• Title/Summary/Keyword: Fluctuation effect

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A Study on the Application of Low Crest Structures to Reduce Wave Overtopping (월파저감을 위한 저마루 구조물의 적용성 검토)

  • Kyu-Tae, Shim;Kyu-Han, Kim;Ki-Seock, Cha
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.34 no.6
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    • pp.290-302
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    • 2022
  • In this study, it was examined for the reduction of wave overtopping and water level fluctuation in front of the revetment when applying a reinforcement method to revetment where wave overtopping occurs. As a result of the study, in the case of the cross-sectional experiment. more than 70% of the wave overtopping reduction effect depending on the reinforcement conditions was occurred, and it was analyzed that the result increases by about four times or more in the comparison with the 3d test. The average water level in front of the revetment was lowered when a low crest structure was not installed. and there was a tendency to rise under the condition of low crest structures installed. In the comparison with the wave basin test, there was a difference of about 0.5 to 0.6 times when a low crest structure was not installed, and it was increased by 5.5 times after low crest structures were installed.

Effect of fermented red ginseng on gut microbiota dysbiosis- or immobilization stress-induced anxiety, depression, and colitis in mice

  • Yoon-Jung Shin;Dong-Yun Lee;Joo Yun Kim;Keon Heo;Jae-Jung Shim;Jung-Lyoul Lee;Dong-Hyun Kim
    • Journal of Ginseng Research
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    • v.47 no.2
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    • pp.255-264
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    • 2023
  • Background: Red ginseng (RG) alleviates psychiatric disorders. Fermented red ginseng (fRG) alleviates stress-induced gut inflammation. Gut dysbiosis causes psychiatric disorders with gut inflammation. To understand the gut microbiota-mediated action mechanism of RG and fRG against anxiety/depression (AD), we investigated the effects of RG, fRG, ginsenoside Rd, and 20(S)-β-D-glucopyranosyl protopanaxadiol (CK) on gut microbiota dysbiosis-induced AD and colitis in mice. Methods: Mice with AD and colitis were prepared by exposing to immobilization stress (IS) or transplanting the feces of patients with ulcerative colitis and depression (UCDF). AD-like behaviors were measured in the elevated plus maze, light/dark transition, forced swimming, and tail suspension tests. Results: Oral gavage of UCDF increased AD-like behaviors and induced neuroinflammation, gastrointestinal inflammation, and gut microbiota fluctuation in mice. Oral administration of fRG or RG treatment reduced UCDF-induced AD-like behaviors, hippocampal and hypothalamic IL-6 expression, and blood corticosterone level, whereas UCDF-suppressed hippocampal BDNF+NeuN+ cell population and dopamine and hypothalamic serotonin levels increased. Furthermore, their treatments suppressed UCDF-induced colonic inflammation and partially restored UCDF-induced gut microbiota fluctuation. Oral administration of fRG, RG, Rd, or CK also decreased IS-induced AD-like behaviors, blood IL-6 and corticosterone and colonic IL-6 and TNF-α levels, and gut dysbiosis, while IS-suppressed hypothalamic dopamine and serotonin levels increased. Conclusion: Oral gavage of UCDF caused AD, neuroinflammation, and gastrointestinal inflammation in mice. fRG mitigated AD and colitis in UCDF-exposed mice by the regulation of the microbiota-gut-brain axis and IS-exposed mice by the regulation of the hypothalamic-pituitary-adrenal axis.

