To solve the problem of long response time when users obtain suitable cutting parameters through the Internet based platform,a case-based reasoning framework is proposed.Specifically,a Hamming distance and Euclidean d...To solve the problem of long response time when users obtain suitable cutting parameters through the Internet based platform,a case-based reasoning framework is proposed.Specifically,a Hamming distance and Euclidean distance combined method is designed to measure the similarity of case features which have both numeric and category properties.In addition,AHP(Analytic Hierarchy Process)and entropy weight method are integrated to provide features weight,where both user preferences and comprehensive impact of the index have been concerned.Grey relation analysis is used to obtain the similarity of a new problem and alternative cases.Finally,a platform is also developed on Visual Studio 2015,and a case study is demonstrated to verify the practicality and efficiency of the proposed method.This method can obtain cutting parameters which is suitable without iterative calculation.Compared with the traditional PSO(Particle swarm optimization algorithm)and GA(Genetic algorithm),it can obtain faster response speed.This method can provide ideas for selecting processing parameters in industrial production.While guaranteeing the characteristic information is similar,this approach can select processing parameters which is the most appropriate for the production process and a lot of time can be saved.展开更多
Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate ...Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.展开更多
In a study published in Nature Catalysis on May 28,Chinese scientists unveiled a nove l approach to transforming lignin,a major component of woody biomass,into valuable chemical products(doi:10.1038/s41929-024-01165-w...In a study published in Nature Catalysis on May 28,Chinese scientists unveiled a nove l approach to transforming lignin,a major component of woody biomass,into valuable chemical products(doi:10.1038/s41929-024-01165-w).This discovery could pave the way for more sustainable and efficient use of renewable resources.展开更多
This article proposes an integral-based event-triggered attack-resilient control method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception att...This article proposes an integral-based event-triggered attack-resilient control method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception attacks. First, a novel AoG synergistic turning model is established with synergistic reverse steering of the front and main wheels to decrease the steering angle of the AoG fuselage, thus reducing the steady-state error when it follows a path with some large curvature. Considering that the tire cornering stiffness of the front and main wheels vary during steering, a dynamical observer is designed to adaptively identify them and estimate the system state at the same time.Then, an integral-based event-triggered mechanism(I-ETM) is synthesized to reduce the transmission frequency at the observerto-controller end, where stochastic deception attacks may occur at any time with a stochastic probability. Moreover, an attackresilient controller is designed to guarantee that the closed-loop system is robust L2-stable under stochastic attacks and external disturbances. A co-design method is provided to get feasible solutions for the observer, controller, and I-ETM simultaneously. An optimization program is further presented to make a tradeoff between the robustness of the control scheme and the saving of communication resources. Finally, the low-and high-probability stochastic deception attacks are considered in the simulations. The results have illustrated that the AoG synergistic turning system with the proposed control method follows a path with some large curvature well under stochastic deception attacks. Furthermore,compared with the static event-triggered mechanisms, the proposed I-ETM has demonstrated its superiority in saving communication resources.展开更多
The interaction between light and temperature is known to influence the seasonal growth of trees.Traditional studies on"light"primarily focus on day length,specifically short day(SD)or long day(LD)conditions...The interaction between light and temperature is known to influence the seasonal growth of trees.Traditional studies on"light"primarily focus on day length,specifically short day(SD)or long day(LD)conditions.However,little research has been conducted on the process of transitioning between SD and LD conditions.展开更多
Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Adva...Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Advances in the understanding of entomophagy and animal nutrition over the past decades have propelled research areas toward testing multiple aspects of YML to exploit them better as animal feed sources. This review aims to summarize various approaches that could be exploited to maximize the nutritional values of YML as an animal feed ingredient. In addition, YML has the potential to be used as an antimicrobial or bioactive agent to improve animal health and immune function in production animals. The dynamics of the nutritional profile of YML can be influenced by multiple factors and should be taken into account when attempting to optimize the nutrient contents of YML as an animal feed ingredient. Specifically, the use of novel land-based and aquatic feeding resources, probiotics, and the exploitation of larval gut microbiomes as novel strategies can assist to maximize the nutritional potential of YML. Selection of relevant feed supplies, optimization of ambient conditions, the introduction of novel genetic selection procedures, and implementation of effective post-harvest processing may be required in the future to commercialize mealworm production. Furthermore, the use of appropriate agricultural practices and technological improvements within the mealworm production sector should be aimed at achieving both economic and environmental sustainability. The issues highlighted in this review could pave the way for future approaches to improve the nutritional value of YML.展开更多
