bluuebunny/crossref_metadata_2025 huggingface dataset:
Stochastic Hamilton's principle and noisy sliding surfaces in the tracking control of manipulators
Authors: Jumarie Guy
Published: March 2009

In the tracking control of manipulators via the sliding scheme, it may happen that sometimes, because of various inaccuracies, the definition of the actual sliding surface involves errors terms which may be either deterministic or, on the contrary, stochastic. This paper considers this last case and shows how one can estimate the new performances of the system so disturbed. A stochastic Hamilton's principle is applied, by combining the Lagrange parameter technique with results of the dynamic programming approach.
A new representation for a robot grasping quality measure
Authors: Varma Venugopal K. , Tasch Uri
Published: March 2009

When an object is held by a multi-fingered hand, the values of the contact forces can be multivalued. An objective function, when used in conjunction with the frictional and geometric constraints of the grasp, can however, give a unique set of finger force values. The selection of the objective function in determining the finger forces is dependent on the type of grasp required, the material properties of the object, and the limitations of the röbot fingers. In this paper several optimization functions are studied and their merits highlighted. The paper introduces a graphical representation of the finger force values and the objective functions that enable one to select and compare various grasping configurations. The impending motion of the object at different torque and finger force values are determined by observing the normalized coefficient of friction plots.
The method of minimal neighborhood: a new and most effective iterative method for minimum cost trajectory planning in robot manipulators
Authors: Duleba Ignacy
Published: March 2009

In this paper a method of minimal neighborhood for cost optimal trajectory planning along prescribed paths is introduced. The method exploits the phase-plane approach. In the phase-plane, in an iterative procedure, subareas of search are built, called neighborings, which surround the current-best trajectory. In each iteration, in order to find the next-best trajectory, the dynamic programming (pruned to the subarea) is used. The method of minimal neighborhood makes the neighborings as small as possible and therefore speeds up computations maximally. The tests carried out on a model of the IRb-6 ASEA robot have shown that the method of minimal neighborhood is much faster than dynamic programming applied to the whole phase-plane, while preserving the quality of the resulting trajectory.
Wire-frame modelling of polyhedral objects from rangefinder data
Authors: Badcock J. M. , Jarvist R. A.
Published: March 2009

Methods are described for computer analysis of image-data from a coded-stripe rangefinder. The main objective is to find vertex coordinates and connectivity information for a polyhedral object, enabling it to be represented by a wire-frame model. For each of several rangefinder viewpoints, the data is processed to extract three-dimensional edge and vertex positions. The emphasis is on estimation techniques that make good use of fairly sparse data-points. Results from different viewpoints are merged to produce a 3D model of the object.
Coping with joint velocity limits in first-order inverse kinematics algorithms: analysis and real-time implementation
Authors: Chiacchio Pasquale , Chiaverini Stefano
Published: March 2009

A major problem in inverse kinematics algorithms is that the generated joint velocities to be fed to the joint servos may cause violation of the speed limits of the joint actuators. In this paper, it is shown how to properly cope with joint velocity limits in first-order inverse kinematics algorithms; the proposed technique guarantees tracking of the desired end-effector path. This goal is achieved by suitably slowing down the task-space trajectory when joint velocity limits are encountered. The time law is modified through a time warp such that the introduced virtual time allows fulfillment of the velocity constraints. A case study is developed to show the effectiveness of the proposed method and a kinematic control scheme based on the presented technique is implemented to demonstrate feasibility under real-time constraints.
A segmentation algorithm for collision avoidance in telerobotics applications
Authors: Strenn Stephen , Hsia T.C. , Wilhelmsen Karl
Published: March 2009

This paper proposes a new algorithm, known as the Segmentation Algorithm, which provides model-based, real-time, whole-arm collision avoidance for telerobotic applications. The work presented here is an extension and modification of potential field theory. Novel aspects of the algorithm include the application of a hierarchical segmentation technique to minimize on-line processing and the development of procedures which account for workspace object translation, rotation, and grasping. The'SA outputs torques, which, when applied to the control arm, prevent the teleoperator from driving the remote arm into a collision. The teleoperator actually feels workspace objects that are spatially close to the remote arm—an experience known as virtual force-reflection. The SA's performance has been analyzed in terms of its speed and efficiencyvis a visvarious system parameters, including workspace object distribution, size, and number. Simulation results show that the SA succeeds in providing real-time collision avoidance where less elegant brute force algorithms fail.
Inverse kinematics of free-floating space robots with minimum dynamic disturbance
Authors: Xi Fengfeng
Published: March 2009

