• Title/Summary/Keyword: first occurrence

Search Result 1,690, Processing Time 0.024 seconds

Occurrence of scutica-like ciliate (SLC) and its control during the mass seed production of the Japanese scallop, Patinopecten yessoensis (참가리비 (Patinopecten yessoensis) 대량 종묘생산시의 Scutica-like ciliate 발생 및 대책)

  • Jo, Q-Tae;Bang, Jong-Deuk;Kim, Su-Kyeong;Rahman, Mohamad M.;Gong, Yong-Geun;Kim, Dae-Kwon;Lee, Joo-Seok
    • Journal of fish pathology
    • /
    • v.21 no.3
    • /
    • pp.167-174
    • /
    • 2008
  • Few studies on parasitic scutica-like ciliates (SLCs) influencing larval growth and survival during the seed production of the Japanese scallop, Patinopecten yessoensis have been performed in spite of relatively high magnitude of their infectious damage to the larvae. In the mass seed production of the scallop, SLCs were never infectious during D-larval stage which lasted 6 to 7 days. Indeed, the infection first occurred in 2 to 4 days after first umbo-staged larvae. A regular selection of active larvae in swimming behavior kept larval SLC infection low throughout the culture compared to unselected control (P<0.05) in which all the larvae alive were contained. Higher infection frequencies of the unselected control resulted in lower larval survivals and wider range of larval size distribution that drove larval attachment rate lower. To the worse, the nursery spats from the higher SLC infection exhibited a retarded growth and elevated occurrence of abnormal scallop.

Occurrence and Characterization of Leaf Spot Caused by Septoria melissae on Lemon Balm in Korea

  • Yang, Seon-Ah;Choi, In-Young;Ju, Ho-Jong;Lee, Kui-Jae;Galea, Victor;Shin, Hyeon-Dong
    • Mycobiology
    • /
    • v.48 no.6
    • /
    • pp.495-500
    • /
    • 2020
  • Leaf spot on lemon balm is frequently observed in Korea, causing considerable damage to crops. In 2014 and 2015, the occurrence of leaf spot was observed in several production greenhouses at Suwon, Gongju, and Namwon in Korea. Symptoms on lower leaves initially developed as small, distinct, discolored lesions, which enlarged progressively turning into dark brown, angular spots surrounded by purplish-brown margins. Based on the morphological characteristics and sequence analysis of actin (ACT), translation elongation factor 1-alpha (EF-1α), internal transcribed spacer (ITS), 28S nrDNA (LSU), and RNA polymerase II second largest subunit (RPB2), the fungus associated with the lemon balm leaf spot was determined as Septoria melissae. To the best of our knowledge, this is the first report of lemon balm leaf spot caused by S. melissae in Asia as well as in Korea.

The Improvement of Summer Season Precipitation Predictability by Optimizing the Parameters in Cumulus Parameterization Using Micro-Genetic Algorithm (마이크로 유전알고리즘을 이용한 적운물리과정 모수 최적화에 따른 여름철 강수예측성능 개선)

  • Jang, Ji-Yeon;Lee, Yong Hee;Choi, Hyun-Joo
    • Atmosphere
    • /
    • v.30 no.4
    • /
    • pp.335-346
    • /
    • 2020
  • Three free parameters included in a cumulus parameterization are optimized by using micro-genetic algorithm for three precipitation cases occurred in the Korea Peninsula during the summer season in order to reduce biases in a regional model associated with the uncertainties of the parameters and thus to improve the predictability of precipitation. The first parameter is the one that determines the threshold in convective trigger condition. The second parameter is the one that determines boundary layer forcing in convective closure. Finally, the third parameter is the one used in calculating conversion parameter determining the fraction of condensate converted to convective precipitation. Optimized parameters reduce the occurrence of convections by suppressing the trigger of convection. The reduced convection occurrence decreases light precipitation but increases heavy precipitation. The sensitivity experiments are conducted to examine the effects of the optimized parameters on the predictability of precipitation. The predictability of precipitation is the best when the three optimized parameters are applied to the parameterization at the same time. The first parameter most dominantly affects the predictability of precipitation. Short-range forecasts for July 2018 are also conducted to statistically assess the precipitation predictability. It is found that the predictability of precipitation is consistently improved with the optimized parameters.