The multi-pass turning operation is one of the most commonly used machining methods in manufacturing field.The main objective of this operation is to minimize the unit production cost.This paper proposes a Gaussian qu...The multi-pass turning operation is one of the most commonly used machining methods in manufacturing field.The main objective of this operation is to minimize the unit production cost.This paper proposes a Gaussian quantum-behaved bat algorithm(GQBA)to solve the problem of multi-pass turning operation.The proposed algorithm mainly includes the following two improvements.The first improvement is to incorporate the current optimal positions of quantum bats and the global best position into the stochastic attractor to facilitate population diversification.The second improvement is to use a Gaussian distribution instead of the uniform distribution to update the positions of the quantum-behaved bats,thus performing a more accurate search and avoiding premature convergence.The performance of the presented GQBA is demonstrated through numerical benchmark functions and amulti-pass turning operation problem.Thirteen classical benchmark functions are utilized in the comparison experiments,and the experimental results for accuracy and convergence speed demonstrate that,in most cases,the GQBA can provide a better search capability than other algorithms.Furthermore,GQBA is applied to an optimization problem formulti-pass turning,which is designed tominimize the production cost while considering many practical machining constraints in the machining process.The experimental results indicate that the GQBA outperforms other comparison algorithms in terms of cost reduction,which proves the effectiveness of the GQBA.展开更多
With the increasing use of difficult-to-machine materials in aerospace applications,machining requirements are becoming ever more rigorous.However,traditional single-point diamond turning(SPDT)can cause surface damage...With the increasing use of difficult-to-machine materials in aerospace applications,machining requirements are becoming ever more rigorous.However,traditional single-point diamond turning(SPDT)can cause surface damage and tool wear.Thus,it is difficult for SPDT to meet the processing requirements,and it has significant limitations.Research indicates that supplementing SPDT with unconventional techniques can,importantly,solve problems due to the high cutting forces and poor surface quality for difficult-to-machine materials.This paper first introduces SPDT and reviews research into unconventional techniques for use with SPDT.The machining mechanism is discussed,and the main advantages and disadvantages of various methods are investigated.Second,hybrid SPDT is briefly described,which encompasses ultrasonic-vibration magnetic-field SPDT,ultrasonic-vibration laser SPDT,and ultrasonic-vibration cold-plasma SPDT.Compared with the traditional SPDT method,hybrid SPDT produces a better optical surface quality.The current status of research into unconventional techniques to supplement SPDT is then summarized.Finally,future development trends and the application prospects of unconventional assisted SPDT are discussed.展开更多
This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse ...This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities.展开更多
A novel method for designing chalcogenide long-period fiber grating(LPFG) sensors based on the dual-peak resonance effect of the LPFG near the phase matching turning point(PMTP) is presented. Refractive index sensing ...A novel method for designing chalcogenide long-period fiber grating(LPFG) sensors based on the dual-peak resonance effect of the LPFG near the phase matching turning point(PMTP) is presented. Refractive index sensing in a high-refractive-index chalcogenide fiber is achieved with a coated thinly clad film. The dual-peak resonant characteristics near the PMTP and the refractive index sensing properties of the LPFG are analyzed first by the phase-matching condition of the LPFG. The effects of film parameters and cladding radius on the sensitivity of refractive index sensing are further discussed. The sensor is optimized by selecting the appropriate film parameters and cladding radius. Simulation results show that the ambient refractive index sensitivity of a dual-peak coated thinly clad chalcogenide LPFG at the PMTP can be 2400 nm/RIU, which is significantly higher than that of non-optimized gratings. It has great application potential in the field of chemical sensing and biosensors.展开更多
This paper presents the results of experimental work carried out in dry turning of cast duplex stainless steels (ASTM A 995 Grade4A and ASTM A 995 Grade5A) using TiC and TiCN coated cemented carbide cutting tools. The...This paper presents the results of experimental work carried out in dry turning of cast duplex stainless steels (ASTM A 995 Grade4A and ASTM A 995 Grade5A) using TiC and TiCN coated cemented carbide cutting tools. The turning tests were conducted at five different cutting speeds (80, 100, 120, 140 and 160 m/min) and three different feed rates (0.04, 0.08 and 0.12 mm/rev) with a constant depth of cut (0.5 mm). The influence of cutting speed and feed rate on the machined surface roughness was investigated. Texture analysis (Bulk) was also carried out to study the impact of preferred orientation on the resulting surface roughness. The result reveals that the increasing cutting speed decreases the surface roughness till a particular point and then increases whereas;the surface roughness value decreases with the decreasing feed rate. Presence of alpha fiber (Bulk texture analysis) in the austenite phase of 4A work piece material leads to better surface finish. Among both the grades, surface finish of grade 4A is better than grade 5A work piece material.展开更多
