• Title/Summary/Keyword: exposed region

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X-ray Image Processing for the Korea Red Ginseng Inner Hole Detection ( I ) - Preprocessing technique for inner hole detection - (홍삼 내공검출을 위한 X-선 영상처리기술(I) - 내공검출에 적합한 전처리기법 -)

  • 손재룡;최규홍;이강진;최동수;김기영
    • Journal of Biosystems Engineering
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    • v.27 no.4
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    • pp.341-348
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    • 2002
  • Quality evaluation of red ginsengs is determined by outer shape and inner qualities. Especially, the inner qualities are main grading criteria. Currently, red ginsengs are classified into 3-grades; heaven, earth and good. The best heaven grade must not include inner holes and sponge tissues. This study was conducted to develop a red ginseng sorting system using x-ray image processing technique. Because of lens characteristic, gray values of the central region in the x-ray image are higher and gradually decreased towards the edge regions. This difference of gray values gives trouble in segmentation and detection of inner holes in red ginseng image, so preprocessing technique is necessary. The preprocessing was done by subtracting source image from an empty background image. But, simple subtraction was not quite appropriate because of too small contrast between inner holes and sound part. Scaled subtraction images were obtained by multiplying all gray values by some numbers. However this method could not help to set threshold value because the gray values of root part are generally lower than body part when red ginseng is exposed to the x-ray. To determine threshold value for detecting inner holes, an algorithm was developed by increasing overall gray values of less clear images.

Piracy: Its Nature, Development and Countermeasures (해적행위의 본질, 발생현황 및 조직.기술적 대응 방안에 관한 연구)

  • 최진태
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.4 no.2
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    • pp.69-83
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    • 1998
  • Sea transportation has long been a vital component of the transport systems of the world. The great majority of imports and exports to and enlarge their national merchant marines. This effort is meant partly to arrest earlier trends of having their trade carried by ships from outside the region and partly to promote regional integration and improve the national balance of payments. However, sea transportation has been exposed to various types of threats on the high seas, in coastal waters and in port areas. Piracy is any robbery or other violent action, for private ends and without authorization by public authority, committed on the seas. Because piracy has been regarded as an offense against the law of nations, the public vessels of any state have been permitted to seize a pirate ship, to bring it into port, to try the crew(regardless of their nationality or domicile), and, if found guilty, to punish them and to confiscate the ship. Piracy has occurred in all stages of maritime history. The increased size of merchant vessels, the improved naval patrolling of most ocean highways, the regular administration of most islands and land areas of the world, and the general recognition by governments of piracy as an international offense resulted in a great decline in piracy in the 19th and 20th centuries. Piracy has, however, occurred in the 20th century, and the practice of hijacking ships has developed into a new form of piracy. The number of incidents of sea piracy against ships reported was 229 in 1997. Since 1991, 1,051 such acts have been reported. The purpose of this research is to examine the origin and development of the piracy to understand the current situation of such violence on the seas. In addition, what should be done by international community will be presented to prevent the piracy in the future.

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Highly Flexible Touch Screen Panel Fabricated with Silver Nanowire Crossing Electrodes and Transparent Bridges

  • Jeon, Youngeun;Jin, Han Byul;Jung, Sungchul;Go, Heungseok;Lee, Innam;Lee, Choonhyop;Joo, Young Kuil;Park, Kibog
    • Journal of the Optical Society of Korea
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    • v.19 no.5
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    • pp.508-513
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    • 2015
  • A capacitive-type touch screen panel (TSP) composed of silver nanowire (AgNW) crossing electrodes and transparent bridge structures was fabricated on a polycarbonate film. The transparent bridge structure was formed with a stack of Al-doped ZnO (AZO) electrodes and SU-8 insulator. The stable and robust continuity of the bridge electrode over the bridge insulator was achieved by making the side-wall slope of the bridge insulator low and depositing the conformal AZO film with atomic layer deposition. With an extended exposure time of photolithography, the lower part of the SU-8 layer around the region uncovered by the photomask can be exposed enough to the UV light scattered from the substrate. This leads to the low side-wall slope of the bridge insulator. The fabricated TSP sample showed a large capacitance change of 22.71% between with and without touching. Our work supplies the technological clue for ensuring long-term reliability to the highly flexible and transparent TSP made by using conventional fabrication processes.

