Search results for: supercritical regime
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 824

Search results for: supercritical regime

254 Optimal Operation of Bakhtiari and Roudbar Dam Using Differential Evolution Algorithms

Authors: Ramin Mansouri

Abstract:

Due to the contrast of rivers discharge regime with water demands, one of the best ways to use water resources is to regulate the natural flow of the rivers and supplying water needs to construct dams. Optimal utilization of reservoirs, consideration of multiple important goals together at the same is of very high importance. To study about analyzing this method, statistical data of Bakhtiari and Roudbar dam over 46 years (1955 until 2001) is used. Initially an appropriate objective function was specified and using DE algorithm, the rule curve was developed. In continue, operation policy using rule curves was compared to standard comparative operation policy. The proposed method distributed the lack to the whole year and lowest damage was inflicted to the system. The standard deviation of monthly shortfall of each year with the proposed algorithm was less deviated than the other two methods. The Results show that median values for the coefficients of F and Cr provide the optimum situation and cause DE algorithm not to be trapped in local optimum. The most optimal answer for coefficients are 0.6 and 0.5 for F and Cr coefficients, respectively. After finding the best combination of coefficients values F and CR, algorithms for solving the independent populations were examined. For this purpose, the population of 4, 25, 50, 100, 500 and 1000 members were studied in two generations (G=50 and 100). result indicates that the generation number 200 is suitable for optimizing. The increase in time per the number of population has almost a linear trend, which indicates the effect of population in the runtime algorithm. Hence specifying suitable population to obtain an optimal results is very important. Standard operation policy had better reversibility percentage, but inflicts severe vulnerability to the system. The results obtained in years of low rainfall had very good results compared to other comparative methods.

Keywords: reservoirs, differential evolution, dam, Optimal operation

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253 Excited State Structural Dynamics of Retinal Isomerization Revealed by a Femtosecond X-Ray Laser

Authors: Przemyslaw Nogly, Tobias Weinert, Daniel James, Sergio Carbajo, Dmitry Ozerov, Antonia Furrer, Dardan Gashi, Veniamin Borin, Petr Skopintsev, Kathrin Jaeger, Karol Nass, Petra Bath, Robert Bosman, Jason Koglin, Matthew Seaberg, Thomas Lane, Demet Kekilli, Steffen Brünle, Tomoyuki Tanaka, Wenting Wu, Christopher Milne, Thomas A. White, Anton Barty, Uwe Weierstall, Valerie Panneels, Eriko Nango, So Iwata, Mark Hunter, Igor Schapiro, Gebhard Schertler, Richard Neutze, Jörg Standfuss

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Ultrafast isomerization of retinal is the primary step in a range of photoresponsive biological functions including vision in humans and ion-transport across bacterial membranes. We studied the sub-picosecond structural dynamics of retinal isomerization in the light-driven proton pump bacteriorhodopsin using an X-ray laser. Twenty snapshots with near-atomic spatial and temporal resolution in the femtosecond regime show how the excited all-trans retinal samples conformational states within the protein binding pocket prior to passing through a highly-twisted geometry and emerging in the 13-cis conformation. The aspartic acid residues and functional water molecules in proximity of the retinal Schiff base respond collectively to formation and decay of the initial excited state and retinal isomerization. These observations reveal how the protein scaffold guides this remarkably efficient photochemical reaction.

Keywords: bacteriorhodopsin, free-electron laser, retinal isomerization mechanism, time-resolved crystallography

Procedia PDF Downloads 248
252 Online Monitoring of Airborne Bioaerosols Released from a Composting, Green Waste Site

Authors: John Sodeau, David O'Connor, Shane Daly, Stig Hellebust

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This study is the first to employ the online WIBS (Waveband Integrated Biosensor Sensor) technique for the monitoring of bioaerosol emissions and non-fluorescing “dust” released from a composting/green waste site. The purpose of the research was to provide a “proof of principle” for using WIBS to monitor such a location continually over days and nights in order to construct comparative “bioaerosol site profiles”. Current impaction/culturing methods take many days to achieve results available by the WIBS technique in seconds.The real-time data obtained was then used to assess variations of the bioaerosol counts as a function of size, “shape”, site location, working activity levels, time of day, relative humidity, wind speeds and wind directions. Three short campaigns were undertaken, one classified as a “light” workload period, another as a “heavy” workload period and finally a weekend when the site was closed. One main bioaerosol size regime was found to predominate: 0.5 micron to 3 micron with morphologies ranging from elongated to elipsoidal/spherical. The real-time number-concentration data were consistent with an Andersen sampling protocol that was employed at the site. The number-concentrations of fluorescent particles as a proportion of total particles counted amounted, on average, to ~1% for the “light” workday period, ~7% for the “heavy” workday period and ~18% for the weekend. The bioaerosol release profiles at the weekend were considerably different from those monitored during the working weekdays.

Keywords: bioaerosols, composting, fluorescence, particle counting in real-time

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251 Lessons Learnt from a Patient with Pseudohyperkalaemia Secondary to Polycythaemia Rubra Vera in a Neuro-ICU Patient Resulting in Dangerous Interventions: Lessons Learnt on Patient Safety Improvement

Authors: Dinoo Kirthinanda, Sujani Wijeratne

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Pseudohyperkalaemia is a common benign in vitro phenomenon caused by the release of potassium ions (K+) from cells during specimen processing. Analysis of haemolysed blood samples for predominantly intracellular electrolytes may lead to re-investigation and potentially harmful interventions. We report a case of a 52-year male with myeloproliferative disease manifested as Polycythaemia Rubra Vera, Hypertension and hypertensive nephropathy with stage 3 chronic kidney disease admitted to Neuro-intensive care unit (NICU) with an intra-cerebral haemorrhage secondary to hypertensive bleed. His initial blood investigations showed hyperkalemia with serum K+ 6.2 mmol/L yet the bedside arterial blood gas analysis yielded K+ of 4.6 mmol/L. The patient was however given hyperkalemia regime twice based on venous electrolyte analysis. The discrepancy between the bedside electrolyte analysis using arterial blood and venous blood prompted further evaluation. The 12 lead Electrocardiogram showed U waves and sinus bradycardia corresponding to the serum K+ of 2.8 mmol/L on arterial blood gas analysis. Immediate K+ replacement ensured the patient did not develop life-threatening cardiac complications. Pseudohyperkalaemia may pose diagnostic challenges in the absence of detectable haemolysis and should be suspected in susceptible patients with normal Electrocardiogram and Glomerular Filtration Rate to avoid potentially life-threatening interventions. When in doubt, rapid analysis of arterial blood gas may be useful for accurate quantification of potassium.

