Browsing by Author "T.N. Singh"

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A comparative study of artificial neural network and multivariate regression analysis to analyze optimum renal stone fragmentation by extracorporeal shock wave lithotripsy.
(2010) Neeraj K Goyal; Abhay Kumar; Sameer Trivedi; Udai S Dwivedi; T.N. Singh; Pratap B Singh
To compare the accuracy of artificial neural network (ANN) analysis and multi-variate regression analysis (MVRA) for renal stone fragmentation by extracorporeal shock wave lithotripsy (ESWL). A total of 276 patients with renal calculus were treated by ESWL during December 2001 to December 2006. Of them, the data of 196 patients were used for training the ANN. The predictability of trained ANN was tested on 80 subsequent patients. The input data include age of patient, stone size, stone burden, number of sittings and urinary pH. The output values (predicted values) were number of shocks and shock power. Of these 80 patients, the input was analyzed and output was also calculated by MVRA. The output values (predicted values) from both the methods were compared and the results were drawn. The predicted and observed values of shock power and number of shocks were compared using 1:1 slope line. The results were calculated as coefficient of correlation (COC) (r2 ). For prediction of power, the MVRA COC was 0.0195 and ANN COC was 0.8343. For prediction of number of shocks, the MVRA COC was 0.5726 and ANN COC was 0.9329. In conclusion, ANN gives better COC than MVRA, hence could be a better tool to analyze the optimum renal stone fragmentation by ESWL.
Analysis of failure pattern in cut slopes of bedded sandstone: a case study
(Springer Science and Business Media Deutschland GmbH, 2022) Digvijay Singh; P.K. Singh; A. Kainthola; H.K. Pandey; Saurabh Kumar; T.N. Singh
Anisotropic sedimentary rocks are common around the world. Several factors, such as presence of primary and tectonic structures, type of weathering and rate of cohesion loss due to strength degradation, have significant effect on stability of slopes. In the present research, Geological strength index (GSI) has been used for quantitative comparison of rock mass quality and to investigate the rock mass damage. Other indicators of rock mass strength degradation, such as slake durability index tests, weathering index, were studied to understand the loss of strength with time leading to progressive failure in slopes. The failure pattern in bedded sandstones is controlled by bedding inclination, primary structures, vertical fractures. Folding affects bedding plane inclination and modify the failure mode along cut slopes. The cross-stratification significantly reduces rock quality and creates overhangs. The shape and size of overhangs are controlled by the presence of vertical cracks in addition to the type and scale of cross-stratification and failure generally occurs by block fall rather than block slide. The peculiar steeply plunging wedges associated with vertical fractures are very common in sub-horizontal bedded sandstone. Failure usually occurs by wedge fall rather than slide. Differential weathering affects the pinching strata against the massive beds and the characteristic wedges are common occurrence above this considerably fractured zone. Tectonic structures such as folds modify the style of failure in rock slopes as seen from kinematic analysis. The overall trend of lineaments is parallel to the strike of bedding plane (roughly E-–W) and the lineaments may be associated with reactivation of the major fault passing through the area. This study illustrates that the impact of tectonic damage further enhances the strength degradation caused by weathering, and climatic slaking. Overall rock mass quality lies in good to fair category, but preliminary stability analysis depicts slope in partially stable to unstable condition along SH-5; however, rock mass quality and cut slopes are relatively stable along SH-5A. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Artificial neural networks in predicting optimum renal stone fragmentation by extracorporeal shock wave lithotripsy: A preliminary study
(2003) A. Hamid; U.S. Dwivedi; T.N. Singh; M. Gopi Kishore; M. Mahmood; H. Singh; V. Tandon; P.B. Singh
OBJECTIVE: To assess the ability of artificial neural networks (ANNs) to predict optimum renal stone fragmentation in patients being managed by extracorporeal shock wave lithotripsy (ESWL). PATIENTS AND METHODS: The study included 82 patients with renal stones who were being treated by ESWL. Data (input and output values) from 60 patients in whom there was optimum fragmentation of stones by ESWL were used for training the ANN. These data mainly included the 24-h urinary variables, the radiological features of the stone disease and the ESWL settings used. The predictability of the trained ANN was tested on 22 subsequent patients, by supplying the input variables of the 22 patients into the trained ANN and recording the output values (predicted values). After subjecting these patients to ESWL, the actual results (observed values) were recorded. The predicted and the observed values were then compared. RESULTS: In the 22 patients in whom predictability was tested, the trained ANN predicted optimum fragmentation at ≤13 000 shocks/stone (as per study protocol) in 17 and optimum fragmentation at >13 000 shocks/stone in the other five. In the 17 patients (test set) where the trained ANN had predicted optimum fragmentation at ≤13 000 shocks/stone, the optimum fragmentation was at that value, although the predicted and observed values were not identical. The overall correlation between the predicted and the observed values was 75.5% (correlation coefficient 0.7547) in these 17 patients. Of the other five patients, none had optimum fragmentation at <13 000 shocks/stone, as predicted by the trained ANN, giving complete accuracy for this factor. CONCLUSION: This was a pilot study, i.e. an initial attempt to use an ANN in this regard, and although there were few patients, such that it is not possible to make final recommendations, the overall predictability was ≈75%. An encouraging outcome of the study was that the trained ANN identified patients unlikely to benefit from ESWL. Using a larger dataset and identifying more significant variables, while eliminating inputs with a negative effect, the efficiency and utility of this ANN can probably be enhanced and in future it might be possible to predict stone fragmentation with reasonable accuracy.
