An idea for implementing reconfigurable matching networks to realize a tunable diplexer is investigated and demonstrated. The reconfigurable matching networks ensure that the rejection band impedance ...of every filter is transformed to an open circuit over a wide range of frequencies, allowing two tunable filters to be connected together to form a tunable diplexer without affecting each other. The tunable diplexer is built using Schottky diodes and combline resonators on Duroid substrates, and can operate from 1.4 to 2.3 GHz with a closest frequency separation of 110 MHz. Measurements show virtually no difference in the frequency response between a standalone filter and a filter placed in the tunable diplexer. The work shows that a wideband tunable diplexer can therefore be realized using tunable bandpass filters and reconfigurable matching networks.
This paper presents a novel tunable dual-band bandstop filter based on doubly tuned RF transformers. This design results in two distinct notch frequencies in a single resonator using silicon varactor ...diodes. The 2-pole tunable dual-band bandstop filters are implemented using printed circuit board (PCB) transformers and air-coil transformers. With PCB transformers, the lower frequency can be tuned at 513-845 MHz while the higher frequency can be tuned at 715-1151 MHz with a notch level > 16 dB. With air-coil transformers, a single-band 2-pole notch filter with wide rejection bandwidth is achieved. The design results in 604-982 MHz tuning with a 20-dB rejection bandwidth of 27-45 MHz. Also, by implementing a series varactor in a transformer, the separation between two coupled frequencies can be changed. The topology can be easily extended to higher order filters and design equations are presented.
From the perspective of satisfaction, physical and mental health, and re-travel, this study explored whether the development of religious and cultural tourism could construct a sustainable and ...friendly life and leisure environment for the elderly to promote physical and mental health. This research adopted a mixed method, collected 700 questionnaires, used SPSS 22.0 statistical software, and analyzed basic statistics, t-test, and PPMCC test. Then, the researchers conducted semi-structured interviews, collected the opinions of six interviewees, and finally analyzed with multiple checks Law discussion. The results found that people of different genders and stakeholders had different opinions about DIY activities on leisure satisfaction, featured itineraries, relaxation areas, signs and instructions, community association and service center services, historical landmarks, and public transportation. They found people’s life satisfaction in physical and mental health was increased, their headaches or pressures on the top of their heads were relieved, backache problems were reduced, and they were no longer anxious and lost tempers. They had a greater willingness to revisit some places and share experiences. This study found significant differences among these topics (p < 0.01). Women, residents, and tourists had different opinions. In addition, although the natural environment landscape and feelings have the greatest influence, the better the physical and mental health was improved, the better the willingness to travel. However, the more perfect the local construction and development, the less favorable to attract people to engage in leisure activities or tourism consumption.
The present work is aimed at solving the difficulty of BC big data information analysis and the defects of traditional BC platform visual interface (VI), such as nonstandard layout, unreasonable ...color use, unclear guidance, and increased user learning cost. Firstly, this paper expounds on BC technology, the related theory of information visualization (IV), and the IV design method of BC-generated big data. Secondly, by formulating the user experience design strategy, a big data visual information sharing platform (ISP) based on behavior experience (BE) is designed. Finally, the system performance is tested. The results show that (i) the proposed BE-based big data visual ISP has the basic functions of information query and module jump. The overall interface of the platform is simple and tidy, the information layout is reasonable, the presentation method is more intuitive, and the visual effect is better. (ii) The host throughput of each system module when processing business is greater than 100 times/s, and the success rate (SR) of event handling is greater than 99%. The average response time (RT) of terminal processing is less than 0.3 s, and the average RT of the terminal side is less than 0.4 s. The system’s central processing unit (CPU) occupancy rate (OR) shall be controlled below 30%. The memory OR shall be below 30%, both of which are lower than the standard value, and the system performance meets the standard. To sum up, the proposed ISP has basic functions and ensures good operation performance. It is suitable for the IV of BC-generated big data. The purpose is to provide important technical support for the IV of BC-generated big data and improve the efficiency of users’ data information acquisition and analysis.
Abstract Introduction Neuroblastoma is a pediatric malignancy with heterogeneous clinical outcomes. Our aim was to identify prognostic genetic markers for patients with neuroblastoma, who were ...treated with the Taiwan Pediatric Oncology Group (TPOG) neuroblastoma N2002 protocol, to improve risk stratification and inform treatment. Methods Our analysis was based on 53 primary neuroblastoma specimens, diagnosed pre‐chemotherapy, and 11 paired tumor relapse specimens. Deep sequencing of 113 target genes was performed using a custom panel. Multiplex ligation‐dependent probe amplification was performed to identify clinical outcomes related to copy‐number variations. Results We identified 128 variations associated with survival, with the number of variations being higher in the relapse than that in the diagnostic specimen ( p = .03). The risk of event and mortality was higher among patients with a tumor mutational burden ≥10 than that in patients with a lower burden ( p < .0001). Multivariate analysis identified tumor mutational burden, MYCN amplification, and chromosome 3p deletion as significant prognostic factors, independent of age at diagnosis, sex, and tumor stage. The 5‐year event‐free survival and overall survival rate was lower among patients with high tumor burden than in patients with low tumor burden. Furthermore, there was no survival of patients with an ALK F1147L variation at 5 years after diagnosis. Conclusions Genome sequencing to determine the tumor mutational burden and ALK variations can improve the risk classification of neuroblastoma and inform treatment.
•Radiologist workload in Taiwan was greater than that in western countries.•Workload growth was confounded by ageing population and ever-changing imaging technologies.•Increasing radiologist ...recruitment activities is needed.
