Modern avionics can account for around 30% of the total cost of the aircraft. Therefore, it is es... more Modern avionics can account for around 30% of the total cost of the aircraft. Therefore, it is essential to reduce the operational cost of avionics during a lifetime. This article addresses the critical scientific problem of creating the appropriate maintenance models for digital avionics systems that significantly increase their operational effectiveness. In this research, we propose the lifecycle cost equations to select the best option for the maintenance of digital avionics. The proposed cost equations consider permanent failures, intermittent faults, and false-positives occurred during the flight. The lifecycle cost equations are determined for the warranty and the post-warranty interval of aircraft operation. We model several maintenance options for each period of service. The cost equations consider the characteristics of the permanent failures and intermittent faults, conditional probabilities of in-flight false-positive and true-positive as well as the cost of different mai...
Objective: To analyze the factors associated with adverse effects in elderly women receiving chem... more Objective: To analyze the factors associated with adverse effects in elderly women receiving chemotherapy for breast cancer. Study Design: Comparative Cross-sectional Study. Place and Duration of Study: Oncology Department, Combined Military Hospital (CMH), Rawalpindi Pakistan, from Dec2020 to Nov 2021. Methodology: This study was conducted on 145 female patients (>65 years) with breast cancer who were taking chemotherapy of any type and had undergone one cycle. All the study participants underwent detailed clinical evaluation by a consultant oncologist to assess the presence of various adverse effects of chemotherapy. In addition, the association of Anthracycline use,>3 months of treatment, low haemoglobin at baseline and abnormal liver functions at baseline were studied with adverse effects in the study participants. Results: The final analysis included one hundred forty-five elderly female patients with breast cancer receiving chemotherapy.The mean age of the patients was 6...
Mehran University Research Journal of Engineering and Technology, 2015
This paper parametrically optimizes the EDM (Electrical Discharge Machining) process in die sinki... more This paper parametrically optimizes the EDM (Electrical Discharge Machining) process in die sinking mode for material removal rate, surface roughness and edge quality of aluminum alloy Al-6061. The effect of eight parameters namely discharge current, pulse on-time, pulse off-time, auxiliary current, working time, jump time distance, servo speed and work piece hardness are investigated. Taguchi's orthogonal array L18 is employed herein for experimentation. ANOVA (Analysis of Variance) with F-ratio criterion at 95% confidence level is used for identification of significant parameters whereas SNR (Signal to Noise Ratio) is used for determination of optimum levels. Optimization obtained for Al-6061 with parametric combination investigated herein is validated by the confirmation run.
End Milling is a slot making operation which is extensively used in various industrial applicatio... more End Milling is a slot making operation which is extensively used in various industrial applications such as aerospace, automotive and dies molds making industry. Functioning of the parts manufactured in above mentioned industries is linked with the quality of the machined slots. This paper is aimed at investigating the quality of end milled slots taking into account different input process parameters whereas Titanium Nitride coated tools are employed for end milling operation. Quality of end milled slots is measured in terms of surface roughness and diameter error. Taguchi orthogonal array is used as the experimental design which resulted in better quality of end milled slots.
Influence of electrode material on quality of blind holes machined via electric discharge machine... more Influence of electrode material on quality of blind holes machined via electric discharge machine (die sinker)
An attempt has been made to design and fabricate a cricket ball launcher which can deliver balls ... more An attempt has been made to design and fabricate a cricket ball launcher which can deliver balls at speeds as high as 120 km/hr with the ability of bounce at different pitching positions. To fulfill this purpose we have used two vertically mounted wheels rotating one above the other at particular speeds in opposite directions to each other with a small amount of gap in between them through which balls are passed intermittently or continuously through a feeder. These two wheels are mounted on an inner frame which in turn is mounted on an outer frame through a pivot joint such that the inner frame pivots about the outer frame to facilitate different pitching positions. To power this system two DC motors of capacity 1/2 HP with speed 2400 rpm each have been used. Typically balls are thrown from a device using Motors, Mofsets, and Battery, 555timer, LCD Display and also mechanical aspects.
