Study on Chironomid Larvae Recognition Based on DWT and Improved KNN

A chironomid larvae images recognition method based on wavelet energy feature and improved KNN is developed. Wavelet decomposition and color information entropy are selected to construct vectors for KNN that is used to classify of the images. The distance function is modified according to the weight determined by the correlation degree between feature and class, which effectively improves classification accuracy. The result shows the mean accuracy of classification rate is up to 95.41% for freshwater plankton images, such as chironomid larvae, cyclops and harpacticoida.

中考文言文该怎样命制开放性试题

中考文言文阅读题要有一定的开放性,这是命题者、语文教研专家和一线语文教师的共识,但命制怎样的开放性文言文阅读题才算比较理想呢？一、中考开放性文言文阅读题应允许有个性化的回答和不同观点具体地讲,就是要引导考生将阅读材料中的信息和观点与自己的生活经验和观点结合起来答题,至于答案的被接受程度则不在于所持立场,

文言文阅读应该命制怎样的开放性试题

文言文阅读中要有一定的开放性试题,这是命题者、有关学者、语文教研专家和一线语文教师等所达成的共识之一。但文言文阅读究竟命制怎样的开放性试题,才算是比较理想的开放性试题呢？

Preparation of Cr_2O_3-based pigments with high NIR reflectance via thermal decomposition of CrOOH

In order to reduce greenhouse gas emission and urban heat island mitigation, pure and titanium（Ti）-doped Cr2O3 cool pigments were prepared via the thermal decomposition of CrOOH. The result reveals that the pure Cr2O3 pigment presents both a high near-infrared reflectance and excellent yellowish-green color. Meanwhile, titanium was doped to improve the NIR reflectance and strengthen the color. The color of the designed pigments was brighter, and most importantly, the NIR reflectance increased from 84.04% to 91.25% with increasing Ti content from 0 to 0.006% （mole fraction）. However, excessive doping of Ti4＋ for Cr3＋ in Cr2O3 （x（Ti）≥0.008%） decreased the NIR reflectance. One possible reason is that the conductivity type of the Cr2？xTixO3＋δ changed from p-type conduction to n-type conduction with increasing Ti content, accompanied by the change of the electrical resistivity and the NIR reflectance. The prepared yellowish-green Cr2O3 pigments have a great potential for extensive applications in construction and military.

Sensitivity of the suspected blood indicator:An experimental study

AIM： To investigate whether suspected blood indicator （SBI） in capsule endoscopy （CE） is affected by back- ground color and capsule passage velocity. METHODS： Experimental models of the small intestine constructed from paper in a variety of colors were used to simulate the background colors observed in CE im- ages. The background colors studied included very pale yellow, yellow, very pale magenta, light grayish pink, burnt sienna, and deep and dark brown, and red spots were attached inside them. An endoscopic capsule was manually passed through the models. The rate of detection of the red spots by the SBI was evaluated based on the colors of the models and the capsule pas- sage velocities （0.5 cm/s, 1 cm/s, and 2 cm/s）.RESULTS： The rate of detection of the red spots byground color of the model （P 〈 0.001）. Detection rates were highest for backgrounds of very pale magenta, burnt sienna, and yellow, in that order. They were lowest for backgrounds of dark brown and very pale yellow. The rate of detection of red spots by the SBI tended to decrease at rapid capsule passage velocities （1-2 cm/s） compared to slow velocities （0.5 cm/s） for backgrounds of very pale yellow （P = 0.042）, yellow （P = 0.001）, very pale magenta （P = 0.002）, and burnt sien- na （P = 0.001）. No significant differences in the rate of detection were observed according to velocity for light grayish pink （P = 0.643） or dark brown （P = 0.396）. CONCLUSION： SBI sensitivity was affected by back- ground color and capsule passage velocity in the models. These findings may facilitate the rapid detection of bleeding lesions by CE.

Comparison of growth and survival of larvae among different shell color stocks of bay scallop Argopecten irradians irradians(Lamarck 1819)

In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis.

