建筑空间光影设计及其视觉体验

光影设计是建筑空间设计的一项重要内容,它关系到室内空间形象的展示和观者的视觉心理体验。只有充分理解光影艺术构成的方法,才能创造出适合人们情感和心理的建筑空间。     

Some critical areas in robotics research

The general field of robotics is briefly reviewed. Two important areas—computer vision and compliance—are identified and discussed at some length. Some comparisons between the various approaches to the vision question are made, and active and passive force measurement are contrasted. Finally some other important areas including hierarchical control, manipulators, grippers and fixture are considered. It is concluded that significant developments in robotic technology, particularly as they apply to batch manufacturing, will be forthcoming in the near future.     

Augmented release of Teretrius nigrescens Lewis (Coleoptera: Histeridae) for the control of Prostephanus truncatus (Horn) (Coleoptera: Bostrichidae) in stored cassava chips

A trial was set up in northern Benin to evaluate the potential of Teretrius nigrescens to reduce the infestation and damage to cassava chips caused by storage insects. Cassava chips were stored for 5 months in mud silos and 50 adults of T. nigrescens were added when the stores were first filled. Stores where no predator was released were monitored as controls. The main storage insects observed were Prostephanus truncatus and Dinoderus spp. Initial chip weight varied between 102 and 246 g with no difference between treatments. Chip weight and number of holes on chips initially differed between treatments after 2 months of storage. After 3 months of storage, losses reached 40-50% without T. nigrescens and 30-40% when cassava chips were stored with T. nigrescens. A farmer can increase his profit by 1437 Fcfa/100 kg (1$=560 Fcfa, 1£=968 Fcfa; 1€=656 Fcfa, as on 2 December 2005) through the use of T. nigrescens because losses are reduced by 11%. Data analysis showed that there were significant differences (P<0.0001) between the two treatments for the number of holes, number of insects, weight of each chip as well as damage. There were twice as many P. truncatus and holes on chips in stores where T. nigrescens was not released. The addition of the predator to farmers’ stores is an economic option for controlling losses due to insects in cassava chips.     

自动控制脉冲强光杀菌装置的研制

采用单片机控制技术，研制了自动控制脉冲强度杀菌装置。每个光脉冲的输入能量可达６００～２２００Ｊ；光脉冲宽度经测定小于８００μＳ。３０个光脉冲能使大肠杆菌减少５个数量级，４０个光脉冲以使蛋白酶的活力钝化９０％，脉冲强光杀菌可事负透明塑料薄膜包装的切片面包的保存期延长１倍以上，脉冲强光杀菌是一种很有发展前途的冷杀菌技术。     

贯流式水轮发电机转子的电磁场和温度场计算分析

针对大型贯流式水轮发电机转子损耗发热难以全面监测的问题,建立了发电机二维场路耦合时步有限元模型和转子三维温度场有限元模型,考虑了电磁场时变、运动、非线性等因素对损耗的影响以及转子铁心各向异性导热性能和磁极迎风面、背风面散热性能差异对发热的影响.在此基础上,以1台36MW 贯流式水轮发电机为例,对其额定对称工况的转子损耗和温度分布规律进行了综合计算分析,并与实测数据进行了比较.结果表明,本文计算精度较高,其研究工作对探讨大型贯流式水轮发电机转子的损耗发热规律、提高其过热监测与保护水平,具有参考价值.     

单层吸波材料设计的一般方程及其可能解

研究了正入射条件下,金属基单层电磁波吸收材料设计中所遵循的一般 方程式,并给出了对应的最佳电磁参数和匹配厚度的可能解和理论设计曲线。     

Effect of exposure to light on physico-chemical quality attributes of sliced dry-cured Iberian ham under different packaging systems

