Cooperative System Research Articles

Maintaining disorder: estimating the association between policing and psychiatric hospitalization among youth in New York City by neighborhood racial composition, 2006-2014.

To assess whether neighborhood-level measures of policing are spatio-temporally associated with psychiatric hospialization among adolescents and young adults in New York City, and whether this association varies by neighborhood racial composition. We derived population-based measures of policing from the New York City Police Department (NYPD), psychiatric hospitalization from Statewide Planning and Research Cooperative System (SPARCS) data, and socio-demographic data from the American Community Survey (ACS), aggregated by month and ZIP Code Tabulation Area (ZCTA) from 2006 to 2014. Multi-level negative binomial regression models assessed hospitalization-time of youth aged 10-24 as the dependent variable and the rate of policing events as the primary independent variable, adjusting for neighborhood poverty, unemployment, and educational attainment. Multiplicative interaction was assessed between policing and tertiles of the percentage of Black residents. A total of 11,900,192 policing incidents and 2,118,481 person-days of hospitalization were aggregated to 19,440 ZCTA-months. After adjusting for neighborhood-level sociodemographic characteristics, an increase in one policing incident per 1,000 residents was associated with a 0.3% increase in the rate of youth psychiatric hospitalization time (IRR 1.003 [1.001-1.005]). Neighborhood racial composition modified this effect; not only was the rate of psychiatric hospitalization and policing higher in neighborhoods with a higher proportion of Black residents, but the association between these was also significantly higher in neighorhoods with a larger share of Black residents compared with predominantly non-Black neighborhoods. Neighborhoods experiencing higher rates of policing during the study period experienced higher burdens of psychiatric hospitalization among adolescent and young adult residents. This association was larger in neighborhoods of color which have been disproportionately targeted by "hot spot" and order-maintenance policing practices and policies.

Patients With a History of Lumbar Fusion Have a Greater Risk of Revision Arthroscopy and Conversion to Total Hip Arthroplasty After Primary Hip Arthroscopy

PurposeTo characterize the risk of revision hip arthroscopy or conversion to total hip arthroplasty (THA) among patients with a history of lumbar fusion undergoing primary hip arthroscopy. MethodsWe used the Statewide Planning and Research Cooperative System, an administrative database including all ambulatory and inpatient surgery encounters in New York (NY), to identify all patients who underwent hip arthroscopy for FAI between 2010–2020. Patients with prior lumbar fusion were identified using CPT and ICD 9th/10th Revision coding definitions. Patients with and without prior fusion were matched in a 1:5 ratio according to age and comorbidity burden. The number of levels fused was defined in the following fashion: i) no fusion, ii) 1-2 levels, or iii) ≥3 levels. Patients were followed for two years to evaluate the rate of revision hip arthroscopy or conversion to THA. Multivariable logistic regression models were used to measure the association between number of levels fused and revision hip arthroscopy or conversion to THA. ResultsBetween 2010–2020, there were 23,277 patients that underwent primary hip arthroscopy in NY state. Of these, 348 (1.4%) had a prior lumbar fusion. After matching for age and comorbidities, the composite rate of revision hip arthroscopy or conversion to THA was higher in patients with prior lumbar fusion compared to patients without (16.5% vs. 8.5%; P < 0.001). This risk increased with the number of levels fused (1-2 levels: 15.1%; aOR, 1.8; 95% CI, 1.3–2.6; vs. ≥3 levels: 26.3%; aOR, 3.4; 95% CI, 1.7–7.0). ConclusionPatients with a history of lumbar fusion had significantly higher rates of revision hip arthroscopy and conversion to THA compared to patients without prior fusion. The risk of revision hip arthroscopy or conversion to THA was increased approximately 2-fold in patients with 1-2 levels fused and 3-fold in patients with 3 or more levels fused. Level of EvidenceLevel III, prognostic retrospective matched comparative case series.

