of fissures. 【Conclusion】 The formation and development of fissures in the reclaimed coal mining overburden dump reduced the stability of soil aggregates, thereby resulting in aggregate segmentation. The larger and wider the fissures were, the less stable the soil aggregates were.

Kai-Huang Chen, Chien-Min Cheng, Na-Fu Wang et al.

Activation energy, bipolar resistance switching behavior, and the electrical conduction transport properties of ITO_X:SiO₂ thin film resistive random access memory (RRAM) devices were observed and discussed. The ITO_X:SiO₂ thin films were prepared using a co-sputtering deposition method on the TiN/Si substrate. For the RRAM device structure fabrication, an Al/ITO_X:SiO₂/TiN/Si structure was prepared by using aluminum for the top electrode and a TiN material for the bottom electrode. In addition, grain growth, defect reduction, and RRAM device performance of the ITO_X:SiO₂ thin film for the various oxygen gas flow conditions were observed and described. Based on the <i>I-V</i> curve measurements of the RRAM devices, the turn on-off ratio and the bipolar resistance switching properties of the Al/ITO_X:SiO₂/TiN/Si RRAM devices in the set and reset states were also obtained. At low operating voltages and high resistance values, the conductance mechanism exhibits hopping conduction mechanisms for set states. Moreover, at high operating voltages, the conductance mechanism behaves as an ohmic conduction current mechanism. Finally, the Al/ITO_X:SiO₂/TiN/Si RRAM devices demonstrated memory window properties, bipolar resistance switching behavior, and nonvolatile characteristics for next-generation nonvolatile memory applications.

Bo Li, Ningjun Jiang, Xiaole Han

The Brillouin optical time domain reflectometry (BOTDR) system measures the distributed strain and temperature information along the optic fibre by detecting the Brillouin gain spectra (BGS) and finding the Brillouin frequency shift profiles. By introducing small gain stimulated Brillouin scattering (SBS), dynamic measurement using BOTDR can be realized, but the performance is limited due to the noise of the detected information. An image denoising method using the convolutional neural network (CNN) is applied to the derived Brillouin gain spectrum images to enhance the performance of the Brillouin frequency shift detection and the strain vibration measurement of the BOTDR system. By reducing the noise of the BGS images along the length of the fibre under test with different network depths and epoch numbers, smaller frequency uncertainties are obtained, and the sine-fitting R-squared values of the detected strain vibration profiles are also higher. The Brillouin frequency uncertainty is improved by 24% and the sine-fitting R-squared value of the obtained strain vibration profile is enhanced to 0.739, with eight layers of total depth and 200 epochs.

Charles Onyutha, Saeed Golian, Saeed Golian et al.

Antonio Stecco, Lorenza Bonaldi, Chiara Giulia Fontanella et al.

It is a common experience, reported by patients who have undergone manual therapy that uses deep friction, to perceive soreness in treatment areas; however, it is still not clear what causes it and if it is therapeutically useful or a simple side effect. The purpose of this narrative review is to determine whether manual and physical therapies can catalyze an inflammatory process driven by HA fragments. The literature supports the hypothesis that mechanical stress can depolymerize into small pieces at low molecular weight and have a high inflammatory capacity. Many of these pieces are then further degraded into small oligosaccharides. Recently, it has been demonstrated that oligosaccharides are able to stop this inflammatory process. These data support the hypothesis that manual therapy that uses deep friction could metabolize self-aggregated HA chains responsible for increasing loose connective tissue viscosity, catalyzing a local HA fragment cascade that will generate soreness but, at the same time, facilitate the reconstitution of the physiological loose connective tissue properties. This information can help to explain the meaning of the inflammatory process as well as the requirement for it for the long-lasting resolution of these alterations.

