New Assessment Pack: - Screening and placement, diagnostic, and achievement (part and unit) tests. - Mid-term and final proficiency tests developed by Educational Testing Service. Centered on thematic instruction, the second edition of FOCUS ON GRAMMAR features: - Clear presentations and charts that make grammar easy to learn. - Creative activities that stimulate communication. - New high-interest readings, rich in content. - Review Tests to confirm progress and improve scores on standardized tests. - From Grammar to Writing section that builds composition skills. - New full-color pages that engage students in every activity. Start with the proven success of FOCUS ON GRAMMAR, and discover how easy it is to integrate grammar and communication skills.
Focus on Grammar – 3Ed High-Intermediate Course for Reference and Practice Student's Book
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Evaluating the GPRS Radio Interface for Different Quality of Service...
Figure 8 i ves iga es he impac of he maximum umber of GPRS user per cell o he performa ce of GPRS for he dy amic cha el alloca io scheme wi h 1 PDCH reserved. Of course, he expec ed umber of GPRS users should be less ha he maximum umber i order o avoid he rejec io of ew GPRS sessio s. O he o her ha d, he maximum umber of ac ive GPRS sessio s mus be limi ed for guara eei g quali y of service for every ac ive GPRS sessio eve u der high raffic. he radeoff be wee i creasi g performa ce for allowi g more ac ive GPRS sessio s a d he i creasi g blocki g probabili y for GPRS users is illus ra ed by he curves of Figure 8. Co clusio s his paper prese ed a discre e-eve simula or o he IP level for he Ge eral Packe Radio Service (GPRS). Wi h he simula or, we provided a comprehe sive performa ce s udy of he radio resource shari g by circui swi ched GSM co ec io s a d packe swi ched GPRS sessio s u der a s a ic a d a dy amic cha el alloca io scheme. I he dy amic scheme we assumed a reserved umber of physical cha els perma e ly alloca ed o GPRS a d he remai i g cha els o be o -dema d cha els ha ca be used by GSM voice service a d GPRS packe s.