• Title/Summary/Keyword: K252a

Search Result 1,580, Processing Time 0.032 seconds

Methodology for Extracting Trap Depth using Statistical RTS Noise Data of Capture and Emission Time Constant

  • Oh, Dong-Jun;Kwon, Sung-Kyu;Song, Hyeong-Sub;Kim, So-Yeong;Lee, Ga-Won;Lee, Hi-Deok
    • JSTS:Journal of Semiconductor Technology and Science
    • /
    • v.17 no.2
    • /
    • pp.252-259
    • /
    • 2017
  • In this paper, we propose a novel method for extracting an accurate depth of a trap that causes RTS(Random Telegraph Signal) noise. The error rates of the trap depth rely on the mean time constants and its ratio. Here, we determined how many data of the capture and emission time constant are necessary in order to reduce the trap depth error caused by an inaccurate mean time constant. We measured the capture and emission time constants up to 100,000 times in order to ensure that the samples had statistical meaning. As a result, we demonstrated that at least 1,000 samples are necessary to satisfy less than 10% error for trap depth. This result could be used to improve the accuracy of RTS noise analysis.

A Study on K-Inverter Characteristics for Triple E-Plane type Structures (삼중 E-평면형 구조의 K-인버터특성에 관한 연구)

  • 오영주
    • Proceedings of the Optical Society of Korea Conference
    • /
    • 1990.02a
    • /
    • pp.252-256
    • /
    • 1990
  • In this paper, we proposed E-plane structures to obtain the high insertion loss at stopband and show that T-equivalent and K-inverter of Triple E-plane structures are better than those of All-Metal Insert E-plane structures. To show the characteristics first order bandpass filter are designed and tested at X band.

  • PDF

The Trends of Radiation Research Grasped at IRPA 7 Congress (제7차 IRPA 국제학회를 통해 본 방사선 연구동향)

  • Hwang, Sun-Tae
    • Journal of Radiation Protection and Research
    • /
    • v.13 no.1
    • /
    • pp.42-54
    • /
    • 1988
  • Overall reviews of papers presented at the seventh IRPA International Congress (Aprill 10-17, 1988) held in Sydney, Australia have been done in order to grasp the trends of radiation research. In this report, the changing and increasing matters in the field of ionizing radiation safety as well as non-ionizing radiation application are introduced to the KARP. In addition, a research paper, 'Emission Rate Measurement of a Cf-252 Neutron Source by Manganous Sulfate Bath Method', presented at the IRPA 7 Poster Session is followed.

  • PDF

A Study on Ship Path Planning Algorithm based on Real-time Ocean Environment (실해역 환경을 고려한 선박의 최적항해계획 알고리즘 연구)

  • Kim, Dongjun;Seol, Hyeonju;Kim, Jinju
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.19 no.2
    • /
    • pp.252-260
    • /
    • 2016
  • Unlike terrestrial transportation, marine transportation should consider environment factors in order to optimize path planning. This is because, ship's path planning is greatly influenced by real-time ocean environment-sea currents, wave and wind. Therefore, in this study, we suggest a ship path planning algorithm based on real-time ocean environment using not only $A^*$ algorithm but also path smoothing method. Moreover, in order to improve objective function value, we also consider ship's moving distance based on ship's location and real-time ocean environment data on grid map. The efficiency of the suggested algorithm is proved by comparing with $A^*$ algorithm only. This algorithm can be used as a reasonable automatics control system algorithm for unmaned ship.

