Thesis (M.S)--Ohio University, March, 2005. / Includes bibliographical references (p. 102-105)

Thesis (M.S)--Ohio University, March, 2005. / Title from PDF t.p. Includes bibliographical references (p. 102-105)

<p>In today's GSM system there is a complex resource situation when it comes to the scarce TDMA channels in the air interface, the time slots. There are both voice call services that use one or a half time slot and there are packet data users, that may share time slots with other packet data users, and they can use multiple channels at the same time. Allocating time to users is a crucial part in the system and it may affect the performance for the end user substantially.</p><p>In the future there may be more types of services than just voice and packet data and that these services may have specific demands on their channels, time slots. That means they would not be able to use just any of the available channels. The way to "give" services channels is what is called channel allocation. In this thesis four different services and three different principles for channel allocation is implemented in a Matlab simulator and simulated. The thesis goal is to determine which principle is best for which mix of services.</p><p>The principles that have been investigated are Flexible Algorithm that lets all services use all channels, Fix Dedication Algorithm where all channels are dedicated to a service and only can be used by that one and finally Soft Dedication Algorithm where all channels are dedicated to a service but may be used by other services when it is not needed by the preferred one.</p><p>The conclusion is, simplified, that the Soft Dedication Algorithm generates low blocking rates, high bandwidth and that it is a quite robust principle although the borrowing user may be preempted. It may not always be the best one but over all it is the one to prefer.</p> / <p>Detta examensarbete är utfört på uppdrag av och i samarbete med Ericsson och rör kanal- och resurshantering i GSM-systemet.</p><p>Ett ständigt problem vid trådlös och mobil kommunikation är den begränsade mängd frekvenser som finns tillgängliga i radiogränssnittet och hur pass nära två radioresursers frekvenser kan ligga varandra. I GSM används TDMA (Time Division Multiple Access) för att få plats med många användare på ett smalt frekvensband. TDMA innebär förenklat att tiden delas upp i åtta tidsluckor och att varje användare får tillgång till en av radioresurserna under en sådan tidslucka (kanal). Detta gäller både i upp- och nedlänk.</p><p>I nuläget finns två tjänster, paketdata och tal, som använder tidsluckorna på olika sätt. En talanvändare använder en eller en halv lucka själv medan paketdataanvändare kan dela på en eller flera luckor. Det finns alltså en mängd olika sätt att allokera, "dela ut", dessa luckor till ett givet antal användare. I nuläget har man en väl fungerande algoritm för detta men man tror att det i framtiden kommer att finnas fler tjänster med mer specifika krav på sina tidsluckor (kanaler) och att man då inte längre kan använda samma princip för kanalallokeringen.</p><p>I detta exjobb har tre nya, enkla och renodlade principer för kanalallokering undersökts för fyra fiktiva tjänster. Det tre principerna är Flexible Algorithm, där alla tjänster tillåts använda alla kanaler, Fix Dedication Algorithm, där alla kanaler är dedicerade till någon tjänst och endast kan användas av just denna tjänst; och slutligen Soft Dedication Algorithm som fungerar liknande den föregående men här kan tjänster "låna" kanaler av andra tjänster så längs som de är lediga. I Soft Dedication Algorithm kan en eventuell "låntagare" bli avbruten om en användare av rätt tjänst inte hittar en ledig kanal.</p><p>Utvärdering har skett genom att simulera systemet i en, delvis egengjord, Matlabsimulator.</p><p>Resultaten visar, förenklat, att Soft Dedication Algorithm är den bästa vad gäller låg blockering, kanalutnyttjande och även bandbredder. Den är även förhållandevis robust mot variationer i last.</p>

