Pattern Of Vertical Stripes Research Articles

Influence of polarized light, disruptive visual patterns, and chemical cues on oviposition in the aquatic midge, Chironomus riparius (Diptera: Chironomidae).

Chironomid nonbiting midges are common in many waterbodies, occurring at high densities in sediment and also when flying adults emerge. Although important for food webs and ecosystem processes, the mass emergences of chironomid adults make some species nuisance pests. As part of an effort to develop "push-pull" strategies for managing midge populations, we investigated the importance of visual and chemical cues used by gravid females when selecting sites for oviposition. Field and laboratory oviposition choice tests with Chironomus riparius (Meigen) were used to assess the attractiveness of dark container colors and polarized light for females seeking water for egg laying. Females were not sensitive to increased intensity of polarized light, but they laid fewer eggs in containers with white color above the water's edge but black below the surface. A disruptive pattern of vertical black and white stripes at the water's edge reduced egg laying to a similar degree as white. To investigate the importance of olfactory or gustatory cues in oviposition decisions, we tested 3 potential chemical repellents (damaged larvae simulating predator presence, azadiractin, and picaridin) and 5 potential attractants (a tannin-molasses mixture, leaf detritus, live Hydrilla plants, periphyton, and fermented alfalfa infusions used to bait mosquito oviposition traps). Chemical cues appeared to play a weak role, if any, in oviposition choices. Onlyazadiractin (0.02 and 0.11 ppm) reduced the number of egg ropes deposited, but the mechanism may have been from mechanical trapping and drowning, not deterrence.

Model-Independent Lens Distortion Correction Based on Sub-Pixel Phase Encoding.

Lens distortion can introduce deviations in visual measurement and positioning. The distortion can be minimized by optimizing the lens and selecting high-quality optical glass, but it cannot be completely eliminated. Most existing correction methods are based on accurate distortion models and stable image characteristics. However, the distortion is usually a mixture of the radial distortion and the tangential distortion of the lens group, which makes it difficult for the mathematical model to accurately fit the non-uniform distortion. This paper proposes a new model-independent lens complex distortion correction method. Taking the horizontal and vertical stripe pattern as the calibration target, the sub-pixel value distribution visualizes the image distortion, and the correction parameters are directly obtained from the pixel distribution. A quantitative evaluation method suitable for model-independent methods is proposed. The method only calculates the error based on the characteristic points of the corrected picture itself. Experiments show that this method can accurately correct distortion with only 8 pictures, with an error of 0.39 pixels, which provides a simple method for complex lens distortion correction.

Evaluation of structural aspects and operation environments on the performance of passive micro direct methanol fuel cell

Passive micro direct methanol fuel cell (μDMFC) which operates based on fuel diffusion is preferred for portable applications for its structural simplicity. In this work, we have systematically investigated multiple variables including the hot-press conditions, current collector channel patterns, current collector open ratios, and their effects on the performance for passive μDMFC by experiments and simulations. Results indicate that vertical stripe pattern (VSP) is preferred for both anodes and cathodes due to the upward reaction products drift by natural convection. Open ratio of 45.6% and 35.8% are found to yield the best performance for anode and cathode, respectively. In addition, the external environmental conditions of vibration frequency, cell orientation, environmental temperature and atmospheric pressure are all discussed in detail in this work. The optimized fabrication, assembly and operation parameters shed light on the design considerations necessary for the wide adaptation of high-performance and durable passive μDMFC for portable applications.

