This development provides a formalization of directed graphs, supporting (labelled) multi-edges and infinite graphs. A polymorphic edge type allows edges to be treated as pairs of vertices, if multi-edges are not required. Formalized properties are i.a. walks (and related concepts), connectedness and subgraphs and basic properties of isomorphisms. This formalization is used to prove characteriz...

In this paper a model is proposed for distribution centers location and joint replenishment of a distribution system that is responsible for orders and product delivery to distribution centers. This distribution centers are under limitedwarehouse space and this can determine amount of requirement product by considering proposed discount.The proposed model is develop to minimize total costs cons...

BACKGROUND The protoscoleces of fertile hydatid cysts are considered as major risks in surgery and producing secondary cysts if rupture the cyst during operation and, cause infecting the dogs with adult worm if eaten by this animal. Bacterial infection of the hydatid fluid can lead to sterilization of the cyst. OBJECTIVES The aim of this study was to determine the bacterial infection rate of ...

1. Introduction. This is a fascinating paper on an important topic: the choice of predictor variables in large-scale linear models. A previous paper in these pages attacked the same problem using the " LARS " algorithm (Efron, Hastie, Johnstone and Tibshirani [3]); actually three algorithms including the Lasso as middle case. There are tantalizing similarities between the Dantzig Selector (DS) ...

Provision of Social Goods and Soft Budget Constraints* by Lars-Hendrik Röller and Zhentang Zhang Firms in socialist and transitional economies are often obliged to provide a social good in addition to a private good, which makes it difficult for a government to commit not to bail out the firm once it is in financial trouble. This creates a soft budget constraint syndrome which causes the firm t...

the aim of this research was to measure the relative efficiency of forest management plans in north of iran. in order to fulfill the research, data of 12 forest management plans were collected from the financial balance sheets of shafaroud forest company during a ten years period. first of all, basic data envelopment analysis (dea) models (bcc and ccr) were used to determine the efficiency. the...

This is a multi-center retrospective study of patients underwent low anterior resection for rectal cancer. Ileostomy had been done to protect lying Colo-rectal anastomosis, closure ileostomy delayed in some due patient own will, surgical complications (anastomotic leak) or coarse chemotherapy. aimed find the effect temporary on post-operative bowel defunction which called Low syndrome (LARS), a...

LPH: As a graduate student at the University of Minnesota, I had the opportunity to take classes from Chris Sims and Tom Sargent. Both emphasized the idea that dynamic econometric models should be viewed as restrictions on stochastic processes. Sims’ classroom development of large sample econometrics broke with the more conventional view of the time of focusing on models with exogenous regresso...