bluuebunny/crossref_metadata_2025 huggingface dataset:
Combined Use of Copernic RC Venous Remodeling Balloon and Aspiration Thrombectomy for Cerebral Venous Sinus Thrombosis
Authors: Dhok Swapnil M. , Gudipati Ananta R. , Kaul Subhash , Yada Praveen , Babu P Suresh
Published: January 2024

Cerebral venous sinus thrombosis is a potentially fatal condition. The current first line of treatment for sinus thrombosis is anticoagulation. Endovascular treatment is an alternative for patients whose symptoms progress despite adequate medical management. Mechanical thrombectomy is required in the setting of a large clot burden. Unfortunately, the conventional technique of intraarterial thrombectomy with the use of a stent retriever and/or aspiration is not very effective in sinus thrombosis because of a larger clot burden compared to an intracranial artery. Herein we describe our endovascular approach of mechanical thrombectomy in sinus thrombosis using Copernic 8 × 80 RC (Rene Chapot) balloon and aspiration catheter.
Intracranial Carotid Artery Calcification Subtype in Patients with Anterior Circulation Acute Ischemic Stroke Undergoing Intravenous Thrombolysis
Authors: Zhu Jie , Liu Qiping , Zhuang Yuzhong , Wei Ran , Sun Yi , Wang Hao , Song Bin
Published: January 2024

Background and Aim:

The aim of this study was to investigate the potential value of intracranial carotid artery calcification (ICAC) in therapeutic efficacy and functional outcomes in patients with anterior circulation acute ischemic stroke (AIS) undergoing intravenous thrombolysis.

Materials and Methods:

A total of 207 patients with anterior circulation AIS who underwent intravenous thrombolysis were enrolled in this retrospective study. We divided them into three groups according to thin-slice head noncontrast computed tomography as follows: no ICAC, medial ICAC, and intimal ICAC. The differences in risk factors of different ICAC subtypes were compared, and the effect of ICAC subtype on hemorrhage transformation (HT) after intravenous thrombolysis was also evaluated. Functional outcomes were assessed at 90 days using the modified Rankin Scale.

Results:

Compared to the no and intimal ICAC, patients with the medial ICAC were older and more likely to have diabetes mellitus, hyperlipidemia, previous stroke, and atrial fibrillation. Moreover, the medial ICAC group had a high baseline National Institute of Health Stroke Scale (NIHSS) score and a high incidence of HT. Multivariate logistic regression analysis showed that baseline NIHSS score (odds ratio [OR]: 1.121, 95% confidence interval [CI]: 1.027–1.224) was independently associated with HT. Medial ICAC (OR: 7.418, 95% CI: 1.190–46.231) and baseline NIHSS score (OR: 1.141, 95% CI: 1.042–1.250) were independent risk factors of poor functional outcome at 90 days.

Conclusions:

Medial ICAC could be a new imaging biomarker for predicting functional outcomes in patients with anterior circulation AIS undergoing intravenous thrombolysis. Medial ICAC and baseline NIHSS score were independently associated with poor prognosis at 90 days.
Dimensional Stability and Retention Strength of Impressions to Custom Impression Trays Fabricated Using Conventional Method and Additive Technology - An In-vitro Study
Authors: Priyadarshini K Sangeetha , Nandini V Vidyashree , Marimuthu Russia , Lathief Jailance
Published: January 2024

Background:

3D printing technology is replacing manual fabrication in all fields. 3D-printed impression trays should be assessed as they could replace conventional impression trays in the future.

Aim:

In-vitro comparison and evaluation of the dimensional stability and retention strength of impressions to custom impression trays fabricated using conventional method and additive technology.

Materials and Methods:

A maxillary edentulous auto-polymerizing acrylic resin model served as the master model. Two moulds were prepared from the master model in order to obtain 12 casts. One cast was scanned for 3D printing digital light processing (DLP) and fused deposition modelling (FDM) 24 impression trays using polylactic acid (PLA). Twelve casts were used to fabricate light cure impression trays. Polyvinyl-siloxane impressions were made on the master model using 36 impression trays and 18 trays each were used to assess dimensional stability and retention strength.

Results:

In dimensional stability analysis, one sample t-test revealed a statistically significant difference between each group and the master model followed by a one-way ANOVA. There were significant differences, but the difference was less with FDM trays (P < 0.05). In retention strength analysis, one-way Analysis of variance (ANOVA) revealed statistically significant difference between each group and post-hoc test revealed specific difference, the highest with FDM trays (P < 0.05).

Conclusion:

Dimensional changes were observed at 30 minutes and 72 hours. Lesser dimensional changes were observed when impressions were made using FDM trays followed by DLP and light cure trays. The mean retention strength seen in descending order was FDM, followed by DLP and light cure trays. The best retention strength was noticed when impressions were made using FDM trays.
Relationship and Accuracy of Urine Lead as an Alternative to Blood Lead Biomarker among Panel Beaters in Enugu Metropolis: Nigeria
Authors: Kassy Chukwukasi Wilson
Published: December 2023

Background and Aims:

The limited alternatives to blood lead biomarkers continue to affect the control of occupational lead exposures. This study assessed the relationship and accuracy of urine lead biomarker as an alternative to blood lead biomarker among roadside and organized panel beaters in Enugu metropolis, Nigeria.