Body size illusion by vertical and horizontal stripe patterns of clothes

縦縞が横縞よりも横幅が長く知覚される錯視をヘルムホルツ錯視と呼ぶ。一方で，ファッション業界では，縦縞模様は横縞模様よりも横幅が細く，身長が高く見えるとされ，逆の錯視が主張されている。本研究1では 3D人体モデルを用いて，服装の縞模様による体型錯視効果を，縞の向き（縦，横），duty比（0.1，0.5），太さ（4水準）の要因を操作し，階段法のアルゴリズムに基づいて測定した。参加者は20名の大学生であった。標準刺激は日本人女性の 3D平均体型CGモデルが白と黒の縞模様のワンピースを着用した画像であった。比較刺激はグレーの全身タイツを着用したCGモデルであり，平均体型からスリーサイズが±10 cmの範囲で 2 cmずつ変化した11段階の刺激を用いた。参加者の課題は左右に並んで提示されたモデルのうち，より太って見える方を選ぶことであった。その結果，縦縞ではduty比0.5のほうが0.1より細く知覚された。duty比0.5の時のみ横縞より縦縞のほうが細く知覚された。しかも，縦縞でも横縞でも縞が細くなるほど体型が細く知覚されていた。さらに研究2では縦縞・横縞の服が身長の知覚に及ぼす錯視効果も検討した。

Contrast sensitivity and visual acuity of Queensland fruit flies (Bactrocera tryoni).

This study examines the visual acuity of Queensland fruit flies (Bactrocera tryoni) by analysing their turning responses to an immersive visual stimulus consisting of a pattern of vertical stripes presented at various angular periods and rotational rates. The results infer that these flies possess an interommatidial angle of approximately [Formula: see text], and an ommatidial acceptance angle of approximately [Formula: see text]. This suggests that the visual acuity of Queensland fruit flies is substantially better than that of the classical vinegar fly (Drosophila melanogaster), and is comparable to those of the housefly (Musca domestica) and the honeybee (Apis mellifera). The contrast sensitivity of Queensland fruit flies is comparable to that of the housefly.

Feature enhancement for a defocusing structured-light 3-D scanning system

Structured-light systems consisting of a camera and projector are powerful and cost-effective tools for three-dimensional (3-D) shape measurements. However, most commercial projectors are unable to generate distinct patterns due to defocusing and shallow focusing issues. We propose a hybrid method for enhancing the calibration and scanning features of the defocusing structured-light 3-D scanning system. Instead of using conventional sequential binary patterns, we replace the highest-level binary pattern by a high-order sinusoidal pattern. In our proposed system, a pan-tilt stage carrying a checkerboard is used to assist the simultaneous calibration of the camera and projector. Initially, the camera is calibrated to obtain the extrinsic positions of the stage. In addition, we utilize the multiplication of vertical and horizontal stripe patterns to enhance the corresponding features between the camera and projector. The projector is then calibrated using the extrinsic features determined from the calibrated camera. The experimental results show that the use of the high-order sinusoidal pattern significantly improves reprojection error. Our proposed method can easily be incorporated in the defocusing projector for scanning various types of objects.

インテリアにおける壁紙模様が空間の知覚に及ぼす影響

This study was conducted to evaluate the effects of wallpaper pattern type, Munsell value, and illuminance on the perception of interior space. A series of psychological experiments were conducted to evaluate the four parameters: magnitude values of volume, width, depth, and height of interior space, using two types of one-tenth scale models of a room. The “horizontal model” measured 24 mc in height and 45 cm in width and depth, the “vertical model, ” measured 45 cm in height, 24 cm in width, and 45 cm in depth. The wallpaper patterns used in these experiments were vertical stripe, horizontal stripe, square, wave, floral and arabesque. The figures of the patterns were printed in three achromatic colours, N8.5, N7, and N5. The ground of the patterns and the floor were printed in achromatic colour N9. The walls and floor of a reference model with no pattern were also printed in N9. The experiments were conducted in three illuminance conditions: 750 lx, 500 lx, and 300 lx. A magnitude estimation method was applied to evaluate the four parameters. The eighteen subjects (12 women and 6 men) were asked to look into each model by turns through a viewing aperture in the rear wall and to compare their four spatial parameters of the comparison model with those of the standard model. These experiments were conducted separately with horizontal and vertical models. The results showed that the effects of the wallpaper pattern type, Munsell value, and illuminance were obvious. However, these effects were different between horizontal and vertical models and were more remarkable in horizontal model. It is because vertical model was so extraordinary that the effects of wallpaper pattern type and Munsell value became blurred. On the other hand, some of the effects were common between horizontal and vertical models, and can be regarded as stable results. These results can be summarized as follows: · The existence of wallpaper pattern decreased the magnitude value of volume. · The effects of the Munsell value were obvious;, the lower the Munsell value, the lower the magnitude values of volume, width, and depth. · The effects of the pattern type were different between horizontal model and vertical model. The pattern type had similar effects on the magnitude values of volume and depth of horizontal model. The horizontal stripe and floral patterns had higher corresponding value than did other types. The vertical stripe and horizontal stripe patterns had opposite effects on the magnitude values of width and height of both models. The horizontal stripe pattern increased the magnitude value of width and decreased that of height, whereas the horizontal stripe pattern increased the magnitude value of height and decreased that of width. · Illuminance was found to affect only the magnitude value of volume of horizontal model; the lower the illuminance, the lower the magnitude value of volume.

