Search results for: Lalit Ahuja
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 30

Search results for: Lalit Ahuja

30 Efficient Utilization of Negative Half Wave of Regulator Rectifier Output to Drive Class D LED Headlamp

Authors: Lalit Ahuja, Nancy Das, Yashas Shetty

Abstract:

LED lighting has been increasingly adopted for vehicles in both domestic and foreign automotive markets. Although this miniaturized technology gives the best light output, low energy consumption, and cost-efficient solutions for driving, the same is the need of the hour. In this paper, we present a methodology for driving the highest class two-wheeler headlamp with regulator and rectifier (RR) output. Unlike usual LED headlamps, which are driven by a battery, regulator, and rectifier (RR) driven, a low-cost and highly efficient LED Driver Module (LDM) is proposed. The positive half of magneto output is regulated and used to charge batteries used for various peripherals. While conventionally, the negative half was used for operating bulb-based exterior lamps. But with advancements in LED-based headlamps, which are driven by a battery, this negative half pulse remained unused in most of the vehicles. Our system uses negative half-wave rectified DC output from RR to provide constant light output at all RPMs of the vehicle. With the negative rectified DC output of RR, we have the advantage of pulsating DC input which periodically goes to zero, thus helping us to generate a constant DC output equivalent to the required LED load, and with a change in RPM, additional active thermal bypass circuit help us to maintain the efficiency and thermal rise. The methodology uses the negative half wave output of the RR along with a linear constant current driver with significantly higher efficiency. Although RR output has varied frequency and duty cycles at different engine RPMs, the driver is designed such that it provides constant current to LEDs with minimal ripple. In LED Headlamps, a DC-DC switching regulator is usually used, which is usually bulky. But with linear regulators, we’re eliminating bulky components and improving the form factor. Hence, this is both cost-efficient and compact. Presently, output ripple-free amplitude drivers with fewer components and less complexity are limited to lower-power LED Lamps. The focus of current high-efficiency research is often on high LED power applications. This paper presents a method of driving LED load at both High Beam and Low Beam using the negative half wave rectified pulsating DC from RR with minimum components, maintaining high efficiency within the thermal limitations. Linear regulators are significantly inefficient, with efficiencies typically about 40% and reaching as low as 14%. This leads to poor thermal performance. Although they don’t require complex and bulky circuitry, powering high-power devices is difficult to realise with the same. But with the input being negative half wave rectified pulsating DC, this efficiency can be improved as this helps us to generate constant DC output equivalent to LED load minimising the voltage drop on the linear regulator. Hence, losses are significantly reduced, and efficiency as high as 75% is achieved. With a change in RPM, DC voltage increases, which can be managed by active thermal bypass circuitry, thus resulting in better thermal performance. Hence, the use of bulky and expensive heat sinks can be avoided. Hence, the methodology to utilize the unused negative pulsating DC output of RR to optimize the utilization of RR output power and provide a cost-efficient solution as compared to costly DC-DC drivers.

Keywords: class D LED headlamp, regulator and rectifier, pulsating DC, low cost and highly efficient, LED driver module

Procedia PDF Downloads 34
29 Cleaner Technology for Stone Crushers

Authors: S. M. Ahuja

Abstract:

There are about 12000 stone crusher units in India and are located in clusters around urban areas to the stone quarries. These crushers create lot of fugitive dust emissions and noise pollution which is a major health hazard for the people working in the crushers and also living in its vicinity. Ambient air monitoring was carried out near various stone crushers and it has been observed that fugitive emission varied from 300 to 8000 mg/Nm3. A number of stone crushers were thoroughly studied and their existing pollution control devices were examined. Limitations in the existing technology were also studied. A technology consisting of minimal effective spray nozzles to reduce the emissions at source followed by a containment cum control system having modular cyclones as air pollution control device has been conceived. Besides preliminary energy audit has also been carried out in some of the stone crushers which indicates substantial potential for energy saving.

Keywords: stone crushers, spray nozzles, energy audit

Procedia PDF Downloads 293
28 Modelling and Simulation of Biomass Pyrolysis

Authors: P. Ahuja, K. S. S. Sai Krishna

Abstract:

There is a concern over the energy shortage in the modern societies as it is one of the primary necessities. Renewable energy, mainly biomass, is found to be one feasible solution as it is inexhaustible and clean energy source all over the world. Out of various methods, thermo chemical conversion is considered to be the most common and convenient method to extract energy from biomass. The thermo-chemical methods that are employed are gasification, liquefaction and combustion. On gasification biomass yields biogas, on liquefaction biomass yields bio-oil and on combustion biomass yields bio-char. Any attempt to biomass gasification, liquefaction or combustion calls for a good understanding of biomass pyrolysis. So, Irrespective of the method used the first step towards the thermo-chemical treatment of biomass is pyrolysis. Pyrolysis mainly converts the solid mass into liquid with gas and residual char as the byproducts. Liquid is used for the production of heat, power and many other chemicals whereas the gas and char can be used as fuels to generate heat.

Keywords: biomass, fluidisation, pyrolysis, simulation

Procedia PDF Downloads 309
27 Formulation Development and Evaluation of Floating Tablets of Venlafaxine Hydrochloride

Authors: Gajera Lalit, Shah Pranav, Shah Shailesh

Abstract:

Venlafaxine hydrochloride has a short elimination half-life of 5 ± 2 hr, and absorption window in the upper part of gastrointestinal tract. The conventional tablets need to be administered two to three times a day and possess an oral bioavailability of 45%. The purpose of this study was to formulate gastroretentive effervescent floating tablets of Venlafaxine HCl. Different grades of HPMC namely K15M, K4M, K100M and E15LV were employed as swelling polymers whereas sodium bicarbonate was employed as gas generating agent. The direct compression method was employed for the formulation of tablets. The tablets were evaluated in terms of hardness, friability, weight variation, drug content, water uptake, in-vitro floating behavior and in-vitro drug release study. All the formulations exhibited very short floating lag time of < 1 min and total floating time of 12 hr. Formulation L3 containing 25 mg and 75 mg of HPMC E15 LV and HPMC K15M respectively exhibited complete drug release within 12 hrs.

