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71.
David Kuťák Pere-Pau Vázquez Tobias Isenberg Michael Krone Marc Baaden Jan Byška Barbora Kozlíková Haichao Miao 《Computer Graphics Forum》2023,42(6):e14738
Visualization plays a crucial role in molecular and structural biology. It has been successfully applied to a variety of tasks, including structural analysis and interactive drug design. While some of the challenges in this area can be overcome with more advanced visualization and interaction techniques, others are challenging primarily due to the limitations of the hardware devices used to interact with the visualized content. Consequently, visualization researchers are increasingly trying to take advantage of new technologies to facilitate the work of domain scientists. Some typical problems associated with classic 2D interfaces, such as regular desktop computers, are a lack of natural spatial understanding and interaction, and a limited field of view. These problems could be solved by immersive virtual environments and corresponding hardware, such as virtual reality head-mounted displays. Thus, researchers are investigating the potential of immersive virtual environments in the field of molecular visualization. There is already a body of work ranging from educational approaches to protein visualization to applications for collaborative drug design. This review focuses on molecular visualization in immersive virtual environments as a whole, aiming to cover this area comprehensively. We divide the existing papers into different groups based on their application areas, and types of tasks performed. Furthermore, we also include a list of available software tools. We conclude the report with a discussion of potential future research on molecular visualization in immersive environments. 相似文献
72.
S. Matthiesen T. Gwosch T. Schäfer P. Dültgen C. Pelshenke H.-J. Gittel 《Forschung im Ingenieurwesen》2016,80(1-2):17-27
This article shows by experimental studies on angle grinders, how application-equivalent stresses on the components can be determined. For this purpose a distance measurement technique is applied with which the movement of the shaft is detected while the angle grinder is in operation. The research results support validation activities in product development and contribute to early validation. It helps to analyzing the dynamic and working life of the power tool and therefore construction targets are derived. The related applications are considered and power tools with measuring equipment in the lab are tested. The measurement results are presented and possible causes and effects on the life of the components are discussed. With the method of investigation it is possible to study the behavior of subsystems already in development phases in which the overall system is not physically present. 相似文献
73.
R. Strauss G. Angloher A. Bento C. Bucci L. Canonica X. Defay A. Erb F. v. Feilitzsch N. Ferreiro Iachellini P. Gorla A. Gütlein D. Hauff J. Jochum M. Kiefer H. Kluck H. Kraus J. C. Lanfranchi J. Loebell A. Münster C. Pagliarone F. Petricca W. Potzel F. Pröbst F. Reindl K. Schäffner J. Schieck S. Schönert W. Seidel L. Stodolsky C. Strandhagen A. Tanzke H. H. Trinh Thi C. Türkoglu M. Uffinger A. Ulrich I. Usherov S. Wawoczny M. Willers M. Wüstrich A. Zöller 《Journal of Low Temperature Physics》2016,184(3-4):866-872
74.
Comparison of the identification performance of conventional FEM updating and integrated DIC 下载免费PDF全文
Andre P. Ruybalid Johan P. M. Hoefnagels Olaf van der Sluis Marc G. D. Geers 《International journal for numerical methods in engineering》2016,106(4):298-320
Full‐field identification methods are increasingly used to adequately identify constitutive parameters to describe the mechanical behavior of materials. This paper investigates the more recently introduced one‐step method of integrated digital image correlation (IDIC) with respect to the most commonly used two‐step method of finite element model updating (FEMU), which uses a subset‐based DIC algorithm. To make the comparison as objective as possible, both methods are implemented in the most equivalent manner and use the same FE model. Various virtual test cases are studied to assess the performance of both methods when subjected to different error sources: (1) systematic errors, (2) poor initial guesses for the constitutive parameters, (3) image noise, (4) constitutive model errors, and (5) experimental errors. Results show that, despite the mathematical similarity of both methods, IDIC produces less erroneous and more reliable results than FEMU, particularly for more challenging test cases exhibiting small displacements, complex kinematics, misalignment of the specimen, and image noise. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
75.
T. Dubberstein M. Schürmann H. Chaves H.-P. Heller C. G. Aneziris 《International Journal of Thermophysics》2016,37(10):100
A novel vibrating finger viscometer for high-temperature measurement in liquid metals and alloys up to 1823 K was constructed. The dynamic viscosity (\(\eta \)) of the liquid fluid is measured as a product of \((\rho \cdot \eta )^{0.5}\) and the relative change of the field coil input for a constant amplitude recording at the resonant frequency of the oscillator. The viscometer was calibrated at 298 K using reference silicon oils with varying kinematic viscosities (\(\nu \)), \((0.79\hbox { to } 200)\times 10^{-6}\hbox { m}^{2}\cdot \hbox {s}^{-1}\). In the present study, the viscosity of liquid gold (\(99.99\,\%\) Au), silver (\(99.9\, \%\) Ag), and tin (\(99.9\,\%\) Sn) was measured. The viscosities expressed as an Arrhenius function of temperature are: The viscosity values are consistent within the range of available literature data.
