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Real-time, accurate, and robust localisation is critical for autonomous vehicles (AVs) to achieve safe, efficient driving, whilst real-time performance is essential for AVs to achieve their current position in time for decision making. To date, no review paper has quantitatively compared the real-time performance between different localisation techniques based on various hardware platforms and programming languages and analysed the relations among localisation methodologies, real-time performance and accuracy. Therefore, this paper discusses state-of-the-art localisation techniques and analyses their localisation performance in AV application. For further analysis, this paper firstly proposes a localisation algorithm operations capability (LAOC)-based equivalent comparison method to compare the relative computational complexity of different localisation techniques; then, it comprehensively discusses the relations among methodologies, computational complexity, and accuracy. Analysis results show that the computational complexity of localisation approaches differs by a maximum of about 〖10〗^7 times, whilst accuracy varies by about 100 times. Vision- and multi-sensor fusion-based localisation techniques have about 2–5 times potential for improving accuracy compared with lidar-based localisation. Lidar- and vision-based localisation can reduce computational complexity by improving image registration method efficiency. Multi-sensor fusionbased localisation can achieve better real-time performance compared with lidar- and vision-based localisation because each standalone sensor does not need to develop a complex algorithm to achieve its best localisation potential. Vehicle-to-everything (V2X) technology can improve positioning robustness. Finally, results show that the fusion technique combined with V2X has considerable potential for achieving a cost-efficient localisation solution for AVs.

Context Heat stress has led to a serious reduction in dairy cows production performance, thus increasing the stress of feeding and reproduction management. Aims Heat stress arises when cows are unable to dissipate excess body heat, we aimed to investigate the effects of ambient temperature (AT) and humidity on diurnal body temperature and activity. Methods For improving the technology for rearing dairy cows, the vaginal temperature (VT) and activity of 60 Holstein heifers in summer (n = 20), autumn (n = 20), and winter (n = 20) were measured using the oestrus monitoring system. Key results We found that VT fluctuated slightly (~38.22–38.32°C) when AT and temperature-humidity index (THI) were lower than 20°C and 68, respectively. However, when this threshold is reached, VT increased significantly with increasing AT and THI, whereas activity decreased significantly. Conclusions Heat stress may be caused when THI is above 68 and cow’s VT reaches 38.32°C. Evidently, when the THI exceeds 68 and VT is more than 38.32°C, suitable measures for reducing the effect of heat stress on the productivity of dairy cows should be taken. Implications The combined monitoring of VT and THI might provide accurate guidance for preventing and controlling heat stress.

As a large number of mobile terminals are connected to the IoT, the security problem of IoT is a challenge to the IoT technology. Blockchain technology has the characteristics of decentralization, data encryption, smart contract, and so on, especially suitable in the complex heterogeneous network. However, sequential access based on block files in the blockchain hinders efficient query processing. The problem is due to current blockchain solutions do not support temporal data processing. In this paper, we propose two index building methods (TISD and TIF) to address this issue in Hyperledger Fabric System. TISD (temporal index based on state databases) segments the historical data by time interval in the time dimension and indexes events at the same time interval. TIF (temporal index based on files) builds the index of files by the block transaction data, which is arranged in chronological order and is stored at a certain time interval. In the experimental part, we compare the query time on two datasets and analyse the query performance. Experiments demonstrated that our two methods are relatively stable in overall time performance on different datasets in the Hyperledger Fabric System.