Methods:

This was a cross-sectional analytical study of 428 panel beaters in Enugu metropolis. Samples collected were analyzed using Atomic Absorption Spectrometer (AAS) at 283.3 nm wavelengths. Data were analyzed using correlation and receiver operating characteristics (ROC).

Result:

A linear positive relationship with high accuracy and sensitivity were found between blood and urine biomarkers.

Conclusion:

Urine biomarker has a linear relationship with blood biomarker and showed a significant accuracy for the measurement of occupational lead exposure. Therefore, a urinary biomarker can serve as an alternative replacement to blood lead in occupational health practice.
Perceived Difference in Handling Stress and Self-Care Strategies at Workplace among Public Sector Employees of Land Resources Development Department
Authors: Kumar CTL Kiran , Krishnamurthy Latha , Meena Kolar Sridara Murthy , Kapanee Aruna Rose Mary , Pravitha M R , Dasgupta Madhuporna
Published: December 2023

The perception of the employees on handling stress at workplace and effectiveness of stress management programs varies due to multiple internal and external factors. Thus, the present study aims to measure the perceived level of difference in psychosocial stress at workplace following a stress management program. This was an interventional study conducted among 30 public sector employees working in Land Resources Development Department. The study tools used were K10, World Health Organization Quality of Life Scale (WHOQOL-BREF), and a work-life balance questionnaire which were quantitatively analyzed using paired t-test, and also, thematic analysis was used to assess the effectiveness of the stress management program. Stress management abilities improved on the work-life balance questionnaire with a P value of 0.027 after the intervention and a significant difference in the environment domain with a P value of 0.041 was found on WHOQOL-BREF. Thematic analysis showed a perceived reduction in negative reactions to work stress and improvement in self-care strategies after the intervention. This study highlights the subjective experience of work stress and stress management abilities that need to be addressed through the effective collaborative model of a stress management program.
Radiological Anatomy of Eustachian Tube and its Correlation with Graft Uptake in Type I Tympanoplasty
Authors: Sethi Nandini , Sharma Rohit , Sharma Vinit Kumar , Prajapati Neeraj , Rana Amit Kumar
Published: December 2023

Introduction:

Eustachian tube (ET) also known as pharyngotympanic tube connects nasopharynx with the middle ear. Evaluation of ET anatomy is aimed in patients with chronic otitis media.

Materials and Methods:

In a study of 53 patients, HRCT Temporal bone was done on 128 dual source simens somatom definition flash machine on 5mm cut section and tympanoplasty was carried out.

Results:

ET angle is one of the important factors for middle ear aeration. Outcome of tympanoplasty at 12th week was 88.7%. In the patients with vertical Eustachian Tube (i.e., more Eustachian Tube angle with the horizontal plane), better graft uptake in tympanoplasty was observed which was statistically significant. However, graft uptake did not correlate with the length of the Eustachian tube.

Conclusion:

It was concluded that on measuring ET length on HRCT, majority of the patients had bony length of 10-12 mm, cartilaginous length of 15-19 mm and total ET length of 28-32 mm. Majority of the patients had ET angle of 21-30 degrees with the hard palate.
Studying the Effect of Maternal Anemia and Neonatal Hematological Indices on Auditory Brainstem Responses of Newborn Babies
Authors: Deepashree Somanahalli Ramachandra , Uppunda Ajith Kumar , Suryanarayana Kumar Gavali
Published: December 2023

Purpose:

Animal studies have shown the effect of maternal anemia (MA) and neonatal iron deficiency (ID) on the auditory system of young ones. However, the evidence supporting the same in human infants is inconclusive. Hence, the present study aims to investigate the effect of MA and neonatal iron status on the auditory brainstem responses (ABRs) of newborn babies.

Materials and Methods:

A total of 100 babies (gestational age ≥34 weeks) were divided into “Normal” group-57 babies without MA, “Mild” group-22 mild MA babies, and “Moderate” group-21 moderate MA babies. The ABR was recorded using 80 dBnHL click stimuli at 10 and 90 Hz repetition rates.

Results:

The results based on MA showed a significantly better presence of ABR peaks for the normal group than mild and moderate groups at a higher rate and no significant difference for latency and amplitude measures across the groups. The results based on neonatal hematological indices showed that the ABR measures were better in babies with probable ID which could be attributed to neural hyperactivity and an increase in axonal diameter leading to faster nerve conduction velocity.

Conclusion:

The auditory system maturation in newborn babies is influenced by maternal as well as neonatal iron status.
Combined fractional carbon dioxide laser with long pulsed Nd:YAG laser for treatment of immature hypertrophic scar
Authors: Keshk Zaynab S. , Salah Manal M. , Samy Neiven A.
Published: January 2024

Background

Immature hypertrophic scar complicated with contracture, disability, disfigurement, social embarrassment, pain, itching, residual scar, and prolonged maturation period. Various treatments for immature hypertrophic scar are used with limitations for each treatment.

Objective

To evaluate the efficacy and safety of combined fractional carbon dioxide (CO2) and Neodymium-doped Yttrium Aluminum Garnet (Nd:YAG) lasers for the treatment of immature hypertrophic scar both clinically and histopathologically.