A Study on a Countermeasure Program using the Martial Arts for a Security Guard Caused by an Accidental Situation (우발상황시 경호무도 대응방안)

  • Park, Jun-Seok;Kang, Young-Gil
    • Korean Security Journal
    • /
    • no.6
    • /
    • pp.327-340
    • /
    • 2003
  • As a countermeasure under accidental occurrence situation, First, as application form of martial arts, A security guard foster ability that can protect a target person of guard and own body under accidental occurrence situation through incessant martial arts practice. To achieve this purpose, incessant training mental power and physical strength reinforcement should be kept on to prevent, therefore make a safety control function for such as weapon, small arms, explosive, vehicles terror etc. happened under accidental occurrence situation. Second, according to the contents of training based on the classification category of martial arts for security guard under accidental situation, a security guard must keep safety distance necessarily lest a target person of gurad should be attacked by attacker, therefore, intercept an attack opportunity if a safety distance between a target person of guard and attacker is not kept. Third, It is to practice confrontation techniques based on the type of attack. A security guard must develp situation disposal ability that can cope properly with the attack using empty hands, murderous weapon, small arms, explosive by case or individual or mass of threat that impose danger and injury in a target person's body of guard.

  • PDF

A Study on the Condensation Performance of Curtain-wall Window in High-Rise Residential Building (초고층 주거건물 커튼월의 창호부 결로 성능평가에 관한 연구)

  • Seok Ho-Tae;Chung Man-Seok;Kwak Hyun-Chul;Kwon Jong-Wook
    • Journal of the Korean housing association
    • /
    • v.16 no.4
    • /
    • pp.81-89
    • /
    • 2005
  • The purpose of this thesis is thermal performance simulation about various type that can apply in the high-rise residential building to estimate condensation performance of window that is consisted of frame and glazing in curtain wall. The result of this thesis are summarized as follows. First, condensation occurrence point when relative humidity is $30{\cdot}40{\cdot}50\%$ is shortest Low-e double glass. Difference by type of gas and spacer was a little by $2{\~}6$ cm, among it, the case that apply krypton in gas and the case that apply double seal in spacer were less condensation occurrence distribution. Second, when analyzed improved proposal of window and existing plan through simulation, improved proposal is superior from general side of the interior and exterior temperature, thermal break surrounding temperature and temperature of frame end, condensation occurrence point etc. Therefore, if it was used improved proposal with effect that improve in curtain wall of high-rise residential building, it may improve window condensation performance of curtain wall.

Secured Verification of Intrusion Prevention System Security Model Based on CPNs (CPN 기반의 침입방지시스템 보안모델의 안정성 검증)

  • Lee, Moon-Goo
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.48 no.3
    • /
    • pp.76-81
    • /
    • 2011
  • Intrusion prevention systems (IPS) are important solution about solved problems for inside system security or outsider attacks. When introduce this system, first consideration item is secured rather than multiple function. Colored Petri Nets (CPNs) used that in order to secured verification for user authentication function of intrusion prevention system security model. CPNs is a graphical modeling language suitable for modeling distributed, concurrent, deterministic or non-deterministic systems with synchronous. Like these CPNs was expressed every possible state and occurrence graph. Secured of IPS security model was verified because expression every state using CPN tool and as a result of analyzing the occurrence graph was without a loop or interruption.

Hybrid Damage Monitoring Technique for Plate Girder Bridges using Acceleration-Impedance Signatures (판형교의 가속도-임피던스 신호를 이용한 하이브리드 손상 모니터링 기법)

  • Hong, Dong-Soo;Cho, Hyun-Man;Na, Won-Bae;Kim, Jeong-Tae;Park, Gyu-Hae
    • Proceedings of the Computational Structural Engineering Institute Conference
    • /
    • 2008.04a
    • /
    • pp.197-202
    • /
    • 2008
  • In this paper, a hybrid vibration-impedance approaches is newly proposed to detect the occurrence of damage, the location of damage, and extent of damage in steel plate-girder bridges. The hybrid scheme mainly consists of three sequential phases: 1) to alarm the occurrence of damage, 2) to classify the alarmed damage, and 3) to estimate the classified damage in detail. Damage types of interest include flexural stiffness-loss in girder and bolts-loose in supports. In the first phase, the global occurrence of damage is alarmed by monitoring changes in acceleration features. In the second phase, the alarmed damage is classified into subsystems by recognizing patterns of impedance features. In the final phase, the location and the extent of damage are estimated by using modal strain energy-based damage index method and root mean square deviation method. The feasibility of the proposed system is evaluated on a laboratory-scaled steel plate-girder bridge model for which hybrid vibration-impedance signatures were measured for several damage scenarios.