Assessment of Karmi Landslide Zone, Bageshwar, Uttarakhand, India
(Springer, 2020) V.N. Tiwari; V.H.R. Pandey; Ashutosh Kainthola; P.K. Singh; K.H. Singh; T.N. Singh
Slope instability is a big challenge for the population in mountainous regions. It poses a threat to life, economy, and infrastructure. For the safety of people, various prevention and precautions are taken and hence many scientific studies are going on. In the present study, the stability of the Karmi landslides zone, Bageshwar, Uttarakhand, India is assessed. Karmi village lies quite close to the northern border of India and the excavated roads are the only means of commute. The area lies in a tectonically active lesser Himalayan zone with high relief. Slope geometry was extracted using a total station, and seven different slope geometries were plotted. Soil and rock mass samples were taken and evaluated from various field and laboratory investigations. The direct shear test was performed to assess the friction angle and cohesion of the soil and rock mass. Numerical simulations viz., finite element analysis and probabilistic analysis have been applied on all seven slope sections and found that the mean and median safety factor of all the modeled slopes was 0.78 and 0.81, respectively. The study ascertains that the whole area to be quite vulnerable to failure, especially during rains, since the pore pressure build-up diminishes the shear strength of the slope forming material. Possible mitigation measures have been suggested based on the examined instability of the hill slopes. © 2020, Geological Society of India.
Boundary element coupled structural analysis of Lesser Himalayan railway tunnels: A case study of the Shivpuri–Byasi section, Rishikesh–Karnaprayag BG rail link, Uttarakhand, India
(Springer, 2024) Abhishek Srivastav; Vikas Yadav; Ashutosh Kainthola; Vishnu H R Pandey; Vijay Dangwal; T.N. Singh
A tunnel provides reliable, low-maintenance, and all-weather connectivity in hilly terrains. Rishikesh–Karnaprayag Broad Gauge project is a 125 km long rail link, that includes 35 bridges and 17 tunnels, to connect the tough route of Uttarakhand Chardham sites. This tunnel route passes through the Lower Himalayas of Uttarakhand, India. The present research emphasizes the structural discontinuities’ influence on tunnel stability at different chainages (18570 to 32000) with a 13.4 km long span, having variable overburden and rock mass conditions. The factor of safety is determined using kinematic analysis and numerical simulation based on the boundary element method. The boundary element method examines the excavation problems and captures the interaction of the tunnel structure and surrounding rock mass. Different rock mass classification schemes are also utilized to evaluate the rock mass conditions. Schemes mainly include rock mass rating (RMR), Q-system and Ö-NORM B2203 (NATM class), suggesting that the rock mass quality ranges from poor to fair. The factor of safety for critically unstable wedges without support varies between 0.49 and 0.98, and after applying shotcrete and rock bolting, FOS varies between 0.63 and 3.23. In the present study, the overburden varies between 33 and 590 m. The influence of applied computational support (shotcrete and rock bolting) has been studied with an average value of factor of safety at each 100 m interval. The study outcomes may be significant in supporting estimation during similar rock mass conditions. © Indian Academy of Sciences 2024.