Correlated Color Temperature Tunable Multi-chip Light Emitting Diodes Light Source Design

One of the methods to derive white light from light emitting diodes(LEDs)is the multi-chip white LED technology,which mixes the light from red,green and blue LEDs.Introduced is an optimal algorithm for the spectrum design of the multi-chip white LEDs in this paper.It optimizes the selection of single color LEDs and drive current controlling,so that the multi-chip white LED achieves the target correlated color temperature(CCT),as well as high luminous efficacy and good color rendering.A CCT tunable LED light source with four high-power LEDs is realized based on the above optimal design.Test results show that it maintains satisfactory color rendering and stable luminous efficacy across the whole CCT tuning range.Finally,discussed are the design improvement and the prospect of the future applications of the CCT tunable LED light source.

Three-Rainbow Coloring of Split Graphs

After a necessary condition is given, 3-rainbow coloring of split graphs with time complexity O(m) is obtained by constructive method. The number of corresponding colors is at most 2 or 3 more than the minimum number of colors needed in a 3-rainbow coloring.

Beyond Pure Frequency and Phases Exploiting： Color Influence in SSVEP Based on BCl

A BCI （brain computer interface） established a new direct communication channel using the brain activity between the human brain and machine. The visual stimulus with a certain frequency is present to the BCI users; it exists in a particular condition to observe a continuous brain response respect to frequent of visual stimuli. A significant problem when engaged the SSVEP （steady-state visual evoked potential） based on BCI, it will be exhausted and may suffer for the users when staring at flashing stimuli. This experimental study investigates how the differences in LED＇s-colors influence of SSVEP with respect to （i.e., frequencies and phases）. The result shows that the visualization of phase delays in lower frequencies greater than in higher frequencies.

EFFECTIVE APPEARANCE MODEL FOR PROBABILISTIC OBJECT TRACKING

This paper presents a robust object tracking approach via a spatially constrained colour model. Local image patches of the object and spatial relation between these patches are informative and stable during object tracking. So, we propose to partition an object into patches and develop a Spatially Constrained Colour Model (SCCM) by combining the colour distributions and spatial configuration of these patches. The likelihood of the candidate object is given by estimating the confidences of the pixels in the candidate object region. The appearance model is learnt from the first frame and the tracking is carried out by particle filter. The experimental results show that the proposed tracking approach can accurately track the object with scale changes, pose variance and partial occlusion.

Studies on the Correlation between Germination and cAMP Content of Different Color Chlamydospores in Ustiloginoidea virens

Ustilaginoidea virens is the causal agent of a serious disease of rice. To reveal the relationship between germination and the 3'-5'-cyclic adenosine monophosphate(c AMP) content from the dormant(black or green-black) and non-dormant(yellow)chlamydospore in Ustiloginoidea virens,this study adopts ultrasonic-bath method and high-performance liquid chromatography(HPLC) method, for extraction c AMP content of the different color chlamydospore. The results demonstrated that, as for the freshly chlamydospores collected from the false smut balls during their germination, c AMP content of yellow chlamydospore appeared a slight growth during 0-12 h, and showed a rapid declining as the germination time extended(12-48 h). Above all, in yellow chlamydospores, the germination rate and the content of c AMP presented a very notably negative correlation(|r|=0.861 9>r0.01=0.834), but the correlation between germination rate and content of c AMP was not obvious in black chlamydospores. The germination rate and the content of c AMP presented a notably positive correlation under different storage period(0, 2, 4, 6, 8,10 months) of the two color chlamydospores(the yellow of chlamydospore: |r | = 0.785 1 > r0.05= 0.707; the black of chlamydospore: |r| = 0.957 9 > r0.05= 0.707).

