Unique Problem Research Articles

Hierarchical Stackelberg Control for a Two-Stroke Linear System in Population Dynamics

We study a unique hierarchical control problem for a two-stoke linear system, adjoint to an age and space dependent population dynamics problem. Using Stackelberg's method, we introduce two levels of control: a boundary control to achieve optimal flow regulation and a distributed control for null controllability. Our approach employs Carleman inequalities to address non-homogeneous Dirichlet boundary conditions, leading to new insights in controlling invasive species populations. These results highlight the applicability of hierarchical controls in ecological systems, providing a robust framework for future studies in control theory and population dynamics.

Trading in the Quantum Era: optimizing Bitcoin gains and energy costs

ABSTRACT This paper presents an in-depth analysis of a Quantum-inspired Multi-objective Optimization Algorithm (QMOA) applied to a unique problem: maximizing trading profits while minimizing energy costs. Previous investigations have explored the profitability of Bitcoin, yet our research delves into its relationship with energy costs. Regarding the trade-offs, the Pareto analysis reveals that trading profit and energy cost do not strongly inversely correlate. The range of outcomes shows a relatively uniform trading profit (from 1.302,85 to 1.310,22$), but a broader variation in energy costs (from 1.141,66 to 5.657,94$). While the trading profit remains stable, there is a wide array of options for minimizing energy cost, which is influenced by various constraints and market conditions. Solutions tend to cluster more in areas of higher energy costs. However, the variability in energy costs offers Bitcoin miners choices, allowing them to tailor strategies, whether that involves prioritizing energy efficiency, profit maximization or striking a balance.

Estimation of Contact Time Among Animals from Telemetry Data

Continuous processes in most applications are measured discretely with error. This complicates the task of detecting intersections and the number of intersections between two continuous processes (i.e., when the processes have the same value). Intersections of continuous processes are scientifically important, but challenging to estimate from data. For example, in the field of animal ecology, intersections of the paths of moving animals tracked with satellite technologies can be used to understand disease transmission. We illustrate how to quantify contact between animals using telemetry data (i.e., the recorded locations of an animal over time). We introduce our method to quantify contact time with accessible concepts from introductory stochastic process literature, such as Brownian motion. Then, we provide two data examples using white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus) telemetry data in a region with high prevalence of chronic wasting disease. Our work provides a needed connection between existing model-based literature for animal movement and rule-based literature for animal interaction. Further, our work illustrates a unique statistical problem receiving minimal attention with broad applicability in human and livestock tracking.

Finite Element Analysis in The Investigation of Methods to Model AC Resistance in A Coated Conductor

In our electricity dependent and rapidly automated society, the manipulation and usage of electricity to transmit energy is of significant prevalence. In particular, the application of current in high frequency transformers, inductors and motor generators presents a unique efficiency problem: The loss of energy through the spiking of effective resistance intrinsically related to the skin and proximity effects of an AC current. By the usage of Finite Element Analysis (FEA) in the simulative investigation of various variables on AC resistance, this paper seeks to provide insights into how coated conductors might offer advantages over the standard conductor in certain conditions, thus guiding future design and application in high-efficiency electronics. The papers findings reveal that adding a layer of coating with a lower conductivity than the core material could offer reduced energy losses up to the point when the skin depth matches the coating’s thickness. Moreover, the study explored the influence of the coating’s conductivity, suggesting that an increased conductivity of the coating material could further minimize copper losses, albeit with the trade-off of potentially higher costs. The study concludes with a Taylor Series approximation of the relationship between AC resistance and frequency using simulative data.

Hierarchy of environmental impacts in hydroelectric projects established in mountain ecosystems

In Bolivia, hydroelectric projects are gaining relevance as a source of renewable energy, which is why there is little record of specific experiences on the implementation of hydroelectric projects in mountain areas that include an analysis of the environment within the framework of sustainability energetic. The present study takes a hydroelectric reservoir project established in a mountain ecosystem as a unit of analysis to demonstrate that a hierarchy of environmental impacts responds more precisely to the environmental dimension, according to its technical and ecosystem characteristics. The development of the work starts with the analysis of the information recorded in the Environmental Impact Assessment Study - EEIA and based on this information, a procedure is carried out to rank the environmental impacts with the use of matrix, qualitative and quantitative methods, in addition to the use of specialized software. Finally, it is concluded that there are no standard evaluations, and it is affirmed that the EIA of any hydro-energy project, whether established or not, in a mountain ecosystem, is a complex and unique problem. Therefore, a hierarchical ranking of environmental impacts in an initial and particular way to the project site area contributes in a real and effective way to an environmental sustainability of the intervened ecosystem, within the framework of Sustainable Energy Development.

