• 제목/요약/키워드: loss of self

검색결과 816건 처리시간 0.032초

질소로 희석된 프로판 동축류 층류 제트 부상화염에서 열손실에 의한 자기진동에 대한 동축류 속도 효과 (Effect of Coflow Air Velocity on Heat-loss-induced Self-excitation in Laminar Lifted Propane Coflow-Jet Flames Diluted with Nitrogen)

  • 이원준;윤성환;박정;권오붕;박종호;김태형
    • 한국연소학회지
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    • 제17권1호
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    • pp.48-57
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    • 2012
  • Laminar lifted propane coflow-jet flames diluted with nitrogen were experimentally investigated to determine heat-loss-related self-excitation regimes in the flame stability map and elucidate the individual flame characteristics. There exists a critical lift-off height over which flame-stabilizing effect becomes minor, thereby causing a normal heat-loss-induced self-excitation with O(0.01 Hz). Air-coflowing can suppress the normal heat-loss-induced self-excitation through increase of a Peclet number; meanwhile it can enhance the normal heat-lossinduced self-excitation through reducing fuel concentration gradient and thereby decreasing the reaction rate of trailing diffusion flame. Below the critical lift-off height. the effect of flame stabilization is superior, leading to a coflow-modulated heat-loss-induced self-excitation with O(0.001 Hz). Over the critical lift-off height, the effect of reducing fuel concentration gradient is pronounced, so that the normal heat-loss-induced self-excitation is restored. A newly found prompt self-excitation, observed prior to a heat-loss-induced flame blowout, is discussed. Heat-loss-related self-excitations, obtained laminar lifted propane coflow-jet flames diluted with nitrogen, were characterized by the functional dependency of Strouhal number on related parameters. The critical lift-off height was also reasonably characterized by Peclet number and fuel mole fraction.

Loss Minimization Control of Interior Permanent Magnet Synchronous Motors Considering Self-Saturation and Cross-Saturation

  • Pairo, Hamidreza;Khanzade, Mohammad;Shoulaie, Abbas
    • Journal of Power Electronics
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    • 제18권4호
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    • pp.1099-1110
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    • 2018
  • In this paper, a loss minimization control method for interior permanent magnet synchronous motors is presented with considering self-saturation and cross saturation. According to variation of the d-axis and q-axis inductances by different values of the d-axis and q-axis components of currents, it is necessary to consider self-saturation and cross saturation in the loss minimization control method. In addition, the iron loss resistance variation due to frequency variation is considered in the condition of loss minimization. Furthermore, the loss minimization control method is compared with maximum torque per ampere (MTPA), unity power factor (UPF) and $i_d=0$ control methods. Experimental results verify the performance and proper dynamic response of the loss minimization control method with considering self-saturation and cross saturation.

자기감시를 병행한 한의비만치료에서 체중감량 및 감량에 영향을 미치는 요인 분석: 후향적 관찰연구 (Korean Medicine with Self-monitoring for Weight Control and Factors Associated with Weight Loss: a Retrospective Observational Study)

  • 장인영;임주혁;박지선;김지성;김태훈
    • 대한한의학회지
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    • 제43권1호
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    • pp.87-98
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    • 2022
  • Objectives: The purpose of this study was to investigate the effect of weight loss in Korean Medicine (KM) obesity treatment combined with self-monitoring and to identify the relevant factors which are related to successful weight loss. In addition to this, adverse events reported by the patients were analyzed to assess the safety of KM treatments for obesity Methods: This was a retrospective observational study that analyzed the medical records of the patients that participated in the 10-week of KM treatment. All patients took herbal medicine for weight loss and were instructed to reduce calorie intake and adhere to self-monitoring. Clinical data including body weight were collected for evaluating the effect of the treatments. Behavior factors affecting weight loss were collected. The correlation between each factor and weight loss was analyzed. Adverse events (AEs) were collected at each time to evaluate the safety of the intervention. Results: One hundred eighteen patients' records were included in this study. The average weight loss was 7.64kg(74.59kg to 66.95kg). 94.9% of patients lost 5% or more of their initial weight. The degree of weight loss was identified to be related to self-assessment of diet control and self-assessment of appetite control. The average self-weighing frequency significantly increased(2.45 times/week before treatment and 4.70 times/weeks during treatment). Constipation, insomnia, and dizziness were found to be the most frequent AEs, and except for one case, most AEs were mild cases. Conclusion: From this study, we found that KM obesity treatment combined with self-monitoring showed significant weight loss without serious AE.