Apistogramma sororcula, a new dwarf cichlid (Teleostei: Cichlidae) from the drainage of the rio Guaporé in Bolivia and Brazil

Apistogramma sororcula sp. n. is described from the drainage of the the rio Guaporé in Bolivia (Departamento Beni) and Brazil (Estado Mato Grosso). It can be distinguished from all the other described Apistogramma species by the following combination of characters of the males: upper pectoral spot present, chin with dark band just below lower lip, a suborbital stripe becoming ventrally much wider, on bases of anterior abdominal scales several short vertical streaks forming oblique stripes, small round caudal spot, lateral band reaching caudal fin or caudal spot, produced dorsal-fin lappets, truncate caudal fin with streamers and distinct pattern of narrow vertical stripes, filamentous extensions of the pelvic fins and only three infraorbital pores. It is most similar to Apistogramma staecki Koslowski, 1985, but differs from this species by the higher number of 10 to 12 vertical stripes on the caudal fin of adult males, a lateral band reaching caudal fin or caudal spot, short vertical abdominal stripes on bases of scales of the anterior body and produced dorsal-fin lappets.

Controlled Topological Transitions in Thin-Film Phase Separation

In this paper the evolution of a binary mixture in a thin-film geometry with a wall at the top and bottom is considered. By bringing the mixture into its miscibility gap so that no spinodal decomposition occurs in the bulk, a slight energetic bias of the walls toward each one of the constituents ensures the nucleation of thin boundary layers that grow until the constituents have moved into one of the two layers. These layers are separated by an interfacial region where the composition changes rapidly. Conditions that ensure the separation into two layers with a thin interfacial region are investigated based on a phase-field model. Using matched asymptotic expansions a corresponding sharp-interface problem for the location of the interface is established. It is then argued that this newly created two-layer system is not at its energetic minimum but destabilizes into a controlled self-replicating pattern of trapezoidal vertical stripes by minimizing the interfacial energy between the phases while conserving their area. A quantitative analysis of this mechanism is carried out via a thin-film model for the free interfaces, which is derived asymptotically from the sharp-interface model.

Optic flow and sea-land orientation in the sandhopper Talitrus saltator.

The problem sandhoppers face when they find themselves on the dry sand is to reach as quickly as possible the belt of moist sand near the water. In the present study, I ask whether, alongside many other orienting factors, sandhoppers use the optic flow they experience to maintain their bearing relative to the sea-land axis. Adult individuals of Talitrus saltator were released in a transparent Plexiglas bowl, horizontally placed between four walls with a pattern of vertical black and white stripes. The orientation of one pair of opposite walls was south-north, orthogonal to the sea-land axis of the home beach, whilst the second pair of walls was oriented east-west. The black and white striped pattern of opposite walls could be moved in pairs and in the same direction (speed=4.8 cm s(-1)). The results demonstrate that the optic flow sandhoppers experience when moving on the sea-land axis of their home beach influences their direction of travel and could help sandhoppers in maintaining a straight path to reach favourable ground by the shortest route.

