Charles C. Chang

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The debate on the effectiveness of foreign aid has intensified in recent years as aid has come under increasing budgetary pressures in donor countries. Whatever the merits of the opposing arguments, the fundamental issue arises of whether conventionally-used measures of aid such as ODA, that lump together grants and loans, accurately reflect true aid flows.(More)
A reactive navigation system for an autonomous mobile robot in unstructured dynamic environments is presented. The motion of moving obstacles is estimated for robot motion planning and obstacle avoidance. A multisensor-based obstacle predictor is utilized to obtain obstacle-motion information. Sensory data from a CCD camera and multiple ultrasonic range(More)
BACKGROUND CONTEXT Venous hypertensive myelopathy (VHM) results from spinal vascular malformations of arteriovenous shunting that increases spinal venous pressure, leading to congestive edema and neurologic dysfunction. There has been no report of VHM associated with cervical spondylotic myelopathy (CSM). PURPOSE The aim of this study was to report an(More)
UNLABELLED Pulmonary embolism (PE) complicates 1% to 10% of total joint arthroplasties and generally requires immediate anticoagulation. Low-molecular-weight heparins have supplanted unfractionated heparin as the treatment of choice for PE and hold a 1A recommendation from the American College of Chest Physicians for this indication. However, the(More)
The problem of navigating a mobile robot among moving obstacles is usually solved on the condition of knowing the velocity of obstacles. However, it is difficult to provide such information to a robot in real time. In this paper, we present an environment predictor that provides an estimate of future environment configuration by fusing multisensor data in(More)
This paper proposes a simple, yet effective scheme to prevent congestion in a packet-switched multistage interconnection network (MIN) caused by hotspols. In this scheme, switches in the second and third stages of the MIN monitor their buffer occupancy to detect any notable nonuniform access behavior. When a switch detects congestion, packets generated by(More)