• Title/Summary/Keyword: SWS

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Long-term simultaneous monitoring observations of SiO and H2O masers toward Mira variable WX Serpentis

  • Lim, Jang Ho;Kim, Jaeheon;Son, Seong Min;Suh, Kyung-Won;Cho, Se-Hyung;Yang, Haneul;Yoon, Dong-Hwan
    • The Bulletin of The Korean Astronomical Society
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    • v.46 no.2
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    • pp.49.1-49.1
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    • 2021
  • We carried out simultaneous monitoring observations of five maser lines, H2O (22 GHz), SiO 𝝊 =1, 2, J =1-0 (43.1, 42.8 GHz), and SiO 𝝊 =1, J=2-1, J =3-2 (86.2, 129.3 GHz), toward the Mira variable star WX Serpentis with the 21-m antennas of the Korean VLBI Network (KVN) in 2009-2021 (~12 years). Most spectra of the H2O maser are well separated into two parts of two blue- and one redshifted features within ± 10 km s-1 of the stellar velocity. All detected SiO masers are generally concentrated within ± 5 km s-1 of the stellar velocity, and sometimes appear split into two components. Overall, the profiles of SiO and H2O masers detected in WX Serpentis illustrate typical characteristics of the Mira variable. In addition, flux variations of both SiO and H2O masers are well correlated with the optical light curve of the central star, showing a phase lag of ~ 0.1 for SiO masers and ~ 0.2 for H2O maser. This phenomenon is considered to be the direct effect of propagating shock waves generated by the stellar pulsation, because SiO and H2O masers are sequentially distributed at different positions with respect to the central star. In addition, we analyzed long-term trends and characteristics of maser velocities, maser ratio, and the velocity extents (the full width at zero power; FWZP). We also investigated a spectral energy distribution (SED) ranging from 1.2 to 240 ㎛ obtained using several infrared data: 2MASS, WISE, IRAS, ISO, COBE DIBRE, RAFGL, and AKARI (IRC and FIS). From the IRAS LRS and ISO SWS spectra of this star, we identified 9.7 and 12 ㎛ silicate emission features consistent with the SE6 spectrum model, corresponding to the typical AGB phase.

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Jet Lag and Circadian Rhythms (비행시차와 일중리듬)

  • Kim, Leen
    • Sleep Medicine and Psychophysiology
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    • v.4 no.1
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    • pp.57-65
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    • 1997
  • As jet lag of modern travel continues to spread, there has been an exponential growth in popular explanations of jet lag and recommendations for curing it. Some of this attention are misdirected, and many of those suggested solutions are misinformed. The author reviewed the basic science of jet lag and its practical outcome. The jet lag symptoms stemed from several factors, including high-altitude flying, lag effect, and sleep loss before departure and on the aircraft, especially during night flight. Jet lag has three major components; including external de synchronization, internal desynchronization, and sleep loss. Although external de synchronization is the major culprit, it is not at all uncommon for travelers to experience difficulty falling asleep or remaining asleep because of gastrointestinal distress, uncooperative bladders, or nagging headaches. Such unwanted intrusions most likely to reflect the general influence of internal desynchronization. From the free-running subjects, the data has revealed that sleep tendency, sleepiness, the spontaneous duration of sleep, and REM sleep propensity, each varied markedly with the endogenous circadian phase of the temperature cycle, despite the facts that the average period of the sleep-wake cycle is different from that of the temperature cycle under these conditions. However, whereas the first ocurrence of slow wave sleep is usually associated with a fall in temperature, the amount of SWS is determined primarily by the length of prior wakefulness and not by circadian phase. Another factor to be considered for flight in either direction is the amount of prior sleep loss or time awake. An increase in sleep loss or time awake would be expected to reduce initial sleep latency and enhance the amount of SWS. By combining what we now know about the circadian characteristics of sleep and homeostatic process, many of the diverse findings about sleep after transmeridian flight can be explained. The severity of jet lag is directly related to two major variables that determine the reaction of the circadian system to any transmeridian flight, eg., the direction of flight, and the number of time zones crossed. Remaining factor is individual differences in resynchmization. After a long flight, the circadian timing system and homeostatic process can combine with each other to produce a considerable reduction in well-being. The author suggested that by being exposed to local zeit-gebers and by being awake sufficient to get sleep until the night, sleep improves rapidly with resynchronization following time zone change.

