82 research outputs found
Indoor Wireless Communications using Slotted ISMA protocols
No full textThe performance of the Slotted ISMA protocols in Rician fading channel for Indoor Wireless communications considering Pico Cellular systems have been analyzed in this thesis. The throughput of Slotted nonpersistant Inhibit Sense Multiple Access (np-ISMA), Slotted 1-persistent ISMA (1p-ISMA) and Slotted np-ISMA\CD (Collision Detection) is investigated in the presence of n-interfering signals whose random amplitudes are considered as Rician distributed. Numerical results are presented, indicating the effect of propagation impairments on channel capacity. The results are of importance for mobile networks and indoor wireless office communications.Electrical Engineering, Mathematics and Computer ScienceTelecommunicatie- en Verkeersbegeleidingssysteme
Unslotted Hybrid CDMA/ISMA Protocol for Indoor Wireless Computer Communications
No full textA hybrid Code Division Multiple Access / Inhibit Sense Multiple Access (CDMA/ISMA) protocol has been proposed as an effective multiple access scheme for Indoor Wireless Computer Communications. This new protocol combines the advantages of both CDMA and ISMA into one protocol. On the one hand the ISMA protocol introduces a limitation to the number of simultaneous accesses to the transmission channel. On the other hand the CDMA protocol introduces an improvement to the packet survival chance. It is shown that the performance of the hybrid protocol is indeed better than CDMA only. In addition, code sharing can be applied to reduce hardware cost. The slotted hybrid CDMA/ISMA protocol using the p-persistent ISMA scheme has already been analysed. In this report, we investigate the hybrid protocol using the unslotted non-persistent ISMA scheme. The analysis is done for a star-connected multiple access wireless computer network. The performance comparison between the slotted and unslotted hybrid CDMA/ISMA protocol is evaluated in terms of throughput and delay using computer simulation and mathematical analysis.Electrical Engineering, Mathematics and Computer ScienceTelecommunicatie- en Verkeersbegeleidingssysteme
Performance Analysis of Slotted ISMA Protocols for Mobile Communications on a Three Lane Motorway
No full textA slotted ISMA protocol has been proposed for using with the communication channel from vehicles to a base station near the motorway. In this report the performance of this channel using the proposed protocol is analysed. Three slotted ISMA protocols can be distinguished, namely: • p-persistent slotted ISMA; • 1-persistent slotted ISMA; • non-persistent slotted ISMA. The performance of the protocol has been measured in terms of the throughput and the packet delay of the communication channel. The system has been modelled by assuming a capture receiver at the base station. The vehicles are assumed to maintain constant velocities while moving in one direction inside a cell of 200 metres on a three-lane motorway. The distribution of the vehicle positions on the motorway has been considered. Also the influence of the packet length and collision detection ratio will be examined. Furthermore the integration of DECT with the designed system is investigated. The performance of the system has been investigated for three traffic types: light traffic, heavy traffic and queuing traffic.Applied SciencesElectrical EngineeringTelecommunications and Traffic-Control Systems Grou
Performance Analysis of a Hybrid ISMA/CDMA Protocol for Indoor Wireless Communication
No full textThe hostile transmission medium encountered in Indoor: Wireless Communications (IWC) requires the use of special communication protocols. In this report we investigate a combination of the Inhibit Sense Multiple Access (ISMA) and Code Division Multiple Access (CDMA) protocols. The ISMA protocol limits the number of simultaneous accesses to the transmission channel and the CDMA protocol improves the packet survival chance. With CDMA each bit is transmitted using several code bits, giving each signal has its own, easy to recognize, signature. Coding spreads the signal over a large transmission bandwidth, which makes it particularly resistant to fading and multipath propagation, two key factors which degrade network performance…Applied SciencesElectrical EngineeringTelecommunications and Traffic Control Systems Grou
Hybrid CDMA / ISMA Protocol in Rician Fading Channel in Indoor Wireles Data Communications
No full textThis thesis describes the performance analysis of a star-connected, indoor wireless computer data communication system using direct-sequence code division multiple access (DS-CDMA) and Hybrid CDMA / Inhibit Sense Multiple Access (ISMA) protocol. The channel performance is investigated in terms of bit error rate (BER) and the protocol performance is investigated in terms of traffic-throughput and throughput-delay characteristics. To enhance the performance, a diversity technique using Maximum Ratio Combining (MRC) is used. Comparison of the simulation results with the analytical results is also performed.Applied SciencesElectrical EngineeringTelecommunications and Traffic Control Systems Grou
Throughput analysis of some mobile packet radio protocols in Rician fading Channels
No full textThe throughput of packet radio channels is investigated theoretically using the interference model in Rician fading environment. Three types of packet protocols are considered, namely: i) slotted ALOHA, ii) unslotted nonpersistent ISMA, and iii) slotted nonpersistent ISMA. Numerical results are presented, indicating the effect of propagation impairments on channel capacity. The results are of importance for mobile data networks, wireless office communications and other packet systems with contention-limited performance.Electrical Engineering, Mathematics and Computer ScienceTelecommunicatie- en Verkeersbegeleidingssysteme
