• Title/Summary/Keyword: first occurrence

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A Procedure for Inducing the Occurrence of Rice Seedling Blast in Paddy Field

  • Qin, Peng;Hu, Xiaochun;Jiang, Nan;Bai, Zhenan;Liu, Tiangang;Fu, Chenjian;Song, Yongbang;Wang, Kai;Yang, Yuanzhu
    • The Plant Pathology Journal
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    • v.37 no.2
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    • pp.200-203
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    • 2021
  • Rice blast caused by the filamentous fungus Magnaporthe oryzae, is arguably the most devastating rice disease worldwide. Development of a high-throughput and reliable field blast resistance evaluation system is essential for resistant germplasm screening, resistance genes identification and resistant varieties breeding. However, the occurrence of rice blast in paddy field is easily affected by various factors, particularly lack of sufficient inoculum, which always leads to the non-uniform occurrence and reduced disease severity. Here, we described a procedure for adequately inducing the occurrence of rice seedling blast in paddy field, which involves pretreatment of diseased straw, initiation of seedling blast for the first batch of spreader population, inducing the occurrence of the second batch of spreader population and test materials. This procedure enables uniform and consistent infection, which facilitates efficient and accurate assessment of seedling blast resistance for diverse rice materials.

Prevalence of Accident Occurrence Among Scientific Laboratory Workers of the Public University in Lebanon and the Impact of Safety Measures

  • Nasrallah, Inaam M.;El Kak, Assem K.;Ismaiil, Lina A.;Nasr, Rihab R.;Bawab, Wafa T.
    • Safety and Health at Work
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    • v.13 no.2
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    • pp.155-162
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    • 2022
  • Background: Workers are exposed to several risks in academic laboratories due to the presence of potentially hazardous substances. The main objective of this study was to assess the prevalence of accident occurrence and associated risk factors among laboratory workers at the scientific laboratories of the public university in Lebanon and the impact of safety measures training and availability. Methods: In this observational study, a survey was conducted for one year in scientific laboratories at faculties of the public university. Results: Among the participants (N = 220), 45.0% have had accidents; the main cause was exposure to chemicals (73.7%) and more specifically by inhalation (45.4%). Females (85.9%) were more exposed to accidents than males. Laboratory workers with a master's degree, a full-time schedule, and more than ten years of experience were significantly more exposed to accidents (p < 0.05). A significant association was found between accident occurrence and training on management of hazardous products (p = 0.044), risks related to workplace (p = 0.030), eyewash and emergency shower (p < 0.001), first aid (p = 0.012), and facial protection availability (p = 0.019). In spite of the lack of safety culture and efficient training on laboratory safety, participants have shown a very good perception regarding safety measures to be applied in case of work accidents. Conclusion: Based on our findings, the prevalence of accident occurrence is elevated among lab workers at the public university. The impact of regular training on laboratory safety preventive measures is of great importance to ensure the efficiency of occupational health and safety in scientific laboratories.

An Investigation on Expanding Co-occurrence Criteria in Association Rule Mining (연관규칙 마이닝에서의 동시성 기준 확장에 대한 연구)

  • Kim, Mi-Sung;Kim, Nam-Gyu;Ahn, Jae-Hyeon
    • Journal of Intelligence and Information Systems
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    • v.18 no.1
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    • pp.23-38
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    • 2012
  • There is a large difference between purchasing patterns in an online shopping mall and in an offline market. This difference may be caused mainly by the difference in accessibility of online and offline markets. It means that an interval between the initial purchasing decision and its realization appears to be relatively short in an online shopping mall, because a customer can make an order immediately. Because of the short interval between a purchasing decision and its realization, an online shopping mall transaction usually contains fewer items than that of an offline market. In an offline market, customers usually keep some items in mind and buy them all at once a few days after deciding to buy them, instead of buying each item individually and immediately. On the contrary, more than 70% of online shopping mall transactions contain only one item. This statistic implies that traditional data mining techniques cannot be directly applied to online market analysis, because hardly any association rules can survive with an acceptable level of Support because of too many Null Transactions. Most market basket analyses on online shopping mall transactions, therefore, have been performed by expanding the co-occurrence criteria of traditional association rule mining. While the traditional co-occurrence criteria defines items purchased in one transaction as concurrently purchased items, the expanded co-occurrence criteria regards items purchased by a customer during some predefined period (e.g., a day) as concurrently purchased items. In studies using expanded co-occurrence criteria, however, the criteria has been defined arbitrarily by researchers without any theoretical grounds or agreement. The lack of clear grounds of adopting a certain co-occurrence criteria degrades the reliability of the analytical results. Moreover, it is hard to derive new meaningful findings by combining the outcomes of previous individual studies. In this paper, we attempt to compare expanded co-occurrence criteria and propose a guideline for selecting an appropriate one. First of all, we compare the accuracy of association rules discovered according to various co-occurrence criteria. By doing this experiment we expect that we can provide a guideline for selecting appropriate co-occurrence criteria that corresponds to the purpose of the analysis. Additionally, we will perform similar experiments with several groups of customers that are segmented by each customer's average duration between orders. By this experiment, we attempt to discover the relationship between the optimal co-occurrence criteria and the customer's average duration between orders. Finally, by a series of experiments, we expect that we can provide basic guidelines for developing customized recommendation systems. Our experiments use a real dataset acquired from one of the largest internet shopping malls in Korea. We use 66,278 transactions of 3,847 customers conducted during the last two years. Overall results show that the accuracy of association rules of frequent shoppers (whose average duration between orders is relatively short) is higher than that of causal shoppers. In addition we discover that with frequent shoppers, the accuracy of association rules appears very high when the co-occurrence criteria of the training set corresponds to the validation set (i.e., target set). It implies that the co-occurrence criteria of frequent shoppers should be set according to the application purpose period. For example, an analyzer should use a day as a co-occurrence criterion if he/she wants to offer a coupon valid only for a day to potential customers who will use the coupon. On the contrary, an analyzer should use a month as a co-occurrence criterion if he/she wants to publish a coupon book that can be used for a month. In the case of causal shoppers, the accuracy of association rules appears to not be affected by the period of the application purposes. The accuracy of the causal shoppers' association rules becomes higher when the longer co-occurrence criterion has been adopted. It implies that an analyzer has to set the co-occurrence criterion for as long as possible, regardless of the application purpose period.