전력기기에서 $100 A/mm^2$급 Bi-2223테이프 ($100 A/mm^2$ Class Bi-2223 Tapes in Electromechanical Devices)

  • 류경우;최경주;성기철;류강식
    • 한국초전도ㆍ저온공학회논문지
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    • 제4권1호
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    • pp.55-60
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    • 2002
  • $100 A/mm^2$ class Bi-2223 tapes have recently become commercially available. Some important characteristics of the tapes, e .g. critical current, ac loss, characteristics at joint, fault current characteristics, are required for an application such as a power cable or a power transformer. In this paper they have been investigated experimentally. The results indicate that the self-field loss of the high current density tapes is not negligible, compared to resistive loss in a copper wire for the same currents. In a cable, the self-field loss for relatively large currents is much larger than the magnetization loss due to an external field. But in a transformer, the magnetization loss is dominant, compared to the self-field loss. Finally the fault current characteristics show that the high current density tapes are never safe from burn-out even for fault currents with a few cycles.

고온초전도체의 자기자계손실 측정 (Measurement of the Self-field Loss in the HTS Tape)

  • 심정욱;차귀수;이지광;한승엽
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1999년도 하계학술대회 논문집 A
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    • pp.274-276
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    • 1999
  • Transport current is the HTS tape generates the self field loss. To measure the self field loss, rectangular voltage tap has been used. In this paper, self field loss was measured using the spiral voltage tap method. Result of the measurement was compared with that of the theoretical.

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여대생의 신체만족도와 체중조절 (Body Satisfaction and Weight Loss in Women College Students)

  • 정승교;민소영
    • 기본간호학회지
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    • 제13권3호
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    • pp.485-492
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    • 2006
  • Purpose: The purpose of this study was to identify body satisfaction and weight loss experience according to individual's discrepancy between obesity by BMI (body mass index) and self-assessment. Method: The data were obtained by measuring height, weight and using a questionnaire to obtain data on self-assessment of obesity, body satisfaction and weight loss experience. The participants were 286 women college students in J city, Chungbuk. Results: The mean BMI of the women college student was $21.4{\pm}2.93kg/m^2$ which is within the normal range. The concordance rates between obesity by BMI and self-assessment were 54.1%, 39.9%, 61.5%, 78.6% (Kappa=.29) in underweight, normal, overweight, obese students respectively. Forty seven percent of students who were not obese (BMI $<23kg/m^2$) assessed themselves as obese. The mean body satisfaction of college students was very low and 64.3% of the students had a weight loss experience. The students who perceived themselves to be 'obese' even when their BMI was under $23kg/m^2$ reported lower body satisfaction and higher weight loss experience than other students. Conclusion: There were significant discrepancies between obesity by BMI and self-assessment in women college students. The self-assessment of obesity had a greater effect on body satisfaction and weight loss experience than actual BMI in women college students.

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대학생의 청소년기 상실경험에 대한 정서표현과 부정적 정서조절 방략이 우울에 미치는 영향: 자존감의 매개효과 (Effect of Emotional Expression and Maladaptive Emotion Regulation Strategies for Loss Experience in Adolescence among College Students in Depression : With Mediating Effect of Self-esteem)

  • 윤운영
    • 한국콘텐츠학회논문지
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    • 제19권4호
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    • pp.315-325
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    • 2019
  • 누구나 경험하는 상실경험은 보다 어린 시기에 경험되었을 경우에 더 부정적인 영향을 끼칠 수 있다. 본 연구는 대학생들의 청소년기 상실경험에 대한 정서표현과 부정적 정서조절방략이 우울에 미치는 영향에 대한 자존감의 매개효과를 살펴보았다. 연구에 참여한 총 380명의 대학생을 대상으로 지금까지 어떤 상실을 경험했는지, 상실 경험 후의 정서표현과 부정적 정서조절방략이 자존감의 정도에 따라 어떻게 우울에 영향을 끼치는 가를 알아보기 위해 SPSS 21.0과 Amos21.0 프로그램을 사용하여 분석하였다. 분석결과는 상실경험에 대한 정서표현은 우울에 부적인 관계를 보였고(${\beta}=-.180$, p<.01), 부정적 정서조절 방략은 우울과 정적인 관계(${\beta}=.266$, p<.001)를 보였다. 그리고 상실경험에 대한 정서표현은 자존감수준을 증가시킴으로 우울 수준을 감소시키며, 상실경험에 대한 부정적 정서조절방략은 자존감 수준을 저하시킴으로 우울 수준을 증가시키는 것으로 나타났다. 따라서 상실 이후 경험하게 되는 다양한 정서적 경험에 대해 누구에게라도 말하는 경험이 많을수록, 자신을 비난하지 않고 긍정적으로 생각하려고 할수록, 높은 자존감을 유지할수록 우울을 덜 경험할 수 있을 것이라고 예측해 볼 수 있다.