Surface resistivity of carbonaceous fiber/PTFE antistatic coatings

Abstract： PAN （Polyacrylonitrile）-based carbonaceous fibers were prepared at the heat treatment temperature （HTT） range of 650 to 900 ℃. The relationships among HTT, carbon content and volume resistivity of the carbonaceous fibers were investigated. The carbonaceous fibers/PTFE （Polytetrafluoroethylene） antistatic coatings were prepared by the spraying technology and the effects of carbonaceous fibers and pigments on surface resistivity of the coatings were systematically discussed. Micrographs provide insight into the antistatic mechanism of the coating. The results show that carbon content of the carbonaceous fibers increases from 68.8% to 74.8% （mass fraction） and the volume resistivity decreases drastically from 1.94× 10^-3 to 8.27× 10 ^-2.cm. The surface resistivity of the antistatic coating is adjustable between 10^5 and 10^8Ω2 to fit the different antistatic materials. Static is dissipated by a conductive network of short fibers and the tunneling effect between the neighboring fibers and conductive pigments. Conductive pigments make the conductive network more perfect and improve the antistatic ability, but insulating pigments acting as barriers for the formation of conductive channel increases the surface resistivity of the coatings. The influence of pigments on the surface resistivity drops gradually with the decrease of the carbonaceous fibers volume resistivity.

Glass Substrates for OLED Lighting with High Out-coupling Efficiency

Glass substrates which realize high out-coupling efficiency OLEDs （organic light emitting diodes） were developed. A scattering layer whose matrix was made of high refractive index glass was formed on a glass substrate, and pores in the glass matrix work as scattering centers. The out-coupling efficiency of an OLED using this substrate is 1.8 times higher compared with an OLED using an untreated glass substrate. Furthermore angular dependency of the color and color variation between panels can be successfully suppressed.

九鼎的来历与失传

九鼎的来历与失传莫金山据史载，在夏商周三代的器物中，一组由九个鼎组成的九鼎，最为庄重名贵，也最为神秘。它是王权的象征，得到它就等于取得了国家政权，失掉它就意味着丧失了国家的政权。鼎，作为一种炊器和礼器，早在新石器时代便有了，它成为镇国之宝，其中是有历...

Can sexual selection and disassortative mating contribute to the maintenance of a shell color polymorphism in an inter- tidal marine snail？

Littorina fabalis is an intertidal snail commonly living on the brown algae Fucus vesiculosus and showing frequent shell-color polymorphisms in the wild. The evolutionary mechanism underlying this polymorphism is currently unknown. Shell color variation was studied in mated and non-mated specimens of this species from different microareas in one locality from NW Spain, in order to estimate sexual selection and assortative mating that may （still） be operating in this population. The analyses across microareas allowed us to investigate frequency-dependent selection and assortative mating components, mechanisms that could maintain the polymorphism. The presence of shell scars caused by crab attacks, an environmental variable not related with sexual selection or assortative mating, was used as experimental control. This study provides new evidence of significant disas- sortative mating and some degree of sexual selection against some shell colors, supporting the results found 21 years ago in a similar study, i.e. in the same species and locality. The similarity of these estimates during the studied period suggests that this experimental approach is consistent and valid to be extended to other populations and organisms. In addition, sexual selection and assortative mating estimates did not change across microareas differing in shell color frequencies, suggesting than the polymor- phism can not be maintained by a frequency-dependent （sexual selection-based） mechanism. Our main hypothesis is that negative assortative mating could contribute to the maintenance of the polymorphism, perhaps by males showing distinct female color preferences when searching for mates [Current Zoology 58 （3）： 463-474, 2012].

Site-Specific Nitrogen Management in Dry Direct-Seeded Rice Using Chlorophyll Meter and Leaf Colour Chart

