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排序方式: 共有1110条查询结果,搜索用时 15 毫秒
11.
Kerstin A. Kessel Christian Bohn Uwe Engelmann Dieter Oetzel Nina Bougatf Rolf Bendl Jürgen Debus Stephanie E. Combs 《Computer methods and programs in biomedicine》2014
In radiation oncology, where treatment concepts are elaborated in interdisciplinary collaborations, handling distributed, large heterogeneous amounts of data efficiently is very important, yet challenging, for an optimal treatment of the patient as well as for research itself. This becomes a strong focus, as we step into the era of modern personalized medicine, relying on various quantitative data information, thus involving the active contribution of multiple medical specialties. Hence, combining patient data from all involved information systems is inevitable for analyses. Therefore, we introduced a documentation and data management system integrated in the clinical environment for electronic data capture. We discuss our concept and five-year experience of a precise electronic documentation system, with special focus on the challenges we encountered. We specify how such a system can be designed and implemented to plan, tailor and conduct (multicenter) clinical trials, ultimately reaching the best clinical performance, and enhancing interdisciplinary and clinical research. 相似文献
12.
Nina Streeck 《Ethik in der Medizin》2016,28(2):135-148
Definition of the problem This article takes a critical look at the current theory and practice of palliative care (PC), how it deals with death and dying, and the underlying guiding principle of a good death. Thereby, Foucault’s concept of biopower is utilized. Argument Because PC aims to facilitate a good death, manifold criteria and measures have been developed that help plan interventions and determine their success. In light of the concept of biopower, certain problematic aspects of this development become manifest that usually remain hidden in the bioethical discourse. Conclusion A goal of PC is to improve the quality of life of the dying and therefore not only treats physical symptoms but also psychological, social, and spiritual suffering; thus, it commits itself to maximizing life in a way that can become overdemanding for the individual and possibly does not satisfy the patient’s real needs. 相似文献
13.
半导体开关是影响电压源整流器VSR(voltage source rectifier)系统整体故障率的重要因素。为此,提出一种基于电流畸变特性的三相开路故障诊断系统,该系统由诊断模块、寄存器模块和决策模块组成。诊断模块使用滞环比较器来判断电流的变化趋势,从而诊断开路OC(open-circuit)故障;寄存器模块用于实现多开关OC故障诊断;决策模块用于输出最终结果。实验结果表明,该方法能够正确实现包括6种单开关故障和15种不同的双开关故障在内的故障诊断,故障诊断准确性好。此外,所提方法在负载突变、不同功率因数、电网电压不平衡和畸变以及不同的交流滤波器结构条件下均具有良好的抗干扰性能和较强的鲁棒性,平均诊断时间仅为3.68 ms。 相似文献
14.
Nina Qian Hari Krishna Bisoyi Meng Wang Shuai Huang Zhongcheng Liu Xu-Man Chen Jun Hu Hong Yang Quan Li 《Advanced functional materials》2023,33(16):2214205
In recent years, although light-driven soft actuators have attracted intense scientific attention and achieved remarkable progress, the design and construction of an intelligent robotic system with maneuverability, self-adaptability, untethered control, and greater freedom of action, in particular the omnidirectional motion capability on a plane, remains challenging. Herein, four types of photo-thermal fillers and an unprecedented twist-bend actuation mode is introduced into a liquid crystal elastomer-based soft robot. The obtained twist-bend crawling robot not only exhibits in situ rotation, four-way turning, and four-way linear motion under light irradiation with four wavelength bands (520, 655, 808, and 980 nm), but also demonstrates the ability to avoid obstacles in complex geographical environments. This work may bring a new perspective for fabrication and development of soft robots that can adapt to dynamic and complex environmental conditions. 相似文献
15.
With the continually increasing complexity of e-learning environments, there is a need for integrating concepts of cognitive load theory (CLT) with concepts of human–computer interaction (HCI). Basic concepts of both fields were reviewed and contrasted. A literature review was conducted within the literature database “The Guide to Computing Literature,” searching for “cognitive load theory” and “Sweller.” Sixty-five publications contained “cognitive load” in their titles or abstracts. Each publication was checked to see whether it contained the concepts of intrinsic, extraneous, or germane cognitive load. The review showed that CLT concepts have been adopted in HCI. However, the concept of germane cognitive load has attracted less attention up to the present time. Two conceptual models are proposed. The first model divides extraneous cognitive load into load induced by the instructional design and load caused by software usage. The model clarifies the focus of traditional usability principles and of existing instructional design principles derived from CLT. The second model fits CLT concepts into the basic components of user-centered design. The concept of germane cognitive load illustrates that an increase of cognitive load can be desirable when designing e-learning environments. Areas for future interdisciplinary research are sketched. 相似文献
16.
