The purpose of this thesis is to explore the concept of resource scheduling and pricing and its relation to carrier aggregation. The first main topic is a modified Frank Kelly algorithm that allows for the use of utility functions that are piecewise concave, but not a member of a strictly \'diminishing return\' model. This adjustment to the Frank Kelly algorithm allows resource allocation to take into account devices with multiple applications. The second topic introduces the idea of scheduling resources in a carrier aggregation scenario assuming the carriers are scheduled sequentially. / Master of Science

"This thesis describes the development of an optimized software-defined-radio implementation of a distributed beamforming system and presents experimental results for two-source and three- source wired-channel and acoustic-channel distributed beamforming using the time-slotted round-trip carrier synchronization protocol. The frequency and phase synthesizer used in this system is based on an optimized ``hybrid' phase locked loop (PLL) with averaging window which is shown to have high frequency estimation accuracy and consistency. For the wired-channel experiments, each source node was implemented by a TMS320C6713DSK while for the acoustic experiments, each source node in the system was built using commercial off-the-shelf parts including TMS320C6713DSK, microphone, speaker, audio amplifier, and battery. The source node functionality including phase locked loops and the logic associated with the time-slotted round-trip carrier synchronization protocol was realized through real-time software independently running on each source node's C6713 digital signal processor. Experimental results for two-source and three-source realizations of the wired-channel and acoustic-channel distributed beamforming system are presented. The results show that near-ideal beamforming performance can be consistently achieved at acoustic wavelengths equivalent to common radio frequency wavelengths."

Em bovinos de corte, maiores diâmetros do folículo pré-ovulatório (FPO) e as subsequentes altas concentrações de progesterona [P4] aumentam o crescimento do concepto e a taxa de prenhez. Formulou-se a hipótese que a modulação do tamanho do FPO e [P4] no diestro subsequente à ovulação do FPO estimulam a expressão endometrial de transcritos e proteínas da famílias das Solute Carrier Proteins (SLC) que estão relacionadas ao transporte de glicose. Vacas Nelore (n=60), solteiras e ciclando receberam duas injeções de PGF2&alpha; (PGF; 0,5mg; i.m.) com intervalo de 14 dias. Dez dias após (dia -10; D-10), receberam um dispositivo intravaginal liberador de P4 e benzoato de estradiol (2mg; i.m.). Para modular o crescimento do FPO e alterar a produção de P4 pós-ovulação, no D-10 os animais receberam PGF (grupo alta P4; AP) ou não (grupo baixa P4; BP). Dispositivos foram removidos e PGF injetada 60 a 42 horas antes da indução da ovulação para o grupo AP e 48 a 30 horas antes da indução para o grupo BP e ovulações foram induzidas com GnRH (buserelina; 10&micro;g; i.m.) no D0. Crescimento e ovulação do FPO e formação do CL foram avaliados por ultrassom e [P4] medidas por radioimunoensaio. No D7 os animais que ovularam foram abatidos (AP, N=18 e BP, N=18), o endométrio foi dissecado e submetido à extração de RNA total para análises de qPCR, extração de proteínas totais para análises de western blotting e incluído em parafina para análises de imunohistoquímica. Diferença entre as médias dos grupos foi determinada pelo teste t de student. O diâmetro máximo do FPO (média ± erro padrão da média; 12,8±0,4 vs. 11,1±0,4mm) foi maior no grupo AP (P<0,01). A [P4] no D7 foi maior no grupo AP (4,5±1,0 ng/mL vs. 3,3±1,1 ng/mL; P<0,05). As concentrações relativas dos transcritos que codificam SLCs foram determinadas por qPCR, usando a ciclofilina como controle endógeno. Não houve diferença na expressão de SLC2A1 (0,91±0,04 vs. 1,02±0,07), SLC2A3 (1,14±0,16 vs. 1,05±0,1), SLC2A4 (1,20±0,14 vs. 1,01±0,05), SLC2A5 (0,95±0,12 vs. 1,04±0,12), SLC5A1 (1,35±0,25 vs. 1,49±0,44), ATP1A2 (1,29±0,17 vs. 1,03±0,1), ATP1B2 (1,20±0,11 vs. 1,06±0,1), SLC37A4 (1,16±0,16 vs. 1,1±0,12), entre os grupos AP e BP