Do Social Deprivation and Surgical Volume Influence Outcomes Following Distal Radius Fracture Fixation?

Distal radius fractures account for nearly 25% of fractures in adults, with a trend toward operative fixation. The objective of this study was to assess the relationship between surgeon and hospital volume with complications following distal radius fixation. A retrospective study was performed using the New York Statewide Planning and Research Cooperative System database from 2009 to 2015. Outpatient claims were identified for distal radius fractures and surgery. The facility and surgeon's identifier were used to calculate annual procedure volume. The risk for infection, carpal tunnel surgery, and revision/hardware removal was analyzed, and Social Deprivation Index (SDI) was linked to each patient. Patient demographics and rate of complications were compared across hospital and physician volume. A total of 14 748 patients were included, finding Federal and self-pay insurance associated with low-volume (LV) facility care and private insurance with high-volume (HV) facilities. The SDI for patients treated by LV surgeons and hospitals was significantly higher compared with HV providers. Low-volume facilities and surgeons had a higher 3-month risk of infection requiring reoperation. High-volume facilities were less likely to treat Hispanic patients, those with comorbidities, higher SDI, and with Federal or self-pay insurance. Patients treated by LV surgeons and facilities had a higher risk of infection requiring surgery within 3 months than those treated by HV providers. Low-volume facilities were more likely to treat patients who were Hispanic, Federally insured, and with comorbidities and higher SDI than HV facilities, increasing their risk for disadvantaged care. Level III.

Predicting hospital length of stay using machine learning on a large open health dataset

BackgroundGovernments worldwide are facing growing pressure to increase transparency, as citizens demand greater insight into decision-making processes and public spending. An example is the release of open healthcare data to researchers, as healthcare is one of the top economic sectors. Significant information systems development and computational experimentation are required to extract meaning and value from these datasets. We use a large open health dataset provided by the New York State Statewide Planning and Research Cooperative System (SPARCS) containing 2.3 million de-identified patient records. One of the fields in these records is a patient’s length of stay (LoS) in a hospital, which is crucial in estimating healthcare costs and planning hospital capacity for future needs. Hence it would be very beneficial for hospitals to be able to predict the LoS early. The area of machine learning offers a potential solution, which is the focus of the current paper.MethodsWe investigated multiple machine learning techniques including feature engineering, regression, and classification trees to predict the length of stay (LoS) of all the hospital procedures currently available in the dataset. Whereas many researchers focus on LoS prediction for a specific disease, a unique feature of our model is its ability to simultaneously handle 285 diagnosis codes from the Clinical Classification System (CCS). We focused on the interpretability and explainability of input features and the resulting models. We developed separate models for newborns and non-newborns.ResultsThe study yields promising results, demonstrating the effectiveness of machine learning in predicting LoS. The best R2 scores achieved are noteworthy: 0.82 for newborns using linear regression and 0.43 for non-newborns using catboost regression. Focusing on cardiovascular disease refines the predictive capability, achieving an improved R2 score of 0.62. The models not only demonstrate high performance but also provide understandable insights. For instance, birth-weight is employed for predicting LoS in newborns, while diagnostic-related group classification proves valuable for non-newborns.ConclusionOur study showcases the practical utility of machine learning models in predicting LoS during patient admittance. The emphasis on interpretability ensures that the models can be easily comprehended and replicated by other researchers. Healthcare stakeholders, including providers, administrators, and patients, stand to benefit significantly. The findings offer valuable insights for cost estimation and capacity planning, contributing to the overall enhancement of healthcare management and delivery.

