Construction and development of a new single-column simulated moving bed system on the laboratory scale

Simulated moving bed (SMB) chromatography combines high productivity and high purities with reduced buffer consumption. We have developed a laboratory scale single column SMB (SC-SMB) unit with all four separation zones in one column. Distributors embedded within the chromatographic medium allow introduction and withdrawal of liquid between the zones. This single column unit exhibits homogenous packing in all zones, reduced headspace, less complex tubing, fewer valves, and almost undisturbed plug flow between the separation zones. The separation performance of the column was investigated with two different binary model mixtures. Furthermore, the SC-SMB unit is operated with a modified AKTA Explorer workstation, which has been specifically developed for the handling of biological fluids.     

A comment on “Returns to scale and scale elasticity in data envelopment analysis”

Fukuyama [Fukuyama, H., 2000. Returns to scale and scale elasticity in data envelopment analysis. European Journal of Operational Research 125, 93–112] provided some characterizations of scale elasticity and returns to scale in DEA. In this paper, we present some counterexamples and comments to the main lemma of the afore-mentioned paper, based on which Fukuyama’s idea has been built.     

Two new homoisoflavanones from Polygonatum odoratum (Mill.) Druce

<正>Two new homoisoflavanones were isolated from the rhizomes of Polygonatum odoratum(Mill.) Druce and their structures were elucidated as(3R)-5,7-dihydroxy-8-methoxy-3-(4-methoxybenzyl)-6-methylchrom-an-4-one(1) and(3R)-5,7,8-trihydroxy-3-(4- hydroxybenzyl)-6-methylchroman-4-one(2),on the basis of spectral analysis.     

The characteristics of acoustic line array prototypes for scale model experiments

The sound fields created by three different settings of a 5 m long linear loudspeaker array were studied experimentally in the present investigation in an attempt to find out a method to produce a reasonable sound field for scaled down model experiments. The first setting was with all the loudspeakers facing vertically upward, while the second setting was with all the loudspeakers facing the horizontal. The last one resembled the first setting but the loudspeakers were put inside a small partial enclosure whose opening was facing vertically upward. Results show that the last setting can produce a sound field with characteristics close to those of a two-dimensional sound field. The second setting results in a sound directivity pattern relevant to that of the measured A-weighted traffic noise.     

多模跟踪技术在轮式侦察车图像处理器的应用

为解决目标旋转形变、遮挡、光照变化等目标跟踪的难题,对粒子滤波和尺度不变特征变换（SIFT）算法进行了改进,结合两种算法提出了决策主导模式的多模跟踪技术。该技术采用粒子滤波预测目标位置进行粗定位,SIFT特征匹配进行精定位的方法,在解决上述难题上有很好的鲁棒性。将该技术应用于轮式侦察车图像处理器,并进行了各种实验验证,结果证明了提出算法的有效性。     

Differences in Self-Rated, Perceived, and Acoustic Voice Qualities Between High- and Low-Fatigue Groups

Objectives

The present study was performed to examine which factors among self-rated scales, perceptual evaluations, and acoustic parameters, calculated from sustained vowels, are reliable indicators of physical and mental fatigues.

Methods

A total of 73 volunteers (male:female, 52:21), aged 19–24 years, were enrolled in this study. We defined the high- and low-fatigue groups using the Chalder Fatigue Scale score. For assessment of self-rated symptoms, each subject was asked to complete Voice Handicap Index (VHI) and Voice Rating Scale (VRS). For perceptual evaluations, three clinicians assessed each subject’s vocal quality on the Grade, Roughness, Breathiness, Asthenia, Strain Scale. For acoustic analysis, each subject was asked to produce sustained vowels /a/, /e/, /i/, /o/, and /u/ for 3 seconds. Then, the habitual fundamental frequency (F₀), jitter, shimmer, F₀ tremor, mean F₀, standard deviation of F₀, maximum F₀, minimum F₀, normalized noise energy, harmonic-to-noise ratio (HNR), signal-to-noise ratio (SNR), amplitude tremor, and ratio within 2–4 kHz were calculated using Dr. Speech software.

Results

In men, VHI, VRS, F₀ tremor, shimmer, HNR, SNR, and amplitude tremor were related to mental fatigue. In women, only VHI was related to physical fatigue, and none of the acoustic parameters was related to the fatigue score. Perceptual evaluations were not related to fatigue in men or women.

Conclusions

These findings suggest that self-rated symptoms and acoustic parameters related to voice quality are indicative of mental fatigue, and these features are prominent in men.     

Morphological and ultrastructural characterization of the alimentary canal in Japanese wax scale (Ceroplastes japonicus Green)

The morphology and ultrastructure of the alimentary canal in the adult female of the Japanese wax scale, Ceroplastes japonicus Green (Hemiptera: Coccoidea: Coccidae), was investigated using light microscopy, scanning electron microscopy and transmission electron microscopy. The results showed that the foregut was subdivided into a sclerotized pharynx and an oesophagus. A pair of salivary glands attached in the middle of the foregut. The loop-shaped midgut was narrow and longer than the foregut and its inner wall lined with a thick layer of epithelia. The hindgut was divided into a narrower ileum and a broader rectum, with the well-developed filter chamber enclosed in the anterior rectum. Malpighian tubules consisted of two brownish-yellow moniliform tubules with pores, approximately 1 μm in diameter, scattered on the outer surface and many spherical crystals inside the tubules.     

Stabilization via parametric excitation of multi-dof statically unstable systems

The problem of re-stabilization via parametric excitation of statically unstable linear Hamiltonian systems is addressed. An n-degree-of-freedom dynamical system is considered, at rest in a critical equilibrium position, possessing a pair of zero-eigenvalues and n − 1 pairs of distinct purely imaginary conjugate eigenvalues. The response of the system to a small static load, making the zero eigenvalues real and opposite, simultaneous to a harmonic parametric excitation of small amplitude, is studied by the Multiple Scale perturbation method, and the stability of the equilibrium position is investigated. Several cases of resonance between the excitation frequency and the natural non-zero frequencies are studied, calling for standard and non-standard applications of the method. It is found that the parametric excitation is able to re-stabilize the equilibrium for any value of the excitation frequencies, except for frequencies close to resonant values, provided a sufficiently large excitation amplitude is enforced. Results are compared with those provided by a purely numerical approach grounded on the Floquet theory.     

A scale model investigation of sound reflection from building façades

A simple model for predicting the sound reflected from a building façade is developed based upon the assumption that the scattering coefficient is small. This model is then used as the basis of an experimental attempt to measure the scattering properties of scale model façades featuring a similar degree of surface irregularity to that found on real buildings. A series of measurements made on a simple scale model are described and the effect of a non-uniform distribution of façade scattering is examined. The measured value of the scattering coefficient is found to be small and not very sensitive to the degree of surface irregularity. A progression of energy from a specular reflection field to a diffuse reflection field for successive orders of reflections is observed. It is suggested that the dominant mechanism of sound propagation for higher order reflections is via random scattering and that the development of propagation models based upon purely random scattering is a valid approach.