Splash formation by spherical drops

2001 ◽  
Vol 427 ◽  
pp. 73-105 ◽  
Author(s):  
LIOW JONG LENG
Keyword(s):  
High Resolution ◽  
Quantitative Data ◽  
Water Surface ◽  
High Speed ◽  
Scaling Laws ◽  
Capillary Wave ◽  
Water Drop ◽  
Qualitative And Quantitative ◽  
High Resolution Images ◽  
The Impact

The impact of a spherical water drop onto a water surface has been studied experimentally with the aid of a 35 mm drum camera giving high-resolution images that provided qualitative and quantitative data on the phenomena. Scaling laws for the time to reach maximum cavity sizes have been derived and provide a good fit to the experimental results. Transitions between the regimes for coalescence-only, the formation of a high-speed jet and bubble entrapment have been delineated. The high-speed jet was found to occur without bubble entrapment. This was caused by the rapid retraction of the trough formed by a capillary wave converging to the centre of the cavity base. The converging capillary wave has a profile similar to a Crapper wave. A plot showing the different regimes of cavity and impact drop behaviour in the Weber–Froude number-plane has been constructed for Fr and We less than 1000.

Electrical Probing and Surface Imaging of Deep Sub-Micron Integrated Circuits

1999 ◽  
Author(s):  
Kenneth Krieg ◽  
Richard Qi ◽  
Douglas Thomson ◽  
Greg Bridges
Keyword(s):  
High Resolution ◽  
Integrated Circuits ◽  
Real Time ◽  
High Speed ◽  
Time Signal ◽  
Surface Imaging ◽  
Atomic Force ◽  
Submicron Structures ◽  
High Resolution Images ◽  
Capacitive Loading

Abstract A contact probing system for surface imaging and real-time signal measurement of deep sub-micron integrated circuits is discussed. The probe fits on a standard probe-station and utilizes a conductive atomic force microscope tip to rapidly measure the surface topography and acquire real-time highfrequency signals from features as small as 0.18 micron. The micromachined probe structure minimizes parasitic coupling and the probe achieves a bandwidth greater than 3 GHz, with a capacitive loading of less than 120 fF. High-resolution images of submicron structures and waveforms acquired from high-speed devices are presented.

scholarly journals Experimental Study of Drop Impact on Deep-Water Surface in the Presence of Wind

2018 ◽  
Vol 48 (2) ◽  
pp. 329-341 ◽  
Author(s):  
Xinan Liu
Keyword(s):  
Deep Water ◽  
Water Surface ◽  
Water Drop ◽  
Threshold Value ◽  
Impact Angle ◽  
Drop Impact ◽  
Wind Speeds ◽  
Secondary Droplets ◽  
Low Wind Speeds ◽  
The Impact

AbstractThe effects of wind on the impact of a single water drop on a deep-water surface are studied experimentally in a wind tunnel. Experiments are performed by varying impacting drop diameters, ranging from 2.5 to 4.1 mm and wind speeds up to 6.7 m s−1. The sequence of splashing events that occurred during drop impacts is recorded with a backlit, cinematic shadowgraph technique. The experimental results show that for low wind speeds, an asymmetrical crown forms on the leeward of the periphery of the colliding region after the drop hits the water surface, while a wave swell forms on the windward. Secondary droplets are generated from the crown rim. For high wind speeds with large drop diameters, ligaments are generated from the crown rim on the leeward of the drop impact site. The ligaments grow, coalesce, and fragment into secondary droplets. It is found that both the drag force and surface tension play important roles in the evolution process of the ligaments. The nondimensional K number (K = WeOh−0.4, where We is the Webber number and Oh is the Ohnesorge number) is used to describe the splashing-deposition limit of drop impact. The threshold value of this K number changes with the wind velocity and/or drop impact angle.

Photogrammetric Investigation of the Flying Shape of Spinnakers in a Twisted Flow Wind Tunnel

2009 ◽  
Author(s):  
Kai Graf ◽  
Olaf Müller
Keyword(s):  
Image Processing ◽  
Pattern Recognition ◽  
High Resolution ◽  
Wind Tunnel ◽  
Wind Velocity ◽  
Digital Cameras ◽  
Pattern Recognition Methods ◽  
Twisted Flow ◽  
High Resolution Images ◽  
The Impact

This paper describes a method for the acquisition of the flying shape of spinnakers in a twisted flow wind tunnel. The method is based on photogrammetry. A set of digital cameras is used to obtain high resolution images of the spinnaker from different viewing angles. The images are post-processed using image-processing tools, pattern recognition methods and finally the photogrammetry algorithm. Results are shown comparing design versus flying shape of the spinnaker and the impact of wind velocity and wind twist on the flying shape. Finally some common rules for optimum spinnaker trimming are investigated and examined.

scholarly journals Design for a Highly Stable Laser Source Based on the Error Model of High-Speed High-Resolution Heterodyne Interferometers