PurposeThis study aims to explore the combined strategies leading to successful repair of two types of trust in Chinese construction projects and provide an effective guidance and control trust repair in construction projects. During the research period, the author interviewed 150 managers from 50 Chinese construction projects and collected details of 125 violations. The research examines the effect of combined strategy of trust repair in Chinese management scenario.Design/methodology/approachThis study adopted a mixed, quantitative, qualitative and exploratory approach. The author first extracted six strategies, namely, apology, denial, penance, communication, promise and compensation, from the literature review and generalization. Then, the author conducted an interview with 150 managers from 50 China construction projects. And the author analyzed the data through qualitative comparative analysis (QCA).FindingsWhen competence-based trust is broken, violators should adopt communication and promise, demonstrate their competence and qualification, and change the attributions of competence from the trustor. When integrity-based trust is broken, violators should apologize, actively admit the mistake, show a positive attitude and seek the forgiveness from the trustor. After reconstructing trustors' perceptions of competence or integrity, violators should also make a promise to trustors for the future. The result of this research not only illustrates the sufficiency and necessity of a single strategy for trust repair but also explores the combination of trust repair strategies that rebuild the trust.Research limitations/implicationsThis study is limited to 50 construction projects in the Chinese construction context, so conclusions are limited in application. Data used in this research did not provide an in-depth analysis of trust repair failures. Thus, additional research is needed to explore why trust was not repaired. The study is also limited to examining the Chinese construction project organizations only, and future studies should incorporate organizations in other nations and regions.Practical implicationsCompared with using a single strategy, a combined strategy provides a contribution to the future practice of repair broken relationship between construction project organizations. This research helps to organize decisions and benefits managers, from Chinese owners and contractors, in choosing which of these strategies repair trust. The author also provides a specific combination of strategies to repair relationships for international companies that have conflicts with Chinese construction companies.Originality/valueThis research is among the early studies in China that preliminary examines the combined strategy of trust repair between Chinese owners and contractors by using causal attribution theory and QCA. This study makes a valuable contribution toward combined strategy in construction project and the knowledge system of trust repair. Future studies could build on the findings from the current study to develop a cross-cultural research on trust repair.

The seasonal and interannual variabilities of sea surface wind (SSW) in the South China Sea (SCS), especially in coral reef regions such as Nansha Islands, Xisha Islands, Zhongsha Islands and Dongsha Islands were investigated in detail using the Blended Sea Winds dataset (1988–2017). Annual and monthly variations of SSW and sea surface temperature (SST) in the four zones were investigated. Empirical Orthogonal Function (EOF) analysis of wind field was performed to aid in better understanding the different spatial patterns. The results indicate that, as observed in the spatial distribution of the first mode of monthly mean wind speed anomaly, the magnitudes in the four island zones are all negative and are similar to each other, showing that the variations of SSW in the four island zones are consistent. In the second mode, the magnitudes in Nansha Islands are opposite to those in the other three zones. The spatial distribution of the third mode reflects regional differences. The maximum annual SSW appears in Dongsha Islands, and the minimum appears in Nansha Islands. The interannual variations of SSW in all island zones are basically concurrent. The island zones with high SSW mostly have low SST, and vice versa. There may be an inverse relationship between SSW and SST in coral reef regions in the SCS. The multi-year monthly variations of SSW in the island zones present a ‘W’-shaped structural variation. Each island undergoes two months of minimum SSW every year, one during March–May (MAM) and the other during September–November (SON). Both months are in monsoon transition periods. During the months with low SSW, high SST appears. The SST peaks almost correspond to the SSW troughs. This further indicates that SSW and SST may have opposite changes in coral reef regions. Coral bleaching events often correspond to years of high SST and low SSW.

PurposeThe purpose of this study is to examine the factors influencing the transaction costs (TCs) in megaprojects to provide a basis for controlling project costs.Design/methodology/approachThis study selects six factors influencing the TCs in megaprojects from the perspective of TC theory and relational contract theory (RCT) through literature review. On the basis of crisp-set qualitative comparative analysis (QCA), this study tests combined factors influencing the TCs and the interaction between them.FindingsResults show that in megaprojects, TCs are affected by combination factors. The combination of asset specificity, uncertainty, transaction frequency and trust and the combination of asset specificity, reputation and trust will control TCs in certain situations. In the configuration leading to high project TCs, the combination of environmental and behavioral uncertainties is a necessary condition.Originality/valueThis paper fills up the research gap in the field of megaproject TCs, and researchers can focus on this field in the future.

