Optimal Compression and Transmission Rate Control for Node-Lifetime Maximization

We consider a system that is composed of an energy constrained sensor node and a sink node, and devise optimal data compression and transmission policies with an objective to prolong the lifetime of the sensor node. While applying compression before transmission reduces the energy consumption of transmitting the sensed data, blindly applying too much compression may even exceed the cost of transmitting raw data, thereby losing its purpose. Hence, it is important to investigate the trade-off between data compression and transmission energy costs. In this paper, we study the joint optimal compression-transmission design in three scenarios which differ in terms of the available channel information at the sensor node, and cover a wide range of practical situations. We formulate and solve joint optimization problems aiming to maximize the lifetime of the sensor node whilst satisfying specific delay and bit error rate (BER) constraints. Our results show that a jointly optimized compression-transmission policy achieves significantly longer lifetime (90% to 2000%) as compared to optimizing transmission only without compression. Importantly, this performance advantage is most profound when the delay constraint is stringent, which demonstrates its suitability for low latency communication in future wireless networks.Comment: accepted for publication in IEEE Transactions on Wireless Communicaiton

Media Pembelajaran Jaringan Kerja Metode Pert Berbasis Multimedia

Pembelajaran riset operasi materi jaringan kerja metode PERT bagi sebagian mahasiswa dirasa sulit untuk dipahami terutama dalam menentukan ES, LS dan Jalur Kritis. Prestasi belajar mahasiswa sering diindikasikan dengan permasalahan belajar dalam memahami materi. Kegiatan belajar di dalam kelas dengan lisan, tulisan bahkan slide powerpoint dapat menyebabkan pembelajaran menjadi kurang menarik dan cenderung membosankan. Penelitian ini bertujuan untuk membantu kegiatan perkuliahan riset operasi. Dengan adanya media pembelajaran berbasis multimedia ini diharapkan mahasiswa dapat meningkatkan pemahaman dan minat belajar dalam kegiatan belajar khususnya mengenai jaringan kerja metode PERT. Metode penelitian ini dilaksanakan dengan mengidentifikasi permasalahan, pengumpulan data melalui metode literature, interview dan kuesioner. Metode literatur dilakukan dengan studi pustaka yaitu membaca dan membandingkan buku dan artikel yang terkait. Wawancara dilakukan kepada riset operasi dosen pengampu mata kuliah. Penyebaran kuesioner terkait tentang perhitungan materi metode PERT. Data yang terkumpul digunakan untuk menganalisis user, kebutuhan user, kebutuhan sistem. Hasil analisis digunakan untuk membuat aplikasi pembelajaran jaringan kerja metode PERT berbasis multimedia dengan menggunakan software macromedia flash CS3. Hasil penelitian ini adalah aplikasi multimedia sebagai Media Pembelajaran Jaringan Kerja Metode PERT. Aplikasi telah diuji coba menggunakan black box test dan alpha test. Berdasarkan hasil uji coba tersebut dapat disimpulkan bahwa aplikasi pembelajaran ini dapat membantu proses pembelajaran mahasiswa dan dapat digunakan sebagai alat bantu pembelajaran jaringan kerja metode PERT

Meningkatkan Kualitas Hasil Belajar IPA Melalui Alternatif Model Pembelajaran

The purpose of this research is to know the influence of certain teaching method in increasing the quality of the students\u27 achievement of open SLTP viewed from the kind of tests. Besides, it is directed to get the most effective teaching method which can be applied as the positive alternative in increasing the quality of the SLTP student\u27 achievement. The kind of research used is an experimental comparative research using two ways Anava. Here statistical formulas were three levels comparative from one variable namely teaching method with module; teaching method with videocassette (electronic media); and teaching method with problem solving approach, and their influence to the tied variable based on other factor whether the test is objective or essay. The result of the research shows that teaching method with electronic media is the most appropriate to increase the quality of studying biology; the second was teaching by module completed with creative problems solving, and the last was teaching method with module. Besides, it revealed that subjective test model is better than objective test. There was no interaction between certain teaching methods with the kind of the test

Analytic study of clinical presentation of intracranial space-occupying lesions in adult patients

Intracranial space-occupying lesions can be caused by a variety of disease processes, ranging from neoplasms to non-neoplastic lesions including hematomas, abscesses and vascular malformations. This article provides an overview of varied clinical presentations of patients with intracranial space-occupying lesions.Methods:A total of 200 cases of intracranial space-occupying lesions presenting at Neuro Clinic and Care were retrospectively analyzed. Adult patients from all age groups and both genders were included in this study. Results: 165 patients (82.5%) had neoplastic lesions while 35 (17.5%) had non-neoplastic lesions. Metastatic lesions from primary tumor elsewhere in the body comprised the most common group with81 cases (40.5%), followed by meningiomas with 27 cases (13.5%). Males were affected slightly more than females (1:0.8). The most common presenting symptom was headache 87 patients (43.5%,) followed by focal symptoms such as numbness, tingling or weakness being present in 80 (40%)and seizures observed in 65 (32.5%).Conclusion: The study reviews the wide range of symptoms the patients with intracranial space-occupying lesions present with, the most common being headache, followed by focal symptoms such as numbness, tingling or weakness, seizures and vomiting. Knowledge of these typical as well as atypical patterns of clinical presentation can aid physicians in timely detection and prompt application of diagnostic and therapeutic modalities