On hit-and-miss hyperspace topologies

summary:The Vietoris topology and Fell topologies on the closed subsets of a Hausdorff uniform space are prototypes for hit-and-miss hyperspace topologies, having as a subbase all closed sets that hit a variable open set, plus all closed sets that miss (= fail to intersect) a variable closed set belonging to a prescribed family $\Delta$ of closed sets. In the case of the Fell topology, where $\Delta$ consists of the compact sets, a closed set $A$ misses a member $B$ of $\Delta$ if and only if $A$ is far from $B$ in a uniform sense. With the Fell topology as a point of departure, one can consider proximal hit-and-miss hyperspace topologies, where ``miss'' is replaced by ``far from'' in the above formulation. Interest in these objects has been driven by their applicability to convex analysis, where the Mosco topology, the slice topology, and the linear topology have received close scrutiny in recent years. In this article we look closely at the relationship between hit-and-miss and proximal hit-and-miss topologies determined by a class $\Delta$. In the setting of metric spaces, necessary and sufficient conditions on $\Delta$ are given for one to contain the other. Particular attention is given to these topologies when $\Delta$ consists of the family of closed balls in a metric space, and their interplay with the Wijsman topology is considered in some detail

The Advisory System for Fertilizer Application in the German Democratic Republic Emphasizing the Minimization of Nitrogen Pollution

This paper describes one of three operational state computer systems used to give advice on agricultural problems in the GDR. The system, employed nationwide, is oriented to providing advice about fertilizer application on farms or even single fields. Of the other two computer systems, one is described in IIASA CP-79-18, "Environmental Problems of Agriculture II: Pest and Weed Management: Monitoring and Forecasting in the German Democratic Republic." The remaining operational system is applied to irrigation. At IIASA's request, the present paper emphasizes the methods of the system for determining the optimal amount of fertilizer to apply which allows for maximum agricultural production without wasting resources or harming the environment. The paper thus offers another contribution to the solution of nonpoint source chemical pollution problems which have been intensively studied at IIASA both in-house and in cooperation with other institutions

Carers of forensic mental health in-patients: what factors influence their satisfaction with services?

Background Families are the main caring resource for service users with severe mental health problems. There has been limited work examining the needs of carers of people using forensic mental health services. Aims This study aimed to gain an understanding of carers satisfaction with services in forensic mental health inpatient settings. Method A survey design was used with 63 carers interviewed by telephone using a structured interview schedule. The data was analysed both qualitatively and quantitatively. Results Most carers were pleased with the service provided although some negative views were expressed with specific types of contact. Giving appropriate information to carers was strongly associated with satisfaction with the service being provided. Conclusions Carer satisfaction with forensic mental health services is likely to be higher with services that address carers’ information needs. New ways of providing this information may offer greater opportunities for working with carers

Rapid tooling application for the evaluation of a greensand casting defect

Abstract: The ability to produce production quality tooling, directly from CAD data, through additive manufacturing (AM) processes has obvious advantages with regards to the reduced lead time and labour costs. This, together with the ability to simulate the metal casting process, opens new doors for researchers in the field of metal casting. This paper reviews the suitability of tooling produced in PA 2200 polyamide material, for use in a research environment, where the failure of greensand, a mixture of silica sand, bentonite (clay) and water, is to be replicated as it would occur in an industrial setting

Advances in Three Dimensional Printing - state of the art and future perspectives

Published ArticleThis paper surveys the current state and capabilities of Three Dimensional Printing (3DP). Based on its technical background - the ink jet printing as known from the printer and plotter industry - a classification structure has been developed and proposed. Different printing techniques and process concepts, together with their advantages and limitations are described and analysed. A large variety of manufacturing applications such as rapid pattern making and rapid tooling using the 3DP process directly or as core technology, as well as further implications in design and engineering analysis, medicine, and architecture are presented and evaluated. Some research issues are also discussed. An attempt, based on the state of the art, to show weaknesses and opportunities, and to draw conclusions about the future of this important process wraps up this paper

Classical and Bayesian estimation of stress-strength reliability of a component having multiple states