17.
Nina P.G. Salau Gustavo Alberto Neumann Jorge O. Trierweiler Argimiro R. Secchi 《Journal of Process Control》2009,19(3):530-538
In an industrial gas-phase polyethylene reactor, the safe operating range of temperature is rather narrow. Even within this temperature range, temperature excursions must be avoided because they can result in low catalyst productivity and significant changes in product properties. If the manipulated variable for temperature control saturates (i.e., the cooling water valve position is completely open), then the reactor operates without a feedback temperature controller, leading to oscillatory behavior and limit cycles. In this work, it has been demonstrated that the saturation in the manipulated variable and the complex non-linear dynamic behavior are removed when auxiliary manipulated variables, obtained by bifurcation analysis, are used in a multivariable control strategy for the reactor temperature control. Two control structures are proposed and compared considering their impact in the reactor production and polymer melt index. In the first control structure, the designed PID controller for the reactor temperature is considered and a switching strategy with a PI controller for the auxiliary manipulated variables is included. In the second control structure, the designed PID controller for the reactor temperature is also used, however, a MPC controller for the auxiliary manipulated variables is considered. The results suggest that the use of gain-scheduling strategy in the PID temperature controller with a MPC controller for the auxiliary manipulated variables avoids the saturation of the manipulated variable and, hence, the undesired non-linear dynamic behavior, reducing the production loss and improving the product quality. 相似文献
18.
Exploring indicators for quantifying surface urban heat islands of European cities with MODIS land surface temperatures 总被引:2,自引:0,他引:2
The term urban heat island describes the phenomenon of altered temperatures in urban areas compared to their rural hinterlands. A surface urban heat island encompasses the patterns of land surface temperatures in urban areas. The classical indicator to describe a surface urban heat island is the difference between urban and rural surface temperatures. However, several other indicators for this purpose have been suggested in the literature. In this study, we compared the eleven different indicators for quantifying surface urban heat islands that were most frequently used in recent publications on remote sensing-based urban heat island assessments. The dataset used here consists of 263 European cities with monthly mean temperatures from MODIS data products for July 2002, January 2003 and July 2003. We found that (i) the indicators individually reveal diurnal and seasonal patterns but show rather low correlations over time, and (ii) for single points in time, the different indicators show only weak correlations, although they are supposed to quantify the same phenomenon. Differentiating cities according to thermal climate zones increased the relationships between the indicators. Thus, we can identify temporal aspects and indicator selection as important factors determining the estimation of urban heat islands. We conclude that research should take into account the differences and instabilities of the indicators chosen for quantifying surface urban heat islands and should use several indicators in parallel for describing the surface urban heat island of a city. 相似文献
19.
Hoelzl C Lorenz O Haudek V Gundacker N Knasmüller S Gerner C 《Proteomics. Clinical applications》2008,2(1):108-117
Epidemiological studies indicate a correlation of cruciferous vegetables consumption with reduced incidence of cancer. This study was designed to investigate molecular mechanisms, which may help to understand the beneficial effects of Brussels sprout consumption. In order to avoid the limitations of in vitro model systems, we performed a dietary intervention study with five participants. We investigated, whether sprout consumption affects the proteome profile of primary white blood cells. In order to achieve maximal sensitivity in detecting specific adaptive proteome alterations, we metabolically labelled freshly isolated cells in the presence of 35S‐methionine/cysteine and performed autoradiographic quantification of protein synthesis. Proteins were separated by 2‐DE and spots of interest were cut out, digested and identified by MS. After the intervention, we found a significant up‐regulation of the synthesis of manganese superoxide dismutase (1.56‐fold) and significant down‐regulation of the synthesis of heat shock 70 kDa protein (hsp70; 2.27‐fold). Both proteins play a role in malignant transformation of cells. Hsp‐70 is involved in the regulation of apoptosis, which leads to elimination of cancer cells, while SOD plays a key role in protection against reactive oxygen species mediated effects. Our findings indicate that the alteration of the synthesis of these proteins may be involved in the anticarcinogenic effects of cruciferous vegetables, which was observed in earlier laboratory studies with animals. 相似文献
20.