Tissue physical property in the head of small toothed whales: Effect on the clicks propagation and directivity
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In the current study, the distribution of acoustic impedance in the head of harbor porpoise and striped dolphin were reported and the transmission factor in the head was calculated. Clicks properties are considered to be closely connected to the structure of sound producing organ, however, few effective investigations have been carried out to reveal the cause of the species diversity of clicks properties. Clicks of toothed whales has been confirmed to be produced at the dorsal barsae (DB) and propagated to the melon where the clicks’ beam is progressively focused, and emitted into the seawater from the emitting surface (ES), a circular aperture at the frontal part of the melon. In our observation of the melon, a continuous gradients were observed from DB to ES for three species. At the ES, acoustic impedance of melon was matched with that of seawater. This mechanism would enable efficient click propagation and emission. The estimated directivity of clicks only from the transmission factor was much weaker than observed directivity, which suggests that the directivity of clicks is strongly affected by the refraction in the melon than a reflection and attenuation in the head tissue.Keywords:
Directivity
Melon
Aperture (computer memory)
The crossed-waveguide broad-wall-to-broad-wall directional coupler is a compact device capable of good performance over a wide frequency band. However, no complete design procedure is available. The small aperture coupling theory of this broad-wall (Moreno) coupler is reviewed and extended. It is shown that a lower limit on the directivity is given by the ratio of magnetic polarisability to electric polarisability for the coupling apertures. Hence, directivity may be improved by using very narrow crossed slots for coupling. It is also shown that the coupling and lower limit on directivity may be calculated for any slot width by using published values of crossed slot polarisabilities. The results of coupling measurements on Moreno couplers are presented in the paper to demonstrate the accuracy of the small-aperture design procedure. Application of these results should permit the broad-wall cross coupler to be used in a wider range of applications.
Directivity
Aperture (computer memory)
Waveguide
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Melon (Cucumis melo L.) is a plant that has economic value and has been cultivated in several areas of Indonesia with intensive fertilization. The mineral nutrient that is expected to improve the quality of melon growth and fruit is silica. The aim of the research was to improve the growth and melon fruit quality by addition of silica fertilizer. The treatments in this experiment were the application of silica (Novelgro, water soluble) which was carried out on melon plants with silica concentrations of 0.67; 1.33 ppm; and control (without silica). The results showed that silica increased the plant height, leaf area, and diameter of melon fruit. Melon plant with silica treatment of 1.33 ppm had silica content in the high category (>4% Si) which was 5.31% in the skin of the fruit. Moreover, the addition of silica can prolong the fruit storage period in room temperature compared to control.
Melon
Cucumis
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'Piel de Sapo' is one of the most consumed market class of melons in the Mediterranean area and it represents an important economic crop in Spain. The 'Mini PS' melon breeding line, which bears two main introgressions from the dudaim 'Queen's pocket' melon in the Piel de Sapo genetic background, was evaluated for its fruit quality traits in three environments. Some interesting commercial characteristics were detected, such as a notable decrease in the fruit weight and a rounder shape, compared with Piel de Sapo, while the other quality traits were not altered. Thus, this mini melon line, ideal as a personal melon, may be useful in the development of new melon cultivars.
Melon
Queen (butterfly)
Line (geometry)
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บทคดยอ การวจยเรองการเพาะเลยงแตงโมในหลอดทดลองไดทำการศกษาเปอรเซนตการงอกของเมลดแตงโมทไดจากผลแตงโมทใชบรโภค และเปรยบเทยบการเจรญเตบโตของแตงโมในสารละลายธาตอาหารสตร MS และสตรของ Knop ทำการศกษาการงอกของเมลดแตงโมในหลอดทดลองในอาหาร MS ในสภาวะปลอดเชอเปรยบเทยบกบการงอกของเมลดทเพาะในแผนฟองนำ ทชมดวยนำ ในการศกษาการเจรญเตบโตของแตงโมในสารละลายธาตอาหาร ใชวธการนำ ตนออนแตงโมทงอกจากเมลดทเพาะในแผนฟองนำ มาเพาะเลยงในสารละลายธาตอาหารสตร MS และสตรของ Knop ทำการวดความเจรญ เตบโต ในดาน ความสงของตน ขนาดของใบ จำ นวนใบ และการออกดอก เปนระยะๆผลการศกษาพบวาแตงโมมอตราการงอกของเมลดเฉลย 26.79% โดยใชเวลาในการงอก4 .5วน อตราการงอกของเมลดแตงโมในสภาพแวดลอมปดในหลอดทดลองในอาหารสตร MS มอตราการงอกของเมลดเฉลย 32.99% และใชเวลาในการงอกเฉลย 4 วน สวนอตราการงอกของเมลดแตงโมในภาชนะเปดในแผนฟองนำทชมดวยนำ มอตราการงอกของเมลดเฉลย 20.60% และใชเวลาในการงอกเฉลย 5 วน อตราการงอกของเมลดและเวลาทใชในการงอกของแตงโมในทงสองสภาวะนมความแตกตางกนอยางมนยสำคญท Level of significant α = 0.05ตนแตงโมสามารถเจรญเตบโตไดในสารละลายธาตอาหารสตร MS และสตรของ Knopแตงโมมลำตนทยาวขน มใบและออกดอกในชวงเวลา 35 วน แตงโมทเจรญเตบโตในสารละลายธาตอาหารสตรของ Knop มการเจรญเตบโตไดดกวา มลำตนทยาวกวา มใบทใหญกวา และมจำนวนดอกมากกวา แตงโมทเจรญเตบโตในสารละลายธาตอาหารสตร MS Abstract The research on in vitro water melon culture was performed for studying the percentageof water melon’s seed germination and for comparing growth and development of water melon inhydroponics culture using MS and Knop’s