Comparative study of the deformation modulus of rock masses—a reply to the comments received from Gokceoglu (2018)
(Springer Verlag, 2018) Suman Panthee; P.K. Singh; Ashutosh Kainthola; Ratan Das; T.N. Singh
Availability of information on the deformation modulus in the initial stages of civil engineering projects related to near-surface or underground excavation is very important for design purposes. However, direct determination of the deformation modulus is a challenging task and a potentially costly one; therefore, several researchers have frequently used indirect methods to assess the deformation modulus. Of the significant number of empirical equations that can be found in literature, most are non-linear, which makes the deformation modulus a parameter that is very sensitive to the quality and types of data used. © 2018, Springer-Verlag GmbH Germany, part of Springer Nature.
Compressive strength and tensile strength of rocks at sub-zero temperature
(1998) R.D. Dwivedi; P.K. Singh; T.N. Singh; D.P. Singh
The present paper deals with the uniaxial compressive and tensile behaviour of Chunar sandstone and Makrana marble at sub-zero temperature (0°C to -20°C) in dry and wet conditions. It was found that uniaxial compressive and tensile strengths of these rocks increased with decrease in temperature below 0°C. Both strengths in general and tensile strengths in particular of wet rocks increased more rapidly in comparison to dry rocks.
Critical appraisal of pillar design as required by Coal Mines Regulations of India vis-vis latest rockmechanics formulae
(Publ by Australasian Inst of Mining & Metallurgy, 1992) S.K. Sharma; T.N. Singh; D.P. Singh
The present study attempts to critically review the pillar-design as required by Coal Mines Regulations of India vis-a-vis latest rockmechanics formulae. Equivalent material modelling was the approach adopted for testing the safety and stability of the pillar sizes predicted by various formulae. Two parameters, considered here for calculating pillar sizes was the stresses acting over the pillars and the strength of the pillars. Stresses acting on the pillars were calculated by the tributary area method. Based on the studies of Coates and Hustrulid, the stress obtained was reduced by 40 percent. For calculating the strength of the pillars, three formulae, namely Holland and Gaddy, Salamon and Munro and Central Mining Research Station, India, were used. The pillar widths were then determined by equating the product of recommended factor of safety and pillar stress with the pillar strength.
De Launay's angular force model for β-SiC
(1973) T.N. Singh; S.S. Kushwaha; G. Singh
Phonon dispersion relations of β-SiC along [100] and [111] directions have been calculated using de Launay's angular force model. The noteworthy features of the present approach are that the number of parameters used is comparatively smaller and Si-Si and C-C interactions are taken to be different. The agreement between the theoretical and experimental results is reasonably good. © 1973.
Deep learning models for large-scale slope instability examination in Western Uttarakhand, India
(Springer Science and Business Media Deutschland GmbH, 2022) Vishnu Himanshu Ratnam Pandey; Ashutosh Kainthola; Vikram Sharma; Abhishek Srivastav; T. Jayal; T.N. Singh
Slope failures are avoidable accidents in most of the scenarios. The eventuality of a failure leads to loss of lives and destruction, especially in hilly areas. Investigation, analysis and prediction of slope failure is a reliable approach to avert such mishaps. Hence, the present research work delves into the prediction of landslides and slope failures through numerical simulation and a deep learning approach. Field attributes and laboratory-tested strength data from Lower Tons Valley, Northern India has been taken as a case study. Initially, a total of 185 slope models were simulated in a finite difference code by varying four slope parameters, namely, slope angle, slope height, cohesion and angle of internal friction. These simulated results were further divided into two parts, one part with 148 datasets for the training of models and other part consisting of 37 datasets for testing of models. Two artificial neural network prediction models, along with a conventional multi-linear regression model was developed and their accuracy was accessed. The developed neural network models superseded the conventional model, in terms of performance and accuracy, as shown by statistical approaches R2 and mean squared error values. Moreover, the neural network model with Adam optimizer achieved higher statistical accuracy than the one with stochastic gradient descent optimizer. However, all these deep learning models demonstrate significant performance, and can be used by geo-engineers for swift prediction of safety factors for excavated slopes in the study area. © 2022, The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.
