scispace - formally typeset
Search or ask a question
Author

Peter C. Y. Chen

Other affiliations: Singapore–MIT alliance
Bio: Peter C. Y. Chen is an academic researcher from National University of Singapore. The author has contributed to research in topics: Heat sink & Micro heat exchanger. The author has an hindex of 17, co-authored 94 publications receiving 2200 citations. Previous affiliations of Peter C. Y. Chen include Singapore–MIT alliance.


Papers
More filters
Journal ArticleDOI
Zheng Zhao1, Weihai Chen1, Xingming Wu1, Peter C. Y. Chen, Jingmeng Liu1 
TL;DR: A novel traffic forecast model based on long short-term memory (LSTM) network is proposed, which considers temporal-spatial correlation in traffic system via a two-dimensional network which is composed of many memory units.
Abstract: Short-term traffic forecast is one of the essential issues in intelligent transportation system. Accurate forecast result enables commuters make appropriate travel modes, travel routes, and departure time, which is meaningful in traffic management. To promote the forecast accuracy, a feasible way is to develop a more effective approach for traffic data analysis. The availability of abundant traffic data and computation power emerge in recent years, which motivates us to improve the accuracy of short-term traffic forecast via deep learning approaches. A novel traffic forecast model based on long short-term memory (LSTM) network is proposed. Different from conventional forecast models, the proposed LSTM network considers temporal-spatial correlation in traffic system via a two-dimensional network which is composed of many memory units. A comparison with other representative forecast models validates that the proposed LSTM network can achieve a better performance.

1,204 citations

Journal ArticleDOI
TL;DR: This work reports on a novel spiral microfluidic device with a trapezoidal cross-section for ultra-fast, label-free enrichment of CTCs from clinically relevant blood volumes, using the inherent Dean vortex flows present in curvilinear microchannels under continuous flow.
Abstract: The enumeration and characterization of circulating tumor cells (CTCs), found in the peripheral blood of cancer patients, provide a potentially accessible source for cancer diagnosis and prognosis. This work reports on a novel spiral microfluidic device with a trapezoidal cross-section for ultra-fast, label-free enrichment of CTCs from clinically relevant blood volumes. The technique utilizes the inherent Dean vortex flows present in curvilinear microchannels under continuous flow, along with inertial lift forces which focus larger CTCs against the inner wall. Using a trapezoidal cross-section as opposed to a traditional rectangular cross-section, the position of the Dean vortex core can be altered to achieve separation. Smaller hematologic components are trapped in the Dean vortices skewed towards the outer channel walls and eventually removed at the outer outlet, while the larger CTCs equilibrate near the inner channel wall and are collected from the inner outlet. By using a single spiral microchannel with one inlet and two outlets, we have successfully isolated and recovered more than 80% of the tested cancer cell line cells (MCF-7, T24 and MDA-MB-231) spiked in 7.5 mL of blood within 8 min with extremely high purity (400–680 WBCs mL−1; ∼4 log depletion of WBCs). Putative CTCs were detected and isolated from 100% of the patient samples (n = 10) with advanced stage metastatic breast and lung cancer using standard biomarkers (CK, CD45 and DAPI) with the frequencies ranging from 3–125 CTCs mL−1. We expect this simple and elegant approach can surmount the shortcomings of traditional affinity-based CTC isolation techniques as well as enable fundamental studies on CTCs to guide treatment and enhance patient care.

518 citations

Journal ArticleDOI
TL;DR: A novel spiral microchannel with a trapezoidal cross-section that generates stronger Dean vortices at the outer half of the channel and shows that particles focusing in such device are sensitive to particle size and flow rate, and a higher separation resolution is achieved over conventional spiral microchannels with rectangular cross- section.
Abstract: The paper reports a new method for three-dimensional observation of the location of focused particle streams along both the depth and width of the channel cross-section in spiral inertial microfluidic systems. The results confirm that particles are focused near the top and bottom walls of the microchannel cross-section, revealing clear insights on the focusing and separation mechanism. Based on this detailed understanding of the force balance, we introduce a novel spiral microchannel with a trapezoidal cross-section that generates stronger Dean vortices at the outer half of the channel. Experiments show that particles focusing in such device are sensitive to particle size and flow rate, and exhibits a sharp transition from the inner half to the outer half equilibrium positions at a size-dependent critical flow rate. As particle equilibration positions are well segregated based on different focusing mechanisms, a higher separation resolution is achieved over conventional spiral microchannels with rectangular cross-section.