Abstract: WiMax, a broadband wireless access technology, is based on World Interoperability for M... more Abstract: WiMax, a broadband wireless access technology, is based on World Interoperability for Microwave access. It provides the last-mile solutions for different applications up to the maximum distance as compared to the other wireless technologies with better coverage and data rates. Basically, it is an IEEE 802.16 standard termed as a wireless MAN and the subset of this standard is 802.16a called as WiMax. It is developed by ETSI (European Telecommunication Standard Institute) offering data rate up-to 100Mbps and its transmission range is up-to 51km. WiMax, wireless MAN (Metropolitan Area Network), uses directional antennae to maximize the transmission range and coverage in LOS (Line of Sight) and NLOS (Non line of Sight). It uses both licensed and unlicensed frequency bands having spectrum range from 2GHz-66GHz. This innovative technology is used to provide broadband access with high data-rate for residential as well as enterprise use with low cost infrastructure. Both continuo...
Advances in Through-life Engineering Services, 2017
Reduction of warranty maintenance costs is a critical issue to the manufacturers of avionic produ... more Reduction of warranty maintenance costs is a critical issue to the manufacturers of avionic products. A method to reduce expected warranty costs is the determination of all components of financial losses to avionic product suppliers during the warranty period with further minimisation of these losses. This study interlinks the warranty, reliability and maintenance indicators of avionic products. Mathematical models are proposed for analysing and assessing financial costs to avionic system suppliers during the warranty period. The developed mathematical models consider the warranty period, reliability indicators with respect to permanent and intermittent failures, redundancy, number of spare parts, cost of restoration and transportation and penalties for exceeding the duration of warranty repair or replacement. Numerical examples illustrating the proposed models are provided.
Journal of Horticultural Science & Technology, 2021
Soil salinity is an important abiotic factor that adversely affects plant growth. In present stud... more Soil salinity is an important abiotic factor that adversely affects plant growth. In present study, response of rose (Rosa damascena) was evaluated to various NaCl salinity levels developed by irrigating saline water. Plants were irrigated with different salinities, viz. 0 (control), 50, 100, 150, 200 and 250 mM NaCl. After treatments application, plants were sampled, and relative growth rate (RGR) was calculated. Growth rates were significantly reduced as recorded for flower diameter, number of leaves per plant, number of shoots per plant, number of flowers per plant, number of petals per flower, fresh and dry weight of flower and petals. Results depicted that plant growth and yield significantly reduced with increase in salt concentration particularly when >150 mM NaCl was applied. Therefore, it is suggested that Rosa damascena may be best grown when salinity level of ≤150 mM and should not be grown in areas where salt concentrations are greater than 150 mM.
This paper proposes a mathematical model for assessing the trustworthiness of the system conditio... more This paper proposes a mathematical model for assessing the trustworthiness of the system condition prognosis. The set of mutually exclusive events at the time of predictive checking are analyzed. Correct and incorrect decisions correspond to events such as true-positive, false-positive, true-negative, and false-negative. General expressions for computing the probabilities of possible decisions when predicting the system condition at discrete times are proposed. The paper introduces the effectiveness indicators of predictive maintenance in the form of average operating costs, total error probability, and a posteriori probability of failure-free operation in the upcoming interval. We illustrate the developed approach by calculating the probabilities of correct and incorrect decisions for a specific stochastic deterioration process.
A novel iflavirus, tentatively named "Langfang leafhopper iflavirus" (LfLHV) was detected in leaf... more A novel iflavirus, tentatively named "Langfang leafhopper iflavirus" (LfLHV) was detected in leafhopper (Psammotettix alienus) by total RNA sequencing, and its genome sequence was confirmed by Sanger sequencing. The complete genome consisted of 10,700 nucleotides (nt) excluding the poly A tail and included one open reading frame (9,453 nt in length), encoding a polyprotein of 3,150 amino acids (aa). The nucleotide sequence of the complete genome was shared 44.1-53.3% identical, and the deduced amino acid sequence RNA-dependent RNA polymerase (RdRp) 22-74% identical to those of other iflaviruses. These values were all below the species demarcation threshold of 90%. Conserved motifs for structural proteins, helicase, protease, and RdRp were also similar to those in other iflaviruses. These results, as well as those of phylogenetic analysis based on the deduced amino acid sequences of the polyprotein and RdRp of LfLHV and other iflaviruses, indicate that the sequence represents a novel virus of the family Iflaviridae.
