On the chromatic roots of generalized theta graphs

The generalized theta graph \Theta_{s_1,...,s_k} consists of a pair of endvertices joined by k internally disjoint paths of lengths s_1,...,s_k \ge 1. We prove that the roots of the chromatic polynomial $pi(\Theta_{s_1,...,s_k},z) of a k-ary generalized theta graph all lie in the disc |z-1| \le [1 + o(1)] k/\log k, uniformly in the path lengths s_i. Moreover, we prove that \Theta_{2,...,2} \simeq K_{2,k} indeed has a chromatic root of modulus [1 + o(1)] k/\log k. Finally, for k \le 8 we prove that the generalized theta graph with a chromatic root that maximizes |z-1| is the one with all path lengths equal to 2; we conjecture that this holds for all k.Comment: LaTex2e, 25 pages including 2 figure

Visoko obrazovanje, nezaposlenost i stanje na tržištu rada

Uticaj obrazovanja na strukturne performanse tržišta rada sve je izraženiji. Pitanje međuzavisnosti visokog obrazovanja i kretanja na tržištu rada postaje posebno relevantno u uslovima rastuće nezaposlenosti sa kojom se suočavaju tranzicione ali sve više i razvijene zemlje sveta. Rezultati istraživanja ukazuju da u razvijenim tržišnim ekonomijama visokoobrazovani imaju mnogo manje šanse da budu nezaposleni, kao i veće mogućnosti da traže i pronađu posao sa boljom zaradom i boljim uslovima rada, od čega koristi imaju i pojedinac i država. U strukturi nezaposlenih lica u Srbiji dominiraju radnici sa nižom stručnom spremom koje je i najteže ponovo zaposliti, a prema procentu visokoobrazovanog stanovništva Srbija je u zaostatku ne samo za prosekom EU već i za zemljama u regionu. Imajući u vidu da obrazovanje doprinosi kvalitetu radne snage, inovacijama, istraživanju i otvaranju novih radnih mesta, Srbija, u kojoj je svega 6,5% fakultetski obrazovanih građana, se nalazi pred velikim izazovom i teško da će u godinama koje dolaze svoj rast i razvoj zasnivati na ekonomiji znanja. Pored analize stanja na tržištu rada Srbije i poređenja odnosa između stepena obrazovanja i stope nezaposlenosti u zemljama EU i Srbiji, cilj istraživanja u okviru ovog rada je i davanje sugestija kreatorima ekonomske politike u pogledu povećanja procenta visokoobrazovanih, kao preduslova smanjenja stope nezaposlenosti

Finansiranje kao jedna od ključnih prepreka razvoju malih i srednjih preduzeća u Srbiji

Problematično finansiranje predstavlja jednu od najvećih prepreka razvoju malih i srednjih preduzeća (MSP). Osnivanje preduzeća, širenje poslovnih aktivnosti, razvoj novih proizvoda i investicije u postrojenja, opremu i ljudske resurse determinisani su mogućnostima finansiranja iz povoljnih izvora. Otežano finansiranje MSP je posledica ograničenosti sopstvenih sredstava sa jedne strane i manje dostupnosti sredstava iz pozajmljenih izvora sa druge strane. Predmet istraživanja su izvori i problemi finansiranja MSP u Srbiji. Cilj rada je da se na osnovu rezultata terenskog istraživanja pod nazivom: "Finansiranje MSP u Srbiji" (koje je sprovedeno u okviru projekta "Izazovi i perspektive strukturnih promena u Srbiji: strateški pravci ekonomskog razvoja i usklađivanje sa zahtevima EU) analiziraju ključni aspekti problematike finansiranja MSP u Srbiji i predlože moguća rešenja

Marine associated bird and mammal habitat use at the Five Finger Lighthouse Island

Master's Project (M.N.R.M.) University of Alaska Fairbanks, 2018.In summer 2017 I studied the abundance and distribution of marine associated birds and mammals from four observational points on the southernmost of the Five Finger Islands (FFI). My objectives were (1) to identify the areas of highest habitat use by species of conservation concern, and (2) to use this information to make recommendations for an ecosystem-based management plan at the Five Finger Lighthouse Island (FFLI). I found higher relative abundance and higher biodiversity of both birds and marine mammals on the South and West facing sectors compared to the North and East facing sectors. I attribute this to the greater habitat complexity that comprises a near-shore reef, a mixed kelp forest, and a channel between the reef and the side of the island with the highest cliff, areas used extensively for foraging, nesting, traveling, socializing, and resting by many of the documented species. I therefore recommend avoiding development and minimizing anthropogenic disturbance on the southern and western portions of the island including the adjacent reef and channel between the reef and island. As both the FFI ecosystem and the Five Finger Lighthouse (FFL) management continue to evolve in response to changing environmental conditions and human needs, this study provides a useful baseline for future comparison. Continued study and monitoring is also recommended at this site to inform future adaptive management, document changes over time, and engage community stakeholders in science and conservation