Improved Resistance to Oxidative Stress by a Loss-of-Function Mutation in the Arabidopsis UGT71C1 Gene

  • Lim, Chae Eun;Choi, Jung Nam;Kim, In A;Lee, Shin Ae;Hwang, Yong-Sic;Lee, Choong Hwan;Lim, Jun
    • Molecules and Cells
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    • v.25 no.3
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    • pp.368-375
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    • 2008
  • Approximately 120 UDP-glycosyltransferases (UGTs), which are classified into 14 distinct groups (A to N), have been annotated in the Arabidopsis genome. UGTs catalyze the transfer of sugars to various acceptor molecules including flavonoids. Previously, UGT71C1 was shown to glycosylate the 3-OH of hydroxycinnamates and flavonoids in vitro. Such secondary metabolites are known to play important roles in plant growth and development. To help define the role of UGT71C1 in planta, we investigated its expression patterns, and isolated and characterized a loss-of-function mutation in the UGT71C1 gene (named ugt71c1-1). Our analyses by quantitative real-time reverse transcriptase polymerase chain reaction (qRT-PCR), microarray data mining, and histochemical detection of GUS activity driven by the UGT71C1 promoter region, revealed the tissue-specific expression patterns of UGT71C1 with highest expression in roots. Interestingly, upon treatment with methyl viologen (MV, paraquat), ugt71c1-1 plants displayed enhanced resistance to oxidative stress, and ROS scavenging activity was higher than normal. Metabolite profiling revealed that the levels of two major glycosides of quercetin and kaempferol were reduced in ugt71c1-1 plants. In addition, when exposed to MV-induced oxidative stress, eight representative ROS response genes were expressed at lower levels in ugt71c1-1 plants, indicating that ugt71c1-1 probably has higher non-enzymatic antioxidant activity. Taken together, our results indicate that ugt71c1-1 has increased resistance to oxidative stress, suggesting that UGT71C1 plays a role in some glycosylation pathways affecting secondary metabolites such as flavonoids in response to oxidative stress.

JND based Illumination and Color Restoration Using Edge-preserving Filter (JND와 경계 보호 평탄화 필터를 이용한 휘도 및 색상 복원)

  • Han, Hee-Chul;Sohn, Kwan-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.46 no.6
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    • pp.132-145
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    • 2009
  • We present the framework for JND based Illumination and Color Restoration Using Edge-preserving filter for restoring distorted images taken under the arbitrary lighting conditions. The proposed method is effective for appropriate illumination compensation, vivid color restoration, artifacts suppression, automatic parameter estimation, and low computation cost for HW implementation. We show the efficiency of the mean shift filter and sigma filter for illumination compensation with small spread parameter while considering the processing time and removing the artifacts such as HALO and noise amplification. The suggested CRF (color restoration filter) can restore the natural color and correct color distortion artifact more perceptually compared with current solutions. For the automatic processing, the image statistics analysis finds suitable parameter using JND and all constants are pre-defined. We also introduce the ROI-based parameter estimation dealing with small shadow area against spacious well-exposed background in an image for the touch-screen camera. The object evaluation is performed by CMC, CIEde2000, PSNR, SSIM, and 3D CIELAB gamut with state-of-the-art research and existing commercial solutions.

Evaluation of the Lip during Smile in Normal Occlusion Adults (정상교합자의 미소시 구순 형태에 관한 연구)

  • Chi, Kuk-Sop;Kim, Kwang-Won
    • The korean journal of orthodontics
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    • v.26 no.2 s.55
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    • pp.197-204
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    • 1996
  • This study was performed to mark the criteria of the eathetic smile that was necessary to improve the esthetic problem in oral maxillo-facial region. The facial straight photographs of 62 adults(30 males, 32 females : 19-24 years old) in resting position and during smile were taken. The measurements and proportion of lip-teeth relationship during smile were statistically analyzed with photogrammetry. The following results wow obtained : 1. In the evaluation of the change of lips, smile line ratio was 0.93, buccal corridor ratio was 0.63, and smile symmetry ratio was 0.96. 2. The width of mouth during smile was 1.31 times of the width inthe resting position and 0.48 times of face width. 3. The upper lip height during smile was 0.69 times of the height in the resting position and the lower lip height during smile was 0.93 times of the height in the resting position. 4. The mean exposed lenght of upper central incisor was 9.96mm. Maxillary incisor exposure was significantly correlated with the upper lip change ratio, mouth width change ratio, and buccal corridor ratio.

