The quadratic assignment problem (QAP) is very challengeable and interesting problem that can model many real-life problems. In this paper, we will simply discuss the meaning of quadratic assignment problem, solving techniques and we will give a survey of some developments and researches.
A new bounding procedure for the Quadratic Assignment Problem (QAP) is described which extends the Hungarian method for the Linear Assignment Problem (LAP) to QAPs, operating on the four dimensional cost array of the QAP objective function. The QAP is iteratively transformed in a series of equivalent QAPs leading to an increasing sequence of lower bounds… (More)
This paper presents a new branch-and-bound algorithm for solving the Quadratic Assignment Problem (QAP). The algorithm is based on a Dual Procedure (DP) similar to the Hungarian method for solving the Linear Assignment Problem. Our DP solves the QAP in certain cases, i.e., for some small problems (N<7) and for numerous larger problems (7≤N≤16) that arise as… (More)
This paper presents a new method for optimal matching in observational studies based on mixed integer programming. Unlike widely used matching methods based on network algorithms, which attempt to achieve covariate balance by minimizing the total sum of distances between treated units and matched controls, this new method achieves covariate balance… (More)
We have established a simple method of measuring joint motion under physiological conditions. For this purpose we use an ultrasound measuring system employing marker points consisting of miniaturized ultrasound transmitters. This device was tested on a simple biomechanical model, the linkage of the proximal and distal interphalangeal joints. The angles of… (More)
Primary or secondary flexor tendon surgery occasionally leads to damaged flexor pulleys. Insufficient pulley reconstruction causes loss of finger function by bow stringing of the flexor tendon. This paper reviews the anatomy and biomechanics of the flexor pulley system. Different techniques of reconstruction are discussed.
PURPOSE In clinical day-to-day life, grip strength, key pinch, and range of motion (ROM) serve to objectively evaluate treatment outcomes on wrist interventions. The goals of this study were to generate normative values of wrist function including the parameters of grip strength, key pinch, wrist ROM, and Disabilities of the Arm, Shoulder, and Hand (DASH)… (More)
Twenty-six hands in 25 male patients were treated for peace-time explosion injuries of the palmar aspect. All patients were examined after a mean interval of 7 (1-17) years. In order to establish a regional pattern for each injury the palmar surface of the hand was divided in 21 fields. For each field a score depending on the extent of injury was… (More)
The TFCC is a crucial stabilizer of the DRUJ. Based on its superficial and deep fibers, the TFCC guarantees unrestricted pronation and supination which is essential for performing sophisticated tasks. The ability to perform complex movements is of uppermost importance for hand function. Therefore, a functional intact TFCC is a prerequisite in this context.… (More)
Open or closed flexor tendon injuries may be caused by a variety of circumstances. Loss of function based on flexor tendon injuries is quite often missed. Therefore, a precise knowledge of the anatomy, the biomechanical behaviour of tendons and the intrinsic hand muscles enables the clinician to examine flexor tendon injuries adequately. This article… (More)