International Review of Management and Marketing, 2020
Globally, judicial sector regarding its relationship commitment has been discussed in few studies... more Globally, judicial sector regarding its relationship commitment has been discussed in few studies. In South-Asian context, service sector has been explored mostly with commercial industries like banks, restaurants and academic. However, professional industries like lawyers, doctors and brokers have rarely investigated by marketers to understand its relationship commitment with their clients considering their core antecedents. In such service industries, technical and functional service quality attributes along with communication effectives enhance client's satisfaction. Moreover, it examined trust and relationship quality of service provider that impact client-lawyer relationship commitment. Structured questionnaire was designed for collecting a sample of 220 clients who had/have encountered civil cases at district bar Faisalabad, Pakistan. Results of structured equation model shows that professional service quality and communication effectiveness promote relationship commitment among clients and professional lawyers. Also relationship quality mediates the relationship of service quality, communication effectiveness and relationship commitment. Limitations and future research directions are also discussed.
In this study, the generalized cost functions are proposed for choosing the optimal option of bre... more In this study, the generalized cost functions are proposed for choosing the optimal option of breakdown maintenance strategy of avionics systems. A mathematical model of avionics line replaceable unit (LRU) is developed. The model considers the main characteristics of the preflight checks and continuous testing of the LRU using built-in test equipment (BITE) in-flight. The equation for the mean time between unscheduled removals (MTBUR) is derived for an arbitrary and exponential distribution of time to failure. The cost functions are determined as the total operating costs separately for the warranty and post warranty period of operation. Different options of single-level, two-level and three-level maintenance are mathematically modeled and numerically analyzed for the warranty and post-warranty period of operation. The proposed analytical expressions take into account the trustworthiness of BITE, periodicity of preflight testing, cost of different maintenance operations, permanent ...
Background: In modern obstetrics alleviation of labour pains by simple, safe and effective means ... more Background: In modern obstetrics alleviation of labour pains by simple, safe and effective means presents a unique problem. Epidural analgesia has emerged as a popular and relatively safe option. This study was conducted to compare the efficacy of bupivacaine plus tramadol and bupivacaine plus fentanyl for ambulatory epidural analgesia in spontaneous vaginal delivery. Methods: This quasi-experimental study was carried out on 100 patients, ranging from 20 to 30 years age, having American Society of Anaesthesiology status I, primigravida, singleton with cephalic presentation, at PNS Shifa Hospital Karachi. The study was carried out from April 2007 to April 2008. Sampling technique was non-random convenient. Results: In Group-A pain after first dose was reduced at 10 minutes. But in Group B the action was delayed and analgesia was not adequate. After 20 min the analgesic effects in both groups were similar. Bupivacaine with fentanyl was associated with 96% patient satisfaction while bu...
Nanocarriers have provided the versatile platform for the delivery of various therapeutic and dia... more Nanocarriers have provided the versatile platform for the delivery of various therapeutic and diagnostic agents. Liposome, niosomes, polymeric and solid lipid nanoparticles are the most promising nanocarriers that have been entered in the clinical trials and become commercially available. However, each system has been associated with some problems that can be minimized by using the combinatorial approach of hybrid nanocarriers. These hybrid systems combine the benefits of different structural components to synergize the outcome of the therapy. In this chapter, the different types of hybrid nanocarriers have been described with particular emphasis on the brief rationale for the development of these hybrid nanocarriers along with different fabrication approaches with greater emphasize on the lipid polymer hybrid nanoparticles. A brief description factors governing the optimized response characteristics and their potential application of these hybrid nanoparticles are also presented.