In this paper a new method is presented for solving the inverse kinematics of free-floating space manipulators. The idea behind the method is to move the space manipulator along a path with minimum dynamic disturbance. The method is proposed to use the manipulator Jacobian instead of the generalized Jacobian of the spacecraft-manipulator system. This is based on the simple fact that, if the space manipulator moves along the so-called Zero Disturbance Path (ZDP), the spacecraft is immovable. As a result, the space manipulator can in this case be treated as a terrestrial fixed-based manipulator. Hence, the motion mapping between the joints and the end-effector can be described directly by the manipulator Jacobian. In the case that the ZDP does not exist, it can be shown that the solutions obtained by the proposed method provide a path with minimum dynamic disturbance.
Comparing two algorithms for automatic planning by robots in stochastic environments
Authors: Christiansen Alan D. , Goldberg Kenneth Y.
Published: March 2009

Planning a sequence of robot actions is especially difficult when the outcome of actions is uncertain, as is inevitable when interacting with the physical environment. In this paper we consider the case of finite state and action spaces where actions can be modeled as Markov transitions. Finding a plan that achieves a desired state with maximum probability is known to be anNP-Completeproblem. We consider two algorithms: an exponential-time algorithm that maximizes probability, and a polynomial-time algorithm that maximizes a lower bound on the probability. As these algorithms trade off plan time for plan quality, we compare their performance on a mechanical system for orienting parts. Our results lead us to identify two properties of stochastic actions that can be used to choose between these planning algorithms for other applications.
A novel approach to flexible robotic assembly systems
Authors: Billatos Samir B.
Published: March 2009

This paper presents a novel approach to designing and manufacturing of a universal gripper to be used with industrial robots in flexible assembly systems. Important issues that impact greatly on the efficiency of the gripper are also discussed in this paper. Such issues include the degree of compliance allowed by the robotic wrist and the way these grippers are actuated. The gripper has been proven to be extremely flexible and low in cost.
A compliant control method for disassembly of non-elastic parts using realised motion
Authors: Denizhan Yagmur
Published: March 2009

In disassembly tasks, due to the large variety of objects and the different positions and orientations in which they appear, the disassembly trajectories supplied on-line by a human operator or an automatic recognition system can contain large errors. The classical compliant control methods turn out to be insufficient to eliminate sticking which is due to these errors. This paper presents a compliant control method for disassembly of non-elastic parts in non-elastic environments which adopts the trajectories according to realised motion. In case of sticking a new direction of motion is searched for until the manipulated part is set into motion.
Telerobotic surgery project for laparoscopy
Authors: Rovetta Alberto , Sala Remo , Wen Xia , Cosmi Francesca , Togno Arianna , Milanesi Santo
Published: March 2009

This paper deals with the first transatlantic experiment of robotic telesurgery. A robot in Milan (Italy) performed an operation on a model of a pig, and the surgeon controller was in JPL, Pasadena (USA). By means of two communication satellites and of an optical fibre network, the robot performed a biopsy and a preliminary cut for a laparoscopic mini-invasive surgery operation.
A contribution to parallelization of symbolic robot models
Authors: Kirćanski N. , Davidović T. , Vukobratović M.
Published: March 2009

This paper is focused on task scheduling in multiprocessor robot controllers. To minimize the input-output time delay our consideration is restricted to parallel architectures that include complete crossbar interconnection networks. In this paper, an efficient scheduling algorithm based on a heuristic function is considered. This function takes into account delays caused by interprocessor communication and minimizes both the execution time and the communication cost. Robot control computation based on a highly efficient customized symbolic method is decomposed into a large number of simple tasks, each involving a single floating-point operation. Starting with an empty partial schedule, each step of the search extends the current partial schedule by adding one of the tasks yet to be scheduled. The heuristic function used in the algorithm actively directs the search for a feasible schedule, i.e. it helps choose the task that extends the current partial schedule. To increase the computational rate we introduced overlapping of computations.
Reexamination of the DCAL controller for rigid link robots
Authors: de Queiroz M. S. , Dawson D. , Burg T.
Published: March 2009

In this paper, we present two DCAL-like (Desired Compensation Adaptation Law) controllers for link position tracking of n-link, rigid, revolute robot manipulators. First, we use a simplified stability analysis to illustrate global asymptotic link position-velocity tracking for a DCAL-like controller withnonlinearfeedback. The proof is simplified by employing a different structure for the nonlinear feedback than that originally proposed and by making use of thenonlineardamping control design tool. We then use thenonlinear dampingtool to show that a DCAL-like controller withlinearfeedback can guarantee semi-global asymptotic link position-velocity tracking. The proposed nonlinear and linear feedback DCAL-like controllers are experimetally tested and compared using the Integrated Motion Inc. 2-link direct drive robot manipulator.
Sensor-based 2-D Potential Panel Method for Robot Motion Planning
Authors: Zhang Yanjun , Valavanis Kimon P.
Published: March 2009