respectivamente (P>0.05). Também não foi possível identificar diferença na quantidade proteica de SLC2A1 no endométrio dos animais do grupo AP em relação ao grupo BP. SLC2A1 foi identificada na membrana basal no epitélio luminal (EL), epitélio glandular (EG) e no estroma uterino dos animais. SLC2A4 foi identificada na membrana basal e membrana apical no EL, EG e no estroma uterino dos animais. Em conclusão, a modulação do tamanho do FPO e [P4] no diestro não afetaram a expressão gênica ou proteica dos transportadores de glicose. É possível que ao invés da expressão gênica ou proteica, a atividade transportadora das SLCs, ou ainda, a expressão e função de genes relacionados ao metabolismo de carboidratos, sejam regulados pelo ambiente endócrino peri-ovulatório em vacas. / In beef cattle, changes in the peri-ovulatory endocrine milieu are associated with conceptus growth and fertility. A large size of the pre-ovulatory follicle (POF) and resulting elevated progesterone (P4) concentrations during diestrus affect pregnancy rates positively. Our hypothesis is that modulation of POF size and diestrus P4 concentrations regulate nutrient availability in the uterus. Specifically, optimal glucose concentrations in the histotroph are required for adequate embryo growth during early gestation. The objective was to determine if POF size and resulting P4 concentrations during the first week of diestrus influence gene expression of Solute Carrier Protein (SLC) families that are related to glucose transport. Cyclic, non-lactating Nelore cows received two injections of cloprostenol (PGF; 0.5mg; i.m.) 14 days apart. Ten days later (day -10; D-10), cows received a P4-releasing device along with estradiol benzoate (2mg; i.m.). To modulate the growth of the POF and alter post-ovulatory P4 production, on D-10 animals received PGF (high post-ovulatory P4 group; HP) or not (low post-ovulatory P4 group; LP). The P4-releasing devices were removed and PGF injected 60 to 42 hours before the ovulation induction in the HP group and 48 to 30 hours before the ovulation induction in the LP group. Ovulation was induced with buserelin (GnRH; 10&micro;g; i.m.) on D0. Diameter of POF and ovulation were assessed by ultrasonography starting onD- 2. From D1 to D7, plasma was obtained for measurement of P4 concentration. On D7, cows that ovulated were slaughtered (HP, n=18 and LP, n=18) and endometrium was dissected and subjected total RNA extraction for qPCR analyzes, total protein extraction for western blotting analyzes and included in paraffin for imunohistochemical analyzes. Differences between group means were determined by student\'s t test. Maximum diameter of the POF (mean ± SEM; 12.8±0.4 vs. 11.1±0.4mm) was greater in HP vs. LP (P<0.01). Progesterone concentration on D7 was larger on the HP group (4.5±1.0 ng/mL and 3.3±1.1 ng/mL; P<0.05). Relative concentrations of transcripts coding for facilitative sugar transporters (SLC2A1, SLC2A3, SLC2A4 and SLC2A5), a sodium-dependent glucose co-transporter (SLC5A1) and other transporters related to glucose uptake (ATP1A2, ATP1B2, SLC37A4) were determined by qPCR, using cyclophilin as the endogenous control gene. There were no significant differences in expression of SLC2A1 (mean ± SEM;0.91±0.04 vs. 1.02±0.07), SLC2A3 (1.14±0.16 vs. 1.05±0.1), SLC2A4 (1.20±0.14 vs. 1.01±0.05), SLC2A5 (0.95±0.12 vs. 1.04±0.12), SLC5A1 (1.35±0.25 vs. 1.49±0.44), ATP1A2 (1.29±0.17 vs. 1.03±0.1), ATP1B2 (1.20±0.11 VS. 1.06±0.1) ,SLC37A4 (1.16±0.16 vs. 1.1±0.12), between HP and LP, respectively (P>0.05). There was no difference in the abundance of SLC2A1 protein between groups. The SLC2A1 protein was localized in the luminal epithelium (LE), glandular epithelium (GE) and uterine stroma (US) of animals. The SLC2A4 protein was localized on the basal and apical membrane of the LE, GE and US of animals. In conclusion, modulation of POF size and diestrus P4 concentrations did not affect the expression of glucose transporter genes or proteins. It is possible that activity of SLC proteins rather than gene expression, or alternatively, expression and function of genes related to carbohydrate metabolism, are regulated by the peri-ovulatory endocrine milieu in cows.

