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Validation of SwimCount™, a Novel Home-Based Device That Detects Progressively Motile Spermatozoa: Correlation with World Health Organization 5th Semen Analysis.
No full textPURPOSE:
We evaluated the usefulness of a home-based device (SwimCount™) compared with World Health Organization (WHO) 5th semen analysis in screening for male fertility in Asian men.
MATERIALS AND METHODS:
One hundred Asian men who visited CHA Seoul Station Fertility Center for evaluation of fertility were included. Semen samples were analyzed and compared with the SwimCount™ results. An aliquot of 0.5 mL of the semen sample was added to the SwimCount™ and a WHO 5th semen analysis was performed. Results were categorized as low (<5×10⁶/mL), and normal to high (≥5×10⁶/mL) total progressively motile sperm concentration. Receiver operating characteristic curve analysis was performed to evaluate the accuracy of the SwimCount™.
RESULTS:
The mean total progressively motile sperm concentration was 26.7×10⁶/mL. Semen analysis revealed that 28% of the samples were below the threshold count of 5 million/mL total progressively motile sperm concentration. The mean total progressively motile sperm concentration of the light color SwimCount™ result group determined by semen analysis was 7.5×10⁶/mL, and the mean total progressively motile sperm concentration of the moderate to dark color SwimCount™ result group was 34.2×10⁶/mL. An area under the receiver operating characteristic curve of 0.85 (95% confidence interval, 0.77-0.94; p<0.001) was obtained when the SwimCount™ was compared with semen analysis. The sensitivity and specificity were obtained at a cut off value of 5.0×10⁶/mL total progressively motile sperm concentration, giving a sensitivity and specificity of 87.5% and 73.4%.
CONCLUSIONS:
We confirmed the reliability of the SwimCount™ as a home-based device for male fertility by evaluating the total progressively motile sperm concentration
Experimental Demonstration on Quantum Sensitivity to Available Information in Decision Making
No full textWe present an experimental illustration on the quantum sensitivity of decision making machinery. In the decision making process, we consider the role of available information, say hint, whether it influences the optimal choices. To the end, we consider a machinery method of decision making in a probabilistic way. Our main result shows that in decision making process our quantum machine is more highly sensitive than its classical counterpart to the hints we categorize into "good" and "poor". This quantum feature originates from the quantum superposition involved in the decision making process. We also show that the quantum sensitivity persists before the quantum superposition is completely destroyed.The authors thank Jaewan Kim and Byoung Seung Ham for valuable discussions. J.B. thanks Marcin Wiesniak, Wieslaw Laskowski, Marcin Pawlowski. This research was supported through the National Research Foundation of Korea (NRF) grant (No. 2014R1A2A1A10050117 and No. 2016R1A2B4014370) and the Institute for Information and communications Technology Promotion (IITP-2018-2015-0-00385), funded by the Korea government(MSIT), Korea. This research was also implemented as a research project on quantum machine learning (No. 2018-104) by the ETRI affiliated research institute. J.B. acknowledge the support of the R&D Convergence program of NST (National Research Council of Science and Technology) of Republic of Korea (No. CAP-18-08-KRISS)
Self-healing phenomena using PVA coated granules for sustainable construction
No full textConcrete structures are susceptible to cracking which exacerbate the durability of these structures. For this purpose, self-healing phenomena has been introduced in the past few decades. In order to apply the granulated healing material (Granule) with PVA film coating in the concrete, cracks, which were generated by drying shrinkage, were introduced to plate-shaped concrete specimens incorporating Granule with PVA film coating. Subsequently, healing efficiency was verified by test about crack, which was subjected to the water supply. As a result, it is verified that the method by using water-soluble PVA film coating for maintaining self-healing efficiency of the granulated healing material will be the original approach for sustainable concrete with self-healing capability compared with the previous method.This research was supported by Basic Science ReSearch Program through a 2014 National Research Foundation of Korea(NRF) funded by the Ministry of Science, ICT and Future Planning (No. 2014R1A2A2A01007026)
Area Throughput Enhancement Using Next Generation Wi-Fi, IEEE 802.11ax
No full textIEEE 802.11, which focuses on wireless local area network (WLAN), has shown massive increase in demand in recent years. Research shows that wireless traffic will increase by more than 7 times from 2016 to 2021. IEEE 802.11ac, the most recent WLAN technology has a peak data rate of 433 Mbps per one 80 MHz spatial stream. However, the performance of individuals experiencing is very low due to interference from supersaturated APs and stations. To resolve this situation, the IEEE 802.11 task group is studying IEEE 802.11ax, which stands for High Efficiency Wireless (HEW) WLAN. In this paper, we describe the main features of IEEE 802.11ax
Start–End Time Detection in Baseball Videos for Automatic Pitching Trajectory Analysis
No full textA baseball pitching trajectory analysis system is used to train pitchers and provide baseball content for viewers. Previous systems needed a system manager because the trajectory was detected manually, thus system automation is essential for popularizing baseball pitching trajectory analysis systems, and detecting the pitching start and end times comprise the key point toward achieving this. In this paper, we define the pitching start and end times according to the situations in baseball games and accurately detect these points in time based on a physical model. Experiments on image data captured at a professional baseball game indicate that the proposed method could detect the start and end times of a pitch as accurately as a human can.This research project was supported by The Sports Promotion Fund of the Seoul Olympic Sports Promotion Foundation from the Ministry of Culture, Sports and Tourism
Effects of Information Insufficiency, Perceived Information Gathering Capacity, and Temporal Distance on People’s Information Seeking and Avoidance about Earthquake
No full text˂배경 및 목적˃ 본 연구는 위험정보 탐색처리 모형과 해석수준 이론을 적용하여 정보 불충분성, 정보 수집 능력 및 시간적거리가 지진에 관한 정보 추구 및 정보 회피에 미치는 주효과 및 상호작용 효과를 규명하고자 하였다. 또한이 효과가 지진 경험 유무에 따라 차이가 있는지 검토하였다.