The U.S.dollar has long stood tall as the pre-eminent global currency for international cross-border trade settlements and foreign exchange reserves ever since the launch of the Bretton Woods institutions-Internationa...The U.S.dollar has long stood tall as the pre-eminent global currency for international cross-border trade settlements and foreign exchange reserves ever since the launch of the Bretton Woods institutions-International Monetary Fund(IMF)and World Bank(WB).展开更多
Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on...Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on optical surfaces, which can have unpredictable adverse effects on imaging. In order to predict the effect of turning marks diffraction on the degradation of imaging quality, a model of the influence of SPDT processing parameters on the reduction of system imaging MTF under the influence of ideal grating turning marks diffraction was established. The results show that the depth of the turning mark will lead to the decline of MTF, especially the low frequency information. Finally, a method is proposed to reduce the effect of turning marks diffraction through changing the processing parameters. .展开更多
Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to ...Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to 6 months of age to EBF until about 6 months of age, with the addition of complementary foods thereafter. This recommendation confirms that breast milk alone is sufficient to meet infants’ nutritional requirements for the first 6 months of life. The main objective of this study was to investigate the effect of various feeding practices on the Nutritional status of infants 0 - 12-month-old in the Kumba 1 Sub-Division. A descriptive cross-sectional study was conducted from December 2019 to August 2020. A total of 341 nursing mothers and their infants 0 - 12 months of age were recruited. Socio-demographic factors and the different feeding habits of the children were assessed using a semi-structured questionnaire. Nutritional status was assessed using anthropometric measurements. The overall proportion of infants who exclusively breastfed for 6 months was 69.2% and those who were mix-fed were 30.8% in the study area. The overall prevalence of malnutrition in the population was 61.0%. Among the malnourished children, 53.1% were underweight, 19.6% were wasted and 10.0% were stunted. Though not significant, the prevalence of wasting (21.0%) and underweight (58.3%) was higher among Mix-Fed (MF) children when compared to their EBF counterparts. Feeding practices affected the nutritional status of the infants. Underweight and wasting were observed among infants on Complementary Feeding (CF), although some exclusively breast-fed infants were stunted. Hence, nursing mothers should try as much as possible to practice EBF as recommended by WHO and can practice CF when the child is above six months.展开更多
Research using open-circuit respiration chambers has established that Asparagopsis bioactive compounds stabilized in canola oil (Asp-Oil), delivering a range of inclusion between 34 - 51 mg bromoform (CHBr3)/kg dry ma...Research using open-circuit respiration chambers has established that Asparagopsis bioactive compounds stabilized in canola oil (Asp-Oil), delivering a range of inclusion between 34 - 51 mg bromoform (CHBr3)/kg dry matter intake (DMI), inhibits methane (CH4) emissions > 98% in feedlot cattle. In this study, Asp-Oil was fed at 35 mg CHBr3/kg DMI in the feedlot finisher diet under highly replicated and commercially relevant conditions, and adequately powered to confirm differences as low as 3.3% in feed conversion efficiency (FCE). The study also evaluated the effect of Asp-Oil on CH4 production (g/day), carcass and meat-eating qualities, animal health, and food safety. The experiment consisted of 300 Angus-Shorthorn (Bos taurus) steers in 30 pens of 10 and fed a barley-based ration supplemented with canola oil (Control, n = 15), or Asp-Oil (n = 15) for total 81-d, inclusive of 21-d transition to full Asp-Oil and grain inclusion in the finisher ration. Reduction of CH4 was measured using GreenFeed Emissions Monitors (GEM) in a subset of 2 pens in both Control and Asp-Oil. However, 67% of CH4 measurements were recorded below the GEM’s limit of detection. An inhibition range of 58% - 98% was demonstrated by collectively using GEM and preliminary respiration chamber measurements. Asp-Oil improved FCE 7.4% in the finisher diet, and 5.6% across transition and finisher periods. During the transition steps the steers had not yet received their full allocations of grain and Asp-Oil which is responsible for the lower FCE benefits. A 4.1% lower DMI in the finisher period contributed to benefits in FCE with no effect on daily weight gains. Cost of feed and weight gain were reduced $0.35/head/day and $0.23/kg, respectively, in steers receiving Asp-Oil. Residues of Asparagopsis CHBr3 were not detected in any sample and only trace iodide and bromide were detected in livers and kidneys of both Control and Asp-Oil steers at levels safe for human consumption. Steers demonstrated normal rumen development typical of feedlot diets. This study confirms that Asp-Oil safely induces significant productivity benefits and CH4 reductions in feedlot beef production. Commercial adoption of Asparagopsis can benefit feedlot beef production and reduces the climate change contribution of livestock production.展开更多