Array-CGH analysis of the gastric cancer cell lines suggested that TXNIP loci were intact, suggesting that allelic loss might not be the major mechanism responsible for the downregulation of TXNIP in these cells. Furthermore, our data suggested that promoter hypermethylation of TXNIP may not be an important epigenetic mechanism that regulate the silencing of this gene. Chromatin immunoprecipitation (ChIP) assay revealed that SAHA induced hyperacetylation of histone H3 and H4 at the 5' flanking region of TXNIP gene, suggesting SAHA could promote TXNIP gene transcription via modification of histones located at the promoter region. Our data revealed that the loss or reduced expression of TXNIP in gastric cancer cells is associated with epigenetic histone acetylation mechanism. / Gastric cancer is a common cancer especially in Asian countries and is associated with high morbidity and mortality. Epigenetic inactivation of tumor suppressor is a common mechanism involved in carcinogenesis of a variety of human cancers and recent evidence suggested that targeting epigenetic modifications may be an approach to combat cancer. Our group and others have demonstrated frequent promoter methylation of cancer related genes in gastric cancer. In this study, we aim to identify cancer associated genes regulated by another important epigenetic mechanism, namely histone acetylation. / In addition, we demonstrated that over-expression of TXNIP significantly reduced cell migration ability and inhibited cell invasiveness in gastric cancer cells. Furthermore, absence or reduced expression of TXNIP in gastric cancer was associated with diffuse-type gastric cancer, advanced stage disease and predicted a poor disease specific survival. The findings supported that TXNIP is a functional tumor suppressor gene and may be a potential biomarker in gastric cancer. / We analyzed 25 paired gastric cancer and non-cancer gastric mucosa and found that expression of TXNIP mRNA level was reduced in 84% of gastric cancer and was significantly downregulated as compared to the paired non-cancer gastric tissues (p=0.002). Expression of TXNIP protein by western blot was down-regulated in 3 out of 5 cases. Furthermore, by immunohistochemical staining of TXNIP in tissue array containing 150 cases of gastric cancer also showed frequent down-regulation of TXNIP expression and &sim;26% with complete lack of TXNIP expression. / We first showed that suberoylanilide hydroxamic acid (SAHA), a well known histone deacetylase inhibitor, has anti-proliferative effect in a panel of gastric cancer cell lines (MKN1, MKN7, MKN28, MKN45, SNU1, SNU16, AGS, N87 and KatoIII cells). We compared gene expression profiles of SAHA treated vs control AGS cells to identify a set of genes that were differentially upregulated by SAHA treatment. Based on our microarray analysis in nine gastric cancer cell lines (MKN1, MKN7, MKN28, MKN45, SNU1, SNU16, AGS, N87 and KatoIII) and normal gastric tissues, a set of commonly downregulated genes in gastric cancer cells was elucidated. Analysis of these data sets with subsequent confirmation using real-time PCR analysis, genes that were downregulated in gastric cancer cells but upregulated upon SAHA treatment were identified. Among these selected genes, Thioredoxin Interacting Protein (also known as VDUP-1/TBP2/TXNIP ) was down-regulated in all cancer cell lines tested, and its protein expression was significantly induced by SAHA treatment in a numbers of gastric cancer cell lines including AGS, MKN1, MKN45, N87 and KatoIII. Thus, we focused on the TXNIP in the subsequent studies. / Tang, Angie. / Adviser: To Ka Fai. / Source: Dissertation Abstracts International, Volume: 72-04, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 180-202). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Em bovinos de corte, maiores diâmetros do folículo pré-ovulatório (FPO) e as subsequentes altas concentrações de progesterona [P4] aumentam o crescimento do concepto e a taxa de prenhez. Formulou-se a hipótese que a modulação do tamanho do FPO e [P4] no diestro subsequente à ovulação do FPO estimulam a expressão endometrial de transcritos e proteínas da famílias das Solute Carrier Proteins (SLC) que estão relacionadas ao transporte de glicose. Vacas Nelore (n=60), solteiras e ciclando receberam duas injeções de PGF2&alpha; (PGF; 0,5mg; i.m.) com intervalo de 14 dias. Dez dias após (dia -10; D-10), receberam um dispositivo intravaginal liberador de P4 e benzoato de estradiol (2mg; i.m.). Para modular o crescimento do FPO e alterar a produção de P4 pós-ovulação, no D-10 os animais receberam PGF (grupo alta P4; AP) ou não (grupo baixa P4; BP). Dispositivos foram removidos e PGF injetada 60 a 42 horas antes da indução da ovulação para o grupo AP e 48 a 30 horas antes da indução para o grupo BP e ovulações foram induzidas com GnRH (buserelina; 10&micro;g; i.m.) no D0. Crescimento e ovulação do FPO e formação do CL foram avaliados por ultrassom e [P4] medidas por radioimunoensaio. No D7 os animais que ovularam foram abatidos (AP, N=18 e BP, N=18), o endométrio foi dissecado e submetido à extração de RNA total para análises de qPCR, extração de proteínas totais para análises de western blotting e incluído em parafina para análises de imunohistoquímica. Diferença entre as médias dos grupos foi determinada pelo teste t de student. O diâmetro máximo do FPO (média ± erro padrão da média; 12,8±0,4 vs. 11,1±0,4mm) foi maior no grupo AP (P<0,01). A [P4] no D7 foi maior no grupo AP (4,5±1,0 ng/mL vs. 3,3±1,1 ng/mL; P<0,05). As concentrações relativas dos transcritos que codificam SLCs foram determinadas por qPCR, usando a ciclofilina como controle endógeno. Não houve diferença na expressão de SLC2A1 (0,91±0,04 vs. 1,02±0,07), SLC2A3 (1,14±0,16 vs. 1,05±0,1), SLC2A4 (1,20±0,14 vs. 1,01±0,05), SLC2A5 (0,95±0,12 vs. 1,04±0,12), SLC5A1 (1,35±0,25 vs. 1,49±0,44), ATP1A2 (1,29±0,17 vs. 1,03±0,1), ATP1B2 (1,20±0,11 vs. 1,06±0,1), SLC37A4 (1,16±0,16 vs. 1,1±0,12), entre os grupos AP e BP respectivamente (P>0.05). Também não foi possível identificar diferença na quantidade proteica de SLC2A1 no endométrio dos animais do grupo AP em relação ao grupo BP. SLC2A1 foi identificada na membrana basal no epitélio luminal (EL), epitélio glandular (EG) e no estroma uterino dos animais. SLC2A4 foi identificada na membrana basal e membrana apical no EL, EG e no estroma uterino dos animais. Em conclusão, a modulação do tamanho do FPO e [P4] no diestro não afetaram a expressão gênica ou proteica dos transportadores de glicose. É possível que ao invés da expressão gênica ou proteica, a atividade transportadora das SLCs, ou ainda, a expressão e função de genes relacionados ao metabolismo de carboidratos, sejam regulados pelo ambiente endócrino peri-ovulatório em vacas. / In beef cattle, changes in the peri-ovulatory endocrine milieu are associated with conceptus growth and fertility. A large size of the pre-ovulatory follicle (POF) and resulting elevated progesterone (P4) concentrations during diestrus affect pregnancy rates positively. Our hypothesis is that modulation of POF size and diestrus P4 concentrations regulate nutrient availability in the uterus. Specifically, optimal glucose concentrations in the histotroph are required for adequate embryo growth during early gestation. The objective was to determine if POF size and resulting P4 concentrations during the first week of diestrus influence gene expression of Solute Carrier Protein (SLC) families that are related to glucose transport. Cyclic, non-lactating Nelore cows received two injections of cloprostenol (PGF; 0.5mg; i.m.) 14 days apart. Ten days later (day -10; D-10), cows received a P4-releasing device along with estradiol benzoate (2mg; i.m.). To modulate the growth of the POF and alter post-ovulatory P4 production, on D-10 animals received PGF (high post-ovulatory P4 group; HP) or not (low post-ovulatory P4 group; LP). The P4-releasing devices were removed and PGF injected 60 to 42 hours before the ovulation induction in the HP group and 48 to 30 hours before the ovulation induction in the LP group. Ovulation was induced with buserelin (GnRH; 10&micro;g; i.m.) on D0. Diameter of POF and ovulation were assessed by ultrasonography starting onD- 2. From D1 to D7, plasma was obtained for measurement of P4 concentration. On D7, cows that ovulated were slaughtered (HP, n=18 and LP, n=18) and endometrium was dissected and subjected total RNA extraction for qPCR analyzes, total protein extraction for western blotting