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The purpose of this paper is to solve difficult estimation problem on aircraft sudden fault by proposing a new pre-estimating method according to the energy evolution degree of the sensitive parameters to estimate the sudden fault. The sudden fault affects seriously the flight safety of aircraft.

It is based on the dissipative structure theory, and the evolution process of energy parameters is utilized. First, the evolution key points of sudden fault are determined by the time-varying entropy of sensitive parameters and the frequency band energy distribution. Then, we can obtain the evolution degree of sample while the evolution key points import the logistic regression (LR) model, and one can establish the pre-estimation model by means of relevance vector machine (RVM). While the evolution feature vector imports the RVM pre-estimation model, one can pre-estimate the sudden fault of aircraft.

The simulation results showed that this method can not only track the evolution process of aircraft sudden fault but also estimate its evolution degree, and it has a higher pre-estimating accuracy.

It provides a new way to forecast the sudden fault and increase the security of aircraft.

This paper proposes a pre-estimating method on aircraft sudden fault. It is based on the dissipative structure theory and the energy-sensitive parameters of the sudden faults are used. This method can enhance the security of aircraft and increase the protective ability of sudden fault on aircraft.

The purpose of the present study is to examine how perceived employability relates to job exhaustion, psychological symptoms and self‐rated job performance in involuntary and voluntary temporary employees compared to permanent employees.

The study is based on a cross‐sectional design using a sample of university teachers and researchers (n=1,014) from two Finnish universities. Of the sample, 40 percent (n=408) are permanent employees, 49 percent (n=495) involuntary and 11 percent (n=111) voluntary temporary employees. Most respondents (54 percent) have education above a Master's degree, the average age is 43 years, and 58 percent are women.

The results of general linear model analyses show that perceived employability promotes favorable outcomes among all respondents. However, the negative relationship between perceived employability and job exhaustion and psychological symptoms is stronger among voluntary than among involuntary temporary employees.

The study indicates that although perceived employability seems to be important to all employees, involuntary temporary employees benefit least from high perceived employability in terms of individual well‐being.

The purpose of this paper is to investigate the feasibility of using land grid array (LGA) solder joints as a second-level interconnection option in low-temperature co-fired ceramic (LTCC)/printed wiring board (PWB) assemblies for telecommunication applications. The characteristic behaviour of two commercial lead-free solder materials (Sn4Ag0.5Cu and Sn3Ag0.5Cu0.5In0.05Ni) in reflow processes and thermal cycling tests are also evaluated.

The effect of the reflow temperature profile on voiding in two lead-free solders in LTCC/PWB assemblies was investigated using X-ray and scanning electron microscopy (SEM) investigations. The test assemblies were fabricated and exposed to a temperature cycling test (TCT) in a 0-100°C or −40 to 125°C temperature range. Organic PWB material with a low coefficient of thermal expansion (CTE) was primarily used. In addition, to compare LGA assemblies with low and high global thermal mismatches, an LTCC module/FR-4 assembly was also fabricated and exposed to a TCT in a 0-100°C temperature range. The characteristic lifetime of the test assemblies was determined using DC resistance measurements. The failure mechanisms of the interconnections were verified using scanning acoustic microscopy, SEM and finite element (FE)-SEM investigations.

This work showed that the solderability of AgPt-metallized LTCC modules was poor, resulting in excessive voiding. This problem was avoided by using pre-tinned modules. In the test assemblies, the Sn4Ag0.5Cu joints had a lower void content and a higher characteristic lifetime compared with the Sn3Ag0.5Cu0.5In0.05Ni joints. Furthermore, it was observed that the Sn3Ag0.5Cu0.5In0.05Ni joints were more prone to fail along the interface between the Ag₃Sn layer and the solder matrix than were the Sn4Ag0.5Cu joints. It was assumed that the observed difference in the primary failure mechanisms resulted in the decreased lifetime duration of the SnAgCu-InNi/Arlon in both temperature cycling conditions.

The results proved that the solderability of both solders in AgPt-metallized modules in a typical surface mount technology process was poor; however, the solderability of the test modules can be notably enhanced with pre-tinned pads. This work also demonstrated the effect of the metallization/solder pair on the failure mechanisms and failure rate in LTCC/PWB assemblies with LGA joints; the work also proved in the TCT, over a temperature range of 0-100°C, that using the present LGA joints in LTCC/PWB assemblies with a high global thermal mismatch did not increase the lifetime duration of the joints to the preferred level (3,000 cycles), whereas the performance of these joints was adequate in assemblies with a low global thermal mismatch. Moreover, the results indicated that using the LGA joint configuration enhanced the reliability of the LTCC/PWB assemblies compared with similar assemblies with collapsible ball grid array solder spheres.