Preserved walking function without postoperative reconstruction for pelvic Ewing’s sarcoma: a case report

BackgroundEwing’s sarcoma is a primary bone tumor predominantly observed in children and adolescents, necessitating a multidisciplinary treatment approach. While localized cases have a 5-year survival rate of 60–70%, the prognosis is significantly worse in pelvic advanced cases with metastasis. Moreover, pelvic Ewing’s sarcoma has the unique problem of leading to high rates of postoperative infection.Case presentationWe present the case of a Japanese 14-year-old boy with left iliac Ewing’s sarcoma and multiple metastases. At the initial visit, imaging revealed a large tumor in the left iliac bone with extraosseous extension and metastasis to multiple sites. Neoadjuvant chemotherapy resulted in significant tumor reduction. Surgical resection was performed without pelvic ring reconstruction to enable early postoperative chemotherapy and minimize postoperative infection risk. Despite complete abductor muscle removal, the patient achieved a stable gait postoperatively by centering the load axis.ConclusionOur case highlights the successful management of a left iliac Ewing’s sarcoma with multiple metastases, with a focus on functional preservation and infection risk reduction. Pelvic ring reconstruction was not performed to avoid postoperative complications, emphasizing the importance of early postoperative chemotherapy. The patient achieved a stable gait postoperatively, demonstrating the potential benefits of this approach in similar cases.

Finite element approximation of unique continuation of functions with finite dimensional trace

We consider a unique continuation problem where the Dirichlet trace of the solution is known to have finite dimension. We prove Lipschitz stability of the unique continuation problem and design a finite element method that exploits the finite dimensionality to enhance stability. Optimal a priori and a posteriori error estimates are shown for the method. The extension to problems where the trace is not in a finite dimensional space, but can be approximated to high accuracy using finite dimensional functions is discussed. Finally, the theory is illustrated in some numerical examples.

Per-Instance Algorithm Configuration in Homogeneous Instance Spaces: A Use Case in Reconfigurable Assembly Systems

The physical capabilities of a reconfigurable assembly system (RAS) increase the agility and responsiveness of the system in highly volatile market conditions. However, achieving optimal RAS utilization entails solving complex optimization problems effectively and efficiently. These optimizations often define homogenous sets of problem instances. While algorithm configuration in such homogeneous contexts traditionally adopts a “one-size-fits-all” approach, recent studies have shown the potential of per-instance algorithm configuration (PIAC) methods in these settings. In this work, we evaluate and compare the performance of different PIAC methods in this context, namely Hydra—a state-of-the-art PIAC method—and a simpler case-based reasoning (CBR) approach. We evaluate the impact of the tuning time budget and/or the number of unique problem instances used for training on each of the method’s performance and robustness. Our experiments show that whilst Hydra fails to improve upon the default algorithm configuration, the CBR method can lead to 16% performance increase using as few as 100 training instances. Following these findings, we evaluate Hydra’s methodology when applied to homogenous instance spaces. This analysis shows the limitations of Hydra’s inference mechanisms in these settings and showcases the advantages of distance-based approaches used in CBR.

Secondary Analysis of Human Bulk RNA-Seq Dataset Suggests Potential Mechanisms for Letrozole Resistance in Estrogen-Positive (ER+) Breast Cancer.