˂방법˃ 전국에 거주하는 17세 이상의 성인 538명(개인 혹은 가족의 지진 경험자 309명 포함)을 대상으로 얻어진 온라인 설문 자료를 바탕으로 위계적 회귀분석을 실시했다.
˂결과˃ 첫째, 정보 불충분성과 정보 수집 능력은 정보 추구에 긍정적 영향을 미쳤으나, 정보 회피에는 유의미한 영향이 없었다. 둘째, 정보 불충분성은 지진 비경험 집단에서는 정보 추구에 긍정적 영향을, 정보 회피에는 부정적 영향을 미쳤으나, 지진 경험 집단에서는 통계적으로 유의미한 영향이 없었다. 셋째, 시간적 거리는 정보 추구에 부정적인 영향을, 정보 회피에는 긍정적인 영향을 미쳤다. 넷째, 시간적 거리가 가까울수록 정보수집 능력이 정보 추구 및 정보 회피에 미치는 영향이 컸다.
˂논의 및 결론˃ 본 연구는 지진 위험의 맥락에 위험정보 탐색처리 모형을 적용하고 해석수준 이론의 시간적 거리 개념을 이론적으로 통합했다는 이론적 함의와 지진 경험 여부 등 타겟에 따른 지진 위험의 커뮤니케이션 메시지 전략에 대한 실무적 함의를 제시하였다
A Colorimetric Multifunctional Sensing Method for Structural-Durability-Health Monitoring Systems
No full textA colorimetric multifunctional phototransmittance-based structural durability monitoring system is developed. The system consists of an array with four indium gallium zinc oxide (IGZO)-based phototransistors, a light source at a wavelength of 405 nm through a side-emitting optical fiber, and pH- and Cl-selective color-variable membranes. Under illumination at the wavelength of 405 nm at corrosion status, the pH- and Cl-responsive membrane, showing a change in their color, generates a change in the intensity of the transmitted light, which is received by the phototransistor array in the form of an electrical current. I-ds and R (I-ds/I-pH (12)) are inversely proportional to the pH, which ranges from 10 to 12. When the pH drops from 12 to 10, the magnitude of I-ds and R increases to approximate to 10(3). In the case of Cl detection, I-ds and R (I-ds/I-Cl (0 wt%)) increase nearly 50 times with an increase in Cl concentration of 0.05 wt%, and when the Cl concentration reaches 0.30 wt%, I-ds and R increase to approximate to 10(3) times greater. This multifunctional colorimetric durability sensing system demonstrates considerable potential as a novel smart-diagnostic tool of structural durability with high stability, high sensitivity, and multifunction.H.I. and S.H. contributed equally to this work. This research was supported in part by the National Research Foundation of Korea (2015R1A5A1037548 and 2018R1A2B2003558). This work was partly supported by the GRRC program of Gyeonggi province [GRRC Sungkyunkwan 2017‐B06, Nano‐biosensor based on flexible material]
Demand Response Management for Industrial Facilities: A Deep Reinforcement Learning Approach
No full textAs a major consumer of energy, the industrial sector must assume the responsibility for improving energy efficiency and reducing carbon emissions. However, most existing studies on industrial energy management are suffering from modeling complex industrial processes. To address this issue, a model-free demand response (DR) scheme for industrial facilities was developed. In practical terms, we first formulated the Markov decision process (MDP) for industrial DR, which presents the composition of the state, action, and reward function in detail. Then, we designed an actor-critic-based deep reinforcement learning algorithm to determine the optimal energy management policy, where both the actor (Policy) and the critic (Value function) are implemented by the deep neural network. We then confirmed the validity of our scheme by applying it to a real-world industry. Our algorithm identified an optimal energy consumption schedule, reducing energy costs without compromising production.Facilities: This work was supported in part by the National Research Foundation of Korea under the Framework of International Cooperation Program, South Korea - China, under Grant NRF-2016K2A9A2A11938310, and in part by the National Research Foundation of Korea under Grant NRF-2018K1A3A1A61026320