The purpose of this research is to explore how employee attitudes affect management behaviour in the corporate entrepreneurship (CE) setting. The paper focuses on the co‐evolutionary processes of practices and elements of the social structure, i.e. simultaneous top‐down and bottom‐up influences.

Organisation‐level data from individuals in the Finnish public‐sector health and social care organisation was obtained. The questionnaire comprised Likert‐scale attitude statements on different aspects of management behaviour, enabling structures, and individual attitudes. The data analysed consisted of 523 responses. Factor analysis and reliability tests were used to create aggregated measures for different CE antecedents and hierarchical regression analysis in order to test the causal model derived from the previous literature.

Empirical evidence of the crucial role of individual attitudes and action in CE was found, thus indicating that certain attitude types influence management behaviour. Straightforward communication emerged as the most important bottom‐up modality in that it is needed if individual attitudes are to influence managers.

The results challenge and complement previous research in the field of CE in recognising the crucial role of individual employees. The findings suggest that CE is not catalysed from the bottom up by silent followers, even though superiors find them comfortable to manage. It is rather the self‐confident and satisfied corporate entrepreneurs with initiative who critically question the existing working modes and thus catalyse CE. Finally, suggestions for further research were offered.

The purpose of this paper is to describe the behavior of different lead-free solders (95.5Sn3.8Ag0.7Cu, i.e. SAC387 and Sn7In4.1Ag0.5Cu, i.e. SAC-In) in thermomechanically loaded non-collapsible ball grid array (BGA) joints of a low-temperature co-fired ceramic (LTCC) module. The validity of a modified Engelmaier’s model was tested to verify its capability to predict the characteristic lifetime of an LTCC module assembly implementable in field applications.

Five printed wiring board (PWB) assemblies, each carrying eight LTCC modules, were fabricated and exposed to a temperature cycling test over a −40 to 125°C temperature range to determine the characteristic lifetimes of interconnections in the LTCC module/PWB assemblies. The failure mechanisms of the test assemblies were verified using scanning acoustic microscopy, scanning electron microscopy (SEM) and field emission SEM investigation. A stress-dependent Engelmaier’s model, adjusted for plastic-core solder ball (PCSB) BGA structures, was used to predict the characteristic lifetimes of the assemblies.

Depending on the joint configuration, characteristic lifetimes of up to 1,920 cycles were achieved in the thermal cycling testing. The results showed that intergranular (creep) failures occurred primarily only in the joints containing Sn7In4.1Ag0.5Cu solder. Other primary failure mechanisms (mixed transgranular/intergranular, separation of the intermetallic compound/solder interface and cracking in the interface between the ceramic and metallization) were observed in the other joint configurations. The modified Engelmaier’s model was found to predict the lifetime of interconnections with good accuracy. The results confirmed the superiority of SAC-In solder over SAC in terms of reliability, and also proved that an air cavity structure of the module, which enhances its radio frequency (RF) performance, did not degrade the reliability of the second-level interconnections of the test assemblies.

This paper shows the superiority of SAC-In solder over SAC387 solder in terms of reliability and verifies the applicability of the modified Engelmaier’s model as an accurate lifetime prediction method for PCSB BGA structures for the presented LTCC packages for RF/microwave telecommunication applications.

The authors aim to compare how formal flexibility, such as telework, differs from informal overtime work at home regarding the work-family interface.

By using data from the Finnish Quality of Work Life Surveys from 2003 and 2008, the positive and negative measures concerning the work-family interface are examined through logistic regression analysis.

Employees doing informal overtime at home are more likely to be affected by negative emotions concerning work disrupting family lives. Additionally, negotiations between couples over the allocation of time become areas of conflict. Only weak evidence is provided for both telework and informal work at home supporting family life.

In studying homeworking, it is important to separate between formal and informal flexibility at work. The data exceptionally enable that. The limitations of the data are cross-sectionality and only a few measures for assessing the positive work-family interface.

The contribution of the study is to show how informal overtime at home is related with stronger negative implications for work-family interface, when separated from telework. The article discusses how well-intentioned working schedule flexibility results in family life being infringed upon. Informal work may help attain a better work-family interface, but, with dual-earner employment being predominant in Finland, informal overtime work can increase pressures on families. The authors encourage the policy- and organisation-level recognition of informal overtime risks.