The aim of this study was to investigate the role of the insulin-like growth factor-1 receptor (IGF-1R)Rats were divided into four groups. The sham group received sham operation and a single intraperitoneal administration of vehicle. The ovariectomy (OVX) group was subjected to bilateral OVX and vehicle injection. The streptozotocin (STZ) group received sham operation and a single STZ injection to induce hyperglycemia. The OVX + STZ group received bilateral OVX and a single STZ injection. Dual-energy X-ray absorptiometry measurement, bone biomechanics test, micro-computed tomography scan, and hematoxylin-eosin staining were performed to evaluate bone alteration in this model. The expression of relevant signals including IGF-1R, glycogen synthase kinase-3β (GSK-3β), and β-catenin were examined by quantitative real-time polymerase chain reaction and western blot.The OVX, STZ, and OVX + STZ groups induced bone loss, attenuated bone strength, and impaired microarchitecture compared with the sham group, respectively. Compared with OVX, more serious bone damage was found in the OVX + STZ group, which showed enhanced phosphorylation of IGF-1R, GSK-3β, and β-catenin.OVX plus STZ induced more serious bone impairment than OVX alone, which involves the IGF-1R/β-catenin signaling axis in the pathogenesis. This may provide a potential target for treatment of postmenopausal diabetic osteoporosis.

Estrus identification is important in dairy cow production. At present, estrus identification is automated with a pedometer or accelerometer and the results remain unsatisfactory. It was previously reported that body temperature changes during estrus. In the present study, dairy cow vaginal temperature (VT) was monitored during various seasons, and an increase in VT of 0.3 °C was suggested for the onset of estrus, using an automated VT monitoring system developed in-house. Natural and synchronized estrus were measured simultaneously. The VT was determined to be in circadian rhythm and significantly higher in summer than in either autumn or winter (P

With the development of standardization and scaling in the dairy farming industry, timely and accurate pregnancy diagnosis is required to improve the benefits of breeding by shortening the calving interval. However, the current pregnancy diagnostic methods cannot meet the requirements of the industry. Here, we review changes in the physiological indexes and in the function and morphological status of the reproductive organs of dairy cows at the early stages of pregnancy. In addition, the corresponding pregnancy diagnostic methods based on certain indexes are well development, and the pregnancy diagnostic approaches based on remote sensing and automation technology have become inevitable trends in the industry. These applications will reveal physiological regularities in pregnancy and benefit the detailed management of dairy cows during early pregnancy.

Camera-based vessel identification is one of the essential maritime surveillance measures. The existing deep learning (DL)-based vessel classification methods have challenges in achieving the detailed vessel information (e.g., vessel identity) under poor visual conditions. In some applications, they cannot meet the safe scheduling and abnormal activity identification purposes in the camera surveillance system. This paper proposed a fusion framework, which takes the visual detection and the automatic identification system (AIS) as inputs to obtain accurate and robust vessel identification to address these challenges. Visual detection uses an innovative method to estimate the distance of the identified vessel target from the camera and the azimuth angle relative to the camera based on the images from the monocular camera. The distance and azimuth angle were further fused with AIS data to obtain the fused output. The test results based on 3976 images show that the mean absolute error of the visual-based distance estimation method is 0.72km. The success rate of visual detection and AIS data association is 75.7%.

With the continuous improvement of the performance of the IoT and mobile devices, the IoT technology brings convenience to people’s lives but leaks out personal privacy at the same time. Federated learning is a kind of machine learning technology that can protect data privacy. Different from current machine learning methods, Federated learning is usually facing non-Identically Independently Distributions (no-IID) data and keeps data in local places. Therefore, the effectiveness of existing machine learning methods in federated learning non-IID issues decreases greatly. At the same time, federated learning needs to interact with multiple edge learning nodes. With the increasing number of edge nodes, the cost of communication becomes higher and higher, and the parameter weight calculation of more independent nodes is also a problem. In this paper, we propose to balance the federated learning model by using Earth Mover’s Distance to calculate the weights of different node parameters. Our method can reduce the impact of data non-independent identically distributed problems on the model so that the federated learning model will not be biased to the distributed nodes in the data set. Besides, this paper also proposes a method to compress redundant communication between nodes and servers in the process of training. Experimental results show that this paper method improves the accuracy by about 4% compared with the traditional federal learning average algorithm, and the gradient communication is compressed to about 6% of the original communication times.