recipies. Water melon’s seed germination wascompared between in vitro sterile condition using MS media and the open condition using spongesoaked with water as supporting material. MS medium was used for in vitro culturing water melon.The growth and development of water melon was determined. MS and Knop’s recipies were usedin hydroponics culture. The growth and development of hydroponics water melon were comparedin the aspect of shoot length, leaf size, number of leaves and flowering between that in the MS andthat in the Knop’s recipies.The result showed that the mean germination rate of water melon was 26.79%. Thegermination time was 4.5 days. The mean germination rate of water melon in vitro culture was32.99% with in 4 days and the mean germination rate of water melon in open condition usingsponge soaked with water as supporting material was 20.60% with in 5 days. The water melon seedgermination rate and the germination time in both conditions were significantly different at thelevel of significant α = 0.05.Water melons in hydroponics culture were able to grow in both MS and Knop’s recipies.Their stems were longer, leaves were developed and flowers were developed with in 35 days.Hydroponics water melon in Knop’s recipies had higher growth (longer stems, larger leaves, morenumber of flowers) than that in MS recipies.
Melon
Hydroponics
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In this paper are presented the experimental results of changes in directivity patterns of artificial head with three different types of head covers. The mathematical model of human head approximated by radially vibrating spherical cap set in a sphere is discussed. For the purpose of this research, the physical model of a human speaker head is constructed, and the far-field detailed directivity patterns of the model with and without head covers is measured. Hair as porous absorber, cap and straw hat, as sound barriers, are discussed, and their influence on sound wave propagation is considered. Measured detailed directivity pattern changes affected by head covers in far field are calculated in step of ten degrees for spherical coordinates (polar angle and azimuth) and presented in form of two- and three-dimensional polar plots.
Directivity
Human head
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The cutter-head aperture ratio,one of critical parameters for shield tunneling machine stability,secures a critical position in cutter-head design.Based on the interaction between aperture ratio and excavation face,the impact of aperture ratio on dumping rate is first analyzed.Meanwhile,the calculation method for maximum and minimum dumping rates is deduced.In case of cutter-heads with different diameters tunneling in the sand gravel,the dumping rate is then investigated with variation of aperture ratio.Finally,it is detected from analysis results that,when 3 m cutter-head is tunneled in the sand gravel,the aperture ratio ranging from 70% to 85% is appropriate to the excavation face stability.
Aperture (computer memory)
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Tetraploid melon was induced through somaclonal variation from immature cotyledon culture of Qitian No.1. The most effective concentration of BA was 3.0 mg/L to obtain tetraploid variation with chromosome doubling rate of 14.3%. The morphology of diploid and tetraploid melon was comparatively observed, and some quality traits were measured. The results showed that the tetraploid melons are generally larger in morphology than diploid melon. Vitamin C and soluble sugar content in tetraploid melons were significantly higher than those in diploid melons.
Melon
Cucumis
Cotyledon
Chromosome number
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The directivity of a uniformly excited circular aperture in an infinite ground plane is reexamined in the light of recently acquired knowledge related to Q-type integrals. It is seen that depending on aperture size, numerical corrections to the directivity estimates for such apertures can be easily accommodated.
Directivity
Aperture (computer memory)
Ground plane
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Soil nutrients systematic evaluation method was adopted to study soil nutrients and effect of potassium on economic character of seed of melon and seed-melon,yield and benefit of seed-melon.Result showed that potassium could improve economic character of seed of melon and seed-melon,which includes single melon weight,melon seeds weight per melon,melon seeds output ratio,one hundred seed weight of melon seeds,kernels output ratio,and lengthwise and sidewise diameter of melon seeds;and that potassium could increase yield of seed-melon,yield of melon seeds with potash was increased by 157～230 kg/hm~2,increase range was from 9.2% to 13.5%,compared to that without potash;and potassium also increases product value and net income of seed-melon,product value and net income of seed-melon with potash respectively increased by 942～1375(yuan/hm~2) and 818～1104 yuan/hm~2,compared to that without potash.Marginal benefit analysis showed that potash dosage that reaches the highest yield and the maximum profit was 135 kg/hm~2.
Melon
Potash
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The directivity of the ellipsoid head and the dummy head are measured,and the directivity and the interaural level difference of these two artificial head are compared.At last,the applicable condition under which the simple ellipsoid head can be used to replace the dummy head is analyzed.
Directivity
Ellipsoid
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