Painless Dissecting Aneurysm of the Aorta Presenting as Simultaneous Cerebral and Spinal Cord Infarctions

  • Kwon, Jae-Yoel;Sung, Jae-Hoon;Kim, Il-Sup;Son, Byung-Chul
    • Journal of Korean Neurosurgical Society
    • /
    • v.50 no.3
    • /
    • pp.252-255
    • /
    • 2011
  • Authors report a case of a painless acute dissecting aneurysm of the descending aorta in a patient who presented with unexplained hypotension followed by simultaneous paraplegia and right arm monoparesis. To our knowledge, case like this has not been reported previously. Magnetic resonance imaging of the brain and spine revealed hemodynamic cerebral infarction and extensive cord ischemia, respectively. Computerized tomography angiography confirmed a dissecting aneurysm of the descending aorta. The cause of the brain infarction may not have been embolic, but hemodynamic one. Dissection-induced hypotension may have elicited cerebral perfusion insufficiency. The cause of cord ischemia may be embolic or hemodynamic. The dissected aorta was successfully replaced into an artificial patch graft. The arm monoparesis was improved, but the paraplegia was not improved. In rare cases of brain and/or spinal cord infarction caused by painless acute dissecting aneurysm of the aorta, accurate diagnosis is critical because careless thrombolytic therapy can result in life-threatening bleeding.

Comparison of Vegetation Structure Change between 2003 and 2014 in Forest Fire Damaged Area of Bihwajin Basin, Samcheok in Korea (삼척 비화진 유역 산불피해지의 2003년도와 2014년도의 식생구조 비교)

  • Song, Ju Hyeon;Lim, Joo Hoon;Kwon, Jino;Yun, Chung Weon
    • Journal of Korean Society of Forest Science
    • /
    • v.106 no.2
    • /
    • pp.150-168
    • /
    • 2017
  • This study was carried out to compare stand structure in Bihwajin basin Samcheok-si, Gangwon-do, Korea for ten years between 2003 and 2014, in which occurred the east coastal forest fire in 2000. Data were collected from 32 quadrates that followed by the analysis of vegetation classification according to plant sociology, importance value by Mclntosh and Curtise, species diversity and similarity index. In the result of vegetation classification, the vegetation unit decreased from 7 units to 4 units, and the number of species groups changed from 11 to 7. As a result of importance value (IV) changes, IV of Quercus mongolica, Q. serrata and Q. variabilis was increased by 6.8%, 5.2% and 2.9% in the order, respectively. However, that of Pinus densiflora was decreased by 2.8%. That of major planted species such as Castanea crenata, Chionanthus retusa, Prunus armeniaca var. ansu, Acer triflorum and Koelreuteria paniculata was reduced. As a result of species diversity, it was increased from 0.252 to 0.287 in tree layer, from 0.252 to 0.434 in subtree layer, and from 1.293 to 1.333 in shrub layer. But that in herb layer was decreased from 1.745 to 1.646. As a result of similarity index, it was 0.78, 0.65, 0.72 and 0.55 by layers that showed most difference in herb stratum. Considering the results, this study would be applied to the ecosystem diagnose and management of forest fire damaged area similar to the investigated area.

Anti-pyretic and anti-inflammatory activity of chloroform extract of Croton roxburghii in standard animal models

  • Sivakumar, T;Rajavel, R;Karthikeyan, D;Duraisamy, R;Srinivasan, K;Kumar, S Suresh;Karki, Subhas S
    • Advances in Traditional Medicine
    • /
    • v.8 no.3
    • /
    • pp.252-259
    • /
    • 2008
  • The chloroform extract of Croton roxburghii (Family: Euphorbiaceae) was evaluated for its antipyretic effects in Brewer's yeast induced hyperthermia in rats. The anti-inflammatory effect of the Croton roxburghii was also evaluated by using carrageenan, dextran, histamine, serotonin induced rat paw oedema and cotton pellet induced granuloma (chronic) models in rats. The chloroform extract of Croton roxburghii (CECR) exhibited significant anti-pyretic and anti-inflammatory effect at the dose 50, 100 and 200 mg/kg. Maximum inhibition (55.32%) was notedat the dose of 200 mg/kg after 3 h of drug treatment in carrageenan induced paw oedema, whereas the Indomethacin (standard drug) produced 61.33% of inhibition. The extract exhibited significant anti-inflammatory activity in dextran induced paw edema in a dose dependent manner. In the chronic model (cotton pellet induced granuloma) the CECR (200 mg/kg) and Indomethacin (10 mg/kg) showed decreased formation of granuloma tissue by 52.32% and 56.32% respectively. The extract also exhibited a significant antipyretic response in Brewer's yeast induced pyrexia in rats. Thus, the present study revealed that the CECR exhibited significant antipyretic and anti-inflammatory activity in the tested animal models.