Development of inter-territorial interaction and cooperation in the field of waste management

Aim. To build a system of inter-territorial interaction and cooperation in the sphere of waste management.Objectives. To develop a model of interterritorial interaction and cooperation in the sphere of waste management; to offer directions and forms of interterritorial interaction and cooperation in the investigated sphere.Methods. The author used the methods of analysis and synthesis, generalization and classification, as well as modeling. Legislative acts of the Russian Federation (RF), data of official governmental sites of the RF and the Republic of Bashkortostan, scientific articles, monographs, periodicals in the field of ecological monitoring of territories, data of the public-law company “Russian Ecological Operator” (PPC “REO”), statistical collections devoted to the researched subject served as a methodological basis for model building.Results. The author of the article proposes a model of inter-territorial interaction and cooperation, which includes the definition of ratings of regions, forms and directions, assessment of risks and effectiveness of inter-territorial interaction and cooperation. It is argued that interaction and cooperation in this area can be realized through participation in investment for the creation of infrastructure facilities for waste management; through participation in tenders on the electronic trading platform for the purchase of secondary raw materials; construction of eco-industrial parks, allowing to reduce to the maximum the amount of waste going to landfill; awareness-raising activities to popularize the principles of closed-cycle economy; eco-volunteering, creation of an eco-monitoring system.Conclusions. The model of interterritorial interaction and cooperation in the sphere of waste management proposed by the author allows to improve its quality, to ensure the efficiency of territorial development, viability of waste management infrastructure, full utilization of the potential of regions and the sphere of waste management.

Knowledge based interventions for sustainable development cooperation: insights from knowledge systems mapping in Zambia

Knowledge is an essential determinant and component of the international development cooperation agenda and projects. Therefore, it is vital to understand and reflect on how knowledge in international development cooperation is created, what knowledge counts, and how it influences the planning, implementation, and outcomes of international development cooperation projects. In this paper, we critically examine the knowledge system of the development cooperation of the Czech Republic, an emerging donor country, by applying system theory and utilizing system properties as an analytical tool. To this end, we carried out a multi-phase qualitative research with actors from the Czech Republic and Zambia. Subsequently, we analysed the knowledge system properties and identified those often overlooked by development actors, such as taboos, mistrust, and development burden, revealing how knowledge flows can be obstructed by these characteristics. In addition, we compiled a set of suitable interventions to tackle the overlooked system properties and foster knowledge cross-fertilisation. These interventions include, among others, active engagement of traditional leaders, active work with narratives of success, and introducing action-reflection-reaction cycle into the development practice. Furthermore, the proposed interventions clearly emphasize the need for more collaborative and transdisciplinary processes. Finally, we discuss that it is essential to uncover deep layers of the international development cooperation knowledge system to shift and leverage it towards more inclusive and just outcomes.

Identification methods for ordinal potential differential games

This paper introduces two new identification methods for linear quadratic (LQ) ordinal potential differential games (OPDGs). Potential games are notable for their benefits, such as the computability and guaranteed existence of Nash Equilibria. While previous research has analyzed ordinal potential static games, their applicability to various engineering applications remains limited. Despite the earlier introduction of OPDGs, a systematic method for identifying a potential game for a given LQ differential game has not yet been developed. To address this gap, we propose two identification methods to provide the quadratic potential cost function for a given LQ differential game. Both methods are based on linear matrix inequalities (LMIs). The first method aims to minimize the condition number of the potential cost function’s parameters, offering a faster and more precise technique compared to earlier solutions. In addition, we present an evaluation of the feasibility of the structural requirements of the system. The second method, with a less rigid formulation, can identify LQ OPDGs in cases where the first method fails. These novel identification methods are verified through simulations, demonstrating their advantages and potential in designing and analyzing cooperative control systems.

Design of New BLE GAP Roles for Vehicular Communications.

