36 research outputs found
レスポンシブルロボット -- 安全かつ生産的な人-ロボット協同作業のための新しいアプローチ
【学位授与の要件】中央大学学位規則第4条第1項【論文審査委員主査】新妻 実保子(中央大学理工学部准教授)【論文審査委員副査】梅田 和昇(中央大学理工学部教授)、大隅 久(中央大学理工学部教授)、橋本 秀紀(中央大学理工学部教授)、吉見 卓(芝浦工業大学工学部教授)博士(工学)中央大
Relaxation-Time Determination from Continuous-Microwave Saturation of EPR Spectra
Based on the theories of Portis and of Castner 50 years ago,
different continuous-wave measurement procedures for analyzing
the microwave saturation power dependence of inhomogeneously
broadened EPR lines were developed. Although these
procedures have been refined, they still use only a few selected
points on the saturation curve. A non-linear least-squares
procedure for analyzing the microwave-power dependence of
inhomogeneously broadened lines using all data points on a
saturation curve has been developed. This procedure provides a
simple alternative method to obtain magnetic relaxation data
when the more direct pulse-saturation techniques are not
available or are less suitable. The latter includes applications
of quantitative EPR such as dosimetry. Then microwave
saturation data should be obtained under conditions similar to
those used in the quantitative measurements, which are usually
made on first derivative spectra recorded using continuous-wave
spectrometers. Selected applications to benchmark literature
data and within the field of EPR dosimetry are discussed. The
results obtained illustrate that relaxation times comparable to
those yielded by various pulse-saturation EPR techniques can be
obtained. It appears as a systematic feature that, whenever the
pulse EPR data are fitted using bi-exponential functions, the
shortest relaxation times obtained are those that correspond best
to those measured using the current continuous-wave saturation
method
Review article - An evaluation of SAFIRE's potential to reduce the dose received by paediatric patients undergoing CT: a narrative review:Iterative reconstruction in ct
Introduction: The purpose of this review is to gather and analyse current research publications to evaluate Sinogram-Affirmed Iterative Reconstruction (SAFIRE). The aim of this review is to investigate whether this algorithm is capable of reducing the dose delivered during CT imaging while maintaining image quality. Recent research shows that children have a greater risk per unit dose due to increased radiosensitivity and longer life expectancies, which means it is particularly important to reduce the radiation dose received by children. Discussion: Recent publications suggest that SAFIRE is capable of reducing image noise in CT images, thereby enabling the potential to reduce dose. Some publications suggest a decrease in dose, by up to 64% compared to filtered back projection, can be accomplished without a change in image quality. However, literature suggests that using a higher SAFIRE strength may alter the image texture, creating an overly ‘smoothed’ image that lacks contrast. Some literature reports SAFIRE gives decreased low contrast detectability as well as spatial resolution. Publications tend to agree that SAFIRE strength three is optimal for an acceptable level of visual image quality, but more research is required. The importance of creating a balance between dose reduction and image quality is stressed. In this literature review most of the publications were completed using adults or phantoms, and a distinct lack of literature for paediatric patients is noted. Conclusion: It is necessary to find an optimal way to balance dose reduction and image quality. More research relating to SAFIRE and paediatric patients is required to fully investigate dose reduction potential in this population, for a range of different SAFIRE strengths
OPTIMAX research summer school: um projeto pedagógico para a promoção da investigação em radiologia
Porquê este projeto? Conhecimentos, aptidões, competências; desenvolvimento de competências (instrumentais, interpessoais, sistémicas); contributo para uma concepção de carácter multidimensional do estudante, preparando-o para apreender a importância da investigação, preparando-o para uma profissão de saúde; as novas soluções tecnológicas, a par da inovação e a mudança nos cuidados de saúde e dos processos de trabalho, constituem hoje os desafios do presente e do futuro para os profissionais de saúde [o desenvolvimento da tecnologia e da informática, a educação e a prática baseada na evidência (investigação), as mudanças nos processos de trabalho, o trabalho em equipa, a dimensão internacional]; a investigação e o seu impacto na profissão (desenvolvimento de conhecimentos próprios das profissões, autonomia, impacto positivo nas práticas profissionais, benefício do doente); a investigação auxilia no processo de definição dos parâmetros de uma profissão (nenhuma profissão terá um desenvolvimento sustentado sem o contributo da investigação; é através da investigação que se constitui um domínio de conhecimentos baseados na evidência que permitam as boas práticas); apostar num projeto associado à investigação, com uma base científica que contribua para uma melhor educação e prática profissional visando assegurar a credibilidade da profissão; aprendizagem centrada no estudante; adopção de metodologias de ensino que promovam a autonomia, o raciocínio, a capacidade crítica e a resolução de problemas
Review article - An evaluation of SAFIRE's potential to reduce the dose received by paediatric patients undergoing CT: a narrative review:Iterative reconstruction in ct
An evaluation of SAFIRE’s potential to reduce the dose received by paediatric patients undergoing CT: a narrative review
Introduction: The purpose of this review is to gather and analyse current research publications to evaluate Sinogram-Affirmed Iterative Reconstruction (SAFIRE). The aim of this review is to investigate whether this algorithm is capable of reducing the dose delivered during CT imaging while maintaining image quality. Recent research shows that children have a greater risk per unit dose due to increased radiosensitivity and longer life expectancies, which means it is particularly important to reduce the
