Although some causes for malignant lymphoma are known their etiology is not well understood so far. We analyze the relationship between sun exposure and malignant lymphoma in a multicenter, population-based case-control study. Patients with malignant lymphoma (n = 710, 18-80 years) were prospectively recruited in 6 study regions in Germany. For each case, a gender, region and age-matched contro...

This paper is devoted to the study of an M/G/1 queue with a particular vacation discipline. The server is due to take a vacation as soon as it has served exactly N customers since the end of the previous vacation. N may be either a constant or a random variable. If the system becomes empty before the server has served N customers, then it stays idle until the next customer arrival. Such a vacat...

The paper presents two useful extensions of the incremental SVM in the context of online learning. An online support vector data description algorithm enables application of the online paradigm to unsupervised learning. Furthermore, online learning can be used in the large-scale classification problems to limit the memory requirements for storage of the kernel matrix. The proposed algorithms ar...

With millions of foreign tourists traveling the globe each year, tourism is regarded as largest and most significant industry in world. Mainstream operators with a large volume inexpensive affordable vacations dominate tour operations market. A specialty operator sector coexists mainstream market offers niche products to remain competitive. This study aims determine whether specialized Russian ...

In this paper we generalize known workload decomposition results for Lévy queues with secondary jump inputs and queues with server vacations or service interruptions. Special cases are polling systems with either compound Poisson or more general Lévy inputs. Our main tools are new martingale results, which have been derived in a companion paper.

Purpose This study aims to apply theory on consumer learning in virtual experiences compare how media technologies (i.e. reality [VR] and standard websites) users’ gender influence the ways which tourists gather pre-purchase information. Design/methodology/approach A laboratory experiment with fully immersive VR was conducted examine consumers’ behavior gathering The sample comprised 128 consum...