A potential panel method is proposed to solve simultaneously the path planning and collision avoidance problem for a mobile robot operating in an uncertain obstacle filled environment. The problem is solved in three steps: (1) transform the arbitrary shaped obstacles in the 2-D workspace into simple convex polygons; (2) generate a local minima-free potential field on the workspace; (3) generate a streamline from the starting position towards the goal position in the artificial potential field. The computational complexity of the pertinent algorithms justify the applicability of the approach in real-time. Simulation results are included.
Modelling of a single-link flexible manipulator system: theoretical and practical investigations
Authors: Tokhi M. O. , Azad A. K. M.
Published: March 2009

This paper presents theoretical and experimental investigations into modelling a single-link flexible manipulator system. An analytical model of the manipulator, characterised by an infinite number of modes, is developed using the Lagrange's equation and modal expansion method. This is used to develop equivalent time-domain and frequency-domain working models of the system in state-space and transfer function forms respectively. The model parameters are then estimated experimentally using system's measured input/output data. The model thus obtained is validated through experimentation and results including the effect of payload on system characteristics presented and discussed.
A remote center of motion robotic arm for computer assisted surgery
Authors: Eldridge B. , Gruben K. , LaRose D. , Funda J. , Gomory S. , Karidis J. , McVicker G. , Taylor R. , Anderson J.
Published: March 2009

We have designed a robotic arm based on a double parallel four bar linkage to act as an assistant in minimally invasive surgical procedures. The remote center of motion (RCM) geometry of the robot arm kinematically constraints the robot motion such that minimal translation of an instrument held by the robot takes place at the entry portal into the patientApos;s body. In addition to the two rotational degrees of freedom comprising the RCM arm, distal translation and rotation are provided to manoeuver the instrument within the patient's body about an axis coincident with the RCM. An XYZ translation stage located proximal to the RCM arm provides positioning capability to establish the RCM location relative to the patients anatomy. An electronics set capable of controlling the system, as well as performing a series of safety checks to verify correct system operation, has also been designed and constructed. The robot is capable of precise positional motion. Repeatability in the ±10 micron range is demonstrated. The complete robotic system consists of the robot hardware and an IBM PC-AT based servo controller connected via a custom shared memory link to a host IBM PS/2. For laparoscopic applications, the PS/2 includes an image capture board to capture and process video camera images. A camera rotation stage has also been designed for this application. We have successfully demonstrated this system as an assistant in a laparoscopic cholecystectomy. Further applications for this system involving active tissue manipulation are under development.
Modelling and Control of a Flexible Spherical Wrist
Authors: Perdereau Véronique , Ng S. , Wang D.
Published: March 2009

In this paper, a very inexpensive, lightweight and simple wrist mechanism is introduced. This wrist displays nonlinear torsional vibrations. This differs from conventional wrists in that structural flexibility in the mechanism is allowed to occur by design. In this paper, the dynamic equations of this wrist are derived. System identification techniques are then employed to obtain a linearized model. Various control strategies are studied. It is shown that the input-output feedback linearization technique is not feasible for these nonlinear dynamic equations. It is also shown that the use of conventional rigid body PID controllers on this proto-type is inadequate. A tracking controller which compensates for the flexible dynamics of the wrist is implemented with encouraging results. This controller allows the end-effector to be placed at an arbitrary orientation with little vibration. The effect of the controller is to make the wrist appear to have a much higher structural stiffness. The compliant nature of this wrist allows simple force control strategies to be implemented. It is the combination of the wrist with the control algorithm which makes this design viable.
The Track: Technion Robot And Controller Kit
Authors: Bar-On David , Gutman Shaul , Israeli Amos
Published: March 2009

A modular hierarchical model for controlling robots is presented. This model is targeted mainly for research and development; it enables researchers to concentrate on a certain specific task of robotics, while using existing building blocks for the rest of their applications. The presentation begins by discussing the problems with which researchers and engineers of robotics are faced whenever trying to use existing commercial robots. Based on this discussion we propose a new general model for robot control to be referred as TERM (TEchnion Robotic Model). The viability of the new model is demonstrated by implementing a general purpose robot controller.
A unified approach to the inverse kinematic solution for a redundant manipulator
Authors: Won J. H. , Choi B. W. , Chung M. J.
Published: March 2009

For a kinematically redundant manipulator, some performance indices can be optimized while carrying out a given task. So far, the redundancy resolution has been solved at the joint angle level, the joint velocity level, or joint acceleration level depending on the performance indices. According to the resolution level, the solution is represented by high-order differential equations or superfluous number of equations. We propose a unified approach to the inverse kinematic solution which optimizes it at the joint velocity level regardless of the types of the performance indices. A unified approach to obtain an optimal joint velocity is derived by using the necessary condition for optimality so that the proposed method provides an optimal solution for any performance indices and tasks. The optimal solution becomes a set of the minimum number of first-order differential equations which requires a minimum search dimension.To show the validity of the approach, it is applied to a three-link planar manipulator for various types of performance indices.
Clinical evaluation of the ‘MASTER’ robot system and development of a new version
Authors: Cammoun R. , Détriché J. M. , Lauture F. , Lesigne B.
Published: March 2009