The aim of this study was to investigate associations between workforce and workload among radiologists in Taiwan.
Data for the period 2000–2020 describing the demand for imaging services and radiologists have been obtained from databases and statistical reports of the Ministry of Health and Welfare. The future demand for radiologists was based on Taiwanese people aged 40 and over.
The workforce of Taiwan's radiologists has increased by 6 % annually over the past 20 years (from 450 to 993), performing 2125, 3202 and 3620 monthly examinations (mainly conventional radiography and CT) in medical centers, regional hospitals and district hospitals. Between 2000 and 2020, the use of CT and MRI increased by more than 3.5 times. Demand for interventional radiology also increased by 1.77 times, 2.25 times, and 5 times, respectively. To maintain this volume of services in 2040, at least 1168 radiologists are needed, about 1.18 times more in 2020.
Taiwan has 2.4 to 2.9 times fewer radiologists than the United States and 3 times fewer than Europe, while the annual workload is approximately 2 to 3.4 times greater than that of the United States and 1.4 to 2.5 times greater than that of the United Kingdom. This report may serve as a reference for policy makers who address the challenges of the growing workload among radiologists in countries of similar situations.
The emergence of intelligent technology has brought a particular impact and allows for virtuality-reality interaction in the educational field. In particular, digital twins (DTs) feature ...virtuality-reality symbiosis, solid virtual simulation, and high real-time interaction. It has also seen extended applications to the field of education. This study optimizes the design of the visual communication (Viscom) course based on the deep learning (DL) algorithm. Firstly, the theory of DL is analyzed following the relevant literature, and the typical DL networks, network structures, and related algorithms are introduced. Secondly, Viscom technology is expounded, and DL technology is applied to the Viscom course. Then, the applicability and feasibility of DL in the Viscom course are analyzed through a questionnaire survey (QS) design by collecting students’ attitudes towards Viscom courses before and after the experiment. After introducing DL into the Viscom course, the results show that students’ learning interest and satisfaction with the practical knowledge mastery have increased. However, the satisfaction with theoretical knowledge mastery before practical courses has decreased; overall, the teaching effect of the Viscom course has been improved. Therefore, the introduction of DL into the DT-enabled Viscom can provide a reference for developing the Viscom course. The research content offers technical support (TS) for integrating DT technology and modern education.
We reported a series of well-characterized di-nuclear nickel catalysts containing 1,3-diamine-bis(benzotriazole phenolate) derivatives for high-performance copolymerization of CO
2
and epoxides. The ...di-nickel di-acetate complex
1
was found to be a highly active catalyst to alternatingly copolymerize CO
2
with cyclohexene oxide (CHO), producing poly(cyclohexene carbonate)s (PCHCs) with a high turnover frequency (TOF) up to 7800 h
−1
under optimized conditions. Interestingly, complex
1
also appears to be the first example of nickel-catalyzed CO
2
-copolymerization with CHO that could proceed at 1 atm CO
2
pressure. Not only has the excellent catalysis of CO
2
/CHO copolymerization by di-Ni
1
been enabled, but also
1
has been further applied to effectively catalyze the copolymerization of CO
2
with 4-vinyl-1,2-cyclohexene oxide or cyclopentene oxide (CPO) to obtain the corresponding polycarbonates. Particularly,
1
was also reported for the first time to be highly efficient for nickel-catalyzed CO
2
/CPO copolymerization and enabled the formation of poly(cyclopentene carbonate)s with a TOF > 700 h
−1
and excellent carbonate linkage contents (>99%). Kinetic studies of the Ni-catalyzed CO
2
-copolymerization of CHO were performed and the activation energy for PCHC formation by
1
is 60.6 kJ mol
−1
.
Catalyst
1
was reported for the first time to be effective for nickel-catalyzed CO
2
/CHO copolymerization at 1 atm CO
2
pressure.
A novel compact dual-band pattern diversity antenna is proposed. Dual-band reconfigurable frequency-selective reflectors are designed and applied to form a right-angle corner reflector antenna with ...reconfigurable patterns. With only one switch, the reconfigurable frequency-selective reflector can be controlled to be transmissive or reflective to vertically polarized waves at 2.45 and 5.25 GHz. By changing the combinations of the switch states, multiple patterns can be obtained. A dual-band feeding antenna designed via using the coupling effects is made to achieve well-matching conditions in all circumstances corresponding to various switch states at both frequencies. The measured results show good agreement with the calculated ones and demonstrate good pattern diversity virtues.
Radiosensitivity in the breasts increases the risk of carcinogenesis from exposure to the ionizing radiation of computed tomography (CT) administered in the course of medical attention. Bismuth ...shielding techniques have been used to reduce radiation, but image noise increased, degrading image quality.
The aim of this study was to investigate how the use of iterative reconstruction (IR) combined with bismuth shielding influences image quality.
Women aged at least 20 years with body mass indexes <28 were recruited and randomly assigned to 1 of 3 CT scanning protocols without shielding, with a bismuth breast shield before the scout view, or with a bismuth breast shield after the scout view. All obtained images were reconstructed using an IR algorithm. To evaluate radiation dose, 2 Gafchromic films were placed over the clothes, 1 near each nipple.
Average dose reduction was significant (27.99%, P < .05) when bismuth shielding was applied after the scout view. Using the contrast-to-noise ratio, the image quality was found to be superior when the IR algorithm was applied. Using quantitative evaluations by 2 radiologists applying a 4-point Likert scale, significant differences in image quality were not found among the 3 protocols.
Bismuth breast shields, particularly when used after acquiring scout images, are effective at reducing radiation dose without undermining the diagnostic value of the images when the IR technique is applied.
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