Discontinuity-Induced Partial Instability in Markundi Hills, Sonbhadra, Uttar Pradesh, India
(Springer Science and Business Media Deutschland GmbH, 2024) Vikas Yadav; Ashutosh Kainthola; Vishnu H. R. Pandey; Gaurav Kushwaha; T.N. Singh
State Highway-05A in Northern India, connects the states of Chhattisgarh, Madhya Pradesh, Uttar Pradesh, and Jharkhand. In Uttar Pradesh, it passes through steep and rugged Markundi Hill, composed of highly jointed sandstone. The current study examines road-cut slopes at six locations to quantify the instability mechanism and slope health. Detailed field and laboratory investigations were combined to ascertain the structural, petrographic, and strength attributes of the rock. Afterwards, data was collated to characterise the rockmass behaviour through widely accepted classification schemes, viz., geological strength index (GSI), Q-slope, rock mass rating (RMR), slope mass rating (SMR), and modified global slope performance index (modified GSPI). The value ranges provided by various empirical classifications are 40–62 (RMR), 39.61–58.46 (SMR) and modified 44.57–52.57 (GSPI). For structural stability, kinematic analysis was conducted. According to RMR, five locations fall in fair and one in poor rockmass classes. SMR suggest all locations are partially stable. Eventually, a novel approach for finding the ratings of GSPI is also introduced in the present work, allowing more comprehensive discontinuity characteristics incorporation. The new approach brings GSPI and SMR to the same scale, making it easy to compare the two. GSPI yields that all the locations have high chances of local bench failures. Compared to other approaches, GSPI predicts a wide range of instabilities and should be used alone or in conjunction with other systems for slope stability assessment. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.
Effect of Petrographic Properties on the Strength Parameters of Indian Metamorphic Rocks
(Springer Science and Business Media Deutschland GmbH, 2022) A.K. Verma; Amit Jaiswal; T.N. Singh
The geotechnical properties of any rock are affected by its mineral composition, alteration, weathering, and micro structures of the rock. Limited experimental validation of the existing correlation between petrographical and physico-mechanical properties of rocks inhibits practical use of petrographical thin sections to determine the strength properties. In this study, the extensive analysis of thin sections shows that the quartz has a positive correlation with UCS in the rock samples while presence of K-feldspar, Plagioclase and Biotite shows negative correlation with UCS of different rock types. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Empirical and Numerical Evaluation of a Cut Slope Near Rishikesh, India
(Springer Science and Business Media Deutschland GmbH, 2022) V.H.R. Pandey; Ashutosh Kainthola; T.N. Singh
The stability analysis of cut slopes along any transportation corridor is necessary to safeguard people’s and societal interests. The present work presents assessment of a steep rock cut slope near Rishikesh, along a national highway in Uttarakhand, India. The work details empirical and numerical examination of the slope stretching approximately 20 m in length along the road. The field investigation has been undertaken to ascertain discontinuities conditions, their orientations, spacing between them, geological strength index as well as slope geometries. Three joint sets were recorded with spacing of 10–120, 5–45, 6–35 cm respectively, with slope angle of 75° and slope height equal to 65 m. Moreover, the rock samples were taken in laboratory to further discern required geotechnical parameters such as unconfined compressive strength, Young’s modulus, and Poisson’s ratio etc. The empirical and numerical techniques were applied to examine the slope’s health. Q-slope and Slope Mass Rating were the employed empirical method. Besides, the finite element approach was adopted to assess the slope stability numerical. Finally, outcomes of all these scientific assessments were compared with each other and ground reality. The Q-slope values achieved was 1.58 for the concerned slope, while the SMR value was 37. Finite element simulation yielded a safety factor of 1.6 for the dry condition. Furthermore, kinematic analysis of slope shows the possibility of planar and wedge modes of failures. Keeping in view the attained results, the slope should be excavated at an angle of 69°, while also making provisions for drainage of rain water. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Geotechnical and micro-structural characteristics of phyllite derived soil; implications for slope stability, Lesser Himalaya, Uttarakhand, India
(Elsevier B.V., 2021) T. Ansari; Ashutosh Kainthola; K.H. Singh; T.N. Singh; M. Sazid
Collapses of hill slopes along critical roadways are of dire consequence. Large literature is available on the stability assessment of hill slopes composed of rock and soils; however, a lacuna exists when it comes to geotechnical appraisal and instability aspects of slopes composed of in-situ saprolitic soils. The present study examines the physical, micro-structural and geotechnical characteristics of soil derived phyllite, and its ensuing influence on the instability of hill slopes at certain sections along National Highway-7, Uttarakhand, India. Four distinct locations along the highway were selected for the study. After field survey, the laboratory investigation was carried out to ascertain the geotechnical, chemical and mirco-structural parameters of the representative phyllitic soil samples. Eventually, stability analysis was carried out using Limit Equilibrium Method, Finite Element Method, and Finite Difference method, for the four locations. The analysis for location 2 & 4 showed them to be in a critical - unstable state, whereas, location 1 & 3 demonstrated stability in the present state. Compared to other techniques, FDM analysis results were in close congruence with the ground truth. The present study also sheds significant insight into the composition and deformation behaviour of the soils derived from the weathering of phyllite. The research may have enormous ramifications for the future assessment of similar soils and their possible use as admixtures in construction industry. © 2020 Elsevier B.V.