This paper describes the first prototype of the robot system ‘MASTER’ for helping disabled people. The results of evaluations after one year of experiments in French rehabilitation centres are reported. Following comments and criticisms by staff and users, many improvements were made to the first version and have been taken into account in the design of a new version which will be evaluated in 1992–93 in French and European projects.
Conceptual design and dynamics modeling of a cooperative dual-arm cam-lock manipulator
Authors: Meghdari Ali
Published: March 2009

This paper presents the conceptual designs, kinematics and dynamics modeling of a cooperative re-configurable Dual-Arm Cam-Lock Manipulator. A cam-lock manipulator is a robotics structure with a pair of multi-degree of freedom planar arms jointed together at a shared base. This manipulator is designed to be capable of performing a wide variety of tasks by automatically re-configuring itself to form a variable geometry, stiffness, damping, and workspace robotics structure by the virtue of a novel link/joint design along i''s arms, labeled as the cam-lock design. The kinematics and dynamics of this manipulator is described using admissible variables (i.e., variables that define the constrained admissible motion). Along with the dynamic relations of this manipulator, a generic equation was also developed for the joint servo system.
Parameter identification of a semi-flexible kinematic model for serial manipulators
Authors: Gourdeau Richard , Cloutier Guy M. , Laflamme Joseph
Published: March 2009

Structural and control flexibilities affect the absolute precision of serial manipulators. A semi-flexible kinematic model is developed, to improve the absolute static precision. It expands the solid body model by incorporating a spring effect for each joint and a beam effect for each link. The identifiability of the added parameters and the effect of measurement noise are explored on a R4 robot. It requires efforts and pose errors to be known in the tool frame only. Simulation results show that identification of some of the parameters is sensitive to measurement noise on forces and pose. In fact, joint flexibility displacement and beam flexion that occur in the same plane are difficult to dissociate in noisy condition. However, a subset of the original parameters can be defined leading to a model that can be more accurately identified when measurement noise is present. In simulation, precompensation is used in an inverse semi-flexible model that results in a 98% decrease of pose error compared to the rigid body inverse geometric model.
A fast algorithm for distance calculation between convex objects using the optimization approach
Authors: Zeghloul SaÏd , Rambeaud Patrick
Published: March 2009

This paper describes an efficient and fast algorithm for finding the minimum distance between two convex polyhedrons in a three dimensional space. To obtain the minimal distance, the proposed computational scheme is based on a direct approach to minimizing the distance function which produces a succession of optimal search directions along object boundaries. This algorithm combines the gradient projection method'; and an additional optimal search direction when the gradient projection method leads to a zigzagging phenomenon. In this case, the additional optimal search direction accelerates significantly the convergence of the process. Extensive numerical experiments with convex polyhedra show the performance of this algorithm when compared with that of previous approaches. The proposed algorithm may be very helpful in solving the computation of minimal distance between a pair of convex sets, the collision detection problem or to track the closest points of moving convex objects.
Generation of adjacent configurations for a collision-free path planning of manipulators
Authors: Ceccarelli Marco , Valero Francisco , Mata Vicente , Cuadrado† Ignacio
Published: March 2009

In this paper an algorithm is proposed for the problem of path planning of redundant manipulators among obstacles by using a suitable formulation for robot configurations and path strategy. In particular robotic manipulators have been modelled by using reference points on the kinematic chain and their Cartesian coordinates description. The path planning has been formulated as an optimization problem for the determination of adjacent configurations and the path among obstacles with minimum manipulator displacement. The fully Cartesian coordinates description has been useful for the economy of the numerical procedure and for the constraints formulation of link interference and obstacles avoidance constraints. Some examples are reported which prove the practical feasibility of the path planning procedure, and the numerical results have been tested as applicable to industrial robots through easy programming because of the concept of adjacent configurations.
Dynamic model of a two-trailer articulated vehicle subject to nonholonomic constraints
Authors: Bolzern P. , DeSantis R. , Locatelli A. , Togno S.
Published: March 2009

The dynamic model of an articulated vehicle consisting of one tractor and two semi-trailers is derived according to a systematic approach available in the literature. The model is produced on the assumption of no slippage, which enforces nonholonomic constraints. The resulting equations encompass a number of significant special cases.
Introduction to the special issue: microrobots and distributed microactuators in Japan
Authors: Esashi Masayoshi
Published: March 2009

This special issue in Robotica contains papers from Japanese authors on microrobots and distributed microactuators. Advances in technology made possible progress in the realm of small but complicated microsystems that include different elements, such as sensors, circuits and actuators. Microsystems are also called micromachines or microelectromechanical systems (MEMS); microsystems which move like insects are termed microrobots.
‘English fever’ in South Korea: its history and symptoms
Authors: Park Jin-Kyu
Published: March 2009

‘Education fever’ drives the demand for English in South Korea today. One professor of politics has recently deplored the current pursuit of ‘English education’ (yeongeokyoyuk) in South Korea as a ‘collective neurosis of English fever’ (Y-M. Kim, 2002). What has brought this current English boom to South Korea? It can be traced back to the traditional ‘education fever’ (kyoyukyeol) or ‘preoccupation with education’ (Seth, 2002). The English boom resulting from the Korean education fever has led to a strong antipathy toward Koreans – even in English-speaking countries.

