• Title/Summary/Keyword: Low Light

Search Result 4,264, Processing Time 0.034 seconds

Effects of Temperature and Light Intensity on the Growth of Red Pepper(Capsicum annuum L.) in Plastic House During Winter. IV. Growth Responses Influenced by Temperatures and Light Intensities in Growth Chamber (동계 plastic house내 고추(Capsicum annuum L.) 육묘시 온도와 광도가 생장에 미치는 영향 IV. 생장상내 온도 및 광환경 변화에 따른 생장반응)

  • 정순주;이범선;권용웅
    • Journal of Bio-Environment Control
    • /
    • v.4 no.2
    • /
    • pp.125-130
    • /
    • 1995
  • Observations on the seedling growth of red pepper responding to different temperature(10, 20, 3$0^{\circ}C$) and light intensity(5, 15, 25 klux) were made in the growth Chamber during 7 weeks. The results obtained were as follows; 1. Best results of the combinations of temperature and light intensity were obtained from the combinated treatment of 3$0^{\circ}C$ and 25klux. At all of the temperature levels in this experiment, the more the light intensity is high, the more the growth is favor, but at low temperature below 2$0^{\circ}C$ and low light intensity below 15 klux, the growth of red pepper seedlings was decreased markedly. 2. Multiple regression polynomial equations of the characteristics of red pepper seedlings grown in the different combinations of temperature and light intensity fitted well in the plant height, number of leaves, leaf area, stem dry weight and shoot dry weight. 3. Multiple regression polynomial equation to the shoot dry weight was partial differentiated and diagrammatized the response surface using its theoretical value. Light intensity affected more to the shoot dry weight in the temperature below 2$0^{\circ}C$ but above 2$0^{\circ}C$ the role of the temperature showed greatly influence however, interaction effects of light intensity and temperature showed strongly.

  • PDF

Growth and Seedling Quality of Grafted Cucumber Seedlings by Different Cultivars and Supplemental Light Sources of Low Radiation Period and Early Yield of Cucumber after Transplanting (보광 광원 종류에 따른 약광기 품종별 오이 접목묘의 생육과 묘소질 및 정식 후 초기 과실 수량)

  • Hyeong Eun Choi;So Yeong Hwang;Ji Hye Yun;Jin Yu;Jeong Hun Hwang;Eun Won Park;Jeong Kil Koo;Hee Sung Hwang;Seung Jae Hwang
    • Journal of Bio-Environment Control
    • /
    • v.32 no.4
    • /
    • pp.319-327
    • /
    • 2023
  • To harvest marketable cucumbers, high quality seedlings must be used. Producing seedlings in the greenhouse during the low radiation period decreases marketability due to insufficient light for growth. Supplemental lighting with artificial light of different quality can be used to improve low light conditions and produce high quality seedlings. Therefore, this study was conducted to select the appropriate supplemental light sources on the growth and seedling quality of grafted cucumber seedlings during the low radiation period. Three cultivars of cucumber were used as scions for grafting; 'NakWonSeongcheongjang', 'Sinsedae', and 'Goodmorning baekdadagi'. Figleaf gourd (Cucurbita ficifolia) 'Heukjong' was used as the rootstock. The seeds were sown on January 26, 2023, and grafted on February 9, 2023. After graft-taking, cucumbers in plug trays were treated with RB light-emitting diodes (LED, red and blue LED, red:blue = 8:2), W LED (white LED, R:G:B = 5:3:2), and HPS (high-pressure sodium lamp), respectively. Non-treatment was used as the control. Supplemental lighting was applied 2 hours before sunrise and 2 hours after sunset for 19 days. The stem diameter and fresh and dry weights of roots did not differ significantly by supplemental light sources. The plant height and hypocotyl length were decreased in W LED. However, the leaf length, leaf width, leaf area, and fresh and dry weights of shoots were the highest in the RB LED. Seedling qualities such as crop growth rate, net assimilation rate, and compactness were also increased in RB LED and W LED. After transplanting, most of the growth was not significant, but early yield of cucumber was higher in LED than non-treatment. In conclusion, using RB LED, W LED for supplemental light source during low radiation period in grafted cucumber seedlings improved growth, seedling quality, and early yield of cucumber.

Retinal Projection Display for Low Vision Aid

  • Nakamura, Hajime;Ando, Takahisa;Shimizu, Eiji
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2002.08a
    • /
    • pp.1009-1011
    • /
    • 2002
  • We developed a Retinal Projection Display for a low vision aid. This device can be applied to a low vision whose visual sense is weak. In the device, a digital image was formed with spatial light modulator(SLM) and projected onto a retina with the Maxwellian View. The image on this display can be seen clearly without our ocular accommodation and a low vision can see it without correction of a refraction error.

  • PDF

Vertical Type Organic Transistors and Flexible Display Applications

  • Kudo, Kazuhiro
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08a
    • /
    • pp.168-169
    • /
    • 2007
  • Organic transistors are promising in the future development of active devices for flexible, low-cost and large-area photoelectric devices. However, conventional organic field-effect transistors have lowspeed, low-power, and relatively high operational voltage. Vertical type transistors show high-speed and high-current characteristics and are suitable for driver elements of flexible displays.