Keywords: patient safety, pseudohyperkalaemia, haemolysis, myeloproliferative disorder

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250 Numerical investigation of Hydrodynamic and Parietal Heat Transfer to Bingham Fluid Agitated in a Vessel by Helical Ribbon Impeller

Authors: Mounir Baccar, Amel Gammoudi, Abdelhak Ayadi

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The efficient mixing of highly viscous fluids is required for many industries such as food, polymers or paints production. The homogeneity is a challenging operation for this fluids type since they operate at low Reynolds number to reduce the required power of the used impellers. Particularly, close-clearance impellers, mainly helical ribbons, are chosen for highly viscous fluids agitated in laminar regime which is currently heated through vessel wall. Indeed, they are characterized by high shear strains closer to the vessel wall, which causes a disturbing thermal boundary layer and ensures the homogenization of the bulk volume by axial and radial vortices. The hydrodynamic and thermal behaviors of Newtonian fluids in vessels agitated by helical ribbon impellers, has been mostly studied by many researchers. However, rarely researchers investigated numerically the agitation of yield stress fluid by means of helical ribbon impellers. This paper aims to study the effect of the Double Helical Ribbon (DHR) stirrers on both the hydrodynamic and the thermal behaviors of yield stress fluids treated in a cylindrical vessel by means of numerical simulation approach. For this purpose, continuity, momentum, and thermal equations were solved by means of 3D finite volume technique. The effect of Oldroyd (Od) and Reynolds (Re) numbers on the power (Po) and Nusselt (Nu) numbers for the mentioned stirrer type have been studied. Also, the velocity and thermal fields, the dissipation function and the apparent viscosity have been presented in different (r-z) and (r-θ) planes.

Keywords: Bingham fluid, Hydrodynamic and thermal behavior, helical ribbon, mixing, numerical modelling

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249 The Shrinking Nature of Parliamentary Immunity in Kenya: A Proposal for Judicial Restraint

Authors: Oscar Sang, Shadrack David Rotich

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Parliamentary immunity is grounded on the notion that parliaments need certain rights or immunities to ensure they can operate independently make fair and impartial decisions without capitulating to political pressure or intimidation. The 2013 election in Kenya marked an important milestone in the development of the law of parliamentary privilege. Such importance relates to the dramatic increase in the number of legislatures in the country from one unicameral parliament, to a bicameral national parliament and forty-seven other regional legislative assemblies. The increase in legislatures has resulted in a dramatic increase in political contestations which have led to legal wrangles. The judiciary in Kenya, once considered submissive, has been invited to arbitrate on various matters pitting individual rights and parliamentary privilege and have invalidated a number of legislative action. While judicial intervention is indeed necessary to ensure that legislatures in Kenya live true to the constitutional aspirations of the Kenyan people, certain judicial decisions have had an effect on eroding parliamentary immunity. This paper highlights a number of instances in which it could be argued that parliamentary privilege came under attack by the courts in Kenya. The paper aims to make a case that while Kenya’s progressive constitution necessitates the scope and extent of legislature’s immunities and privilege to be determined by the courts, it is important that courts exercise restraint in its review of legislative action. The paper makes the argument that unrestrained judicial action in Kenya on questions within the realm parliamentary privilege may undermine the functioning of Kenya’s legislatures. The paper explores approaches taken by a number of jurisdictions in establishing a proper balance between maintaining a viable parliamentary privilege regime in a rights-based constitutional system.

Keywords: Kenya, constitution, judicial restraint, parliamentary privilege

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248 Responding to the Mental Health Service Needs of Rural-to-Urban Migrant Workers in China: Current Situation and Future Directions

Authors: Yujun Liu, Maosheng Ran

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Background: Chinese rural-to-urban migrant workers’ mental health problems raise attentions from different social sectors. However, situation of present mental health services provided to this population has not been discovered. This study attempts to describe the current mental health service situation, identify the gaps and give the future directions based on the quantitative data. Methods: Questionnaire surveys were conducted among 2017 rural-to-urban migrant workers in 13 cities and 100 social work service organizations in 5 cities in 2014. Data was collected by face-to-face structured interview by trained interviewers. Findings: Migrant workers’ mental health status was not good. Compared to the severity of mental distress, mental health service for this population was lacking and insufficient, which accounted for only 14.4% of all services in our sample. And the group work and case work were the most frequently-used methods. By estimating a series of regression models, we revealed that life experiences and working conditions were significantly associated with migrant workers’ mental health status. Therefore, the macro social work practices aimed at this whole group were advocated to promote their mental wellbeing. That is, practitioners should not only focus on the improvement of migrant workers’ emotion management capacity, but also pay attention to raise awareness and improve their living and working condition; not only concentrate on the solving of individuals’ dilemma, but also promote gradual reformation of present labor regime and hukou system in China.

Keywords: Chinese rural-to-urban migrant workers, macro social work practice, mental health service needs, mental health status

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247 Comparing the Effects of Systemic Family Intervention on End Stage Renal Disease: Families of Different Modalities

Authors: Fenni Sim

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Background: The application of systemic family therapy approaches to community health cases have not gathered traction. In National Kidney Foundation, Singapore, the belief is that community support has great potential in helping End Stage Renal Failure (ESRF) patients manage the demands of their treatment regime, whether Hemodialysis (HD) or Peritoneal Dialysis(PD) and sustain them on the treatment. However, the current community support does not include family interventions and is largely nursing based. Although nursing support is well provided to patients, and their family members in issues related to treatment and compliance, complex family issues and dynamics arising from caregiver strain or pre-dialysis relationship strain might deter efforts in managing the challenges of the treatment. Objective: The objective of the study is to understand the potential scope of work provided by a social worker who is trained in systemic family therapy and the effects of these interventions. Methodology: 3 families on HD and 3 families on PD who have been receiving family intervention for the past 6 months would be chosen for the study. A qualitative interview would be conducted to review the effectiveness for the family. Scales such as SCORE-15, PHQ-9, and Zarit Burden were used to measure family functioning, depression, and caregiver’s burden for the families. Results: The research is still in preliminary phase. Conclusion: The study highlights the importance of family intervention for families with multiple stressors on different treatment modalities who might have different needs and challenges. Nursing support needs to be complemented with family-based support to manage complex family issues in order to achieve better health outcomes and improved family coping.

