Abstract— Transport modes are very important to Libyan’s Tripoli residents for their daily trips. However, the total number of own

car and private transport namely taxi and micro buses on the road increases and causes many problems such as traffic congestion,

accidents, air and noise pollution. These problems then causes other related phenomena to the travel activities such as delay in trips,

stress and frustration to motorists which may affect their productivity and efficiency to both workers and students. Delay may also

increase travel cost as well inefficiency in trips making if compare to other public transport users in some Arabs cities. Switching to

public transport (PT) modes alternatives such as buses, light rail transit and underground train could improve travel time and travel

costs. A transport study has been carried out at Tripoli City Authority areas among own car users who live in areas with inadequate

of private transport and poor public transportation services. Analyses about relation between factors such as travel time, travel cost,

trip purpose and parking cost have been made to answer research questions. Logistic regression technique has been used to analyse

these factors that influence users to switch their trips mode to public transport alternatives.

Keywords --- Own car, private transport, public transport, parking cost, logistic regression.

ABSTRACT:

The own car is the first most common mode of transportation using in Tripoli. About 66 % Tripoli’s

resident prefer and used own car for all trips propose and 34 % who’s prefer to use the private

transport such as private taxi and private buses namely (micro bus with capacity from 8 to 16 person)

in Tripoli city. The rapid increase in the use of own car model transport with the poor public transport

system in Tripoli as caused acute traffic jam, accidents, environmental impacts such as (air pollution

and noise) and land use damage for building more new car parks. In this paper, policy aimed at

discouraging the use own car and private transport in the Tripoli city. Also this paper research to

identify factors that prevent own car and private transport users from used public transport so that

logical policies could be formulated to support greater use of public transport. A survey was carried

out on users of own cars and private transport namely (private taxi and private buses) (n= 900).

Descriptive and analytical transportation issue is the main research methodology in this paper. The

most important variables found likely to support the use of public transport were reduced travel time;

reduce the distance from home to public transport stop and suitable fares. In conclusion for the

traveller to change from private vehicles to public transport, proper incentives need to be provided for

better performance.

Keywords: Own car, Private transport, poor public transport, Descriptive and analytical

ABSTRACT

Most of the Arabic capitals cities are suffering from severe traffic congestion as a result of

continuing increase in both road users and private vehicle ownerships. Tripoli capital city of Libya

is one of these cities where majority of the travellers prefer to using private transportation mode

namely own cars which is 88% of the traffic volume for work, study and shop trips. Government

statistical data on the city for October 2009 revealed that out of the total 945,203 vehicles

comprised of 743,796 own cars and 47,031 units of taxis and micro buses. This paper evaluates

traffic characteristics on the three main entrances into the city; the southern entrance covers the AlGabis, Airport Road and Al-Hadaba (Salah Al-Din) entrances; the west entrance includes Al-Giran

entrance; and the east covers Tajora (Al-Bive) entrance. The entrance routes lead to several

downtown roads and main streets in the city, such as two way Omar Al-Mukhtar Street, Mizran

Street, First of September Street at the city centre and Al-Fatah Street along the Tripoli city port.

There are also other old and modern streets traverses in the city centre. As the number of private

cars usage increased, the traffic congestion got more acute. Tripoli streets need to expedite and

support the use of public transportation system namely bus, train and light rail transit into the city.

A questionnaire survey was carried out in Tripoli area to explore the potential reduction of private

cars usage on road through optimal use of suitable public transportation system.

Key words: Traffic volume, traffic congestion, public transport, entrances

Due to the inherent complexity of decision making in supply chain management (SCM), there is a growing need for modelling supply chain systems with different methodologies. A large number of manufacturing organisations in particular the cement industry in Libya is seeking techniques that can help, identify and implement strategies for developing and improving their supply chain network. Developing a supply chain management system requires the analysis of the manufacturing processes from the initial sourcing to the end customers. The paper reports that the Libyan cement industry has problems related to its productivity. In order to face these problems, cement factories need to increase their production. To accomplish this, they require a clear strategy towards an efficient supply chain.