analyzes and included in paraffin for imunohistochemical analyzes. Differences between group means were determined by student\'s t test. Maximum diameter of the POF (mean ± SEM; 12.8±0.4 vs. 11.1±0.4mm) was greater in HP vs. LP (P<0.01). Progesterone concentration on D7 was larger on the HP group (4.5±1.0 ng/mL and 3.3±1.1 ng/mL; P<0.05). Relative concentrations of transcripts coding for facilitative sugar transporters (SLC2A1, SLC2A3, SLC2A4 and SLC2A5), a sodium-dependent glucose co-transporter (SLC5A1) and other transporters related to glucose uptake (ATP1A2, ATP1B2, SLC37A4) were determined by qPCR, using cyclophilin as the endogenous control gene. There were no significant differences in expression of SLC2A1 (mean ± SEM;0.91±0.04 vs. 1.02±0.07), SLC2A3 (1.14±0.16 vs. 1.05±0.1), SLC2A4 (1.20±0.14 vs. 1.01±0.05), SLC2A5 (0.95±0.12 vs. 1.04±0.12), SLC5A1 (1.35±0.25 vs. 1.49±0.44), ATP1A2 (1.29±0.17 vs. 1.03±0.1), ATP1B2 (1.20±0.11 VS. 1.06±0.1) ,SLC37A4 (1.16±0.16 vs. 1.1±0.12), between HP and LP, respectively (P>0.05). There was no difference in the abundance of SLC2A1 protein between groups. The SLC2A1 protein was localized in the luminal epithelium (LE), glandular epithelium (GE) and uterine stroma (US) of animals. The SLC2A4 protein was localized on the basal and apical membrane of the LE, GE and US of animals. In conclusion, modulation of POF size and diestrus P4 concentrations did not affect the expression of glucose transporter genes or proteins. It is possible that activity of SLC proteins rather than gene expression, or alternatively, expression and function of genes related to carbohydrate metabolism, are regulated by the peri-ovulatory endocrine milieu in cows.

Wireless communication systems such as multipoint communication systems (MCS) are becoming attractive as cost-effective means for providing network access in sparsely populated, rugged, or developing areas of the world. Since the radio spectrum is limited, it is desirable to use spectrally efficient modulation methods such as quadrature amplitude modulation (QAM) for high data rate channels. Many MCS employ time division multiple access (TDMA) and/or time division duplexing (TDD) techniques, in which transmissions operate in bursts. In many cases, a preamble of known symbols is appended to the beginning of each burst for carrier and symbol timing recovery (symbol timing is assumed known in this thesis). Preamble symbols consume bandwidth and power and are not used to convey information. In order for burst-mode communications to provide efficient data throughput, the synchronization time must be short compared to the user data portion of the burst. <p> Traditional methods of communication system synchronization such as phase-locked loops (PLLs) have demonstrated reduced performance when operated in burst-mode systems. In this thesis, a feedforward (FF) digital carrier recovery technique to achieve rapid carrier synchronization is proposed. The estimation algorithms for determining carrier offsets in carrier acquisition and tracking in a linear channel environment corrupted by additive white Gaussian noise (AWGN) are described. The estimation algorithms are derived based on the theory of maximum likelihood (ML) parameter estimation. The estimations include data-aided (DA) carrier frequency and phase estimations in acquisition and non-data-aided (NDA) carrier phase estimation in tracking. The DA carrier frequency and phase estimation algorithms are based on oversampling of a known preamble. The NDA carrier phase estimation makes use of symbol timing knowledge and estimates are extracted from the random data portion of the burst. The algorithms have been simulated and tested using Matlab® to verify their functionalities. The performance of these estimators is also evaluated in the burst-mode operations for 16-QAM and compared in the presence of non-ideal conditions (frequency offset, phase offset, and AWGN). The simulation results show that the carrier recovery techniques presented in this thesis proved to be applicable to the modulation schemes of 16-QAM. The simulations demonstrate that the techniques provide a fast carrier acquisition using a short preamble (about 111 symbols) and are suitable for burst-mode communication systems.