Keywords: venlafaxine HCl, hydroxyl propyl methylcellulose, floating gastro retentive tablets, in-vitro drug release, non-fickian diffusion

Procedia PDF Downloads 507
26 Air Pollution Control from Rice Shellers - a Case Study

Authors: S. M. Ahuja

Abstract:

A Rice Sheller is used for obtaining polished white rice from paddy. There are about 3000 Rice Shellers in Punjab and 50000 in India. During the process of shelling lot of dust is emitted from different unit operations like paddy silo, paddy shaker, bucket elevators, huskers, paddy separator etc. These dust emissions have adverse effect on the health of the workers and the wear and tear of the shelling machinery is also fast. All the dust emissions spewing out of these unit operations of a rice Sheller were contained by providing suitable hoods and enclosures while ensuring their workability. These were sucked by providing an induced draft fan followed by a high efficiency cyclone separator that has got an overall dust collection efficiency of more than 90 %. This cyclone separator replaced two cyclone separators and a filter bag house, which the Rice Sheller was already having. The dust concentration in the stack after the installation of cyclone separator is well within the stipulated standards. Besides controlling pollution there is improvement in the quality of products like bran and the life of shelling machinery has also enhanced. The payback period of this technology is less than four shelling months.

Keywords: air pollution, cyclone separator, pneumatic conveying, rice shellers

Procedia PDF Downloads 267
25 Properties of Ground Granulated Blast Furnace Slag Based Geopolymer Concrete

Authors: Niragi Dave, Ruchika Lalit

Abstract:

Concrete is one of the most widely used materials across the globe mostly second to water and generating high carbon dioxide emission during its whole manufacturing due to the presence of cement as an ingredient. Therefore it is necessary to find an alternative material to the Portland cement. This study focused on the use of Ground Granulated Blast Furnace Slag as geopolymer binder. Geopolymer concrete can be an alternative material which is produced by the chemical reaction of inorganic molecules. On the other hand, waste generating from power plants and other industries like iron and steel industries can be effectively used which has disposal problems. Therefore in this study geopolymer concrete is manufactured by 100% replacement of cement content by ground granulated blast furnace slag and a combination of sodium silicate and sodium hydroxide is used as an alkaline solution. The results have shown that the compressive strengths increased with increasing curing time and type of alkali activators. Naphthalene sulfonate-based superplasticizer performed better than other superplasticizers. All the specimens have been cast at ambient temperature.

Keywords: alkali activators, concrete, geopolymer, ground granulated blast furnace slag

Procedia PDF Downloads 291
24 Implementing Building Information Modelling to Attain Lean and Green Benefits

Authors: Ritu Ahuja

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Globally the built environment sector is striving to be highly efficient, quality-centred and socially-responsible. Built environment sector is an integral part of the economy and plays an important role in urbanization, industrialization and improved quality of living. The inherent challenges such as excessive material and process waste, over reliance on resources, energy usage, and carbon footprint need to be addressed in order to meet the needs of the economy. It is envisioned that these challenges can be resolved by integration of Lean-Green-Building Information Modelling (BIM) paradigms. Ipso facto, with BIM as a catalyst, this research identifies the operational and tactical connections of lean and green philosophies by providing a conceptual integration framework and underpinning theories. The research has developed a framework for BIM-based organizational capabilities for enhanced adoption and effective use of BIM within architectural organizations. The study was conducted through a sequential mixed method approach focusing on collecting and analyzing both qualitative and quantitative data. The framework developed as part of this study will enable architectural organizations to successfully embrace BIM on projects and gain lean and green benefits.

Keywords: BIM, lean, green, AEC organizations

Procedia PDF Downloads 159
23 Role of Bariatric Surgery in Polycystic Ovarian Syndrome &Infertility

Authors: Ahuja Ashish, Nain Prabhdeep Singh

Abstract:

Introduction: Polycystic ovarian syndrome(PCOS) is the most common endocrine disorder among women of reproductive age.Pcos encompasses a broad spectrum of signs&symptoms of ovary dysfunction,obesity,blood pressure,insulin resistance & infertility. Bariatric Surgery can be an effective means of weight loss in Pcos & curing infertility. Materials and Methods: 15 female patients were enrolled in the study from 2012-2014.66%(n=10) were in age group of 20-25 years,33%(n=5) were in age group of 25-33 years who underwent. Bariatric surgery in form of Laproscopic sleeve Gastrectomy(LSG)& Roux-en-Y gastric bypass. LSG 73%(n=11), RYGB26% (n=4). Results: There was a significant improvement in obesity (60% excess weight loss)over 1 year after bariatric surgery, in 12 patients there was gross improvement in restoration of menstrual cycle who had irregular menstrual cycle. In 80% patients the serum insulin level showed normal value. Over two years 8 patients become pregnant. Conclusions: 1)Obese women with Pcos maybe able to conceive after Bariatric Surgery. 2) Women with Pcos should only consider bariatric surgery if they were already considering it for other reasons to treat obesity, blood pressure & other co-morbid conditions.

Keywords: obesity, bariatric surgery, polycystic ovarian syndrome, infertility

Procedia PDF Downloads 267
22 Stability Indicating Method Development and Validation for Estimation of Antiasthmatic Drug in Combined Dosages Formed by RP-HPLC

Authors: Laxman H. Surwase, Lalit V. Sonawane, Bhagwat N. Poul

Abstract:

A simple stability indicating high performance liquid chromatographic method has been developed for the simultaneous determination of Levosalbutamol Sulphate and Ipratropium Bromide in bulk and pharmaceutical dosage form using reverse phase Zorbax Eclipse Plus C8 column (250mm×4.6mm), with mobile phase phosphate buffer (0.05M KH2PO4): acetonitrile (55:45v/v) pH 3.5 adjusted with ortho-phosphoric acid, the flow rate was 1.0 mL/min and the detection was carried at 212 nm. The retention times of Levosalbutamol Sulphate and Ipratropium Bromide were 2.2007 and 2.6611 min respectively. The correlation coefficient of Levosalbutamol Sulphate and Ipratropium Bromide was found to be 0.997 and 0.998.Calibration plots were linear over the concentration ranges 10-100µg/mL for both Levosalbutamol Sulphate and Ipratropium Bromide. The LOD and LOQ of Levosalbutamol Sulphate were 2.520µg/mL and 7.638µg/mL while for Ipratropium Bromide was 1.201µg/mL and 3.640 µg/mL. The accuracy of the proposed method was determined by recovery studies and found to be 100.15% for Levosalbutamol Sulphate and 100.19% for Ipratropium Bromide respectively. The method was validated for accuracy, linearity, sensitivity, precision, robustness, system suitability. The proposed method could be utilized for routine analysis of Levosalbutamol Sulphate and Ipratropium Bromide in bulk and pharmaceutical capsule dosage form.

