Delta Electronics (China)

Significant technological advancements have been made towards high-density high-frequency power conversion using Gallium Nitride (GaN) devices. As such, it is possible to shrink the size of passive components such as magnetics and capacitors resulting in compact designs. Nonetheless, high switching frequency leads to stronger conducted emissions occurring at higher end of the frequency spectrum necessitating use of additional passive filtering to meet emissions standards. Ultimately, this defeats the purpose of pushing towards high switching frequency. This paper presents a unique integrated Electromagnetic Interference (EMI) filter solution for typical isolated high-voltage DC-DC resonant converters. Three design methods on magnetics design, layout and software/control techniques are proposed. These concepts are implemented on planar Printed Circuit Board (PCB) based 6.6 kW CLLLC resonant converter. The proposed methods do not require any external DC filters and can minimize EMI filter volume requirement in a typical OBC or Power Supply Unit (PSU) application. Furthermore, these solutions can be extended to LLC, CLLC, Series Resonant Converter (SRC) type topologies, both single and three-phase as well.

BackgroundThe Sun procedure has been widely adopted across China for the treatment of acute type A aortic dissection (ATAAD). Although favorable outcomes have been reported from high-volume centers, institutional series offering detailed early data using modern operative protocols remain limited. This study is structured in two parts: first, a review of the literature on the development and reported outcomes of the Sun procedure in different aortic populations across China; and second a presentation of contemporary operative characteristics and early outcomes in patients undergoing the Sun procedure for ATAAD at a single institution.MethodsA retrospective analysis was conducted on 729 consecutive patients with ATAAD treated at DeltaHealth Hospital from 2016 to 2024. Among these, 573 patients (78.6%) underwent total arch replacement with frozen elephant trunk (FET) using the Sun procedure. Baseline characteristics, operative variables, and early outcomes were analyzed. Neurologic, renal, pulmonary, and systemic complications are reported.ResultsThe mean age of patients was 52.7±14.1 years, and 73.5% were male. Cardiac tamponade was present in 19.1% of patients at presentation. The history of cerebrovascular disease was noted in 4.1%, 3.4% had chronic kidney disease and 13.6% had Marfan syndrome. In-hospital mortality was 4.1%. Major complications included stroke (10.2%), spinal cord injury (SCI) (2.6%), acute renal failure (8.4%), gastrointestinal complications (4.1%), and reoperation for bleeding (14.3%). Sternal dehiscence and limb ischemia occurred in 1.8% and 1.6% of patients, respectively. Outcomes were achieved despite the presence of significant preoperative malperfusion syndromes, cerebral (8.2%), coronary (13.6%), and spinal cord malperfusion (2.2%).ConclusionsThe Chinese experience with the Sun procedure highlights the potential of standardized surgical strategies in complex aortic disease. This dataset affirms the technique’s safety, durability, and adaptability across acute, chronic, and heritable aortic pathologies.

This study investigates the relationship between indoor air flow and accumulation of polycyclic aromatic hydrocarbons (PAHs) using spider silk as a passive sample Through a combination of computational fluid dynamics (CFD) simulations and experimental data, research di a significant difference under effective spider silk in controlled indoor air quality (IAQ). The study reveals significant variations in PAH accumulation within spider webs across different indoor environments, with stagnant airflow areas exhibiting higher PAH concentrations. Specific locations, such as corners and ventilation outlets, show consistent trends in PAH accumulation, underscoring the importance of strategic spider web placement for effective passive sampling. The research also highlights intriguing disparities in silk production among spider species and selective accumulation of different PAHs. The findings contribute to a nuanced understanding of indoor environmental dynamics and bio-monitoring outcomes, emphasizing the utility of spider silk as a reflective bio-monitor for assessing IAQ. This study provides valuable insights for future research endeavors aiming to enhance our understanding of indoor environmental quality and optimize passive sampling strategies.

This study examined the influence of human resources policies on employees’ attitudes using the Federal University of Petroleum Resources, Effurun, Delta State as a case study. The study used the survey research design and the instrument of data collection was the questionnaire which was administered to two hundred (200) academic and non-academic staff of the Federal University of Petroleum Resources. Data obtained in the survey were analyzed using linear regression technique. It was found that human resource recruitment and selection policy had a significant influence on employees’ attitudes (F-value = 3.246; P-value = 0.003). In addition, we found that human resource staff training and development policy had a significant effect on employees’ attitudes (F-value = 5.017; P-value = 0.026). The study recommends that the management of Nigerian public institutions of higher learning should sustain and improve on their recruitment and selection and staff training and development policies in order to enhance employees’ attitude to work. More so, there is a need for the management of Nigerian public institutions of higher learning to embrace diverse types of human resource policies that will improve employees’ attitudes to work.

The study's goal is to assess students who are enrolled in postsecondary mathematics in terms of their achievement and mathematical reasoning skills. Most experts think that for students to study mathematics, they must possess the ability to reason since solving problems in mathematics demands it. The achievement has a bearing on this since it is important for the school and the instructors to be aware of the academic performance of the pupils in various subject areas to track their progress. A student's accomplishments aid the instructor in determining their rank. The idea that mathematics is the most difficult subject has made learning the subject quite challenging. The ability of mathematics to reason is one significant component of mathematics that many overlook. Mathematical reasoning is crucial for success in the sciences, humanities, and other fields that rely on it. The current study examined math achievement and thinking skills. 228 students served as the study sample for this investigation. The design is expo facto. To direct the study, two research questions were established. According to the study, students' achievement is influenced by mathematical thinking. Additionally, female students outperform male students in math and courses closely related to mathematics.

Lately Silicon Carbide (SiC) and Galium Nitride (GaN) based high frequency power conversion has gained immense popularity which stems from relatively low switching energy, robustness to high temperature operation, wide-band gap and superior thermal limits. While this aspect inherently results in a high-density power stage design, the design of adjoining passive components, particularly magnetics, needs careful attention. This is especially true if the compatibility of core and winding options and their performance is limited with the use of higher switching frequency. In this regard, this paper presents a brief review of existent research conducted in materials, optimization and integration of magnetics for single and three phase applications, ranging from filters, resonant inductors to isolation transformers. Design knobs pertaining to medium voltage (MV) applications, low-voltage (LV) applications, e-mobility sector such as more electric aircrafts (MEAs) and electric vehicles (EVs) are discussed. Guidelines for magnetics design are summarized for each application with a projected roadmap on future trend for magnetics.

<div class="section abstract"><div class="htmlview paragraph">Electronic control units of Bendix® ABS/ESC and Collision Mitigation Systems have the capability to record event data in the ABS/ESC control unit. Bendix refers to this event data recording functionality as the Bendix Data Recorder (BDR). This paper presents an overview of the BDR functionality and examines the range and resolution of data elements, the synchronicity or timing of the recorded data, and application of the data for use in analyzing crashes. Various tests were performed using trucks equipped with Bendix® Wingman® Fusion™ and were conducted in a manner to trigger BDR records. BDR data was compared to data collected from the J1939 CAN Bus and from Racelogic VBOX data loggers.</div></div>