Wireless communication systems such as multipoint communication systems (MCS) are becoming attractive as cost-effective means for providing network access in sparsely populated, rugged, or developing areas of the world. Since the radio spectrum is limited, it is desirable to use spectrally efficient modulation methods such as quadrature amplitude modulation (QAM) for high data rate channels. Many MCS employ time division multiple access (TDMA) and/or time division duplexing (TDD) techniques, in which transmissions operate in bursts. In many cases, a preamble of known symbols is appended to the beginning of each burst for carrier and symbol timing recovery (symbol timing is assumed known in this thesis). Preamble symbols consume bandwidth and power and are not used to convey information. In order for burst-mode communications to provide efficient data throughput, the synchronization time must be short compared to the user data portion of the burst. <p> Traditional methods of communication system synchronization such as phase-locked loops (PLLs) have demonstrated reduced performance when operated in burst-mode systems. In this thesis, a feedforward (FF) digital carrier recovery technique to achieve rapid carrier synchronization is proposed. The estimation algorithms for determining carrier offsets in carrier acquisition and tracking in a linear channel environment corrupted by additive white Gaussian noise (AWGN) are described. The estimation algorithms are derived based on the theory of maximum likelihood (ML) parameter estimation. The estimations include data-aided (DA) carrier frequency and phase estimations in acquisition and non-data-aided (NDA) carrier phase estimation in tracking. The DA carrier frequency and phase estimation algorithms are based on oversampling of a known preamble. The NDA carrier phase estimation makes use of symbol timing knowledge and estimates are extracted from the random data portion of the burst. The algorithms have been simulated and tested using Matlab® to verify their functionalities. The performance of these estimators is also evaluated in the burst-mode operations for 16-QAM and compared in the presence of non-ideal conditions (frequency offset, phase offset, and AWGN). The simulation results show that the carrier recovery techniques presented in this thesis proved to be applicable to the modulation schemes of 16-QAM. The simulations demonstrate that the techniques provide a fast carrier acquisition using a short preamble (about 111 symbols) and are suitable for burst-mode communication systems.

In this dissertation, the problem of symbol timing synchronization for the following three different communication systems is studied: 1) conventional single-carrier transmissions with single antenna in both transmitter and receiver; 2) single-carrier transmissions with multiple antennas at both transmitter and receiver; and 3) orthogonal frequency division multiplexing (OFDM) based IEEE 802.11a wireless local area networks (WLANs). For conventional single-carrier, single-antenna systems, a general feedforward symbol-timing estimation framework is developed based on the conditional maximum likelihood principle. The proposed algorithm is applied to linear modulations and two commonly used continuous phase modulations: MSK and GMSK. The performance of the proposed estimator is analyzed analytically and via simulations. Moreover, using the newly developed general estimation framework, all the previously proposed digital blind feedforward symbol timing estimators employing second-order statistics are cast into a unified framework. The finite sample mean-square error expression for this class of estimators is established and the best estimators are determined. Simulation results are presented to corroborate the analytical results. Moving on to single-carrier, multiple-antenna systems, we present two algorithms. The first algorithm is based on a heuristic argument and it improves the optimum sample selection algorithm by Naguib et al. so that accurate timing estimates can be obtained even if the oversampling ratio is small. The performance of the proposed algorithm is analyzed both analytically and via simulations. The second algorithm is based on the maximum likelihood principle. The data aided (DA) and non-data aided (NDA) ML symbol timing estimators and their cor- responding CCRB and MCRB in MIMO correlated ??at-fading channels are derived. It is shown that the improved algorithm developed based on the heuristic argument is just a special case of the DA ML estimator. Simulation results under different operating conditions are given to assess and compare the performances of the DA and NDA ML estimators with respect to their corresponding CCRBs and MCRBs. In the last part of this dissertation, the ML timing synchronizer for IEEE 802.11a WLANs on frequency-selective fading channels is developed. The proposed algorithm is compared with four of the most representative timing synchronization algorithms, one specically designed for IEEE 802.11a WLANs and three other algorithms designed for general OFDM frame synchronization.