  • PDF

Seoul, Keep Your Paddies! Implications for the Conservation of Hylid Species

  • Borzee, Amael;Ahn, Jaeha;Kim, Sanha;Heo, Kyongman;Jang, Yikweon
    • Animal Systematics, Evolution and Diversity
    • /
    • v.31 no.3
    • /
    • pp.176-181
    • /
    • 2015
  • Biodiversity is plummeting worldwide, and the major causes of such decline include habitat degradation and climate change. While cities do contribute to the negative impact to the environment, they can also serve as strategic centres for conservation programs. Sites qualifying as biogeographic islands within metropolitan Seoul were studied for the occurrence of two hylid species: the endangered Hyla suweonensis and the abundant H. japonica. This study demonstrates that neither habitat diversity nor surface area, but solely the occurrence of aggregated rice paddies is a requisite for H. suweonensis, hypothetically due to its strict breeding requirements. On the contrary, H. japonica occurrence was not affected by any of these factors, and all types of habitats studied were adequate for this species. The presence of an endangered species within the boundaries of one of the most populated metropolises suggests a strong natural resilience, which should be enhanced with appropriate actions. We emphasize that the management plans therein can, and should, be used as the first step in the conservation of H. suweonensis in metropolitan Seoul.

Developing Accident Models of Rotary by Accident Occurrence Location (로터리 사고발생 위치별 사고모형 개발)

  • Na, Hee;Park, Byung-Ho
    • International Journal of Highway Engineering
    • /
    • v.14 no.4
    • /
    • pp.83-91
    • /
    • 2012
  • PURPOSES : This study deals with Rotary by Accident Occurrence Location. The purpose of this study is to develop the accident models of rotary by location. METHODS : In pursuing the above, this study gives particular attentions to developing the appropriate models using multiple linear, Poisson and negative binomial regression models and statistical analysis tools. RESULTS : First, four multiple linear regression models which are statistically significant(their $R^2$ values are 0.781, 0.300, 0.784 and 0.644 respectively) are developed, and four Poisson regression models which are statistically significant(their ${\rho}^2$ values are 0.407, 0.306, 0.378 and 0.366 respectively) are developed. Second, the test results of fitness using RMSE, %RMSE, MPB and MAD show that Poisson regression model in the case of circulatory roadway, pedestrian crossing and others and multiple linear regression model in the case of entry/exit sections are appropriate to the given data. Finally, the common variable that affects to the accident is adopted to be traffic volume. CONCLUSIONS : 8 models which are all statistically significant are developed, and the common and specific variables that are related to the models are derived.

Risk Evaluation in FMEA when the Failure Severity Depends on the Detection Time (FMEA에서 고장 심각도의 탐지시간에 따른 위험성 평가)

  • Jang, Hyeon Ae;Yun, Won Young;Kwon, Hyuck Moo
    • Journal of the Korean Society of Safety
    • /
    • v.31 no.4
    • /
    • pp.136-142
    • /
    • 2016
  • The FMEA is a widely used technique to pre-evaluate and avoid risks due to potential failures for developing an improved design. The conventional FMEA does not consider the possible time gap between occurrence and detection of failure cause. When a failure cause is detected and corrected before the failure itself occurs, there will be no other effect except the correction cost. But, if its cause is detected after the failure actually occurs, its effects will become more severe depending on the duration of the uncorrected failure. Taking this situation into account, a risk metric is developed as an alternative to the RPN of the conventional FMEA. The severity of a failure effect is first modeled as linear and quadratic severity functions of undetected failure time duration. Assuming exponential probability distribution for occurrence and detection time of failures and causes, the expected severity is derived for each failure cause. A new risk metric REM is defined as the product of a failure cause occurrence rate and the expected severity of its corresponding failure. A numerical example and some discussions are provided for illustration.