Patients and methods

Total of 30 patients with single or multiple immature hypertrophic scars. The single scar was not less than 14 cm in length. In the same patient, single or multiple scars were divided randomly into treated areas and control areas. The treated areas were submitted to 5 sessions of fractional CO2 laser combined with long pulsed Nd:YAG laser, one month in between sessions, the control areas did not receive any treatment. Vancouver Scar Scale (VSS) and patient and observer scar assessment scale (POSAS) were used for clinical evaluation before, 3, and 6 months after treatment. Collagen area percent, elastin area percent, and epidermal thickness were assessed histopathologically before and 3 months after treatment.

Results

The scar areas treated with combined fractional CO2 laser and long pulsed Nd:YAG laser showed superior significant clinical improvement with VSS and POSAS than areas did not receive any treatment (except for the pigmentation parameter of both VSS and POSAS), especially 6 months after last treatment without significant side effects for laser therapy. Opinions of the patients showed superior significant improvement in laser treated areas than areas did not receive any treatment. Epidermal thickness, collagen area percent and elastin area percent showed superior significant improvement in laser treated areas than areas did not receive any treatments three months after last laser session.

Conclusion

Combined treatment of immature hypertrophic scar with fractional CO2 and Nd:YAG lasers is effective, tolerable, and safe.
Granulomatous dermatitis post Mycobacterium Indicus Pranii (MIP) vaccine in severe covid-19 infection: an exaggerated hypersensitivity phenomenon
Authors: Agarwal Pooja , Chaudhary Raju , Baxi Kalgi , Shah Malhar
Published: January 2024

Mycobacterium indicus pranii (MIP) vaccine is widely used in dermatology as immunotherapy for warts as well as in patients with leprosy. During the COVID-19 pandemic, a positive role of MIP as an immunomodulator in SARS-CoV-2 disease was reported after pilot research, with minor adverse effects. We report a case of a 65-year-old male, presenting with skin lesions suggestive of noninfective granulomatous dermatitis for 4 months, at the sites of MIP intradermal injections, allegedly received during a hospital stay for severe COVID-19 disease. The patient presented with nonhealing nodulo-ulcerative lesions at the sites of injection, which persisted for 4 months associated with intermittent serous discharge and showed no signs of healing despite supportive treatment. The patient was started on a combination therapy of ofloxacin 400 mg /day and clarithromycin 500 mg 12 hourly for 2 months. At the end of 2 months, all the lesions showed complete healing with a resolution of discharge and nodularity, leaving behind postinflammatory hypopigmentation and atrophic scarring. The patient was followed up for 4 months after stopping treatment during which time he had no relapse of the lesions. This case has been reported to the India Pharmacopoeia.
Periosteal Manifestations of Osteomyelitis and Arthritis on Ultrasound: A Systematic Review
Authors: Waitayangkoon Palapun , Weilg-Espejo Pablo , Kissin Eugene Y.
Published: January 2024

Ultrasound (US) can visualize the periosteal changes in the early stage compared to radiography. In this review, we studied periosteal manifestations on US and assessed their diagnostic utility for osteomyelitis (OM) and arthritis. We included articles that studied ultrasonographic findings of periosteal changes in OM and arthropathies with aims to systematically review periosteal manifestations of each condition and summarize diagnostic values of each finding. A total of 13 articles were included in the systematic review. Of these, 10 articles are on OM, 3 articles are on psoriatic arthritis (PsA), 1 article is on rheumatoid arthritis (RA), and 1 article is on gouty arthritis (GA). In OM, subperiosteal fluid/subperiosteal collection (SF/SC) was detected in 32%–76% within 72 h after presentation. Periosteal reaction (PR) was seen after day 4 and the sensitivity on US ranges from 33% to 100%. In PsA, PR was seen near 16%–59% in active PsA joints. Periosteal changes are rarely detected in RA joints. Small hyperechoic spots were seen in 87.5% of GA. SF/SC may be seen on US as the earliest sign followed by PR for OM. PR is more specific in PsA than RA. Further investigations on periosteal abnormalities on US are warranted to confirm our findings.
Assessment of self-directed learning in the competency-based medical education
Authors: Shrivastava Saurabh RamBihariLal , Shrivastava Prateek Saurabh
Published: January 2024

Self-directed learning (SDL) has been acknowledged as a crucial approach in the delivery of medical education. In fact, the goal of lifelong learner defined for a medical graduate cannot be accomplished if the student does not practice SDL. Realizing the importance of SDL in the field of medical education, in the recently adopted competency-based undergraduate curriculum, the regulatory body has clearly specified defined number of hours per year per subject to ensure that provision is created in the curriculum and all the planning is done keeping that in mind. However, the real challenge in the implementation has been the assessment of the SDL, as conventional tools cannot be employed for the same. In general, four different types of assessment methods can be employed, namely, self-assessment, peer assessment, teacher assessment, and external assessment. In conclusion, assessment of SDL sessions is a potential challenge for all the teachers; nevertheless, the adoption of a well-thought approach will surely reduce the apprehensions associated with it and eventually enhance the learning among of the medical students.
Mesenteric fibromatosis
Authors: Pore Anant , Pore Sayali , Bang Ravi , Ikhar Sushantkumar , Ronghe Chetan
Published: January 2024

