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The purpose of this paper is to improve the tracking performance of the tracking loops under high dynamic and severe jamming conditions.

First, as the two dominant measurement error sources of the tracking loops, the thermal noise jitter and the dynamic stress error are thoroughly analyzed. Second, a scheme of adaptive tracking loops, which could adaptively adjust the order and the bandwidth of tracking loops, is proposed. Third, real-time detections of the vehicle dynamics and the carrier-to-noise density ratio, and the adaptive bandwidth of the carrier loop are presented, respectively. Finally, simulations are operated to validate the excellent tracking performance of the adaptive tracking loops.

Based on the principle of minimizing the measurement errors, the loop order and bandwidth are adaptively adjusted in the proposed scheme. Thus, the anti-jamming capability and dynamic tracking performance of the tracking loops could be effectively enhanced.

This paper provides further study on the method of improving the tracking capability under complexly applied conditions of high dynamics and severe jamming.

The detections of carrier-to-noise density ratio and vehicle dynamics are used to adaptively adjusting the loop order and bandwidth, which could not only improve the measurement accuracy but also ensure the stable operation of tracking loops.

By studying the green development efficiency (GDE) of 33 cities in the provinces of Jiangsu, Zhejiang, and Fujian in China, this study strives to conduct an analysis of the sustainable practices implemented in these developed regions, and derive valuable insights that can foster the promotion of green transformation.

First, the urban green development system (GDS) was decomposed into the economic benefit subsystem (EBS), social benefit subsystem (SBS), and pollution control subsystem (PCS). Then, a mixed network SBM model was proposed to evaluate the GDE during 20152020, with Moran’s I and Bootstrap truncated regression model subsequently applied to measure the spatial characteristics and driving factors of efficiency.

Subsystem efficiency presents a distribution trend of PCS > EBS > SBS. There is a particular spatial aggregation effect in EBS efficiency, whereas SBS and PCS efficiencies have no significant spatial autocorrelation. Furthermore, urbanization level contributes significantly to the efficiency of all subsystems; industrial structure, energy consumption, and technological innovation play a crucial role in EBS and SBS; external openness is a pivotal factor in SBS; and environmental regulation has a significant effect on PCS.

This study further decomposes the black box of GDS into subsystems including the economy, society, and environment. Additionally, by employing a mixed network SBM model and Bootstrap truncated regression model to investigate efficiency and its driving factors from the subsystem perspective, it endeavors to derive more detailed research conclusions and policy implications.

This paper aims to explore the interplay between industrial diversity and sustainable economic development in US counties.

Among other popularly used measures, this study uses an underused measure, Hachman index, to gauge the degree of industrial diversity in the models. To capture the impact of industrial diversity on the local community, this study estimates the relationship of two diversity measures to four traditional socioeconomic indicators: per capita personal income growth, gross domestic product per worker, income inequality ratio and poverty rate.

Statistical results suggest that industrial diversity, which is measured by Hachman index, is significantly related to the four socio-economic indicators. Industrial diversity can positively contribute to regional per capita personal income growth and mitigate income inequality and poverty stress; however, it is negatively related to the gross domestic product (GDP) per worker, which means industrial specialization may contribute to GDP per worker growth.

The findings of this study show that there is a nonlinear relationship between industrial diversity and all socioeconomic indicators. Most of the control variables, human capital variables and business and industry profile variables also display significant and positive impacts on economic development.

In recent years, sustainability considerations in the real estate sector have moved from being a niche market phenomenon to a mainstream trend. The movement has been accompanied by a shift in the industry’s perception of sustainable buildings. Traditional cost-saving goals are now complemented by a growing interest in the potential for sustainable buildings to tackle broader economic and social sustainability challenges as well as issues related to health and well-being. The real estate industry is increasingly expected to adapt its strategies to incorporate new and more stringent environmental and urban development requirements, to cater to shifting demographics, and to utilize new advancements in construction processes and materials. This chapter explores recent research on sustainable real estate and highlights some of the newest trends in the market. The chapter then examines how policy and technological advancements can enable real estate developers to tackle environmental, social, and economic sustainability challenges. This will be exemplified through a focus on carbon taxation and timber construction. Based on these case studies, the chapter illustrates how today’s sustainable real estate sector – marked by its move beyond a focus on cost savings – requires for building practices to be strongly rooted in global, sustainable development policies.