The need to maintain high rice yields and improve fertilizer nitrogen(N)-use efficiency has fueled the use of tools such as leaf colour chart(LCC) and chlorophyll meter(SPAD meter) in managing fertilizer N based on colour of the leaf. Field experiments were conducted during 2011 to 2013 at Ludhiana, India to assess the need for basal N application and to establish critical threshold values of leaf greenness as measured by LCC and SPAD meter for formulating strategies for in-season management of fertilizer N in dry direct-seeded rice(DDSR). Avoiding application of N at sowing did not adversely affect rice grain yield, indicating that basal N application in DDSR was not necessary and might lead to reduced N-use efficiency. Monitoring N uptake rate during the growing season of DDSR suggested that N uptake rate peaked at the two growth stages: maximum tillering(42 to 56 days after sowing(DAS))and panicle initiation stages(70 to 84 DAS). Using the Cate-Nelson procedure, critical LCC and SPAD meter values for fertilizer N application worked out to be 4 and 37, respectively. Real-time fertilizer N management strategy based on applying 30 kg N ha-1whenever SPAD meter or LCC readings fell below the critical values maintained optimum rice yields along with higher N-use efficiency than that observed by following blanket recommendation for fertilizer N in the region. The fixed-time variable-dose strategy consisted of applying prescriptive doses of 20 kg N ha-1at 14 DAS and 30 kg N ha-1at 28 DAS and corrective doses of 30, 40 or 50 kg N ha-1at 49 and 70 DAS depending upon LCC shade to be ≥ 4, 4–3.5, or < 3.5 and SPAD meter readings to be ≥ 40, 40–35, or< 35, respectively. This strategy also resulted in optimal rice yield along with higher N-use efficiency as compared to the blanket recommendation. This study revealed that in DDSR, fertilizer N could be managed more efficiently using the tools of LCC and SPAD meter than the current blanket recommendation.

Stabilizing electroluminescence color of blue perovskite LEDs via amine group doping

Voltage loading-induced change in the electroluminescence(EL)wavelength of mixed halide perovskite light-emitting diodes(PeLEDs),so-called color-shift,has become an inevitable phenomenon,which is seriously unfavorable to their applications in lighting and display.Here,we achieve color-stable blue PeLEDs via a hydrogen-bonded amine-group doping strategy.Selecting guanidine(GA)or formamidinium(FA)as amine-group(-NH_(2))doping source for CsPbBr_(x)Cl_(3-x)quantum dots(QDs),experimental and theoretical results reveal that the strong N-H…X(X=Br/Cl)bonding can be produced between-NH_(2)dopants and Pb-X lattices,thereby increasing the migration barrier of halide anions.Resultantly,color-stable sky-blue devices were realized with emission peaks fixed at 490.5(GA)and 492.5(FA)nm without any obvious shift as the voltage increases,in sharp contrast devices without N-H…X producing a 15 nm red-shift from 487 to 502 nm.Not only that,maximum external quantum efficiency is improved to 3.02%and 4.14%from the initial 1.3%.This finding offers a convenient boulevard to achieve color-stable PeLEDs with high efficiency.

Superficial Color Patches as a Visual Diagnostic Criterion for Agricultural Management

Soil management matters in semiarid lands are key to have acceptable yields and to preserve diversity. After the major agricultural intensification underwent in the semiarid lands of Monegros, NE Spain, custom tailored tools are needed to reconcile agriculture with habitats conservation. The objectives of this study were to quantify the effect of soil properties of two distinctly colored soils, white patches （WP） and dark patches （DP）, dominant in the arid landscape of the central Ebro Basin, Spain on winter cereal grain yield and to prove that superficial soil color could be used as a visual diagnostic criterion for evaluation of agricultural practices in arid lands. Significant differences between WP and DP soils were found in gypsum, carbonate contents, available water holding capacity and infiltration rate. The grain yield ranged from 51 to 5 713 kg ha-1. Significantly lower yields （P 〈 0.01） and precipitation-use efficiency （P 〈 0.05） were attained in the WP soils for the three seasons studied. This difference increased with the average rainfall due to the significantly lower soil water infiltration （P 〈 0.01） and water holding capacity （P 〈 0.05） found in the gypseous soils. Our results show that mapping the soil surface color at farm scale can be a low=cost tool for optimizing agricultural practices and recovering the natural vegetation. This approach can be advantageous in similar arid or semiarid environments around the world.

Testing for selection on color and pattern in a mimetic radiation

In this paper, we analyze variation in spectral reflectance and color pattern among populations to demonstrate dra-matic divergence between four distinct morphs of the mimic poison frog Ranitomeya imitator. We also analyze genetic diver-gence in d-loop mtDNA sequences between populations. We then use coalescent-based simulations to demonstrate that the high levels of observed phenotypic divergence are not consistent with levels of genetic divergence expected under neutral drift among populations, implying an important role for selection in driving divergence between these populations .