Influence of pH of water on mechanical properties of sandstone - An experimental approach
(2000) R.K. Dubey; T.N. Singh
The cylindrical NX size Chunar sandstone samples are prepared from collected sandstone blocks of Chunar locality, District Mirzapur, U.P. These are submerged in water having different pH values. The water saturated samples of sandstone are deformed on close loop servo-controlled auto - feed back Material Testing System (MTS). The dry samples of sandstone are also deformed on the MTS.The experimental study suggests that the compressive strength, tensile strength, shear strength, and cohesive strength observed in sandstone increases with increases in pH of water, while the angle of friction decreases with increases in pH of saturated medium, i. e., water.
Metabolic drift as internal defense against drought in crop plants: Evidence unlocked from rice cultivars
(2009) Sanjay Singh; T.N. Singh; J.S. Chauhan
We chose three rice (Oryza sativa L.) cultivars to understand the physiology of crop adaptation to drought. Under water stress, leaves curled up and rolled in and the water potential declined. 'Baranideep' maintained relatively higher water potential (-1.8 MPa) than irrigated hybrid rice cv. 'NDRH-2' (-2.0 MPa) and aquatic cv. 'Jal Lahri' (-2.6 MPa). The drought-induced stress caused variation in tissue-specific expressions of metabolic drift in sugar and starch, protein, and nitrogen, and stay-green traits. The genotypic differences in sugar levels varied to the extent of 130 mg g-1 fresh wt (f.w.) in 'Jal Lahri' >120 mg in 'NDRH-2' 114> mg in 'Baranideep', while initial starch contents were 263 mg >252 mg >230 mg in these cultivars, respectively. Sugar levels rose by 23% in cv. 'Jal Lahri', 16% in 'NDRH-2' and 17% in cv. 'Baranideep', whereas starch contents declined by 17%, 13% and 12.5%, respectively. The net chlorophyll concentrations were highest in 'NDRH-2' (up to 1,325 μg g-1 f.w.), followed by 'Jal Lahri' (1,050 μg) and 'Baranideep' (920 μg) under normal conditions, but declined during water stress; 'NDRH-2' maintained its superiority over the other varieties. Under water stress, chlorophyll a:b ratios increased appreciably in 'Baranideep'; 'Jal Lahri' registered the largest difference between watered and stressed plants. 'Baranideep' accumulated the largest amount of proline (9.25 mg g-1 dry wt) during water stress. Under non-stress conditions, 'NDRH-2' had the highest nitrogen content in leaves (2.15%), followed by 'Jal Lahri' (1.85%) and 'Baranideep' (1.75%). The cv. 'NDRH-2' retained more nitrogen in leaves than other cultivars. 'Jal Lahri' retained the highest nitrogen in the shoot. Nevertheless, under drought stress, the shoot protein was highest in 'NDRH-2' (3.15%), followed by 'Baranideep' (2.80%) and 'Jal Lahri' (2.65%). These tissue-specific metabolic drifts are plant's life-support system and serve as a defense against drought.
Numerical Analysis of a Collapsed Tunnel: A case study from NW Himalaya, India
(Springer, 2022) A. Srivastav; V.H.R. Pandey; A. Kainthola; P.K. Singh; V. Dangwal; T.N. Singh
The present research explores the effect of various support system on deformation in a shallow tunnel from North-Western Himalaya, India. The deformation measurements assessed through field investigation were utilized to simulate the pre-existing and the present ground scenario, and furthermore in the evaluation of elastic parameters such as Young’s modulus and Poisson’s ratio through finite element back analysis. Back-analysed model predicted a Young’s modulus of 32 MPa and Poisson’s ratio of 0.3. Afterwards, the effect on the deformation of surrounding groundmass for unexcavated and the present condition were numerically ascribed at three different stages of excavation. The numerical application of forepoling and steel liners showed a marked reduction in the tunnel deformation. The combined effect of applied support methods was also enumerated and compared with individual stabilization method. This assessment may aid engineers and planners working in similar geological conditions, by making the excavation safer, stable and economical. © 2021, Indian Geotechnical Society.