Keywords: complementing nursing support, end stage renal failure, healthcare, systemic approaches

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246 Inter-Country Parental Child Removal and Subsequent Custody Disputes in India: Need for Legislative Reforms

Authors: Pritam Kumar Ghosh

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The phenomenon of inter-country parental child removal and the protection of children against removal from lawful custody by their own parents has been a major issue over the last five decades. This occurs when parents take away their children during pending divorce and custody proceedings or in violation of pre-existing foreign or Indian custody orders through which they may have obtained visitation rights only after divorce but not permanent custody. Even though considerable efforts have been made by the Indian judiciary to resolve the issue, a lot is still left to be desired. A study of the spate of judicial decisions on the issue since 1970 reveals that judges have attempted to resolve the issue mainly through the application of the existing personal law regime and the principle of the best interest of the child. This has made the position of law extremely confusing. The existing precedential jurisprudence contains a wide variety of custody orders in the name of enforcement of the paramount consideration of the best interest and welfare of children. The problem is aggravated by the fact that India has decided not to accede to the Hague Abduction Convention of 1980, which is the main international instrument combating the issue. In this context, the paper discusses the reasons behind the rising instances of inter-country parental child removals. It then goes on to analyze the existing jurisprudence of international child custody disputes in India, which have come before courts post-removal of children from lawful custody. The paper concludes by suggesting essential reforms in the existing Indian legal framework governing the issue. In the process, the paper proposes new legislation for India governing inter-country parental child removals and subsequent custody disputes. The possible structure and content of this new law shall also be outlined as a part of the paper.

Keywords: custody, dispute, child removal, Hague convention

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245 Numerical Modeling of Film Cooling of the Surface at Non-Uniform Heat Flux Distributions on the Wall

Authors: M. V. Bartashevich

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The problem of heat transfer at thin laminar liquid film is solved numerically. A thin film of liquid flows down an inclined surface under conditions of variable heat flux on the wall. The use of thin films of liquid allows to create the effective technologies for cooling surfaces. However, it is important to investigate the most suitable cooling regimes from a safety point of view, in order, for example, to avoid overheating caused by the ruptures of the liquid film, and also to study the most effective cooling regimes depending on the character of the distribution of the heat flux on the wall, as well as the character of the blowing of the film surface, i.e., the external shear stress on its surface. In the statement of the problem on the film surface, the heat transfer coefficient between the liquid and gas is set, as well as a variable external shear stress - the intensity of blowing. It is shown that the combination of these factors - the degree of uniformity of the distribution of heat flux on the wall and the intensity of blowing, affects the efficiency of heat transfer. In this case, with an increase in the intensity of blowing, the cooling efficiency increases, reaching a maximum, and then decreases. It is also shown that the more uniform the heating of the wall, the more efficient the heat sink. A separate study was made for the flow regime along the horizontal surface when the liquid film moves solely due to external stress influence. For this mode, the analytical solution is used for the temperature at the entrance region for further numerical calculations downstream. Also the influence of the degree of uniformity of the heat flux distribution on the wall and the intensity of blowing of the film surface on the heat transfer efficiency was also studied. This work was carried out at the Kutateladze Institute of Thermophysics SB RAS (Russia) and supported by FASO Russia.

Keywords: Heat Flux, Heat Transfer Enhancement, External Blowing, Thin Liquid Film

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244 Voters' Acceptance of Anti-guardians' Narratives: Electoral Politics in Establishmentarian Democracies

Authors: Rai Mansoor Imtiaz

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Guardians in hybrid regimes fragment opposition parties and ban their political leaders, and disenfranchise their voters' political participation. When guardians in hybrid regimes are so powerful that they remain decisive on electoral politics of states, and have powers to ban political parties and their leadership, then "why do political parties backed by those powerful guardians lose elections" and "how do anti-establishment parties make electoral inroads at the local and national levels." These two questions are interrelated with the key research question of my research "why do people vote for political parties rejected by powerful guardians in establishmentarian democracies." Furthermore, this research question is important to be explored for two reasons. First, existing literature only reflects the electoral victories of opposition parties or defeats of military-sponsored parties (see Thailand and Turkey) but remains silent on political change that led the anti-military parties to win the elections. Second, why is it a case that people belonging to the countries where militaries remain popular among the public (see Turkey and Pakistan) have started putting their trust in anti-establishment politicians who criticise the military against their intervention in politics? For instance, in Pakistan, where commenting against the military is meant to comment against the state –– an anti-military narrative is getting popular support. The conceptual framework of hybrid states in this research relies on the concept of a 'reserved domain/tutelary body' (guardians of hybrid states). However, this research makes a case that hybrid states are not consolidated separate political entities but rather vacillated states that fluctuate between democratic and authoritarian practices. This paper, therefore, uses the term establishmentarian democracy as a subtype of the hybrid regime, which is more consolidated than a hybrid democracy.

Keywords: Guardians, Hybrid Regimes, Voters, Elections, Democracy, South Asia

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243 Effects of Inlet Filtration Pressure Loss on Single and Two-Spool Gas Turbine

Authors: Enyia James Diwa, Dodeye Ina Igbong, Archibong Archibong Eso

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Gas turbine operators have been faced with the dramatic financial setback resulting from compressor fouling. In a highly deregulated power industry where there is stiffness in the market competition, has made it imperative to improvise means of reducing maintenance cost in other to yield maximum profit. Compressor fouling results from the deposition of contaminants in the presence of oil and moisture on the compressor blade or annulus surfaces, which leads to a loss in flow capacity and compressor efficiency. These combined effects reduce power output, increase heat rate and cause creep life reduction. This paper also contains a model of two gas turbine engines via Cranfield University software known as TURBOMATCH, which is simulation software for detecting engine fouling rate. The model engines are of different configurations and capacities, and are operating in two different modes of constant output power and turbine inlet temperature for a two and three stage filter system. The idea is to investigate the more economically viable filtration systems by gas turbine users based on performance only. It has been demonstrated in the results that the two spool engine is a little more beneficial compared to the single spool. This is as a result of a higher pressure ratio of the two spools as well as the deceleration of the high-pressure compressor and high-pressure turbine speed in a constant TET. Meanwhile, the inlet filtration system was properly designed and balanced with a well-timed and economical compressor washing regime/scheme to control compressor fouling. The different technologies of inlet air filtration and compressor washing are considered and an attempt at optimization with respect to the cost of a combination of both control measures are made.