Modern avionics can account for around 30% of the total cost of the aircraft. Therefore, it is es... more Modern avionics can account for around 30% of the total cost of the aircraft. Therefore, it is essential to reduce the operational cost of avionics during a lifetime. This article addresses the critical scientific problem of creating the appropriate maintenance models for digital avionics systems that significantly increase their operational effectiveness. In this research, we propose the lifecycle cost equations to select the best option for the maintenance of digital avionics. The proposed cost equations consider permanent failures, intermittent faults, and false-positives occurred during the flight. The lifecycle cost equations are determined for the warranty and the post-warranty interval of aircraft operation. We model several maintenance options for each period of service. The cost equations consider the characteristics of the permanent failures and intermittent faults, conditional probabilities of in-flight false-positive and true-positive as well as the cost of different mai...
Objective: To analyze the factors associated with adverse effects in elderly women receiving chem... more Objective: To analyze the factors associated with adverse effects in elderly women receiving chemotherapy for breast cancer. Study Design: Comparative Cross-sectional Study. Place and Duration of Study: Oncology Department, Combined Military Hospital (CMH), Rawalpindi Pakistan, from Dec2020 to Nov 2021. Methodology: This study was conducted on 145 female patients (>65 years) with breast cancer who were taking chemotherapy of any type and had undergone one cycle. All the study participants underwent detailed clinical evaluation by a consultant oncologist to assess the presence of various adverse effects of chemotherapy. In addition, the association of Anthracycline use,>3 months of treatment, low haemoglobin at baseline and abnormal liver functions at baseline were studied with adverse effects in the study participants. Results: The final analysis included one hundred forty-five elderly female patients with breast cancer receiving chemotherapy.The mean age of the patients was 6...
Mehran University Research Journal of Engineering and Technology, 2015
This paper parametrically optimizes the EDM (Electrical Discharge Machining) process in die sinki... more This paper parametrically optimizes the EDM (Electrical Discharge Machining) process in die sinking mode for material removal rate, surface roughness and edge quality of aluminum alloy Al-6061. The effect of eight parameters namely discharge current, pulse on-time, pulse off-time, auxiliary current, working time, jump time distance, servo speed and work piece hardness are investigated. Taguchi's orthogonal array L18 is employed herein for experimentation. ANOVA (Analysis of Variance) with F-ratio criterion at 95% confidence level is used for identification of significant parameters whereas SNR (Signal to Noise Ratio) is used for determination of optimum levels. Optimization obtained for Al-6061 with parametric combination investigated herein is validated by the confirmation run.
End Milling is a slot making operation which is extensively used in various industrial applicatio... more End Milling is a slot making operation which is extensively used in various industrial applications such as aerospace, automotive and dies molds making industry. Functioning of the parts manufactured in above mentioned industries is linked with the quality of the machined slots. This paper is aimed at investigating the quality of end milled slots taking into account different input process parameters whereas Titanium Nitride coated tools are employed for end milling operation. Quality of end milled slots is measured in terms of surface roughness and diameter error. Taguchi orthogonal array is used as the experimental design which resulted in better quality of end milled slots.
Influence of electrode material on quality of blind holes machined via electric discharge machine... more Influence of electrode material on quality of blind holes machined via electric discharge machine (die sinker)
An attempt has been made to design and fabricate a cricket ball launcher which can deliver balls ... more An attempt has been made to design and fabricate a cricket ball launcher which can deliver balls at speeds as high as 120 km/hr with the ability of bounce at different pitching positions. To fulfill this purpose we have used two vertically mounted wheels rotating one above the other at particular speeds in opposite directions to each other with a small amount of gap in between them through which balls are passed intermittently or continuously through a feeder. These two wheels are mounted on an inner frame which in turn is mounted on an outer frame through a pivot joint such that the inner frame pivots about the outer frame to facilitate different pitching positions. To power this system two DC motors of capacity 1/2 HP with speed 2400 rpm each have been used. Typically balls are thrown from a device using Motors, Mofsets, and Battery, 555timer, LCD Display and also mechanical aspects.
