FREEZE DRYING CHARACTERISTICS OF MEDICINAL HERBS

The demand on traditional herb medicine shows a tremendous increase. Conventionally, medicinal herbs are dried at high temperatures, causing quality deterioration. The freeze-drying characteristics of medicinal herbs were studied, and the quality of the freeze-dried products assessed. The herbs studied were medicinal ginger and Javanese pepper.

It was found that drying time, was more influenced by chamber pressure and freezing rate than by the surface temperature of the product. Higher chamber pressures and faster freezing rates tended to shorten the initial (primary) drying time but lengthen the secondary drying time. Quality of the freeze-dried product was assessed as slightly lower than the quality of the raw material, but higher than when oven dried at 35-40°C, and met the MMI standard.     

Quasi-one-dimensional photonic crystal as a compact building-block for refractometric optical sensors

We report the fabrication and the characterization of the refractometric and thermo-optical properties of a quasi-one-dimensional waveguide photonic crystal-a strong, 76-/spl mu/m-long Bragg grating. The transmission spectra (around 660 nm) of the structure have been measured as a function of both the cladding refractive index and the temperature. The transmission stopband was found to shift by 0.8-nm wavelength for either a cladding refractive index change of 0.05 or a temperature change of 120 K. The steep stopband edges provide a sensitive detection method for this band shift, by monitoring the transmitted output power.     

Goal-driven risk assessment in requirements engineering

Risk analysis is traditionally considered a critical activity for the whole software system’s lifecycle. Risks are identified by considering technical aspects (e.g., failures of the system, unavailability of services, etc.) and handled by suitable countermeasures through a refined design. This, however, introduces the problem of reconsidering system requirements. In this paper, we propose a goal-oriented approach for analyzing risks during the requirements analysis phase. Risks are analyzed along with stakeholder interests, and then countermeasures are identified and introduced as part of the system’s requirements. This work extends the Tropos goal modeling formal framework proposing new concepts, qualitative reasoning techniques, and methodological procedures. The approach is based on a conceptual framework composed of three main layers: assets, events, and treatments. We use “loan origination process” case study to illustrate the proposal, and we present and discuss experimental results obtained from the case study.     

UV Direct Write Metal Enhanced Redox (MER) Domain Engineering for Realization of Surface Acoustic Devices on Lithium Niobate

A new and highly versatile domain patterning method—ultraviolet direct write metal enhanced redox (UV direct write MER)—achieves deep domains with practically no thermally‐induced damage on the surface of lithium niobate crystals. In UV direct write MER, after coating with a thin layer of chromium, the domain inversion is generated by a redox process induced in the crystal by illumination with high intensity UV in an ambient dry nitrogen atmosphere. This new technique enables the fabrication of practical piezoelectric acoustic superlattice structures on 128° YX‐cut LiNbO₃, the most widely used crystal cut for surface acoustic wave applications. For example, UV direct write MER was used to form an acoustic superlattice 128° YX structure that in turn enabled the generation of surface acoustic waves of sufficient strength to develop fluid flow within a droplet of water, demonstrating its potential in practical microfluidic manipulation. This is the first demonstration of a UV direct write surface acoustic wave transducer reported to date, made possible only due to the unique qualities of the MER domain engineering process.     

Weakly-Supervised Action Localization,and Action Recognition Using Global–Local Attention of 3D CNN

International Journal of Computer Vision - 3D convolutional neural network (3D CNN) captures spatial and temporal information on 3D data such as video sequences. However, due to the convolution and...     

Fabrication and characterization of high-quality uniform and apodized Si/sub 3/N/sub 4/ waveguide gratings using laser interference lithography

A method is presented for fabricating high-quality ridge waveguide gratings by combining conventional mask lithography with laser interference lithography. The method, which allows for apodization functions modulating both amplitude and phase of the grating is demonstrated by fabricating a grating that is chirped by width-variation of the grated ridge waveguide. The structure was optically characterized using both an end-fire and an infrared camera setup to measure the transmission and to map and quantify the power scattered out of the grating, respectively. For a uniform grating, we found a Q value of /spl sim/8000 for the resonance peak near the lower wavelength band edge, which was almost completely suppressed after apodization.