This article explains how the current English boom in South Korea has been founded on the long tradition of education fever in the country, and why more and more Korean children are sent abroad to learn the English language. In addition, I also attempt to show the connection between this English boom and an associated antipathy toward the Korean language and Korean speakers in English-speaking countries.
Medical Technology and Health Services in South Korea
Authors: Cho Byong-Hee
Published: March 2009

This article chronicles the adoption of medical technology in twentieth-century Korea. The author suggests that the structure of the present health care delivery system has relied predominantly on small clinic practice and has resulted in a shortage of highly capitalized hospitals and a maldistribution of modern technology. In addition, the author argues that medical practice in small unconnected clinics and hospitals isolate physicians from academic medicine and hamper research. Finally, the highly decentralized structure of Korean medicine is a weak basis for controlling the diffusion of medical technology and leaves most acquisition judgments in the hands of individual hospital owners.
Technology in France
Authors: Lacronique J. F.
Published: March 2009

The author describes how France has attempted to reconcile its ethos of optimum health care for all with a belief in free enterprise, with increasing medical costs and complex technological innovations, and with a traditional distrust of widespread regulation. Effective oversight of the diffusion of technology is further hampered by the shared responsibilities of several government agencies. Although France has enacted a fee schedule for physicians, created national procedures for evaluating equipment, and exercised some control over hospitals, the general sentiment is anti-bureaucratic and third-party insurers will most likely play an important role in limiting the diffusion of technology in the future.
Economic Forces and Hospital Technology
Authors: Buxton Martin J.
Published: March 2009

The paper considers the economic characteristics of technology and suggests a categorization based on the economic nature of particular technologies and their effect on the product health care that may be helpful in considering the economics of technology in hospitals.

It reviews the range of economic forces that might be expected to apply to the use of technology in the hospital setting, and notes some of the evidence to support such hypotheses. In considering the limited evidence from the United Kingdom and elsewhere in Europe, the paper contrasts its focus on socio-political, institutional, and organizational factors, rather than the direct economic factors considered in the United States work.

It suggests that the multiplicity of forces at work make cross-national, empirical, and policy analyses very difficult. Indeed, without more economic appraisal the effect of differences in technology adoption cannot be evaluated.
Smart Instruments, Microprocessors, Personal Computers
Authors: Eden Murray
Published: March 2009

This discussion of Emerging Technology focuses on technological currents in electronic technology rather than in medical technologyper se. The influence of the former on the latter is not merely that medical devices have electronic parts, but that the development of new circuit technology can change radically the design, utility, and even the function of the medical devices.
Framework for Considering the Role of Data Bases in Technology Assessment
Authors: Moses Lincon E.
Published: March 2009

The use of large data bases in technology assessment offers a number of attractive possibilities for the future. This article outlines the major approaches to technology assessment and how data bases can be used to enhance each approach.
What Do Mortality Studies Reveal about Hospital Volume, Teaching Status, And Ownership?
Authors: Kelly Joyce V.
Published: March 2009

Numerous recent studies use risk-adjusted patient mortality rates to measure hospital performance, focusing on such hospital characteristics as volume of patients, teaching status, and ownership. This article summarizes the empirical findings of these studies, critiques their methods and models, and offers recommendations for overcoming several obstacles to meaningful correlation of patient outcomes and provider performance.
Peaks and Pits of Using Large Data Bases to Measure Quality of Care
Authors: Flood Ann Barry
Published: March 2009

This review of the advantages (peaks) and problems (pits) of large data bases to study quality contrasts their suitability with randomized control trials. Researchers need to advise policymakers and others about whenstatisticallysignificant differences in quality are alsopoliticallyandsociallysignificant and deserve responsible reactions.
Using Administrative Diagnostic Data to Assess the Quality of Hospital Care: Pitfalls and Potential of ICD-9-CM
Authors: Iezzoni Lisa I.
Published: March 2009

Diagnostic information within administrative data bases is generally in the form of lnternational Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes. The purpose of this article is to introduce ICD-9-CM, to review its strengths and limitations, and to suggest ways that it can be used through administrative files for assessing the quality of hospital care.
Assessment of Medical Outcomes: New Opportunities for Achieving a Long Sought-After Objective
Authors: Schwart J. Sanford , Lurie Nicole
Published: March 2009