Abstract: WiMax, a broadband wireless access technology, is based on World Interoperability for M... more Abstract: WiMax, a broadband wireless access technology, is based on World Interoperability for Microwave access. It provides the last-mile solutions for different applications up to the maximum distance as compared to the other wireless technologies with better coverage and data rates. Basically, it is an IEEE 802.16 standard termed as a wireless MAN and the subset of this standard is 802.16a called as WiMax. It is developed by ETSI (European Telecommunication Standard Institute) offering data rate up-to 100Mbps and its transmission range is up-to 51km. WiMax, wireless MAN (Metropolitan Area Network), uses directional antennae to maximize the transmission range and coverage in LOS (Line of Sight) and NLOS (Non line of Sight). It uses both licensed and unlicensed frequency bands having spectrum range from 2GHz-66GHz. This innovative technology is used to provide broadband access with high data-rate for residential as well as enterprise use with low cost infrastructure. Both continuo...
Advances in Through-life Engineering Services, 2017
Reduction of warranty maintenance costs is a critical issue to the manufacturers of avionic produ... more Reduction of warranty maintenance costs is a critical issue to the manufacturers of avionic products. A method to reduce expected warranty costs is the determination of all components of financial losses to avionic product suppliers during the warranty period with further minimisation of these losses. This study interlinks the warranty, reliability and maintenance indicators of avionic products. Mathematical models are proposed for analysing and assessing financial costs to avionic system suppliers during the warranty period. The developed mathematical models consider the warranty period, reliability indicators with respect to permanent and intermittent failures, redundancy, number of spare parts, cost of restoration and transportation and penalties for exceeding the duration of warranty repair or replacement. Numerical examples illustrating the proposed models are provided.
Journal of Horticultural Science & Technology, 2021
Soil salinity is an important abiotic factor that adversely affects plant growth. In present stud... more Soil salinity is an important abiotic factor that adversely affects plant growth. In present study, response of rose (Rosa damascena) was evaluated to various NaCl salinity levels developed by irrigating saline water. Plants were irrigated with different salinities, viz. 0 (control), 50, 100, 150, 200 and 250 mM NaCl. After treatments application, plants were sampled, and relative growth rate (RGR) was calculated. Growth rates were significantly reduced as recorded for flower diameter, number of leaves per plant, number of shoots per plant, number of flowers per plant, number of petals per flower, fresh and dry weight of flower and petals. Results depicted that plant growth and yield significantly reduced with increase in salt concentration particularly when >150 mM NaCl was applied. Therefore, it is suggested that Rosa damascena may be best grown when salinity level of ≤150 mM and should not be grown in areas where salt concentrations are greater than 150 mM.
This paper proposes a mathematical model for assessing the trustworthiness of the system conditio... more This paper proposes a mathematical model for assessing the trustworthiness of the system condition prognosis. The set of mutually exclusive events at the time of predictive checking are analyzed. Correct and incorrect decisions correspond to events such as true-positive, false-positive, true-negative, and false-negative. General expressions for computing the probabilities of possible decisions when predicting the system condition at discrete times are proposed. The paper introduces the effectiveness indicators of predictive maintenance in the form of average operating costs, total error probability, and a posteriori probability of failure-free operation in the upcoming interval. We illustrate the developed approach by calculating the probabilities of correct and incorrect decisions for a specific stochastic deterioration process.
A novel iflavirus, tentatively named "Langfang leafhopper iflavirus" (LfLHV) was detected in leaf... more A novel iflavirus, tentatively named "Langfang leafhopper iflavirus" (LfLHV) was detected in leafhopper (Psammotettix alienus) by total RNA sequencing, and its genome sequence was confirmed by Sanger sequencing. The complete genome consisted of 10,700 nucleotides (nt) excluding the poly A tail and included one open reading frame (9,453 nt in length), encoding a polyprotein of 3,150 amino acids (aa). The nucleotide sequence of the complete genome was shared 44.1-53.3% identical, and the deduced amino acid sequence RNA-dependent RNA polymerase (RdRp) 22-74% identical to those of other iflaviruses. These values were all below the species demarcation threshold of 90%. Conserved motifs for structural proteins, helicase, protease, and RdRp were also similar to those in other iflaviruses. These results, as well as those of phylogenetic analysis based on the deduced amino acid sequences of the polyprotein and RdRp of LfLHV and other iflaviruses, indicate that the sequence represents a novel virus of the family Iflaviridae.