가상착의 시스템을 이용한 팬츠 스타일과 기하학 무늬의 특성에 따른 시각적 효과

This study evaluates the difference of visual effect according to pant style and geometric pattern. The researcher made 28 stimuli-combination of four pant Stiles (classic, baggy, skinny, and bell-bottom) and seven geometric pattern (large vertical stripe, small vertical stripe, large horizontal stripe, small horizontal stripe, large check, small check, and hound's tooth check). The test involved 96 female college students. The stimuli were made with the i-Designer computer program. The panels tested the computer screen images of all manikins wearing pants. A 7-point scale was used to evaluate each image. For the data analysis, ANOVA and Duncan-test were applied along with an SPSS program. The results of this study are as follows. Three factors (lower-body compensation, abdomen highlight, and length compensation) influenced the visual effect pant styles and geometric patterns. The skinny style and large vertical stripe evaluated positively in elongated height and leg length and a slimmer overall body. It was shown that the vertical stripe pattern was evaluated as more positive than the horizontal stripe pattern in the visual effect; particularly, the results showed distinct aspects in the classic pants style. The mutual influence of the visual effect (according to pants style and geometric pattern) were indicated as two factors of lower-body compensation and length compensation. A more positive visual effects resulted in a higher mutual influence on pant style and geometric pattern.

Automated measurement of spectral sensitivity of motion vision during optokinetic behavior

Optokinetic behavior is a commonly used paradigm to conveniently determine sensitivities of motion vision in animals. The optokinetic reflex (OKR) compensates global image motion on the retina by head and eye movements. It can reliably be elicited without training the test animal. In most OKR behavior experiments the animal is stimulated either with a rotating drum containing a pattern of vertical stripes or with computer monitors displaying a moving stripe pattern. In many of these studies, sensitivity thresholds are measured based on the subjective judgment of the experimenter. In this paper, we describe an alternative method to induce and measure OKR behavior. Our setup consists of a metal drum into which a slide is projected via a 360° panoramic mirror, using a spectrally filtered LED as light source. The slide is mounted on a motor-driven turntable whose rotation leads to a horizontal movement of the stimulus on the drum’s wall, accordingly. By this means a spatial, temporal, and spectral well-defined and flexible panoramic stimulation is achieved. The animal’s head movements are video recorded under infrared illumination and tracked online. We introduce an objective criterion to automatically determine sensitivity thresholds based on the correlation of the animal’s head angle with the stimulus position. We exemplarily used this setup for an experiment that could not be performed with the state-of-the-art setup consisting of four monitors—the measurement of spectral sensitivity thresholds of the OKR behavior in turtles.

Pattern classification of ShearWaveTM Elastography images for differential diagnosis between benign and malignant solid breast masses

ShearWave™ Elastography (SWE) provides a quantitative measurement of tissue stiffness and may improve characterization of breast masses. However, the significance of Young's modulus measurements and appropriate SWE evaluation criteria has not been established yet. To assess the usefulness of the pattern classification and Young's modulus measurements in the differential diagnosis between benign and malignant solid breast masses. Ninety-six patients (age range 18-84 years, mean 54 years) with 100 solid breast masses who underwent tissue sampling after a US examination were analyzed. We tried to create a visual pattern classification based on the SWE images. After classifying the visual patterns, the Young's modulus of the lesions was measured in every case. It was possible to classify the images into four patterns by the visual evaluation: no findings (coded blue homogeneously; Pattern 1), vertical stripe pattern artifacts (Pattern 2), a localized colored area at the margin of the lesion (Pattern 3), and heterogeneously colored areas in the interior of the lesion (Pattern 4). There were 17 Pattern 1 lesions, 14 Pattern 2 lesions, 20 Pattern 3 lesions, and 49 Pattern 4 lesions. When Patterns 1 and 2 were assumed to be benign, and Patterns 3 and 4 were assumed to be malignant, the sensitivity and specificity were 91.3% (63/69) and 80.6% (25/31), respectively. The mean Young's modulus measurements of the benign and the malignant lesions were 42 kPa and 146 kPa, respectively (P < 0.0001). No significant differences were found between benign and malignant lesions in Pattern 3. In Pattern 4, however, the Young's modulus of the benign lesions (50 kPa) was lower than the smallest Young's modulus of malignant lesions (61 kPa). The visual pattern classification and adding Young's modulus measurements may improve characterization of solid breast masses.

Invertebrate Memory: Honeybees with a Sense ofDéjà Vu

Recent studies of visual sequence learning in honeybees have investigated the bees' ability to perform delayed-matching-to-sample and their short-term memory during such tasks. The insect's successful performance raises questions about the underlying mechanisms.