Zhihao FANG, Zhengquan LI, Mingwei ZHANG

In order to better implement the water environmental management policies, water quality evaluation is the basic step, that is to reasonably divide it into specific water quality category according to multiple water quality parameters in a certain water area.Aimed at this problem, an improved Naive Bayes classification method was proposed, which endowed different attributes with different weights, weakened the assumption of Naive Bayes conditional independence, and made the classification result closer to the actual category.Firstly, referred to the data released by the national surface water quality automatic monitoring station, 500 water quality data were selected as samples, and an evaluation system with four indicators was established, including dissolved oxygen, permanganate index, ammonia nitrogen and total phosphorus.And then, the improved Naive Bayes classification method was used to learn and evaluate the samples, and its classification performance by the five fold cross validation method was verified.The results show that the accuracy, precision, recall and F1 value of the improved Naive Bayes classification method reach 96.0%, 95.9%, 93.8% and 94.8% respectively, with higher performance index of water quality data classification compared with other Naive Bayes classification method, which can provide some reference for the problem of water quality data classification encountered in actual engineering.

Bo Wang, Hongxi Chen, Yibin Ao et al.

In order to support the green and low-carbon transformation of China’s construction industry and accomplish the dual carbon objective, it is vital to accelerate green technology innovation. Therefore, this paper takes the Chengdu–Chongqing urban agglomeration of China as the study area, using the super-efficiency slacks-based measure (SBM)model and the gravity model to assess the efficiency of green technology innovation in the construction industry, utilizing geographical detectors to investigate the drivers of green technology innovation in the construction industry further. Additionally, we consider each influencing factor’s level of impact on the efficiency of green technology innovation in the construction sector both under the single factor and double factor scenarios. The findings indicate that there is a considerable difference in the efficiency of green technology innovation in the Chengdu–Chongqing metropolitan agglomeration’s construction industry, and the trend is upward. In addition, the research area exhibited spatially heterogeneous characteristics in terms of the efficiency of green technology innovation in the construction industry, and the spatial spillover effect was significantly limited by distance. Further research revealed that environmental legislation, economic development, public environmental concern, urbanization level, and foreign direct investment were the primary driving factors of green technology innovation efficiency in the construction sector, and industrial size was the potential driving factor. The spatial and temporal differentiation of the green technology innovation efficiency in the construction industry was also more affected by the interaction between the dominating factor and the prospective factor than by either factor acting alone. The research’s findings are useful in advancing the green and low-carbon transformation of the construction sector in the Chengdu–Chongqing metropolitan agglomeration by offering theoretical support and decision-making reference.

Shiqin Yu, Shiqin Yu, Shiqin Yu et al.

Urbanization has induced substantial changes in soil physicochemical characteristic, which plays an important role in regulating soil fauna biodiversity in forests and grasslands. However, less is known about the urbanization effect on soil fauna biodiversity and how soil physicochemical changes mediate this effect. Along an urbanization gradient in the city of Guangzhou, we established four sites with different urbanization intensities, including an urban site, two suburban sites, and a rural site, and then studied their soil physicochemical characteristic and soil fauna biodiversity. The soil physicochemical characteristic dramatically changed along the urbanization gradient. In contrast, the soil fauna biodiversity exhibited a very different pattern. Soil fauna abundance was highest in the suburban sites. Moreover, there were significant changes of Pielou’s evenness and community structure in the suburban sites. Soil fauna biodiversity property in the urban site was similar to that in the rural site, except that the rural site was characterized by Enchytraeidae while the urban site was not characterized by any taxa. Our linear and canonical correspondence analysis models suggested that soil physicochemical characteristic only contributed a little to the variance of soil fauna abundance (19%), taxa number (27%), and community structure (12%). In contrast, soil physicochemical characteristic explained about half of the variance in Shannon’s diversity and Pielou’s evenness. However, with urbanization intensity increasing, soil physicochemical changes could both increase and decrease the diversity and evenness. Thus, our results revealed an inconsistent pattern between soil fauna biodiversity and soil physicochemical characteristic along an urbanization gradient. This study suggested that soil physicochemical change was less important as expected in regulating soil fauna biodiversity pattern under an urbanization context. To elucidate the effect of urbanization on soil fauna biodiversity, further studies should take other urbanization agents into account.