Ethoxyquin(EQ)is a widely used feed additives for aquaculture,but the potential hazard to fish and consumers are not fully understood.In this work,EQ was applied to tilapia fed with either high-fat or low-fat feed,and...Ethoxyquin(EQ)is a widely used feed additives for aquaculture,but the potential hazard to fish and consumers are not fully understood.In this work,EQ was applied to tilapia fed with either high-fat or low-fat feed,and the changes in growth performance and intestinal barrier integrality of genetically improved farmed tilapia was observed.Additionally,the microbiota in the intestinal content and flesh was analyzed by 16S rDNA sequencing,and the flesh metabolites was measured by LC-MS/MS untargeted metabolomics.In the low-fat group,EQ increased weight gain and feed conversion rate,but reduced survival rate.In the high-fat group,only weight gain decreased,and there was no significant effect on feed conversion rate and survival rate.Additionally,the intestinal villi and microbiota diversity was impaired in both feeding conditions.Microbiota analysis revealed that EQ resulted in different composition and lower diversity of the flesh microbiota and upregulated the proportion of potential pathogens.EQ also changed the flesh metabolome,decreasing beneficial metabolites and increasing potential harmful components.This work elucidated the effect of EQ on growth performance of tilapia and implied that it has adverse effects on tilapia and may be passed on to consumers.展开更多
The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant res...The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant response in cats. The animals were divided into two groups of seven animals each. One group received DNF, and the other consumed commercial extruded dry feed (DCF). The experiment lasted 45 days and we measured daily consumption and collected blood and feces samples. The animals in the DNF group showed greater digestibility of fiber and mineral matter than DCF. Cats in the DNF group had a higher volume of feces. DNF cats had lower leukocyte and granulocyte counts and cholesterol levels. Serum enzymatic antioxidant responses and non-enzymatic were higher in DNF cats. Cats in the DNF group showed lower serum acute phase proteins in addition to a tendency toward a higher concentration of transferrin than in the DCF group. Fecal Escherichia coli and total coliform counts of cats fed DNF were higher than DCF. We conclude that the daily consumption of cats is adequate. This feed had greater digestibility of fiber and mineral matter, in addition to an improvement in antioxidant and immunological responses.展开更多
Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between ...Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour.展开更多
Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the herd.However,the provis...Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the herd.However,the provision of dietary excess of AA,such as Lys,may lead to reduced appetite and growth in pigs.The mechanisms modulat-ing these responses have not been extensively investigated.This study evaluated the effect of Lys dietary excesses on performance and satiety biomarkers in post weaning pigs.Methods Twenty-four pigs aged 21 d and weighing 6.81±0.12kg(mean±SEM)were individually housed and offered 1 of 4 dietary treatments for 3weeks:a diet containing a standardized ileal digestible Lys reaching 100%(T0),120%(T1),150%(T2)or 200%(T3)of the NRC(2012)requirements.At the end of the experiment,blood samples from the cephalic vein of the T0 and T3 groups were obtained for AA analysis.In addition,primary intestinal cultures from T0 pigs were used,following their humane killing,to evaluate the effect of Lys on gut hormone secretion and AA sensors gene expression under ex vivo conditions.Results Feed intake was linearly reduced(P<0.001)and the weight gain to feed ratio reduced(P<0.10)with increased dietary levels of Lys during the third-and first-week post weaning,respectively.Cholecystokinin con-centration(P<0.05)and the metabotropic glutamate receptor 1 and the solute carrier family 7 member 2(P<0.10)gene expression was enhanced in proximal jejunum tissues incubated with Lys at 20mmol/L when compared to the control(Lys 0mmol/L).Plasma Lys and Glu(P<0.05)concentration increased in the T3 compared to T0 pigs.In contrast,plasma levels of His,Val,Thr,Leu(P<0.05)and Gln(P<0.10)were lower in T3 than T0 pigs.Conclusion The present results confirm that excess dietary Lys inhibits hunger in pigs.Moreover,the results provide evidence of pre-and post-absorptive mechanisms modulating these responses.Lys dietary excesses should be nar-rowed,when possible,to avoid negative effects of the AA on appetite in pigs.展开更多
基金the Sichuan Science and Technology Program(Nos.23ZHCG0049,2023YFG0078,23ZHCG0030,2021ZDZX0007)SCU-SUINING Project(2022CDSN-14).
文摘To solve the problem of long response time when users obtain suitable cutting parameters through the Internet based platform,a case-based reasoning framework is proposed.Specifically,a Hamming distance and Euclidean distance combined method is designed to measure the similarity of case features which have both numeric and category properties.In addition,AHP(Analytic Hierarchy Process)and entropy weight method are integrated to provide features weight,where both user preferences and comprehensive impact of the index have been concerned.Grey relation analysis is used to obtain the similarity of a new problem and alternative cases.Finally,a platform is also developed on Visual Studio 2015,and a case study is demonstrated to verify the practicality and efficiency of the proposed method.This method can obtain cutting parameters which is suitable without iterative calculation.Compared with the traditional PSO(Particle swarm optimization algorithm)and GA(Genetic algorithm),it can obtain faster response speed.This method can provide ideas for selecting processing parameters in industrial production.While guaranteeing the characteristic information is similar,this approach can select processing parameters which is the most appropriate for the production process and a lot of time can be saved.
基金the National Science and Technology Major Project(Grant No.2017-VII-0011-0106)Natural Science Foundation of Heilongjiang Province(Grant No.ZD2019A001).
