Journal Articles

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Enhancing cyber security awareness in maritime industry
(0000) Chandra, Mihir.
Cyber security is the combination of stakeholders, policies, processes and technologies to protect cyber assets of any industry. It is optimized to levels that help shipping personnel define, balance resources required with usability/manageability and the amount of risk offset. The aim of this paper is to develop understanding and awareness of key aspects of cyber security – identify threats, identify vulnerabilities, assess risk exposure, develop protection & detection measures & establish contingency plans. Furthermore, establish guidelines for operators on how to assess their ship’s operations & put in place necessary procedures and actions to maintain the security of cyber systems for marine industry. The integration of technology in shipping operations is being enabled by the integration of Information Technology and the Operation Technology on board ships. This has enhanced the threats of unauthorised access or malicious interventions to ship’s systems and networks. The measures to guard against cyber threats should include, (i) quantification and type of risks to security, environment and commerce if no cyber security measures are in place, (ii) due protection to IT and OT infrastructure and its networked equipment, (iii) management of access (iv) protecting data related with its sensitivity. With emerging technologies, there is a direct applicability of trends like Artificial Intelligence to enhance security and fraud prevention. Extending the use of Security Analytics for understanding and detecting risk level of vulnerabilities, improving the performance of own security policy by removal of unnecessary data, feature extraction and selection, data cut off, parallel processing, machine learning and deep learning algorithms – are some examples for the use of advanced technologies for improving Cybersecurity.
Review article on the mental health of seafarers
(0000) Chandra, Mihir.
‘Sea the future’ is coined correctly by the name blue economy. But is the future beckons wellbeing of the ‘key worker’? While Covid 19 pandemic halted most of the economic juggernauts in lockdown; it could not put a spanner into the propellers of ships which kept trading for 90% of the global trade 24x7 around the COVID’s variants year, seafarers mental and physical health went through tough times. The articles reviewed had never seen through this unknown tunnel of this decade. Wisdom of hindsight is common but resilience to bounce back may be grasped out of foresight with learnings of gap analysis. Awareness of factors influencing health, as a building block for seafarers’ training from pre-sea level is to be envisioned in the mode of compulsory courseware. Physical fitness and mental toughness modules must be enshrined in courseware with pedagogy and soft skill development through case studies. Research work should pave the way for innovative tools to monitor seafarer health 24X7. The well-being of seafarers may then be addressed potentially.
Use of swath data in realtime navigation by pattern recognition
(Marine Geodesy, 1989) Prabaharan, N.; Sivakholundu, K. M.
A new method is proposed with the aim of reducing dead reckoning error (DRE) during multibeam echosounding survey in deep ocean. Bathymetric data is used in this method to estimate DRE in position fixing. This method can be activated at any desired interval to check the DRE accumulation in addition to available external navigation systems. A pattern recognition algorithm is developed to quantify the shift in position of a selected bathymetric feature that has been observed already once. This difference is used to correct the position fixing and navigation data
Quantification of changes in seabed topography with special reference to Hansthal Creek, Gulf of Kachchh, India.
(Journal of costal research, 1993-01) Pattanshetti, S.S.; Chauhan, Onkar.; Sivakholundu, K. M.
Variations in the bathymetry in macrotidal Hansthal Creek between 1984 and 1950 along 14 closely spaced lines, are used to quantify the volumetric changes in seabed topography in terms of erosion/accretion. Two surfaces from the bathymetric data of 1984 and 1950 have been modelled. The profile wise comparison along the transects indicates a dynamic deformation due to distinct alteration in the shoreline and a shift in the channel course. The shoreline has retreated 650 and 450 m on the northern and southern banks respectively. The studies suggest scouring of horizontally deposited fine sediments (clays deposited in an antecedent depositional phase) in the Hansthal Creek due to existing dynamic equilibrium among (a) influence of physiography in amplifying the tidal range, (b) increased efflux due to contribution through inter-creek water movements, and (c) high magnitude currents. Magnitude of erosion in the creeks, particularly on the flanks, is much more than in the axial channel. The degree of the erosion reduces from the Hansthal Creek mouth to inland (area in the close vicinity of Little Gulf of Kachchh). During the last 34 years about 71.5 x 10 super(6) m super(3) from this creek during the course of the present study. Offshoreward movement of scoured sediments and their redeposition in the outer gulf as a fill in the paleo-channel is observed.