Keywords: inlet filtration, pressure loss, single spool, two spool

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242 Braiding Channel Pattern Due to Variation of Discharge

Authors: Satish Kumar, Spandan Sahu, Sarjati Sahoo, K. K. Khatua

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An experimental investigation has been carried out in a tilting flume of 2 m wide, 13 m long, and 0.3 m deep to study the effect of flow on the formation of braided channel pattern. Sediment flow is recirculated through the flume, which passes from the headgate to the sediment/water collecting tank through the tailgate. Further, without altering the geometry of the sand bed channel, the discharge is varied to study the effect of the formation of the braided pattern with time. Then the flow rate is varied to study the effect of flow on the formation of the braided pattern. Sediment transport rate is highly variable and was found to be a nonlinear function of flow rate, aspect ratio, longitudinal slope, and time. Total braided intensity (BIT) for each discharge case is found to be more than the active braided intensity (BIA). Both the parameters first increase and then decrease as the time progresses following a similar pattern for all the observed discharge cases. When the flow is increased, the movement of sediment also increases since the active braided intensity is found to adjust quickly. The measurement of velocity and boundary shear helps to study the erosion and sedimentation processes in the channel and formation of small meandering channels and then the braided channel for different discharge conditions of a sediment river. Due to regime properties of rivers, both total braided Intensity and active braided intensity become stable for a given channel and flow conditions. In the present case, the trend of the ratio of BIA to BIT is found to be asymptotic against the time with a value of 0.4. After the particular time elapses off the flow, new small channels are also found to be formed with changes in the sinuosity of the active channels, thus forming the braided network. This is due to the continuous erosion and sedimentation processes occurring for the flow process for the flow and sediment conditions.

Keywords: active braided intensity, bed load, sediment transport, shear stress, total braided intensity

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241 Alternative (In)Security: Using Photovoice Research Methodology to Explore Refugee Anxieties in Lebanon

Authors: Jessy Abouarab

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For more than half a century, international norms related to refugee security and protection have proliferated, yet their role in alleviating war’s negative impacts on human life remains limited. The impact of refugee-security processes often manifests asymmetrically within populations. Many issues and people get silenced due to narrow security policies that focus either on abstract threat containment and refugee control or refugee protection and humanitarian aid. (In)security practices are gendered and experienced. Examining the case study of Syrian refugees in Lebanon, this study explores the gendered impact of refugee security mechanisms on local realities. A transnational feminist approach will be used to position this research in relation to existing studies in the field of security and the refugee-protection regime, highlighting the social, cultural, legal, and political barriers to gender equality in the areas of violence, rights, and social inclusion. Through Photovoice methodology, the Syrian refugees’ (in)securities in Lebanon were given visibility by enabling local volunteers to record and reflect their realities through pictures, at the same time voice the participants’ anxieties and recommendations to reach normative policy change. This Participatory Action Research approach helped participants observe the structural barriers and lack of culturally inclusive refugee services that hinder security, increase discrimination, stigma, and poverty. The findings have implications for a shift of the refugee protection mechanisms to a community-based approach in ways that extend beyond narrow security policies that hinder women empowerment and raise vulnerabilities such as gendered exploitation, abuse, and neglect.

Keywords: gender, (in)security, Lebanon, refugee, Syrian refugees, women

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240 Vertical Distribution of the Monthly Average Values of the Air Temperature above the Territory of Kakheti in 2012-2017

Authors: Khatia Tavidashvili, Nino Jamrishvili, Valerian Omsarashvili

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Studies of the vertical distribution of the air temperature in the atmosphere have great value for the solution of different problems of meteorology and climatology (meteorological forecast of showers, thunderstorms, and hail, weather modification, estimation of climate change, etc.). From the end of May 2015 in Kakheti after 25-year interruption, the work of anti-hail service was restored. Therefore, in connection with climate change, the need for the detailed study of the contemporary regime of the vertical distribution of the air temperature above this territory arose. In particular, the indicated information is necessary for the optimum selection of rocket means with the works on the weather modification (fight with the hail, the regulation of atmospheric precipitations, etc.). Construction of the detailed maps of the potential damage distribution of agricultural crops from the hail, etc. taking into account the dimensions of hailstones in the clouds according to the data of radar measurements and height of locality are the most important factors. For now, in Georgia, there is no aerological probing of atmosphere. To solve given problem we processed information about air temperature profiles above Telavi, at 27 km above earth's surface. Information was gathered during four observation time (4, 10, 16, 22 hours with local time. After research, we found vertical distribution of the average monthly values of the air temperature above Kakheti in ‎2012-2017 from January to December. Research was conducted from 0.543 to 27 km above sea level during four periods of research. In particular, it is obtained: -during January the monthly average air temperature linearly diminishes with 2.6 °C on the earth's surface to -57.1 °C at the height of 10 km, then little it changes up to the height of 26 km; the gradient of the air temperature in the layer of the atmosphere from 0.543 to 8 km - 6.3 °C/km; height of zero isotherm - is 1.33 km. -during July the air temperature linearly diminishes with 23.5 °C to -64.7 °C at the height of 17 km, then it grows to -47.5 °C at the height of 27 km; the gradient of the air temperature of - 6.1 °C/km; height of zero isotherm - is 4.39 km, which on 0.16 km is higher than in the sixties of past century.

Keywords: hail, Kakheti, meteorology, vertical distribution of the air temperature

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239 Adaptable Regulatory Oversight and Safety Awareness Regime: An Experience-Based Contribution Towards Sustainability in a Changing Railway Environment

Authors: Peaceman Sopazi, Mabila Mathebula, John Smallwood

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Recent health and safety (H&S) concerns and their resultant impact on railway operations, namely, the severe acute respiratory syndrome (SARS) or collectively known as SARS-CoV-2 (Covid-19) pandemic and the Fourth Industrial Revolution (4IR), which have dominated public discourse, brought into question as to whether, or not, some aspects of how we have so far managed safety oversight as railway regulatory bodies and operators will remain relevant in a changing railway environment. Railway practitioners have generally found themselves between a proverbial rock and a hard place by being confronted by emerging challenges which have brought along great opportunities for sustainability. As witnesses and participants to the progressively introduced railway safety management, and transformation regimes, this paper attempts to share gathered field experience on adaptable regulatory oversight and safety awareness. The discourse is approached from a South African context but also with an informed perspective of what seems to work and what usually does not. The authors share their own multi and transdisciplinary experience coupled with insights they have gained as researchers of global trends in general safety management and specific aspects of railway safety management, for sustainability. In addition to sharing a largely experience-based methodology for survival, suggestions are offered for consideration as a way of keeping the railway safety management discourse alive as practitioners navigate a new path which is shrouded in a cloud of untold uncertainty. The authors further believe that the right timing for the implementation of the proposed suggestions in this paper will produce beneficial outcomes. Finally, the paper will identify areas that are still open for further investigation for and by researchers and practitioners alike.