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A Study on Prediction Model of Chloride ion Permeation of Cement Mortar by Steel Powder (염해환경에서의 염화물이온 침투 예측에 관한 연구)

  • Kim, Jeong-Jin;Park, Soon-Jeon;Ko, Joo-Hwan;Han, Cheon-Goo
    • Proceedings of the Korea Concrete Institute Conference
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    • 2008.04a
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    • pp.513-516
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    • 2008
  • In this study the prediction model of Chloride Ion progress rate of concrete using steel powder as an addition is developed, in which the reduction of not only the diffusion rate of $Cl^-$ but also the corrosion rate by replenishment of pore by corrosion products. The model is based on the diffusions of $Cl^-$ and its reaction with $Fe^{2+}$, in chloride attack progression region. The model can also explain the characteristics of chloride ion permeation resistance of concrete that the matrix is densified due to corrosion products. The prediction by the model agreed well the experimental data in which the concrete using steel powder, and it showed the lower rate in long-term age to Chloride Ion progress rate than the concrete without steel powder. Consequently the model can predict Chloride Ion progress rate of concrete exposed in the atmosphere regardless of the water-to-cement raito, the amount of the content of steel powder, etc.

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Analysis of the Bioheat Equation Considering Tissue Layers with Sinusoidal Temperature Oscillation on the Skin (사인 주기의 온도 변화가 가해지는 피부 조직의 생체열 방정식에 대한 해석)

  • Choi, Woo-Lim;Moon, Sang-Don;Youn, Suk-Bum;Im, Ik-Tae
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.35 no.8
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    • pp.757-762
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    • 2011
  • We investigate the transient temperature response in biological tissue whose surface is exposed to alternately varying sinusoidal oscillation. Based on the Pennes bio-heat equation, we apply numerical analysis using a finite element method to find the effects of the physical properties of the skin layers. Three layers of tissue-epidermis, dermis, and subcutaneous-are considered as the solution region. We investigate the effects of different properties of the skin layers on the temperature profile. We also investigate the effects of the perfusion rate for the dermis, which is the most sensitive layer. The results show that the temperature profile of tissue depth has a discontinuous point when different physical properties are used.

Natural Frequency Analysis of Cantilever Plates with Added Mass (부가수 질량을 고려한 외팔판의 고유진동 해석)

  • Jang, Hyun-Gil;Nho, In Sik;Hong, Chang-Ho;Lee, Chang-Sup
    • Journal of the Society of Naval Architects of Korea
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    • v.50 no.1
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    • pp.1-7
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    • 2013
  • The high-skewed and/or composite propellers of current interests to reduce the ship vibration and to increase the acoustic performance are likely to be exposed to the unexpected structural problems. One typical example is that the added mass effect on the propellers working in the non-uniform wake field reduces the natural frequency of the propeller leading to the resonance with the low-frequency excitation of the external forces. To avoid this resonance problem during the design stage, the technique of fluid-structure interaction has been developed, but the higher-order effect of the blade geometry deformation is not yet considered in evaluating the added mass effects. In this paper the fluid boundary-value problem is formulated by the potential-based panel method in the inviscid fluid region with the velocity inflow due to the body deformation, and the structural response of the solid body under the hydrodynamic loading is solved by applying the finite element method which implements the 20-node iso-parametric element model. The fluid-structure problem is solved iteratively. A basic fluid-sturcture interaction study is performed with the simple rectangular plates of thin thickness with various planform submerged in the water of infinite extent. The computations show good correlation with the experimental results of Linholm, et al. (1965).

Estimation method of heat flux at tube bank exposed to high temperature flue gas in large scale coal fired boilers (보일러 내부 고온가스에 노출된 전열 튜브에서의 열유속 평가 방법)

  • Jung, Jae-Jin;Song, Jung-Il
    • 한국태양에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.259-264
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    • 2009
  • Most of the fossil power plants firing lower grade coals are challenged with maintaining good combustion conditions while maximizing generation and minimizing emissions. In many cases significant derate, availability losses and increase in unburned carbon levels can be attributed to poor combustion conditions as a result of poorly controlled local fuel and air distribution within the boiler furnace. The poor combustion conditions are directly related to the gas flow deviation in upper furnace and convection tube-bank but a less reported issue related to in large-scale oppose wall fired boilers. In order to develop a on-line combustion monitoring system and suggest an alternative heat flux estimation method at tube bank, which is very useful information for boiler design tool and blower optimizing system, field test was conducted at operating power boiler. During the field test the exhaust gases' temperature and tube metal temperature were monitored by using a spatially distributed sensors grid which located in the boiler's high temperature vestibule region. At these locations. the flue gas flow is still significantly stratified, and air in-leakage is minimal which enables tracing of poor combustion zones to specific burners and over-fire air ports. Test results showed that the flue gas monitoring method is more proper than metal temperature distribution monitoring for real time combustion monitoring because tube metal temp. distribution monitoring method is related to so many variables such as flue gas, internal flow unbalance, spray etc., Heat flux estimation at the tube bank with flue gas temp. and metal temp. data can be alternative method when tube drilling type sensor can't able to use.

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