• Title/Summary/Keyword: NB

Search Result 3,585, Processing Time 0.03 seconds

Reproductive Cycle of the Echiuroid Worm Urechis unicinctus(von Drasche) in Southern Korea (한국산 개불, Urechis unicinctus (von Drasche)의 생식주기)

  • 최상덕;김호진;이원교;곽은주;윤호섭;라성주;이인곤
    • Journal of Aquaculture
    • /
    • v.13 no.2
    • /
    • pp.169-174
    • /
    • 2000
  • Reproductive cycle of U. unicinctus was studied from September 1998 to August 1999, using gonadosomatic index (CSI) as an indicator. In November, the CSI values were maximum for male (6.2) and female (7.0), respectively; the values were lowest for them (1.0 and 0.5) during the successive february. Subsequently, they rapidly increased and attained peak by March-April. The values decreased again in both sexes and remained unchanged until August. The index increased in October to attain the peak by November. The CSI values clearly indicated that there are two spawning events in a year, namely the first one during April-May and the second one in December. Reproductive cycle was classified into the following successive stages: in female, multipication (January~February, June ~Setember), maturation (March~April, November), spent (May and December), degeneration and resting (June and January), and in male, multiplication January ~ february, June ~September), maturation (March~April, October~November), spent (May and December) and degeneration and resting (January and June). Histological observations revealed that oocytes in the ovary matured simultaneously in November and March. At the same time, the envelopes of matured testis became thinner than those in the early stage.

  • PDF

Effect of the Particle Size and Unburned Carbon Content on the Separation Efficiency of Fly ash in the Countercurrent Column Flotation (向流컬럼浮選機에서 石炭灰의 크기 및 未燃炭素 含量이 分離特性에 미치는 영향)

  • 이정은;이재근
    • Resources Recycling
    • /
    • v.9 no.6
    • /
    • pp.36-44
    • /
    • 2000
  • Fly ash was composed of the unburned carbon and mineral particles. The former was able to attach on the bubbles, while the latter was not. Therefore, it was possible to separate the unburned carbon and the mineral from fly ash using the froth flotation process. This study was carried out to evaluate the separation efficiency as a function of the ny ash particle properties in the column flotation. Separation efficiency was analyzed for various size fraction of -38 fm,38~125 fm and 1125 W, and for various fly ash samples containing 7, 11, and 20 wt% unburned carbon. For the size fractions of -38 fm containing 7 wt% unburned carbon, separation efficiency was 86ft, whereas separation efficiency was found to be 74% for the size fraction of +125$\mu\textrm{m}$ containing 20 wt% unburned carbon. The results indicated that separation efficiency increased with the decrease in the particle size and the unburned carbon content of the fly ash.

  • PDF

Evaluation of the Congenital Hypothyroidism for Newborn Screening Program in Korea: A 14-year Retrospective Cohort Study (한국인 선천성 갑상선기능저하증에 대한 신생아선별검사의 14년간의 후향적 연구; 발생빈도와 유효성)

  • Yoon, Hye-Ran;Ahn, Sunhyun;Lee, Hyangja
    • Journal of The Korean Society of Inherited Metabolic disease
    • /
    • v.19 no.1
    • /
    • pp.1-11
    • /
    • 2019
  • Purpose: Congenital hypothyroidism (CH) is the most common congenital endocrine disorder. The purpose of the present study was to determine the incidence of CH in South Korea during the period from January 1991 to March 2004. Methods: Central data from each city branch of SCL (Seoul Clinical Reference Laboratories) in Yongin, South Korea, was gathered and collectively analyzed. Newborn screening (NBS) for CH was based on measuring the levels of neonatal thyroid stimulating hormone (TSH) and free T4 (a cut-off of 20 mIU/L and less than 0.8 ng/dL, respectively). Results: During the study period, 671,805 live births were screened for CH based on TSH and free T4 ELISA assays. A total of 159 newborns were deemed positive for CH out of 671,805, with a corresponding incidence of 1 in 4,225. When a cut-off of 20 mIU/L was used in TSH assays, the associated sensitivity, specificity, and positive predictive values (PPV) were 100.0%, 99.7%, and 10.8%, respectively. When a cut-off of 0.8 ng/dL in free T4 assays was used, the associated sensitivity, specificity, and PPV were 100.0%, 98.5%, and 3.9%, respectively. Conclusion: CH incidence in South Korea as evidenced by the results of NBS was compared with its incidence and comparable to the other countries prior to 2004.

