Minimum effort factor approach for sensor-based control of a four-joint 6-dof redundant manipulator

A sensor-driven control model and a minimum effort control algorithm in terms of time and energy expended during the execution of a movement strategy are described and validated for a multijointed cooperating robotic manipulator. Considering smooth, human-like (anthropomorphic) movements, using joint motion profiles achievable in real time as well as sensory information from all joints, and evaluating the total work expended by each manipulator joint during the execution of a movement strategy, a minimum effort motion trajectory is synthesized to precisely and efficiently position the robotic arm end-effector. This sensor-based approach significantly reduces the computational requirements for such cooperative motion. The minimum effort control algorithm generates several human-like arm movement strategies and selects the best strategy on the basis of expendable effort. The algorithm has an inherent basis to deal with obstacles in an efficient way. Detailed examples are described from the simulation studies. © 1994 John Wiley & Sons, Inc.     

Multilevel optimization applied to hull girder design using three panel forms

A multilevel design scheme for ship's hull girders (longitudinal members between two adjacent transverse frames) is presented in this paper. This design scheme handles, very conveniently, the complexity of using an optimization algorithm for such complex design problems having a large number of design variables, nonlinear constraints dealing with different failure modes and interactions among substructures, and nonlinear design objectives. The conventional multilevel design technique is modified by introducing an approach called constraint coordination to increase the probability of achieving the overall optimum very efficiently.The scheme is demonstrated by application to the structural design of hull girders with simple structural modelling to represent inland waterway ships on which there was a special emphasis in the original research project (Rahman 1991). Three possible panel (consisting of one stiffener and its attached plating) forms; tee stiffened, flat-bar stiffened and corrugated, are optimized to synthesize the hull girder in order to achieve the most efficient structure. The effect of price-structure (labour rate to material price ratio) on the design is also investigated.     

Problem of accounting for the deformations of buildings subject to construction in areas adjacent to them

Characteristic features of the development of additional deformations of buildings constructed on inhomogeneous beds during construction performed on neighboring areas are addressed. The significant role of the mutual effect of buildings is exposed, and one possible approach to determination of additional deformations, which is based on the use of the finite-element method, is proposed. Saint Peterburg State Technical University. Scientific-Research Institute of Industrial Construction. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 1, pp. 7–9, January–February, 1994.     

Staurosporine and its derivatives enhance f-Met-Leu-Phe-induced superoxide production via phospholipase D activation in human polymorphonuclear leukocytes

Staurosporine (STAR) is one of the most potent inhibitors of protein kinase C (PKC). It is known that in human polymorphonuclear leukocytes (PMNs), the phorbol ester-induced generation of superoxide anion (respiratory burst) is effectively inhibited by STAR in a dose-dependent manner, whereas superoxide generation induced by chemoattractants, e.g. n-formyl-methionyl-leucyl-phenylalanine (FMLP) or PAF, is regulated biphasically by STAR. We compared the effects of STAR and K252a on FMLP-induced superoxide production from PMNs and examined the effects of propranolol, a inhibitor of phosphatidic acid (PA) phosphohydrolase, on the potentiation of the production by STAR. We also examined the effects of some derivatives of STAR and K252a on the production and the alteration of the effects induced by propranolol pretreatment. When PMNs were stimulated with FMLP, STAR potentiated superoxide production by 240.5 +/- 30.9% at a low concentration (100 nmol/l). Propranolol pretreatment specifically inhibited the potentiation. When phorbol-12-myristate-13-acetate (PMA) was used as a stimulant, STAR inhibited superoxide production dose-dependently and did not enhance the production. K252a inhibited PMA or FMLP-induced superoxide production dose-dependently and did not enhance FMLP-induced superoxide production. STAR derivatives showed potentiation of FMLP-induced superoxide production similar to that of STAR at concentrations ranging from 10-100 nmol/l, and propranolol (200 mumol/l) effectively inhibited it. K252a derivative NA332 did not show any potentiative effect on the production. PMA-induced superoxide production was inhibited by all compounds dose-dependently.(ABSTRACT TRUNCATED AT 250 WORDS)     

Knowledge, data, and models

The object-oriented approach to integrating knowledge data, and models is examined. Under the object-oriented paradigm, everything is an object, which is itself an encapsulation of data and methods to manipulate and access the data within the object. Thus knowledge, data, and models can be defined as special kinds of objects. Active knowledge/data language (KDL), a functional object-oriented database system is considered, covering the active-KDL-type system and functions, and query-driven simulation     

Comparing the motivations of Spanish and Finnish computer personnel with those of the United States

A survey of perceptions of IS personnel – managers, technical specialists and programmer/analysts – was conducted by the Association for Technical Information in Spain, using the JDS/DP, a modification of the job diagnostic survey instrument. Data were collected on fifteen job variables, related to four motivation aspects: job components, satisfaction levels, need for growth/achievement and goal participation/feedback. The results were compared with those of a similar survey for the same job types in Finland. Results were also compared with the norms developed for computer personnel in the USA. The survey revealed that personnel attracted to the computer field have a high need for growth and a low need for social interaction. It also revealed that the work itself was ranked highest among eleven motivating factors. For both Spain and Finland, the technical specialist job had a mis-match between the job's motivating potential and the employee's need for growth, compared with similar personnel in the USA. By examining the core job dimensions, managers can redesign the job to produce a match between these two major components of motivation.