Keywords: levosalbutamol sulphate, ipratropium bromide, RP-HPLC, phosphate buffer, acetonitrile

Procedia PDF Downloads 323
21 Security as Human Value: Issue of Human Rights in Indian Sub-Continental Operations

Authors: Pratyush Vatsala, Sanjay Ahuja

Abstract:

The national security and human rights are related terms as there is nothing like absolute security or absolute human right. If we are committed to security, human right is a problem and also a solution, and if we deliberate on human rights, security is a problem but also part of the solution. Ultimately, we have to maintain a balance between the two co-related terms. As more and more armed forces are being deployed by the government within the nation for maintaining peace and security, using force against its own citizen, the search for a judicious balance between intent and action needs to be emphasized. Notwithstanding that a nation state needs complete political independence; the search for security is a driving force behind unquestioned sovereignty. If security is a human value, it overlaps the value of freedom, order, and solidarity. Now, the question needs to be explored, to what extent human rights can be compromised in the name of security in Kashmir or Mizoram like places. The present study aims to explore the issue of maintaining a balance between the use of power and good governance as human rights, providing security as a human value. This paper has been prepared with an aim of strengthening the understanding of the complex and multifaceted relationship between human rights and security forces operating for conflict management and identifies some of the critical human rights issues raised in the context of security forces operations highlighting the relevant human rights principles and standards in which Security as human value be respected at all times and in particular in the context of security forces operations in India.

Keywords: Kashmir, Mizoram, security, value, human right

Procedia PDF Downloads 244
20 Urban Resilince and Its Prioritised Components: Analysis of Industrial Township Greater Noida

Authors: N. Mehrotra, V. Ahuja, N. Sridharan

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Resilience is an all hazard and a proactive approach, require a multidisciplinary input in the inter related variables of the city system. This research based to identify and operationalize indicators for assessment in domain of institutions, infrastructure and knowledge, all three operating in task oriented community networks. This paper gives a brief account of the methodology developed for assessment of Urban Resilience and its prioritized components for a target population within a newly planned urban complex integrating Surajpur and Kasna village as nodes. People’s perception of Urban Resilience has been examined by conducting questionnaire survey among the target population of Greater Noida. As defined by experts, Urban Resilience of a place is considered to be both a product and process of operation to regain normalcy after an event of disturbance of certain level. Based on this methodology, six indicators are identified that contribute to perception of urban resilience both as in the process of evolution and as an outcome. The relative significance of 6 R’ has also been identified. The dependency factor of various resilience indicators have been explored in this paper, which helps in generating new perspective for future research in disaster management. Based on the stated factors this methodology can be applied to assess urban resilience requirements of a well planned town, which is not an end in itself, but calls for new beginnings.

Keywords: disaster, resilience, system, urban

Procedia PDF Downloads 427
19 Climate Change Impacts on Future Wheat Growing Areas

Authors: Rasha Aljaryian, Lalit Kumar

Abstract:

Climate is undergoing continuous change and this trend will affect the cultivation areas ofmost crops, including wheat (Triticum aestivum L.), in the future. The current suitable cultivation areas may become unsuitable climatically. Countries that depend on wheat cultivation and export may suffer an economic loss because of production decline. On the other hand, some regions of the world could gain economically by increasing cultivation areas. This study models the potential future climatic suitability of wheat by using CLIMEX software. Two different global climate models (GCMs) were used, CSIRO-Mk3.0 (CS) and MIROC-H (MR), with two emission scenarios (A2, A1B). The results of this research indicate that the suitable climatic areas for wheat in the southern hemisphere, such as Australia, are expected to contract by the end of this century. However, some unsuitable or marginal areas will become climatically suitable under future climate scenarios. In North America and Europe further expansion inland could occur. Also, the results illustrate that heat and dry stresses as abiotic climatic factors will play an important role in wheat distribution in the future. Providing sufficient information about future wheat distribution will be useful for agricultural ministries and organizations to manage the shift in production areas in the future. They can minimize the expected harmful economic consequences by preparing strategic plans and identifying new areas for wheat cultivation.

Keywords: Climate change, Climate modelling, CLIMEX, Triticum aestivum, Wheat

Procedia PDF Downloads 214
18 Triple Modulation on Wound Healing in Glaucoma Surgery Using Mitomycin C and Ologen Augmented with Anti-Vascular Endothelial Growth Factor

Authors: Reetika Sharma, Lalit Tejwani, Himanshu Shekhar, Arun Singhvi

Abstract:

Purpose: To describe a novel technique of trabeculectomy targeting triple modulation on wound healing to increase the overall success rate. Method: Ten eyes of 10 patients underwent trabeculectomy with subconjunctival mitomycin C (0.4mg/ml for 4 minutes) application combined with Ologen implantation subconjunctivally and subsclerally. Five of these patients underwent additional phacoemulsification with intraocular lens implantation. The Ologen implant was wet with 0.1 ml Bevacizumab. Result: All the eyes achieved target intraocular pressure (IOP), which was maintained until one year of follow-up. Two patients needed anterior chamber reformation at day two post surgery. One patient needed cataract surgery after four months of surgery and achieved target intraocular pressure on two topical antiglaucoma medicines. Conclusion: Vascular endothelial growth factor (VEGF) concentration has been seen to increase in the aqueous humor after filtration surgery. Ologen implantation helps in collagen remodelling, antifibroblastic response, and acts as a spacer. Bevacizumab augmented Ologen, in addition, targets the increased VEGF and helps in decreasing scarring. Anti-VEGF augmented Ologen in trabeculectomy with mitomycin C (MMC) hence appears to have encouraging short-term intraocular pressure control.

Keywords: ologen, anti-VEGF, trabeculectomy, scarring

Procedia PDF Downloads 158
17 The Role of Volunteers in Quality Palliative Care Delivery

Authors: Aditya Manna, Lalit Kumar Khanra, Shyamal Kumar Sarkar

Abstract:

Introduction: Here in India almost 75% of cancer patient die a sad death of neglect due to lack of awareness about palliative care and low economic level. Surveys in India show that two third of cancer patient do not get proper care during the terminal phase of their life. Palliative care through volunteers can make a significant difference in this respect. Objective: To identify and try to solve, to the extent possible, the main difficulties in giving palliative care to the terminal cancer patients of the area. And evaluate the impact of volunteer’s direct care of palliative patients and their families. Methods: Feedback from patients and their relatives regarding the palliative care they receive from nursing home and from volunteers and compare the two. Also feedback from volunteers regarding their positive and negative experience while delivering palliative care service. Then evaluate the data to compare and improve the quality of service. Results: We carried out two studies. One study was undertaken in nursing home palliative care and another was in home setting by volunteers. Both studies were in adult palliative care services. Since January 2015, 496 cases were studied to enquire about their experience in both home based care and nursing home care. Both the studies fulfilled our quality appraisal criteria. One found that those families and patients who received home visits from volunteers were significantly more satisfied. The study highlighted the value of the role of volunteers in better satisfaction of patients and their families. Conclusions: Further research is needed to evaluate the role of volunteers in palliative care and how it can be delivered appropriately and effectively. We also wish to compare our findings with similar studies elsewhere.