Visual discrimination learning in the water maze: a novel test for visual acuity

Learning about space, the environment and specific objects comprising three-dimensional arrangements requires processing of visual information. As learning and memory experiments in mammals rely heavily on normal processing of visual cues, drug-induced disruption of acquisition learning or memory formation necessitates the important control for visual acuity. A popular task used frequently for rats is the Morris water maze. However, previously used visual tasks in the water maze only control for gross visual disturbances. Here we describe a new training procedure enabling visual acuity to be tested in the water maze. Animals were trained to discriminate between two cue cards containing a pattern of vertical black and white stripes. Cards were presented in two adjacent quadrants separated by a barrier with the escape platform located in front of the smaller stripes (1 cm wide). Once 80% correct responses were attained, the wider cue card (normally 5 cm wide stripes) was randomly changed to gratings of 1, 2, 3, 4, 5, and 10 cm width. Animals learned the discrimination with acuity of 1.5 c/deg. A detailed analysis of the swim patterns further suggests that, independent of the grating used, animals make a choice immediately after release and swim along the walls towards the cue. In a further acuity test taken a few weeks later when animals were given saline infusions, performance was better than in the first test suggesting an effect of learning. This novel test may prove useful in determining subtle drug-induced deficits in visual acuity that may contribute to disruption of spatial performance in the water maze.

Sigma-optokinetic nystagmus in squirrel monkeys elicited by stationary stripe patterns illuminated by regular and random-interval flash sequences.

Eye position and angular velocity were measured in squirrel monkeys (Saimiri sciureus) by means of the electromagnetic scleral search-coil technique. Horizontal sigma-optokinetic nystagmus (sigma-OKN) was elicited by a stationary, stroboscopically illuminated, periodic, vertical-stripe pattern lining a vertical cylinder. The relationship between the mean slow-phase eye angular velocity, Ve, of sigma-OKN and the product of pattern period, Ps, and flash frequency, f(s), was determined. When Ve approximated k x Ps x f(s) (deg x s(-1)) and k was an integer > or = 1, the sigma-paradigm was fulfilled. Sigma-OKN could be evoked in different "modes", whereby k approximated 1, 2,...n. The sigma-OKN properties of squirrel monkeys were similar to those measured for sigma-OKN in the "stare" mode in man, with the exception of a long-lasting optokinetic afternystagmus (sigma-OKAN) appearing in the monkey. A considerable amount of temporal variability in flash sequence intervals ("temporal noise"), causing retinal error signals that interfered with the sigma-paradigm, was accepted by the visuo-motor system without interruption of sigma-OKN. This observation was explained by the operation of a short memory device for perception of visual motion. The internal gain, g(i), which relates the retinal "error" displacement velocity, Vr, and Ve depended, in turn, on Vr according to a function resembling the known relationship between neuronal activity of NOT (nucleus of the optic tract) nerve cells and Vr. This observation may be taken as direct proof that sigma-OKN can be explained by a centrally preprogrammed relationship between the retinal velocity, Vr, and the OKN slow-phase eye velocity, Ve. It is stipulated that the sum of Vr and efference copy signals generated in cortical or subcortical gaze centers is the essential component controlling the perceived velocity of the sigma-movement, whereby a short-term integrator plays a role for squirrel monkey sigma-OKN. When the flash frequency, f(s), was modulated periodically according to a sinewave or "triangular" function at a rate below 0.5 cycles x s(-1), Ve was found to respond with a corresponding modulation, provided the modulation amplitude did not exceed 50% of the mean flash rate. When the latter occurred, nonlinear responses could be observed. A similar response was found when the speed of "real" optokinetic stimuli was varied sinusoidally. Under these experimental conditions, however, the amplitude of the Ve variation yielded up to 1.0 approximately linear responses.

Mesoscale Charge-Ordering in Transition Metal Oxides: Formation and Signatures

The authors briefly outline the value of an inhomogeneous (unrestricted) Hartree-Fock plus Random Phase approach for understanding the types and properties of mesoscopic patterns of localized small polarons in transition metal oxides. Using a multiband Peierls-Hubbard model for a hole-doped CuO{sub 2} layer as an illustrative example, they demonstrate the appearance of correlated high-energy (electronic) and low-energy (localized phonon and spin-wave) signatures of various vertical, diagonal, metal-centered, and oxygen-centered mesoscopic stripe patterns of localized holes (small polarons).