Dry-cured Iberian ham slices were stored under vacuum and under two different atmospheres (N₂ = 70% N₂ + 30% CO₂; Ar = 70% Ar + 30% CO₂) and exposed to lightness or darkness. Physico-chemical, sensory and microbial analysis was carried out throughout 60 days storage. Vacuum samples showed the highest a*-value compared to N₂ and Ar after 30 (P < 0.05) and 60 days (P < 0.05). The influence of illumination during storage was evident after 60 days of storage, L* and a*-values being lower (P < 0.01) in hams exposed to light than those kept in darkness, which can be ascribed to the lower nitrosylmioglobin content in samples exposed to light after 60 days (P = 0.001). Ham slices stored in darkness showed the lowest TBARS values (P < 0.05) and hexanal content (P < 0.05) after 60 days. Slices of ham packed in vacuum showed lower TBARS values than N₂ and Ar batches (P = 0.001), these samples being perceived as more rancid (P < 0.05). The rest of the sensory attributes were not generally affected by gas mixture or illumination (P > 0.05).     

Simultaneous determination of tenderness and Escherichia coli contamination of pork using hyperspectral scattering technique

A rapid nondestructive method based on hyperspectral scattering technique for simultaneous determination of pork tenderness and Escherichia coli (E. coli) contamination was studied in the research. The hyperspectral scattering images of thirty-one pork samples were collected in 400-1100 nm, and the scattering profiles were then fitted by Lorentzian distribution function to give three parameters a (asymptotic value), b (peak value) and c (full width at b/2). The combined parameters of (b-a), (b-a) × c, (b-a)/c and “a&b&c” were used to develop multi-linear regression (MLR) models for prediction of pork tenderness and E. coli contamination. It was shown that MLR models developed using parameters a, b, (b-a) and (b-a)/c can give high correlation coefficients of 0.831, 0.860, 0.856 and 0.930 respectively for pork tenderness prediction. For E. coli contamination of pork, MLR models based on parameters a and “a&b&c” can give high R_CV of 0.877 and 0.841 respectively.     

Estimation of factors influencing fatty acid profiles in light lambs

Fatty acid composition of intramuscular, intermuscular, subcutaneous, omental and kidney knob fat depots of eighty male light lambs (±21 kg live weight) from five Spanish sheep breeds was analysed. Fat depot, anatomical depot location (internal, external and intramuscular), breed (Spanish Merino, Grazalema Merino, Churra Lebrijana, Segureña and Montesina), weaning type (weaning at 45 days after birth or no weaning) and subcutaneous fat thickness factors were analyzed using a statistical model to quantify their contribution to the variation of each fatty acid. Production system was the main factor to explain variations in overall fatty acid profiles (34.68%). However, for several fatty acids and indices (arachidonic, linoleic, PUFA, n − 3/n − 6) anatomical depot location was the most significant factor. Feeding system explained 65.49% of CLA variance, indicating a strong influence of suckling period length on CLA deposition in lambs’ fat. Moreover, due to the lack of interaction between anatomical depot location or depot and breed type or weaning system for total CLA, for future research only one depot would be enough to study the effect of those factors on CLA levels.     

LED lighting and seasonality effects antioxidant properties of baby leaf lettuce

We report on the application of supplementary light-emitting diode (LED) lighting within a greenhouse for cultivation of red, green and light green leaf baby lettuces (Lactuca sativa L.) grown under natural illumination and high-pressure sodium (HPS) lamps (16-h; PPFD-170 μmol m⁻² s⁻¹) during different growing season. Supplementary lighting from blue 455/470 nm and green 505/530 nm LEDs was applied (16-h; PPFD-30 μmol m⁻² s⁻¹). Our results showed that to achieve solely a positive effect is complicated, because metabolism of antioxidant properties in lettuce depended on multicomponent exposure of variety, light quality or seasonality. The general trend of a greater positive effect of supplemental LED components on the vitamin C and tocopherol contents was in order: 535 > 505 > 455 > 470 nm; on the total phenol content: 505 > 535 = 470 > 455 nm; on the DPPH free-radical scavenging capacity: 535 = 470 > 505 > 455 nm; on the total anthocyanins: 505 > 455 > 470 > 535 nm. Further investigations are needed for understanding the mechanism and interaction between antioxidants and light signal transduction pathways.