Bluetooth Low Energy (BLE) is a prominent short-range wireless communication protocol widely extended for communications and sensor systems in consumer electronics and industrial applications, ranging from manufacturing to retail and healthcare. The BLE protocol provides four generic access profile (GAP) roles when it is used in its low-energy version, i.e., ver. 4 and beyond. GAP roles control connections and allow BLE devices to interoperate each other. They are defined by the Bluetooth special interest group (SIG) and are primarily oriented to connect peripherals wirelessly to smartphones, laptops, and desktops. Consequently, the existing GAP roles have characteristics that do not fit well with vehicular communications in cooperative intelligent transport systems (C-ITS), where low-latency communications in high-density environments with stringent security demands are required. This work addresses this gap by developing two new GAP roles, defined at the application layer to meet the specific requirements of vehicular communications, and by providing a service application programming interface (API) for developers of vehicle-to-everything (V2X) applications. We have named this new approach ITS-BLE. These GAP roles are intended to facilitate BLE-based solutions for real-world scenarios on roads, such as detecting road traffic signs or exchanging information at toll booths. We have developed a prototype able to work indistinctly as a unidirectional or bidirectional communication device, depending on the use case. To solve security risks in the exchange of personal data, BLE data packets, here called packet data units (PDU), are encrypted or signed to guarantee either privacy when sharing sensitive data or authenticity when avoiding spoofing, respectively. Measurements taken and their later evaluation demonstrated the feasibility of a V2X BLE network consisting of picocells with a radius of about 200 m.

Negotiated Agreements as an Alternative to Criminal Trials: Policy Lessons from the Hungarian Example

Abstract This paper looks at ways of speeding up domestic criminal proceedings. Both the Charter of Fundamental Rights of the European Union and the case law of the European Court of Human Rights in Strasbourg encourage Member States to ensure that their courts deliver judgments within a reasonable time. The present paper deals with the new Hungarian cooperation system, including the trial waiver and the preparatory session, which is a pre-trial meeting in the court phase. These have achieved significant results in speeding up and simplifying proceedings without limiting the rights of the accused and offer a genuine rule of law solution for efficient criminal proceedings, all while preventing unjustified delays in proceedings. Initial experience in practice has shown that these Hungarian legal instruments could serve as an excellent example for countries facing similar challenges in developing criminal politics and criminal justice policies.

Power Outages: An Underappreciated Risk Factor for Children's Carbon Monoxide Poisoning.

Children's risk of exposure to carbon monoxide (CO) increases after disasters, likely due to improper generator use during power outages. Here, we evaluate the impact of outages on children's CO-related emergency department (ED) visits in New York State (NYS). We leveraged power outage data spanning 2017-2020 from the NYS Department of Public Service for 1,865 power operating localities (i.e., communities) and defined all-size and large-scale power outage hours. All-size outage hours affected ≥1% of customers, and large-scale outage hours affected ≥20%. We identified CO poisoning using diagnostic codes among those aged <18 between 2017 and 2020 using the Statewide Planning and Research Cooperative System (SPARCS), an all-payer reporting system in NYS. We linked community power outage exposure to patients using the population-weighted centroid of their block group of residence. We estimated the impact of power outages on CO poisoning using a time-stratified case-crossover study design with conditional logistic regression, controlling for daily relative humidity, mean temperature, and total precipitation. Analyses were stratified by urban and rural communities. From 2017-2020, there were 917 pediatric CO poisoning ED visits in NYS. Most cases (83%) occurred in urban region of the state. We observed an association statewide between all-size and large-scale outages and CO ED visits on the index day and the following two days before a return to baseline on lag day 3. Four hours without power increased the odds of a pediatric CO poisoning ED visit by ≥50% for small-scale and ≥150% for large-scale outages, and associations were stronger in urban versus rural areas. While CO poisoning is a relatively rare cause of pediatric ED visits in NYS, it can be deadly and is also preventable. Expanded analyses of the health impacts of outages and advocacy for reliable energy access are needed to support children's health in a changing climate.

Customs and logistics infrastructure in the system of international cooperation

The article considers the logistical elements of the infrastructure under which the transportation of goods of domestic orientation and international level is carried out. Modern logistics chains are changing their course, and Russia is turning its attention to the development of transport corridors of the eastern direction.

