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At least 469 records · Page 26Linked to original sources
PubMed2001

Towards on-line quantification of flocs and filaments by means of image analysis for optimization and control of activated sludge plants.

One of the main reasons for failing of the sedimentation process in activated sludge waste water treatment systems is filamentous bulking. This is a problem of world-wide nature that occurs when the ratio of filamentous to floc forming bacteria is too large. A fully automatic image analysis method for recognizing flocs and filaments in an activated sludge sample is presented. Computer generated images of flocs and filaments, as well as images of activated sludge, are used to assess the capability of simple shape descriptors to distinguish between flocs and filaments. Five different shape descriptors are scrutinized, three of which are derived from size descriptors, namely, the aspect ratio, the roundness, and the form factor. The fractal dimension and the reduced radius of gyration complete the list. The results yield that the form factor is the least suitable and the reduced radius of gyration is the most suitable shape descriptor to accurately identify flocs and filaments in a random activated sludge sample. Based on this, the ratio of flocs to filaments can be estimated automatically. Furthermore, it is proposed that by combining this information with a total biomass concentration measurement, the individual concentrations of flocs and filaments can be determined. Consequently, the method presented may form the basis for a sensor that acts as an early warning system for filamentous bulking.

Beer↗
PubMed2005

[Record optimization and control of medical property stocks].

To conduct the adequate control of medical property coming to the medical provision institution the software was developed where the special attention was paid to the functions of control-and-operational department. It is conditioned by the fact that together with cost control it is necessary to record the medical property in natural values. The use of the created program in local net system allowed organizing the operative control of material stocks at all stages of its movement.

Military Medicine↗
PubMedDate not supplied

How to maintain optimal glycaemic control in diabetes.

Despite national and local guidelines for glycaemic control, current management of glycaemia can fall significantly short of accepted goals. This article discusses the recommended glycaemic control goals and barriers that can prevent their achievement. It examines key recommendations to enable health care providers to overcome these barriers.

Blood Glucose↗
PubMed1991

[The use of computers and mathematical methods for optimizing epidemic control measures with respect to measles infection].

The potentialities of computers for the study of the effectiveness of immunization have been demonstrated and the mathematical model for the prediction of the proportion of children, seronegative to measles, derived on the basis of the data on the average measles morbidity in different groups for a given period. A multifactor analysis of a large scope of data obtained in seroepidemiological survey and a retrospective analysis of measles morbidity on the basis of data collected in two districts of Moscow have been carried out with the use of computers and mathematical methods.

Age Factors↗
PubMed1986

Optimizing glycemic control: can insulin dependent diabetic patients rely on their perception of blood glucose fluctuations in order to make therapeutic decisions?

30 insulin dependent diabetic (IDD) patients without clinically evident autonomic neuropathy were asked on 128 occasions to estimate quantitatively what they believed their capillary blood glucose (CBG) to be (predicted blood glucose--PBG) immediately before an actual CBG measurement was performed (real blood glucose--RBG). A statistically significant correlation was found between the pooled RBG's and PBG's of our patient population (r = 0.57, p less than 0.001). However, there was a notable skewing of the RBG/PBG curve, evidencing a tendency of our patients' predictions to be closer to normality. This is further documented by the fact that the mean M value of the RBG's of each of the 11 patients with more than 6 predictions was significantly greater than the mean M value of the corresponding PBG's. Within the ranges of hypoglycemia (RBG less than or equal to 3.3 mmol/l) and of normoglycemia (3.4-7.8 mmol/l) there was no correlation between RBG's and PBG's. With RBG's greater than or equal to 7.8 mmol/l the correlation was statistically significant (r = 0.41, p less than 0.01). When the pooled predictions were analyzed according to qualitative accuracy for different ranges of RBG the following trend emerges: for RBG's less than or equal to 3.3 mmol/l (60 mg%), 2/11 predictions were accurate (18%), for RBG's greater than or equal to 12.3 mmol/l (221 mg%), 30/37 (81%) and for RBG's between 3.4 and 12.2 mmol/l (61-220 mg%), 44/80 (55%). In conclusion, our patients as a whole showed an ability to discriminate between high, normal and low levels of blood glucose, albeit with a strong bias to predict values closer to the normal range.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Optimizing local control in soft tissue sarcoma of the extremity.

Extremity soft tissue sarcoma is a rare malignancy in which a high rate of local control can be achieved with multimodal regimens and without excessive treatment-related morbidity. This article reviews the current status of evaluation, staging, and local treatment of these tumors. Evidence shows that surgical approaches that maximize local control have little effect on the development of distant metastasis and overall survival. The goal of local treatment, therefore, is a balance of adequate local control with limb salvage and minimal therapeutic morbidity. A variety of limb-sparing approaches using various adjuvant modalities in addition to conservative resection are discussed, including reported local control and complication rates. Treatment paradigms are then presented for the management of extremity soft tissue sarcoma of varying stages. Further studies are needed to define precisely the role, type, and timing of chemotherapy and radiotherapy in addition to surgery in the management of this disease with respect to local control and distant metastasis.

Brachytherapy↗
PubMed2001

On the optimization of drug release from multi-laminated polymer matrix devices.

This work presents a systematic optimization framework to achieve desired release rates in drug delivery devices using multi-laminated layers. A simple mathematical model is used to describe the transient mass transfer between successive layers, laminated together to form matrices with different initial concentrations, drug diffusivities and thickness. First, an efficient analytical-based optimization approach is investigated to define the optimal nonuniform initial drug distribution for constant diffusivity profile. The results obtained are in a good agreement with relevant work from the literature resorting to advanced optimal control techniques. Then, a formal dynamic optimization approach is employed, to systematically explore the synergistic benefits when all the available controllable parameters are simultaneously optimized, in order to achieve a drug release profile as close to a desired profile as possible for the entire period of operation. The optimization results lead to significantly improved constant release profiles.

Drug Delivery Systems↗
PubMed1991

Optimal coordination and control of posture and locomotion.

This paper presents a theoretical model of stability and coordination of posture and locomotion, together with algorithms for continuous-time quadratic optimization of motion control. Explicit solutions to the Hamilton-Jacobi equation for optimal control of rigid-body motion are obtained by solving an algebraic matrix equation. The stability is investigated with Lyapunov function theory, and it is shown that global asymptotic stability holds. It is also shown how optimal control and adaptive control may act in concert in the case of unknown or uncertain system parameters. The solution describes motion strategies of minimum effort and variance. The proposed optimal control is formulated to be suitable as a posture and stance model for experimental validation and verification. The combination of adaptive and optimal control makes this algorithm a candidate for coordination and control of functional neuromuscular stimulation as well as of prostheses.

Algorithms↗