Keywords: palliative care, terminal care, cancer, home care

Procedia PDF Downloads 597
16 Cheiloscopy: A Study on Predominant Lip Print Patterns among the Gujarati Population

Authors: Pooja Ahuja, Tejal Bhutani, M. S. Dahiya

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Cheiloscopy, the study of lip prints, is a tool in forensic investigation technique that deals with identification of individuals based on lips patterns. The objective of this study is to determine predominant lip print pattern found among the Gujarati population, to evaluate whether any sex difference exists and to study the permanence of the pattern over six months duration. The study comprised of 100 healthy individuals (50 males and 50 females), in the age group of 18 to 25 years of Gujarati population of the Gandhinagar region of the Gujarat state, India. By using Suzuki and Tsuchihashi classification, Lip prints were then divided into four quadrants and also classified on the basis of peripheral shape of the lips. Materials used to record the lip prints were dark brown colored lipstick, cellophane tape, and white bond paper. Lipstick was applied uniformly, and lip prints were taken on the glued portion of cellophane tape and then stuck on to a white bond paper. These lip prints were analyzed with magnifying lens and virtually with stereo microscope. On the analysis of the subject population, results showed Branched pattern Type II (29.57 percentage) to be most predominant in the Gujarati population. Branched pattern Type II (35.60 percentage) and long vertical Type I (28.28 percentage) were most prevalent in males and females respectively and large full lips were most predominantly present in both the sexes. The study concludes that lip prints in any form can be an effective tool for identification of an individual in a closed or open group forms.

Keywords: cheiloscopy, lip pattern, predomianant, Gujarati population

Procedia PDF Downloads 272
15 Renoprotective Effect of Alcoholic Extract of Bacopa monnieri via Inhibition of Advanced Glycation End Products and Oxidative Stress in Stz-Nicotinamide Induced Diabetic Nephropathy

Authors: Lalit Kishore, Randhir Singh

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Diabetic nephropathy (DN) is the major cause of morbidity among diabetic patients. In this study, the effect of Bacopa monnieri Linn. (Brahmi, BM), was studied in a Streptozotocin (STZ)-induced experimental rat model of DN. Diabetic nephropathy was induced in Male Wistar rats (body weight- 300± 10 gms) by single intra-peritoneal injection of STZ (45mg/kg, i.p.) after 15 min of Nicotinamide (230 mg/kg) administration. Different doses of alcoholic extract i.e. 100, 200 and 400 mg/kg was given for 45 days by oral gavage after induction of DN. Blood glucose level, serum insulin, glycosylated haemoglobin, renal parameters (serum urea, uric acid, creatinine and BUN) and lipid profile (total cholesterol, triglycerides, HDL, LDL and VLDL levels) were measured. Concentration of thiobarbituric acid reactive species (TBARS) and levels of antioxidant enzymes of reduced glutathione (GSH), superoxide dismutase (SOD), and catalase (CAT) were evaluated in the kidney, liver and pancreas. At the end of treatment period the alcoholic extract of BM reduced the elevated level of blood glucose, serum insulin, renal parameters, lipid levels, TBARS, AGE’s in kidney and significantly increased body weight, HDL and antioxidant enzymes in dose dependent manner as compared to diabetic control animals. These results suggested the BM possesses significant renoprotective activity.

Keywords: AGE's, lipid profile, oxidative stress, renal parameters

Procedia PDF Downloads 285
14 Climate Change in Awash River Basin of Ethiopia: A Projection Study Using Global and Regional Climate Model Simulations

Authors: Mahtsente Tadese, Lalit Kumar, Richard Koech

Abstract:

The aim of this study was to project and analyze climate change in the Awash River Basin (ARB) using bias-corrected Global and Regional Climate Model simulations. The analysis included a baseline period from 1986-2005 and two future scenarios (the 2050s and 2070s) under two representative concentration pathways (RCP4.5 and RCP8.5). Bias correction methods were evaluated using graphical and statistical methods. Following the evaluation of bias correction methods, the Distribution Mapping (DM) and Power Transformation (PT) were used for temperature and precipitation projection, respectively. The 2050s and 2070s RCP4 simulations showed an increase in precipitation during half of the months with 32 and 10%, respectively. Moreover, the 2050s and 2070s RCP8.5 simulation indicated a decrease in precipitation with 18 and 26%, respectively. The 2050s and 2070s RCP8.5 simulation indicated a significant decrease in precipitation in four of the months (February/March to May) with the highest decreasing rate of 34.7%. The 2050s and 2070s RCP4.5 simulation showed an increase of 0.48-2.6 °C in maximum temperature. In the case of RCP8.5, the increase rate reached 3.4 °C and 4.1 °C in the 2050s and 2070s, respectively. The changes in precipitation and temperature might worsen the water stress, flood, and drought in ARB. Moreover, the critical focus should be given to mitigation strategies and management options to reduce the negative impact. The findings of this study provide valuable information on future precipitation and temperature change in ARB, which will help in the planning and design of sustainable mitigation approaches in the basin.

Keywords: variability, climate change, Awash River Basin, precipitation

Procedia PDF Downloads 146
13 Design and Radio Frequency Characterization of Radial Reentrant Narrow Gap Cavity for the Inductive Output Tube

Authors: Meenu Kaushik, Ayon K. Bandhoyadhayay, Lalit M. Joshi

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Inductive output tubes (IOTs) are widely used as microwave power amplifiers for broadcast and scientific applications. It is capable of amplifying radio frequency (RF) power with very good efficiency. Its compactness, reliability, high efficiency, high linearity and low operating cost make this device suitable for various applications. The device consists of an integrated structure of electron gun and RF cavity, collector and focusing structure. The working principle of IOT is a combination of triode and klystron. The cathode lies in the electron gun produces a stream of electrons. A control grid is placed in close proximity to the cathode. Basically, the input part of IOT is the integrated structure of gridded electron gun which acts as an input cavity thereby providing the interaction gap where the input RF signal is applied to make it interact with the produced electron beam for supporting the amplification phenomena. The paper presents the design, fabrication and testing of a radial re-entrant cavity for implementing in the input structure of IOT at 350 MHz operating frequency. The model’s suitability has been discussed and a generalized mathematical relation has been introduced for getting the proper transverse magnetic (TM) resonating mode in the radial narrow gap RF cavities. The structural modeling has been carried out in CST and SUPERFISH codes. The cavity is fabricated with the Aluminum material and the RF characterization is done using vector network analyzer (VNA) and the results are presented for the resonant frequency peaks obtained in VNA.