Determination of Urinary Caffeine Metabolites as Biomarkers for Drug Metabolic Enzyme Activities
No full textCaffeine is commonly taken via the daily dietary consumption of caffeine-containing foods. The absorbed caffeine is metabolized to yield various metabolites by drug-metabolizing enzymes, and measuring the levels of each caffeine metabolite can provide useful information for evaluating the phenotypes of those enzymes. In this study, the urinary concentrations of caffeine and its 13 metabolites were determined, and the phenotypes of drug metabolic enzymes were investigated based on the caffeine metabolite ratios. Human urine samples were pretreated using solid phase extraction, and caffeine and its metabolites were analyzed using liquid chromatography-tandem mass spectrometry. Based on the urinary caffeine metabolite concentrations, the caffeine metabolite ratios were calculated for six human subjects at specified time points after caffeine intake. Variations in urinary metabolite levels among individuals and time points were reported. In addition, the resultant enzyme activities showed different patterns, depending on the metabolite ratio equations applied. However, some data presented a constant metabolite ratio range, irrespective of time points, even at pre-dose. This suggests the possibility of urinary caffeine metabolite analysis for routine clinical examination. These findings show that urinary caffeine and the metabolite analysis would be useful in evaluating metabolic phenotypes for personalized medicine.This research was supported by the National Research Foundation of Korea funded by the Korean government (NRF-2017R1A2B4001814)
A Study on high efficiency Bridgeless PFC Converter applied SiC SBD
No full text본 논문은 Bridgeless PFC Converter의 환류 다이오드를 SiC SBD(Schottky Barrier Diode)로 제안하여 고효율화를 달성하였다. 또한 Bridgeless PFC Converter의 동작원리에 대한 설명을 통해 Bridgeless PFC Converter에서 환류 다이오드의 도통 구간을 나타내어 환류 다이오드의 손실에 따른 시스템 손실의 기여도를 검증하였고, SiC SBD 소자의 물성 및 역 회복 특성에 따른 장점을 설명하였으며 턴 온 손실과 턴 오프 손실을 측정하여 효율을 비교 분석하고, 소자 단품 특성을 확인하기 위한 다이오드의 역회복 파형 분석을 통하여 소자의 역회복 손실을 계산하였다. 소자 특성을 고려한 시뮬레이션 결과 값을 도출해내어 실제 시스템의 파형 분석 및 비교를 통해 그 결과 값을 검증하였다. 소자 특성을 고려하기 위하여 PSIM의 Thermal Module을 사용하여 시뮬레이션을 진행하였으며, 그 결과로 턴온 손실 0.6W, 턴 오프 손실 20.6W로 전체 스위칭 손실은 22.2W로 나타났다. 시작품 실험을 통하여 분석한 결과 턴온 손실 0.608W, 턴 오프 손실 21.62W로 전체 스위칭 손실 22.228W의 결과 값을 도출하였고, 두 결과 값의 비교로 실험 방법의 타당성을 입증하였다. 또한 최대 효율 94.58%의 고효율을 달성하였다.
This paper proposes a flyback diode of bridgeless PFC converter as SiC SBD (Schottky Barrier Diode) to achieve high efficiency. In addition, through the explanation of the operation principle of the bridgeless PFC converter, the conduction section of the freewheel diode is shown in the bridgeless PFC converter to verify the contribution of system loss due to the loss of the freewheel diode. The advantages of the SiC SBD device"s physical properties and the reverse recovery characteristics are explained, and the efficiency is measured by measuring the turn-on and turn-off losses. The loss was calculated. The simulation results were calculated in consideration of device characteristics and verified through the waveform analysis and comparison of the actual system. In order to consider the device characteristics, the simulation was conducted using the thermal module of PSIM. As a result of the prototype test, the turn-on loss was 0.608W and the turn-off loss was 21.62W, resulting in the total switching loss of 22.228W. The comparison of the two results proved the validity of the experimental method. In addition, a high efficiency of 94.58% is achieved