  • PDF

Detection of Salmonella spp. in Seafood via Desalinized DNA Extraction Method and Pre-culture (전배양과 탈염과정을 포함하는 DNA 추출법을 이용한 분자생물학적 방법으로 수산물 중 오염된 Salmonella spp.의 검출)

  • Ye-Jun Song;Kyung-Jin Cho;Eun-Ik Son;Du-Min Jo;Young-Mog Kim;Seul-Ki Park
    • Journal of Food Hygiene and Safety
    • /
    • v.38 no.3
    • /
    • pp.123-130
    • /
    • 2023
  • Salmonella spp. are prevalent foodborne pathogens that are infective at relatively low concentrations, thus posing a serious health threat, especially to young children and the elderly. In several countries, the management and regulation of Salmonella spp. in food, including seafood, adhere to a negative detection standard. The risk of infection is particularly high when seafood is consumed raw, which underscores the importance of timely detection of pathogenic microorganisms, such as Salmonella. Accordingly, this study aimed to develop a combined pre-treatment and detection method that includes pre-culture and DNA extraction in order to detect five species of Salmonella at concentrations below 10 CFU/mL in seafood. The effectiveness of the proposed method was assessed in terms of the composition of the enrichment (pre-culture) medium, minimum incubation time, and minimum cell concentration for pathogen detection. Furthermore, a practical DNA extraction method capable of effectively handling high salt conditions was tested and found to be successful. Through polymerase chain reaction, Salmonella spp. Were detected and positively identified in shellfish samples at cell concentrations below 10 CFU/g. Thus, the proposed method, combining sample pre-treatment and cell culture with DNA extraction, was shown to be an effective strategy for detecting low cellular concentrations of harmful bacteria. The proposed methodology is suitable as an economical and practical in situ pre-treatment for effective detection of Salmonella spp. in seafood.

Sentiment Analysis of Movie Review Using Integrated CNN-LSTM Mode (CNN-LSTM 조합모델을 이용한 영화리뷰 감성분석)

  • Park, Ho-yeon;Kim, Kyoung-jae
    • Journal of Intelligence and Information Systems
    • /
    • v.25 no.4
    • /
    • pp.141-154
    • /
    • 2019
  • Rapid growth of internet technology and social media is progressing. Data mining technology has evolved to enable unstructured document representations in a variety of applications. Sentiment analysis is an important technology that can distinguish poor or high-quality content through text data of products, and it has proliferated during text mining. Sentiment analysis mainly analyzes people's opinions in text data by assigning predefined data categories as positive and negative. This has been studied in various directions in terms of accuracy from simple rule-based to dictionary-based approaches using predefined labels. In fact, sentiment analysis is one of the most active researches in natural language processing and is widely studied in text mining. When real online reviews aren't available for others, it's not only easy to openly collect information, but it also affects your business. In marketing, real-world information from customers is gathered on websites, not surveys. Depending on whether the website's posts are positive or negative, the customer response is reflected in the sales and tries to identify the information. However, many reviews on a website are not always good, and difficult to identify. The earlier studies in this research area used the reviews data of the Amazon.com shopping mal, but the research data used in the recent studies uses the data for stock market trends, blogs, news articles, weather forecasts, IMDB, and facebook etc. However, the lack of accuracy is recognized because sentiment calculations are changed according to the subject, paragraph, sentiment lexicon direction, and sentence strength. This study aims to classify the polarity analysis of sentiment analysis into positive and negative categories and increase the prediction accuracy of the polarity analysis using the pretrained IMDB review data set. First, the text classification algorithm related to sentiment analysis adopts the popular machine learning algorithms such as NB (naive bayes), SVM (support vector machines), XGboost, RF (random forests), and Gradient Boost as comparative models. Second, deep learning has demonstrated discriminative features that can extract complex features of data. Representative algorithms are CNN (convolution neural networks), RNN (recurrent neural networks), LSTM (long-short term memory). CNN can be used similarly to BoW when processing a sentence in vector format, but does not consider sequential data attributes. RNN can handle well in order because it takes into account the time information of the data, but there is a long-term dependency on memory. To solve the problem of long-term dependence, LSTM is used. For the comparison, CNN and LSTM were chosen as simple deep learning models. In addition to classical machine learning algorithms, CNN, LSTM, and the integrated models were analyzed. Although there are many parameters for the algorithms, we examined the relationship between numerical value and precision to find the optimal combination. And, we tried to figure out how the models work well for sentiment analysis and how these models work. This study proposes integrated CNN and LSTM algorithms to extract the positive and negative features of text analysis. The reasons for mixing these two algorithms are as follows. CNN can extract features for the classification automatically by applying convolution layer and massively parallel processing. LSTM is not capable of highly parallel processing. Like faucets, the LSTM has input, output, and forget gates that can be moved and controlled at a desired time. These gates have the advantage of placing memory blocks on hidden nodes. The memory block of the LSTM may not store all the data, but it can solve the CNN's long-term dependency problem. Furthermore, when LSTM is used in CNN's pooling layer, it has an end-to-end structure, so that spatial and temporal features can be designed simultaneously. In combination with CNN-LSTM, 90.33% accuracy was measured. This is slower than CNN, but faster than LSTM. The presented model was more accurate than other models. In addition, each word embedding layer can be improved when training the kernel step by step. CNN-LSTM can improve the weakness of each model, and there is an advantage of improving the learning by layer using the end-to-end structure of LSTM. Based on these reasons, this study tries to enhance the classification accuracy of movie reviews using the integrated CNN-LSTM model.