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In this work, we present the design and experimental demonstration of the first micro-resonator-based tunable hysteresis comparator. The proposed design employs an electrostatically driven clamped-clamped microbeam operated in the nonlinear regime. The design operation is assigned such that both the resonator’s drive frequency and beam bias can be utilized to tune the nonlinear dynamic behavior of the resonator. This tunable nonlinear behavior allows the device to exhibit a hysteretic voltage response with a tunable hysteresis voltage range. In the frequency tuning scheme, the hysteresis range is directly proportional to the driving frequency shift, with a maximum hysteresis portion of 51.4% achievable. In the voltage tuning scheme, the hysteresis range exhibits a linear relationship with the bias voltage variance without compromising tunability. Moreover, the voltage tuning scheme provides a simpler solution as it simplifies the complexity of the control system and provides a better stable and repeatable control capability. The proposed resonator-based comparator has many additional benefits, including stable electrical properties, a long lifetime due to the elimination of physical contact, and a wide tuning hysteresis range. Furthermore, the device has the potential for large voltage swing (~20V) interfacing in the microresonator-based electronics field. This high-voltage handling capability of our proposed resonator-based hysteresis comparator broadens its applicability, rendering it compatible with high-voltage systems. [2023-0084]

A project to restore the function of an ancient Nabatean flood control system that had previously protected the Plaza of the Treasury (Al-Khazna), Petra, is described herein. The project involves a large, multidisciplinary team, numerous stakeholders, and a difficult setting. It involves training, outreach, documentation, archaeological investigation, hydrological modeling, architectural conservation and rehabilitation. Previous studies had indicated that such flood control systems operate by controlling water flow from the headwaters in order to prevent sudden surges of water. Since Petra often suffers from the effects of flash floods, the Petra Development and Tourism Regional Authority (PDTRA) asked the researchers to explore the possibility of controlling modern-day floods using these systems. This culminated in the partial rebuilding of the flood control system and important lessons on their limitations and how they work.

This paper aims to examine the provenance of Roman marble statues uncovered from the Eastern Roman Baths (Gerasa of the Decapolis, Jordan) during the 2016 and 2017 excavation campaigns. The samples were characterized using magnifying lenses, an x-ray diffractometer, a stable isotope mass spectrometer, and a polarized light microscope. The results show that the Aphrodite and drapery marbles are dolomitic and most probably from the Cape Vathy of Thassos Island (Greece); the Asklepios and Zeus marbles are fine-grained and most probably from Docimium (Turkey); the Melopmene, Demetrius Aphrodite, and eagle marbles are fine-grained and most probably from Penteli (Greece); the dancing satyr and Apollo marbles are coarse-grained and most probably from Lakkos (Paros Island, Greece); and the marble fragments of unknown statues are coarse-grained and most probably from Marmara (Proconnesus-1) Island, Turkey. The results indicate that sculptors preferred fine white marbles for carving sculptures in spite of their source, price, and sculpture workshop. The results agree with previous studies that showed a wide variety of marble sources, indicating that Gerasa prospered in its location on the King’s Highway and participated in a well-established trade network with the major cities and marble sources in the Roman Empire.

Observations have shown that the state of preservation of mosaics in the 6th Century churches of Gerasa(modern Jarash) is generally better than the later ones that date to the 7th century. An investigation of the composition and texture of the mortars used in the production of the mosaics was undertaken in order to understand the reason for this.