A 28-year-old patient reported having a lump in the right lower abdominal and pelvic area for the last 21 days, along with pain, anorexia, fever, and nausea. After a thorough investigation, an antero-posterior (AP) scanogram of the patient showed a clearly defined lump in this area. Histopathological examination showed mesenteric fibromatosis. Resection and anastomosis were done. Our case is one of the few known cases of the extremely rare condition fibromatosis of the mesentery. These tumors present a diagnostic and therapeutic difficulty due to their rarity. These tumors are still asymptomatic; however, they frequently appear as an asymptomatic mass. There are not any obvious therapy options. The preferred method of treatment is surgical excision with a wide margin; we underwent the same technique and the prognosis was good. Numerous single case reports with various and peculiar appearances and their difficulties exist. This case report aims to offer the current understanding of mesenteric fibromatosis as well as our clinical experience with the presented patient. Following surgery, the patient did well, and a 3-month follow-up revealed a typical recovery.
Anterior segment optical coherence tomography findings in epibulbar choristomas
Authors: Gonzalez-Hernandez Martha , Martinez-Solis Fernando , Paz-Gonzalez Miguel , Garza-Leon Manuel
Published: January 2024

Epibulbar choristomas are benign congenital ocular tumors characterized by abnormal growth in the epibulbar tissue, eyelids, and choroids. Two cases of epibulbar choristomas are described; the first one is a 39-year-old woman who presented a temporally conjunctival mass that had progressed in size accompanied by foreign body sensation and epiphora. Optical coherence tomography (OCT) and surgical resection were performed with a histopathological diagnosis of dermolipoma. The second case is a 7-year-old boy with a congenital corneal lesion in the nasal sector, elevated, vascularized, and with decreased visual acuity. In both cases, OCT showed a thinned epithelium with hyporeflective subepithelial fusiform lesions. OCT is an auxiliary method for the diagnosis of conjunctival lesions, such as epibulbar choristomas.
Maternally inherited diabetes and deafness macular dystrophy
Authors: Miranda Vitor , Aguiar Catarina , Chibante-Pedro Jão , Ruão Miguel
Published: January 2024

The m.3243A>G variant in the MTL1 gene is a DNA point mutation which has been shown to cause a variety of diseases including retinal abnormalities. We report on the ophthalmologic phenotype and systemic findings in a new patient with this mutation, presenting with sensorineural hearing loss, diabetes and macular dystrophy. We characterized the retinal phenotype with a multimodal approach and throughout the follow-up period we observed sustained centripetal progression of the areas of chorioretinal atrophy.
Impact of a Virtual Game, ‘Name That Band,’ on Older People’s and PharmD Students’ Feelings of Social Isolation During COVID-19
Authors: Weygint Alison M. , Whittington Brooke T. , Lee Jeannie K. , Campbell Ashley M.
Published: December 2023

Background Prior to the COVID-19 pandemic, PharmD students at the University of Arizona (UArizona) had a long-standing relationship with the older people at St. Luke’s Home, a local Eden Alternative assisted-living community. Hosting community engagement programs for
assisted-living residents was challenging with COVID-19 precautions and older individuals suffering from social isolation and loneliness. Objective To determine the impact of playing a virtual game, ’Name That Band,’ on older people's and PharmD students’
feelings of social isolation during the COVID-19 pandemic. Methods Questionnaires were administered before and after a virtual game to residents at St. Luke’s Home and PharmD students at UArizona. Participants were asked about their mood before COVID-19 and pre-and
postgame, as well as their social interactions and feelings of loneliness using the Modified UCLA Three-Item Loneliness Scale, which assesses a composite score of lack of companionship, feelings of being left out, and isolation. Results Fifteen older people and 11 students
participated in the game (N = 26). All participants completed the pregame survey and 25 completed the postgame survey. The older people reported fewer feelings of isolation and loneliness (measured by a reduction in UCLA Loneliness Scale score) postgame compared with pregame. The students
reported a higher total UCLA Loneliness Scale score during the pandemic than prepandemic, but there was no difference in their scores postgame compared with pregame. More older people and students reported feeling ‘happy’ after playing the virtual game together compared with before
the pandemic and before playing. The aspect of the activity that helped older people and students feel more socially engaged was playing a game. Conclusion A social intervention using a virtual game may be a tool that can be used to decrease feelings of isolation and increase
engagement for older people residing in an assisted-living community.
Real-World Analysis of Long-Acting and NPH-Containing Insulins on Glycemic Control
Authors: Hale Genevieve , Marcellus Valerie , Benny Tina , Moreau Cynthia , Rosario Elaina , Perez Alexandra
Published: December 2023