Keywords: health & safety management, safety awareness, railway safety management, railway systems sustainability

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238 Bioprospecting for Indigenous Ruderal Plants with Potentials for Phytoremediation of Soil Heavy Metals in the Southern Guinea Savanna of North Western Nigeria

Authors: Sunday Paul Bako, Augustine Uwanekwu Ezealor, Yahuza Tanimu

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In a study to evaluate the response of indigenous ruderal plants to the metal deposition regime imposed by anthropogenic modification in the Southern Guinea Savanna of north Western Nigeria during the dry and wet seasons, herbaceous plants and samples of soils were collected in three 5m by 5m quadrats laid around the environs of the Kaduna Refinery and Petrochemical Company and the banks of River Kaduna. Heavy metal concentration (Cd, Ni, Cr, Cu, Fe, Mn and Zn) in soil and plant samples was determined using Energy Dispersive X-ray Fluorescence. Concentrations of heavy metals in soils were generally observed to be higher during the wet season in both locations although the differences were not statistically significant (P > 0.05). Concentrations of Cd, Zn, Cr, Cu and Ni in all the plants observed were found to be below levels described as phytotoxic to plants. However, above ‘normal’ concentrations of Cr was observed in most of the plant species sampled. The concentrations of Cr, Cu, Ni and Zn in soils around the KRPC and RKB were found to be above the acceptable limits. Although no hyper accumulator plant species was encountered in this study, twenty (20) plant species were identified to have high bioconcentration (BCF > 1.0) of Cd and Cu, which indicated tolerance of these plants to excessive or phytotoxic concentrations of these metals. In addition, they generally produce high above ground biomass, due to rapid vegetative growth. These are likely species for phytoextraction. Elevated concentration of metals in both soil and plant materials may cause a decrease in biodiversity due to direct toxicity. There are also risks to humans and other animals due to bioaccumulation across the food chain. There are further possibilities of further evaluating and genetically improving metal tolerance traits in some of these plant species in relation to their potential use in phytoremediation programmes in metal polluted sites.

Keywords: bioprospecting, phytoremediation, heavy metals, Nigeria

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237 Directors’ Liability for Losses Incurred in the Management of PT Merpati Nusantara Airlines, Persero

Authors: Eny Suastuti

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This paper is about state’s capital equity in establishing State-owned Company (PT Merpati Persero). Under private law regime, PT Merpati Persero equity is a state asset allocated separately from the State Budget. Consequently, it is no longer a state asset; rather, it becomes a part of company assets. The adoption of Act No. 17 of 2003 on State Finance, Act No. 31 of 1999, which is amended by Act No. 20 of 2001 on Eradication of Corrupt Practices, Act No. 15 of 2004 on Auditing, Management, and Accountability of State Finance, and Act No. 15 of 2006 Audit Board raises legal issues of whether State-owned Company’s (PT Merpati Persero) loss may be deemed as loss on state finance made by the Directors of PT Merpati Persero, which implication leads to corrupt practices conducted by the Directors. The principle of civil law states that state assets are separated from the state budget is not a government asset. Therefore the case of a lease agreement 2 (two) units of Boeing 737-400 and Boeing 737-500 between PT Merpati Nusantara Airlines with companies Third Stone Aircraft Leasing Group (TALG) the United States cannot be prosecuted under Articles 2 and 3 of Act No. 31 of 1999 Jo Act No. 20 of 2001 on Eradication of Corrupt Practices (Law PTPK). From this paper, three things are found. First, state’s capital equity, which has been allocated separately from state assets in establishing the PT Merpati Perserois not state asset; rather, it is company’s asset. Second, in the case of mismanagement leading to company loss, the Directors of PT Merpati Persero may not be charged with committing corrupt practice as prescribed in Articles 2 and 3 of Corrupt Practices Eradication Law. Third, misperception has been made by judicial practices since the courts consider loss in certain transaction made by Directors of PT Merpati Persero to be loss of state finance whose implication is applicability of Articles 2 and 3 of Corrupt Practices Eradication Law.

Keywords: corrupt practice, loss, state's capital equity, state finance (PT Merpati Persero)

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236 All-Optical Gamma-Rays and Positrons Source by Ultra-Intense Laser Irradiating an Al Cone

Authors: T. P. Yu, J. J. Liu, X. L. Zhu, Y. Yin, W. Q. Wang, J. M. Ouyang, F. Q. Shao

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A strong electromagnetic field with E>1015V/m can be supplied by an intense laser such as ELI and HiPER in the near future. Exposing in such a strong laser field, laser-matter interaction enters into the near quantum electrodynamics (QED) regime and highly non-linear physics may occur during the laser-matter interaction. Recently, the multi-photon Breit-Wheeler (BW) process attracts increasing attention because it is capable to produce abundant positrons and it enhances the positron generation efficiency significantly. Here, we propose an all-optical scheme for bright gamma rays and dense positrons generation by irradiating a 1022 W/cm2 laser pulse onto an Al cone filled with near-critical-density plasmas. Two-dimensional (2D) QED particle-in-cell (PIC) simulations show that, the radiation damping force becomes large enough to compensate for the Lorentz force in the cone, causing radiation-reaction trapping of a dense electron bunch in the laser field. The trapped electrons oscillate in the laser electric field and emits high-energy gamma photons in two ways: (1) nonlinear Compton scattering due to the oscillation of electrons in the laser fields, and (2) Compton backwardscattering resulting from the bunch colliding with the reflected laser by the cone tip. The multi-photon Breit-Wheeler process is thus initiated and abundant electron-positron pairs are generated with a positron density ~1027m-3. The scheme is finally demonstrated by full 3D PIC simulations, which indicate the positron flux is up to 109. This compact gamma ray and positron source may have promising applications in future.