A program to compute the area of an irregular polygon on a spheroidal surface
(Computers and Geosciences, 1998) Sivakholundu, K. M.; Prabaharan, N.
A new archaeological find in the Gulf of Cambay, Gujarat
(Journal of the Geological Society of India, 2002) Kathiroli, S.; Badrinarayanan, S.; Venkata Rao, D.; Rajaguru, S.; Sivakholundu, K. M.; Sasisekaran, B.
Detailed underwater surveys carried out in the Gulf of Cambay, about 20 km west of Hazira, deploying side scan sonar and sub bottom profiler brought to light, the presence of a submerged palaeochannel traceable to a length of 9 km. Associated with this on either side are basement like features found in a grid pattern at water depths of 20-40 m. Sub-surface sampling carried out with dredge and grab sampler revealed stone artefacts, potsherds, hearth pieces, animal bones and human teeth embedded in fluvial sands and silts. In the upper part of the deposit, a carbonised wooden log was found and dated to around 9500 years BP by 14C method. Marine magnetic survey carried-out does not indicate the presence of any major metallic debrislobjects. This appears to be one of the early records of prehistoric human activity of early Holocene age in the marine environment of India.
Significance of income generation activities under micro-finance: A study of micro-finance groups in wayanad district, kerala
(Institute for Social and Economic Change, 2005) Mathew, Emil.
The present paper discusses the necessity of promoting income-generating activities (IGAs) under micro-finance programmes. Under micro-finance programmes, the principle of joint liability ensures access to credit. In the absence of remunerative IGAs, peer pressure forces the members to borrow loans from various sources at the time of repayment and results in indebtedness. The present paper examines the factors influencing the members to undertake IGAs and puts forth some policies to promote productive activities.
Does repayment indicate the success of micro-finance programme
(Institute for Social and Economic Change, 2006) Mathew, Emil.
This paper examines the patterns of loan utilisation and repayment among microfinance group members of Wayanad district of Kerala. It argues that 100 per cent repayment by members need not always indicate the success of group lending. As majority of the members have not undertaken income generating activities, the fear of social sanction and repeated interactions put pressure on them to depend on micro-finance loans at the time of repayment. The absence of alternative credit sources increases the financial dependence of the members over a period of their stay in micro-finance programme.
Estuarine channel stability assessment through tidal asymmetry parameters
(Journal of Coastal Research, 2009-03) Sivakholundu, K. M.; Mani J. S.; Idichandy V. G.; Kathiroli S.
In an estuarine channel the tidal asymmetry, sediment transport, and morphology are interconnected. To maintain a stable channel, we need to take tidal asymmetry into account. A relationship connecting tidal asymmetry and sediment transport rate has been used to evaluate the relative merits of channel modification through numerical simulations. Two criteria have been identified for ensuring the channel stability: (a) maintaining ebb dominance and (b) minimizing the spatial gradient in the net sediment transport function ⟨q⟩. Using these criteria for a test case, we have evaluated Hooghly estuary (east coast, India), where heavy sedimentation is experienced and a permanent solution is needed. The approach provides better insight into the sedimentation pattern in a semidiurnal tidal process in a shallow estuary with braided channels. Among the factors affecting tidal asymmetry, the relative phase difference (β) between M2 and M4 current constituents has a major influence and is thus responsible for the sedimentation pattern. Through numerical study it was found that a combination of deepened, uniform channel with enhanced ebb flow led to a favorable β, indicating less deposition.