Heat stress (HS) is one of the main environmental factors affecting the efficiency of poultry production. The yellow-feather chickens (YFC) as an indigenous strain of chicken is a popular poultry breed in China. Our previous study used the RNA-seq to analyze the gene expression profiles of male YFC under HS and showed that the lipid and energy metabolism pathways are activated in livers of YFC exposed to acute HS (38°C, 4 h and 25°C recovery 2 h). In this study, we used quantitative proteome analysis based on iTRAQ to study the liver response of YFC to cycle chronic HS (38 ± 1°C, 8 h/d, 7 d, CyCHS). The male YFCs treatment used the CyCHS from 22 to 28 days of age. The liver tissue samples were collected at 28 d old. A total of 39,327 unique peptides matches were detected using iTRAQ analysis and 4,571 proteins exhibited a false discovery rate of 1% or less. Forty-six significant differentially expressed proteins (DEPs) were detected in the CyCHS group compared with the control group for the liver samples, including up- and down-regulated DEPs were 18 and 28, respectively. We found that the enriched biological process terms of the DEPs expressed in the liver were related to DNA metabolic process, oxidation-reduction process, oxidative stress and gluconeogenesis. In KEGG pathway analysis. Most of the hepatic DEPs were annotated to glutathione metabolism and TCA cycle in response to CyCHS. The up-regulation of 5 DEPs (GPX1, GSTT1, GSTT1L, RRM2, and LOC100859645) in the glutathione metabolism pathway likely reflects an attempt to deal with oxidative damage by CyCHS. The down-regulation of 3 DEPs (Isocitrate dehydrogenase [IDH3A], IDH3B, and phosphoenolpyruvate carboxykinase 1) in the TCA cycle pathway contributes to the regulation mechanism of energy metabolism and probably to cope with the balance of heat production and dissipation during CyCHS in order to adapt to high temperature environments. Our results provide insights into the potential molecular mechanism in heat-induced oxidative stress and energy in YFCs and future studies will investigate the functional genes associated with the response to HS.

The behavior preference and decision matching of participants have an important influence on the governance of megaproject uncertainty. However, the framework and drivers largely are unknow...

Background: Mastitis is a common disease in cows breeding. The milk quality will be significantly reduced with increased milk somatic cells which often occur in cows with mastitis. In the current study, we reported that melatonin significantly reduced the milk somatic cell count in Holstein cow with mastitis. In addition, the nutritional value of the milk also significantly improved by melatonin treatment. Results: The results showed that melatonin significantly suppressed the milk somatic cell score under any of the tested conditions. A long term of melatonin application (one year) to the cows with mastitis suppressed the somatic cell score by roughly 63% which was more efficiency than that of some antibiotic treatments. Melatonin treatment also improved the milk nutritional value by reducing its fat but increasing its lactose and protein contents. Conclusions: Melatonin application significantly improved DHI. The beneficial effects of melatonin on DHI are likely attributed to the antioxidant and anti-inflammatory activities of melatonin.

Background: Understanding the interactions among soil microbial species and how they responded to disturbances are essential to ecological restoration and resilience in the semi-humid and semi-arid damaged mining areas. This information, however, remains unclear and poorly understood. In this study, we investigated the bacterial distribution in disturbed mining areas across three provinces of China, and constructed molecular ecological networks to reveal the interactions among soil bacterial communities in different locations. Furthermore, we examined the relationship between the microbial network topology and environmental factors to show if there is a correlation between the resilience of bacterial community and external pressure. Results: Bacterial community diversity and composition differed dramatically among different locations, such as the semi-humid and semi-arid disturbed mining areas. Additionally, based on the network topology, we distinguished key microbial populations across these mining areas, which belonged to Proteobacteria , Acidobacteria , Actinobacteria , and Chloroflexi . Moreover, the network modules were significantly correlated with some environmental factors, which suggested that microbial interactions might change the soil resilience to the interference resulted from damaged mining areas, then furtherly affect soil ecosystem functions. Conclusions: This study showed that network interactions were completely different across the different mining areas. The keystone species in different mining areas suggested that selected different microbial communities to resist the adverse environment. Moreover, the results of trait-based module significances showed that several environmental factors were significantly correlated with some keystone species. Our study also implied that the complex network of microbial interaction might drive the stand resilience of soil bacteria in the semi-humid and semi-arid disturbed mining areas.

Background: Despite large populations with osteoporosis worldwide, no comprehensive study on the risk factors for different bone loss stages exists. We therefore assessed bone health status and the prevalence of and risk factors for the different bone loss stages. Methods: This cross-sectional study included a representative sample of postmenopausal women and elderly men aged ≥50 years (N=1,412: 1,031 women, 381 men) recruited from eight communities in Guangzhou. All participants underwent measurement of bone mineral density of the lumbar vertebrae and left hip and an assessment of serum bone metabolism parameters. Demographic, clinical, and laboratory data were compared among patients with different bone loss stages. We used univariable and multivariable logistic regression models to explore the risk factors associated with osteopenia or osteoporosis. Findings: The prevalence of osteopenia and osteoporosis was 48·7% and 36·5% in women and 58·3% and 22·3% in men, respectively. For postmenopausal women with normal bone mass, a higher risk of osteoporosis was associated with older age, menstruation duration

Iron(III) in phosphate ore leach liquor harms the quality of phosphoric acid and phosphogypsum crystallization. In this paper, the selective separation of iron(III) was studied with two novel extractants, N, N-n-octylamine di(methylene phenylphosphonic acid) (OADMPPA) and N, N-n-hexadetamine di(methylene phenylphosphonic acid) (HADMPPA), from a mixed media of sulfuric acid and phosphoric acid. The effects of temperature, time, diluents, and the concentrations of sulfuric acid and extractant on the separation of iron were investigated. The mechanism of extraction was established by UV–Vis spectroscopy, FT-IR spectroscopy, slope analysis, and the equimolar series method. The results showed that the two new reagents have good extraction ability toward iron(III) even at higher sulfuric acid concentration. Both OADMPPA and HADMPPA can remove more than 99% of iron(III) from the sulfuric acid leach liquor of phosphate ore. The stripping of iron(III) from the organic phase after extraction with acidic phosphine (phosphorus) extractants was difficult. Oxalic acid was found to be a good stripping agent. The single stage stripping efficiency reached 62.8%, and the two-stage stripping efficiency could reach over 99%. The separation and recovery of iron(III) in phosphate ore leach liquor could be realized by our method without changing the traditional phosphoric acid production process, which is beneficial to the purification of phosphoric acid and the recovery of iron.

In order to reduce the friction and wear of low speed and heavy load sliding bearing and the high temperature phenomenon of stern bearing during sailing, a mathematical model of fluid lubrication between stern shaft and stern bearing was established. Using the rotor bearing system analysis software DLAP (dynamic lubrication analysis program), to solve the Reynolds equation and sticky temperature equation. The influence of oil inlet temperature and inlet pressure on maximum oil film pressure, minimum oil film thickness, temperature rise, power consumption and flow rate between stern shaft and stern bearing are obtained. The results show that the inlet pressure has a great influence on the maximum oil film pressure, minimum film thickness and flow rate. The inlet pressure can be controlled appropriately, which provides a basis for further analysis of lubrication characteristics of stern bearing under different working conditions.

A wet silicon etch chemistry and a process using the chemistry as a simple and cost-effective alternative to the polish/plasma etch silicon thinning process are presented in this paper. The new etch chemistry improves the Si etch rate over traditional etchants such as tetramethylammonium hydroxide (TMAH). The chemistry has very high silicon etch selectivity (ratio of Si etch rate to another film etch rate) over SiO2 and over copper films, with etch selectivity greater than 8000:1 and 2500:1 respectively. Chemical compatibility with typical packaging materials such as polybenzoxazole (PBO) and polyimide (PI) are also discussed. Additionally, real production TSV wafers have been successfully processed on an advanced single wafer etch tool using the chemistry. High uniformity and smooth surface finishing have been achieved.