A Study of Global Manufacturing Education and Training for Chinese Company Manager

  • Sun, Jing;Tamaki, Kin'ya;Yeh, Shihshui;Takiuti, Noboru
    • Industrial Engineering and Management Systems
    • /
    • v.13 no.3
    • /
    • pp.252-257
    • /
    • 2014
  • Global economic recession, global market reduction, and the deteriorating economic recession are forcing the industry to reconsider the business plan and strategy related to supply chain regardless of the size of the companies. During the economic recession caused by financial anxiety, development of international collaborative producer is the key theme for a manufacturing industry to get over the situation. Especially, development of high-skilled people who are capable of handling global manufacturing management is the key factor in China which shifted from a world factory to a world market. In this background, we started the international project of global manufacturing education and training for Chinese company managers from 2009. In this paper, based on the research conducted by the universities and companies in China, a design of global manufacturing education and training is proposed. This presented design is based on the theory of Japanese production strategy and investigation of actual conditions for Chinese companies and the research methodology of business management practice with efficiency and productive for international level management organization. The effectiveness of the education design is evaluated by applying the international education and training project of Aoyama Gakuin Human Innovation Consulting Inc. and Vigor Management Technology Association.

Optical Flow Based Collision Avoidance of Multi-Rotor UAVs in Urban Environments

  • Yoo, Dong-Wan;Won, Dae-Yeon;Tahk, Min-Jea
    • International Journal of Aeronautical and Space Sciences
    • /
    • v.12 no.3
    • /
    • pp.252-259
    • /
    • 2011
  • This paper is focused on dynamic modeling and control system design as well as vision based collision avoidance for multi-rotor unmanned aerial vehicles (UAVs). Multi-rotor UAVs are defined as rotary-winged UAVs with multiple rotors. These multi-rotor UAVs can be utilized in various military situations such as surveillance and reconnaissance. They can also be used for obtaining visual information from steep terrains or disaster sites. In this paper, a quad-rotor model is introduced as well as its control system, which is designed based on a proportional-integral-derivative controller and vision-based collision avoidance control system. Additionally, in order for a UAV to navigate safely in areas such as buildings and offices with a number of obstacles, there must be a collision avoidance algorithm installed in the UAV's hardware, which should include the detection of obstacles, avoidance maneuvering, etc. In this paper, the optical flow method, one of the vision-based collision avoidance techniques, is introduced, and multi-rotor UAV's collision avoidance simulations are described in various virtual environments in order to demonstrate its avoidance performance.

Inhibition of Melanogenesis by Abietatriene from Vitex Trifolia Leaf Oil

  • Lee, Hong Gu;Kim, Tae Yoon;Jeon, Jung Hoon;Lee, Sang Hwa;Hong, Yoon Ki;Jin, Mu Hyun
    • Natural Product Sciences
    • /
    • v.22 no.4
    • /
    • pp.252-258
    • /
    • 2016
  • Vitex trifolia L. has been used traditionally to treat various illnesses, such as inflammation, headache, migraine, and gastrointestinal infections. We analyzed and evaluated the composition of V. trifolia leaf oil. Based on the results, we isolated abietatriene from V. trifolia leaf oil and investigated the effect of V. trifolia leaf oil and its active compound abietatriene on melanogenesis in B16F10 melanoma cells. They significantly decreased melanin contents and melanogenic factors, such as tyrosinase, TRP-1, TRP-2, and MITF dose-dependently in both protein and mRNA levels. Protein and mRNA expressions were determined by Western blot analysis and quantitative real time RT-PCR. Findings indicate that V. trifolia leaf oil and abietatriene reduce melanogenesis by regulating the expression of melanogenic factors. These results suggest that V. trifolia leaf oil and abietatriene could comprise a useful therapeutic agent for treating hyperpigmentation and used as effective skin-whitening agents.