246 citations

Journal ArticleDOI
Zhe Lu1, Peter C. Y. Chen1, Joohoo Nam1, Ruowen Ge1, Wei Lin 
TL;DR: The experimental results demonstrate that the technique of position control with dynamic penetration-force feedback is practicable for automatic batch microinjection applications.
Abstract: In this paper, we report the development of a prototype micromanipulation system for automatic batch microinjection of zebrafish embryos. Such automatic batch processing is made possible by (i) the development of a machine vision algorithm to identify the number of embryos in a batch and to locate the centerline of each embryo, (ii) the integration of a piezoresistive micro-force sensor with a micropipette to measure the penetration force of the embryo in real time and (iii) the synthesis of a position control with dynamic force feedback by exploiting the characteristics of the force profile associated with the microinjection process. The effectiveness of this prototype micromanipulation system has been demonstrated in an experiment. The experimental results demonstrate that the technique of position control with dynamic penetration-force feedback is practicable for automatic batch microinjection applications.

126 citations

Journal ArticleDOI
01 Nov 2006
TL;DR: Critical issues and their available solutions related to force control in micromanipulation are surveyed, including techniques for dealing with adhesion forces and methods for force sensing and control.
Abstract: In micromanipulation, the size of the manipulated object is usually much less than 1 mm in a single dimension, in which case gravitational and inertial forces are no longer dominant. This leads to problems (for manipulation through force) that are not evident in the macroworld, and for which the macroworld techniques alone may not be adequate to provide solutions. This paper surveys critical issues and their available solutions related to force control in micromanipulation. It focuses on: 1) techniques for dealing with adhesion forces and 2) methods for force sensing and control

98 citations


Cited by
More filters
Journal ArticleDOI

[...]

08 Dec 2001-BMJ
TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

33,785 citations

Posted Content
TL;DR: This paper proposes gradient descent algorithms for a class of utility functions which encode optimal coverage and sensing policies which are adaptive, distributed, asynchronous, and verifiably correct.
Abstract: This paper presents control and coordination algorithms for groups of vehicles. The focus is on autonomous vehicle networks performing distributed sensing tasks where each vehicle plays the role of a mobile tunable sensor. The paper proposes gradient descent algorithms for a class of utility functions which encode optimal coverage and sensing policies. The resulting closed-loop behavior is adaptive, distributed, asynchronous, and verifiably correct.

2,198 citations

Journal ArticleDOI
TL;DR: This review examines the breadth of microfluidic cell sorting technologies, while focusing on those that offer the greatest potential for translation into clinical and industrial practice and that offer multiple, useful functions.
Abstract: Accurate and high throughput cell sorting is a critical enabling technology in molecular and cellular biology, biotechnology, and medicine While conventional methods can provide high efficiency sorting in short timescales, advances in microfluidics have enabled the realization of miniaturized devices offering similar capabilities that exploit a variety of physical principles We classify these technologies as either active or passive Active systems generally use external fields (eg, acoustic, electric, magnetic, and optical) to impose forces to displace cells for sorting, whereas passive systems use inertial forces, filters, and adhesion mechanisms to purify cell populations Cell sorting on microchips provides numerous advantages over conventional methods by reducing the size of necessary equipment, eliminating potentially biohazardous aerosols, and simplifying the complex protocols commonly associated with cell sorting Additionally, microchip devices are well suited for parallelization, enabling complete lab-on-a-chip devices for cellular isolation, analysis, and experimental processing In this review, we examine the breadth of microfluidic cell sorting technologies, while focusing on those that offer the greatest potential for translation into clinical and industrial practice and that offer multiple, useful functions We organize these sorting technologies by the type of cell preparation required (ie, fluorescent label-based sorting, bead-based sorting, and label-free sorting) as well as by the physical principles underlying each sorting mechanism

845 citations