• 응용통계연구
• /
• 제28권2호
• /
• pp.241-250
• /
• 2015

경시적 자료 연구의 중요한 주제 중의 하나는 시간이 지남에 따라 개인의 건강 상태가 어떻게 변하는지를 추적하는 확률이다. 질병의 상태를 시간의 흐름에 따라 추적하는 것은 장기간에 걸친 임상적 관찰 연구의 계획과 분석, 그리고 질병의 예방과 치료에 중요한 의미를 지닌다. 본 논문에서는 두 다른 시점에서 각 개인의 건강 상태에 대한 조건부 확률을 추정해내는 순위 추적 확률에 대하여 연구하였다. 순위 추적 확률과 순위 추적 확률비를 추정하기 위하여 선형 혼합 효과 모형을 고려하였다. 본 논문의 방법은 아동을 대상으로 심혈관계 질환의 위험요인을 연구하는 역학 자료에 적용되었다.

• 대한한방소아과학회지
• /
• 제33권3호
• /
• pp.103-111
• /
• 2019

Objectives The purpose of this study is to understand the correlations between lung, large intestine, and skin of 3-week-old mice in which ulcerative colitis was induced, up on administration of Coptidis rhizome and Glycyrrhiza uralensis mixed extract. Methods Mice were divided into 4 groups as follows; no treatment group (Ctrl group), ulcerative colitis-induced mice group (UE group), ulcerative colitis-induced mice group after administering Pentasa (PT group), ulcerative colitis-induced mice group after administering Coptidis rhizoma and Glycyrrhiza uralensis mixed extract (CGT group). Mice were induced ulcerative colitis by Dextran sulfate sodium (DSS). After 5 days of administration, We obvserved anti-inflammatory effect, alveolar formation, and skin barrier control in the colon mucosa. Results The CGT group was observed arrangement of normal intestinal cells, Infiltration of less inflammatory cells. The CGT significantly decreased positive rseponse of $TNF-{\alpha}$, p-IkB, Caspase 3 in large intestine, and significantly increased positive rseponse of EGF, IGF, catalase, Filaggrin, involucrin, loricrin. Conclusions The results of this study show the correlation of Lung-Large intestine-Skin by administering Coptidis rhizoma and Glycyrrhiza uralensis mixed extract to ulcerative colitis-induced mice.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제14권12호
• /
• pp.4664-4681
• /
• 2020

Modulation recognition (MR) plays a key role in cognitive radar, cognitive radio, and some other civilian and military fields. While existing methods can identify the signal modulation type by extracting the signal characteristics, the quality of feature extraction has a serious impact on the recognition results. In this paper, an end-to-end MR method based on long short-term memory (LSTM) and the gated recurrent unit (GRU) is put forward, which can directly predict the modulation type from a sampled signal. Additionally, the sliding window method is applied to fast-changing mixed-modulation signals for which the signal modulation type changes over time. The recognition accuracy on training datasets in different SNR ranges and the proportion of each modulation method in misclassified samples are analyzed, and it is found to be reasonable to select the evenly-distributed and full range of SNR data as the training data. With the improvement of the SNR, the recognition accuracy increases rapidly. When the length of the training dataset increases, the neural network recognition effect is better. The loss function value of the neural network decreases with the increase of the training dataset length, and then tends to be stable. Moreover, when the fast-changing period is less than 20ms, the error rate is as high as 50%. As the fast-changing period is increased to 30ms, the error rates of the GRU and LSTM neural networks are less than 5%.

• 한국치위생학회지
• /
• 제21권2호
• /
• pp.119-128
• /
• 2021

Objectives: The aim of this study was to investigate the effect of breastfeeding on the occurrence of early childhood caries in Korean infants and toddlers. Methods: Data on oral examinations of infants and toddlers of the National Health Insurance Service were analyzed. The study subjects were children who participated in both the first, second, and third oral examinations and the first general health examination in 2008-2017 (n=142,185). Based on the responses to the questionnaire, the subjects were classified into breastfeeding, formula feeding, and mixed feeding groups. The participants were monitored for the development of early childhood caries in three sequential oral examinations. Results: Based on the oral examination results conducted at 54-65 months old, the decayed-filled teeth index of the breastfeeding group was the highest (2.03±3.08), followed by the mixed (1.96±3.03) and the formula feeding groups (1.82±2.91). The Cox proportional hazard regression model including all the variables showed that the risk of developing dental caries was significantly lower in the formula (hazard ratio [HR], 0.85) and mixed feeding groups (HR, 0.91) than in the breastfeeding group. Conclusions: Breastfeeding children have a higher risk of early childhood caries; therefore, oral hygiene education and regular dental check-ups are necessary.

• 농촌지도와개발
• /
• 제30권4호
• /
• pp.171-186
• /
• 2023

This study aims to explore comprehensively the effects of a flower craft activity program focused on perceived stress, depression, and self-esteem of adult with mixed methods. The main results of this study are as follows. In the mixed analysis results, perceived stress was reduced by immersing oneself in completing one's own work through flower craft activities, as distracting thoughts in the head disappeared. In the case of depression, depression decreased in the relationship between group members who worked together to complete their own work through flower craft activities. In the case of self-esteem, it was analyzed that flower craft activities had the effect of increasing self-esteem through the satisfaction of the need for life and self-esteem. In future study, this suggests that the healing program applied based on this can be comprehensively reviewed, modified, and supplemented to reorganize it into a more effective flower craft activity program.