文摘Experimental investigations on dynamic in-plane compressive behavior of a plain weave composite were performed using the split Hopkinson pressure bar. A quantitative criterion for calculating the constant strain rate of composites was established. Then the upper limit of strain rate, restricted by stress equilibrium and constant loading rate, was rationally estimated and confirmed by tests. Within the achievable range of 0.001/s-895/s, it was found that the strength increased first and subsequently decreased as the strain rate increased. This feature was also reflected by the turning point(579/s) of the bilinear model for strength prediction. The transition in failure mechanism, from local opening damage to completely splitting destruction, was mainly responsible for such strain rate effects. And three major failure modes were summarized under microscopic observations: fiber fracture, inter-fiber fracture, and interface delamination. Finally, by introducing a nonlinear damage variable, a simplified ZWT model was developed to characterize the dynamic mechanical response. Excellent agreement was shown between the experimental and simulated results.
文摘In a study published in Nature Catalysis on May 28,Chinese scientists unveiled a nove l approach to transforming lignin,a major component of woody biomass,into valuable chemical products(doi:10.1038/s41929-024-01165-w).This discovery could pave the way for more sustainable and efficient use of renewable resources.
基金supported in part by the National Science Fund for Excellent Young Scholars of China (62222317)the National Natural Science Foundation of China (61973319)+4 种基金the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China (61860206014)111 Project of China (B17048)Science and Technology Innovation Program of Hunan Province (2022WZ1001)the Natural Science Foundation of Changsha (kq2208287)the Postdoctoral Fund of Central South University (22022136)。
文摘This article proposes an integral-based event-triggered attack-resilient control method for the aircraft-on-ground(AoG) synergistic turning system with uncertain tire cornering stiffness under stochastic deception attacks. First, a novel AoG synergistic turning model is established with synergistic reverse steering of the front and main wheels to decrease the steering angle of the AoG fuselage, thus reducing the steady-state error when it follows a path with some large curvature. Considering that the tire cornering stiffness of the front and main wheels vary during steering, a dynamical observer is designed to adaptively identify them and estimate the system state at the same time.Then, an integral-based event-triggered mechanism(I-ETM) is synthesized to reduce the transmission frequency at the observerto-controller end, where stochastic deception attacks may occur at any time with a stochastic probability. Moreover, an attackresilient controller is designed to guarantee that the closed-loop system is robust L2-stable under stochastic attacks and external disturbances. A co-design method is provided to get feasible solutions for the observer, controller, and I-ETM simultaneously. An optimization program is further presented to make a tradeoff between the robustness of the control scheme and the saving of communication resources. Finally, the low-and high-probability stochastic deception attacks are considered in the simulations. The results have illustrated that the AoG synergistic turning system with the proposed control method follows a path with some large curvature well under stochastic deception attacks. Furthermore,compared with the static event-triggered mechanisms, the proposed I-ETM has demonstrated its superiority in saving communication resources.
基金supported by the Outstanding Action Plan of Chinese Sci-tech Journals(Grant No.OAP–C–077)。
文摘The interaction between light and temperature is known to influence the seasonal growth of trees.Traditional studies on"light"primarily focus on day length,specifically short day(SD)or long day(LD)conditions.However,little research has been conducted on the process of transitioning between SD and LD conditions.
基金supported by research grants from Regionalt Forskningsfond (RFF) Trondelag (In FeedProject number: 309859),where Nord University is the project leading institution,and Gullimunn AS and Mære Landbruksskole are project partnerssupported by the CEER project (Project number: 2021/10345) funded by the Norwegian Agency for International Cooperation and Quality Enhancement in Higher Education (HK-dir) under the Norwegian Partnership Program for Global Academic Cooperation (NORPART ) with support from the Norwegian Ministry of Education and Research (MER)。
文摘Yellow mealworm larvae(YML;Tenebrio molitor) are considered as a valuable insect species for animal feed due to their high nutritional values and ability to grow under different substrates and rearing conditions. Advances in the understanding of entomophagy and animal nutrition over the past decades have propelled research areas toward testing multiple aspects of YML to exploit them better as animal feed sources. This review aims to summarize various approaches that could be exploited to maximize the nutritional values of YML as an animal feed ingredient. In addition, YML has the potential to be used as an antimicrobial or bioactive agent to improve animal health and immune function in production animals. The dynamics of the nutritional profile of YML can be influenced by multiple factors and should be taken into account when attempting to optimize the nutrient contents of YML as an animal feed ingredient. Specifically, the use of novel land-based and aquatic feeding resources, probiotics, and the exploitation of larval gut microbiomes as novel strategies can assist to maximize the nutritional potential of YML. Selection of relevant feed supplies, optimization of ambient conditions, the introduction of novel genetic selection procedures, and implementation of effective post-harvest processing may be required in the future to commercialize mealworm production. Furthermore, the use of appropriate agricultural practices and technological improvements within the mealworm production sector should be aimed at achieving both economic and environmental sustainability. The issues highlighted in this review could pave the way for future approaches to improve the nutritional value of YML.
基金supported by the the National Natural Science Foundation of Fujian Province of China (2020J01697,2020J01699).