Estrogen receptor-positive (ER+) breast cancer is common among postmenopausal women and is frequently treated with Letrozole, which inhibits aromatase from synthesizing estrogen from androgens. Decreased estrogen slows the growth of tumors and can be an effective treatment. The increase in Letrozole resistance poses a unique problem for patients. To better understand the underlying molecular mechanism(s) of Letrozole resistance, we reanalyzed transcriptomic data by comparing individuals who responded to Letrozole therapy (responders) to those who were resistant to treatment (non-responders). We identified SOX11 and S100A9 as two significant differentially expressed genes (DEGs) between these patient cohorts, with "PLK1 signaling events" being the most significant signaling pathway. We also identified PRDX4 and E2F8 gene products as being the top mechanistic transcriptional markers for ER+ treatment resistance. Many of the significant DEGs that we identified play a known role in ER+ breast cancer or other types of cancer, which partially validate our results. Several of the gene products we identified are novel in the context of ER+ breast cancer. Many of the genes that we identified warrant further research to elucidate the more specific molecular mechanisms of Letrozole resistance in this patient population and could potentially be used as prognostic markers with further wet lab validation. We anticipate that these findings could contribute to improved detection and therapeutic outcomes in aromatase-resistant ER+ breast cancer patients.

A functional approach to defining and repairing moral injury: Evidence, change agents, clinical strategies, and lessons learned.

This is a conceptual overview of a premeeting institute (PMI) I presented at the 39th International Society for Traumatic Stress Studies (ISTSS) annual meeting in November 2023 entitled, "A Functional Approach to Repairing Moral Injury and Traumatic Loss in Context: Evidence, Change Agents, Clinical Strategies, and Lessons Learned." This paper was invited by the co-chairs of the Scientific Program Committee, Isaac Galatzer-Levy and Katharina Schultebraucks. I first describe the aims of the PMI and then summarize the foundational assumptions that led me to expand adaptive disclosure and create adaptive disclosure-enhanced (AD-E). The foundational assumptions are that (a) moral injury is a unique measurable potential clinical problem, (b) moral injury damages the sustaining building blocks to personal and collective humanity, and (c) repairing moral injury requires corrective humanizing and virtuous experiences and connections. I then provide an overview of AD-E and describe two new change agents- loving-kindness meditation and letter writing-that augment the original AD in service of promoting corrective experiences in the social world that are valued, valuing, and promote the experience of belonging.

An optimization framework for efficient and sustainable logistics operations via transportation mode optimization and shipment consolidation: A case study for GE Gas Power

General Electric (GE) Gas Power, a leading manufacturer of gas and steam turbines, manufactures and installs these turbines in power generation plants worldwide. They source components for these turbines from suppliers globally and transport these components to manufacturing and assembly locations in the United States using various modes of transportation, including ocean, air, and ground. These transportation options have different lead times and costs. The challenge lies in identifying the most cost-effective solution that meets the assembly requirements, given the high volume of shipments and the complexity of the intermodal freight network. To address this challenge, a customized, multi-period (dynamic), multi-commodity network flow model and a novel heuristic approach with a rolling time horizon are developed. This model incorporates consolidation and storage options at intermediate nodes, allowing the business to optimize its shipments. This research addresses a unique real-world logistics problem and offers an optimization model together with an efficient solution approach for industry. Computational experiments indicate that the heuristic approach proposed can yield results closely aligned with those produced by state-of-the art commercial solvers. Furthermore, the experiments show the criticality of full container load shipments in achieving substantial cost-saving in global shipments.

Antiwindup Compensation for Unstable Rigid-Body Systems with Quantized and Saturated Inputs

It is well known that actuator saturation can cause destabilization and degradation in performance; similar problems are encountered when actuation is quantized. This study proposes the design of an antiwindup compensator for systems with actuators that are limited to a finite number of quantization levels. This combination of discrete-level actuation and saturation poses a unique antiwindup problem that has not yet been solved. To surmount this combined issue, an antiwindup compensator is proposed, which provides ultimate boundedness of the system state within a prescribed region and guarantees that the state does not stray outside a larger compact set. The use of shifted ramp functions enables a less conservative bound on the control-signal error, which yields significantly lower L2 gain bounds compared to a standard sector-bound antiwindup design approach. A numerical simulation example illustrates the effectiveness on a rigid-body system, which inspired this study.

