Two Spot Coupled Ring Resonators

Abstract. We consider a model of two coupled ring waveguides with constant linear gain and nonlinear absorption with space-dependent coupling. This system can be implemented in various physical situations as optical waveguides, atomic Bose-Einstein condensates, polarization condensates, etc. It is described by two coupled nonlinear Schrödinger equation. For numerical simulations, we take local two-gaussian coupling.It is found in our previous papers that, depending on the values of involved parameters, we can obtain several interesting nonlinear phenomena, which include spontaneous symmetry breaking, modulational instability leading to generation of stable circular flows with various vorticities, stable inhomogeneous states with interesting structure of currents flowing between rings, as well as dynamical regimes having signatures of chaotic behavior. This research will be associated with experimental investigation planned in Freie Universität Berlin, in the group of prof. Michael Giersig

Vortex flow generator utilizing synthetic jets by diaphragm vibration

This paper develops a millimeter scale fully packaged device in which a vortex flow of high velocity is generated inside a chamber. Under the actuation by a lead zirconate titanate (PZT) diaphragm, a flow circulates with increasing velocity after each actuating circle to form a vortex in a cavity named as the vortex chamber. At each cycle, the vibration of the PZT diaphragm creates a small net air flow through a rectifying nozzle, generates a synthetic jet which propagates by a gradual circulation toward the vortex chamber and then backward the feedback chamber. The design of such device is firstly conducted by a numerical analysis whose results are considered as the base of our experimental set-up. A vortex flow generated in the votex chamber was observed by a high-speed camera. The present approach which was illustrated by both the simulation and experiment is potential in various applications related to the inertial sensing, fluidic amplifier and micro/nano particle trapping and mixing

Economic Uncertainty and Tourism Consumption

This study examines the influence of economic uncertainty on tourism. The key hypothesis to test is that while economic uncertainty reduces outbound tourism, it may boost domestic tourism due to the economic-stagnant effects. Utilizing the framework of the theory of reasoned action to analyze a global sample of 124 countries over the period 1996–2017, we find some initial evidence showing that an increase in economic uncertainty encourages domestic tourism while reducing outbound tourism in the global sample. Notably, while these effects are consistent in the upper-middle-income economies, an increase in uncertainty has a positive impact on both domestic and outbound tourism in lower-middle-income economies and a negative impact on both domestic and outbound tourism in higher-income economies. The key implementation of this study is that tourism development is not always associated with economic development and stability; sometimes it could be a signal of economic stagnancy and inactiveness

New primitives of controlled elements F2/4 for block ciphers

This paper develops the cipher design approach based on the use of data-dependent operations (DDOs). A new class of DDO based on the advanced controlled elements (CEs) is introduced, which is proven well suited to hardware implementations for FPGA devices. To increase the hardware implementation efficiency of block ciphers, while using contemporary FPGA devices there is proposed an approach to synthesis of fast block ciphers, which uses the substitution-permutation network constructed on the basis of the controlled elements F2/4 implementing the 2 x 2 substitutions under control of the four-bit vector. There are proposed criteria for selecting elements F2/4 and results on investigating their main cryptographic properties. It is designed a new fast 128-bit block cipher MM-128 that uses the elements F2/4 as elementary building block. The cipher possesses higher performance and requires less hardware resources for its implementation on the bases of FPGA devices than the known block ciphers. There are presented result on differential analysis of the cipher MM-12

A study of ion wind generator using parallel arranged electrode configuration for centrifugal flow mixer

Ion wind is recently applied in various research areas such as the biomedical engineering, microfluidic mixing and particle manipulation. In this work, a bipolar ion wind generator configured by parallel arranged electrodes is used for centrifugal mixing applications. With the proposed configuration, negative and positive ion winds are simultaneously generated, mixed and then neutralized by each other while travelling toward liquid surface. The efficiency of the device was investigated both computationally and experimentally. The mixing of liquid occurred in different ways when the system is activated by either direct or alternating currents. Furthermore, the mixing is dependent on the dimension of electrode tip

Saprochaete Capitata Infection in an 80–Year Old Chronic Obstructive Pulmonary Disease (COPD) Patient: A Case Report

BACKGROUND: The fungal disease caused by invasive fungus Saprochaete capitata is becoming an increasingly popular infection. Fungal pathogens mainly occur in patients with immunocompromised disorders such as hematologic malignancies, acute myeloid leukemia, transplant patients. CASE REPORT: In this study, we presented a COPD patient infected with S. capitata. At the first check, the patient showed cough, dyspnea, chest pain on both sides. The clinical laboratory test result was characterized with high White blood cell (12.8 G/L), HIV negative. The X ray showed bronchitis and emphysema. Bronchoscopy illustrated bronchial mucositis. CT scanner demonstrated pneumonia with fuzzy nodular lesions and thick interstitial organization in both lungs. The patient was treated with ciprofloxacin 800 mg/day; cefuroxime 2250 mmg/day. However, the fever appeared 2 weeks thereafter. The S. capitata was discovered in the bronchial fluid. The patient was then treated with fluconazole 400 mg/day for 14 days. At the end of treatment, all signs and symptoms of S. capitata infection disappeared and the patient recovered. CONCLUSION: This case study showed that S. capitata infection can occur in the COPD patients and fluconazole is a pertinent drug for treatment of the infection