A Pricing-Based Cooperative Spectrum Sharing Stackelberg Game

We consider the problem of cooperative spectrum sharing among a primary user (PU) and multiple secondary users (SUs) under quality of service (QoS) constraints. The SUs network is controlled by the PU through a relay which gets a revenue for amplifying and forwarding the SUs signals to their respective destinations. The relay charges each SU a different price depending on its received signal-to-interference and-noise ratio (SINR). The relay can control the SUs network and maximize any desired PU utility function. The PU utility function represents its rate, which is affected by the SUs access, and its gained revenue to allow the access of the SUs. The SU network can be formulated as a game in which each SU wants to maximize its utility function; the problem is formulated as a Stackelberg game. Finally, the problem of maximizing the primary utility function is solved through three different approaches, namely, the optimal, the heuristic and the suboptimal algorithms.Comment: 7 pages. IEEE, WiOpt 201

Pelatihan Public Speaking Bagi Siswa SMA Kristen Mercusuar Kupang

Persoalan utama ketika orang berbicara di depan umum adalah rasa takut dan tidak percaya diri. Hal ini bisa terjadi pada siapa saja terutama siswa dalam proses belajar di sekolah. Analisis situasi tim PKM pada siswa SMA Mercusuar menemukan adanya masalah ketika siswa berbicara di depan umum. Tujuan pelatihan ini untuk melatih siswa berbicara di depan umum. Public speaking merupakan komunikasi lisan berupa ceramah, presentasi, pidato, mempimpin sebuah acara, pembawa acara, moderator, presenter, penyiar, host, dan sebagainya. Dalam melaksanakan kegiatan ini tim PKM melakukan tahap perencanaan dan pelaksanaan. Tahap perencanaan meliputi survei, wawancara, dan observasi pada sekolah. Sedangkan tahap pelaksanaan meliputi pelatihan, pemberian materi, praktek dan post test. Hasil pelatihan menunjukkan bahwa siswa Mercusuar dapat mempraktekkan teknik dasar public speaking mulai dari perkenalan dan ice breaking, experiential learning, merangkai kata penuh makna, melatih performance dalam public speaking, sum-up session dan closing. Hasil pelatihan juga menunjukkan siswa yang mempunyai pengetahuan baik tentang public speaking sebanyak 18 orang (80%). Sedangkan siswa yang mempunyai pengetahuan cukup sebanyak 2 orang (20%). Ada perubahan pengetahuan siswa tentang public speaking yang signifikan. Kata Kunci: pelatihan, public speaking, sisw

Raman Optical Activity Using Twisted Photons

Raman optical activity underpins a powerful vibrational spectroscopic technique for obtaining detailed structural information about chiral molecular species. The effect centers on the discriminatory interplay between the handedness of material chirality with that of circularly polarized light. Twisted light possessing an optical orbital angular momentum carries helical phase fronts that screw either clockwise or anticlockwise and, thus, possess a handedness that is completely distinct from the polarization. Here a novel form of Raman optical activity that is sensitive to the handedness of the incident twisted photons through a spin-orbit interaction of light is identified, representing a new chiroptical spectroscopic technique

Substantial Effect of Fenugreek Seeds Aqueous Extract on Serum Estradiol Level in Ovarian Hyperstimulation Syndrome Rat Model

Objectives: Estradiol (E2) plays an important role in the pathophysiology of ovarian hyperstimulation syndrome (OHSS). This study aimed to evaluate the effect of fenugreek seed aqueous (FSA) extract on serum E2 levels in a rat model of OHSS. Methods: A total of 34 female Sprague Dawley rats, aged 18 days old, weighing 40 to 45 g, were randomly divided into negative control, positive control, and treatment groups. A daily dose of 1500 mg/kg per body weight of FSA extract was administrated orally to rats in the treatment group for 13 days. On day eight of the study, OHSS was induced in both positive control and treated groups by subcutaneous injection of pregnant mare’s serum gonadotropin 50 IU for four consecutive days, followed by human chorionic gonadotropin 25 IU on the fifth day. The effect of FSA extract was evaluated by measuring the concentration of serum E2 using the enzyme-linked immunosorbent assay. Results: FSA extract reduced serum E2 level significantly in the treated OHSS model (p-value < 0.050) compared to the positive control group. Conclusions: The finding has important implications on the development of female infertility adjuvant drugs for safe assisted reproduction technology cycles in terms of OHSS prevention

Remembering the Sea: Personal and Communal Recollections of Maritime Life in Jizan and the Farasan Islands, Saudi Arabia

This is the final version of the article. Available from the publisher via the DOI in this record.People create narratives of their maritime past through the remembering and forgetting of seafaring experiences, and through the retention and disposal of maritime artefacts that function mnemonically to evoke or suppress those experiences. The sustenance and reproduction of the resulting narratives depends further on effective media of intergenerational transmission; otherwise, they are lost. Rapid socio-economic transformation across Saudi Arabia in the age of oil has disrupted longstanding seafaring economies in the Red Sea archipelago of the Farasan Islands, and the nearby mainland port of Jizan. Vestiges of wooden boatbuilding activity are few; long-distance dhow trade with South Asia, the Arabian-Persian Gulf and East Africa has ceased; and a once substantial pearling and nacre (mother of pearl) collection industry has dwindled to a tiny group of hobbyists: no youth dive today. This widespread withdrawal from seafaring activity among many people in these formerly maritime-oriented communities has diminished the salience of such activity in cultural memory, and has set in motion narrative creation processes, through which memories are filtered and selected, and objects preserved, discarded, or lost. This paper is a product of the encounter of the authors with keepers of maritime memories and objects in the Farasan Islands and Jizan. An older generation of men recall memories of their experiences as boat builders, captains, seafarers, pearl divers and fishermen. Their recounted memories are inscribed, and Arabic seafaring terms recorded. The extent of the retention of maritime material cultural items as memorials is also assessed, and the rôle of individual, communal and state actors in that retention is considered. Through this reflection, it becomes clear that the extra-biological memory and archive of the region’s maritime past is sparse; that intergenerational transmission is failing; that the participation of state agencies in maritime heritage creation is highly limited; and that, as a result, memories current among the older generation have limited prospect of survival. These memories, recorded and interpreted here, identify the Farasan Islands as a former centre of the pearling industry in the Red Sea, and identify them and Jizan as open to far-reaching maritime-mediated cultural influences in an era before the imposition of the attributes of the modern nation-state.This study was funded by the Golden Web Foundation (UK registered charity number 1100608), with additional support from the Seven Pillars of Wisdom Trust (UK registered charity number 208669)