Intra-annual studies of mixed layer depth in the Arabian Sea using a 3 ½ layer Indian ocean model
(Bentham Open, 2009-09-04) Patnaik, K. V. K. R. K.; Sreenivas, P.; Venkata Ramu, Ch.; Arun Kumar, S. V. V.; Prasad, K. V. S. R.
Mixed layer is the upper layer of the ocean, where significant physical, chemical and biological activities take place. Knowledge of mixed layer depth variability is important in the studies of air-sea interaction, acoustic propagation, heat transport and fisheries. The Arabian Sea experiences extremes in atmospheric forcing that lead to intra-annual and inter-annual variability. Since the climatic conditions over the Arabian Sea are highly variable, the mixed layer depth also changes seasonally. Hence the intra-annual variability of mixed layer depth in the Arabian Sea has been examined using 3 ½ layer Indian Ocean model. The model is integrated for 8 years (1993–2000) with annually varying monthly averaged winds derived from ERS-2 scatterometer. In addition to this data, inter annually varying monthly averaged satellite estimates of precipitation from Global Precipitation Climatology were also incorporated in the model. Model results show a steady deepening of mixed layer depth in the central Arabian Sea during southwest monsoon period. The model shows its capability to predict the shallow mixed layer depths caused by coastal upwelling off Somalia during southwest monsoon period and is able to capture the Lakshadweep high/low as it predicted successfully the deeper/shallow mixed layer observed during these periods.
Role of nearshore waves in identifying vulnerable zones during storm and normal events
(Enviroscan, 2010) Arun Kumar, S. V. V.; Prasad, K. V. S. R.; Patnaik, K. V. K. R. K.; Venkata Ramu, Ch.; Sreenivas, P.
During the SW Monsoon season, the average nearshore wave energy 3 along the coast is higher for the stations 3 and 20 with values 4.3 x10 2 J/m (Fig. 2). From the southern end of the coast, the wave energy is 3 2 decreasing having a least value of 2.2 x10 J/m in the Lawson's Bay (station 13). Hence, during this season, RK Beach, Jodugullapalem Beach and Sagar nagar Beach are the high energetic zones and so there is a possibility of erosion at these places.
Relevance of Information Technology in Knowledge Management
(INFOLIB, 2010) Mishra, Anil Kumar
Knowledge management has been recognized as a one of the most important assets of organizations. It also plays a crucial role in avoiding the organization in a calamitous position of being with the wrong product and services, at the wrong time and in the wrong place.
Protection and voltage control of DFIG wind turbines during grid faults /
(IEEE, 2010-01-01) Das, Milton Kumar
The fault ride-through and grid support capabilities of the doubly fed induction generator (DFIG) wind turbines mainly address the design of DFIG wind turbine control with emphasis on power converters protection and voltage control issues. This paper presents the development of a protection and voltage control strategy for DFIG wind turbines, which enhances the fault ride-through capability of DFIG wind turbines and their ability to provide voltage control during grid faults. The performance of the proposed protection and voltage control strategy is assessed through the simulations of a 2MW DFIG wind farm. To protect the rotor side converter, a crowbar at the rotor is switched on. The performance of an active crowbar during voltage dips is investigated for several parameter sets of machine, resistor and control.
Validating AHP, fuzzy alpha cut and fuzzy preference programming method using clustering technique /
(Springer Nature, 2010-03-01) Mitra, Kalyan
Fuzzy multicriteria analysis (MA) methods suitable for a given decision problem usually differ in aggregation processes for handling the alternatives’ performance ratings and criteria weights. Due to their structural differences, these methods often produce inconsistent ranking results for the same fuzzy MA problem. This paper presents a validation procedure using fuzzy clustering for selecting among inconsistent ranking results produced by analytical hierarchy process (AHP), fuzzy alpha cut and fuzzy preference programming (FPP) methods for a given problem. The procedure compares the ranking results obtained by fuzzy MA methods using different aggregation algorithms with the clustering results of the alternatives by fuzzy clustering. An empirical study of evaluating major port trusts of India is conducted to demonstrate the effectiveness of the validation procedure.
