Search results for: Kustaa Piha

Authors: Xiaoshu Lu, Päivi Leino-Arjas, Kustaa Piha, Akseli Aittomäki, Peppiina Saastamoinen, Ossi Rahkonen, Eero Lahelma

Abstract:

Sickness absence represents a major economic and social issue. Analysis of sick leave data is a recurrent challenge to analysts because of the complexity of the data structure which is often time dependent, highly skewed and clumped at zero. Ignoring these features to make statistical inference is likely to be inefficient and misguided. Traditional approaches do not address these problems. In this study, we discuss model methodologies in terms of statistical techniques for addressing the difficulties with sick leave data. We also introduce and demonstrate a new method by performing a longitudinal assessment of long-term absenteeism using a large registration dataset as a working example available from the Helsinki Health Study for municipal employees from Finland during the period of 1990-1999. We present a comparative study on model selection and a critical analysis of the temporal trends, the occurrence and degree of long-term sickness absences among municipal employees. The strengths of this working example include the large sample size over a long follow-up period providing strong evidence in supporting of the new model. Our main goal is to propose a way to select an appropriate model and to introduce a new methodology for analysing sickness absence data as well as to demonstrate model applicability to complicated longitudinal data.

Keywords: Sickness absence, longitudinal data, methodologies, mix-distribution model.

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Authors: T. Saarelainen, O. Piha, J. Orkas, P. E. Makkonen

Abstract:

The aim of this paper is to present current and future procedures in castings procurement. Differences in procurement are highlighted. The supplier selection criteria used in practice is compared to literature findings. Different trends related to supply chains are presented and it is described how they are reflected in reality to castings procurement. To fulfil the aim, interviews were conducted in nine companies using castings. It was found that largest casting users have the most subcontractor foundries and it is more typical that they have multiple suppliers for the same parts. Currently only two companies out of nine purchase castings outside Europe, but the others are also progressing in the same direction. The main reason is the need to lower purchasing costs. Another trend is that all companies want to buy cast components or sub-assemblies instead of raw castings from foundries. It was found that price is a main supplier selection criterion. All companies use competitive bidding in supplier selection.

Keywords: Casting, interview study, procurement, supplytrends.

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Authors: T. Saarelainen, O. Piha, P. Makkonen, J. Orkas

Abstract:

Global competition is tightening and companies have to think how to remain competitive. The main aim of this paper is to discuss how Finnish foundries will remain competitive. To fulfil the aim, we conducted interviews in nine companies using castings and analysed buyer–supplier relationships, current competitive advantages of Finnish foundries and customer perspectives on how Finnish foundries remain competitive. We found that the customerfoundry relationship is still closer to traditional subcontracting than partnering and general image of foundries is negative. Current competitive advantages of Finnish foundries include designing cooperation, proximity and flexibility. Casting users state that Finnish foundries should sell their know-how and services instead of their capacity, concentrate on prototype, single and short series castings and supply ready-to-install cast components directly to customers- assembly lines.

Keywords: Buyer-supplier relationship, casting, competitiveadvantage, customer prespective.

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