The transformational prospects of the United Nations' 17 Sustainable Development Goals (SDGs) are doubtless. Nonetheless, finding the appropriate implementation mechanisms to accomplish these goals and their targets and deliver on the promise of Agenda 2030 is proving challenging. Using publicly available documentary evidence from Voluntary National Reviews and Sustainable Development Reports, we analysed the progress of environmental SDG implementation in BRICS (Brazil, Russia, India, China, South Africa) and MINT (Mexico, Indonesia, Nigeria, Turkey) countries. The findings reveal an overall implementation progress level of 64% and 62% in BRICS and MINT, respectively. Relatively, countries in BRICS outperformed their MINT counterparts in five of the six environmental SDGs analysed. Our assessment broadly notes a promising engagement with environmental SDGs in these blocs, albeit with limited progress, and the presence of impressionistic practices in reportage of successes compared with challenges. We highlight the critical environmental goals and areas for practical actions to accomplish Agenda 2030 moving forward. The study specifically draws the attention of policymakers to issues of climate action (SDG13) and affordable and clean energy (SDG7), where immediate actions are needed to ramp up environmental actions. Given the limited time left to accomplish Agenda 2030, the findings of this study provide timely insight into the environmental SDGs that are at risk of failure in these developing countries. The study significantly implicates developing countries' ability to achieve Agenda 2030 and provides practical and actionable policy measures that are urgently needed to address the situation.

The present study provides a comprehensive review of the advancements in five active heating modes for cold-proof clothing as of 2021. It aims to evaluate the current state of research for each heating mode and identify their limitations. Further, the study provides insights into the optimization of intelligent temperature control algorithms and design considerations for intelligent cold-proof clothing.

This article presents a classification of active heating systems based on five different heating principles: electric heating system, solar heating system, phase-change material (PCM) heating system, chemical heating system and fluid/air heating system. The systems are analyzed and evaluated in terms of heating principle, research advancement, scientific challenges and application potential in the field of cold-proof clothing.

The rational utilization of active heating modes enhances the thermal efficiency of cold-proof clothing, resulting in enhanced cold-resistance and reduced volume and weight. Despite progress in the development of the five prevalent heating modes, particularly with regard to the improvement and advancement of heating materials, the current integration of heating systems with cold-proof clothing is limited to the torso and limbs, lacking consideration of the thermal physiological requirements of the human body. Additionally, the heating modes of each system tend to be uniform and lack differentiation to meet the varying cold protection needs of various body parts.

The effective application of multiple heating modes helps the human body to maintain a constant body temperature and thermal equilibrium in a cold environment. The research of heating mode is the basis for realizing the temperature control of cold-proof clothing and provides an effective guarantee for the future development of the intelligent algorithms for temperature control of non-uniform heating of body segments.

The integration of multiple heating modes ensures the maintenance of a constant body temperature and thermal balance for the wearer in cold environments. The research of heating modes forms the foundation for the temperature regulation of cold-proof clothing and lays the groundwork for the development of intelligent algorithms for non-uniform heating control of different body segments.

The present article systematically reviews five active heating modes suitable for use in cold-proof clothing and offers guidance for the selection of heating systems in future smart cold-proof clothing. Furthermore, the findings of this research provide a basis for future research on non-uniform heating modes that are aligned with the thermal physiological needs of the human body, thus contributing to the development of cold-proof clothing that is better suited to meet the thermal needs of the human body.

This study aims to provide a taxonomy of relational benefits that drive customer loyalty in sharing-economy services, assess the relative strengths of these relational benefits in influencing customer loyalty and examine whether commitment mediates the influence of relational benefits on customer loyalty in this context.

Relational benefits of sharing-economy services were explored through a focus group interview, followed by an online survey completed by 440 respondents in China. Structural equation modeling was used to test the hypotheses.

This study shows that confidence and social benefits have significant and positive effects on commitment in sharing-economy services. In addition, safety benefits, a new type of relational benefits, also significantly affect commitment in this context. Furthermore, the findings suggest that commitment acts as a mediator between confidence, social and safety benefits and customer loyalty. Special treatment benefits had no effect on commitment and loyalty in the sharing-economy context.

This paper provides sharing-economy service providers with insight on how to better create and sustain loyal relationships with customers through the provision of relational benefits.