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Study on the Fatigue Crack Behavior by the Stress Intensity Factor and AE Parameters (응력확대계수와 음향방출 변수를 이용한 피로균열 거동 연구)

  • Yoon, Dong-Jin;Jeong, Jung-Chae;Park, Phi-Lip;Kim, Ki-Bok;Lee, Seung-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.20 no.5
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    • pp.412-423
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    • 2000
  • By using the relation between stress intensity factor and AE parameter, new approach method for assessing the crack length and detectability of crack was proposed. Laboratory experiment was carried out to identify AE characteristics of fatigue cracks for compact tension specimen. The relationship between a stress intensity factor and AE signals activity as well as conventional AE parameter analysis was discussed. As a result, the features of specific parameter such as the length of crack growth the AE energy, the AE peak amplitude, and the cumulative AE hits, showed the almost same trend in their increase as the number of fatigue cycle increased. From the comparisons of peak amplitude and AE energy with stress intensity factor, it was verified that the higher stress intensity factors generated AE signals with higher peak amplitude and a larger number of AE counts. If we can get more reliable database for the relation between AE parameters and stress intensity factor, this approach will provide a good information for evaluating both the existence of crack and the minimum detectable size of crack.

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A Study on the Standards of Medical-Nutritional-Education by the Type of Bariatric Surgery in Morbid-obesity Patients (고도비만 환자의 수술적 치료방법에 따른 영양교육 기준 설정에 관한 연구)

  • Kim, Hye-Jin;NamGung, Sin-A;Hong, Jeong-Im;Mok, Hee-Jung
    • Journal of the Korean Dietetic Association
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    • v.16 no.2
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    • pp.178-187
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    • 2010
  • This study examined the effects of postoperative medical nutrition therapy on patients who had undergone bariatric surgery. Eighty seven patients who underwent bariatic-surgery at Yeouido St. Mary's Hospital from January 2007 to April 2009 were evaluated. The bariatric surgery patients included 42 Laparoscopic Roux-en Y gastric bypass (LRYGB) and 45 Laparoscopic adjustable gastric banding (LAGB) patients. Weight loss was more significant after LRYGB than after LAGB after 9 months (p<0.05). The LRYGB group was more satisfied with the weight loss (LRYGB 4.4/5.0, LAGB 3.0/5.0 p<0.001). The mean albumin, hemoglobin and hematocrit levels were significantly lower in the LRYGB group than in the LAGB group at the time of discharge (p<0.05~0.001). The GOT/GPT was significantly higher in the LRYGB group at the time of the operation than the LAGB group (p<0.01). The LRYGB group showed significantly lower intakes of total energy, carbohydrates, protein and fat from 1 week after surgery than the LAGB group. Multiple regression showed that the weight change after LRYGB was significantly more associated with the intakes of total energy at 1 week after surgery (p<0.01), SWS (sweets and high-calorie beverages) at 1 and 6 months after surgery (p<0.001), and fat at 3 months after surgery (p<0.01). In addition, LAGB was significantly more associated with the intakes of protein and NLS (non-liquid sweets) at 1 week after surgery (p<0.001, p<0.01), carbohydrate at 1 months after surgery (p<0.01), total energy at 3 months after surgery (p<0.001), HCL (high-calorie liquids) at 6 months after surgery (p<0.05), and fat at 9 months after surgery (p<0.01). These results suggest that continuous-follow-up medical nutrition therapy is needed according to the types of bariatric surgery, particularly during the weight loss phase (the first 1 week to 12 months).

Physicochemical Properties and Sugar-Snap Cookie Making Potentialities of Soft Wheat Cultivars and Lines (Triticum aestivum L. em Thell.) (연질밀(Triticum aestivum L. em Thell.)의 이화학적 특성과 sugar-snap cookie의 제조적성)

  • Lee, Yong-Suk;Kim, Jong-Goon;Won, Joon-Hyung;Chang, Hak-Gil
    • Korean Journal of Food Science and Technology
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    • v.34 no.5
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    • pp.846-855
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    • 2002
  • Several soft white spring and winter wheat cultivars were evaluated by analyzing physicochemical properties such as Single Kernel Characterization System (SKCS), milling properties, Rapid Visco-Analyzer (RVA), mixograph pattern, and sugar-snap cookie-making potentialities. Results of SKCS revealed kernel hardness had a positive correlation coefficient with test weight $(r=0.497^{*})$ and near-infrared reflectance (NIR) hardness $(r=0.495^{*})$. SKCS kernel weight had a significantly high correlation of $r=0.942^{**}$ with SKCS kernel size. The test weight had significantly high correlations with straight-grade flour yield $(r=0.720^{**})$, break flour yield $(r=0.490^{*})$, flour ash content $(r=-0.781^{**})$, and milling score $(r=0.838^{**})$. The average RVA peak viscosity of the soft white winter wheat was higher (195.1 unit) than the soft white winter wheat varieties (135.7 unit). A correlation was found between RVA peak viscosity and swelling volume. Significant correlation coefficients were obtained among cookie properties, milling properties, protein content, and mixograph absorption. The cookie top grain score had a correlation coefficient of $r=0.447^{*}$ with swelling volume.