Magistro darbe suformuluota problema, jog šiuo metu Lietuvoje nepakankamai dėmesio skiriama ikimokyklinio ugdymo pedagogų karjeros sampratai bei veiksniams, darantiems įtaką pedagogų karjeros raidai. Išanalizuoti ir susisteminti įvairių Lietuvos ir užsienio autorių teoriniai ir praktiniai darbai karjeros klausimais leidžia teigti, jog motyvacija yra svarbiausia ikimokyklinio ugdymo pedagogų karjeros prielaida, kuri yra stimuliuojama objektyvių (išorinių) ir subjektyvių (vidinių) veiksnių sąveikos. Darbe siekiama įvertinti veiksnius, įtakojančius ikimokyklinio ugdymo pedagogų karjerą. Tyrimo rezultatai parodė, jog dabartinė pedagogų kvalifikacijos kėlimo sistema gali būti kliūtimi ikimokyklinio ugdymo pedagogų karjeros procese. Dominuojančia pedagogų karjeros orientacija yra techninė/funkcinė kompetencija. Pedagogai sutinka, jog darbas darželyje gali būti sietinas su karjera, visgi tik maža dalis pedagogų mano, jog jų karjera yra sėkminga. Šiame darbe pateiktos rekomendacijos bus panaudotos tiriamų įstaigų kaitai, pedagogų motyvavimui karjerai bei trūkstamų pedagogų kompetencijų išaiškinimui. 2009 m. balandžio 23 d. ir 2010 balandžio 22 d. autorė dalyvavo studentų mokslinių darbų konferencijose ,,Ekonomikos ir vadybos aktualijos‘‘ ŠU Socialinių mokslų fakultete ir skaitė pranešimus šia tema. 10-ojoje konferencijoje autorės pranešimas pripažintas geriausiu vadybos sekcijoje. / There is a problem formulated in this master‘s work that there is no enaugh attention paid in Lithuania to understanding of pre-school teachers‘ carriers and factors affecting development of such carriers. Analized and systemized researches of foreign and domestic authors let us propose that motivation is the most important teachers‘ carrier prerequisite stimulated by objective (external) and subjective (internal) factors. Thesis makes an effort to set factors affecting carrier of preschool teacher. Researches had confirmed that current pre-school teachers' qualicifation improvement system may be an actual disatvantage in their carrier. Technical Competence is dominating orientation in the carrier of preschool teacher. Teachers agree that work in daycare may be related to their carrier, however only small percentage of teachers agree that their carrier is succesfull. Recomandations provided within this thesis will be used to improve above mentioned institutions, to motivate pedagogs to seek carrier, and highlite teachers‘ professional limitations. The autor of the thesis attended a tenth scientific works, named ,,The Topicality of Economies and Management’’ in the faculty of Social science of Šiauliai University on 23th of April in 2009 and on 22th of April in 2010. 10th Conference of the author the report was recognized as the best in management secion.

Thesis (Ph. D.)--University of Missouri--Columbia, 1997. / Typescript. Vita. Includes bibliographical references (leaves : 212-236). Also available on the Internet.