975 resultados para RGB color pattern


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Personal electronic devices, such as cell phones and tablets, continue to decrease in size while the number of features and add-ons keep increasing. One particular feature of great interest is an integrated projector system. Laser pico-projectors have been considered, but the technology has not been developed enough to warrant integration. With new advancements in diode technology and MEMS devices, laser-based projection is currently being advanced for pico-projectors. A primary problem encountered when using a pico-projector is coherent interference known as speckle. Laser speckle can lead to eye irritation and headaches after prolonged viewing. Diffractive optical elements known as diffusers have been examined as a means to lower speckle contrast. Diffusers are often rotated to achieve temporal averaging of the spatial phase pattern provided by diffuser surface. While diffusers are unable to completely eliminate speckle, they can be utilized to decrease the resultant contrast to provide a more visually acceptable image. This dissertation measures the reduction in speckle contrast achievable through the use of diffractive diffusers. A theoretical Fourier optics model is used to provide the diffuser’s stationary and in-motion performance in terms of the resultant contrast level. Contrast measurements of two diffractive diffusers are calculated theoretically and compared with experimental results. In addition, a novel binary diffuser design based on Hadamard matrices will be presented. Using two static in-line Hadamard diffusers eliminates the need for rotation or vibration of the diffuser for temporal averaging. Two Hadamard diffusers were fabricated and contrast values were subsequently measured, showing good agreement with theory and simulated values. Monochromatic speckle contrast values of 0.40 were achieved using the Hadamard diffusers. Finally, color laser projection devices require the use of red, green, and blue laser sources; therefore, using a monochromatic diffractive diffuser may not optimal for color speckle contrast reduction. A simulation of the Hadamard diffusers is conducted to determine the optimum spacing between the two diffusers for polychromatic speckle reduction. Experimental measured results are presented using the optimal spacing of Hadamard diffusers for RGB color speckle reduction, showing 60% reduction in contrast.

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Purpose: Computer vision has been widely used in the inspection of electronic components. This paper proposes a computer vision system for the automatic detection, localisation, and segmentation of solder joints on Printed Circuit Boards (PCBs) under different illumination conditions. Design/methodology/approach: An illumination normalization approach is applied to an image, which can effectively and efficiently eliminate the effect of uneven illumination while keeping the properties of the processed image the same as in the corresponding image under normal lighting conditions. Consequently special lighting and instrumental setup can be reduced in order to detect solder joints. These normalised images are insensitive to illumination variations and are used for the subsequent solder joint detection stages. In the segmentation approach, the PCB image is transformed from an RGB color space to a YIQ color space for the effective detection of solder joints from the background. Findings: The segmentation results show that the proposed approach improves the performance significantly for images under varying illumination conditions. Research limitations/implications: This paper proposes a front-end system for the automatic detection, localisation, and segmentation of solder joint defects. Further research is required to complete the full system including the classification of solder joint defects. Practical implications: The methodology presented in this paper can be an effective method to reduce cost and improve quality in production of PCBs in the manufacturing industry. Originality/value: This research proposes the automatic location, identification and segmentation of solder joints under different illumination conditions.

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Features of the valid nominal species of Aprionodon Gill (isodon Valenciennes) and Hypoprion Muller and Henle (hemiodon Valenciennes, macloti Muller and Henle, and signatus Poey), plus those of a previously unrecognized species here described as Carcharhinus leiodon n.sp., are examined and compared with those of Carcharhinus Blainville. Features studied include morphometrics, vertebral numbers and other vertebral characteristics, tooth numbers, color pattern, and some other aspects of external morphology. It is concluded that on these features C. leiodon n.sp. is entirely encompassed within the parameters of Carcharhinus, and that, although A. isodon, H. hemiodon, H. macloti, and H. signatus each extend the range of diversity of Carcharhinus in one or more features, A. isodon is not uniquely different from Carcharhinus, and there is no common pattern of difference between the three species of Hypoprion and Carcharhinus. Accordingly, and because the nature of the teeth of Aprionodon and Hypoprion has been found insufficient to warrant generic distinction from Carcharhinus, the genera Aprionodon and Hypoprion are synonymised with Carcharhinus. A diagnosis and description are given for each of the above species. The descriptions include measurements, counts, and line illustrations that show the whole shark in lateral view, underside of head, nostril, and teeth. The geographic distribution is summarized, as are also the meager biological data available on number of embryos, size at birth, size at sexual maturity, and maximum size. (PDF file contains 32 pages.)