Health outcome assessment may be used for a variety of purposes: to evaluate the effectiveness of medical practices: to assess the quality of services provided; to educate providers, purchasers, and users of health services about the sequelae of treated and untreated disease; to guide reimbursement and regulatory policy; and to characterize the health status of a population. This article focuses on the use of health outcomes to evaluate the effectiveness of medical practices and to assess the quality of services provided.
Searching for Consensus Through Multicriteria Decision Analysis
Authors: Gales Catherine Le , Moatti Jean-Paul
Published: March 2009

Until now, no systematic strategy for the prevention of major hemoglobinopathies has been implemented in southeastern France, in spite of frequencies of β-thalassemia trait and HbS trait as high as 2·5–8% in some ethnic populations. The purpose of the study was to help a group of experts, brought together by the Regional Center for Disease Control, to reach a consensus about screening for carriers of heterozygote hemoglobinopathies. A multicriteria decision-analysis model was used to take into account not only the costs and effectiveness of potential screening strategies, but also five other qualitative criteria: technical and practical feasibilities, ethical acceptability, information follow-up in time, and global impact on health education. Conclusions differ significatively from those of a pure costeffectiveness analysis, but a multicriteria approach seems best suited to medical experts' preferences.
Social and Health Policy Issues in Total Joint Replacement Surgery
Authors: Liang Matthew H. , Wade John , Hartley Robert M. , Cullen Karen E. , Caplan Arthur L.
Published: March 2009

Total joint replacement has restored function and provided comfort to many patients who would otherwise have suffered. However, success and widespread diffusion of this procedure pose a number of important questions. The patient's and the doctor's criteria of success may not be the same: Which are to be used? Health resources are becoming limited: Should money be spent to restore function and for pain relief to those late in life or past their work life? Who makes this choice? A medical technology is tested in the best of settings but routinely practiced in many: How should society and health care professionals monitor the results of surgery? Who should do surgery and where should it be done?
The Adoption and Use of Extracorporeal Shock Wave Lithotripsy by Hospitals in the United States
Authors: Power Elaine J.
Published: March 2009

Extracorporeal shock wave lithotripsy (ESWL) for upper urinary stones has been in use in the United States since 1984. It was accepted immediately by hospitals and physicians, and its diffusion has been and continues to be rapid. Government payment and planning policies do not seem to have slowed this diffusion, although they have had some effect on the ownership of lithotripters and the manner in which ESWL is provided. An unintended but foreseeable result of ESWL's popularity with hospitals, physicians, and patients is that ESWL is not only rapidly replacing traditional surgery but is being used on many patients who would not have had surgery. It is likely that many more upper urinary stones are being treated aggressively now than before ESWL was introduced.
Impact of Extracorporeal Lithotripsy on Patient Management
Authors: Carlsson Per , Jönsson Bengt , Tiselius Hans-Göran
Published: March 2009

Sweden's first, and so far only, ESWL unit for kidney stone treatment became operational on April 1, 1985. This paper presents some intermediate results from an integrated medical, economic, and technical evaluation of the new technology. Seventy-eight percent of 477 patients were defined as successfully treated, totally stone free or fragments less than 4 mm in size, after a follow-up of four weeks. After six months, the share of successfully treated patients had increased to 82%. Successes were closely related to the stone situation; the smaller the stone, the greater success of treatment. Patients' experiences with treatment were also studied and showed that less than 5% of the patients perceived the treatment as unpleasant, frightening, and/or time consuming. Epidemiological data reveal that one unit can replace all open surgical operations on the kidney.
Magnetic Resonance Imaging
Authors: Persson Bertil R. R.
Published: March 2009

The first successful demonstration of the phenomenon of nuclear magnetic resonance (NMR), or nuclear induction in solids and liquids, was published almost simultaneously in 1946 by Bloch, Hansen, and Packard (7) working at Stanford University and Purcell, Torrey, and Pound (75) working at Harvard University. The immediate impact of their work was in physics and chemistry, but the applications have steadily widened and recently the application of NMR in medicine has become very exciting.
Health Services for Pregnancy in Europe
Authors: Wagner Marsden G.
Published: March 2009

In 1979, maternal and child health issues were discussed during the annual meeting of the 33 Member States of the European Region of the World Health Organization. During this discussion many countries expressed concern about the services offered for pregnancy, birth and the period following birth. The countries recognized that, as yet, unsolved problems remain which must be examined and they asked the European Regional Office of WHO to mount activities to study and report on these problems surrounding birth and birth care. In response to this request, the maternal and child health unit of the European Regional Office organized a Perinatal Study Group. The Group's 15 members came from 10 countries and spanned 10 professional disciplines: economics, epidemiology, health administration, midwifery, nursing, obstetrics, pediatrics, psychology, sociology, and statistics. For five years the Group conducted surveys, reviewed the literature and brought its own personal and professional experience to discussions of the health services for women and their babies, during pregnancy and birth, and after birth. The entire group met together at least once a year, at which time findings from the previous year's work were presented, followed by lengthy, sometimes heated, open and free discussions.
Perinatal Health and Regional Activities of the Latin-American Center For Perinatology and Human Development
Authors: Schwarcz Ricardo
Published: March 2009