文摘The multi-pass turning operation is one of the most commonly used machining methods in manufacturing field.The main objective of this operation is to minimize the unit production cost.This paper proposes a Gaussian quantum-behaved bat algorithm(GQBA)to solve the problem of multi-pass turning operation.The proposed algorithm mainly includes the following two improvements.The first improvement is to incorporate the current optimal positions of quantum bats and the global best position into the stochastic attractor to facilitate population diversification.The second improvement is to use a Gaussian distribution instead of the uniform distribution to update the positions of the quantum-behaved bats,thus performing a more accurate search and avoiding premature convergence.The performance of the presented GQBA is demonstrated through numerical benchmark functions and amulti-pass turning operation problem.Thirteen classical benchmark functions are utilized in the comparison experiments,and the experimental results for accuracy and convergence speed demonstrate that,in most cases,the GQBA can provide a better search capability than other algorithms.Furthermore,GQBA is applied to an optimization problem formulti-pass turning,which is designed tominimize the production cost while considering many practical machining constraints in the machining process.The experimental results indicate that the GQBA outperforms other comparison algorithms in terms of cost reduction,which proves the effectiveness of the GQBA.
基金supported by the National Natural Science Foundation of China(Grant No.52175431)the Natural Science Foundation of Tianjin of China(Grant No.22JCZDJC00730)the Scientific Research Project of Tianjin Municipal Education Commission(Grant No.2022ZD021).
文摘With the increasing use of difficult-to-machine materials in aerospace applications,machining requirements are becoming ever more rigorous.However,traditional single-point diamond turning(SPDT)can cause surface damage and tool wear.Thus,it is difficult for SPDT to meet the processing requirements,and it has significant limitations.Research indicates that supplementing SPDT with unconventional techniques can,importantly,solve problems due to the high cutting forces and poor surface quality for difficult-to-machine materials.This paper first introduces SPDT and reviews research into unconventional techniques for use with SPDT.The machining mechanism is discussed,and the main advantages and disadvantages of various methods are investigated.Second,hybrid SPDT is briefly described,which encompasses ultrasonic-vibration magnetic-field SPDT,ultrasonic-vibration laser SPDT,and ultrasonic-vibration cold-plasma SPDT.Compared with the traditional SPDT method,hybrid SPDT produces a better optical surface quality.The current status of research into unconventional techniques to supplement SPDT is then summarized.Finally,future development trends and the application prospects of unconventional assisted SPDT are discussed.
文摘This paper presents vehicle localization and tracking methodology to utilize two-channel LiDAR data for turning movement counts. The proposed methodology uniquely integrates a K-means clustering technique, an inverse sensor model, and a Kalman filter to obtain the final trajectories of an individual vehicle. The objective of applying K-means clustering is to robustly differentiate LiDAR data generated by pedestrians and multiple vehicles to identify their presence in the LiDAR’s field of view (FOV). To localize the detected vehicle, an inverse sensor model was used to calculate the accurate location of the vehicles in the LiDAR’s FOV with a known LiDAR position. A constant velocity model based Kalman filter is defined to utilize the localized vehicle information to construct its trajectory by combining LiDAR data from the consecutive scanning cycles. To test the accuracy of the proposed methodology, the turning movement data was collected from busy intersections located in Newark, NJ. The results show that the proposed method can effectively develop the trajectories of the turning vehicles at the intersections and has an average accuracy of 83.8%. Obtained R-squared value for localizing the vehicles ranges from 0.87 to 0.89. To measure the accuracy of the proposed method, it is compared with previously developed methods that focused on the application of multiple-channel LiDARs. The comparison shows that the proposed methodology utilizes two-channel LiDAR data effectively which has a low resolution of data cluster and can achieve acceptable accuracy compared to multiple-channel LiDARs and therefore can be used as a cost-effective measure for large-scale data collection of smart cities.
基金Project supported by the Natural Science Foundation of China (Grant Nos.62075107,61935006,62090064,and62090065)K.C.Wong Magna Fund in Ningbo University。
文摘A novel method for designing chalcogenide long-period fiber grating(LPFG) sensors based on the dual-peak resonance effect of the LPFG near the phase matching turning point(PMTP) is presented. Refractive index sensing in a high-refractive-index chalcogenide fiber is achieved with a coated thinly clad film. The dual-peak resonant characteristics near the PMTP and the refractive index sensing properties of the LPFG are analyzed first by the phase-matching condition of the LPFG. The effects of film parameters and cladding radius on the sensitivity of refractive index sensing are further discussed. The sensor is optimized by selecting the appropriate film parameters and cladding radius. Simulation results show that the ambient refractive index sensitivity of a dual-peak coated thinly clad chalcogenide LPFG at the PMTP can be 2400 nm/RIU, which is significantly higher than that of non-optimized gratings. It has great application potential in the field of chemical sensing and biosensors.