Contrast sensitivity for the stationary and drifting vertical stripe patterns in patients with optic nerve disorders.

Subjective contrast sensitivity for the stationary and horizontally drifting vertical stripe patterns was measured in normal subjects and in patients with glaucoma, optic neuritis and optic atrophy. Contrast sensitivity was also determined objectively using an eye movement reflex (optokinetic nystagmus) recorded by means of electro-oculography. The contrast sensitivity for the drifting stripe patterns in normal subjects was characterized by a depression of sensitivity at the high spatial frequency and an increased contrast sensitivity at the low spatial frequency in comparison with the results of stationary stripe patterns. The measurement of contrast sensitivity for the horizontally drifting vertical stripe patterns was found to be more sensitive for detection of minor damage to the optic nerve than that for the stationary patterns. The results of the subjective contrast sensitivity and the objective one determined using an eye movement reflex showed a good correlation.

Visual detectability gradients: Effect of high-speed visual experience

The detectability of a target pattern presented briefly with a number of similar nontarget patterns varies as a function of the spatial location of the target. Previous work attributes these detectability gradients to a visual search process—a non-eye movement serial scan—that examines a decaying neural representation of the image. ( Heron, 1957 Efron, Yund, & Nichols, 1987 Efron, Yund, & Nichols, 1990a Efron, Yund, & Nichols, 1990b Efron, Yund, & Nichols, 1990c Efron, Yund, & Nichols, 1990a Efron, Yund, & Nichols, 1990b Efron, Yund, & Nichols, 1990c. The results reported in the companion paper ( Ostrosky-Solis, Efron, & Yund, 1991) indicated that literacy did not affect overall performance levels but did influence scanning behavior: “… reading, or learning to read, caused the scanning mechanisms of literate subjects to adopt more consistent scan paths, from subject to subject, than they would have adopted without this reading experience.” The purpose of the present experiment was to determine the effect on this scanning mechanism, if any, of an entirely different type of visual experience —the high-speed visual processing required of tennis players. Unlike reading which requires the linguistic interpretation of a highly structured visual input, tennis skill requires rapid target detection and tracking in three-dimensional visual space as well as large scale visual-motor coordination. As in the previous experiments, subjects were required to detect a vertical stripe pattern among a number of similar non-target patterns. The experiment was performed on a group of 52 tennis players and on an age- and sex-matched group of 52 non-tennis players. The overall accuracy of target detection was greater among the tennis players than among the non-tennis players and, of more interest, there was a significant difference in the detectability gradients. The detection advantage of the tennis group seemed to reach its maximum in the first half of the scan and then to deteriorate as the scan proceeded. These results indicate that visual experience other than reading can affect the habitual activity of the scanning mechanism.

Contrast transfer function of the visual system

Visually evoked potentials were used to determine the spatial contrast response function of the visual system and the visual acuity of the pigeon. The spatial contrast response describes the relationship between the contrast in a pattern of vertical stripes, whose luminance is a function of position, and the amplitude of the visually evoked response at various spatial frequencies for a given temporal frequency (pattern reversal frequency); it indicates how particular spatial frequencies are attenuated in the visual system. The visually evoked responses were recorded using monopolar stainless steel electrodes inserted into the stratum griseum superficiale of the optic tectum; the depth of penetration was determined on the basis of a stereotactic atlas. The stimulus patterns were generated on a video monitor placed 75 cm in front of the animal's eye perpendicular to the optic axis. The spatial contrast response function measured at 10% contrast and 0.5 Hz reversal frequency shows a peak at a spatial frequency of 0.5 c/deg, corresponding to 1 degree of visual angle, and decreases progressively at higher spatial frequencies. The high-frequency limit (cut-off frequency) for resolution of sinusoidal gratings, estimated from the contrast response function, is 15.5 c/deg, corresponding to a visual acuity of 1.9 min of arc.