Post-truth conspiracism and the pseudo-public sphere

Rather than seeking to recuperate the ideal of a digital public sphere or lament its demise with the rise of social media platforms, in this paper I seek to identify the dangers of precisely this insistence to imagine the Internet as a public sphere. It is this curious insistence and persistence that, I claim, may feed into precisely those post-truth media dynamics such critical accounts worry about and rally against. The success of viral conspiracy narratives like Pizzagate and QAnon, as well as other forms of mis- and disinformation, hinges not (only) on the absence or distortion of a healthy democratic public sphere, as is typically assumed, but (also) on its persistence as an imaginary in an environment that obeys an altogether different set of logics, namely that of ‘communicative capitalism’ and ‘information warfare.’ Whereas the former has drawn most critical attention in connection to current post-truth dynamics (e.g., the effects of targeted advertising and the role of algorithms in creating polarizing echo chambers and filter bubbles), I will instead focus on the latter. The unique problem and ‘cunning’ of what I refer to as ‘post-truth conspiracism’ is that it draws on idea(l)s of digital publicness to establish its own epistemic legitimacy, as well as derive its unique powers of persuasion, while also mobilizing the full tactical arsenal of information warfare in a global attention economy. The resulting weaponization of digital public sphere imaginaries complicates attempts to recuperate the idea(l) of a digital public sphere as a solution to a ‘polluted’ information environment.

Research and Institutional Construction of Corporate Compliance Administrative and Criminals Involved in the Case

In the second half of the development of the compliance and rectification system for the companies involved in the case in my country, the poor connection between executions hindered the compliance and rectification system of the companies involved in the case from playing a greater practical role. The two main reasons for the dual illegality of the corporate administrative offenders involved and the independence of our country's execution agencies make the connection of executions a unique practical problem in China. In the illegal investigation, case filing, investigation and prosecution, as well as the compliance extension stage after the end of the criminal process, there are institutional gaps in the connection between executions. Existing problems can be solved one by one by promoting execution agencies to strengthen exchanges and cooperation in the stages of illegal investigation, reconnaissance, review and prosecution, mutual recognition of compliance results, relay compliance rectification, optimizing third-party mechanisms and attaching importance to big data empowerment.

Метод генерации уникальных вариантов для математических задач

The article poses the problem of creating generators for unique multivariate mathematical problems. Types of methods of obtaining random numbers are considered. A comparative analysis of the standard generator used by developers with the generator providing the possibility to create sets of numbers occurring once among the required range of values is carried out. A specific example is provided that requires the application of unique problem sets and parameters. The examples are accompanied by formulas in general form, listings of the proposed algorithms of functions in JavaScript, a brief verbal description of the result of the functions. Attention is paid to the generation of numbers without zero, to the peculiarities of development, taking into account the choice of the best interval for a wide range of values of generated numbers, excluding the use of loops and reducing risks. The article explains a method of description of the result of generation of numbers in JSON format, which can be used when transferring the obtained sets between different programming languages.

Метод генерации уникальных вариантов для математических задач

The article poses the problem of creating generators for unique multivariate mathematical problems. Types of methods of obtaining random numbers are considered. A comparative analysis of the standard generator used by developers with the generator providing the possibility to create sets of numbers occurring once among the required range of values is carried out. A specific example is provided that requires the application of unique problem sets and parameters. The examples are accompanied by formulas in general form, listings of the proposed algorithms of functions in JavaScript, a brief verbal description of the result of the functions. Attention is paid to the generation of numbers without zero, to the peculiarities of development, taking into account the choice of the best interval for a wide range of values of generated numbers, excluding the use of loops and reducing risks. The article explains a method of description of the result of generation of numbers in JSON format, which can be used when transferring the obtained sets between different programming languages.

Why data about people are so hard to govern

AbstractHow data on individuals are gathered, analyzed, and stored remains largely ungoverned at both domestic and global levels. We address the unique governance problem posed by digital data to provide a framework for understanding why data governance remains elusive. Data are easily transferable and replicable, making them a useful tool. But this characteristic creates massive governance problems for all of us who want to have some agency and choice over how (or if) our data are collected and used. Moreover, data are co‐created: individuals are the object from which data are culled by an interested party. Yet, any data point has a marginal value of close to zero and thus individuals have little bargaining power when it comes to negotiating with data collectors. Relatedly, data follow the rule of winner take all—the parties that have the most can leverage that data for greater accuracy and utility, leading to natural oligopolies. Finally, data's value lies in combination with proprietary algorithms that analyze and predict the patterns. Given these characteristics, private governance solutions are ineffective. Public solutions will also likely be insufficient. The imbalance in market power between platforms that collect data and individuals will be reproduced in the political sphere. We conclude that some form of collective data governance is required. We examine the challenges to the data governance by looking a public effort, the EU's General Data Protection Regulation, a private effort, Apple's “privacy nutrition labels” in their App Store, and a collective effort, the First Nations Information Governance Centre in Canada.