• 센서학회지
• /
• 제33권3호
• /
• pp.165-172
• /
• 2024

In this study, we investigated the detection properties of piezoresistive carbon nanotubes/polydimethylsiloxane (CNT/PDMS) devices with porous structures under applied pressure. The device, having dimensions of 10 mm × 10 mm × 5 mm, was fabricated with a porosity of 74.5%. To fabricate piezoresistive CNT/PDMS devices, CNTs were added using two different methods. In the first method, the CNTs were mixed with PDMS before the fabrication of the porous structure, while in the second, the CNTs were coated after the fabrication of the porous structure. Various detection properties of the fabricated devices were examined at different applied pressures. The CNT-coated device exhibited stable outputs with lesser variation than the CNT-mixed device. Moreover, the CNT-coated device exhibited improved reaction properties. The response time of the CNT-coated device was 1 min, which was approximately about 20 times faster than that of the CNT-mixed device. Considering these properties, CNT-coated devices are more suitable for sensing devices. To verify the CNT-coated device as a real sensor, it was applied to the gripping sensor system. A multichannel sensor system was used to measure the pressure distribution of the gripping sensor system. Under various gripping conditions, this system successfully measured the distributed pressures and exhibited stable dynamic responses.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
• /
• pp.462-466
• /
• 1989

This paper describes the methods of spline low-order polynomial trajectory planning using only a few limited look-ahead knots on the desired trajectory for the real-time computing. Specifically presented are the mixed joint trajectory planning methods which apply linear or LSPB method to initial and finial segments, overlapped cubic spline method to the other segments, where the displacements for initial and finial segments are chosen to be relatively smaller than the displacements for the other, equidistant segments. Experimental and simulation results of these methods show smooth motions and improved path tracking performances compared with any other interpolated joint trajectory planning methods.

• Communications for Statistical Applications and Methods
• /
• 제26권5호
• /
• pp.507-517
• /
• 2019

Statistical matching is a method of combining multiple sources of data that are extracted or surveyed from the same population. It can be used in situation when variables of interest are not jointly observed. It is a low-cost way to expect high-effects in terms of being able to create synthetic data using existing sources. In this paper, we propose the several statistical micro matching methods using a multinomial logistic regression model when all variables of interest are categorical or categorized ones, which is common in sample survey. Under conditional independence assumption (CIA), a mixed statistical matching method, which is useful when auxiliary information is not available, is proposed. We also propose a statistical matching method with auxiliary information that reduces the bias of the conventional matching methods suggested under CIA. Through a simulation study, proposed micro matching methods and conventional ones are compared. Simulation study shows that suggested matching methods outperform the existing ones especially when CIA does not hold.

• 대한약침학회지
• /
• 제18권1호
• /
• pp.44-55
• /
• 2015

Objectives: Scolopendra subspinipes mutilans (S. subspinipes mutilans) is known as a traditional medicine and includes various amino acids, peptides and proteins. The amino acids in the pharmacopuncture extracted from S. subspinipes mutilans by using derivatization methods were analyzed quantitatively and qualitatively by using high performance liquid chromatography (HPLC) over a 12 month period to confirm its stability. Methods: Amino acids of pharmacopuncture extracted from S. subspinipes mutilans were derived by using O-phthaldialdehyde (OPA) & 9-fluorenyl methoxy carbonyl chloride (FMOC) reagent and were analyzed using HPLC. The amino acids were detected by using a diode array detector (DAD) and a fluorescence detector (FLD) to compare a mixed amino acid standard (STD) to the pharmacopuncture from centipedes. The stability tests on the pharmacopuncture from centipedes were done using HPLC for three conditions: a room temperature test chamber, an acceleration test chamber, and a cold test chamber. Results: The pharmacopuncture from centipedes was prepared by using the method of the Korean Pharmacopuncture Institute (KPI) and through quantitative analyses was shown to contain 9 amino acids of the 16 amino acids in the mixed amino acid STD. The amounts of the amino acids in the pharmacopuncture from centipedes were 34.37 ppm of aspartate, 123.72 ppm of arginine, 170.63 ppm of alanine, 59.55 ppm of leucine and 57 ppm of lysine. The relative standard deviation (RSD %) results for the pharmacopuncture from centipedes had a maximum value of 14.95% and minimum value of 1.795% on the room temperature test chamber, the acceleration test chamber and the cold test chamber stability tests. Conclusion: Stability tests on and quantitative and qualitative analyses of the amino acids in the pharmacopuncture extracted from centipedes by using derivatization methods were performed by using HPLC. Through research, we hope to determine the relationship between time and the concentrations of the amino acids in the pharmacopuncture extracted from centipedes.

• International Journal of Computer Science & Network Security
• /
• 제22권1호
• /
• pp.305-311
• /
• 2022

This research aimed to provide a profound description of the practices of social media users in the Kingdom of Saudi Arabia (KSA), specifically the users of Facebook^® (FB) and Snapchat^® (SC), the reasons for these practices, decisions made, and the people involved. Such research would be of significant help to designers and policymakers of social media applications in understanding user practices when using social media applications and the reasons for such practices in the KSA. This better comprehension would be of significant help in improving current applications and creating new ones. According to the data analysis, there was a clear preference for SC over FB in the KSA. Most participants with SC accounts were described as very active users, accessing their accounts at least once a day compared to FB users. The users were led by this high preference for SC to create new words derived from the name of the application and use them in daily life. We showed our experience of carrying out a study in which the main objective was to collect factual empirical data from participants about their daily usage of social media applications while considering the unique cultural settings in the KSA. Mixed quantitative and qualitative methods were used to triangulate the data, increasing its trustworthiness and validity. Multiple perspectives were obtained using various data collection methods. Therefore, conclusions would not be confounded with limitations of any particular methodology or with conditions of any collection rounds. This research would constitute a valuable guide for researchers intending to use methods with male and female informants from different cultures, preparing them for potential challenges and suggesting possible solutions.