Latin America and the Caribbean had about 370 million inhabitants in 1980 (8), and about 10 million births occurred in this population that year. Even if, as expected, the birth rate drops 14% between 1980 and the year 2000, the population exposed to reproductive risks would still increase by 26%, because Latin America's population is expected to rise to 600 million by the year 2000 (17). Thirteen million births are expected in the year 2000.
Health Education by Professionals During Pregnancy: Assessing Needs and Effectiveness
Authors: Banta H. David , Houd Susanne
Published: March 2009

Pregnancy care is undergoing an evolution. The trend toward professional control and technological intervention begun decades ago is under challenge by some women's groups and health professionals, who seek to make the pregnant woman herself the locus of control. In the same period, a developing literature concerning the relation of health to psychological and social factors has demonstrated their importance (3) and raised the issue of the place of social support and social action in health care (24).
Semen Banking and Artificial Insemination by Donor in France: Social and Medical Discourse
Authors: Novaes Simone B.
Published: March 2009

Artificial insemination with donor semen (AID) has recently come into public view—particularly in France—because of its association with a newer technique, the cryopreservation of semen. One of the oldest and simplest of reproductive techniques, used most frequently as a means of compensating for male infertility, artificial insemination was previously confined to the private clinician's office, where maximum confidentiality could be ensured. This shielded all of the parties involved—recipients, donor, and physician—from moral reprobation and the possible legal complications arising from the use of donor sperm. However, in the mid-twentieth century, some physicians and researchers in cyrogenics came up with the idea that the freezing and stocking of donor semen in banks might greatly improve the psychological conditions and facilitate the material arrangements for performing AID. Essentially, the donor's availability would no longer have to coincide with the woman's ovulation, meaning less inconvenience for the donor, more time for screening his medical history and running the necessary tests on his semen, and possibly a certain tempering of AID's adulterous connotations. Although results with frozen semen were not as satisfactory as with fresh (the probability of a pregnancy at any cycle is almost twice as great with fresh semen), the material and psychological benefits were considered greatly to outweigh the lesser efficiency of frozen sperm.
Assessing the Artificial Heart: The Clinical Moratorium Revisited
Authors: Swazey Judith P. , Watkins Judith C. , Fox Renée C.
Published: March 2009

Viewed in relation to the vast amount of clinical research in the United States, the number of total artificial heart (TAH) implants is so small as to be statistically invisible. And while the results of those implants to date may seem dubious in terms of the recipients' outcomes, theyare in fact very similar to those of many other innovative therapies when they are first tried ondesperately ill patients. Why, then, has the artificial heart been the object and subject of suchextraordinary interest and controversy? It has been the subject of special federal studies, reports, and hearings for 20 years; has been perceived and portrayed as a unique chapter in the annals of human experimentation and therapeutic innovation; has attracted medically unprecedented media attention; and, in the case of permanent implants, has received unusually exhaustive and restrictive regulatory supervision.
HLA-Matched Donor Registries for Bone Marrow Transplants: A Decision Analysis
Authors: Eckman Mark H. , Sonnenberg Frank A. , Jacoby Itzhak , Pauker Stephen G.
Published: March 2009

Bone marrow transplantation has become an accepted treatment for severe aplastic anemia, acute myelogenous leukemia, and acute lymphocytic leukemia (20;35). Less commonly thalassemia (23), multiple myeloma (25), severe combined immune deficiencies (10), and chronic granulocytic leukemia (14) are also treated with marrow transplantation. Most donors are siblings whose HLA phenotype is identical to the patient's. Such donors, however, are available to only one third of patients (6;16;27;28;35). In the absence of an HLA-identical sibling, partially matched, haplo-identical, related donors (differing by only one major histocom-patibility antigen) can be found for another 7% of patients (1;6;27;37). A variety of lower quality matches also can be found but have not been used extensively. Advances in tissue typing and the treatment of graft versus host disease now allow physicians to consider matchedunrelatedindividuals as potential donors when a suitable related donor is not available (11;12;13;15;17;22).
Quality of Life: Organ Transplantation and Artificial Organs
Authors: Christopherson Lois K.
Published: March 2009