IJCM_187A: Prevalence and risk factors of childhood obesity among school-going children in a metropolitan city of india.

Background: Childhood obesity is a grave public health concern in the 21st century. It is becoming a widespread problem in low and middle-income countries, particularly in urban areas. Childhood obesity is a precursor to metabolic syndrome, poor physical health, mental disorders, respiratory problems, and glucose intolerance, which can all continue into adulthood. Developing countries like India face a unique problem of a ‘double burden’, where undernutrition and obesity co-exist. Objectives: The study aimed to determine the prevalence of overweight/ obesity among school-going children and to identify the modifiable risk factors associated with it. Methodology: An epidemiological cross-sectional study was conducted in a private school located in the Western suburbs of Mumbai. The study included all students from the 1st to 10th standard of the secondary section, who were willing to participate. Before the study, necessary permissions were obtained from the school authorities and parental consent was taken. The study was conducted over 4 days in October 2023. Data was collected through interviews using a pre-structured questionnaire. The collected data will be analyzed using SPSS for descriptive and inferential statistics. Results: Among 521 participants, the Prevalence of Overweight is 14.77% and Obesity is 6.71% in our study. Statistical significance was found between BMI and Smartphone usage, BMI and Occupation of Mother. Conclusion: Dietary factors have always been associated with overweight & obesity however our study reveals that other factors also play a pivotal role in development of obesity which is an important risk factor for Non- Communicable Diseases further in adulthood.

Scrub Typhus During Pregnancy: A Study from Northeast India

Introduction: Scrub typhus is a crucial underrecognized cause of undifferentiated febrile illness in Northeastern India. Scrub typhus in pregnancy is an uncommon entity. In such cases, not initiating effective and safe antibiotics leads to maternal and fetal complications. To reduce complications, it is a must to keep a high index of clinical suspicion. Methodology: The present study was conducted to find the various disease manifestations of scrub typhus during pregnancy from January 2014 to December 2018. It was a retrospective study that included hospitalized patients with a diagnosis of scrub typhus during pregnancy. The scrub typhus was diagnosed based on the clinical presentation and serological test with Weil-Felix test titer for OXK more or equal to 1:160 or immunochromatographic test positive for scrub typhus IgM antibody. Result: During the study period, complete data were obtained from nine patients. The mean age of the patient was 26.5 years. A maximum of five patients presented in the third trimester, and two presented each in the first and second trimesters. Adverse fetal outcome was found in 33.3% of cases. Two patients had multiorgan dysfunction syndrome, and hepatitis was found to be a common occurrence. Conclusion: Scrub typhus during pregnancy presents a unique problem that is associated with high fetal loss and maternal complications. Keeping a high index of suspicion for diagnosis in endemic regions is essential, as prompt initiation of safe and effective antibiotics can prevent complications.

Isolated lateral-sided knee pain in total knee arthroplasty. A review.

Isolated lateral-sided knee pain is a unique problem following total knee arthroplasty (TKA). Reported causes include soft tissue impingement against extruded cement, an overhanging tibial tray, remnant osteophytes rubbing against the iliotibial band (ITB), popliteal tendon impingement, fabella syndrome, and synovial tissue impingement in the lateral gutter. In addition, iliotibial band traction syndrome secondary to guided motion Bi-cruciate stabilizing knee arthroplasty has been recognized as a new clinical entity. Initial work up should include ruling out the most common causes of painful TKA including infection, aseptic loosening, and instability. Radiographs and CT scan are utilized to identify potential source of pain. Ultrasound evaluation (with elicited probe tenderness) can increase diagnostic accuracy. Ultrasound guided local anesthetic injections can confirm the source of pain. Anti-inflammatory medications, physical therapy with ITB stretches, and therapeutic local steroid injections are initial treatment modalities. Satisfactory resolution of symptoms may require surgical intervention directed at the specific cause and may avoid the morbidity associated with revision TKA.