Introduction Affordability of insulin products has become a concern in the past several years as the average price of various insulin products has increased. While awaiting legislation at the federal level that would address issues leading to high insulin costs, providers
may have shifted prescribing practices to prescribe the lowest-priced insulin products to achieve patients’ treatment goals. Objective To compare the prevalence of hypoglycemic events between patients receiving lower-cost neutral protamine Hagedorn (NPH)-containing
human insulins and higher-cost long-acting insulin analogs in Medicare Part D enrollees within a management services organization, as well as assessing glycemic control and changes in body mass index. Methods This was a multicenter, retrospective study conducted at three
primary care clinics. The co-primary outcomes were percent difference of documented mild and severe hypoglycemic events between individuals receiving NPH-containing human insulin and long-acting insulin. Results A total of 72 patients met inclusion criteria and were receiving
NPH-containing human insulins or the long-acting insulin analogs, 15 and 57 patients, respectively. Severe hypoglycemic events occurred in 3.5% vs 0% of the long-acting insulin analog and NPH-containing human insulin group, respectively (P = 0.999). Mild hypoglycemic episodes were experienced
by 31.6% versus 33.3% of long-acting insulin analog and NPH, respectively (P = 0.539). For secondary outcomes, no difference was observed in glycemic control outcomes across insulin groups. Conclusion Among Medicare Part D patients with type 2 diabetes mellitus,
the use of NPH-containing human insulins was not associated with an increased risk of mild or severe hypoglycemia-related episodes or reduced glycemic control compared with long-acting insulin. Study findings suggest that lower-cost, NPH-containing human insulins may be an alternative to higher-cost,
long-acting insulin analogs.
An Energy-Efficient Merge-Aware Cruise Control Method for Connected
Electric Vehicles
Authors: Vellamattathil Baby Tinu , HomChaudhuri Baisravan
Published: January 2024

This article presents a merge-aware cruise control method that incorporates
vehicle-to-vehicle (V2V) information and aims at improving the energy efficiency
of vehicles and reducing speed disruptions of merging traffic during highway
merges. During the events of highway merges, the gap between the ego and the
preceding vehicle reduces drastically, which can result in sudden braking of the
ego vehicle and thus reduction of its energy efficiency. We propose a rather
simple cruise control algorithm to eliminate such sudden variations in the gap
and velocity with respect to the preceding vehicle during highway merges, thus
reducing the large accelerations and braking during such events and thereby
improving energy efficiency. The proposed algorithm incorporates future traffic
information and has computational requirements similar to adaptive cruise
control methods, hence it is real-time applicable. Data used in this article are
taken from on-road experiments using a 2020 Tesla Model 3. Simulation results
show the efficacy of our proposed control algorithm.
Research on the Vibration Reduction Effect of Variable Damping and
Stiffness Electromagnetic Damper
Authors: Zhan Haoyu , Liu Pengfei , Ning Donghong , Yu Jianqiang , Du Haiping
Published: December 2023

This paper studies and compares the vibration control performance of variable
damping electromagnetic damper (VD-EMD) and variable stiffness and damping
electromagnetic damper (VSD-EMD), and explores the advantages of VSD-EMD over
VD-EMD in terms of controllability and improvement of ride comfort. In VD-EMD, a
variable resistor is connected to the DC motor, the equivalent damping is
related to resistance but not to frequency, by adjusting the resistance of the
variable resistor, the damping of VD-EMD can be changed. In variable stiffness
electromagnetic damper (VS-EMD), a branch formed by connecting a variable
resistor and an inductor in series is connected to the DC motor, by adjusting
the variable resistor, the equivalent stiffness of VS-EMD can be controlled, in
addition, the equivalent stiffness also varies with the excitation frequency.
The mechanical characteristics of VD-EMD and VS-EMD have been verified. Since
shock absorber with multiple variable mechanical characteristics can achieve
better vibration reduction effects, the variable stiffness and damping functions
of VSD-EMD has been achieved by paralleling the circuits of VD-EMD and VS-EMD.
To compare the vibration control effects of VD-EMD and VSD-EMD, they are applied
to a quarter car model. A sliding mode controller is designed and two
semi-active control strategies are applied to control the vibration of vehicles
by VD-EMD and VSD-EMD respectively. Under sinusoidal excitation, the
effectiveness of the control strategies is verified and the peak acceleration of
the sprung mass of VSD-EMD has decreased. In addition, the output force of
VSD-EMD has a longer tracking time for the ideal force which means that VSD-EMD
has higher controllability. Under random road excitation, VSD-EMD has better
vibration reduction effects in the frequency range of 0.1-2.5, 7.5-10, and above
22 Hz. In addition, the root-mean-square of VSD-EMD’s sprung mass decreased by
12.9% compared to VD-EMD. Electromagnetic damper with variable damping and
stiffness functions can broaden the vibration reduction range and achieve a
better vibration reduction effect.
Adaptive Harmonic Extended State Observer Based Anti-Swing Attitude
Control of a Quadrotor-Slung-Load System
Authors: He Tongfu , Song Guangyi , Song Dalei , Lv Jiahui , Zhou Liqin
Published: December 2023