Parametric Study of Influence of Groundwater and Joint Spacing on Stability of a High Overburden Tunnel
(Springer Science and Business Media Deutschland GmbH, 2022) A. Srivastav; Ashutosh Kainthola; V. Dangwal; T.N. Singh
In a complex terrane, excavation engineers have to take into account various problems and challenges. Himalaya is rugged with highly undulating topography, major discontinuous boundaries, extremely heterogenous lithology and complex subsurface water system, which makes the excavation process more troublesome in it. Groundwater decreases the strength of the rock mass through increase in pore-water pressure and decrease in effective stresses. The Present research is based on estimation of influence of groundwater and discontinuity spacing on tunnel stability through field deformation and numerical simulation. The study site is part of Rishikesh-Karnaprayag railway project in Uttarakhand Himalaya. The tunnel has the diameter of 7.8 m with the overburden depth of 200 m. Sandstone rocks surrounding the excavation boundary belong to Mandhali formation. Initially, numerical model was simulated using the properties of discontinuities exposed at the tunnel phase and the mean properties of Borehole log data nearest to the excavation site. Afterward, deformation is calibrated at different water pressure heads and various discontinuity spacings. The variation in deformation is significant with variation in groundwater pressure and discontinuity spacing and reveals the importance of these parameters during underground excavation and stability assessment. © 2022, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.
Physico-Mechanical Characteristics of Vindhyan Sandstone, India
(Springer, 2022) V. Chaudhary; A. Srivastav; V.H.R. Pandey; Ashutosh Kainthola; S.K. Tiwari; S.B. Dwivedi; T.N. Singh
Quick and reliable estimation of intact rock strength parameters is vital for the excavation and stability measurement. The present research details the assessment of a few physico-mechanical parameters of sandstone rocks from Eastern India, and their statistical correlation and swift prediction. The dataset consists of 150 experimentally evaluated values for dry density, porosity, uniaxial compressive strength, tensile strength and Young’s modulus. Afterwards, the data were analyzed in the statistical environment “R” for correlation and distribution. For the ease of usage and implementation, density and porosity have been used as explanatory variables for the prediction of strength attributes. Initially, univariate linear regression models were devised, which yielded a coefficient of determination ranging between, 0.5 to 0.73. However, the r2 increased, in a range between 0.69 and 0.74, when multivariate analysis using the same independent variables was performed. In the present work, investigations and analysis have been done to predict the uniaxial compressive strength, tensile strength and Young’s modulus with dry density and porosity. Moreover, the statistical significance of the study has been discussed and compared with previous work. The present research can be used as a means to quickly and economically estimate strength parameters in the absence of a sophisticated testing setup. © 2021, The Institution of Engineers (India).
Prediction of biochemical failure in localized carcinoma of prostate after radical prostatectomy by neuro-fuzzy
(Medknow Publications and Media Pvt. Ltd, 2007) Neeraj Goyal; Abhay Kumar; Rajiba L. Acharya; Udai Dwivedi; Sameer Trivedi; Pratap Singh; T.N. Singh
Objective: To predict biochemical failure in localized prostate cancer after radical prostatectomy using preoperative variables. Materials and Methods: Twenty-six patients of early carcinoma of prostate underwent open retropubic radical prostatectomy from June 2002 to June 2006. Preoperative variables included age, family history, digital rectal examination, serum prostatic specific antigen (S. PSA), prostate biopsy Gleason score, MRI of pelvis variables like periprostatic extension, seminal vesical invasion, weight of gland and pathological stage. With application of neuro-fuzzy, these variables were fed into system as input and output, that is S. PSA at six months (predicted value) was calculated. Neuro-fuzzy system is a system to combine fuzzy system with learning techniques derived from neural networks. Here, we applied Takagi Sugeno Kang model (TSK) due to its close solution to our aim. All the patients were followed up for a minimum of six months. At six month S. PSA of all patients was done (observed value). Predicted and observed values were compared. Result: Predicted and observed values were plotted on 1:1 slop line. Coefficient of correlation was 0.9935. Conclusion: Coefficient of correlation is close to one. It indicates that the neuro-fuzzy is accurate in predicting biochemical failure in localized carcinoma of prostate after radical prostatectomy.