In this paper, the performance of limited feedback precoded spatial multiplexing multiple-input multiple-output orthogonal frequency division multiplexing (MIMO - OFDM) systems is investigated in time varying fading channels. Most studies into limited feedback precoded (MIMO - OFDM) systems are based on the notion of time invariant channels throughout transmission. Therefore, the precoding matrix for each subcarrier can be designed at the receiver in terms of the current channel state, fed back to the transmitter, and used for the subsequent block of data symbols. However, in time varying channels, the feedback information becomes outdated, which results in significant system performance degradation. To mitigate this system performance degradation caused by outdated information due to a delay in the feedback channel, this paper considers a more practical system, where the channel varies from one block

Conventional precoded spatial multiplexing multiple-input multiple-output (MIMO) systems using limited feedback are mainly based on the notion of time invariant channels throughout transmission. Consequently, the precoding matrix can be found during the training symbols and used over the subsequent data symbols. In this study, the authors consider a more practical system where the channel varies from one block of symbols to another. In such a scenario, the precoding matrix designed at the receiver based on the previous training symbols becomes outdated, which results in significant system performance degradation. In order to avoid this problem and reduce performance degradation, the authors propose the use of a Kalman filter linear predictor at the receiver to provide the transmitter with the precoding matrix for the next block of symbols. The performance of this method is assessed using computer …

Abstract: Own cars are the most common mode of transport in Tripoli, Libya. About 66% of

Tripoli’s residents prefer to use their own cars and only 34% resort to depend on public transports

namely taxi, coaches and microbuses for their transportation activities in the city centre area. Rapid

increase in own cars’ usage, coupled with no public transport system have caused problems such as

acute traffic congestion, an increase in road accidents, deterioration in environmental well being and

unbalanced land use characteristics. A questionnaire survey was carried out in Tripoli to address the

first two of these problems. About 900 respondents were analysed where their needs were observed

and expectations explored. The study has found that the variables to support the use of public

transport system are the reductions in travel time, distance travelled and reasonable fares. The study

also identifies some factors that prevent the users of private cars, taxi, coaches and microbuses from

using the public transportation system, in order to enable the researcher to suggest and formulate

logical policies to support better use of public transportation system.

Key words: Own car, public transport, public transport system, Descriptive and analytical

Precoded spatial multiplexing multiple-input multiple-output (MIMO) systems using limited feedback are mainly based on the notion of delay-free feedback channels. In this paper, we take into account the time varying nature of the channel, and consider the feedback delay problem. In order to reduce performance degradation of spatial multiplexing systems in the presence of feedback delay, we propose the use of a Kalman filter linear predictor at the receiver to provide the transmitter with the predicted channel state information, and hence, mitigate the effect of feedback delay. The performance of this method is assessed using computer simulation, and the obtained results for the proposed channel prediction scheme demonstrate improved bit error rate performance for time varying Rayleigh fading channels.

A new physical, compact and continuous Model for extremely Scaled MOSFET Device is formulated, based on the Maxwellian approximation where the electron temperature is controlled by acoustic phonon scattering which simultaneously includes the hot electrons and the thermoelectric effects. The demonstration involving predicted current voltage characteristics and ring oscillator propagation delays reveals a significant benefit of velocity overshoot is also presented for circuit simulation. The extracted model describes current characteristics from linear to saturation operating regions with a single IV expression, and guarantees the continuities of Ids, conductance and their derivative throughout all Vgs, Vbs and Vds bias conditions. The model has been implemented in the circuit simulation such as HSPICE, Smart Spice and BSIM4v6. The new model has extensive built-in dependencies of important dimensional and processing parameters. Furthermore, the model accounts for all the major physical effects of the MOSFET characteristics.

Precoded spatial multiplexing multiple-input multiple-output (MIMO) systems using limited feedback have been extensively studied to reduce the feedback information based on the notion of delay-free feedback channel. In order to reduce performance degradation of precoded spatial multiplexing MIMO systems due to delay in the feedback channel, in this paper, we take into account the time varying nature of the channel, and consider the feedback delay problem. We propose the use of a linear predictor at the receiver to provide the precoder at the transmitter with predicted channel state information, and hence, mitigate the effect of feedback delay. The predictor is implemented using Kalman filter. The performance of this method is evaluated using computer simulation, and the achieved results demonstrate improved bit error rate performance in frequency selective Rayleigh fading channels.