Bacterial Soft Rot of Celery by Erwinia carotovora subsp. carotovora (Erwinia carotovora subsp. carotovora에 의한 셀러리 세균성 무름병)

  • 박덕환;함영일;임춘근
    • Korean Journal Plant Pathology
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    • v.14 no.4
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    • pp.361-363
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    • 1998
  • Occurrence of soft rots was observed on celery that was massively grown in Pyungchang, Kangwon-Do, Korea. Soft rot symptom appeared first on the lower parts of the celery which eventually extended into whole aboveground parts of it. The casual organism isolated from the infected lesions was identified as Erwinia carotovora subsp. carotovora based on the physiological and chemical characteristics, and on the results of the Biolog program (Biolog Inc., U. S. A.). E. carotovora subsp. carotovora is the first described bacterium which causes the bacterial soft rot disease on celery in Korea.

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Discovery of Vespa binghami (Vespidae: Hymenoptera) in Korea

  • Kim, Jeong-Kyu;Kim, Il-Kwon
    • Animal Systematics, Evolution and Diversity
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    • v.27 no.1
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    • pp.105-107
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    • 2011
  • Vespa binghami Vecht, a poorly known vespine species, was discovered in Korea. This is the second treatment of this species on the Korean peninsula since the first report on Korean occurrence by Virula in 1925; however, the first one was based on practical Korean distributional information. Diagnostic description and digital images are provided.

First Record of o Freshwater Jellyfish, Craspedacusta sowerbii Lankester, 1880 (Limnomedusce, Olindiidae) from Reservoirs in Korea

  • Park, Jeong-Hui
    • Animal cells and systems
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    • v.2 no.3
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    • pp.303-308
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    • 1998
  • Freshwater jellyfishes were collected from Taechong Dam reservoir in Korea on September 1994. Tiny nontentacled hydroids were also collected from Taechong Dam and Chuam Dam reservoirs in Korea between September 1995 to September 1997. The medusae were identified into Craspedacusta sowerbii Lankester, 1880 and tiny hydroids were found to be in its polyp stages. It belongs to the family 0lindiidae in Limnomedusae and is first recorded from Korea. Environmental factors affecting the medusa occurrence are discussed.

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금융사고 실태 조사

  • Lee, Sang-Kyung
    • Journal of the Korea society of information convergence
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    • v.7 no.1
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    • pp.25-46
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    • 2014
  • After examining the current situations of financial frauds and the reasons for their occurrence in the financial institutions through examples of financial frauds in domestic and abroad, this study presents ways to prevent such financial scams. The preventive measures consist of activities before and after the occurrence of financial frauds and during normal financial operations. The activities are as follows: 1. Preventive activity should be strengthened before the occurrence of financial frauds. That is, first, the enforcement of consistent internal control is needed. Second, in order to block the probability of financial frauds involved with employees, ethics education and a reward program for inside tippers need to be run. Third, financial institutions need to apply for comprehensive insurance policy to minimize the lost in case. 2. Preventive activity should be strengthened during normal financial operations. First, self authentication system for customers needs to be introduced. Second, dealings of day, week, and month need to be thoroughly checked and the system of audit needs to be expanded. Third, message service for the information on financial frauds and their preventive measures needs to be expanded. Fourth, public notification system against examples of financial frauds needs to be expanded. 3. Preventive activity after the occurrence of financial frauds should be strengthened. First, awareness for preventive measures such as imposing penalty on the manager needs to be enhanced. Second, strict restrictions on financial frauders such as a criminal charge needs to be strengthened. Third, there should be legal devices and resolutions in order to retrieve all the money deceived by financial frauds.

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