Keywords: BW process, electron-positron pairs, gamma rays emission, ultra-intense laser

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235 Influence of Water Reservoir Parameters on the Climate and Coastal Areas

Authors: Lia Matchavariani

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Water reservoir construction on the rivers flowing into the sea complicates the coast protection, seashore starts to degrade causing coast erosion and disaster on the backdrop of current climate change. The instruments of the impact of a water reservoir on the climate and coastal areas are its contact surface with the atmosphere and the area irrigated with its water or humidified with infiltrated waters. The Black Sea coastline is characterized by the highest ecological vulnerability. The type and intensity of the water reservoir impact are determined by its morphometry, type of regulation, level regime, and geomorphological and geological characteristics of the adjoining area. Studies showed the impact of the water reservoir on the climate, on its comfort parameters is positive if it is located in the zone of insufficient humidity and vice versa, is negative if the water reservoir is found in the zone with abundant humidity. There are many natural and anthropogenic factors determining the peculiarities of the impact of the water reservoir on the climate, which can be assessed with maximum accuracy by the so-called “long series” method, which operates on the meteorological elements (temperature, wind, precipitations, etc.) with the long series formed with the stationary observation data. This is the time series, which consists of two periods with statistically sufficient duration. The first period covers the observations up to the formation of the water reservoir and another period covers the observations accomplished during its operation. If no such data are available, or their series is statistically short, “an analog” method is used. Such an analog water reservoir is selected based on the similarity of the environmental conditions. It must be located within the zone of the designed water reservoir, under similar environmental conditions, and besides, a sufficient number of observations accomplished in its coastal zone.

Keywords: coast-constituent sediment, eustasy, meteorological parameters, seashore degradation, water reservoirs impact

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234 Viscoelastic Properties of Sn-15%Pb Measured in an Oscillation Test

Authors: Gerardo Sanjuan Sanjuan, Ángel Enrique Chavéz Castellanos

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The knowledge of the rheological behavior of partially solidified metal alloy is an important issue when modeling and simulation of die filling in semisolid processes. Many experiments for like steady state, the step change in shear rate tests, shear stress ramps have been carried out leading that semi-solid alloys exhibit shear thinning, thixotropic behavior and yield stress. More advanced investigation gives evidence some viscoelastic features can be observed. The viscoelastic properties of materials are determinate by transient or dynamic methods; unfortunately, sparse information exists about oscillation experiments. The aim of this present work is to use small amplitude oscillatory tests for knowledge properties such as G´ and G´´. These properties allow providing information about materials structure. For this purpose, we investigated tin-lead alloy (Sn-15%Pb) which exhibits a similar microstructure to aluminum alloys and is the classic alloy for semisolid thixotropic studies. The experiments were performed with parallel plates rheometer AR-G2. Initially, the liquid alloy is cooled down to the semisolid range, a specific temperature to guarantee a constant fraction solid. Oscillation was performed within the linear viscoelastic regime with a strain sweep. So, the loss modulus G´´, the storage modulus G´ and the loss angle (δ) was monitored. In addition a frequency sweep at a strain below the critical strain for characterized its structure. This provides more information about the interactions among solid particles on a liquid matrix. After testing, the sample was removed then cooled, sectioned and examined metallographically. These experiments demonstrate that the viscoelasticity is sensitive to the solid fraction, and is strongly influenced by the shape and size of particles solid.

Keywords: rheology, semisolid alloys, thixotropic, viscoelasticity

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233 Formulating Anti-Insurgency Curriculum Conceptual and Design Principles for Translation into Anti-Terrorist Curriculum Framework for Muslim Secondary Schools

Authors: Saheed Ahmad Rufai

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The growing nature of insurgencies in their various forms in the Muslim world is now of great concern to both the leadership and the citizenry. The high sense of insecurity occasioned by the unpleasant experience has in fact attained an alarming rate in the estimation of both Muslims and non-Muslims alike. Consequently, the situation began to attract contributions from scholars and researchers in security-related fields of humanities and social sciences. However, there is little evidence of contribution to the discourse and the scholarship involved by scholars in the field of education. The purpose of this proposed study is to contribute an education dimension to the growing scholarship on the subject. The study which is situated in the broad scholarship of curriculum making and grounded in both the philosophical and sociological foundations of the curriculum, employs a combination of curriculum criticism and creative synthesis, as methods, in reconstructing Muslim schools’ educational blueprint. The significance of the proposed study lies in its potential to contribute a useful addition to the scholarship of curriculum construction in the context of the Muslim world. The significance also lies in its potential to offer an ameliorative proposal over unnecessary insurgency or militancy thereby paving the way for the enthronement of a regime characterized by peaceful, harmonious and tranquil co-existence among people of diverse orientations and ideological persuasions in the Muslim world. The study is restricted to only the first two stages of curriculum making namely the formulation of philosophy which concerns the articulation of objectives, aims, purposes, goals, and principles, as well as the second stage which covers the translation of such principles to an anti-insurgency secondary school curriculum for the Muslim world.

Keywords: education for conflict resolution, anti-insurgency curriculum principles, peace education, anti-terrorist curriculum framework, curriculum for Muslim secondary schools

Procedia PDF Downloads 224
232 Paleogene Syn-Rift Play Identification in Palembang Sub-Basin, South Sumatera, Indonesia

Authors: Perdana Rakhmana Putra, Hansen Wijaya, Sri Budiyani, Muhamad Natsir, Alexis badai Samudra

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The Palembang Sub-Basin (PSB) located in southern part of South Sumatera basin (SSB) consist of half-graben complex trending N-S to NW-SE. These geometries are believe as an impact of strike-slip regime developed in Eocene-Oligocene. Generally, most of the wells in this area produced hydrocarbon from late stage of syn-rift sequences called Lower Talang Akar (LTAF) and post-rift sequences called Batu Raja Formation (BRF) and drilled to proved hydrocarbon on structural trap; three-way dip anticline, four-way dip anticline, dissected anticline, and stratigraphy trap; carbonate build-up and stratigraphic pinch out. Only a few wells reached the deeper syn-rift sequences called Lahat Formation (LAF) and Lemat Formation (LEF). The new interpretation of subsurface data was done by the tectonostratigraphy concept and focusing on syn-rift sequence. Base on seismic characteristic on basin centre, it divided into four sequences: pre-rift sequence, rift initiation, maximum rift and late rift. These sequences believed as a new exploration target on PSB mature basin. This paper will demonstrate the paleo depositional setting during Paleogene and exploration play concept of syn-rift sequence in PSB. The main play for this area consists of stratigraphic and structure play, where the stratigraphic play is Eocene-Oligocene sediment consist of LAF sandstone, LEF-Benakat formation, and LAF with pinch-out geometry. The pinch-out, lenses geometry and on-lap features can be seen on the seismic reflector and formed at the time of the syn-rift sequence. The structural play is dominated by a 3 Way Dip play related to reverse fault trap.