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As doenças cardiovasculares possuem a maior taxa de óbitos no mundo, e notavelmente nos últimos anos as pesquisas genéticas sobre as mesmas estão baseadas em estudos de associação, no qual o gene suspeito que esteja em maior frequência entre os pacientes passa a ser considerado um possível fator causal. Os polimorfismos genéticos que ocorrem no receptor beta-adrenérgico podem resultar em mudanças significativas na função do receptor, podendo acarretar fisiopatologias. Neste trabalho, o objetivo foi estimar a diversidade e a frequência do polimorfismo Ser49Gly do gene do receptor beta-adrenérgico 1 a partir de uma amostra de 188 indivíduos da população do Estado do Rio de Janeiro. As frequências também foram analisadas a partir da estratificação da amostra por critério fenotípico em função do padrão de cor da pele em (negros e não negros) ou ancestralidade genética em (afrodescendente e não afrodescendente), definida através da informação dos marcadores de ancestralidade Indels e SNP de cromossomo Y, para avaliar se os padrões de ancestralidade ou cor da pele são fundamentais para a diferenciação e distanciamento genético. Fragmentos de interesse foram amplificados por PCR (reação de cadeia de polimerase) com primers específicos para o marcador Ser49Gly e as reações de genotipagem foram realizadas com enzimas de restrição Eco0109I. Os valores da heterozigosidade variaram entre 0,25-0,50 e 0,20-0,41 nos grupos estratificados por ancestralidade e cor da pele, respectivamente. No que diz respeito à análise do equilíbrio de Hardy-Weinberg, não houve um desvio significativo na distribuição do marcador nas amostras gerais do Estado do Rio de Janeiro, ou mesmo nas amostras estratificadas. A distribuição dos alelos na amostra dos 188 indivíduos da população geral do Rio de Janeiro (AC_RJ) mostrou uma frequência de 80,30% e 19,70% para o alelo selvagem e mutado Ser49Gly, respectivamente. A comparação das análises sobre a distribuição das frequências alélicas para este marcador mostrou a ocorrência de diferenças significativas na distribuição das frequências alélicas entre negros e não negros e afrodescendentes e não afrodescendentes. A diferença significativa observada entre os negros e afrodescendentes, foi em menor grau de distanciamento. A informação obtida em relação à ancestralidade foi crucial para a obtenção dos dados sobre o aumento da variável mutada do polimorfismo Ser49Gly nas populações negras e afrodescendentes do Estado Rio de Janeiro. Tal evidência, em combinação com estudos clínicos podem contribuir para uma análise pormenorizada do padrão de susceptibilidade à doença em questão, em falhas do mecanismo deste receptor.