Variation of resonant frequency of a rectangular microstrip patch antenna due to accumulation of water over its surface /
(IEEE, 2010-08-01) Chakraborty, Samik
In the work presented here, the effect on the resonant frequency of a rectangular microstrip patch antenna-due to accumulation of water over its microstrip patch surface-during rainy seasons is studied. A probe-fed rectangular microstrip patch antenna having dimensions 84 mm × 70 mm (W × L), fabricated on the Duroid® substrate (εr = 2.4) of thickness 1.524 mm (60 mill) and resonant frequency equal to 1.34 GHz, is used for the experiment. The antenna is assumed to be in outdoor condition such that the microstrip patch surface lies horizontal so that water may be accumulated over its surface during rainy conditions. This effect is emulated by pouring distilled water over the antenna patch surface to form a water layer of uniform thickness successively of 1 to 5 mm-and its effect on the resonant frequency of the antenna is observed. An empirical relation between percentage change in resonant frequency and the height of water layer over the rectangular microstrip patch antenna surface is presented.
Contribution of tides to sea level variations along Visakhapatnam, India
(Taylor & Francis, 2010-08-07) Prasad, K. V. S. R.; Sreenivas, P.; Patnaik, K. V. K. R. K.
The sea level variations along Visakhapatnam coast are governed by astronomical tides and nontidal oscillations including atmospheric pressure, winds, coastal currents, Ekman Pumping, and river influx. Tidal and nontidal sea level oscillations are usually studied separately because of the vastly different ways in which they are forced. In this study the tidal oscillations along Visakhapatnam are analyzed using GOTIC2 tidal model. The correlation between monthly mean sea level and monthly mean tides is 47% (r = 0.68) and increases to 54% (r = 0.74) when applied for inverse-barometric effect. The major six partial tides are computed and presented. The tidal variations from Neap tide to Spring tide are studied.
Control of biocorrosion to prevent the propagation of invasive species
(Indian Maritime University, Chennai, 2010-09) Joshi, Madhu; Mukherjee, A.; Ramesh, U. S.; Misra, S. C.
Biocorrosion or biofouling on ships hull occursdue to the attachment of barnacles, mollusks and other aquatic organisms on the surface of ships which leads to increase in fuel consumption, reduction of the vessels speed, premature failure of the hull, etc. Recent developments in antifouling paints, in general, prevent fouling in about 95% percent of the vessels underwater surface, which ship operators find satisfactory as far as the routine vessel operation is concerned. However, this is not sufficient to prevent the transport or invasion of alien species. In recent years the issue of invasive marine species has been receiving considerable attention due to the fact that introduction of nonidegenous species or non-native species transmigrated from other areas to coastal waters often results in the reduction and even extinction of the native species and thereby severely disrupting the natural marine ecosystems. The predominant vector for the transport of nonindigenous species in marine environments has been shipping. While ballast water receives the most attention, hull fouling is now considered to be the most significant means for translocation of these organisms. For example, 90 percent of the 343 marine alien species in Hawaii are thought to have arrived through hull fouling Certain niche areas of the vessel such as bow thrusters, sea chest, stern tube, rudder etc. are the likely areas to be heavily fouled. In addition, the other areas that are likely to be fouled are on locations where antifouling paint has been worn of due to excessive shear and bending of the hull. This paper reviews the various antifouling strategies and aims identify areas on the hull surfaces of certain classes of vessels that are prone to fouling by excessive shear and bending and identify suitable antifouling treatments to further reduce the risk of transportation of alien species.
Issues in offshore platform research - Part 1: Semi-submersibles
(Elsevier, 2010-09-01) Misra, Sudip C.