The purpose of this paper is to determine the nature of the academic skills deficits in male offenders and their relation to neurocognitive deficits.

In total, 72 Finnish male prisoners were tested with regard to reading, spelling, and mathematical abilities.

Low academic skills, especially reading, were related to poor neurocognitive performance in verbal memory, visual memory, attention, and motor dexterity. The results showed a high number (29-36 percent) of reading and spelling disorders. In all, 15 percent of those with medium to severe problems in academic skills had marked difficulties in mathematics. In total, 88 percent of the participants with at least one problem area in literacy skills had neurocognitive deficits. In the present study, the pervasive neurocognitive deficits, occurring comorbidly with reading and spelling difficulties, seem to refer to a fundamental set of deficits which are only minimally explained by IQ, educational background or training.

Reading and spelling difficulties could be seen as functional illiteracy which, combined with a broad spectrum of neuropsychological function deficits, pose a challenging task for rehabilitation. Only after proper identification of deficits has been achieved is it possible to set goals and select the appropriate means for rehabilitation. One obvious limitation is the moderate number of subjects (n=72).

It may not be enough just to train reading or develop literacy activities among prisoners; focussing intervention on comprehensive neurocognitive deficits is also necessary.

Correlates and comorbidity between academic difficulties and neurocognitive deficits among offenders, especially in arithmetic difficulties, have been less studied.

A case study at Senate Properties, a Finnish building owner organisation, for theory building was conducted to provide significant insights into strategic planning in partnership networks with a view to developing interaction in a triadic alliance. The purpose of this paper is to describe how a Finnish building owner organisation, Senate Properties, the focal firm of the studied network, manages multi‐level interaction in the alliance network of the case study.

In this paper, the building owner's role is studied by using two network analysis studies. The emergent phase of a “triadic alliance” of service providers, building owners as contract managers, and the end‐users of services is analysed by using two separate qualitative network analysis studies.

The case study indicates that the networks of building users, owners, facilities management parties and service providers can improve their interaction and cooperation by multilevel interaction building, mutual orientation building in groups and formation of boundary‐spanning roles. We therefore present a model or a framework for interaction building in triadic networks that is derived from a knowledge base that can better explain the requirements of core businesses, key real estate and facilities services attributes and options evaluation to meet dynamic changes.

The paper suggests that organisations involved in facilities management that enter into an alliance have to communicate and proactively exchange information to strengthen the interaction and cooperation between network members. For success, each network member should share information and each must learn from the others.

The interaction approach of network analysis takes place in a new building owner centred environment. The paper argues on a general level that to understand the complicated roles within the workplace environment, it is necessary to study the interaction needs of different functions.

The purpose of this paper is to examine the level and predictors of work engagement among service sector employees in eight European countries.

The work seeks to discover if job demands and resources, i.e. job autonomy and social support, affect work engagement in differing ways in different countries when socio‐demographical variables and work‐related factors are controlled. The study is based on a statistical analysis of survey data from Bulgaria, Finland, Germany, Hungary, The Netherlands, Portugal, Sweden and the UK in 2007 (n=7,867). The data represent four economic sectors: retail trade, finance and banking, telecoms and public hospitals.

The results show that the level of work engagement varies not only between countries but also between those four economic sectors within each country. Additionally, the findings indicate that demands decrease work engagement, while autonomy and support increase it. Although the effects are mainly the same across the countries, the article also points out some exceptions in this regard.

Although the paper is built upon established theories about job demands and autonomy, it uses a newer work engagement approach, produces cross‐national knowledge about work engagement and its predictors. Cross‐national approaches to work engagement are still rare.

Previous research has been relatively insensitive to the potential combined effects that the shared industry background and country of origin might play in the development of MNCs. This is although there are various external constituents that pose distinctive demands especially on such groups of MNCs. The 15-year period of internationalization of three major Finnish paper companies examined in this study represents MNC development as a collective endeavor in which individual companies are especially influenced both by each other and by their joint external constituents. These influences materialize in analogous timing and patterns of internationalization across individual companies. In its entirety, the study thus suggests that the development of MNCs which operate in the same line of industry and originate from the same country can be considered an outcome of a mutual process that involves interaction both with each other and their shared external constituents. This also means that MNCs then are not only competitors, but simultaneously also a source of mutual support in their ever-continuing evolution.