International Review of Management and Marketing, 2020
Globally, judicial sector regarding its relationship commitment has been discussed in few studies... more Globally, judicial sector regarding its relationship commitment has been discussed in few studies. In South-Asian context, service sector has been explored mostly with commercial industries like banks, restaurants and academic. However, professional industries like lawyers, doctors and brokers have rarely investigated by marketers to understand its relationship commitment with their clients considering their core antecedents. In such service industries, technical and functional service quality attributes along with communication effectives enhance client's satisfaction. Moreover, it examined trust and relationship quality of service provider that impact client-lawyer relationship commitment. Structured questionnaire was designed for collecting a sample of 220 clients who had/have encountered civil cases at district bar Faisalabad, Pakistan. Results of structured equation model shows that professional service quality and communication effectiveness promote relationship commitment among clients and professional lawyers. Also relationship quality mediates the relationship of service quality, communication effectiveness and relationship commitment. Limitations and future research directions are also discussed.
In this study, the generalized cost functions are proposed for choosing the optimal option of bre... more In this study, the generalized cost functions are proposed for choosing the optimal option of breakdown maintenance strategy of avionics systems. A mathematical model of avionics line replaceable unit (LRU) is developed. The model considers the main characteristics of the preflight checks and continuous testing of the LRU using built-in test equipment (BITE) in-flight. The equation for the mean time between unscheduled removals (MTBUR) is derived for an arbitrary and exponential distribution of time to failure. The cost functions are determined as the total operating costs separately for the warranty and post warranty period of operation. Different options of single-level, two-level and three-level maintenance are mathematically modeled and numerically analyzed for the warranty and post-warranty period of operation. The proposed analytical expressions take into account the trustworthiness of BITE, periodicity of preflight testing, cost of different maintenance operations, permanent ...
Background: In modern obstetrics alleviation of labour pains by simple, safe and effective means ... more Background: In modern obstetrics alleviation of labour pains by simple, safe and effective means presents a unique problem. Epidural analgesia has emerged as a popular and relatively safe option. This study was conducted to compare the efficacy of bupivacaine plus tramadol and bupivacaine plus fentanyl for ambulatory epidural analgesia in spontaneous vaginal delivery. Methods: This quasi-experimental study was carried out on 100 patients, ranging from 20 to 30 years age, having American Society of Anaesthesiology status I, primigravida, singleton with cephalic presentation, at PNS Shifa Hospital Karachi. The study was carried out from April 2007 to April 2008. Sampling technique was non-random convenient. Results: In Group-A pain after first dose was reduced at 10 minutes. But in Group B the action was delayed and analgesia was not adequate. After 20 min the analgesic effects in both groups were similar. Bupivacaine with fentanyl was associated with 96% patient satisfaction while bu...
Nanocarriers have provided the versatile platform for the delivery of various therapeutic and dia... more Nanocarriers have provided the versatile platform for the delivery of various therapeutic and diagnostic agents. Liposome, niosomes, polymeric and solid lipid nanoparticles are the most promising nanocarriers that have been entered in the clinical trials and become commercially available. However, each system has been associated with some problems that can be minimized by using the combinatorial approach of hybrid nanocarriers. These hybrid systems combine the benefits of different structural components to synergize the outcome of the therapy. In this chapter, the different types of hybrid nanocarriers have been described with particular emphasis on the brief rationale for the development of these hybrid nanocarriers along with different fabrication approaches with greater emphasize on the lipid polymer hybrid nanoparticles. A brief description factors governing the optimized response characteristics and their potential application of these hybrid nanoparticles are also presented.
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