In today's GSM system there is a complex resource situation when it comes to the scarce TDMA channels in the air interface, the time slots. There are both voice call services that use one or a half time slot and there are packet data users, that may share time slots with other packet data users, and they can use multiple channels at the same time. Allocating time to users is a crucial part in the system and it may affect the performance for the end user substantially. In the future there may be more types of services than just voice and packet data and that these services may have specific demands on their channels, time slots. That means they would not be able to use just any of the available channels. The way to "give" services channels is what is called channel allocation. In this thesis four different services and three different principles for channel allocation is implemented in a Matlab simulator and simulated. The thesis goal is to determine which principle is best for which mix of services. The principles that have been investigated are Flexible Algorithm that lets all services use all channels, Fix Dedication Algorithm where all channels are dedicated to a service and only can be used by that one and finally Soft Dedication Algorithm where all channels are dedicated to a service but may be used by other services when it is not needed by the preferred one. The conclusion is, simplified, that the Soft Dedication Algorithm generates low blocking rates, high bandwidth and that it is a quite robust principle although the borrowing user may be preempted. It may not always be the best one but over all it is the one to prefer. / Detta examensarbete är utfört på uppdrag av och i samarbete med Ericsson och rör kanal- och resurshantering i GSM-systemet. Ett ständigt problem vid trådlös och mobil kommunikation är den begränsade mängd frekvenser som finns tillgängliga i radiogränssnittet och hur pass nära två radioresursers frekvenser kan ligga varandra. I GSM används TDMA (Time Division Multiple Access) för att få plats med många användare på ett smalt frekvensband. TDMA innebär förenklat att tiden delas upp i åtta tidsluckor och att varje användare får tillgång till en av radioresurserna under en sådan tidslucka (kanal). Detta gäller både i upp- och nedlänk. I nuläget finns två tjänster, paketdata och tal, som använder tidsluckorna på olika sätt. En talanvändare använder en eller en halv lucka själv medan paketdataanvändare kan dela på en eller flera luckor. Det finns alltså en mängd olika sätt att allokera, "dela ut", dessa luckor till ett givet antal användare. I nuläget har man en väl fungerande algoritm för detta men man tror att det i framtiden kommer att finnas fler tjänster med mer specifika krav på sina tidsluckor (kanaler) och att man då inte längre kan använda samma princip för kanalallokeringen. I detta exjobb har tre nya, enkla och renodlade principer för kanalallokering undersökts för fyra fiktiva tjänster. Det tre principerna är Flexible Algorithm, där alla tjänster tillåts använda alla kanaler, Fix Dedication Algorithm, där alla kanaler är dedicerade till någon tjänst och endast kan användas av just denna tjänst; och slutligen Soft Dedication Algorithm som fungerar liknande den föregående men här kan tjänster "låna" kanaler av andra tjänster så längs som de är lediga. I Soft Dedication Algorithm kan en eventuell "låntagare" bli avbruten om en användare av rätt tjänst inte hittar en ledig kanal. Utvärdering har skett genom att simulera systemet i en, delvis egengjord, Matlabsimulator. Resultaten visar, förenklat, att Soft Dedication Algorithm är den bästa vad gäller låg blockering, kanalutnyttjande och även bandbredder. Den är även förhållandevis robust mot variationer i last.

This dissertation includes three papers that address various aspects of the economics of labour and the family. The dissertation integrates the discussion on the following issues: (1) the allocation of housework and childcare in Canadian two-earner households (2) the effect of family policy reform on time allocation and labour supply in two-parent families (3) effect of anticipated divorce and divorce duration on male and female labour supply. The first paper Time Allocation Gender Gap in Native-born and Foreign-born Families in Canada focuses on the difference between the housework and childcare share produced by foreign-born husbands compared to Canadian-born husbands. This empirical analysis employs the data from the Canadian General Social Survey. The results show that foreign-born husbands have a lower share of housework and childcare compared to their Canadian-born counterparts. The second paper The effect of Quebec childcare policy change on the labour market outcomes and time distribution in the family analyzes the effect of the childcare policy change that took place in Quebec in 1997-2000. The results show that the introduction of “$5 per day” daycare subsidized by the Quebec government increased the labour supply of married mothers and also affected the allocation of time husbands and wives spend on housework and childcare. The data from this project were drawn from 1996 and 2001 Canadian Census. The third paper Labour supply of Australian men and women before and after divorce studies the changes in the labour supply of men and women before and after divorce. The data for empirical analysis employs 12 waves of Household, Income and Labour Dynamics in Australia Survey (HILDA). The outcome suggests that men and women do not change labour participation and weekly working hours in anticipation of divorce. Women increase labour force participation and weekly hours worked as a result of divorce. Men’s labour supply does not change in response to divorce.

In this study, we investigate pupils’ perceptions in Swedish 3 of the allocation of time of the Canons of Rhetoric when working with oral presentations. We also investigate which relations that exist between pupils’ perceptions of the allocation of time of the Canons of Rhetoric and perceptions of knowledge of the Canons of Rhetoric as well as perceptions of their oral presentation. The study was conducted via a questionnaire and carried out among 245 pupils. Raw data has been analysed to determine the descriptive statistics of the allocation of time of the Canons of Rhetoric and tests for statistical significance have been performed to determine the effects that the allocation of time has on pupils’ perceptions of their oral presentation. We have analysed our results by the use of the cognitive and the socio-cultural perspective. Results show that pupils feel that no phase is given sufficient time and that they believe the three first phases to be higher prioritised than the remaning phases. The amount of class hours is of importance to the perceived knowledge of the Canons of Rhetoric, how easy pupils find it creating a presentation, their sense of preparation and the perceived development as a speaker. Regarding response, emendatio, the time for teacher response does not show any significant correlation to pupils’ perceptions of their oral presentation. If peer response is given before presentations, it has a positive effect on pupils’ satisfaction with the presentation, but has otherwise no influence. In addition, teachers’ scaffolding seems to have a larger effect on pupils’ perceptions of their oral presentation than teacher and peer response. Finally, self-assessment occurs to a low extent and is shown to affect the knowledge of the Canons of Rhetoric and how easy it is creating a presentation in a positive manner.

In this thesis, the problem of optimal resource allocation in real-time systems is studied. A recently proposed resource allocation approach called Q-RAM (Quality of Service based Resource Allocation Model) is investigated in detail. The goal of the Q-RAM based approaches is to minimize the execution speed in real-time systems while meeting resource constraints and maximizing total utility. Phased array radar system is an example of a system in which multiple tasks contend for multiple resources in order to satisfy their requirements. In this system, multiple targets are tracked (each a separate task) by the radar system simultaneously requiring processor and energy resources of the radar system. Phased array radar system is considered as an illustrative application area in order to comparatively evaluate the resource allocation approaches. For the problem of optimal resource allocation with single resource type, the Q-RAM algorithm appears incompletely specified, namely it does not have a termination criteria set that can terminate the algorithm in all possible cases. In the present study, first, the Q-RAM solution approach to the radar resource allocation problem with single resource type is extended to give a global optimal solution in all possible termination cases. For the case of multiple resource types, the Q-RAM approach can only generate near-optimal results. In this thesis, for the formulated radar resource allocation problem with multiple resource types, the Methods of Feasible Directions are considered as an alternative solution approach. For the multiple resource type case, the performances of both the Q-RAM approach and the Methods of Feasible Directions are investigated in terms of optimality and convergence speed with the help of Monte-Carlo simulations. It is observed from the results of the simulation experiments that the Gradient Projection Method produce results outperforming the Q-RAM approach in closeness to optimality with comparable execution times.