M. Heshmati, R. Haghani, M. Al‐Emrani

Xiaoqiang Yu, Qian Zhang, Xin Liu et al.

Solar interfacial evaporation, featured by high energy transfer efficiency, low cost, and environmental compatibility, has been widely regarded as a promising technology for solar desalination. However, the interplay between energy transfer and water transport in the same channels suggests that the tradeoff between high efficiency and long-term stability inherently exists in conventional photothermal nanomaterials. We summarize state-of-the-art research on various anti-salt clogging photothermal microstructures as long-term stable interfacial solar evaporators for solar desalination. The review starts with an overview of the current status and the fundamental limit of photothermal materials for solar desalination. Four representative strategies are analyzed in detail with the most recent experimental demonstrations, including fluid convection enhancement, surface wettability engineering, energy-mass-path decoupling, and surface chemistry engineering. Finally, this article focuses on the challenges in anti-salt clogging solar interfacial evaporators and potential point-of-use applications in the future.

L. J. E. Bouaziz, L. J. E. Bouaziz, F. Fenicia et al.

<p>Streamflow is often the only variable used to evaluate hydrological models. In a previous international comparison study, eight research groups followed an identical protocol to calibrate 12 hydrological models using observed streamflow of catchments within the Meuse basin. In the current study, we quantify the differences in five states and fluxes of these 12 process-based models with similar streamflow performance, in a systematic and comprehensive way. Next, we assess model behavior plausibility by ranking the models for a set of criteria using streamflow and remote-sensing data of evaporation, snow cover, soil moisture and total storage anomalies. We found substantial dissimilarities between models for annual interception and seasonal evaporation rates, the annual number of days with water stored as snow, the mean annual maximum snow storage and the size of the root-zone storage capacity. These differences in internal process representation imply that these models cannot all simultaneously be close to reality. Modeled annual evaporation rates are consistent with Global Land Evaporation Amsterdam Model (GLEAM) estimates. However, there is a large uncertainty in modeled and remote-sensing annual interception. Substantial differences are also found between Moderate Resolution Imaging Spectroradiometer (MODIS) and modeled number of days with snow storage. Models with relatively small root-zone storage capacities and without root water uptake reduction under dry conditions tend to have an empty root-zone storage for several days each summer, while this is not suggested by remote-sensing data of evaporation, soil moisture and vegetation indices. On the other hand, models with relatively large root-zone storage capacities tend to overestimate very dry total storage anomalies of the Gravity Recovery and Climate Experiment (GRACE). None of the models is systematically consistent with the information available from all different (remote-sensing) data sources. Yet we did not reject models given the uncertainties<span id="page1070"/> in these data sources and their changing relevance for the system under investigation.</p>

LALIT GOEL, Vijay Shankar, R. K. Sharma

Purpose Mulching is a practice recommended for soil moisture conservation in potato. The wheat straw and rice straw obtained as major crop residues were used as mulching materials to compare their effectiveness for soil moisture retention in potato crop. Methods The field experiments were conducted in a randomized complete block design replicated thrice with three treatments viz. plots incorporated with wheat straw mulch, rice straw mulch at the rate of 10 tons per hectare each and no mulch serving as control. The soil moisture was determined using a soil moisture probe and data were recorded daily at 10 cm, 20 cm and 30 cm soil depths. The Field Emission Scanning Electron Microscopy was used to investigate moisture retention characteristics of the mulch materials. Results Soil moisture retention varied as wheat straw mulch>rice straw mulch>no mulch at 10 cm, 20 cm and 30 cm soil depths, respectively. Highest moisture retention in wheat straw mulch at 10 cm depth is attributed to better moisture absorption ability of wheat straw in comparison to rice straw. Field Emission Scanning Electron Microscope images indicated the presence of smaller sized micro tubes in wheat straw than rice straw, which resulted in more water retention, thereby substantiating the findings of the study. Conclusion Wheat straw mulch is more effective than rice straw mulch for shallow rooted crops like potato, due to better moisture absorption and retention in upper soil layer.