Keywords: inductive output tubes, IOT, radial cavity, coaxial cavity, particle accelerators

Procedia PDF Downloads 86
12 Efficacy of Comprehensive Diabetic Care Program with the Reduction of HbA1c in Overweight Type II Diabetes Mellitus Patients: A Retrospective Study

Authors: Rohit Sane, Pravin Ghadigaonkar, Purvi Ahuja, Suvarna Tirmare, Archana Kelhe, Kranti Shinde, Rahul Mandole

Abstract:

To evaluate the efficacy of Comprehensive Diabetic Care Program with the reduction of HbA1c in overweight Diabetes Mellitus Type II patients retrospectively. Methods: Retrospective study was carried out on 34 overweight type II diabetic patients (Mean Age = 54.58 ±11.38 yrs). A total of 34 patients were enrolled after screening of 68 patients (HbA1c 7-10%). The patients were on concomitant drugs namely insulin (11.76%), DPP-4 inhibitor (17.64%), Biguanide (55.88%), Sulfonylurea (52.94%), thiazolidinedione (11.76%), other medications (20.58%) and no allopathic medications (14.70%). The patients were given Comprehensive Diabetic Care Program consisting of panchkarma procedures namely snehana (external oleation), swedana (passive heat therapy) and basti (enema), which was completed in 15 sittings. During the therapy and next 90 days, the patients followed low carbohydrate and moderate protein & fat diet. The primary endpoint of this study was the evaluation of reduction in HbA1c at the end of the follow-up after 90 days. Results: Thirty-four overweight type II diabetic patients (mean age: 54.58[±11.38], HbA1c[7-10%], 67.64% male and 32.35% female) were enrolled in the study. A significant reduction was observed in HbA1c levels (14.30%, p<0.05) at the end of the 90 days follow-up as compared to baseline. Also, BMI was reduced by 5.87%. There was reduction in the usage of the concomitant drugs namely insulin (2.94%), DPP-4 inhibitor (2.94%), Biguanide (32.35%), Sulfonylurea (35.29%), thiazolidinedione (5.88%), other medications(17.64%) and no allopathic medications (32.35%). Conclusion: The results of the study highlight not only in the reduction of HbA1c, but also in BMI and drug tapering of the CDC program in the overweight type II diabetic patients with HbA1c (7-10%).

Keywords: HbA1c, low carb diet, Panchakarma therapy, Type II Diabetes

Procedia PDF Downloads 251
11 Risk Factors for Postoperative Recurrence in Indian Patients with Crohn’s Disease

Authors: Choppala Pratheek, Vineet Ahuja

Abstract:

Background: Crohn's disease (CD) recurrence following surgery is a common challenge, and current detection methods rely on risk factors identified in Western populations. This study aimed to investigate the risk factors and rates of postoperative CD recurrence in a tuberculosis-endemic region like India. Retrospective data was collected from a structured database from a specialty IBD clinic by reviewing case files from January 2005 to December 2021. Inclusion criteria involved CD patients diagnosed based on the ECCO-ESGAR consensus guidelines, who had undergone at least one intestinal resection and had a minimum follow-up period of one year at the IBD clinic. Results: A total of 90 patients were followed up for a median period of 45 months (IQR, 20.75 - 72.00). Out of the 90 patients, 61 received ATT prior to surgery, with a mean delay in diagnosis of 2.5 years, although statistically non-significant (P=0.078). Clinical recurrence occurred in 50% of patients, with the cumulative rate increasing from 13.3% at one year to 40% at three years. Among 63 patients who underwent endoscopy, 65.7% showed evidence of endoscopic recurrence, with the cumulative rate increasing from 31.7% at one year to 55.5% at four years. Smoking was identified as a significant risk factor for early endoscopic recurrence (P=0.001) by Cox regression analysis, but no other risk factors were identified. Initiating post-operative medications prior to clinical recurrence delayed its onset (P=0.004). Subgroup analysis indicated that endoscopic monitoring aided in the early identification of recurrence (P=0.001). The findings contribute to enhancing post-operative CD management strategies in such regions where the disease burden is escalating.

Keywords: crohns, post operative, tuberculosis-endemic, risk factors

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10 Efficacy of Collagen Matrix Implants in Phacotrabeculectomy with Mitomycin C at One Year

Authors: Lalit Tejwani, Reetika Sharma, Arun Singhvi, Himanshu Shekhar

Abstract:

Purpose: To assess the efficacy of collagen matrix implant (Ologen) in phacotrabeculectomy augmented with mitomycin C (MMC). Methods: A biodegradable collagen matrix (Ologen) was placed in the subconjunctival and subscleral space in twenty-two eyes of 22 patients with glaucoma and cataract who underwent combined phacoemulsification and trabeculectomy augmented with MMC. All of them were examined preoperatively and on the first postoperative day. They were followed for twelve months after surgery. Any intervention needed in follow-up period was noted. Any complication was recorded. The primary outcome measure was postoperative intraocular pressure at one year follow-up. Any additional postoperative treatments needed and adverse events were noted. Results: The mean age of patients included in the study was 57.77 ± 9.68 years (range=36 to 70 years). All the patients were followed for at least one year. Three patients had history of failed trabeculectomy. Fifteen patients had chronic angle closure glaucoma with cataract, five had primary open angle glaucoma with cataract, one had uveitic glaucoma with cataract, and one had juvenile open angle glaucoma with cataract. Mean preoperative IOP was 32.63 ± 8.29 mm Hg, eighteen patients were on oral antiglaucoma medicines. The mean postoperative IOP was 10.09 ± 2.65 mm Hg at three months, 10.36 ± 2.19 mm Hg at six months and 11.36 ± 2.72 mm Hg at one year follow up. No adverse effect related to Ologen was seen. Anterior chamber reformation was done in five patients, and three needed needling of bleb. Four patients needed additional antiglaucoma medications in the follow-up period. Conclusions: Combined phacotrabeculectomy with MMC with Ologen implantation appears to be a safe and effective option in glaucoma patients needing trabeculectomy with significant cataract. Comparative studies with longer duration of follow-up in larger number of patients are needed.