In this thesis, mathematical modeling and heuristic approaches are developed for surface-to-air weapon-target allocation problem with time varying single shot hit probabilities (SSHP) against linearly approaching threats. First, a nonlinear mathematical model for the problem is formulated to maximize sum of the weighted survival probabilities of assets to be defended. Next, nonlinear objective function and constraints are linearized. Time varying SSHP values are approximated with appropriate closed forms and adapted to the linear model obtained. This model is tested on different scenarios and results are compared with those of the original nonlinear model. It is observed that the linear model is solved much faster than the nonlinear model and produces reasonably good solutions. It is inferred from the solutions of both models that engagements should be made as late as possible, when the threats are closer to the weapons, to have SSHP values higher. A construction heuristic is developed based on this scheme. An improvement heuristic that uses the solution of the construction heuristic is also proposed. Finally, all methods are tested on forty defense scenarios. Two fastest solution methods, the linear model and the construction heuristic, are compared on a large scenario and proposed as appropriate solution techniques for the weapon-target allocation problems.

Abstract In this study, we investigate pupils’ perceptions in Swedish 3 of the allocation of time of the Canons of Rhetoric when working with oral presentations. We also investigate which relations that exist between pupils’ perceptions of the allocation of time of the Canons of Rhetoric and perceptions of knowledge of the Canons of Rhetoric as well as perceptions of their oral presentation. The study was conducted via a questionnaire and carried out among 245 pupils. Raw data has been analysed to determine the descriptive statistics of the allocation of time of the Canons of Rhetoric and tests for statistical significance have been performed to determine the effects that the allocation of time has on pupils’ perceptions of their oral presentation. We have analysed our results by the use of the cognitive and the socio-cultural perspective. Results show that pupils feel that no phase is given sufficient time and that they believe the three first phases to be higher prioritised than the remaning phases. The amount of class hours is of importance to the perceived knowledge of the Canons of Rhetoric, how easy pupils find it creating a presentation, their sense of preparation and the perceived development as a speaker. Regarding response, emendatio, the time for teacher response does not show any significant correlation to pupils’ perceptions of their oral presentation. If peer response is given before presentations, it has a positive effect on pupils’ satisfaction with the presentation, but has otherwise no influence. In addition, teachers’ scaffolding seems to have a larger effect on pupils’ perceptions of their oral presentation than teacher and peer response. Finally, self-assessment occurs to a low extent and is shown to affect the knowledge of the Canons of Rhetoric and how easy it is creating a presentation in a positive manner.

Recent years have witnessed a surge in demand for infrastructure and services to cover high demands on processing big chunks of data and applications resulting in a mega Cloud Datacenter. A datacenter is of high complexity with increasing difficulties to identify, allocate efficiently and fast an appropriate host for the requested virtual machine (VM). Establishing a good awareness of all datacenter’s resources enables the allocation “placement” policies to make the best decision in reducing the time that is needed to allocate and create the VM(s) at the appropriate host(s). However, current algorithms and policies of placement “allocation” do not focus efficiently on awareness of the resources of the datacenter, and moreover, they are based on conventional static techniques. Which are adversely impacting on the allocation progress of the policies. This thesis proposes a new Agent-based allocation/placement policy that employs some of the Multi-Agent system features to get a good awareness of Cloud Datacenter resources and also provide an efficient allocation decision for the requested VMs. Specifically, (a) The Multi-Agent concept is used as a part of the placement policy (b) A Contract Net Protocol is devised to establish good awareness and (c) A verification process is developed to fully dimensional VM specifications during allocation. These new results show a reduction in response time of VM allocation and the usage improvement of occupied resources. The proposed Agent-based policy was implemented using the CloudSim toolkit and consequently was compared, based on a series of typical numerical experiments, with the toolkit’s default policy. The comparative study was carried out in terms of the time duration of VM allocation and other aspects such as the number of available VM types and the amount of occupied resources. Moreover, a two-stage comparative study was introduced through this thesis. Firstly, the proposed policy is compared with four state of the art algorithms, namely the Random algorithm and three one-dimensional Bin-Packing algorithms. Secondly, the three Bin-Packing algorithms were enhanced to have a two-dimensional verification structure and were compared against the proposed new algorithm of the Agent-based policy. Following a rigorous comparative study, it was shown that, through the typical numerical experiments of all stages, the proposed new Agent-based policy had superior performance in terms of the allocation times. Finally, avenues arising from this thesis are included.