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Age-based analyses were used to demonstrate consistent differences in growth between populations of Acanthochromis polyacanthus (Pomacentridae) collected at three distance strata across the continental shelf (inner, mid-, and outer shelf) of the central Great Barrier Reef (three reefs per distance stratum). Fish had significantly greater maximum lengths with increasing distance from shore, but fish from all distances reached approximately the same maximum age, indicating that growth is more rapid for fish found on outer-shelf reefs. Only one fish collected from inner-shelf reefs reached >100 mm SL, whereas 38−67% of fish collected from the outer shelf were >100 mm SL. The largest age class of adult-size fish collected from inner and mid-shelf locations comprised 3−4 year-olds, but shifted to 2-year-olds on outer-shelf reefs. Mortality schedules (Z and S) were similar irrespective of shelf position (inner shelf: 0.51 and 60.0%; mid-shelf: 0.48 and 61.8%; outer shelf: 0.43 and 65.1%, respectively). Age validation of captive fish indicated that growth increments are deposited annually, between the end of winter and early spring. The observed cross-shelf patterns in adult sizes and growth were unlikely to be a result of genetic differences between sample populations because all fish collected showed the same color pattern. It is likely that cross-shelf variation in quality and quantity of food, as well as in turbidity, are factors that contribute to the observed patterns of growth. Similar patterns of cross-shelf mortality indicate that predation rates varied little across the shelf. Our study cautions against pooling demographic parameters on broad spatial scales without consideration of the potential for cross-shelf variabil

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We provide morphological and molecular evidence to recognize a new species of skate from the North Pacific, Bathyraja panthera. We also resurrect the skate subgenus Arctoraja Ishiyama, confirming its monophyly and the validity of the subgenus. Arctoraja was previously recognized as a distinct subgenus of Breviraja and later synonymized with Bathyraja (family Rajidae). Although the nominal species of Arctoraja have all been considered synonyms of Bathyraja parmifera by various authors, on the basis of morphometric, meristic, chondrological, and molecular data we recognize four species, including the new species. Species of Arctoraja are distributed across the North Pacific Ocean and adjacent seas from southern Japan to British Columbia. Bathyraja parmifera is abundant in the eastern Bering Sea, Aleutian Islands, and northern Gulf of Alaska; B. smirnovi is a western Pacific species found in the Sea of Okhotsk and Sea of Japan; B. simoterus is restricted to waters around the northern and eastern coasts of Hokkaido, Japan; and the new species B. panthera is restricted to the western Aleutian Islands. Bathyraja panthera is diagnosed by its color pattern of light yellow blotches with black spotting on a greenish brown background, high thorn and vertebral counts, chondrological characters of the neurocranium and clasper, and a unique nucleotide sequence within the mitochondrial cytochrome oxidase gene. Furthermore, the species presently recognized as Bathyraja parmifera exhibits two haplotypes among specimens from Alaska, suggesting the possibility of a second, cryptic species.

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We estimated the total number of pantropical spotted dolphin (Stenella attenuata) mothers killed without their calves (“calf deficit”) in all tuna purse-seine sets from 1973– 90 and 1996–2000 in the eastern tropical Pacific. Estimates were based on a tally of the mothers killed as reported by color pattern and gender, several color-pattern-based frequency tables, and a weaning model. Over the time series, there was a decrease in the calf deficit from approximately 2800 for the western-southern stock and 5000 in the northeastern stock to about 60 missing calves per year. The mean deficit per set decreased from approximately 1.5 missing calves per set in the mid-1970s to 0.01 per set in the late-1990s. Over the time series examined, from 75% to 95% of the lactating females killed were killed without a calf. Under the assumption that these orphaned calves did not survive without their mothers, this calf deficit represents an approximately 14% increase in the reported kill of calves, which is relatively constant across the years examined. Because the calf deficit as we have defined it is based on the kill of mothers, the total number of missing calves that we estimate is potentially an underestimate of the actual number killed. Further research on the mechanism by which separation of mother and calf occurs is required to obtain better estimates of the unobserved kill of dolphin calves in this fishery.

