Mode and polarization-division multiplexing technologies (MDM and PDM)can offer considerable parallelism for optical multiplexing biosensors, complex optical neural networks, and high-capacity optical interconnects, while requiring only a single-wavelength laser source. Thanks to the mature fabrication processes of silicon nitride and superior material properties of lithium niobate, the silicon nitride loaded lithium niobate on insulator (LNOI) platform allows the integration of high-speed optical modulators and optical (de)multiplexing devices to achieve high-capacity and low-cost photonic integrated circuits suitable for data communication applications. In this contribution, MDM and PDM are investigated in a silicon nitride loaded LNOI (X-cut) platform. As a proof of concept, an asymmetrical directional coupler-based mode ( de)multiplexer (MMUX) and polarization splitter-rotator (PSR) are designed, fabricated, and experimentally demonstrated. The measured insertion losses are lower than 1.46 and 1.49 dB, while the inter-modal crosstalk is lower than −13.03 and −17.75 dB for the MMUX and PSR, respectively, for a wavelength range of 1525-1565 nm. A 40 Gbps data transmission experiment demonstrates the data transmission capabilities of the fabricated devices. The measured eye diagrams are clear and wide-open, and the bit error rate measurements show reasonable power penalties, indicating good device performance.

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In the refinery industry, especially in large-scale modern refineries, production scheduling modeling is an essential tool in the operation and management. By scheduling systems, better economic performance can be achieved. In order to implement the scheduling schemes, the influence of control systems has to be considered in scheduling models. This paper presents a novel refinery scheduling model where several controllable and realizable operation modes for production units are established based on unitwide predictive control. Furthermore, operational transitions resulting from switching operation modes of production units are taken into account to reflect the dynamic nature of production. A novel mixed integer linear programming (MILP) discrete-time model is developed, and computational tests show the efficiency of the proposed model.

In this letter, we propose a novel multiwavelength fiber laser based on fiber loop mirror formed by a highbirefringence fiber, a polarisation controller, and a 3 dB directional coupler. By setting the polarisation controller as half-waveplate, the fiber loop mirror acts as a polarisation-independent wavelength filter; Erbium-doped fiber (EDF) cooling by liquid nitrogen acts as gain medium. The wavelength spacing between the adjacent modes of the laser can be varied accurately by adjusting the length of the High-Birefringence (HiBi) fiber.