INTEGRATION OF DA'WAH AND LOCAL CULTURE:: An Analysis Of The Ritual Of Wiwit Mbako In Temanggung
No full textThis paper explores the integration of Islamic da'wah with local culture through the Wiwit Mbako ritual, a traditional agricultural ceremony practiced in Temanggung, Central Java. The central research question investigates how Islamic values are communicated and embodied within this cultural tradition, particularly in the context of rural agrarian communities. Employing a qualitative approach, the study analyzes the Wiwit Mbako ritual as both a cultural and religious practice, focusing on key elements such as prayers (doa), communal meals (selamatan), and social gatherings (gotong royong). Through these ritualistic components, the paper examines how Islamic teachings—such as gratitude, trust in Allah, and communal solidarity—are contextualized and disseminated within a familiar, culturally resonant framework. The findings highlight the dual role of the Wiwit Mbako ceremony, which not only serves as an expression of thanksgiving for a successful tobacco harvest but also as a medium for Islamic da'wah, promoting social harmony and religious devotion. The paper concludes that the Wiwit Mbako ritual not only reaffirms the community's dependence on divine will but also strengthens the role of da'wah by blending Islamic messages with local customs, thereby enhancing their relevance and impact within an agrarian society. This fusion of religion and culture underscores the adaptability of Islamic da'wah in rural Indonesia, making it a vital tool for preserving both cultural identity and religious values
RANCANG BANGUN ALAT BANTU PRAKTIKUM FISIKA VISKOMETER BERBASIS INTERNET OF THINGS
No full textPenelitian ini bertujuan untuk merancang dan membangun alat bantu praktikum viskometer berbasis internet of things yang dapat meningkatkan pemahaman mahasiswa dalam pengukuran viskositas fluida. Dilakukan antara mei hingga juli 2025 dengan penelitian eksperimen. Pengujian yang dilakukan menggunakan 3 jenis fluida (Air Bersih, minyak goreng, dan oli mpx2), dengan suhu (28°C, 40°C, dan 60°C). Masing-masing viskositas nya yaitu Air Bersih pada suhu 28°C (0,00083 Pa.s), suhu 40°C (0,00066 Pa.s), dan suhu 60°C (0,00044 Pa.s). Viskositas pada minyak goreng suhu 28°C (0,0388 Pa.s), suhu 40°C (0,0249 Pa.s), dan suhu 60°C (0,0164 Pa.s). Oli Mpx2 suhu 28°C (0,0936 Pa.s), suhu 40°C (0,0634 Pa.s), dan suhu 60°C (0,0406 Pa.s). tingkat ketelitian alat mencapai 96,91% yang artinya sangat baik. Analisis ANOVA diperlukan untuk menunjukan bahwa fluida berpengaruh signifikan tehadap viskositas dengan nilai 1,08E-16, menunjukan bahwa P-value < Fcrit atau H1 diterima. Suhu berpengaruh signifikan terhadap viskositas dengan nilai 1,27E-09, hal ini menunjukan bahwa P-value < Fcrit atau H1 diterima. Dan hasil nilai P-value pada interaksi adalah sebesar 1,39E-07, menunjukan bahwa interaksi p-value < fcrit atau H1 diterima. Hasil ini membuktikan bahwa alat bantu praktikum viskometer berbasis intenet of things sesuai dengan teori fisika bahwa peningkatan suhu pada fluida mempengaruhi signifikan viskositas
Financial globalization: a description from the standpoint of a process approach = Фінансова глобалізація: характеристика з позицій процесного підходу
No full textOnyshchenko S.V. Financial globalization: a description from the standpoint of a process approach // Information Technologies and Management 2017 : theses of the 15th International Scientific Conference, April 27-28. – Riga : ISMA University, 2017. – P. 140-141.The complexity of the financial globalization process is caused not only by the presence of a significant number of subprocesses, their scale, and depth of consequences but also common consequences of these subprocesses, for which a synergistic effect is observed. Author proved that manifestation of financial globalization caused by the growth of financial markets and the priority development of the international financial sector in comparison with the real sector of the world economy.
The descriptive model of financial globalization from the position of process approach is proposed, taking into account the subjects and objects of financial globalization.Складність процесу фінансової глобалізації зумовлена не лише наявністю значної кількості підпроцесів, їх масштаб і глибину наслідків, а також спільні наслідки цих підпроцесів, для яких спостерігається синергетичний ефект.
Автором доведено, що прояв фінансової глобалізації зумовлений зростанням фінансових ринків та пріоритетним розвитком
міжнародний фінансовий сектор у порівнянні з реальним сектором світової економіки.
Запропоновано описову модель фінансової глобалізації з позиції процесного підходу з урахуванням суб’єктів та об’єктів фінансової глобалізації
Numerical simulation of impact noise generated at the railway insulated joint
No full textThis paper presents a full finite element (FE) model of wheel-track interaction to study the wheel-rail impact noise excited by an insulated joint (IJ). The integration is performed in the time domain with an explicit central difference scheme. The vibratory behaviour of the track and wheel model are respectively validated with hammer test and Axle Box Acceleration (ABA) measurement. By making use of the calculated velocities and pressures on the vibrating surfaces, the boundary element method (BEM) based on Helmholtz equation is adopted to transform the vibrations of the wheel-track into acoustic signals. The decay rate of impact noise at different frequency bands during propagation are analysed. The predictions of total impact noise radiation and the noise contributions of different track components are in good agreement with results reported in the literature, while the effective frequency range is successfully extended from 5 kHz to 10 kHz.Accepted Author ManuscriptRailway Engineerin
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