相似文献
$$\begin{aligned} \hbox {for Au:}\quad \quad \hbox {ln }\eta= & {} -0.1990+\frac{2669}{T}\\ \hbox {for Ag:} \quad \quad \hbox {ln }\eta= & {} -0.4631+\frac{2089}{T}\\ \hbox {for Sn:} \quad \quad \hbox {ln }\eta= & {} -0.5472+\frac{671}{T} \end{aligned}$$
76.
Igor Solodov Markus Rahammer Nikolai Gulnizkij Marc Kreutzbruck 《Journal of Nondestructive Evaluation》2016,35(3):48
A selective acoustic activation of defects based on the concept of local defect resonance enables to enhance considerably the intensity of defect vibrations and makes it possible to reduce the input acoustic powers to the levels permissible for noncontact nondestructive inspection. Since for cm-size defects in composite materials, the LDR frequencies lie in the low kHz-range, the resonant noncontact activation shifts to an audible frequency range and can be provided by conventional sonic equipment. In this paper, the feasibility of the resonant noncontact inspection is validated for the most “problematic” methodologies of nonlinear, thermosonic and shearosonic NDE that usually require an elevated acoustic power and, therefore, a reliable contact between the specimen and the transducer. In contrast, the noncontact versions developed employ commercial loudspeakers which can simultaneously insonify large areas and be applied for a contactless sonic inspection of different materials and various scale components. 相似文献
77.
78.
Gian Luigi Angrisani Piriya Taptimthong Susanne Elisabeth Thürer Christian Klose Hans Jürgen Maier Marc Christopher Wurz Kai Möhwald 《Advanced Engineering Materials》2018,20(9)
79.
S Ewig A Glasmacher B Ulrich K Wilhelm H Sch?fer KH Nachtsheim 《Canadian Metallurgical Quarterly》1998,114(2):444-451
STUDY OBJECTIVE: To determine predictors of mortality from pulmonary infiltrates in neutropenic patients with acute leukemia during chemotherapy, and the significance of those factors related to the underlying malignancy and its therapy as well as of those related to the severity of the illness associated with pulmonary infiltrates. DESIGN: A historical cohort study. SETTING: A university teaching hospital and tertiary referral center. PATIENTS AND METHODS: Overall, 53 patients with neutropenia during chemotherapy and with first episodes of pulmonary infiltrates during a 4-year period were studied. Prognostic analysis included 38 variables. Multivariate analyses were performed by logistic regression. RESULTS: The survival rate from pneumonia was 57% (30/53). The following eight parameters were significantly associated with death in univariate analysis: comorbidity present; development of "late" pulmonary infiltrates (> or = 14 days after hospital admission); heart rate > or = 100 beats/min; a ratio heart rate/systolic blood pressure (HR/SBP) > or = 1.2; urea nitrogen > 7 mmol/L; radiographic score > or = 3; neutropenia < 1.0x10(9)/L at the treatment end point; and failed complete remission. In a multivariate model including only parameters available at diagnosis of pulmonary infiltrates, the presence of a ratio HR/SBP > or = 1.2 and of a radiographic score > or = 3 remained independently associated with death. In a second model also including the evolutionary parameter neutropenia < or = 1.0x10(9)/L at the treatment end point, both parameters remained significant together with neutropenia <1.0x 10(9)/L at the treatment end point. The presence of a ratio HR/SBP > or = 1.2 was a strong marker of early death. CONCLUSION: Both therapy- and malignancy-associated neutropenia as well as the severity of illness associated with pulmonary infiltrates are independent prognostic factors. Patients with a ratio HR/SBP > or = 1.2 at diagnosis of pulmonary infiltrates suffer from potentially reversible acute illness, are at risk for early death and, therefore, may be appropriate candidates for treatment in an ICU. 相似文献
80.
It is shown that several recursive least squares (RLS) type equalization algorithms such as, e.g., decisiondirected schemes and orthogonalized constant modulus algorithms, possess a common algorithmic structure and are therefore rather straightforwardly implemented on an triangular array (filter structure) for RLS estimation with inverse updating. While the computational complexity for such algorithms isO(N
2), whereN is the problem size, the throughput rate for the array implementation isO(1), i.e., independent of the problem size. Such a throughput rate cannot be achieved with standard (Gentleman-Kung-type) RLS/QR-updating arrays because of feedback loops in the computational schemes. 相似文献