Availability of economic and efficient energy resources is crucial to a nation's development. Because of their low cost and advancement in drilling and exploration technologies, oil and gas based energy systems are the most widely used energy source throughout the world. The inexpensive oil and gas based energy systems are used for everything, i.e., from transportation of goods and people to the harvesting of crops for food. As the energy demand continues to rise, there is strong need for inexpensive energy solutions. An offshore platform is a large structure that is used to house workers and machinery needed to drill wells in the ocean bed, extract oil and/or natural gas, process the produced fluids, and ship or pipe them to shore. Depending on the circumstances, the offshore platform can be fixed (to the ocean floor) or can consist of an artificial island or can float. Semi-submersibles are used for various purposes in offshore and marine engineering, e.g. crane vessels, drilling vessels, tourist vessels, production platforms and accommodation facilities, etc. The challenges of deepwater drilling have further motivated the researchers to design optimum choices for semi-submersibles for a chosen operating depth. In our series of eight papers, we discuss the design and production aspects of all the types of offshore platforms. In the present part I, we present an introduction and critical analysis of semi-submersibles.
Issues in offshore platform research - Part 1: Semi-submersibles /
(SNAK, 2010-09-30) Misra, S.C.
Availability of economic and efficient energy resources is crucial to a nation's development. Because of their low cost and advancement in drilling and exploration technologies, oil and gas based energy systems are the most widely used energy source throughout the world. The inexpensive oil and gas based energy systems are used for everything, i.e., from transportation of goods and people to the harvesting of crops for food. As the energy demand continues to rise, there is strong need for inexpensive energy solutions. An offshore platform is a large structure that is used to house workers and machinery needed to drill wells in the ocean bed, extract oil and/or natural gas, process the produced fluids, and ship or pipe them to shore. Depending on the circumstances, the offshore platform can be fixed (to the ocean floor) or can consist of an artificial island or can float. Semi-submersibles are used for various purposes in offshore and marine engineering, e.g. crane vessels, drilling vessels, tourist vessels, production platforms and accommodation facilities, etc. The challenges of deepwater drilling have further motivated the researchers to design optimum choices for semi-submersibles for a chosen operating depth. In our series of eight papers, we discuss the design and production aspects of all the types of offshore platforms. In the present part I, we present an introduction and critical analysis of semi-submersibles.
Performance of tobacco oil-based bio-diesel fuel in a single cylinder direct injection engine
(International Journal of the Physical Sciences, 2010-10) Satyanarayana Murthy, Y. V. V.
In the present investigation, the high viscosity tobacco oil, which has been considered as non-edible oil as a potential alternative fuel for the Compression Ignition Engine (C. I.). Tobacco Methyl Ester (TME) was prepared by transesterification of raw tobacco oil. A two stage transestirification process was developed since tobacco is having higher acidic value. Transesterification was done using NaOH in the presence of sulphuric acid as catalyst and both acid transesterification and base transestirification was performed. Since TME has higher kinematic viscosity, its viscosity has been reduced by blending with neat diesel. The bio-diesel was blended with neat diesel at various volumetric proportions of B2, B5 (denoting 2, 5%) .The performance of this alternate fuel was tested by conducting a series of tests on 4 stroke single cylinder 5.2 kW direct injection diesel engine. The engine was run at different loads like full load, 3/4, 1/2, 1/4 and no load at various speeds and also at constant speed .The tests were conducted by using neat diesel and also diesel fuel blended with TME The combustion characteristics and exhaust emissions like hydrocarbon (HC), carbon (II) oxide (CO) and nitric oxides (NO) were measured. Torque, brake power, specific fuel consumption was also measured and the test was plotted in the graphs. The physical and chemical specifications like flash point, fire point, density, kinematic viscosity and acid number of TME were established. Significant improvement in engine performance was observed. The specific fuel consumption and the exhaust gas temperature reduced due to the decrease in viscosity of TME. From the properties and engine test results it has been established that at lower percentage of blending, TME has improved the engine performance but at higher percentages of blending, the performance and engine emissions were drastically effected. The results show that the TME can be used as an alternate fuel in diesel engines without any engine modifications.