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1083
Author(s):  
Hongxing Yang ◽  
Ziqi Yin ◽  
Ruitao Yang ◽  
Pengcheng Hu ◽  
Jing Li ◽  
...  
Keyword(s):  
Measurement Error ◽  
High Resolution ◽  
High Speed ◽  
Beat Frequency ◽  
Error Model ◽  
Laser Source ◽  
Measurement Error Model ◽  
High Resolution Measurement ◽  
Resolution Measurement ◽  
The Impact

Heterodyne interferometers with two opposite Doppler shift interference signals have been proposed for high-resolution measurement with high measurement speed, which can be used in the background of high-speed high-resolution measurement. However, a measurement error model for high-speed high-resolution heterodyne interferometers (HSHR-HIs) has not yet been proposed. We established a HSHR-HI measurement error model, analyzed the influence of beat frequency stability with a simplified optical structure, and then designed an offset-locked dual-frequency laser source with a digital control system to reduce the impact of beat frequency drift. Experiments were used to verify the correction of the measurement error model and the validity of the laser source. The results show that the new laser source has a maximum beat frequency range of 45 MHz, which shows the improvements in the measuring speed and resolution.

scholarly journals Dampak Pengembangan Pariwisata Terhadap Perekonomian Masyarakat Sekitar Objek Wisata di Dieng Kabupaten Wonosobo

2018 ◽  
Vol 6 (3) ◽  
pp. 320-327
Author(s):  
Sani Alim Irhamna
Keyword(s):  
Quantitative Data ◽  
Secondary Data ◽  
Likert Scale ◽  
Economic Conditions ◽  
Qualitative And Quantitative ◽  
Descriptive Research ◽  
The Impact ◽  
The Village ◽  
Visitor Attractions ◽  
Tourism Revenue

Penelitian ini mengidentifikasi dampak yang ditimbulkan dari adanya pengembangan objek wisata terhadap kondisi perekonomian masyarakat sekitar. Penelitian ini dilakukan di Desa Dieng, Kecamatan Kejajar, Kabupaten Wonosobo. Penelitian ini dilakukan karena meningkatknya pengunjung objek wisata dan pendapatan sektor pariwisata yang berpengaruh terhadap perekonomian masyarakat sekitar objek wisata. Jenis penelitian ini menggunakan metode penelitian deskriptif yang dilengkapi data kualitatif dan kuantitatif baik data primer maupun sekunder. Penelitian ini menggunakan alat Skala Likert untuk menentukan hasil penelitian. Tujuan dari penelitian ini untuk mengetahui gambaran kondisi pariwisata, dan mengidentifikasi dampak yang ditimbulkan dari adanya pengembangan pariwisata terhadap kondisi perekonomian masyarakat sekitar. Hasil dari penelitian ini menunjukkan adanya peningkatan fasilitas, pelayanan objek wisata setelah adanya pengembangan, akan tetapi ada penurunan pada bidang kebersihan dan keamanan. Persentase pendapatan masyarakat mengalami peningkatan yang dihitung menggunakan Skala Likert dari 53,3% menjadi 68,5%, tingkat kesempatan kerja rendah dengan persentase hanya sebesar 29,5%. This study identifies the impact of the tourism development of economic conditions surrounding community. This research was conducted in the village of Dieng, District Kejajar, Wonosobo regency. This research was done because of the rise in visitor attractions and tourism revenue that affect the economy of the surrounding community attraction. This research uses descriptive research method qualitative and quantitative data include both primary and secondary data. This study uses a Likert Scale tool to determine the results. The purpose of this study to describe the condition of tourism, and to identify the impact of the development of tourism on the economy of surrounding communities. The results of this study showed an increase in facilities and services, attraction after their development, but there is a decrease in the field of hygiene and security. The percentage of people's income has increased which is calculated using a Likert Scale from 53.3% to 68.5%, the low employment rate with a percentage of only 29.5%.

scholarly journals Teaching with Scratch in Compulsory Secondary Education

2016 ◽  
Vol 11 (02) ◽  
pp. 67 ◽  
Author(s):  
Ana Maria Ortiz-Colon ◽  
Jose Luis Maroto Romo
Keyword(s):  
Secondary Education ◽  
Research Design ◽  
School Performance ◽  
Student Motivation ◽  
Quantitative Data ◽  
Creative Thought ◽  
Qualitative And Quantitative ◽  
Teaching Unit ◽  
Field Notes ◽  
The Impact

The article analyzes the impact that the use of Scratch has in a group of students of Compulsory Secondary Education in the development of the teaching unit. For this we have studied the evolution of creative thought and analyzed the considerations made by the different actors involved, students and teachers. Qualitative and quantitative data are intended to complement the type of evidence and notes in research design followed. The tools used were the interview, field notes, diary of the researcher and the rubric adapted and created by Eduteka. The research results indicate that with the use of Scratch language students get better grades and are more motivated. As a conclusion, we can say that the application of the Scratch program improves school performance and student motivation significantly.