PurposeThis article presents the multi-state stress-strength reliability computation of a component having three states namely, working, deteriorating and failed state.Design/methodology/approachThe probabilistic approach is used to obtain the reliability expression by considering the difference between the values of stress and strength of a component, say, for example, the stress (load) and strength of a power generating unit is in terms of megawatt. The range of values taken by the difference variable determines the various states of the component. The method of maximum likelihood and Bayesian estimation is used to obtain the estimators of the parameters and system reliability.FindingsThe maximum likelihood and Bayesian estimates of the reliability approach the actual reliability for increasing sample size.Originality/valueObtained a new expression for the multi-state stress-strength reliability of a component and the findings are positively supported by presenting the general trend of estimated values of reliability approaching the actual value of reliability.</jats:sec

Long-term evaluation of patients with free tissue transfer to the lower leg in terms of functional, socioeconomic, and esthetic aspects

A retrospective, quantitative, long-term evaluation of patients with a free flap transfer to the lower extremity was carried out with respect to functional, socioeconomic, and esthetic outcome. The study included 57 patients who were examined by questionnaire filled out by both an examiner and the patients themselves. Indications for the free flaps were acute trauma or osteomyelitis and unstable scars arising from a previous trauma to the lower leg. The flap success rate was 94.7%. The period between the operation and evaluation was at least 3years. A local, flap-specific functional impairment was found in 17 patients (30%) and a general impairment of the lower extremity in 56% of the subjects. With respect to the socioeconomic outcome more than two-thirds of the patients returned to their previous occupation with no restrictions; approximately 20% of subjects had to switch to a less strenuous job. Although from the viewpoint of the examiner the esthetic appearance was satisfactory in 44 free flaps (77%), the majority of the patients were conscious of pigmental, textural, or contour changes which produced a subjective esthetic compromise in 56% of cases. In conclusion, despite a considerably high rate of local functional impairment the majority of patients (89%) were satisfied and judged the application of a free flap as having been beneficial in preventing a loss in socioeconomic status. The high rate of esthetic problems demonstrates the importance of including esthetic considerations in designing the free flap, in particular with regard to (a) meticulously tailoring the flap, (b) aiming at a homogeneous skin surface, and (c) thoroughly shaping the affected lower extremit

Prevention of Acute Hematoma After Face-Lifts

Acute hematoma remains one of the most frequently encountered complications after face-lift surgery. Several risk factors inherent to the patient and omission of certain intraoperative regimens are considered to cause hematoma. Significant risk factors include high blood pressure and male gender. Possible intraoperative regimens for the prevention of hematoma include tumescence infiltration without adrenaline, clotting of raw surfaces with fibrin glue, usage of drains, and application of compression bandages. However, little attention has been paid to postoperative measures. To examine whether different regimens in the postoperative phase can influence the incidence of hematoma, all face-lift patients who underwent surgery by a single surgeon in two different clinics (n=376) with two different postoperative regimens were evaluated over the course of 3years. In group 1 (n=308), all postoperative medication was administered on request including medication for pain control, blood pressure stabilization, and prevention of nausea and vomiting as well as postoperative restlessness and agitation. In group 2 (n=68), this medication was administered prophylactically at the end of the operation before extubation. The hematoma rate was 7% in group 1 and 0% in group 2. This study showed that the prophylactic use of medications (e.g., analgesics, antihypertonics, antiemetics, and sedatives) during the postoperative phase is superior to making drugs available to patients on request and can decrease the occurrence of acute hematoma in face-lift patient

Time and cost assessment of the manufacturing of tooling by metal casting in rapid prototyping sand moulds

Published ArticleIn this paper the time and cost parameters of tooling manufacturing by metal casting in rapid prototyping sand moulds are assessed and comparison is made with alternative tool making processes such as computer numerical control machining and investment casting (Paris Process). To that end two case studies obtained from local companies were carried out. The tool manufacturing was conducted according to a five steps process chain referred to as Rapid Casting for Tooling (RCT). These steps include CAD modelling, casting simulation, rapid prototyping, metal casting and finishing operations. In particular the Rapid Prototyping (RP) step for producing the sand moulds was achieved with the aid of an EOSINT S 550 Laser Sintering machine and a Spectrum 510 Three Dimensional Printer. The results indicate that RP is the rate determining step and cost driver of the proposed tooling manufacturing technique. In addition it was found that this tool making process is faster but more expensive than machining and investment casting