Mission-critical UAV swarm coordination and cooperative positioning using an integrated ROS-LoRa-based communications architecture

Over the recent years unmanned aerial vehicles (UAVs) have been utilized extensively in mission-critical operations, especially as it relates to disaster management scenarios. Clearly, during these missions, the UAVs should be able to communicate effectively (amongst themselves and with the ground control station (GCS)) in order to transmit and receive commands and other related information. Moreover, accurate positioning is paramount during this type of operations. This has motivated the exploration of a number of alternative navigation methods to address robustness issues that arise when the global positioning system (GPS) becomes unavailable, due to GNSS disruption or sensor malfunction. This work addresses these issues by initially developing and implementing an integrated LoRa-ROS-based (long range communication - robot operating system) system for UAV-to-X communications. Subsequently, it presents a novel cooperative positioning approach, where a group of autonomous UAVs employ various algorithms (detection, tracking, communication, and localization) for cooperative positioning in order to counter any GPS/sensor malfunction. For evaluation purposes, a prototype multi-agent system is designed and implemented, utilizing the proposed integrated ROS-LoRa-based communication architecture, as well as sensor (inertial measurement unit - IMU) fusion. Specifically, LoRA mesh networking (using a custom printed circuit board - BALORA), is incorporated to maintain communication and distribute the sensor information between the UAVs. The prototype of the proposed communications architecture and cooperative relative positioning system (CRPS) is subsequently tested in a real-world environment, demonstrating the feasibility and effectiveness of the proposed communications solution, as well as the robust and accurate localization that is analogous to the ground truth (GPS+IMU).

PM2.5 and its components and respiratory disease healthcare encounters – Unanticipated increased exposure-response relationships in recent years after environmental policies

Prior studies reported excess rates (ERs) of cardiorespiratory events associated with short-term increases in PM2.5 concentrations, despite implementation of pollution-control policies. In 2017, Federal Tier 3 light-duty vehicle regulations began, and to-date there have been no assessments of population health effects of the policy. Using the NYS Statewide Planning and Research Cooperative System (SPARCS) database, we obtained hospitalizations and ED visits with a principal diagnosis of asthma or chronic obstructive pulmonary disease (COPD) for residents living within 15 miles of six urban PM2.5 monitoring sites in NYS (2014–2019). We used a time-stratified case-crossover design and conditional logistic regression (adjusting for ambient temperature, relative humidity, and weekday) to estimate associations between PM2.5, POC (primary organic carbon), SOC (secondary organic carbon), and rates of respiratory disease hospitalizations and emergency department (ED) visits from 2014 to 2019. We evaluated demographic disparities in these relative rates and compared changes in ERs before (2014–2016) and after Tier 3 implementation (2017–2019). Each interquartile range increase in PM2.5 was associated with increased ERs of asthma or COPD hospitalizations and ED visits in the previous 7 days (ERs ranged from 1.1%–3.1%). Interquartile range increases in POC were associated with increased rates of asthma ED visits (lag days 0–6: ER = 2.1%, 95% CI = 0.7%, 3.6%). Unexpectedly, the ERs of asthma admission and ED visits associated with PM2.5, POC, and SOC were higher during 2017–2019 (after Tier 3) than 2014–2016 (before Tier-3). Chronic obstructive pulmonary disease analyses showed similar patterns. Excess Rates were higher in children (<18 years; asthma) and seniors (≥65 years; COPD), and Black, Hispanic, and NYC residents. In summary, unanticipated increases in asthma and COPD ERs after Tier-3 implementation were observed, and demographic disparities in asthma/COPD and PM2.5, POC, and SOC associations were also observed. Future work should confirm findings and investigate triggering of respiratory events by source-specific PM.