The presence of a slung-load during the flight of a quadrotor generates swing
effects that can greatly influence the dynamics of the quadrotor. These effects
have the potential to threaten the stability of the system’s attitude. This
study presents a disturbance compensation strategy that is designed based on the
utilization of an adaptive harmonic extended state observer (AHESO) in order to
solve this problem and achieve precise attitude control. To derive the
aforementioned algorithm, a comprehensive mathematical model for the
quadrotor-slung-load system is built. The periodic features of disturbance are
derived by considering the movement of the slung-load. Subsequently, by taking
the periodic features of the disturbances into account, the AHESO for accurate
disturbance estimation is designed. In this observer, an online frequency
estimator for the harmonic disturbances is introduced. Lyapunov theory is
introduced to examine the stability of the AHESO. In addition,
backstepping-based approach is employed to design an attitude controller for
accurate attitude tracking of the quadrotor. Analysis are conducted regarding of
the entire stability of the quadrotor-slung-load system. In the end, the
effectiveness of the designed method is verified by comparative simulations.
The ICE Model: Evaluating In-Cockpit Child-Centric Interaction
Solutions
Authors: Xu Jinghan , Hui Xinru , Wang Yixiang , Jia Qing
Published: December 2023

Effective smart cockpit interaction design can address the specific needs of
children, offering ample entertainment and educational resources to enhance
their on-board experience. Currently, substantial attention is focused on smart
cockpit design to enrich the overall travel engagement for children. Recognizing
the contrasts between children and adults in areas such as physical health,
cognitive development, and emotional psychology, it becomes imperative to
meticulously customize the design and optimization processes to cater explicitly
to their individual requirements. However, a noticeable gap persists in both
research methodologies and product offerings within this domain. This study
employs user survey to delve into children’s on-board experiences and
utilization of current child-centric in-cockpit interaction solutions (C-SI
Solutions), that over 50% of the interviewees (children) got on-board at least
several times per week and over half of the parents would pay for C-SI
Solutions, but less than 8% of the interviewees reported actual usage. By
employing an interdisciplinary approach that harmonizes Design Thinking and
Developmental Psychology, this research reveals that the traditional cockpit is
actually a liminal space for children, and introduces the ICE Model (Evaluation
Model for In-Cockpit Child-Centric Interaction Solutions) for providing insights
into C-SI solution design. This model is consisted of two modules: IPO-Based
Structured Module and I&C (Intelligence & Consciousness) Evaluation
Module. IPO-Based Structured Module is based on the IPO (Input-Process-Output)
Model and for interpreting C-SI Solution’s structure, so that to realize the
paradigm shift in Design Thinking. I&C Evaluation Module, the second one, is
for analyzing C-SI Solution’s psychological developmental function. The ICE
model is then applied to conduct market research, aiming to identify challenges
and shortcomings with current C-SI Solutions. Subsequently, this research offers
recommendations and possibilities for the improvement of designing C-SI
Solutions, that it requires not only seamless cooperation between designers and
engineers, but also interdisciplinary collaboration.
Departure Flight Delay Prediction and Visual Analysis Based on
Machine Learning
Authors: Qi Xinyue , Qian Pinzheng , Zhang Jian
Published: December 2023

Nowadays, the rapid growth of civil aviation transportation demand has led to
more frequent flight delays. The major problem of flight delays is restricting
the development of municipal airports. To further improve passenger
satisfaction, and reduce economic losses caused by flight delays, environmental
pollution and many other adverse consequences, three machine learning algorithms
are constructed in current study: random forest (RF), gradient boosting decision
tree (GBDT) and BP neural network (BPNN). The departure flight delay prediction
model uses the actual data set of domestic flights in the United States to
simulate and verify the performance and accuracy of the three models. This model
combines the visual analysis system to show the density of departure flight
delays between different airports. Firstly, the data set is reprocessed, and the
main factors leading to flight delays are selected as sample attributes by
principal component analysis. Secondly, the mean absolute error (MAE), mean
absolute percentage error (MAPE) and root mean square error (RMSE) were selected
as evaluation indexes to compare the prediction results of three different
models. The final results show that the departure flight delay prediction model
based on BPNN algorithm has faster solution speed and overcomes the over-fitting
problem, and has higher prediction accuracy and robustness. Based on the
algorithm developed in this paper, the airport system can be planned in a
targeted manner, thereby alleviating the pressure of air transportation and
reducing flight delays.
A Wind Tunnel Investigation on the Aerodynamics of the Propulsion
Wing for a Novel eVTOL Vehicle
Authors: Wang Junjie , Zhang Xinfeng , Han Yue
Published: December 2023

With increasing interest in the urban air traffic market for electric Vertical
Take-Off and Landing (eVTOL) vehicles, there are opportunities to enhance flight
performance through new technologies and control methods. One such concept is
the propulsion wing, which incorporates a cross-flow fan (CFF) at the wing's
trailing edge to drive the vehicle's flight. This article presents a wind tunnel
experiment aimed at analyzing the aerodynamic characteristics of the propulsive
wing for the novel eVTOL vehicle. The experiment encompasses variations in
angels of attack, free stream velocities and fan rotational speeds. The result
verifies that cross-flow fans offer unique flow control capabilities, achieving
a tested maximum lift coefficient exceeding 7.6. Since flow from the suction
surface is ingested into the CFF, the flow separation at large angle of attack
(up to 40°) is effectively eliminated. The aerodynamic performance of the
propulsive wing depends on the advance ratio and angle of attack. Generally,
with a high advance ratio and sufficient CFF power for flow control, the
airfoil's lift coefficient increases with angle of attack, while drag
coefficient decreases with higher fan rotational speeds. Additionally, this
study identifies improved flow control capability with the presence of a vortex
cavity. The propulsion wing shows promising application prospects for eVTOL
vehicle.
Wide-Range High-Confidence Surge Margin Estimation Method for
Aircraft Engine
Authors: Chen Qian , Sheng Hanlin , Liu Tong , Li Jiacheng
Published: December 2023