scholarly journals ALTERNATIVE CONTROL OF INSECT PESTS IN VEGETABLE PLANTS USING LOCAL WISDOM APPROACH

2016 ◽  
Vol 4 (1) ◽  
pp. 53
Author(s):  
Lukmanul Hakim ◽  
Abdul Muis
Keyword(s):  
Quantitative Data ◽  
Quantitative Methods ◽  
Qualitative Data ◽  
Insect Pests ◽  
Ricinus Communis ◽  
Alternative Control ◽  
Qualitative And Quantitative ◽  
Qualitative And Quantitative Methods ◽  
Trap Plants ◽  
The Impact

This research aimed to determine the local wisdom of the community of Lembah Seulawah Sub-district, Aceh Besar, Indonesia of controlling insect pests in vegetable plants. In addition, the study intended to examine the impact of using paper as a mechanical trap for insect pests in vegetable plants. Both qualitative and quantitative methods were used in this research. The qualitative data were obtained through interviews with farmers, whereas the quantitative data were collected from an experiment. Thirty randomly-selected respondents were interviewed and then the qualitative and quantitative data processing was performed. The results showed that they still use plant-based materials as insecticides which constitute the local wisdom of controlling insect pests in vegetable plants. The plants used as insecticides were, among others, garlic (Allium satifum), castor bean seeds (Ricinus communis), lemongrass, neem seeds, and thorny amaranth as the trap plants.

scholarly journals Use of Gamification Applications in Science Education

2019 ◽  
Vol 14 (01) ◽  
pp. 4 ◽  
Author(s):  
Cigdem Hursen ◽  
Cizem Bas
Keyword(s):  
Science Education ◽  
Mixed Method ◽  
Quantitative Data ◽  
Science Learning ◽  
Qualitative Data ◽  
Positive Impact ◽  
Learning Motivation ◽  
Primary Students ◽  
Qualitative And Quantitative ◽  
The Impact

In this research, the impact of gamification applications in science education on the science learning motivation of students has been determined and the opinions of students and parents on applications have been discussed. A total of 16 students and their parents partic-ipated in the study. The research was conducted on 4th grade primary students and em-ployed a mixed method consisting of both qualitative and quantitative elements. The moti-vation of students for learning science was obtained through quantitative data, whereas the opinions of students and parents on the usage of gamification applications were gathered through qualitative data. In the study, it was found that applications in science education created a positive impact on the learning motivation of students for science. Additionally, the research results also displayed that students and parents have positive opinions on the usage of gamification in science education.

Gender and Disaster: The Impact of Natural Disasters on Violence Against Women in Nepal

2021 ◽  
pp. 002190962110624
Author(s):  
Tamsin Bradley ◽  
Zara Martin ◽  
Bishnu Raj Upreti ◽  
Bashnu Subedu ◽  
Sumeera Shrestha
Keyword(s):  
Climate Change ◽  
Natural Disasters ◽  
Natural Disaster ◽  
Violence Against Women ◽  
Quantitative Data ◽  
Gendered Violence ◽  
Qualitative And Quantitative ◽  
Adverse Impacts ◽  
The Impact ◽  
Climate Disasters

In April 2015, a 7.8 magnitude earthquake hit the Gorkha district of Nepal. This was followed in May by a second earthquake. Nepal experienced another natural disaster in 2017. Floods affected large swathes of the country from east to west. Using both qualitative and quantitative data, this article examines the impact of these climate disasters on violence against women. In doing so, it adds to a small but growing and fundamentally important body of literature that explores the intersections of gendered violence and natural disaster. It is well-established that 35% of women worldwide have experienced physical and/or sexual violence. What we know much less about is how other events impact on these figures. Given the growing intensity of climate change and the reality that adverse impacts are here to stay, understanding the detrimental legacy of natural disasters is now more urgent than ever.

Surveys as Tools to Measure Qualitative and Quantitative Data

2015 ◽  
pp. 415-434
Author(s):  
Ellen Boeren
Keyword(s):  
Survey Research ◽  
Research Methods ◽  
Quantitative Data ◽  
Quantitative Research ◽  
Face To Face ◽  
Qualitative And Quantitative ◽  
Survey Questions ◽  
Survey Methodologies ◽  
The Impact ◽  
Insight Into

This chapter critically explores the tendency of research methods books to discuss survey research under the header of quantitative research approaches. It starts by providing a brief history on survey research, sets out core definitions, and situates survey research in the current methodological literature. The chapter then explores the nature of specific survey questions and the differences in format based on whether one is gathering qualitative versus quantitative data. Finally, the chapter explores the impact of survey methodologies and provides insight into the format of questions to be used during telephone, face-to-face, and self-completing surveys.

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