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红毛菜(Bangia Lyngb.)属于红藻门,与紫菜属同属红毛菜科,其味道和营养都优于紫菜。目前红毛菜栽培产业已在我国福建莆田展开,但栽培技术还有待提高。海藻栽培技术的发展和成熟依赖于对其生长发育过程的认识。本研究针对红毛菜发育过程及相关光合生理展开,并初步探讨了一采自山西娘子关泉淡水红毛菜群体(FWB)的系统地位。 色素突变标记的壳孢子萌发特征表明最初两次分裂产生的4细胞决定了完整植株的形态建成。成熟植株,为雌雄异体。雌性生殖器果胞的标志性分化结构为原始受精丝,环境因子是促发原始受精丝发展的外部因素,其膨大程度随受精的延迟而增大。原孢子是主要的无性生殖孢子类型,在不良环境中,藻体也会形成内生孢子或休眠包囊,或者藻体断裂后重新形成完整的植株。 红毛菜的生长发育很大程度上受环境因子的控制。高温不利于配子体的发育,15-20 ºC比较适宜。红毛菜无性繁殖的最适温度-光照组合为20 ºC-8 h,有性繁殖为15 ºC-12h。 不同发育阶段,PSII实际光合效率(Y(II))与细胞的健康状况以及光合器官完整性及其在细胞内的分布有关,而与细胞的类型关系不大。健康的假根细胞、已分化未成熟的精子以及果孢子细胞均具有很高的Y(II)。色素体由中间位变为围周位,中央大液泡(营养藻丝)和大小纤维囊泡(成熟孢子与精子)的产生,使得细胞Y(II)降低。刚放散的壳孢子Y(II)很低,说明在壳孢子由贝壳基质释放到自由水体过程,光合作用受到一定程度抑制;而2h后,Y(II)开始恢复,rbcL的转录水平非常高,为孢子的萌发储备物质和能量需求。 在失水和低盐胁迫下,藻体均维持较高的Y(II)。干出处理至藻体重量不再变化,复水后Y(II)可回复初始水平。海生红毛菜在100%淡水培养基中(约20ºC)培养7天后,部分雄性藻体依然活着。从而体现了红毛菜位居高潮带的生理优势。 FWB终生行无性繁殖,藻体形态与发生以及染色体数目(4条)与海生群体没有区别。而rbcL-rbcS Spacer序列显示,红毛菜海生群体(无性和有性)具有完全相同的序列,而FWB与它们有5bp差异,但是与欧洲、北美地区的淡水群体仅1bp不同,初步说明所有淡水红毛菜群体具有共同的原始起源。

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We describe a new species of gerreid fish, Gerres septemfasciatus, based on four specimens collected from the northern South China Sea. G septemfasciatus most closely resembles G limbatus in general appearance. However, G. septemfasciatus is distinguished from the latter and other congeners by having 3 to 3.5 scales between the base of. the fifth dorsal spine and lateral line. This species has a distinctive color pattern, including 7-8 regular, vertical, blue-grayish bands on its side. The distribution of this species is currently known to include the Chinese coastal waters of the South China Sea, but may be also include the coastal waters of southeastern Asia.

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This paper reports the occurrence of a marine brachyuran crab species Eucrate alcocki SerSne, in SerSne et al., 1973, of the family Euryplacidae Stimpson, 1871, for first time from India, based on a male specimen from Parangipettai fish landing centre in Bay of Bengal, Southeast Coast of India. Although morphologically corresponding with what is currently defined as E. alcocki, the color pattern of the carapace of the present specimen is rather different from that of the Chinese material-only the anterior fifth of the carapace is marked with scattered red spots, the rest of the surface is yellowish, with four unusually shaped red blotches which almost look like Sanskrit characters.

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The use of an acid violet 7 (AV7) smart ink to assess the activity of photocatalytic paint is demonstrated. A linear correlation is established between the change in oxidized dye concentration, as measured by diffuse reflectance, and the change in the green component of the RGB color values, obtained using a portable hand-held scanner, suggesting that such tests can be monitored easily using an inexpensive piece of hand-held office equipment, as opposed to an expensive lab-based instrument, such as a diffuse reflectance UV/vis spectrophotometer. The bleaching of the AV7 follows first order kinetics, at a rate that is linearly dependent upon the UVA irradiance (0.30–3.26 mW cm–2). A comparison of relative rate of bleaching of the AV7 ink with the relative rate of removal of NOx, as determined using the ISO test (ISO 22197-1:2007), established a linear relationship between the two sets of results and the relevance of this correlation is discussed briefly.