Keywords: syn-rift, tectono-stratigraphy, exploration play, basin center play, south sumatera basin

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231 Study of the Hydrochemical Composition of Canal, Collector-Drainage and Ground Waters of Kura-Araz Plain and Modeling by GIS Method

Authors: Gurbanova Lamiya

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The Republic of Azerbaijan is considered a region with limited water resources, as up to 70% of surface water is formed outside the country's borders, and most of its territory is an arid (dry) climate zone. It is located at the lower limit of transboundary flows, which is the weakest source of natural water resources in the South Caucasus. It is essential to correctly assess the quality of natural, collector-drainage and groundwater of the area and their suitability for irrigation in order to properly carry out land reclamation measures, provide the normal water-salt regime, and prevent repeated salinization. Through the 141-km-long main Mil-Mugan collector, groundwater, household waste, and floodwaters generated during floods and landslides are poured into the Caspian Sea. The hydrochemical composition of the samples taken from the Sabir irrigation canal passing through the center of the Kura-Araz plain, the Main Mil-Mugan Collector, and the groundwater of the region, which we chose as our research object, were studied and the obtained results were compared by periods. A model is proposed that allows for a complete visualization of the primary materials collected for the study area. The practical use of the established digital model provides all possibilities. The practical use of the established digital model provides all possibilities. An extensive database was created with the ArcGis 10.8 package, using publicly available LandSat satellite images as primary data in addition to ground surveys to build the model. The principles of the construction of the geographic information system of modern GIS technology were developed, the boundary and initial condition of the research area were evaluated, and forecasts and recommendations were given.

Keywords: irrigation channel, groundwater, collector, meliorative measures

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230 Magneto-Hydrodynamic Mixed Convective Fluid Flow through Two Parallel Vertical Plates Channel with Hall, Chemical Reaction, and Thermal Radiation Effects

Authors: Okuyade Ighoroje Wilson Ata

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Magneto-hydrodynamic mixed convective chemically reacting fluid flow through two parallel vertical plates channel with Hall, radiation, and chemical reaction effects are examined. The fluid is assumed to be chemically reactive, electrically conducting, magnetically susceptible, viscous, incompressible, and Newtonian; the plates are porous, electrically conductive, and heated to a high-temperature regime to generate thermal rays. The flow system is highly interactive, such that cross/double diffusion is present. The governing equations are partial differential equations transformed into ordinary differential equations using similarity transformation and solved by the method of Homotopy Perturbation. Expressions for the concentration, temperature, velocity, Nusselt number, Sherwood number, and Wall shear stress are obtained, computed, and presented graphically and tabularly. The analysis of results shows, amongst others, that an increase in the Raleigh number increases the main velocity and temperature but decreases the concentration. More so, an increase in chemical reaction rate increases the main velocity, temperature, rate of heat transfer from the terminal plate, the rate of mass transfer from the induced plate, and Wall shear stress on both the induced and terminal plates, decreasing the concentration, and the mass transfer rate from the terminal plate. Some of the obtained results are benchmarked with those of existing literature and are in consonance.

Keywords: chemical reaction, hall effect, magneto-hydrodynamic, radiation, vertical plates channel

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229 Corporate Governance in Higher Education: A South African Perspective

Authors: Corlia van der Walt, Michele K. Havenga

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The study considers corporate governance regulation and practice in South African higher education institutions and makes recommendations for the improvement of current governance practices in this sector. The development of corporate governance principles and practices in South Africa, culminating in the King IV Report on Corporate Governance which was launched in November 2016, is discussed. King IV enjoys international recognition as a progressive corporate governance instrument. It was necessitated by the fundamental changes in business and society nationally and globally, as well as by the significant changes to South African company law introduced by new legislation. Corporate governance and the corporate form are narrowly associated, but there is general recognition that the principles of ethical and effective leadership are not restricted to corporations. Thus King IV was drafted with the express aim that it should apply to all organisations, regardless of their form of incorporation, and the report includes specific sector supplements in support of this aspiration. The South African higher education sector has of late been under intense scrutiny, and a few universities have been placed under administration because of poor governance practices. Universities have also been severely impacted by the consequences of what is generally known as ‘#FeesmustFall’, a student led protest movement initially aimed against the increase of fees at public universities, but which rapidly expanded to also include other concerns. It was clearly necessary to revisit corporate governance policy and practice in the sector. The review of the current higher education governance regime in light of the King IV recommendations, lessons from company law regarding the entrenchment and enforcement of corporate governance principles, and a comparison of higher education governance practices in selected other jurisdictions led to recommendations for the improvement of governance practices in South African higher education. It is further suggested that a sector supplement for higher education institutions may provide additional clarity. Some of the recommendations may be of comparative value for international higher education governance.

Keywords: committees, corporate governance, ethical leadership, higher education institutions, integrated reporting, King IV, sector supplements, sustainability

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228 An Entrepreneurial Culture Led by Creativity and Innovation: Challenges and Competencies for Sri Lanka as a Middle Income Country

Authors: Tissa Ravinda Perera

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An open economic policy was introduced by Sri Lanka in 1977, before many other countries in Asia to align her economy to world economic trends and it was affected indigenous businesses since they had to compete with foreign products, processes, technology, innovations and businesses. The year 2010 was a milestone in Sri Lankan history to achieve the developmental goals when Foxbuisness rated Sri Lanka as the best performing global economy. However, Sri Lanka missed her chances of achieving development with the political and social chaos, consequent the regime change in 2015. This paper argues that to support the development of the country, Sri Lanka must develop an entrepreneurial culture. In this endeavor, creativity and innovation will play a pivotal role to achieve the desired level of development. In this study, it was used secondary data from various local and international sources to understand and explore the existing scenario of Sri Lankan economy, state of entrepreneurial culture and innovation, and challenges and competencies for the development of an entrepreneurial culture in Sri Lanka. The data was collected from secondary sources were depicted in tables in this paper in a meaningful manner. Based on the tables many findings were aroused and conclusions were made to support the argument in this paper. This paper revealed that the development of an entrepreneurial culture has to be associated with creativity and innovation to gain a competitive advantage over the development strategies of other countries. It is exposed that an entrepreneurial culture will help minorities, women and underprivileged societies to empower themselves. This product will help to confront and manage youth unrest which has created anarchy in the country from time to time. Throughout this paper, it was highlighted the past, present and future scenario of Sri Lankan economy along with modification to be done to it through the development of an entrepreneur culture in light of innovation and creativity to achieve the desired level of development.