Keywords: combined surgery, ologen, phacotrabeculectomy, success

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9 Role of Ologen in Previously Failed Trabeculectomy in Advanced Glaucoma

Authors: Reetika Sharma, Lalit Tejwani, Himanshu Shekhar, Arun Singhvi

Abstract:

Purpose: Advanced Glaucoma with Failed trab is not an uncommon sight in glaucoma clinic, and such cases usually tend to present with high intraocular pressure (IOP) and advanced cupping, or even glaucomatous atrophy stage. Re-surgery is needed for such cases, and wound modulation poses a major challenge in these cases. We share our experience in this case series with the use of Ologen (collagen matrix implant) along with MMC 0.04% used in surgery. The purpose of the study was to evaluate the efficacy and outcome of collagen matrix implant in re-trabeculectomy in advanced glaucoma cases. Methodology: Eleven eyes of 11 patients (one eye of one patient) underwent re-trabeculectomy surgery with MMC and Ologen. Ologen implant was used in sub scleral and subconjunctival space, as a spacer and wound modulator. In five cases, triple modulation with implant soaked in anti-VEGF was used. Results: All patients had cupping more than 0.9, and one case was GOA. All cases were on maximal medication at presentation and majority were on systemic anti-glaucoma therapy also. Post-surgery, follow-up ranged from 13 – 34 months, and all cases had a follow longer than the gap between previous surgery (which was failed) and re-trab. One case needed AC reformation and one needling was done. Phaco was done at same sitting in four cases. All cases had their IOP lowered post surgery, and vision was maintained in all, however one case was considered as failed re-surgery case. Topical medication was needed in seven cases post-surgery also. Conclusion: Ologen as adjuvant should be considered in all re-trab cases and all high risk and advanced cases, and triple modulation can be next step in these cases. Aggressive IOP control and non- reluctance to continue topical medications post second surgery should be considered in such cases, to give them best possible vision.

Keywords: failed trabeculectomy, ologen, trabeculectomy, advanced glaucoma

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8 Development and Evaluation of a Nutraceutical Herbal Summer Drink

Authors: Munish Garg, Vinni Ahuja

Abstract:

In the past few years, the high consumption of soft drinks has attracted negative attention world-wide due to its possible adverse effects, leading the health conscious people to find alternative nutraceutical or herbal health drinks. In the present study, a nutraceutical soft drink was developed utilizing some easily available and well known traditional herbs having nutritional potential. The key ingredients were selected as bael, amla, lemon juice, ashwagandha and poppy seeds based on their household routine use in the summer with proven refreshing, cooling and energetic feeling since ages. After several trials made, the final composition of nutraceutical summer soft drink was selected as most suitable combination based on the taste, physicochemical, microbial and organoleptic point of view. The physicochemical analysis of the prepared drink found to contain optimum level of titratable acidity, total soluble solids and pH which were in accordance of the commercial recommendations. There were no bacterial colonies found in the product therefore found within limits. During the nine point’s hedonic scale sensory evaluation, the drink was strongly liked for colour, taste, flavour and texture. The formulation was found to contain flavonoids (80mg/100ml), phenolics (103mg/100ml), vitamin C (250mg/100ml) and has antioxidant potential (75.52%) apart from providing several other essential vitamins, minerals and healthy components. The developed nutraceutical drink provides an economical and feasible option for the consumers with very good taste combined with potential health benefits. The present drink is potentially capable to replace the synthetic soft drinks available in the market.

Keywords: herbal drink, summer drink, nutraceuticals, soft drink

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7 Evaluation of the Use of Proseal LMA in Patients Undergoing Elective Lower Segment Caesarean Section under General Anaesthesia: A Prospective Randomised Controlled Study

Authors: Shalini Saini, Sharmila Ahuja

Abstract:

Anaesthesia for caesarean section poses challenges unique to the obstetric patient due to changes in the airway and respiratory system. The choice of anaesthesia for caesarean section depends on various factors however general anaesthesia (GA) is necessary for certain situations. Supraglottic airway devices are an emerging method to secure airway, especially in difficult situations. Of these devices, proseal –LMA (PLMA) is designed to provide better protection of the airway. The use of PLMA has been reported successfully as a rescue device in difficult intubation situations and in patients undergoing elective caesarean section without any complications. The study was prospective and randomised and was designed to compare PLMA in patients undergoing elective lower segment caesarean section (LSCS) with the endotracheal tube (ETT). Patients undergoing LSCS under GA belonging to ASA grade 1 and 2 were included. Patients with the history of fewer than 6 hrs of fasting, known/predicted difficult airway, obesity, gastroesophageal reflux disease, hypertensive disorder were excluded. A standard anaesthesia protocol was followed. All patients received aspiration prophylaxis. The airway was secured with either PLMA or ETT. Parameters noted were- ease of insertion, adequacy of ventilation, hemodynamic changes at insertion and removal of device, incidence of regurgitation and aspiration. Data was analysed by unpaired t- test, Chi-square /Fisher’s test. The findings of our study indicated that PLMA was easy to insert (20.67±6.835 sec) with comparable insertion time to TT (18.33 ± 4.971, p 0.136) and adequate ventilation was achieved with very minimal hemodynamic changes seen with PLMA as compared to ETT at insertion and removal of devices (p 0.01). There was no incidence of regurgitation with the use of PLMA. The incidence of a postoperative sore throat was minimal (6.7%) with PLMA (p<0.05). PLMA appears to be a safe alternative to ETT for selected obstetric patients undergoing elective LSCS. Further study with a larger group of patients is required to establish the safety of PLMA in obstetric patients.

Keywords: caesarean section, general anaesthesia, proseal LMA, endotracheal tube

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6 Formula Student Car: Design, Analysis and Lap Time Simulation

Authors: Rachit Ahuja, Ayush Chugh

Abstract:

Aerodynamic forces and moments, as well as tire-road forces largely affects the maneuverability of the vehicle. Car manufacturers are largely fascinated and influenced by various aerodynamic improvements made in formula cars. There is constant effort of applying these aerodynamic improvements in road vehicles. In motor racing, the key differentiating factor in a high performance car is its ability to maintain highest possible acceleration in appropriate direction. One of the main areas of concern in motor racing is balance of aerodynamic forces and stream line the flow of air across the body of the vehicle. At present, formula racing cars are regulated by stringent FIA norms, there are constrains for dimensions of the vehicle, engine capacity etc. So one of the fields in which there is a large scope of improvement is aerodynamics of the vehicle. In this project work, an attempt has been made to design a formula- student (FS) car, improve its aerodynamic characteristics through steady state CFD simulations and simultaneously calculate its lap time. Initially, a CAD model of a formula student car is made using SOLIDWORKS as per the given dimensions and a steady-state external air-flow simulation is performed on the baseline model of the formula student car without any add on device to evaluate and analyze the air-flow pattern around the car and aerodynamic forces using FLUENT Solver. A detailed survey on different add-on devices used in racing application like: - front wing, diffuser, shark pin, T- wing etc. is made and geometric model of these add-on devices are created. These add-on devices are assembled with the baseline model. Steady state CFD simulations are done on the modified car to evaluate the aerodynamic effects of these add-on devices on the car. Later comparison of lap time simulation of the formula student car with and without the add-on devices is done with the help of MATLAB. Aerodynamic performances like: - lift, drag and their coefficients are evaluated for different configuration and design of the add-on devices at different speed of the vehicle. From parametric CFD simulations on formula student car attached with add-on devices, there is a considerable amount of drag and lift force reduction besides streamlining the airflow across the car. The best possible configuration of these add-on devices is obtained from these CFD simulations and also use of these add-on devices have shown an improvement in performance of the car which can be compared by various lap time simulations of the car.