radiation dose received by children. Discussion: Recent publications suggest that SAFIRE is capable of reducing image noise in CT images, thereby enabling the potential to reduce dose. Some publications suggest a decrease in dose, by up to 64% compared to filtered back projection, can be accomplished without a change in image quality. However, literature suggests that using a higher SAFIRE strength may alter the image texture, creating an overly ‘smoothed’ image that lacks contrast. Some literature reports SAFIRE gives decreased low contrast detectability as well as spatial resolution. Publications tend to agree that SAFIRE strength three is optimal for an acceptable level of visual image quality, but more research is required. The importance of creating a balance between dose reduction and image quality is stressed. In this literature review most of the publications were completed using adults or phantoms, and a distinct lack of literature for paediatric patients is noted. Conclusion: It is necessary to find an optimal way to balance dose reduction and image quality. More
research relating to SAFIRE and paediatric patients is required to fully investigate dose reduction potential in this population, for a range of different SAFIRE strengths
Maintaining image quality for paediatric chest CTs while lowering dose: FBP versus SAFIRE
Objectives: Children have a greater risk from radiation, per unit dose, due to increased radiosensitivity and longer life expectancies. It is of paramount importance to reduce the radiation dose received by children. This research concerns chest CT examinations on paediatric patients. The purpose of this study was to compare the image quality and the dose received from imaging with images reconstructed with filtered back projection (FBP) and five strengths of Sinogram-Affirmed Iterative Reconstruction (SAFIRE). Methods: Using a multi-slice CT scanner, six series of images were taken of a paediatric phantom. Two kVp values (80 and 110), 3 mAs values (25, 50 and 100) and 2 slice thicknesses (1 mm and 3 mm) were used. All images were reconstructed with FBP and five strengths of SAFIRE. Ten observers evaluated visual image quality. Dose was measured using CT-Expo. Results: FBP required a higher dose than all SAFIRE strengths to obtain the same image quality for sharpness and noise. For sharpness and contrast image quality ratings of 4, FBP required doses of 6.4 and 6.8 mSv respectively. SAFIRE 5 required doses of 3.4 and 4.3 mSv respectively. Clinical acceptance
rate was improved by the higher voltage (110 kV) for all images in comparison to 80 kV, which required a higher dose for acceptable image quality. 3 mm images were typically better quality than 1 mm images. Conclusion: SAFIRE 5 was optimal for dose reduction and image quality
A Proactive Strategy for Safe Human-Robot Collaboration based on a Simplified Risk Analysis
Facilitators for and barriers to radiography research in public healthcare in Nordic countries
Introduction: It has been suggested that the future of diagnostic imaging relies on engagement in research and evidence-based practice. This implies a role transition from a clinical radiographer to a clinical radiographer-researcher. Clinical radiographers’ stimuli for engaging in research in Nordic countries are unknown. This study aimed to address this gap.Methods: Cross-sectional data collection via an online questionnaire on facilitators for and barriers to participation in radiography research was carried out among 507 clinical radiographers in public healthcare in the Nordic countries: Denmark, Finland, Norway and Sweden.Results: Support from colleagues (odds ratio [OR] 2.62) and other professionals (OR 2.74), and self-esteem in research skills (OR ≥ 2.21), were facilitators for radiography research. Lack of knowledge and skills to conduct research (OR 2.48) was revealed to hinder radiographers’ participation in research. The absence of a radiography research culture in the workplace explained non-participation in research (OR 1.75).Conclusion: This study revealed significant factors for clinical radiographers’ participation in research.Implications for practice: A strategy for establishing a radiography research culture in healthcare is proposed that is novel for the context. Management support for knowledge development and activity leading to inter-professional research projects across knowledge fields, provision of a radiography research lead and acknowledgement of radiography research among colleagues signify the establishment of the culture. These prerequisites might provide a paradigm change towards not only the symbiosis of a clinical radiographer and an autonomous researcher but also a partner who adds radiography research to evidence-based practice in diagnostic imaging.</p
Publication activities among the radiography sector in Norway
Aim To give an overview over journals chosen for publication by the radiography field. Background Traditionally, the professional development of radiography was dominated by other disciplines, e.g. radiology, physics, sociology and nursing. The move into the higher education sector led radiographers be additionally encouraged in research activities. Evidence based practice is an approach to clinical problem solving and health care provision based on "good evidence". Research papers are an important part. Till date, the publication activities and choose of journals among Norwegian radiography staffs have been unknown. Conclusions The wide list of journals chosen illustrates a broad underpinning of radiography. Radiography science in Norway has already shown considerable development and achieved many substantial and structural criteria set for independent academic disciplines.Aim To give an overview over journals chosen for publication by the radiography field. Background Traditionally, the professional development of radiography was dominated by other disciplines, e.g. radiology, physics, sociology and nursing. The move into the higher education sector led radiographers be additionally encouraged in research activities. Evidence based practice is an approach to clinical problem solving and health care provision based on "good evidence". Research papers are an important part. Till date, the publication activities and choose of journals among Norwegian radiography staffs have been unknown. Conclusions The wide list of journals chosen illustrates a broad underpinning of radiography. Radiography science in Norway has already shown considerable development and achieved many substantial and structural criteria set for independent academic disciplines