On rational approximation of algebraic functions

We construct a new scheme of approximation of any multivalued algebraic function $f(z)$ by a sequence $\{r_{n}(z)\}_{n\in \mathbb{N}}$ of rational functions. The latter sequence is generated by a recurrence relation which is completely determined by the algebraic equation satisfied by $f(z)$. Compared to the usual Pad\'e approximation our scheme has a number of advantages, such as simple computational procedures that allow us to prove natural analogs of the Pad\'e Conjecture and Nuttall's Conjecture for the sequence $\{r_{n}(z)\}_{n\in \mathbb{N}}$ in the complement \mathbb{CP}^1\setminus \D_{f}, where \D_{f} is the union of a finite number of segments of real algebraic curves and finitely many isolated points. In particular, our construction makes it possible to control the behavior of spurious poles and to describe the asymptotic ratio distribution of the family $\{r_{n}(z)\}_{n\in \mathbb{N}}$. As an application we settle the so-called 3-conjecture of Egecioglu {\em et al} dealing with a 4-term recursion related to a polynomial Riemann Hypothesis.Comment: 25 pages, 8 figures, LaTeX2e, revised version to appear in Advances in Mathematic

Innovative activities of small and medium-sized enterprises in Serbia

Small and medium-sized enterprises are the backbone of innovation in developed economies. In transitional countries small and medium-sized enterprises are becoming increasingly important for economic growth and development but are significantly lagging behind in terms of their propensity to innovate. The main objective of the paper is to perceive the attitude of Serbian small and medium-sized enterprises towards innovative activities in order to determine the type, the scope and the quality of these activities. This paper also aims at analyzing institutional support for enhancing SME innovation in Serbia. A set of recommendations for strengthening the capacity of small and medium-sized enterprises for innovative activities is provided. Furthermore, few possibilities for removing the main barriers to small and medium-sized enterprises’ wider use of innovation and research are discussed in the paper

Transform-scaled process priors for trait allocations in Bayesian nonparametrics

Completely random measures (CRMs) provide a broad class of priors, arguably, the most popular, for Bayesian nonparametric (BNP) analysis of trait allocations. As a peculiar property, CRM priors lead to predictive distributions that share the following common structure: for fixed prior's parameters, a new data point exhibits a Poisson (random) number of ``new'' traits, i.e., not appearing in the sample, which depends on the sampling information only through the sample size. While the Poisson posterior distribution is appealing for analytical tractability and ease of interpretation, its independence from the sampling information is a critical drawback, as it makes the posterior distribution of ``new'' traits completely determined by the estimation of the unknown prior's parameters. In this paper, we introduce the class of transform-scaled process (T-SP) priors as a tool to enrich the posterior distribution of ``new'' traits arising from CRM priors, while maintaining the same analytical tractability and ease of interpretation. In particular, we present a framework for posterior analysis of trait allocations under T-SP priors, showing that Stable T-SP priors, i.e., T-SP priors built from Stable CRMs, lead to predictive distributions such that, for fixed prior's parameters, a new data point displays a negative-Binomial (random) number of ``new'' traits, which depends on the sampling information through the number of distinct traits and the sample size. Then, by relying on a hierarchical version of T-SP priors, we extend our analysis to the more general setting of trait allocations with multiple groups of data or subpopulations. The empirical effectiveness of our methods is demonstrated through numerical experiments and applications to real data

Evaluation of transition process by using selected macroeconomic indicators and recommendations for more advanced economic growth

The main objective of the paper is to evaluate the effects of transition on economic trends in the Western Balkan (WB) countries by using the selected economic indicators and to elicit recommendations for more advanced economic growth. The economic trends in the WB countries in the last two decades are characterized by unsatisfactory level of actual gross domestic product, high unemployment and foreign trade deficits, insufficient foreign direct investments and growing indebtedness. Given that the above economic trends are caused by different political and economic circumstances as well as dynamics and the way they implemented a comprehensive economic reform in order to shift from a centrally planned to a market based economy and integrate into the EU, the paper reviews the basic characteristics of the transition in the WB countries and evaluates their effects on the level of economic development of each country

The role of development entrepreneurship and small and medium enterprises in managing structural changes

Small and medium-sized enterprises, under the direction of entrepreneurs, are considered to be the driving force of economic growth and development. Entrepreneurship is associated with job creation, innovation, welfare distribution, poverty reduction and an increase in economic performances of a country. In the last decade, there has been an increasing recognition of the role of entrepreneurs in economic development of Serbia. The main objective of the chapter is to analyse development of entrepreneurship and its contribution to economic development of Serbia over the 2006-2010 period of time by using the methodology initially developed by Venesaar and Loomets (2006), and adjusted to the objectives of this study and to the available data. The methodology assesses the development of entrepreneurship through SMEE sector development and new firm formation activity over the observed period. The measured firm formation rate indicated relatively strong but insufficient intensity of entrepreneurial activity. The empirical analysis shows a relatively stable activity in firm formation over time in terms of the average annual number of registrations per 1,000 active inhabitants and more significant variations in terms of the ratio of new firm registrations to the registered stock of businesses at the end of the year. The data also show a positive and significant relationship between firm formation rate and employment generation as an important indicator of economic development