• Title/Summary/Keyword: magnifying lens

Search Result 15, Processing Time 0.018 seconds

Evaluation of optical properties for the development of high resolution ophthalmic endoscope (고 분해능 안구내시경 개발을 위한 광학적 특성 평가)

  • Lee Bongsoo;Cho Dong Hyun;Kim Sin;Cho Hyosung
    • Korean Journal of Optics and Photonics
    • /
    • v.15 no.5
    • /
    • pp.429-434
    • /
    • 2004
  • An ophthalmic endoscope which is used in medical applications should have the total diameter less than 1 mm. Its image resolution is limited to 30∼40 lp/mm. Therefore, the image resolution is one of the most important factors to decide image quality of the ophthalmic endoscopic images. This study obtained high resolution and magnifying ophthalmic endoscopic images by a new optical design using a 0.23 pitch GRIN lens and high resolution fiber-optic image guide which has less than 5 ${\mu}{\textrm}{m}$ diameter microfibers. The resolutions of images from existing and from a new type of ophthalmic endoscope are measured and compared using a USAF resolution target.

Pattern of Sexual Dimorphism in Garcinia kola (Heckel) Plantation

  • Henry Onyebuchi, Okonkwo;Godwin Ejakhe, Omokhua;Uzoma Darlington, Chima
    • Journal of Forest and Environmental Science
    • /
    • v.38 no.4
    • /
    • pp.275-283
    • /
    • 2022
  • A study was designed to investigate the pattern of sexual dimorphism in a plantation of Garcinia kola. Twenty trees were randomly selected for the study and have been observed to flower regularly. A total of 100 inflorescence were randomly collected from the crown of each tree and 500 flowers randomly assessed within the period of four (4) flowering seasons. Floral sex assessment was done visually and with a hand magnifying lens; floral morphometric measurements (i.e. pedicel and perianth length and breadth), inflorescence length, and breadth) was taken using a veneer caliper; number of flowers per inflorescence and inflorescence per twig was counted; while, data analysis was conducted on excel using analysis of variance and pairwise t-test comparison. Four floral sexes were identified in the G. kola plantation studied which were unisexual male flowers, unisexual female flowers, cosexual unisexual male flowers, and cosexual hermaphrodite flowers. Three tree sexes were identified viz: inconstant male, invariant female, and cosexual trees. The plantation was significantly sexually dimorphic in floral sex and phenotypic traits (i.e. pedicel and perianth size), and as well as sexually dimorphic in tree sex and reproductive phenotypic traits (i.e. inflorescence size, number of inflorescences per twig, and number of flower bud per inflorescence). The sexual system of the plantation was therefore trioecious with features suggestive of evolving dioecy through the gynodioecious pathway.

Development of Automatic Nut Inspection System using Image Processing (이미지 프로세싱을 이용한 자동 너트 검사 장비 개발)

  • Lee, Sang-Hak;Seo, Myong-Ho;Chung, Tae-Choong
    • The KIPS Transactions:PartA
    • /
    • v.11A no.4
    • /
    • pp.235-242
    • /
    • 2004
  • When manufacturing information and communication device that consists of lots of part, it is important to improve the quality of the produced system by inspecting the system accurately and exclude the defected part. In case of LCD which is recently in a great demand, the inspection process of the nut which bonds the back frame to protect the LCD panel has to be done by human labor. It highly required an automatic inspection system which can inspect the nut without wasting human resources. In this paper, we describe the process of developing a system which automatically inspect the status of nuts inserted during the manufacturing of LCD. The nut inspection vision system developed measures the number of nut's spiral, the distance between pitches, the width of a pitch, and the inside diameter of nut. We have adopted lens with high magnifying power and calibration tool and intended to produce automatic lighting for maintaining a stable environment for a high precision system. We also developed the algorithms for analyzing the nut. We apply the system to real factory field and verify that it is better than the man power in terms of error rate.