A Method for Multi-AUV Cooperative Area Search in Unknown Environment Based on Reinforcement Learning

As an emerging direction of multi-agent collaborative control technology, multiple autonomous underwater vehicle (multi-AUV) cooperative area search technology has played an important role in civilian fields such as marine resource exploration and development, marine rescue, and marine scientific expeditions, as well as in military fields such as mine countermeasures and military underwater reconnaissance. At present, as we continue to explore the ocean, the environment in which AUVs perform search tasks is mostly unknown, with many uncertainties such as obstacles, which places high demands on the autonomous decision-making capabilities of AUVs. Moreover, considering the limited detection capability of a single AUV in underwater environments, while the area searched by the AUV is constantly expanding, a single AUV cannot obtain global state information in real time and can only make behavioral decisions based on local observation information, which adversely affects the coordination between AUVs and the search efficiency of multi-AUV systems. Therefore, in order to face increasingly challenging search tasks, we adopt multi-agent reinforcement learning (MARL) to study the problem of multi-AUV cooperative area search from the perspective of improving autonomous decision-making capabilities and collaboration between AUVs. First, we modeled the search task as a decentralized partial observation Markov decision process (Dec-POMDP) and established a search information map. Each AUV updates the information map based on sonar detection information and information fusion between AUVs, and makes real-time decisions based on this to better address the problem of insufficient observation information caused by the weak perception ability of AUVs in underwater environments. Secondly, we established a multi-AUV cooperative area search system (MACASS), which employs a search strategy based on multi-agent reinforcement learning. The system combines various AUVs into a unified entity using a distributed control approach. During the execution of search tasks, each AUV can make action decisions based on sonar detection information and information exchange among AUVs in the system, utilizing the MARL-based search strategy. As a result, AUVs possess enhanced autonomy in decision-making, enabling them to better handle challenges such as limited detection capabilities and insufficient observational information.

Diversity-multiplexing tradeoff for cooperative MIMO radar and communications system

In this paper, multiple-input multiple-output (MIMO) integrated radar and communications (IRC) system is studied, where the radar and communications parts work cooperatively, leading to a hybrid active-passive (HAP) MIMO radar and a radar-aided (RA) MIMO communications subsystems. To unify the performance metric for both subsystems, the diversity gain and multiplexing gain are derived for the RA MIMO communications and the HAP MIMO radar subsystems, based on which the tradeoff between the diversity and multiplexing gains is analyzed theoretically for each of the subsystems. The obtained diversity gain and multiplexing gain can facilitate the design and optimization of the IRC system. Employing these two unified performance metrics, the IRC system antenna number assignment is formulated as a multi-objective optimization problem, and the Pareto solutions are provided. The correctness of theoretical analysis is verified by simulations. Our results can provide useful guidance for system designers.

Protocell Effects on RNA Folding, Function, and Evolution.

ConspectusCreating a living system from nonliving matter is a great challenge in chemistry and biophysics. The early history of life can provide inspiration from the idea of the prebiotic "RNA World" established by ribozymes, in which all genetic and catalytic activities were executed by RNA. Such a system could be much simpler than the interdependent central dogma characterizing life today. At the same time, cooperative systems require a mechanism such as cellular compartmentalization in order to survive and evolve. Minimal cells might therefore consist of simple vesicles enclosing a prebiotic RNA metabolism.The internal volume of a vesicle is a distinctive environment due to its closed boundary, which alters diffusion and available volume for macromolecules and changes effective molecular concentrations, among other considerations. These physical effects are mechanistically distinct from chemical interactions, such as electrostatic repulsion, that might also occur between the membrane boundary and encapsulated contents. Both indirect and direct interactions between the membrane and RNA can give rise to nonintuitive, "emergent" behaviors in the model protocell system. We have been examining how encapsulation inside membrane vesicles would affect the folding and activity of entrapped RNA.Using biophysical techniques such as FRET, we characterized ribozyme folding and activity inside vesicles. Encapsulation inside model protocells generally promoted RNA folding, consistent with an excluded volume effect, independently of chemical interactions. This energetic stabilization translated into increased ribozyme activity in two different systems that were studied (hairpin ribozyme and self-aminoacylating RNAs). A particularly intriguing finding was that encapsulation could rescue the activity of mutant ribozymes, suggesting that encapsulation could affect not only folding and activity but also evolution. To study this further, we developed a high-throughput sequencing assay to measure the aminoacylation kinetics of many thousands of ribozyme variants in parallel. The results revealed an unexpected tendency for encapsulation to improve the better ribozyme variants more than worse variants. During evolution, this effect would create a tilted playing field, so to speak, that would give additional fitness gains to already-high-activity variants. According to Fisher's Fundamental Theorem of Natural Selection, the increased variance in fitness should manifest as faster evolutionary adaptation. This prediction was borne out experimentally during in vitro evolution, where we observed that the initially diverse ribozyme population converged more quickly to the most active sequences when they were encapsulated inside vesicles.The studies in this Account have expanded our understanding of emergent protocell behavior, by showing how simply entrapping an RNA inside a vesicle, which could occur spontaneously during vesicle formation, might profoundly affect the evolutionary landscape of the RNA. Because of the exponential dynamics of replication and selection, even small changes to activity and function could lead to major evolutionary consequences. By closely studying the details of minimal yet surprisingly complex protocells, we might one day trace a pathway from encapsulated RNA to a living system.

