Combination free replacement and pro-rata warranty policy optimization model

Rizik koji prati razvoj proizvoda raste iz dana u dan. Jedan od faktora koji utiču na ovaj rizik je garancija proizvoda. Garancija je moćno marketinško oružje za proizvođača i istovremeno dobra zaštita za proizvođača i kupca, ali uvek podrazumeva dodatne troškove za proizvođača. Ovi troškovi zavise od karakteristika pouzdanosti proizvoda i parametara garancije. Ovaj rad se bavi optimizacijom ovih parametara za poznatu raspodelu otkaza proizvoda u cilju smanjivanja troškova garancije i istovremenog zadržavanja njene promotivne funkcije. Kombinacija garancije besplatne zamene i parcijalne garancije je izabrana kao model, pri čemu su varirane dužine perioda besplatne zamene i perioda parcijalne garancije, kao i koeficijenti koji definišu funkciju parcijalnih troškova. Vrednosti troškova garancije dobijene su pomoću analitičkih jednačina i simulacije. Dobijeni rezultati su prikazani i razmotreni i izneta su zaključna opažanja.Product development risk increases more and more every day. One of the factors that affect this risk is product warranty. Warranty is a powerful marketing instrument for the manufacturer and a good protection for both the manufacturer and the customer, but it always involves additional costs to the manufacturer. These costs depend on the product reliability and the warranty parameters. This paper deals with the optimization of these parameters for known product failure distribution to reduce the warranty costs to the manufacturer while retaining the promotional function of the warranty. Combination free replacement and pro-rata warranty policy is chosen as a model and the length of free replacement and pro-rata policy periods are varied, as well as the coefficients that define the pro-rata cost function. Warranty costs are obtained by using analytical equations and by simulation. The obtained results are shown and discussed and some concluding remarks are given

Strength verification of semi-trailer's self-supporting ADR tank body

Problematika rada odnosi se na distribuciju opterećenja kroz zonu oslanjanja rezervoara. U radu se potencira značaj uticaja koji konstrukcija oslonih jastuka rezervoara, odnosno interakcija sa donjim postrojem cisterne ima na njegovo ponašanje i pouzdanost. U radu je razmatrano aktuelno stanje, uz komentar zahteva i kriterijuma koji normativno regulišu ovaj segment. Osnovni cilj rada je da ukaže na nedoslednost i nepreciznost aktuelne regulative i ponudi način za prevazilaženje uočenih problema primeren stanju tehnike u segmentu identifikacije ponašanja i verifikacije konstrukcija sa stanovišta čvrstoće. U ovom smislu predstavljena je konkretna primena razvijenog metodološkog prilaza na primeru specifičnog rešenja oslanjanja samonosećeg ADR rezervoara poluprikolice cisterne u zoni vučnog čepa, uz ilustrativno predstavljanje proračunskih odziva karakterističnih varijanti i režima opterećenja, uključujući sva potrebna pojašnjenja i komentare dobijenih rezultata.This paper analyzes load distribution throughout the tank body suspension zone. It points out the importance of influence that the design of the link between the tank wall and the base of the tank vehicle (suspension cushion zone) has on the structure behaviour and reliability. In this study, the current state is considered, giving comments on the requirements and the criteria which make a normative regulation of this segment. The basic purpose of this study is to point out the inconsistency and inaccuracy of current regulations as well as to offer a technically adequate way of resolving the stated problems in the segment of identification of behaviour and verification of construction from the strength point of view. In addition, we have illustrated how a developed methodological approach has been applied to a particular model of self-supporting ADR tank body of semi-trailers in the fifth wheel coupling pin zone, including the characteristic graphic presentation of carried out calculations and necessary explanation and comments

Strength verification of semi-trailer's self-supporting ADR tank body

Problematika rada odnosi se na distribuciju opterećenja kroz zonu oslanjanja rezervoara. U radu se potencira značaj uticaja koji konstrukcija oslonih jastuka rezervoara, odnosno interakcija sa donjim postrojem cisterne ima na njegovo ponašanje i pouzdanost. U radu je razmatrano aktuelno stanje, uz komentar zahteva i kriterijuma koji normativno regulišu ovaj segment. Osnovni cilj rada je da ukaže na nedoslednost i nepreciznost aktuelne regulative i ponudi način za prevazilaženje uočenih problema primeren stanju tehnike u segmentu identifikacije ponašanja i verifikacije konstrukcija sa stanovišta čvrstoće. U ovom smislu predstavljena je konkretna primena razvijenog metodološkog prilaza na primeru specifičnog rešenja oslanjanja samonosećeg ADR rezervoara poluprikolice cisterne u zoni vučnog čepa, uz ilustrativno predstavljanje proračunskih odziva karakterističnih varijanti i režima opterećenja, uključujući sva potrebna pojašnjenja i komentare dobijenih rezultata.This paper analyzes load distribution throughout the tank body suspension zone. It points out the importance of influence that the design of the link between the tank wall and the base of the tank vehicle (suspension cushion zone) has on the structure behaviour and reliability. In this study, the current state is considered, giving comments on the requirements and the criteria which make a normative regulation of this segment. The basic purpose of this study is to point out the inconsistency and inaccuracy of current regulations as well as to offer a technically adequate way of resolving the stated problems in the segment of identification of behaviour and verification of construction from the strength point of view. In addition, we have illustrated how a developed methodological approach has been applied to a particular model of self-supporting ADR tank body of semi-trailers in the fifth wheel coupling pin zone, including the characteristic graphic presentation of carried out calculations and necessary explanation and comments

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries