G.P. Kothiyal, S.V. Phadnis, V.K. Shrikhande, T. Mirza, M.K. Totlani and V.C. Sahni
Investigates the chemical resistance properties of lead silicate glasses suitable for compression‐type glass‐to‐metal (GM) seals, to aggressive solvents, containing different…
Abstract
Investigates the chemical resistance properties of lead silicate glasses suitable for compression‐type glass‐to‐metal (GM) seals, to aggressive solvents, containing different amounts of Na, K, and Ba as modifier ions, in acidic and alkaline media. In general attack rate was observed to be higher in alkaline medium, with maximum dissolution of 53.35 mg/cm2 compared to the maximum of 10.6mg/cm2 in acidic medium after 50 hour exposure. An increase in the concentration of BaO was found to decrease the degradation rate, while samples with higher molar amounts of either Na2O or K2O showed more though similar damage rates. The degradation rate was observed to be linear for higher BaO concentration in alkali solution, whereas in other cases accelerated rates were observed with longer exposure time. GM seals prepared with glass, having higher BaO content, were less susceptible to damage and had higher insulation resistances.
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Shobha Manikandan, Jagannath, V.K. Shrikhande and G.P. Kothiyal
To study the degradation behaviour of borosilicate glass, which is suitable for hermetic sealing with Molybdenum and Kovar (Fe/Co/Ni) alloys, as a function of concentration and…
Abstract
Purpose
To study the degradation behaviour of borosilicate glass, which is suitable for hermetic sealing with Molybdenum and Kovar (Fe/Co/Ni) alloys, as a function of concentration and temperature in both acidic and alkaline media for long durations, up to 160 h.
Design/methodology/approach
The degradation (weight loss in mg/cm2 of the glass sample) was determined by immersing the glass sample in HCl and NaOH solutions at different temperatures for different periods extending up to 300 h. The damage to the glass surface was seen under an optical microscope and the chemical species on the corroded surface were identified by electron spectroscopy for chemical analysis.
Findings
The borosilicate glass, having the nominal composition 0.70 SiO2, 0.039 Na2O, 0.028 K2O, 0.21 B2O3, 0.01 Al2O3 was synthesized by melt and quench techniques. Degradation (corrosion) behaviour of this glass was investigated by immersing glass samples in 5 and 10 per cent HCl and 5 per cent NaOH solutions at different temperatures up to 90°C, for different periods and measuring dissolution rate (weight loss in mg/cm2 of the sample). Dissolution rates were found to be 5.47 mg/cm2 and 46.77 mg/cm2 in 5 per cent NaOH at 60 and 90°C, respectively, whereas they were comparatively low (2.59 and 5.80 mg/cm2 at 60 and 90°C, respectively, in 5 per cent HCl medium) after 160 h of total immersion period. The plot of dissolution rates against the temperatures showed the nonlinear behaviour at higher temperatures, probably due to the change in mechanism of corrosion. XPS studies exhibited the chemical species on the corroded surfaces. The optical microscopy of the corroded surface revealed that the corrosion mechanisms were different in acid and alkali media.
Research limitations/implications
The degradation behaviour of borosilicate glass having a specific composition has been investigated as a function of concentration and temperature in both acid and alkaline media. The mixed alkali effect on the degradation behaviour may be studied by varying relative amount of Na2O and K2O in the glass composition.
Practical implications
The glass composition under the present study has been used for fabrication of matched type glass‐to‐metal (GM) seals with kovar alloy. In this respect the present study is significant in deciding the environmental conditions for its use.
Originality/value
The degradation behaviour of borosilicate glass having alkali and alkaline earth metal oxides has been investigated as a function of concentration and temperature in both acid and alkali media. The findings in this paper have the potential implications in deciding the environmental conditions for use of GM seals fabricated using this glass.
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K. Gopikrishna and Manish Shrikhande
The purpose of this paper is to present a new hierarchical finite element formulation for approximation in time.
Abstract
Purpose
The purpose of this paper is to present a new hierarchical finite element formulation for approximation in time.
Design/methodology/approach
The present approach using wavelets as basis functions provides a global control over the solution error as the equation of motion is satisfied for the entire duration in the weighted integral sense. This approach reduces the semi‐discrete system of equations in time to be solved to a single algebraic problem, in contrast to step‐by‐step time integration methods, where a sequence of algebraic problems are to be solved to compute the solution.
Findings
The proposed formulation has been validated for both inertial and wave propagation types of problems. The stability and accuracy characteristics of the proposed formulation has been examined and is found to be energy conserving.
Originality/value
The paper presents a new hierarchical finite element formulation for the solution of structural dynamics problems. This formulation uses wavelets as the analyzing basis for the desired transient solution. It is found to be very well behaved in solution of wave‐propagation problems.
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Christine Helliar, Theresa Dunne and Lance Moir
The past twenty years have seen a significant increase in the use of derivative financial instruments by companies throughout the world (Berkman and Bradbury 1996; Berkman…
Abstract
The past twenty years have seen a significant increase in the use of derivative financial instruments by companies throughout the world (Berkman and Bradbury 1996; Berkman, Bradbury and Magan, 1997a; Berkman, Bradbury, Hancock and Innes, 1997b; Bodnar, Hayt, Marston and Smithson, 1995; Bodnar, Hayt and Marston, 1996; 1998; Collier and Davis, 1985). This paper examines the impact of Financial Reporting Standard 13: Derivatives and Other Financial Instruments, Implementation and Disclosures, on treasury department activities. In particular, the researchers conducted interviews with UK treasury department staff to assess their general attitudes to, and the perceived impact of, FRS 13. In general, the treasurers responded favourably to the standard, and considered the narrative disclosures to be particularly useful. The numerical disclosures were considered to be very detailed and specialised; interviewees thought that users might have difficulty in understanding them. However, the implementation of IAS 39, that becomes mandatory for all EC countries from 2005, was causing treasurers far more concern.
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Raimond Maurer and Shohreh Valiani
This study seeks to examine the effectiveness of controlling the currency risk for international diversified mixed‐asset portfolios via two different hedge instruments, currency…
Abstract
Purpose
This study seeks to examine the effectiveness of controlling the currency risk for international diversified mixed‐asset portfolios via two different hedge instruments, currency forwards and currency options. So far, currency forward has been the most common hedge tool, which will be compared here with currency options to control the foreign currency exposure risk. In this regard, several hedging strategies are evaluated and compared with one another.
Design/methodology/approach
Owing to the highly skewed return distributions of options, the application of the traditional mean‐variance framework for portfolio optimization is doubtful. To account for this problem, a mean lower partial moment model is employed. An in‐the‐sample as well as an out‐of‐the sample context is used. With in‐sample analyses, a block bootstrap test has been used to statistically test the existence of any significant performance improvement. Following that, to investigate the consistency of the results, the out‐of‐sample evaluation has been checked. In addition, currency trends are also taken into account to test the time‐trend dependence of currency movements and, therefore, the relative potential gains of risk‐controlling strategies.
Findings
Results show that European put‐in‐the‐money options have the potential to substitute the optimally forward‐hedged portfolios. Considering the composition of the portfolio in using in‐the‐money options and forwards shows that using any of these hedge tools brings a much more diversified selection of stock and bond markets than no hedging strategy. The optimal option weights imply that a put‐in‐the‐money option strategy is more active than at‐the‐money or out‐of‐the‐money put options, which implies the dependency of put strategies on the level of strike price. A very interesting point is that, just by dedicating a very small part of the investment in options, the same amount of currency risk exposure can be hedged as when one uses the optimal forward hedging. In the out‐of‐sample study, the optimally forward‐hedged strategy generally presents a much better performance than any types of put policies.
Practical implications
The research shows the risk and return implications of different currency hedging strategies. The finding could be of interest for asset managers of internationally diversified portfolios.
Originality/value
Considering the findings in the out‐of‐sample perspective, the optimally forward‐hedged minimum risk portfolio dominates all other strategies, while, in the depreciation of the local currency, this, together with the forward‐hedged tangency portfolio selection, would characterize the dominant portfolio strategies.
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Siti Zati Hanani Mahamood and Mohamad Syazli Fathi
This paper aims to improve the seismic building design (SBD) work process for Malaysian Government projects.
Abstract
Purpose
This paper aims to improve the seismic building design (SBD) work process for Malaysian Government projects.
Design/methodology/approach
Semi-structured interviews were virtually conducted to a small sample size of internal and external stakeholders from the Malaysian Government technical agency. There were seven of them, comprising Structural Engineers, an Architect, a Quantity Surveyor and consultants-linked government projects. The respondents have at least five years of experience in building design and construction.
Findings
The paper evaluates the current SBD work process in the government technical agency. There were four main elements that appear to need to be improved, specifically in the design stage: limitations in visualization, variation of works, data management and coordination.
Research limitations/implications
This study was limited to Malaysian Government building projects and covered a small sample size. Therefore, further research is recommended to extend to other government agencies or ministries to obtain better results. Furthermore, the findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.
Practical implications
The findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.
Social implications
This study was limited to government building projects and covered a small sample size. Therefore, further research is recommended to extend to other government agencies or ministries to obtain better results. Furthermore, the findings and proposal for improvements to the SBD work process can also be replicated for other similar disasters resilience projects.
Originality/value
This study provides an initial step to introduce the potential of building information modeling for SBD in implementing Malaysian Government projects. It will be beneficial both pre-and post-disaster and is a significant step toward a resilient infrastructure and community.
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Prabhat Kumar, Ashwini Kumar and Amita Sinvhal
For a state like Uttarakhand, which is located in the seismically active Himalayan region and in the vicinity of plate boundaries, estimation of seismic hazards and the…
Abstract
Purpose
For a state like Uttarakhand, which is located in the seismically active Himalayan region and in the vicinity of plate boundaries, estimation of seismic hazards and the preparation of a zoning map are an urgent necessity. This paper aims to focus on this hazard.
Design/methodology/approach
In total, 32 potential seismo‐tectonic source zones were identified in a very wide area in and around the state, on the basis of seismicity and tectonics, and the longer ones were segmented. The maximum magnitude that each seismo‐tectonic source zone can support was then estimated. The seismic hazard due to each seismo‐tectonic source zone was assessed at 180 sites, in terms of peak ground acceleration (PGA).
Findings
The maximum PGA at each site varied between 0.06g and 0.50g. The seismic hazard was highest around the main central thrust and the main boundary thrust, and five other thrusts between these two thrusts. This assessment was adapted to make a seismic zoning map of Uttarakhand, with five distinct zones.
Research limitations/implications
If seismo‐tectonic source zones from the contiguous regions of Nepal and Tibet were included as part of this assessment, then a higher hazard would be expected in Uttarakhand.
Practical implications
Threat perceptions of a potential earthquake disaster can be assessed in this zoning map. Disaster mitigation strategies will vary geographically, with priorities defined by the zoning map presented here. The methodology evolved has the potential to be extended to other vulnerable states in the Himalayan arc.
Originality/value
The seismic hazard assessed has been adapted to formulate a seismic zoning map of Uttarakhand.
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Mohammed Z. Salem, Samir Baidoun, Grace Walsh and Netham Sweidan
The purpose of this study is to examine the impact of female portrayal in advertisements on Palestinian female consumers’ purchasing decisions. TV and online media were selected…
Abstract
Purpose
The purpose of this study is to examine the impact of female portrayal in advertisements on Palestinian female consumers’ purchasing decisions. TV and online media were selected as the medium for the study. Specifically, the researchers examine the one-dimensional sexualized female portrayal in advertisements.
Design/methodology/approach
Culture is used as the lens through which the study examines the relationship between independent and dependent variables concerning the topic of this study. The study collected primary data from 395 Palestinian participants through a survey questionnaire.
Findings
The findings of the study revealed that there is a relationship between the independent variable (the sexualized female portrayal in foreign advertisements – advertisements originating in foreign countries) and the dependent variable (Palestinian female consumers’ purchase decision). Additionally, the study found that the cultural differences between Palestine and other foreign countries have a negative impact on the Palestinian female consumers’ perception of the product being advertised.
Practical implications
Although traditional marketing procedures would allow companies to filter and adapt particular adverts to suit various cultural, social and political environments, the advent of the open web and satellite TV channels extend the advertisements reach to audiences beyond their intended demographic.
Originality/value
This is the first study set in the Arab context (including Palestine) to explore the impact of sexualized female portrayal in advertisements on Palestinian female consumers’ purchasing decision.