Bo Wang, Yanhong Liu, Jinhui Hao et al.

Earth-abundant metal sulfides attracts large attention in recent years for hydrogen production via electrocatalytic water splitting. However, most works have been limited to the acidic condition, whereas the hydrogen evolution reaction (HER) in alkaline condition has rarely been discussed. Here we present an effective strategy for the growing of Co-Mo-S catalysts on carbon cloth via the controllable incorporation of cobalt into MoS2 with L-cysteine and phosphomolybdic acid to achieve the synergistic interaction of CoS2 and MoS2. The optimized Co-Mo-S catalysts (Co:Mo=1:2) showed a largely improved HER activity with an overpotential of 92 mV at current density of 10 mA cm-2 and Tafel slope of 82 mV dec-1. The origin of the activity enhancement was investigated through a series of characterizations, where the synergetic effect of the intrinsic fast HER kinetics of metallic CoS2 and the high active surface area of MoS2 plays a crucial role. With appropriate amount of cobalt, the Co-Mo-S catalysts show a relatively uniform distribution on the carbon cloth to ensure the large surface area, whereas excessive cobalt results in the formation of the large CoS2 particles with low HER activity from the low active surface area. Further electrochemical measurements demonstrated that the combination of larger exchange current density of CoS2 and the high electrochemical double–layer capacitance (proportional to the active surface area) of MoS2 together contributed to the HER activity enhancement of the Co-Mo-S catalysts. The Co-Mo-S/CC catalysts also show robust stability in alkaline solution. Our work provides a more profound understanding and an interesting view for the design of efficient ternary transition metal sulfide HER catalysts in alkaline condition by synergetic optimization of the intrinsic HER kinetics and the electrochemical active surface area.

Manuel de Jesús González Guillén

En México, han existido cuatro enfoques filosóficos de uso y aprovechamiento de los recursos forestales: el utilitarismo, el conservacionismo, el uso múltiple y el uso sustentable. Cada uno con una concepción diferente del papel que deben tener los recursos naturales y cómo ser aprovechados y administrados por sus dueños. La perspectiva utilitarista (1521-1950), se basó en lograr el bien individual y colectivo a través de la satisfacción de las necesidades humanas básicas, sin considerar la escasez de los recursos. Lo anterior tuvo consecuencias en la disminución y deterioro de los mismos, que se tradujo en descontentos y presiones sociales. Como resultado, el gobierno promovió un cambio de enfoque, y surgió el conservacionismo (1950 - 1970), el cual prohibió el uso y aprovechamiento de muchos de los bosques; con ello, se intentó que estos se recuperaran. Dicho enfoque logró lo contrario: cambios de uso de la tierra, incendios, sobrepastoreo, cortas clandestinas y un desinterés en el cultivo forestal. Criterios económicos característicos de los recursos como: utilidad, escasez, valor y disponibilidad en tiempo y forma, no fueron alcanzados.

G. Masters

A Meyer, R T R T Dobson

This paper considers the thermal design and the experimental testing of a heat pipe (thermosyphon) heat exchanger for a relatively small commercially available mini-drier. The purpose of the heat exchanger is to recover heat from the moist waste air stream to preheat the fresh incoming air. The working fluid used was R134a and the correlations are given for the evaporator and condenser inside heat transfer coefficients as well as for the maximum heat transfer rate. The theoretical model and computer simulation program used for the thermal design calculations are described. The validity of the as-designed and manufactured heat exchanger coupled to the drier is experimentally verified. The theoretical model accurately predicted the thermal performance and a significant energy savings and a reasonable payback period was achieved.