Keywords: aerodynamic performance, front wing, laptime simulation, t-wing

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5 Depolymerised Natural Polysaccharides Enhance the Production of Medicinal and Aromatic Plants and Their Active Constituents

Authors: M. Masroor Akhtar Khan, Moin Uddin, Lalit Varshney

Abstract:

Recently, there has been a rapidly expanding interest in finding applications of natural polymers in view of value addition to agriculture. It is now being realized that radiation processing of natural polysaccharides can be beneficially utilized either to improve the existing methodologies used for processing the natural polymers or to impart value addition to agriculture by converting them into more useful form. Gamma-ray irradiation is employed to degrade and lower the molecular weight of some of the natural polysaccharides like alginates, chitosan and carrageenan into small sized oligomers. When these oligomers are applied to plants as foliar sprays, they elicit various kinds of biological and physiological activities, including promotion of plant growth, seed germination, shoot elongation, root growth, flower production, suppression of heavy metal stress, etc. Furthermore, application of these oligomers can shorten the harvesting period of various crops and help in reducing the use of insecticides and chemical fertilizers. In recent years, the oligomers of sodium alginate obtained by irradiating the latter with gamma-rays at 520 kGy dose are being employed. It was noticed that the oligomers derived from the natural polysaccharides could induce growth, photosynthetic efficiency, enzyme activities and most importantly the production of secondary metabolite in the plants like Artemisia annua, Beta vulgaris, Catharanthus roseus, Chrysopogon zizanioides, Cymbopogon flexuosus, Eucalyptus citriodora, Foeniculum vulgare, Geranium sp., Mentha arvensis, Mentha citrata, Mentha piperita, Mentha virdis, Papaver somniferum and Trigonella foenum-graecum. As a result of the application of these oligomers, the yield and/or contents of the active constituents of the aforesaid plants were significantly enhanced. The productivity, as well as quality of medicinal and aromatic plants, may be ameliorated by this novel technique in an economical way as a very little quantity of these irradiated (depolymerised) polysaccharides is needed. Further, this is a very safe technique, as we did not expose the plants directly to radiation. The radiation was used to depolymerize the polysaccharides into oligomers.

Keywords: essential oil, medicinal and aromatic plants, plant production, radiation processed polysaccharides, active constituents

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4 Study of Unsteady Behaviour of Dynamic Shock Systems in Supersonic Engine Intakes

Authors: Siddharth Ahuja, T. M. Muruganandam

Abstract:

An analytical investigation is performed to study the unsteady response of a one-dimensional, non-linear dynamic shock system to external downstream pressure perturbations in a supersonic flow in a varying area duct. For a given pressure ratio across a wind tunnel, the normal shock's location can be computed as per one-dimensional steady gas dynamics. Similarly, for some other pressure ratio, the location of the normal shock will change accordingly, again computed using one-dimensional gas dynamics. This investigation focuses on the small-time interval between the first steady shock location and the new steady shock location (corresponding to different pressure ratios). In essence, this study aims to shed light on the motion of the shock from one steady location to another steady location. Further, this study aims to create the foundation of the Unsteady Gas Dynamics field enabling further insight in future research work. According to the new pressure ratio, a pressure pulse, generated at the exit of the tunnel which travels and perturbs the shock from its original position, setting it into motion. During such activity, other numerous physical phenomena also happen at the same time. However, three broad phenomena have been focused on, in this study - Traversal of a Wave, Fluid Element Interactions and Wave Interactions. The above mentioned three phenomena create, alter and kill numerous waves for different conditions. The waves which are created by the above-mentioned phenomena eventually interact with the shock and set it into motion. Numerous such interactions with the shock will slowly make it settle into its final position owing to the new pressure ratio across the duct, as estimated by one-dimensional gas dynamics. This analysis will be extremely helpful in the prediction of inlet 'unstart' of the flow in a supersonic engine intake and its prominence with the incoming flow Mach number, incoming flow pressure and the external perturbation pressure is also studied to help design more efficient supersonic intakes for engines like ramjets and scramjets.

Keywords: analytical investigation, compression and expansion waves, fluid element interactions, shock trajectory, supersonic flow, unsteady gas dynamics, varying area duct, wave interactions

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3 Irradiated-Chitosan and Methyl Jasmonate Modulate the Growth, Physiology and Alkaloids Production in Catharanthus roseus (l.) G. Don.

Authors: Moin Uddin, M. Masroor A. Khan, Faisal Rasheed, Tariq Ahmad Dar, Akbar Ali, Lalit Varshney

Abstract:

Oligomers, obtained by exposing the natural polysaccharides (alginate, carrageenan, chitosan, etc.) to cobalt-60 generated gamma radiation may prove as potent plant growth promoters when applied as foliar sprays to the plants. They function as endogenous growth elicitors, triggering the synthesis of different enzymes and modulating various plant responses by exploiting the gene expression. Exogenous application of Jasmonic acid or of its methyl ester, methyl jasmonate (MeJ) has been reported to increase the secondary metabolites production in medicinal and aromatic plants. Keeping this in mind, three pot experiments were conducted to test whether the foliar application of irradiated-chitosan (IC) and MeJ, applied alone or in combination, could augment the active constituents as well as growth, physiological and yield attributes of Catharanthus roseus, which carries anticancer alkaloids, viz. vincristine and vinblastine, in its leaves in addition to various other useful alkaloids. Totally, 5 spray treatments, comprising various aqueous solutions of IC [20, 40, 80 and 160 mg L-1 (Experiment 1)], MeJ (10, 20, 30 and 40 mg L-1 (Experiment 2)] and those of IC+MeJ [40+20, 40+30, 80+20, 80+30, 160+20 and 160+30 mg L-1 (Experiment 3)], were applied at seven days interval. Total leaf-alkaloids content as well as growth, physiological and yield parameters, evaluated at 120 days after sowing, were significantly enhanced by IC application. IC application could not increase the leaf-content of vincristine and vinblastine; nonetheless, it significantly augmented the yield of these alkaloids owing to enhancing the dry mass of leaves per plant. MeJ application, particularly at 30 mg L-1, increased both content (17%) and yield (48%) of total leaf-alkaloids as well as the content and yield of vincristine ( 29 and 63%, respectively) and vinblastine (14 and 44%, respectively) alkaloids, though it significantly decreased most other parameters studied, particularly at higher concentrations (30 and 40 mg L-1 of MeJ). As compared to the control (water-spray treatment), collective application of IC (80 mg L-1) and MeJ (20 mg L-1) resulted in the highest values of most of the parameters studied. However, 80 mg L-1 of IC applied with 30 mg L-1 of MeJ gave the best results for the content and yield of total as well as anticancer leaf-alkaloids (vincristine and vinblastine). Comparing the control, it increased the content and yield of total leaf-alkaloids (37 and 118%, respectively) and those of vincristine (65 and 163%, respectively) and vinblastine (31 and 107%, respectively). Conclusively, the applied technique significantly enhanced the production of total as well as anticancer alkaloids of Catharanthus roseus.

Keywords: anticancer alkaloids (vincristine and vinblastine), catharanthus roseus, irradiated chitosan, methyl jasmonate

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2 Infestation in Omani Date Palm Orchards by Dubas Bug Is Related to Tree Density

Authors: Lalit Kumar, Rashid Al Shidi

Abstract:

Phoenix dactylifera (date palm) is a major crop in many middle-eastern countries, including Oman. The Dubas bug Ommatissus lybicus is the main pest that affects date palm crops. However not all plantations are infested. It is still uncertain why some plantations get infested while others are not. This research investigated whether tree density and the system of planting (random versus systematic) had any relationship with infestation and levels of infestation. Remote Sensing and Geographic Information Systems were used to determine the density of trees (number of trees per unit area) while infestation levels were determined by manual counting of insects on 40 leaflets from two fronds on each tree, with a total of 20-60 trees in each village. The infestation was recorded as the average number of insects per leaflet. For tree density estimation, WorldView-3 scenes, with eight bands and 2m spatial resolution, were used. The Local maxima method, which depends on locating of the pixel of highest brightness inside a certain exploration window, was used to identify the trees in the image and delineating individual trees. This information was then used to determine whether the plantation was random or systematic. The ordinary least square regression (OLS) was used to test the global correlation between tree density and infestation level and the Geographic Weight Regression (GWR) was used to find the local spatial relationship. The accuracy of detecting trees varied from 83–99% in agricultural lands with systematic planting patterns to 50–70% in natural forest areas. Results revealed that the density of the trees in most of the villages was higher than the recommended planting number (120–125 trees/hectare). For infestation correlations, the GWR model showed a good positive significant relationship between infestation and tree density in the spring season with R² = 0.60 and medium positive significant relationship in the autumn season, with R² = 0.30. In contrast, the OLS model results showed a weaker positive significant relationship in the spring season with R² = 0.02, p < 0.05 and insignificant relationship in the autumn season with R² = 0.01, p > 0.05. The results showed a positive correlation between infestation and tree density, which suggests the infestation severity increased as the density of date palm trees increased. The correlation result showed that the density alone was responsible for about 60% of the increase in the infestation. This information can be used by the relevant authorities to better control infestations as well as to manage their pesticide spraying programs.

Keywords: dubas bug, date palm, tree density, infestation levels

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1 Design Flood Estimation in Satluj Basin-Challenges for Sunni Dam Hydro Electric Project, Himachal Pradesh-India

Authors: Navneet Kalia, Lalit Mohan Verma, Vinay Guleria

Abstract:

Introduction: Design Flood studies are essential for effective planning and functioning of water resource projects. Design flood estimation for Sunni Dam Hydro Electric Project located in State of Himachal Pradesh, India, on the river Satluj, was a big challenge in view of the river flowing in the Himalayan region from Tibet to India, having a large catchment area of varying topography, climate, and vegetation. No Discharge data was available for the part of the river in Tibet, whereas, for India, it was available only at Khab, Rampur, and Luhri. The estimation of Design Flood using standard methods was not possible. This challenge was met using two different approaches for upper (snow-fed) and lower (rainfed) catchment using Flood Frequency Approach and Hydro-metrological approach. i) For catchment up to Khab Gauging site (Sub-Catchment, C1), Flood Frequency approach was used. Around 90% of the catchment area (46300 sqkm) up to Khab is snow-fed which lies above 4200m. In view of the predominant area being snow-fed area, 1 in 10000 years return period flood estimated using Flood Frequency analysis at Khab was considered as Probable Maximum Flood (PMF). The flood peaks were taken from daily observed discharges at Khab, which were increased by 10% to make them instantaneous. Design Flood of 4184 cumec thus obtained was considered as PMF at Khab. ii) For catchment between Khab and Sunni Dam (Sub-Catchment, C2), Hydro-metrological approach was used. This method is based upon the catchment response to the rainfall pattern observed (Probable Maximum Precipitation - PMP) in a particular catchment area. The design flood computation mainly involves the estimation of a design storm hyetograph and derivation of the catchment response function. A unit hydrograph is assumed to represent the response of the entire catchment area to a unit rainfall. The main advantage of the hydro-metrological approach is that it gives a complete flood hydrograph which allows us to make a realistic determination of its moderation effect while passing through a reservoir or a river reach. These studies were carried out to derive PMF for the catchment area between Khab and Sunni Dam site using a 1-day and 2-day PMP values of 232 and 416 cm respectively. The PMF so obtained was 12920.60 cumec. Final Result: As the Catchment area up to Sunni Dam has been divided into 2 sub-catchments, the Flood Hydrograph for the Catchment C1 has been routed through the connecting channel reach (River Satluj) using Muskingum method and accordingly, the Design Flood was computed after adding the routed flood ordinates with flood ordinates of catchment C2. The total Design Flood (i.e. 2-Day PMF) with a peak of 15473 cumec was obtained. Conclusion: Even though, several factors are relevant while deciding the method to be used for design flood estimation, data availability and the purpose of study are the most important factors. Since, generally, we cannot wait for the hydrological data of adequate quality and quantity to be available, flood estimation has to be done using whatever data is available. Depending upon the type of data available for a particular catchment, the method to be used is to be selected.

Keywords: design flood, design storm, flood frequency, PMF, PMP, unit hydrograph

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