This article describes issues that are clinically significant when assessing quality of life of patients whose organ disease can be treated only through transplantation or reliance upon an artificial organ. Emphasis is placed on stresses that affect the family as well as the immediate patient, because, over time, these are inextricably interwoven. The transplant recipient who experiences a “good” medical outcome may perceive that he has little to live for if his family is severely disrupted or broken apart by the strain of the illness. The family of a patient who dies after unremitting complications while being sustained by an artificial organ may experience both relief at the lifting of an unmanageable burden, and continuing guilt that they were unable to provide unconditional love and support to a dying family member.
Economic Evaluation of Medical Technologies
Authors: Hutton John
Published: March 2009

Economic techniques have been used for several years to evaluate health care expenditures, and there is reasonable agreement amongst economists as to the appropriate methodology. Comprehensive reviews of techniques and applications can be found in Drummond (3,4), Culyer and Horisberger (2) and a report from the Office of Technology Assessment (7). More recently Williams (13) has addressed the problems of evaluating a developing technology and Wagner (10) the specific problems of diagnostic technologies.
Toward Quality Assurance in QALY Calculations
Authors: Nord Erik
Published: March 2009

The utility weights that are used in published scientific articles for assessing benefits in terms of quality adjusted life-years gained often have a weak theoretical and empirical basis. To a large extent, the weights seem to be used without critical thought and sensible discussion. In a majority of cases, the sensitivity of the results to the weights that have been chosen is not demonstrated, and readers are not provided with information in a way that facilitates independent calculations. This paper calls for a standard for future publications.
Defusing Technology:Technology Diffusion in British Columbia
Authors: Kazanjian Arminée , Friesen Kathryn
Published: March 2009

In order to explore the diffusion of the selected technologies in one Canadian province (British Columbia), two administrative data sets were analyzed. The data included over 40 million payment records for each fiscal year on medical services provided to British Columbia residents (2,968,769 in 1988) and information on physical facilities, services, and personnel from 138 hospitals in the province. Three specific time periods were examined in each data set, starting with 1979–80 and ending with the most current data available at the time. The detailed retrospective analysis of laboratory and imaging technologies provides historical data in three areas of interest: (a) patterns of diffusion and volume of utilization, (b) institutional profile, and (c) provider profile. The framework for the analysis focused, where possible, on the examination of determinants of diffusion that may be amenable to policy influence.
Transferring Technology Among Nations: A View of the Process in the Middle East
Authors: Basques Eric
Published: March 2009

During the last 12 years, most Middle Eastern countries, particularly those focused upon in this study (Algeria, Egypt, prerevolutionary Iran, Iraq, Kuwait, and Saudi Arabia), have placed increasing emphasis on improved health care. This emphasis has been reflected in both budgetary and public policy plans. The strides made in medical care during this period have been enormous, but much remains to be done. Some of the major health problems today involve diseases that have largely been conquered in industrialized countries, such as infectious and parasitic diseases, respiratory infections, problems related to childbirth, and diarrheal disease. Chronic diseases, such as heart disease, which have become common in industrialized countries and to which much of the newer medical technology is addressed, are, by many accounts, far down on the list of health problems in the Middle East. Many Middle Eastern countries need comprehensive public health programs to help meet their goals.
Assessment of Drugs in Sweden
Authors: Westerholm Barbro
Published: March 2009

The assessment of drugs in Sweden has a long tradition that goes back to the seventeenth century when the Collegium Medicorum was established in 1663. One of its duties was to control the production of drugs in pharmacies. In 1688, Sweden got its first pharmacopoeia. In 1917, the Pharmaceutical Laboratory was founded as an advisory body of the National Board of Health and Welfare. The laboratory, now called the Department of Drugs, became responsible for evaluating drug applications, including information on their pharmaceutical and chemical properties, pharmacological actions, and clinical effects.
Commentary
Authors: Barnard David
Published: March 2009

Of the many ways to conceptualize the relationship between modern medicine and moral principles, by far the most reassuring is the idea that technically good and morally good medical care are one and the same. There are no contradictions, in other words, between the claims of moral obligation and the canons of scientific medical practice. In a trivial sense, this is undoubtedly correct. It is immoral to profess medical competence that one does not have. Ethical medicine presupposes technical knowledge and skill. But what of the far stronger proposition that authentic technical competence inevitably generates ethical practice? As might be expected in complicated human affairs, this statement is only partially true.
Orthopedic Technology for the Elderly
Authors: Bauer Göran C. H.
Published: March 2009

The termorthopedicswas introduced in 1741 by Nicolas André in Paris for “the Art of Prevention and Correction of Deformities in Children” and for 200 years orthopedic institutions were mainly concerned with locomotor problems in children and young adults. After World War II, however, the majority of orthopedic patients were not children. Devas (6) has coined the expression “geriatric orthopedics”, a semantic contradiction which highlights that we now face an increasing volume of elderly patients in whom the locomotor system causes severe problems. For example, in my own institution an orthopedic wing built in 1928 contained 135 beds, the majority of which were occupied by children. Today 10 beds suffice for our orthopedic children. Half of all orthopedic beds in Sweden are used for hip surgery in the very old.