文摘This paper presents the results of experimental work carried out in dry turning of cast duplex stainless steels (ASTM A 995 Grade4A and ASTM A 995 Grade5A) using TiC and TiCN coated cemented carbide cutting tools. The turning tests were conducted at five different cutting speeds (80, 100, 120, 140 and 160 m/min) and three different feed rates (0.04, 0.08 and 0.12 mm/rev) with a constant depth of cut (0.5 mm). The influence of cutting speed and feed rate on the machined surface roughness was investigated. Texture analysis (Bulk) was also carried out to study the impact of preferred orientation on the resulting surface roughness. The result reveals that the increasing cutting speed decreases the surface roughness till a particular point and then increases whereas;the surface roughness value decreases with the decreasing feed rate. Presence of alpha fiber (Bulk texture analysis) in the austenite phase of 4A work piece material leads to better surface finish. Among both the grades, surface finish of grade 4A is better than grade 5A work piece material.
文摘The U.S.dollar has long stood tall as the pre-eminent global currency for international cross-border trade settlements and foreign exchange reserves ever since the launch of the Bretton Woods institutions-International Monetary Fund(IMF)and World Bank(WB).
文摘Single-point diamond turning (SPDT) is widely used in the machining of infrared materials and metal-based mirrors. Diamond tips can scratch material, replicate the shape of the tip, and create annular turning marks on optical surfaces, which can have unpredictable adverse effects on imaging. In order to predict the effect of turning marks diffraction on the degradation of imaging quality, a model of the influence of SPDT processing parameters on the reduction of system imaging MTF under the influence of ideal grating turning marks diffraction was established. The results show that the depth of the turning mark will lead to the decline of MTF, especially the low frequency information. Finally, a method is proposed to reduce the effect of turning marks diffraction through changing the processing parameters. .
文摘Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to 6 months of age to EBF until about 6 months of age, with the addition of complementary foods thereafter. This recommendation confirms that breast milk alone is sufficient to meet infants’ nutritional requirements for the first 6 months of life. The main objective of this study was to investigate the effect of various feeding practices on the Nutritional status of infants 0 - 12-month-old in the Kumba 1 Sub-Division. A descriptive cross-sectional study was conducted from December 2019 to August 2020. A total of 341 nursing mothers and their infants 0 - 12 months of age were recruited. Socio-demographic factors and the different feeding habits of the children were assessed using a semi-structured questionnaire. Nutritional status was assessed using anthropometric measurements. The overall proportion of infants who exclusively breastfed for 6 months was 69.2% and those who were mix-fed were 30.8% in the study area. The overall prevalence of malnutrition in the population was 61.0%. Among the malnourished children, 53.1% were underweight, 19.6% were wasted and 10.0% were stunted. Though not significant, the prevalence of wasting (21.0%) and underweight (58.3%) was higher among Mix-Fed (MF) children when compared to their EBF counterparts. Feeding practices affected the nutritional status of the infants. Underweight and wasting were observed among infants on Complementary Feeding (CF), although some exclusively breast-fed infants were stunted. Hence, nursing mothers should try as much as possible to practice EBF as recommended by WHO and can practice CF when the child is above six months.
文摘Research using open-circuit respiration chambers has established that Asparagopsis bioactive compounds stabilized in canola oil (Asp-Oil), delivering a range of inclusion between 34 - 51 mg bromoform (CHBr3)/kg dry matter intake (DMI), inhibits methane (CH4) emissions > 98% in feedlot cattle. In this study, Asp-Oil was fed at 35 mg CHBr3/kg DMI in the feedlot finisher diet under highly replicated and commercially relevant conditions, and adequately powered to confirm differences as low as 3.3% in feed conversion efficiency (FCE). The study also evaluated the effect of Asp-Oil on CH4 production (g/day), carcass and meat-eating qualities, animal health, and food safety. The experiment consisted of 300 Angus-Shorthorn (Bos taurus) steers in 30 pens of 10 and fed a barley-based ration supplemented with canola oil (Control, n = 15), or Asp-Oil (n = 15) for total 81-d, inclusive of 21-d transition to full Asp-Oil and grain inclusion in the finisher ration. Reduction of CH4 was measured using GreenFeed Emissions Monitors (GEM) in a subset of 2 pens in both Control and Asp-Oil. However, 67% of CH4 measurements were recorded below the GEM’s limit of detection. An inhibition range of 58% - 98% was demonstrated by collectively using GEM and preliminary respiration chamber measurements. Asp-Oil improved FCE 7.4% in the finisher diet, and 5.6% across transition and finisher periods. During the transition steps the steers had not yet received their full allocations of grain and Asp-Oil which is responsible for the lower FCE benefits. A 4.1% lower DMI in the finisher period contributed to benefits in FCE with no effect on daily weight gains. Cost of feed and weight gain were reduced $0.35/head/day and $0.23/kg, respectively, in steers receiving Asp-Oil. Residues of Asparagopsis CHBr3 were not detected in any sample and only trace iodide and bromide were detected in livers and kidneys of both Control and Asp-Oil steers at levels safe for human consumption. Steers demonstrated normal rumen development typical of feedlot diets. This study confirms that Asp-Oil safely induces significant productivity benefits and CH4 reductions in feedlot beef production. Commercial adoption of Asparagopsis can benefit feedlot beef production and reduces the climate change contribution of livestock production.