Stability analysis of homogeneous cooperative positive differential systems with time-varying delays and its generalization

This article is devoted to studying the asymptotic behavior of differential systems with bounded delays. We first focus on the analysis of homogeneous cooperative positive systems. Under the assumption that the vector field is homogeneous of a degree greater than 1, we show that the non-trivial solutions of the system converge to the origin at a polynomial rate. In the case when the degree of homogeneity equals 1, we prove that the solutions will decay at an exponential rate. As a generalization of these results, we consider nonlinear non-autonomous differential systems with time-varying delays that are bounded above by stable homogeneous positive systems. By some additional imposed conditions, in light of the comparison principle, we obtain the locally exponential stability and polynomial stability of the equilibrium point to these systems. Finally, specific examples and discussions are provided to illustrate the validity of the proposed theoretical results.

Outage probability analysis for downlink NOMA ARS-assisted cooperative communication system with trajectory optimization

In this paper, we propose and investigate the performance of a downlink non-orthogonal multiple access multi-user system with the assistance of an aerial relay station (ARS). The ARS is equipped with multiple antennas, mounted on an unmanned aerial vehicle (UAV), and serves as a relay for cooperative communication between a terrestrial base station (BS) and users. The system performance is evaluated via the outage probability of each user in the urban environment where the ARS and BS are configured with a different number of antennas. More interestingly, the optimization of the ARS trajectory to maximize the data rate of the considered system is also proposed by using the successive convex approximation technique. The results show that the best system performance can be obtained by adjusting the altitude and designing the optimum trajectory of the ARS. Monte-Carlo simulation results are provided to demonstrate the performance of the proposed system and the accuracy of the developed analytical frameworks.

The Twilight of the Law of the Fairs: Inventing International Cooperation on Bankruptcies in Early Modern Europe (Lyon, 1660–1710)

Abstract Bankruptcy was a key institution in the development of markets in Europe. However, the territoriality of jurisdictions and legal systems made international insolvencies difficult to manage. In the middle of the seventeenth century, cities such as Lyon developed networks of cooperation by granting foreign merchants equal rights to local creditors on a reciprocal basis. However, courts were reluctant to give foreign authorities control over assets and creditors on their territory. The article examines how the Lyon commercial court changed its policy towards international insolvencies during the second half of the seventeenth century. Whereas equal treatment of foreign creditors was conditioned on the recognition of an extraterritorial jurisdiction in the medieval fairs system, it now depended on the reciprocity of the legal status granted to merchants abroad. This system of cooperation between equally sovereign courts prefigured in many ways the current situation of private international law in bankruptcy matters.

Regional Projects as Autonomous and Cooperative Systems: The Case of the Ishikari Area

Regional Projects as Autonomous and Cooperative Systems: The Case of the Ishikari Area