Plant co-occurrence patterns and soil environments associated with three dominant plants in the Arctic

  • Deokjoo Son
    • Journal of Ecology and Environment
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    • v.47 no.1
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    • pp.1-13
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    • 2023
  • Background: The positive effects of Arctic plants on the soil environment and plant-species co-occurrence patterns are known to be particularly important in physically harsh environments. Although three dominant plants (Cassiope tetragona, Dryas octopetala, and Silene acaulis) are abundant in the Arctic ecosystem at Ny-Ålesund, Svalbard, few studies have examined their occurrence patterns with other species and their buffering effect on soil-temperature and soil-moisture fluctuation. To quantify the plant-species co-occurrence patterns and their positive effects on soil environments, I surveyed the vegetation cover, analyzed the soil-chemical properties (total carbon, total nitrogen, pH, and soil organic matter) from 101 open plots, and measured the daily soil-temperature and soil-moisture content under three dominant plant patches and bare soil. Results: The Cassiope tetragona and Dryas octopetala communities increased the soil-temperature stability; however, the three dominant plant communities did not significantly affect the soil-moisture stability. Non-metric multidimensional scaling separated the sampling sites into three groups based on the different vegetation compositions. The three dominant plants occurred randomly with other species; however, the vegetation composition of two positive co-occurring species pairs (Oxyria digyna-Cerastium acrticum and Luzula confusa-Salix polaris) was examined. The plant species richness did not significantly differ in the three plant communities. Conclusions: The three plant communities showed distinctive vegetation compositions; however, the three dominant plants were randomly and widely distributed throughout the study sites. Although the facilitative effects of the three Arctic plants on increases in the soil-moisture fluctuation and richness were not quantified, this research enables a deeper understanding of plant co-occurrence patterns in Arctic ecosystems and thereby contributes to predicting the shift in vegetation composition and coexistence in response to climate warming. This research highlights the need to better understand plant-plant interactions within tundra communities.

Are Business Cycles in the Fashion Industry Affected by the News? -An ARIMAX Time Series Correlation Analysis between the KOSPI Index for Textile & Wearing Apparel and Media Agendas- (패션산업의 경기변동은 뉴스의 영향을 받는가? -섬유의복 KOSPI와 미디어 의제의 ARIMAX 시계열 상관관계 분석-)

  • Hyojung Kim;Minjung Park
    • Journal of the Korean Society of Clothing and Textiles
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    • v.47 no.5
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    • pp.779-803
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    • 2023
  • The growth of digital news media and the stock price index has resulted in economic fluctuations in the fashion industry. This study examines the impact of fashion industry news and macroeconomic changes on the Textile & Wearing Apparel KOSPI over the past five years. An auto-regressive integrated moving average exogenous time series model was conducted using the fashion industry stock market index, the news topic index, and macro-economic indicators. The results indicated the topics of "Cosmetic business expansion" and "Digital innovation" impacted the Textile & Wearing Apparel KOSPI after one week, and the topics of "Pop-up store," "Entry into the Chinese fashion market," and "Fashion week and trade show" affected it after two weeks. Moreover, the topics of "Cosmetic business expansion" and "Entry into the Chinese fashion market" were statistically significant in the macroeconomic environment. Regarding the effect relation of Textile & Wearing Apparel KOSPI, "Cosmetic business expansion," "Entry into the Chinese fashion market," and consumer price fluctuation showed negative effects, while the private consumption change rate, producer price fluctuation, and unemployment change rate had positive effects. This study analyzes the impact of media framing on fashion industry business cycles and provides practical insights into managing stock market risk for fashion companies.

Arithmetic Fluctuation Effect affected by Induced Emotional Valence (유발된 정서가에 따른 계산 요동의 효과)

  • Kim, Choong-Myung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.2
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    • pp.185-191
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    • 2018
  • This study examined the type and extent of interruption between induced emotion and succeeding arithmetic operation. The experiment was carried out to determine the influence of the induced emotions (anger, joy, and sorrow) and stimulus types (picture and sentence) on the cognitive process load that may block the interactions among the constituents of working memory. The study subjects were 32 undergraduates who were similar with respect to age and education parameters and were especially instructed to attend to induced emotion by imitation of facial expression and to make a correct decision during the remainder calculation task. In the results, the stimulus types did not exhibit any difference but there was a significant difference among the induced emotion types. The difference was observed in slower response time at positive emotion(joy condition) as compared with other emotions(anger and sorrow). More specifically, error and delayed correct response rate for emotion types were analysed to determine which phase the slower response was associated with. Delayed responses of the joy condition by sentence-inducing stimulus were identified with the error rate difference, and those by picture-inducing stimulus with the delayed correct response rate. These findings not only suggest that induced positive emotion increased response time compared to negative emotions, but also imply that picture-inducing stimulus easily affords arithmetic fluctuation whereas sentence-inducing stimulus results in arithmetic failure.