The confidence of the onboard adaptive model in estimating surge margin
significantly affects the operating stability in an aircraft engine’s active
surge margin control process. Unfortunately, the existing onboard adaptive
models lack high confidence, although wide-ranging in estimation, due to the
unknown surge boundaries in component characteristics. Therefore, this paper
first accurately estimates the actual surge margin during the engine operating
near-surge boundary using a pressure correlation measurement technology. Then,
innovatively, the estimated surge margin is used to correct the surge boundary
of the nonlinear onboard model of the engine to obtain the actual surge
boundary, thereby guaranteeing confidence. Finally, a nonlinear onboard adaptive
model based on an improved spherical unscented Kalman filter is employed to
achieve wide-range high-confidence surge margin estimation throughout the
engine’s life cycle. Simulation results demonstrate that the proposed method is
effective and has a high-confidence level in surge margin estimation, ensuring
estimation accuracy of over 95% for both standard and degraded engines, far
surpassing existing techniques. The proposed method provides a technical means
for sensing surge margin in future high-stability engine active control.
Improved Prandini Conflict Detection Algorithm Based on Trajectory
Prediction
Authors: Li Xinyue , Gong Fengxun
Published: December 2023

As a traditional probabilistic mid-term conflict detection algorithm, the
Prandini algorithm plays an essential role in ensuring flight safety in the
aircraft route area. For the issue of mutation error in the calculation results
of the Prandini algorithm, this research provides an improved Prandini conflict
detection algorithm. First, the integral of the standard Gaussian distribution
is solved using randomization. The minimum prediction interval moment is then
calculated, and the critical time points at which conflicts may exist before and
after that moment are approximated separately using a bisection method. N moment
values are selected uniformly within the time range formed by the two critical
time points. The instantaneous conflict probabilities for these N moments are
calculated and the maximum value is selected from them as a measure of the
likelihood of conflict between the two aircraft over the entire route for an
extreme case. Finally, a trajectory position prediction error model is built
using actual ADS-B data to verify the performance of this improved algorithm for
application in the no route change scenario and the multi-route scenario. The
experimental results show that compared with the original Prandini algorithm,
the method improves the stability of conflict detection and can meet the
requirements of air traffic control (ATC) for medium-term conflict
detection.
Lane Changing Comfort Trajectory Planning of Intelligent Vehicle
Based on Particle Swarm Optimization Improved Bezier Curve
Authors: Sun Liyou , Guo Rong
Published: December 2023

This paper focuses on lane-changing trajectory planning and trajectory tracking
control in autonomous vehicle technology. Aiming at the lane-changing behavior
of autonomous vehicles, this paper proposes a new lane-changing trajectory
planning method based on particle swarm optimization (PSO) improved third-order
Bezier curve path planning and polynomial curve speed planning. The position of
Bezier curve control points is optimized by the particle swarm optimization
algorithm, and the lane-changing trajectory is optimized to improve the comfort
of lane changing process. Under the constraints of no-collision and vehicle
dynamics, the proposed method can ensure that the optimal lane-changing
trajectory can be found in different lane-changing scenarios. To verify the
feasibility of the above planning algorithm, this paper designs the lateral and
longitudinal controllers for trajectory tracking control based on the vehicle
dynamic tracking error model. The simulation is carried out in the
Carsim-Simulink co-simulation platform. The simulation results show that the
trajectory planning method proposed in this paper can ensure the safety and
efficiency of lane changing of the vehicle in the process of lane changing, and
has better performance in ride comfort.
Robust Stabilized Control for Electric Vertical Take-Off and Landing
(eVTOL) Fixed-Wing Aircraft
Authors: Shi Jiekai , Li Wei , Wang Fang , Bai Jie
Published: December 2023

Electric vertical takeoff and landing (eVTOL) aircraft, which is used extensively
in both military and civilian fields, has the advantages of good
maneuverability, high cruising speed, and low requirements for the takeoff and
landing modes. Robust and stable control is crucial to ensuring its safety
because the dynamics model of an eVTOL aircraft will change significantly
between fixed-wing and vertical takeoff and landing mode. In this paper, we
first study the structural characteristics of the eVTOL aircraft and establish
its dynamic model by considering typical flight modes and mechanical parameters.
Then we design a closed-loop controller based on cascade PID technique. Finally,
the effectiveness of the control algorithms is verified based on the
semi-physical flight simulation platform, which can lower the development cost
of control algorithms significantly. The simulation results demonstrate that the
cascade PID control scheme accelerates the implementation of the robust
controller, and significantly enhance the stabilization control performance of
the aircraft in vertical takeoff and landing mode as well as autonomous
navigation mode.
EVTOL Flight Control System Safety: An Example of Application Using
MBSA
Authors: Adeline Romain , Wang Jia , Hua Angelina
Published: December 2023