Keywords: economy, industry, creativity, innovation, entrepreneurship, entrepreneurial culture

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227 Quantifying Late Cenozoic Out‐of‐Sequence Thrusting at Chaura, Sutlej Valley, Himachal Pradesh, India

Authors: Rajkumar Ghosh

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Out-of-sequence thrusts (OOST) are reported at different geographic locations with various local names along Siwalik Himalaya (SH), Lesser Himalaya (LH), Higher Himalaya (HH) from Bhutan, India, Nepal, and Pakistan Himalayan range. Most of OOSTs have been identified within the upper LH, and the lower HH based on geochronological age jump across. These thrusts activated from Late Miocene to recent. The Chaura Thrust (CT) was deciphered from age jump of Apatite Fission Track (AFT) and considered as blind thrust base on variable exhumation rates in Chaura region, Satluj river valley, Himachal Pradesh. CT is located north of Jhakri Thrust (JhT) and is also differently identified as Sarahan thrust (ST). Structural documentation from the rocks near the OOST in Chaura was not so far done. Detail structural study of the Jeori Group of rocks was carried out in this study to understand the manifestation of the Chaura thrust and associated structures in meso- to micro-scale. Box fold, scar fold, kink fold, crenulation cleavages, and boudins are developed in the Chaura region. These structures usually do not indicate shear sense. When studied under an optical microscope, the Chaura samples reveal that the mica fish are usually lenticular with aspect ratio (R) varying from 6–11 and inclination angle (α) from 15–40°. According to ‘R’ and ‘α’, elongated sigmoid shaped mica fish and parallelogram shaped mica fish were also documented. Asymmetric mica fish demonstrate top-to-S/SW ductile shear, which is similar as that of Chaura thrust. Grain boundary migration (GBM) structures in quartzo-feldspathic grains from Jeori Group of rocks indicate deformation temperature ranging from 400 to 650°C. This can indicate that the OOST at Chaura, i.e., the Chaura Thrust, underwent thrusting in the ductile regime.

Keywords: out-of-sequence thrust, chaura thrust, sarahan thrust, jakhri thrust, higher himalaya, s/c- fabric

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226 Flow Field Analysis of Different Intake Bump (Compression Surface) Configurations on a Supersonic Aircraft

Authors: Mudassir Ghafoor, Irsalan Arif, Shuaib Salamat

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This paper presents modeling and analysis of different intake bump (compression surface) configurations and comparison with an existing supersonic aircraft having bump intake configuration. Many successful aircraft models have shown that Diverter less Supersonic Inlet (DSI) as compared to conventional intake can reduce weight, complexity and also maintenance cost. The research is divided into two parts. In the first part, four different intake bumps are modeled for comparative analysis keeping in view the consistency of outer perimeter dimensions of fighter aircraft and various characteristics such as flow behavior, boundary layer diversion and pressure recovery are analyzed. In the second part, modeled bumps are integrated with intake duct for performance analysis and comparison with existing supersonic aircraft data is carried out. The bumps are named as uniform large (Config 1), uniform small (Config 2), uniform sharp (Config 3), non-uniform (Config 4) based on their geometric features. Analysis is carried out at different Mach Numbers to analyze flow behavior in subsonic and supersonic regime. Flow behavior, boundary layer diversion and Pressure recovery are examined for each bump characteristics, and comparative study is carried out. The analysis reveals that at subsonic speed, Config 1 and Config 2 give similar pressure recoveries as diverterless supersonic intake, but difference in pressure recoveries becomes significant at supersonic speed. It was concluded from research that Config 1 gives better results as compared to Config 3. Also, higher amplitude (Config 1) is preferred over lower (Config 2 and 4). It was observed that maximum height of bump is preferred to be placed near cowl lip of intake duct.

Keywords: bump intake, boundary layer, computational fluid dynamics, diverter-less supersonic inlet

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225 Investigation of the Material Behaviour of Polymeric Interlayers in Broken Laminated Glass

Authors: Martin Botz, Michael Kraus, Geralt Siebert

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The use of laminated glass gains increasing importance in structural engineering. For safety reasons, at least two glass panes are laminated together with a polymeric interlayer. In case of breakage of one or all of the glass panes, the glass fragments are still connected to the interlayer due to adhesion forces and a certain residual load-bearing capacity is left in the system. Polymer interlayers used in the laminated glass show a viscoelastic material behavior, e.g. stresses and strains in the interlayer are dependent on load duration and temperature. In the intact stage only small strains appear in the interlayer, thus the material can be described in a linear way. In the broken stage, large strains can appear and a non-linear viscoelasticity material theory is necessary. Relaxation tests on two different types of polymeric interlayers are performed at different temperatures and strain amplitudes to determine the border to the non-linear material regime. Based on the small-scale specimen results further tests on broken laminated glass panes are conducted. So-called ‘through-crack-bending’ (TCB) tests are performed, in which the laminated glass has a defined crack pattern. The test set-up is realized in a way that one glass layer is still able to transfer compressive stresses but tensile stresses have to be transferred by the interlayer solely. The TCB-tests are also conducted under different temperatures but constant force (creep test). Aims of these experiments are to elaborate if the results of small-scale tests on the interlayer are transferable to a laminated glass system in the broken stage. In this study, limits of the applicability of linear-viscoelasticity are established in the context of two commercially available polymer-interlayers. Furthermore, it is shown that the results of small-scale tests agree to a certain degree to the results of the TCB large-scale experiments. In a future step, the results can be used to develop material models for the post breakage performance of laminated glass.

Keywords: glass breakage, laminated glass, relaxation test, viscoelasticity

Procedia PDF Downloads 121