Shape matching of two-dimensional objects

Journal ArticleIn this paper we present results in the areas of shape matching of nonoccluded and occluded two-dimensional objects. Shape matching is viewed as a "segment matching" problem. Unlike the previous work, the technique is based on a stochastic labeling procedure which explicitly maximizes a criterion function based on the ambiguity and inconsistency of classification. To reduce the computation time, the technique is hierarchical and uses results obtained at low levels to speed up and improve the accuracy of results at higher levels. This basic technique has been extended to the situation where various objects partially occlude each other to form an apparent object and our interest is to find all the objects participating in the occlusion. In such a case several hierarchical processes are executed in parallel for every object participating in the occlusion and are coordinated in such a way that the same segment of the apparent object is not matched to the segments of different actual objects. These techniques have been applied to two-dimensional simple closed curves represented by polygons and the power of the techniques is demonstrated by the examples taken from synthetic, aerial, industrial and biological images where the matching is done after using the actual segmentation methods

Segmentation of images having unimodal distributions

Journal ArticleA gradient relaxation method based on maximizing a criterion function is studied and compared to the nonlinear probabilistic relaxation method for the purpose of segmentation of images having unimodal distributions. Although both methods provide comparable segmentation results, the gradient method has the additional advantage of providing control over the relaxation process by choosing three parameters which can be tuned to obtain the desired segmentation results at a faster rate. Examples are given on two different types of scenes

Time-Optimal Control Studies for Additional Food provided Prey-Predator Systems involving Holling Type-III and Holling Type-IV Functional Responses

In recent years, time-optimal control studies on additional food provided prey-predator systems have gained significant attention from researchers in the field of mathematical biology. In this study, we initially consider an additional food provided prey-predator model exhibiting Holling type-III functional response and the intra-specific competition among predators. We prove the existence and uniqueness of global positive solutions for the proposed model. We do the time optimal control studies with respect quality and quantity of additional food as control variables by transforming the independent variable in the control system. Making use of the Pontraygin maximum principle, we characterize the optimal quality of additional food and optimal quantity of additional food. We show that the findings of these time-optimal control studies on additional food provided prey-predator systems involving Holling type III functional response have the potential to be applied to a variety of problems in pest management. In the later half of this study, we consider an additional food provided prey-predator model exhibiting Holling type-IV functional response and study the above aspects for this system

Stochastic Time-Optimal Control Studies for Additional Food provided Prey-Predator Systems involving Holling Type-IV Functional Response

We consider an additional food provided prey-predator model exhibiting Holling type IV functional response with combined continuous white noise and discontinuous L\'evy noise. We prove the existence and uniqueness of global positive solutions for the considered model. By considering the quality and quantity of additional food as control parameters, we formulate a time-optimal control problem. We obtain the condition for the existence of an optimal control. Furthermore, making use of the arrow condition of the sufficient stochastic maximum principle, we characterize the optimal quality of additional food and optimal quantity of additional food. Numerical results are given to illustrate the theoretical findings with applications in biological conservation and pest management

Stochastic Optimal and Time-Optimal Control Studies for Additional Food provided prey-predator Systems involving Holling Type-III Functional Response

This paper consists of a detailed and novel stochastic optimal control analysis of a coupled non-linear dynamical system. The state equations are modeled as additional food provided prey-predator system with Holling Type-III functional response for predator and intra-specific competition among predators. We firstly discuss the optimal control problem as a Lagrangian problem with a linear quadratic control. Secondly we consider an optimal control problem in the time-optimal control setting. Stochastic maximum principle is used for establishing the existence of optimal controls for both these problems. Numerical simulations are performed based on stochastic forward-backward sweep methods for realizing the theoretical findings. The results obtained in these optimal control problems are discussed in the context of biological conservation and pest management

Modeling and Sentiment Analysis of Online Reviews in Hospitality Industry

With the great extent of use of smartphones and the internet, the online hotel booking service providers have excessively increased thus producing more user-generated content in the form of reviews and comments about the customer experience. These reviews of visited customer’s aids hotel management personnel not only to forecast the future demand but also to implement effective strategies for better service. It is becoming a tuff job in this scenario for the hotel management to get exact information from the wide range of reviews. In this analysis, it is to identify the classification of the sentiment from the customer reviews. The classification can be done with text mining approach with the source of information. Two dictionaries are developed for the usage of data classification around 431 reviews taken from Tripadvisor.com and Booking.com. Finally Latent Dirichent Allocation (LDA) modeling algorithm is applied to identify related topics and it was used to sort out the issues in consumer sentiment analysis.     Study findings revealed that majority of the reviews were with positive sentiments and the topics found best with hospitality domain and sentiment term were such as “food”, “hospitality”, “room”, “people”, “friendly” , “Relax”, “feelings”, and “holiday” as hospitality terms and “Strong Positive” and “Ordinary Positive” as sentiment terms

Principles of Contract Design

Economic contract theory postulates two obstacles to complete contracts: high transaction costs and high enforcement (or verification) costs. The literature has proposed how parties might solve these problems under a stylized litigation system, but it does not address the question of how parties design contracts under the existing adversarial system, that relies on the parties to establish relevant facts indirectly by the use of evidentiary proxies. We advance a theory of contract design in a world of costly litigation. We examine the efficiency of investment at the front-end and back-end of the contracting process, where we focus on litigation as the back-end stage. In deciding whether to express their obligations in specific or vague terms, contracting parties implicitly choose their allocation of costs between the front- and back-end. When the parties agree to vague terms (or standards), such as best efforts or commercial reasonableness, they delegate to the back-end the task of selecting proxies: e.g., the court selects market indicators that serve as benchmarks for performance. When the parties agree to specific terms(or rules), they invest more at the front-end to specify proxies in their contract and thereby leaving a smaller task for the enforcing court. In this Article, we explore the choice between rules and standards in terms of this tradeoff, and offer an explanation for why contracts in practice have a mix of vague and specific provisions. We then suggest that parties can achieve further contracting gains by varying procedural rules governing the prospective enforcement of their disputes. We illustrate by examining provisions in commercial contracts that allocate burdens and standards of proof. If the parties can improve the cost-effectiveness of litigation in this manner, they can reduce back-end costs. They thereby create opportunities to further lower contracting costs (or to improve the incentive gains from contracting) by shifting more investment to the back-end by increasing their use of vague terms. Vague terms have fallen into disfavor with contract theorists and this Article offers a justification for why they are nevertheless commonplace in commercial practice. Our analysis highlights the general and valuable lesson that the anticipated path of litigation is relevant to contract design