Electrical Vertical Takeoff and Landing (eVTOL) vehicles hold great promises for
revolutionizing urban mobility. Their emergences as a transformative
transportation technology has led multiple Original Equipment Manufacturers
(OEM) competing for market share, with important variety of technical solutions,
all necessitating to demonstrate the compliance to safety requirements and
regulations. Model Based Safety Analysis (MBSA), newly introduced in ARP4761A
and based on compositional and modular representation of failure propagation
paths within one system, provides a unique opportunity to increase efficiency by
maximizing the possible reuse of safety analyses elements across multiple
architectures (“product line” philosophy). Generic library of safety models for
elements of variant architectures can be efficiently constructed using MBSA
techniques that can then support safety analyses on variant architectures or
architectures trade-off. This approach can facilitate a safety process that
enable customized safety solutions without complete re-engineering of the safety
analyses for each architecture.

The purpose of this paper is to present and illustrate one work performed on the
definition of a safe Flight Control System for eVTOL, leveraging the capacity of
a MBSA based approach to ensure high level of agility and rapid responsiveness.
The first sections will present the need, the MBSA approach and a general
modelling process that can be used to employ MBSA methodology. Then, an example
of eVTOL Flight Control System architecture and safety analyses will be detailed
to picture how MBSA, coupled with a generic component library, can provide an
easily adaptable safety solution. Finally, we discuss some possible next steps
and future work identified in order to certify a solution thanks to this
method.
Game Theory-Based Lane Change Decision-Making Considering Vehicle’s
Social Value Orientation
Authors: Zhang Mingshuai , Chu Duanfeng , Deng Zejian , Zhao Chenyang
Published: December 2023

Decision-making of lane-change for autonomous vehicles faces challenges due to
the behavioral differences among human drivers in dynamic traffic environments.
To enhance the performances of autonomous vehicles, this paper proposes a game
theoretic decision-making method that considers the diverse Social Value
Orientations (SVO) of drivers. To begin with, trajectory features are extracted
from the NGSIM dataset, followed by the application of Inverse Reinforcement
Learning (IRL) to determine the reward preferences exhibited by drivers with
distinct Social Value Orientation (SVO) during their decision-making process.
Subsequently, a reward function is formulated, considering the factors of
safety, efficiency, and comfort. To tackle the challenges associated with
interaction, a Stackelberg game model is employed. Finally, the effectiveness of
this approach is validated in diverse testing scenarios involving obstacle
vehicles characterized by different SVO types, namely Altruistic, Prosocial,
Egoistic, and Competitive. The simulation results indicate that this approach
can address behavioral differences introduced by different drivers in lane
change interactions and making more safe and efficient driving decisions at
appropriate times.
Overview and Research on Airworthiness and Safety of Electrical Propulsion and Battery Technologies in eVTOL
Authors: Ma Xin , Ding Shuiting
Published: December 2023

This overview and study article scrutinizes the evolution and challenges of electric vertical takeoff and landing aircraft (eVTOL), with a primary focus on airworthiness and safety certification. The paper discusses key issues such as high-energy-density aviation-grade batteries and the light weighting of electrical propulsion systems. Utilizing scientific models and real-world data, the study outlines the required battery technology and electrical propulsion specifications for eVTOLs with effective commercial load capabilities. For eVTOLs operating in the 300 km range, aviation-grade batteries must achieve energy densities between 300-600 wh/kg. For those covering a 600 km range, the energy density requirements exceed 600 wh/kg. Compliance with stringent safety standards, including triple certification by the FAA under 14 CFR Part 23, is imperative. This article conducted research and offered flowchart of the complicated FAA standard, which is rare in existing articles. This article also proposed better platform which is more conducive to testing the propulsion and battery systems as well as the overall design of electric aircraft, especially eVTOLs. By establishing this more advanced platform, we aim to engage industrial partners both in China and internationally in various aspects such as propulsion technology, battery and material technology, and the overall design, manufacturing, and operation of eVTOL to meet airworthiness and safety requirements.
Exploring High School Mathematics Teachers’ Experiences of Professional Development in the Integration of GeoGebra
Authors: Mokotjo Lindiwe Gloria
Published: December 2023

This study investigated how high school mathematics teachers in South Africa integrate GeoGebra, a free dynamic mathematics software program, into their teaching practices. The research explored teachers' perceptions of the training they received for the GeoGebra software, their ability to create and implement GeoGebra-based lessons, and their confidence in using it in the classroom. The study employed an interpretive research paradigm to gather insights through unstructured interviews with four purposefully selected teachers from South Africa's Northwest Province. Despite the absence of a structured training program, the study findings indicate teachers' enthusiasm for adopting GeoGebra. The study underscores the need for the Department of Basic Education to enhance support to address potential obstacles and the importance of aligning GeoGebra training with existing guidelines for integrating information and communication technologies within the Department of Basic Education and school management. In summary, this study provides valuable insights into how professional development impacts high school mathematics teachers' incorporation of GeoGebra, with implications for the design and implementation of future programs aimed at helping teachers integrate technology into their instructional practices.