Analysis on Correlation between AE Parameters and Stress Intensity Factor using Principal Component Regression and Artificial Neural Network (주성분 회귀분석 및 인공신경망을 이용한 AE변수와 응력확대계수와의 상관관계 해석)

  • Kim, Ki-Bok;Yoon, Dong-Jin;Jeong, Jung-Chae;Park, Phi-Iip;Lee, Seung-Seok
    • Journal of the Korean Society for Nondestructive Testing
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    • v.21 no.1
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    • pp.80-90
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    • 2001
  • The aim of this study is to develop the methodology which enables to identify the mechanical properties of element such as stress intensity factor by using the AE parameters. Considering the multivariate and nonlinear properties of AE parameters such as ringdown count, rise time, energy, event duration and peak amplitude from fatigue cracks of machine element the principal component regression(PCR) and artificial neural network(ANN) models for the estimation of stress intensity factor were developed and validated. The AE parameters were found to be very significant to estimate the stress intensity factor. Since the statistical values including correlation coefficients, standard mr of calibration, standard error of prediction and bias were stable, the PCR and ANN models for stress intensity factor were very robust. The performance of ANN model for unknown data of stress intensity factor was better than that of PCR model.

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Comparative analysis of sensory profiles of commercial cider vinegars from Korea, China, Japan, and US by SPME/GC-MS, E-nose, and E-tongue (한국, 중국, 일본, 미국산 시판 사과식초의 관능적 품질 비교를 위한 SPME-GC/MS, 전자코 및 전자혀 분석)

  • Jo, Yunhee;Gu, Song-Yi;Chung, Namhyeok;Gao, Yaping;Kim, Ho-Jin;Jeong, Min-Hee;Jeong, Yong-Jin;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.48 no.5
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    • pp.430-436
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    • 2016
  • Solid phase microextraction and gas chromatography-mass spectrometry (SPME/GC-MS), electronic nose, and electronic tongue were used to characterize the sensory profiles of cider vinegars from Korea (K1-2), China (C1-2), Japan (J1-2), and US (U1-2). SPME-GC/MS detected acetic acid as the common volatile compound in all vinegars, in addition to isovaleric acid, octanoic acid, and phenethyl acetate. Acids and acetic esters were the major components of Korean and US vinegar samples, respectively. Chinese vinegars had high ethyl acetate content, while Japanese samples were characterized by a low content of acetic acid. Principal component analysis (PCA) pattern provided a clear categorical discrimination of Chinese vinegars by E-nose and E-tongue analyses. The instrumental sensory scores and the taste attributes for flavor ($r^2=0.9431$), sourness ($r^2=0.9515$), and sweetness ($r^2=0.8325$) were highly correlated. Therefore, SPME/GC-MS, E-nose, and E-tongue analyses may be useful tools to discriminate the sensory profiles of cider vinegars of different origins.

Discrimination of geographical origins of raw ginseng using the electronic tongue (전자혀를 이용한 수삼의 원산지 판별)

  • Dong, Hyemin;Moon, Ji Young;Lee, Seong Hun
    • Korean Journal of Food Science and Technology
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    • v.49 no.4
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    • pp.349-354
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    • 2017
  • The geographical origins of raw ginseng (RG) were discriminated using an electronic tongue. Taste screening, DFA (discriminant function analysis), and CDA (canonical discriminant analysis) were used to statistically analyze the data. The taste profile patterns of umami, bitterness, and sweetness of the Korean RG was different from those of the Chinese RG. The Korean RG was stronger than the Chinese RG regarding the taste of umami. DFA discriminated the geographical origins of 154 samples, with a few overlapping samples, between the Korean and Chinese RG. CDA showed that the accuracy of origin discrimination for the Korean and Chinese RGs were 87.01 and 94.81%, respectively. The final accuracy of origin discrimination was 90.91%. The distance between the centroids of each group was 2.7463. Thus, the electronic tongue analysis can be used to efficiently differentiate the geographical origins of RG.

Effects of a Logotherapy-Based Music and Imagery Program on the Self-Worth of Personal Assistants for the Disabled (의미치료에 기반한 음악과 심상 프로그램이 장애인 활동보조인의 자기가치감에 미치는 효과)

  • Hong, Geum Na;Kim, Seong Chan;Choi, Min Joo
    • Journal of Naturopathy
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    • v.10 no.1
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    • pp.1-9
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    • 2021
  • Purpose: This study has proved the intervention effects of the proposed logotherapy-based music imagery (LBMI) program on the self-worth of the personal assistants for the disabled. The program, in the image activities and at the stage of postlude after listening to music, unites logodrama of logotherapy, paradoxical intention and dereflected techniques. The intervention effects of the LBMI program were tested for the 28 personal assistants for the disabled who found themselves without the value and meaning of life and were randomly equally divided into the experimental and control groups. This intervention was carried out for the six different terms, each of which was alloted 60 minutes. To evaluate the intervention effects, the self-worth scale were examined before and after the intervention for both experimental and control group. The result shows that the self-worth improved significantly in the experimental group(p < 0.001), whereas it remained unchanged in the control group(p > 0.459). This finding proves that the proposed LBMI program ameliorates the self-worth of the personal assistants for the disabled.