Survey on Encryption Techniques in Delay and Disruption Tolerant Network

Delay and disruption tolerant network (DTN) is used for long area communication in computer network, where there is no direct connection between the sender and receiver and there was no internet facility. Delay tolerant network generally perform store and forward techniques as a result intermediate node can view the message, the possible solution is using encryption techniques to protect the message. Starting stages of DTN RSA, DES, 3DES encryption algorithms are used but now a day\u27s attribute based encryption (ABE) techniques are used. Attribute based encryption technique can be classified in to two, key policy attribute based encryption (KPABE) and cipher policy attribute based encryption (CPABE). In this paper we perform a categorized survey on different encryption techniques presents in delay tolerant networks. This categorized survey is very helpful for researchers to propose modified encryption techniques. Finally the paper compares the performance and effectiveness of different encryption algorithms

Stress Urinary Incontinence post-Holmium Laser Enucleation of the Prostate: a Single-Surgeon Experience.

PURPOSE: To identify incidence and predictors of stress urinary incontinence (SUI) following Holmium laser enucleation of the prostate (HoLEP). MATERIALS AND METHODS: We performed a retrospective review of 589 HoLEP patients from 2012-2018. Patients were assessed at pre-operative and post-operative visits. Univariate and multivariate regression analyses were performed to identify predictors of SUI. RESULTS: 52/589 patients (8.8%) developed transient SUI, while 9/589 (1.5%) developed long-term SUI. tSUI resolved for 46 patients (88.5%) within the first six weeks and in 6 patients (11.5%) between 6 weeks to 3 months. Long-term SUI patients required intervention, achieving continence at 16.4 months on average, 44 men (70.9%) with incontinence were catheter dependent preoperatively. Mean prostatic volume was 148.7mL in tSUI patients, 111.6mL in long-term SUI, and 87.9mL in others (p \u3c 0.0001). On univariate analysis, laser energy used (p \u3c 0.0001), laser on time (p=0.0204), resected prostate weight (p \u3c 0.0001), overall International Prostate Symptom Score (IPSS) (p=0.0005), and IPSS QOL (p=0.02) were associated with SUI. On multivariate analysis, resected prostate weight was predictive of any SUI and tSUI, with no risk factors identified for long-term SUI. CONCLUSION: Post-HoLEP SUI occurs in ~10% of patients, with 1.5% continuing beyond six months. Most patients with tSUI recover within the first six weeks. Prostate size \u3e100g and catheter dependency are associated with increased risk tSUI. Larger prostate volume is an independent predictor of any SUI, and tSUI

Stability and Vibrational Analysis of a Flexible Damped Rotor System using Finite Element Method

Dynamic stability of a damped flexible Rotor system is studied in this work. Analysis of a damped rotating shaft with multiple discs are carried out by, varying the rotor offset positions in order to investigate the effect on critical speed and frequency of the system. From this analysis, it is observed that by varying the rotor offset positions, the modal mass participation varies and which in turn cause a variation in the critical speed and frequency of the system. This study also extends a detailed evaluation of damped rotor stability. Through this analysis it is observed that the system become unstable beyond its critical speed. The stabilizing effects of anisotropic bearing stiffness and external damping are also demonstrated. The effect of unbalance in the rotating machinery is evaluated in the last section

A Workflow-centric Study of Organizational Knowledge Distribution

Organizations require mechanisms to efficiently distribute knowledge such as news releases, seminar announcements, and memos. While the machinery for information storage, manipulation. and retrieval exists, research dealing directly with knowledge distribution in an organizational context is scarce. In this paper, we address this need by first examining the pros and cons of the conventional "mailing lists" approach and then proposing new workflow mechanisms that improve the efficiency and effectiveness of knowledge distribution. The main contributions of this study include: (I) a workflow perspective on organizational knowledge distribution. (2) workflow analysis of two new knowledge distribution methods based on dynamic mailing lists and profile matching, respectively, and (3) a new way of matching knowledge supply and demand that extends existing information filtering algorithms.Information Systems Working Papers Serie

Fe and N self-diffusion in non-magnetic Fe:N

Fe and N self-diffusion in non-magnetic FeN has been studied using neutron reflectivity. The isotope labelled multilayers, FeN/57Fe:N and Fe:N/Fe:15N were prepared using magnetron sputtering. It was remarkable to observe that N diffusion was slower compared to Fe while the atomic size of Fe is larger compared to N. An attempt has been made to understand the diffusion of Fe and N in non-magnetic Fe:N

Formation of iron nitride thin films with Al and Ti additives

In this work we investigate the process of iron nitride (Fe-N) phase formation using 2 at.% Al or 2 at.% Ti as additives. The samples were prepared with a magnetron sputtering technique using different amount of nitrogen during the deposition process. The nitrogen partial pressure (\pn) was varied between 0-50% (rest Argon) and the targets of pure Fe, [Fe+Ti] and [Fe+Al] were sputtered. The addition of small amount of Ti or Al results in improved soft-magnetic properties when sputtered using \pn $\leq$ 10\p. When \pn is increased to 50\p non-magnetic Fe-N phases are formed. We found that iron mononitride (FeN) phases (N at% $\sim$50) are formed with Al or Ti addition at \pn =50% whereas in absence of such addition \eFeN phases (N\pat$\sim$30) are formed. It was found that the overall nitrogen content can be increased significantly with Al or Ti additions. On the basis of obtained result we propose a mechanism describing formation of Fe-N phases Al and Ti additives.Comment: 9 Pages, 7 Figure

Deep Model Predictive Variable Impedance Control

The capability to adapt compliance by varying muscle stiffness is crucial for dexterous manipulation skills in humans. Incorporating compliance in robot motor control is crucial to performing real-world force interaction tasks with human-level dexterity. This work presents a Deep Model Predictive Variable Impedance Controller for compliant robotic manipulation which combines Variable Impedance Control with Model Predictive Control (MPC). A generalized Cartesian impedance model of a robot manipulator is learned using an exploration strategy maximizing the information gain. This model is used within an MPC framework to adapt the impedance parameters of a low-level variable impedance controller to achieve the desired compliance behavior for different manipulation tasks without any retraining or finetuning. The deep Model Predictive Variable Impedance Control approach is evaluated using a Franka Emika Panda robotic manipulator operating on different manipulation tasks in simulations and real experiments. The proposed approach was compared with model-free and model-based reinforcement approaches in variable impedance control for transferability between tasks and performance.Comment: Preprint submitted to the journal of robotics and autonomous system