This study offers initial insight into why customers would stay in peer-to-peer relationships in the sharing economy, and suggests how to strengthen relationships between customers and peer service providers.

The purpose of this study is to improve the performance of AISI 430 stainless steel (430 SS) in increasing its oxidation resistance, suppressing coating spalling and cracking, sustaining appropriate conductivity and blocking Cr evaporation as an interconnect material for intermediate temperature solid oxide fuel cells; a protective co-contained coating is formed onto stainless steel via the surface alloying process and followed by thermal oxidation.

In this work, oxidation behavior of coated specimen is studied during isothermal and cyclic oxidation measurements. Moreover, the conductivity is also investigated by area specific resistance (ASR) measurement.

Co-contained spinel layer shows an outstanding performance in preventing oxidation and improving conductivity compared with uncoated specimens. The protective spinel coating also reduces the ASR for coated specimen (0.0576O cm²) as compared to the uncoated specimen (1.87296O cm²) after isothermal oxidation.

The probable mechanism of co-contained alloy converting into spinel and the spinel transfer electron is presented.

Selective laser melting and electron beam melting processes are well-known for the additive manufacturing of metal parts. Metal powder bed fusion (MPBF) is a common term for them. The MPBF process can empower the manufacturing of intricate shapes by reducing the use of special tools, shortening the supply chain and allowing small batches. However, the MPBF process suffers from many quality issues. In literature, several works are recorded for qualification of the MPBF part. The purpose of this study is to recollect those works done for quality control and report their helpful findings for further research and development.

A systematic literature review was conducted to highlight the major quality issues in the MPBF process and its root causes. Further, the works reported in the literature for mitigation of these issues are classified and discussed in five categories: experimental investigation, finite element method-based numerical models, physics-based analytical models, in-situ control using artificial intelligence (AI) and machine learning (ML) methods and statistical approaches. A comparison is also prepared among these strategies based on their suitability and limitations. Additionally, improvements in MPBF printers are pointed out to enhance the part quality.

Analytical models require less computational time to simulate the MPBF process and need a smaller number of experiments to confirm the results. They can be used as an efficient process parameter planning tool to print metal parts for noncritical applications. The AI-ML based quality control is also suitable for MPBF processes as it can control many processing parameters that may affect the quality of the MPBF part. Moreover, capabilities of MPBF printers like thinner layer thickness, smaller beam diameter, multiple lasers and high build temperature range can help in quality control.

This study converts the piecemeal data on MPBF part qualification methods into interesting information and presents it in tabular form under each strategy. This tabular information provides the basis for further quality improvement efforts in the MPBF process.

This study references researchers and practitioners on recent quality control efforts and their significant findings for a better quality of MPBF part.

The present study is undertaken in the region of Guelma that is located in North-Eastern Algeria. Guelma’s agricultural plain is irrigated from the Seybouse ephemeral river (wadi). The latter collects the entire domestic and industrial wastewaters of the region that are discharged without prior treatment. Hence, the organic and biological or what so ever contributions to the wadi are capable of initiating a significant degradation of its waters’ quality and challenging their use for irrigation. The paper aims to discuss these issues.

The interpretation of the results of three sampling campaigns for chemical and bacteriological analyzes was carried out in terms of the indices’ method (organic pollution index (OPI) and microbiological quality index (MQI)). The results were statistically assessed through the use of the principal component analysis (PCA). The OPI was calculated according to the method of Leclercq and Maquet (1987) whose principle is to classify the contents for the polluting elements into 5 classes each class corresponding to a given range for the considered parameter, and then to calculate the overall average class number for each sample. The MQI depends on the water concentrations in: the total coliforms, the fecal coliforms, and fecal streptococci. One defines five classes of concentrations for each of these parameters. The MQI is again the overall mean of the numbers for the classes for every parameter.

The OPI reflects a moderate pollution for most sampling stations. The PCA indicates that the variables controlling salinity are mainly Cl⁻, Na⁺ and SO₄²⁻. In August 2016, El-Fedjoudj pumping station shows a very strong fecal contamination. According to the recommendations of World Health Organization (1989), waters from wadi Seybouse cannot be used for the irrigation of vegetable crops if they were to be consumed raw.

This study has an environment impact as it reveals the need to protect surface waters used for irrigation and therefore protect consumers of raw vegetables that are to be consumed uncooked.