Gas migration model based on overburden strata fracture evolution law in three dimensional mine-induced stress conditions

: In contrast to their almost unlimited potential for expansion in vivo and despite years of dedicated research and optimization of expansion protocols, the expansion of Hematopoietic Stem Cells (HSCs) in vitro remains remarkably limited. Increased understanding of the mechanisms that are involved in maintenance, expansion and differentiation of HSCs will enable the development of better protocols for expansion of HSCs. This will allow procurement of HSCs with long-term engraftment potential and a better understanding of the effects of the external influences in and on the hematopoietic niche that may affect HSC function. During collection and culture of HSCs, the cells are exposed to suboptimal conditions that may induce different levels of stress and ultimately affect their self-renewal, differentiation and long-term engraftment potential. Some of these stress factors include normoxia, oxidative stress, extra-physiologic oxygen shock/stress (EPHOSS), endoplasmic reticulum (ER) stress, replicative stress, and stress related to DNA damage. Coping with these stress factors may help reduce the negative effects of cell culture on HSC potential, provide a better understanding of the true impact of certain treatments in the absence of confounding stress factors. This may facilitate the development of better ex vivo expansion protocols of HSCs with long-term engraftment potential without induction of stem cell exhaustion by cellular senescence or loss of cell viability. This review summarizes some of available strategies that may be used to protect HSCs from culture-induced stress conditions.

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Holographic Blind Watermarking Algorithm of Three- Dimensional Mesh Model Based on QR Decomposition

The Open Automation and Control Systems Journal ◽

10.2174/1874444301507010047 ◽

2015 ◽

Vol 7 (1) ◽

pp. 47-57

Author(s):

Wenju Wang ◽

Liujie Sun ◽

Qin Yang ◽

Zhang Xuan

Keyword(s):

Three Dimensional ◽

Qr Decomposition ◽

Blind Watermarking ◽

Model Based ◽

Mesh Model

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Design and Marker-Based Validation of a Biplane Fluoroscopy System for Studying the Foot and Ankle

ASME 2012 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2012-80906 ◽

2012 ◽

Author(s):

Joseph M. Iaquinto ◽

Richard Tsai ◽

Michael J. Fassbind ◽

David R. Haynor ◽

Bruce J. Sangeorzan ◽

...

Keyword(s):

Precise Measurement ◽

Three Dimensional ◽

The Body ◽

Initial Evaluation ◽

Foot And Ankle ◽

Research Groups ◽

The Past ◽

Model Based ◽

Biplane Fluoroscopy ◽

Model Based Analysis

The ability to accurately measure three dimensional (3D) bone kinematics is key to understanding the motion of the joints of the body, and how such motion is altered by injury, disease, and treatment. Precise measurement of such kinematics is technically challenging. Biplane fluoroscopy is ideally suited to measure bone motion. Such systems have been developed in the past for both radiographic stereo-photogrammetric analysis (RSA) [1] and the more challenging model-based analysis [2]. Research groups have studied the knee [3,4], shoulder [5] and ankle [6] motion with similar techniques. The work presented here is an initial evaluation of the performance of our system, i.e., a validation that this in-house system can detect magnitudes of motion on-par with other existing systems.

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Model-Based Three-Dimensional Vision System

10.1117/12.949125 ◽

1989 ◽

Author(s):

Keiichi Kemmotsu ◽

Yuichi Sasano ◽

Katsumi Oshitani

Keyword(s):

Vision System ◽

Three Dimensional ◽

Model Based ◽

Three Dimensional Vision

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Undrained deformation characteristics of loose sand under three-dimensional stress conditions

International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts ◽

10.1016/0148-9062(82)91692-8 ◽

1982 ◽

Vol 19 (2) ◽

pp. 27

Keyword(s):

Three Dimensional ◽

Stress Conditions ◽

Deformation Characteristics ◽

Loose Sand

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An Approach to Generate Three Dimensional Machining Process Model According to Information from Design Model Based on Definition

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.693.1684 ◽

2016 ◽

Vol 693 ◽

pp. 1684-1692 ◽

Cited By ~ 1

Author(s):

Hong Lei Zhang ◽

Wen He Liao ◽

Yu Guo ◽

Wen An Yang

Keyword(s):

Process Model ◽

Three Dimensional ◽

Design Model ◽

Machining Process ◽

Model Generation ◽

Geometric Models ◽

Model Based

Faced with the problem of generation for 3D machining process model, an approach to generate three dimensional machining process model according to information from design model based on definition is proposed. Compared with the existing methods, the approach utilizes multiple information of design model based on definition and takes many phases into consideration of 3D process model generation. The structure of 3D machining process model is defined and the course of 3D process model generation is researched, including multiple information acquirement, generation of procedure geometric models and annotation. Finally, the framework of system and application for 3D machining process model generation are presented for validation purposes.

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Minimization of the Local Residual Stress in 3D Flip Chip Structures by Optimizing the Mechanical Properties of Electroplated Materials and the Alignment Structure of TSVs and Fine Bumps

ASME 2011 Pacific Rim Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Systems, MEMS and NEMS: Volume 1 ◽

10.1115/ipack2011-52063 ◽

2011 ◽

Author(s):

Kohta Nakahira ◽

Hironori Tago ◽

Fumiaki Endo ◽

Ken Suzuki ◽

Hideo Miura

Keyword(s):

Mechanical Properties ◽

Residual Stress ◽

Thermal Deformation ◽

Flip Chip ◽

Flexural Rigidity ◽

Three Dimensional ◽

Strain Gauges ◽

Copper Interconnection ◽

Induced Stress ◽

Alignment Structure

Since the thickness of the stacked silicon chips in 3D integration has been thinned to less than 100 μm, the local thermal deformation of the chips has increased drastically because of the decrease of the flexural rigidity of the thinned chips. The clear periodic thermal deformation and thus, the thermal residual stress distribution appears in the stacked chips due to the periodic alignment of metallic bumps, and they deteriorate the reliability of products. In this paper, the dominant structural factors of the local residual stress in a silicon chip are discussed quantitatively based on the results of a three-dimensional finite element analysis and the measurement of the local residual stress in a chip using stress sensor chips. The piezoresistive strain gauges were embedded in the sensor chips. The length of each gauge was 2 μm, and an unit cell consisted of 4 gauges with different crystallographic directions. This alignment of strain gauges enables to measure the tensor component of three-dimensional stress fields separately. Test flip chip substrates were made by silicon chip on which the area-arrayed tin/copper bumps were electroplated. The width of a bump was fixed at 200 μm, and the bump pitch was varied from 400 μm to 1000 μm. The thickness of the copper layer was about 40 μm and that of tin layer was about 10 μm. This tin layer was used for the rigid joint formation by alloying with copper interconnection formed on a stress sensing chip. The measured amplitude of the residual stress increased from about 30 MPa to 250 MPa depending on the combination of materials such as bump, underfill, and interconnections. It was confirmed that both the material constant of underfill and the alignment structure of fine bumps are the dominant factors of the local deformation and stress of a silicon chip mounted on area-arrayed metallic bumps. It was also confirmed experimentally that both the hound’s-tooth alignment between a TSV (Through Silicon Via) and a bump and control of mechanical properties of electroplated copper thin films used for the TSV and bump is indispensable in order to minimize the packaging-induced stress in the three-dimensionally mounted chips. This test chip is very effective for evaluating the packaging-process induced stress in 3D stacked chips quantitatively.

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