  • PDF

A Cost-effective Light Emitting Diode-acoustic System for Preclinical Ocular Applications

  • Choi, Hojong;Ryu, Jaemyung;Yeom, Jung-Yeol
    • Current Optics and Photonics
    • /
    • v.2 no.1
    • /
    • pp.59-68
    • /
    • 2018
  • Opto-acoustic systems provide structural and functional information regarding biological tissues. Conventional opto-acoustic systems typically employ continuous or pulsed lasers as transmission sources. Compared to lasers, light emitting diodes (LEDs) are cost-effective and relatively portable excitation sources but are non, coherent. Therefore, in this study, a relatively low cost lens - a type of Ramsden eyepiece - was specially designed to theoretically calculate the illumination and achieve a constant brightness across the pupil of an eye. In order to verify the capability of the developed light-emitting diode-acoustic (LEDA) systems, we carried out experiments on bovine and bigeye tuna eyeball samples, which are of similar size to the human eye, using low frequency (10 MHz) and high frequency (25 MHz) ultrasound transducers. High frequency ultrasound transducers are able to provide higher spatial resolution compared to low frequency ultrasound transducers at the expense of penetration depth. Using the 10 MHz and 25 MHz ultrasound transducers, acceptable echo signals (3.82, 3.94, and 5.84 mV at 10 MHz and 282, 1557, 2356 mV at 25 MHz) from depth greater than 3 cm and 6 cm from the anterior surface of the eye were obtained. We thereby confirmed that the LEDA system using a pulsed LED with the designed Ramsden eyepiece lens, used in conjunction with low and high frequency ultrasound transducers, has the potential to be a cost-effective alternative method, while providing adequate acoustic signals from bovine and bigeye tuna ocular areas.

Cloudification of On-Chip Flash Memory for Reconfigurable IoTs using Connected-Instruction Execution (연결기반 명령어 실행을 이용한 재구성 가능한 IoT를 위한 온칩 플래쉬 메모리의 클라우드화)

  • Lee, Dongkyu;Cho, Jeonghun;Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.14 no.2
    • /
    • pp.103-111
    • /
    • 2019
  • The IoT-driven large-scaled systems consist of connected things with on-chip executable embedded software. These light-weighted embedded things have limited hardware space, especially small size of on-chip flash memory. In addition, on-chip embedded software in flash memory is not easy to update in runtime to equip with latest services in IoT-driven applications. It is becoming important to develop light-weighted IoT devices with various software in the limited on-chip flash memory. The remote instruction execution in cloud via IoT connectivity enables to provide high performance software execution with unlimited software instruction in cloud and low-power streaming of instruction execution in IoT edge devices. In this paper, we propose a Cloud-IoT asymmetric structure for providing high performance instruction execution in cloud, still low power code executable thing in light-weighted IoT edge environment using remote instruction execution. We propose a simulated approach to determine efficient partitioning of software runtime in cloud and IoT edge. We evaluated the instruction cloudification using remote instruction by determining the execution time by the proposed structure. The cloud-connected instruction set simulator is newly introduced to emulate the behavior of the processor. Experimental results of the cloud-IoT connected software execution using remote instruction showed the feasibility of cloudification of on-chip code flash memory. The simulation environment for cloud-connected code execution successfully emulates architectural operations of on-chip flash memory in cloud so that the various software services in IoT can be accelerated and performed in low-power by cloudification of remote instruction execution. The execution time of the program is reduced by 50% and the memory space is reduced by 24% when the cloud-connected code execution is used.

Low Rate VLC Receiver Design Using NCP302 Voltage Detector for IoT/IoL Connected Smart Homes

  • Lee, Beomhee;Mariappan, Vinayagam;Khudaybergenov, Timur;Han, Jungdo;Cha, Jaesang
    • International journal of advanced smart convergence
    • /
    • v.7 no.4
    • /
    • pp.50-56
    • /
    • 2018
  • The Internet of Things (IoT) and Visible Light Communication (VLC) is opening up new services in lighting industry by integrating sensory network features in addition to standard illumination functionality. In this progressive developments, the next generation lighting devices for smart homes are capable to sense the environmental conditions and transfer the captured data through lights to gateway controller to access remotely. The smart home environmental sensor information's are few kbps only so VLC systems need to built-in with low rate light connectivity to transfer data to the gateway. To provide error free communication, the quality of a received light signal is important to be considered when designing an VLC receiver. Therefore, this paper proposes the design of robust low rate IoL receiver design using NCP302 voltage detector for micro controller to adapt the IoT/IoL front end module for system integration. To evaluate the proposed system performance, the Arduino UNO based IoT/IoL controller designed with lighting, sensors and lights connectivity interfaces. The experimental result shows that the robust interference rejection is feasible on proposed VOL receiver and possible to have an error-free communication up to 10 kbps at a low SNR using OOK modulation.

Real-Time Hardware Design of Image Quality Enhancement Algorithm using Multiple Exposure Images (다중 노출 영상을 이용한 영상의 화질 개선 알고리즘의 실시간 하드웨어 설계)

  • Lee, Seungmin;Kang, Bongsoon
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.22 no.11
    • /
    • pp.1462-1467
    • /
    • 2018
  • A number of algorithms for improving the image quality of low light images have been studied using a single image or multiple exposure images. The low light image is low in contrast and has a large amount of noise, which limits the identification of information of the subject. This paper proposes the hardware design of algorithms that improve the quality of low light image using 2 multiple exposure images taken with a dual camera. The proposed hardware structure is designed in real time processing in a way that does not use frame memory and line memory using transfer function. The proposed hardware design has been designed using Verilog and validated in Modelsim. Finally, when the proposed algorithm is implemented on FPGA using xc7z045-2ffg900 as the target board, the maximum operating frequency is 167.617MHz. When the image size is 1920x1080, the total clock cycle time is 2,076,601 and can be processed in real time at 80.7fps.