基金supported by the National Natural Science Foundation of China(32061133004)the Major Project of Digital Plus Discipline Construction of Zhejiang Gongshang University(SZJ2022A010)the Zhejiang Provincial Natural Science Foundation of China(LGN21C200013).
文摘Ethoxyquin(EQ)is a widely used feed additives for aquaculture,but the potential hazard to fish and consumers are not fully understood.In this work,EQ was applied to tilapia fed with either high-fat or low-fat feed,and the changes in growth performance and intestinal barrier integrality of genetically improved farmed tilapia was observed.Additionally,the microbiota in the intestinal content and flesh was analyzed by 16S rDNA sequencing,and the flesh metabolites was measured by LC-MS/MS untargeted metabolomics.In the low-fat group,EQ increased weight gain and feed conversion rate,but reduced survival rate.In the high-fat group,only weight gain decreased,and there was no significant effect on feed conversion rate and survival rate.Additionally,the intestinal villi and microbiota diversity was impaired in both feeding conditions.Microbiota analysis revealed that EQ resulted in different composition and lower diversity of the flesh microbiota and upregulated the proportion of potential pathogens.EQ also changed the flesh metabolome,decreasing beneficial metabolites and increasing potential harmful components.This work elucidated the effect of EQ on growth performance of tilapia and implied that it has adverse effects on tilapia and may be passed on to consumers.
文摘The present study aimed to determine whether natural dehydrated feed (DNF) can replace dry extruded feed while preserving the required daily intake, nutrient digestibility and benefits for immunity and antioxidant response in cats. The animals were divided into two groups of seven animals each. One group received DNF, and the other consumed commercial extruded dry feed (DCF). The experiment lasted 45 days and we measured daily consumption and collected blood and feces samples. The animals in the DNF group showed greater digestibility of fiber and mineral matter than DCF. Cats in the DNF group had a higher volume of feces. DNF cats had lower leukocyte and granulocyte counts and cholesterol levels. Serum enzymatic antioxidant responses and non-enzymatic were higher in DNF cats. Cats in the DNF group showed lower serum acute phase proteins in addition to a tendency toward a higher concentration of transferrin than in the DCF group. Fecal Escherichia coli and total coliform counts of cats fed DNF were higher than DCF. We conclude that the daily consumption of cats is adequate. This feed had greater digestibility of fiber and mineral matter, in addition to an improvement in antioxidant and immunological responses.
文摘Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour.
基金This study was partially supported by The University of Queensland and Australian Pork Limited as part of the project APL 2016/053.
文摘Background Commercial diets are frequently formulated to meet or exceed nutrient levels including those of lim-iting essential amino acids(AA)covering potential individual variations within the herd.However,the provision of dietary excess of AA,such as Lys,may lead to reduced appetite and growth in pigs.The mechanisms modulat-ing these responses have not been extensively investigated.This study evaluated the effect of Lys dietary excesses on performance and satiety biomarkers in post weaning pigs.Methods Twenty-four pigs aged 21 d and weighing 6.81±0.12kg(mean±SEM)were individually housed and offered 1 of 4 dietary treatments for 3weeks:a diet containing a standardized ileal digestible Lys reaching 100%(T0),120%(T1),150%(T2)or 200%(T3)of the NRC(2012)requirements.At the end of the experiment,blood samples from the cephalic vein of the T0 and T3 groups were obtained for AA analysis.In addition,primary intestinal cultures from T0 pigs were used,following their humane killing,to evaluate the effect of Lys on gut hormone secretion and AA sensors gene expression under ex vivo conditions.Results Feed intake was linearly reduced(P<0.001)and the weight gain to feed ratio reduced(P<0.10)with increased dietary levels of Lys during the third-and first-week post weaning,respectively.Cholecystokinin con-centration(P<0.05)and the metabotropic glutamate receptor 1 and the solute carrier family 7 member 2(P<0.10)gene expression was enhanced in proximal jejunum tissues incubated with Lys at 20mmol/L when compared to the control(Lys 0mmol/L).Plasma Lys and Glu(P<0.05)concentration increased in the T3 compared to T0 pigs.In contrast,plasma levels of His,Val,Thr,Leu(P<0.05)and Gln(P<0.10)were lower in T3 than T0 pigs.Conclusion The present results confirm that excess dietary Lys inhibits hunger in pigs.Moreover,the results provide evidence of pre-and post-absorptive mechanisms modulating these responses.Lys dietary excesses should be nar-rowed,when possible,to avoid negative effects of the AA on appetite in pigs.