Correlation Between Korean Healthy Women's Skin Condition and Sasang Constitution (건강한 한국 성인 여성의 피부 상태와 사상체질과의 상관성에 관한 연구)

  • 이수경;남경애;선보경;김상복;송일병
    • The Journal of Korean Medicine
    • /
    • v.25 no.1
    • /
    • pp.161-171
    • /
    • 2004
  • Objectives: Sasang Constitutional Medicine is popularly appliedto treatment in Korea. Constitution is a holistic concept contained internal and external characteristics, and physical traits including ordinary symptoms. Skin is one of constitutional property elements. So we researched a correlation female facial skin and sasang constitution. This is a basic study to find constitution can be a major factor to care and manage skin. Methods: We examined sasang constitution and facial skin condition of 100 healthy women who aged from 30 to 59. Hydration and sebum of facial skin was measured by skin diagnostic instrument and skin type was calculated from the data. Keratin, pore size, acne, and brightness of face was measured by skin magnifying lens and subjective skin troubles in ordinary times was also investigated. Constitution diagnosis and Skin diagnosis was investigated separately as a blind test andthe data was statistically analyzed with chi-square test, Correlation analysis, One-way analysis of variance. Results: 1. In sasang constitution, Taeeumingroup bad significant tendencies of larger hydration and sebum amount, combination degree of forehead and cheek was also higher than other constitutions(p<0.05). 2. Facial skin type was significantly different according to Sasang Constitution, Soeumin and Soyangin had a tendency of dry skin comparatively, but Taeeumin had mainly a tendency of combination skin and secondly dry skin(p<0.05). On the other hand, there was no correlation between age and skin type. 3. In subjective skin trouble, Soeumin group had less acne trouble than Soyangin and Taeeumin group(p<0.1). Pore size trouble was more frequent in Soyangin group than Soeumin group(p<0.05). Keratin trouble was more frequent in Soeumin group than Soyangin and Taeumin group(p<0.1). Conclusions: Korean healthy women's skin condition was different according to sasang constitution.

  • PDF

The Investigation on the Observation Ability of Elementary School Student about the Grasshopper(Oxya chinesis) (메뚜기를 이용한 초등학교 학생들의 관찰 능력 조사)

  • 한광래
    • Journal of Korean Elementary Science Education
    • /
    • v.22 no.1
    • /
    • pp.121-129
    • /
    • 2003
  • The enhancement of inquiry skills has been emphasized as a important objective of science education for a long time. Of these, the observation is not only a simple and basic skill, but also a very important skill, in aspect of gathering informations about the nature of all things around us, through interaction between the sense organs of body and objectives. The purpose of this study is to investigate the results of observations about the grasshopper(Oxya chinesis), made by the elementary student from the 3rd to the 6th grade, and to make use of them as the basic materials for the observative teaming and the evaluation of the observation ability. Through this study, the collected items of observation are as follows For grasshopper, a total of observation items is 95, 70 using the sight sense, 13 using the tactile sense,7 using the olfactory sense. 3 using the palate sense and 2 using the auditory sense. In this study, the findings of elementary student's observation are as follows. 1. On the whole, most of students have observed mainly by the sight and the tactile sense, when observing the grasshopper. 2. It is showed a tendency that the observation ability of student is increased with the higher grade in elementary school. 3. As the grade ascends. the observations with operating are increased, also the quantitative expression and interpretation about them are increased. 4. In the case of same grade, there is no significant difference between students' gender, though girls' ability of the observation showed somewhat higher than boys' 5. Occasionally, the interpretations on the observative facts made by student, are inaccurate. Basis on the above results, we suggested some directions for the improvement of the observative learning program in science classroom of elementary school. First, the teacher have to serve as a guide and encouragement in the observative learning class, to be accomplished the various observation, which all the sensory organ can be used by student than the sight sense. Second, to get elevated the ability of observation, it is necessary that some experimental tools(magnifying lens, stereoscope, auxiliary implements etc.) are utilized. Third, the teacher have to make often endeavors showing an example of operation, to be activated the atmosphere of operative observation.

  • PDF