층류 동축류 제트 부상화염에서 부력에 의한 자기진동과 루이스 수에 의한 자기진동 비교에 관한 실험적 연구 (Experimental Study on Comparison between Buoyancy Driven and Lewis Number Induced Self-excitations in Laminar Lifted Coflow-jet Flames)

  • 이원준;박정;권오붕;윤진한;길상인
    • 한국연소학회지
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    • 제19권2호
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    • pp.21-27
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    • 2014
  • Experimental study in laminar propane coflow jet flames has been conducted to investigate self-excitations. For various propane mole fractions and jet velocities, two types of self-excitation were observed: (1) buoyancydriven self-excitation (hereafter called BDSE) and (2) Lewis-number-induced self-excitation coupled with (1) (hereafter called LCB). The mechanism of Lewis-number-induced self-excitation (hereafter called LISE) is proposed. When the system $Damk\ddot{o}hler$ number was lowered, LISE was shown to be launched. The LISE is closely related to heat loss, such that it can be launched in even helium-diluted methane coflow-jet flame (Lewis number less than unity). Particularly, The LISE becomes significant as the $Damk\ddot{o}hler$ number decreases and heat-loss is excessively large.

A Novel Self-Learning Filters for Automatic Modulation Classification Based on Deep Residual Shrinking Networks

  • Ming Li;Xiaolin Zhang;Rongchen Sun;Zengmao Chen;Chenghao Liu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권6호
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    • pp.1743-1758
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    • 2023
  • Automatic modulation classification is a critical algorithm for non-cooperative communication systems. This paper addresses the challenging problem of closed-set and open-set signal modulation classification in complex channels. We propose a novel approach that incorporates a self-learning filter and center-loss in Deep Residual Shrinking Networks (DRSN) for closed-set modulation classification, and the Opendistance method for open-set modulation classification. Our approach achieves better performance than existing methods in both closed-set and open-set recognition. In closed-set recognition, the self-learning filter and center-loss combination improves recognition performance, with a maximum accuracy of over 92.18%. In open-set recognition, the use of a self-learning filter and center-loss provide an effective feature vector for open-set recognition, and the Opendistance method outperforms SoftMax and OpenMax in F1 scores and mean average accuracy under high openness. Overall, our proposed approach demonstrates promising results for automatic modulation classification, providing better performance in non-cooperative communication systems.

Process Evaluation of a Mobile Weight Loss Intervention for Truck Drivers

  • Wipfli, Brad;Hanson, Ginger;Anger, Kent;Elliot, Diane L.;Bodner, Todd;Stevens, Victor;Olson, Ryan
    • Safety and Health at Work
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    • 제10권1호
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    • pp.95-102
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    • 2019
  • Background: In a cluster-randomized trial, the Safety and Health Involvement For Truck drivers intervention produced statistically significant and medically meaningful weight loss at 6 months (-3.31 kg between-group difference). The current manuscript evaluates the relative impact of intervention components on study outcomes among participants in the intervention condition who reported for a post-intervention health assessment (n = 134) to encourage the adoption of effective tactics and inform future replications, tailoring, and enhancements. Methods: The Safety and Health Involvement For Truck drivers intervention was implemented in a Web-based computer and smartphone-accessible format and included a group weight loss competition and body weight and behavioral self-monitoring with feedback, computer-based training, and motivational interviewing. Indices were calculated to reflect engagement patterns for these components, and generalized linear models quantified predictive relationships between participation in intervention components and outcomes. Results: Participants who completed the full program-defined dose of the intervention had significantly greater weight loss than those who did not. Behavioral self-monitoring, computer-based training, and health coaching were significant predictors of dietary changes, whereas behavioral and body weight self-monitoring was the only significant predictor of changes in physical activity. Behavioral and body weight self-monitoring was the strongest predictor of weight loss. Conclusion: Web-based self-monitoring of body weight and health behaviors was a particularly impactful tactic in our mobile health intervention. Findings advance the science of behavior change in mobile health intervention delivery and inform the development of health programs for dispersed populations.