Loh Jing | University of Sumatera Utara (original) (raw)

Papers by Loh Jing

IEEE Transactions on Parallel and Distributed Systems, 2005

This paper presents the Exchanged Hypercube, a new interconnection network obtained by systematic... more This paper presents the Exchanged Hypercube, a new interconnection network obtained by systematically removing links from a binary hypercube. It maintains several desirable properties of the binary hypercube yet with reduced interconnection complexity. We also introduce the Extended Binomial Tree, a spanning tree of the Exchanged Hypercube that preserves many desirable properties of the original Binomial Tree. A fault-tolerant routing strategy is also proposed for the Exchanged Hypercube.

Journal of Parallel and Distributed Computing, 2007

Wireless sensor networks are inherently plagued by problems of node failure, interference to comm... more Wireless sensor networks are inherently plagued by problems of node failure, interference to communications from environmental noise and energy-limited sensor motes. These problems pose conflicting issues in the design of suitable routing protocols. Several existing reliable routing protocols exploit message broadcast redundancy and hop count as routing metrics and their performance trade-offs are revealed during simulation. In this paper, we study and analyse related design issues in proposed efficient and reliable routing protocols that attempt to achieve reliable and efficient communication performance in both single-and multi-hub sensor networks. Simulation results of four such routing protocols show that routing performance depends more on optimal (near-optimal) routing in single hub than in multi-hub networks. Our work also shows that optimal (near-optimal) routing is better achieved when historical metrics like packet distance traversed and transmission success are also considered in the routing protocol design.

Tensile-strained Ge photodetector is realized on Si-substrate using novel SiSiGe compliant layer ... more Tensile-strained Ge photodetector is realized on Si-substrate using novel SiSiGe compliant layer with two-step Ge-process. Monolithic integration of p-i-n detectors with low dark current (0.4 nA), responsivity (190 mA/W) and high speed (5 GHz) on Ge-CMOS platform is demonstrated, with Ge pMOSFET showing 2X Si hole mobility.

IEEE Electron Device Letters, 2007

ABSTRACT

Board level drop test is one of the key qualification tests to ensure the solder joint reliabilit... more Board level drop test is one of the key qualification tests to ensure the solder joint reliability. It becomes critical due to lead free solder. In this paper, we study the effect of underfills on drop test performance of a fine-pitch ball grid array package (BGA), experimentally and numerically. Failure mode is also compared. There are good correlations between testing and modeling on the effect of underfill on failure modes and failure mechanisms of solder joints. Moreover, the results of testing and modeling show that important parameters affecting drop test performance are position of the package on the board, modulus of the underfill, and, circumstantially, the interfacial fracture toughness of the underfill. An unfilled underfill, as opposed to a silica-filled underfill, can provide satisfactory, or even superior, drop test performance if its interfacial fracture toughness is sufficiently high. The benefit of an unfilled underfill is better processability

Cheminform, 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was e... more ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Tetrahedron Letters, 2000

A new method for the stereoselective synthesis of 1,3-amino alcohols based on the indium-mediated... more A new method for the stereoselective synthesis of 1,3-amino alcohols based on the indium-mediated allylation of keto ester (R,S)-2 in aqueous media, resulting from shielding of one face by a remote substituent, was developed to be a useful method for acyclic stereocontrol in the absence of any obvious steric interaction.

This article presents a cost-effective fault-tolerant routing strategy for optical-electronic gri... more This article presents a cost-effective fault-tolerant routing strategy for optical-electronic grids. We propose the design of a fully adaptive, fault-tolerant routing strategy for multi-hop grid networks using wavelength-division multiplexing. The routing strategy is both deadlock-free and livelock-free. Regardless of the number and type of faults and size of the grid network, only three buffer sets and two routing tables of size O(d) are required at each node, where d is the grid dimension. In the absence of faults, minimal paths with the least congestion are used so that latency is minimised. In the presence of faults or congestion, misrouting is constrained selectively to prevent livelock. The routing strategy is local-information based and does not exploit component redundancy or isolation of healthy nodes and links.