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Two new species of Cnemidophorus are described from the right bank of the Sao Francisco river, in the northwestern part of state of Bahia, Brazil. Both species are assigned to the Cnemidophorus ocellifer group and are distinguished from all other congeners on the basis of lepidosis and color pattern. One of them, Cnemidophorus cyanurus, shares with the species of the subgroup of C. littoralis (C. abaetensis, C. littoralis and C. venetacaudus), a bluish green tail, spurs on the heels of males, 6-7 supraciliaries, a high number of femoral pores (27-45), a row of enlarged scales in the dorsal part of the humerus, and 8 to 10 rows of ventral scales. The second species, Cnemidophorus nigrigula, shares with the C. ocellifer subgroup (composed of C. ocellifer, C. mumbuca, C. jalapensis and C. confusionibus) a low number of femoral pores (1421), enlarged scales in the temporal region posterior to the third subocular, 5 supraciliaries, 6 to 8 rows of ventral scales, and a brown tail color. It is also characterized by males being conspicuously larger than females and by females retaining the juvenile color pattern, which is lost in adult males. The latter characteristic has not been reported in any species of the C. ocellifer group before now. The two new species occur sympatrically at Santo Inacio.

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A new species of gekkonid lizard genus Gymnodactylus Spix, 1825 is described on the basis of material collected in the ""campos rupestres"" (open rocky communities) of Mucuge municipality, northeastern Brazil. G. vanzolinii sp. nov. differs from its congeners in the number of transverse and longitudinal rows of dorsal tubercles and color pattern. It is thought to be closer to G. guttulatus which also occurs and is restricted to the rocky communities from highland open areas in the Espinhaco mountain range. The discovery leads to a reevaluation of the taxonomic status of G. carvalhoi Vanzolini, 2005, which is here considered a synonym of G. amarali Barbour, 1925.

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Two syntopic species of Cnemidophorus are described from the Caatingas of the Parque Nacional da Serra das Confusoes (PNSC), located in the Southwestern region of the state of Piaui in Brazil. Both species are assigned to the ocellifer group, differing from all other members of the group by their distinct color pattern and lepidosis. Besides these differences, both new species share a number of particular features with other members of the group. One of them, C. venetacaudus, shares with C. abaetensis and C. littoralis the presence of spurs in the heels of males, six supraciliar scales, a high number of femoral pores (from 21-45), a row of enlarged scales in the dorsal region of the arm, 8-10 rows of ventral scales, and a bright bluish-green tail, while the other species, C. confusionibus, shares with C. ocellifer, C. mumbuca, and C. jalapensis a low number of femoral pores, enlarged scales in the temporal region (posterior to third subocular), 5 supraciliar scales, and 6-8 rows of ventral scales. Based on these comparisons, we suggest that the ocellifer group is more complex than previously admitted, being composed by at least two morphologically recognizable species subgroups.

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A new species of the genus Acratosaura is described on the basis of two specimens obtained at the ""campos rupestres"" (rocky meadows) near Mucuge municipality, state of Bahia, Brazil. Acratosaura spinosa sp. nov., has ear openings and eyelids, pentadactyl limbs lacking a claw on first toe, a single frontonasal, prefrontals, frontoparietals, parietals, interparietals, occipitals, no collar fold, three pairs of genials, three supraoculars and three superciliaries and is further characterized by presenting 28-31 rows of strongly keeled, lanceolate and imbricate dorsal scales, sides of the neck with keeled scales, striate temporal scales, four longitudinal and 17-18 transverse rows of smooth ventral scales, 28-30 scales around the body, 14 and 19-20 infradigital lamellae under finger IV and toe IV, respectively, 13 total preanal and femoral pores in male, absent in female. The new species differs strikingly in color pattern from its only congener A. mentalis. The two species occur sympatricaly in the high altitude open habitats near the type locality.