Influence of Smoking Cessation on Periodontal Biomarkers in Gingival Crevicular Fluid for 1 Year: A Case Study (1년간 금연이 미치는 치은열구액 내 치주염 바이오마커 변화: 사례연구)

  • Hwang, Soo-Jeong
    • Journal of dental hygiene science
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    • v.14 no.4
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    • pp.525-536
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    • 2014
  • Although tobacco use has been known as one of the biggest risk factors on periodontal health, little is known about the effect of smoking cessation on it. The aim of this study was to investigate the change of concentration of matrix metalloproteinase (MMP)-8, MMP-9 and interleukin (IL)-$1{\beta}$ in gingival crevicular fluid (GCF) of 11 quit-smokers for 1 year after smoking cessation. Eleven male subjects to maintain quit-smoking for 1 year participated the oral examination, GCF and saliva collection without periodontal treatments at baseline, after 2 weeks, 2 months, 4 months, 6 months and 1 year. To confirm quit-smoking, nicotine and cotinine concentrations in saliva were measured by high performance liquid chromatography. MMP-8, MMP-9 and IL-$1{\beta}$ concentrations in GCF of upper anterior teeth area were measured by enzyme-linked immunosorbent assay. Change of MMP-8 in GCF during smoking cessation showed fluctuation with decrease (5 subjects) or increase (2 subjects) or maintenance tendency (4 subjects). Changes of MMP-9 were decrease (6 subjects), or increase (2 subjects), or maintenance (3 subjects). Change of IL-$1{\beta}$ also showed fluctuation with decrease (5 subjects) or increase (3 subjects) or maintenance tendency (3 subjects). The subjects with increase tendency had the relatively smaller amount concentration of MMP-8 and MMP-9 at the baseline. It was unclear smoking cessation without periodontal treatment could affect MMP-8, MMP-9, and IL-$1{\beta}$ in GCF. Fluctuation of periodontal biomarkers during smoking cessation might result from feedback interaction between environmental factors and periodontal cells.

Effect of Temperature Fluctration and Different Stocking Densities on Mortality of Sea Squirt, Halocynthia roretzi(von Drasche) (온도자극 및 수용밀도에 따른 우렁쉥이 폐사)

  • 홍정표;김영섭;허성범
    • Journal of Aquaculture
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    • v.13 no.4
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    • pp.285-293
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    • 2000
  • Mortality suffered by the sea squirt in indoor experiment was higher at the stocking density of 12 kg than that at 3 and 6 kg. Daily mortality was also higher at 8 t:: thermal fluctuation than that at 3 and 5$^{\circ}C$. The thermal fluctuation observed at the depth of 5 m during June was higher, i.e. 7.4$^{\circ}C$ but it was just 2-4$^{\circ}C$ during mid-May. It did not fluctuate at all during the period from January to February. Mortality was higher at the stocking density of 12 kg during June than at 10 and 15 m depth.

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An Empirical Study for the Existence of Long-term Memory Properties and Influential Factors in Financial Time Series (주식가격변화의 장기기억속성 존재 및 영향요인에 대한 실증연구)

  • Eom, Cheol-Jun;Oh, Gab-Jin;Kim, Seung-Hwan;Kim, Tae-Hyuk
    • The Korean Journal of Financial Management
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    • v.24 no.3
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    • pp.63-89
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    • 2007
  • This study aims at empirically verifying whether long memory properties exist in returns and volatility of the financial time series and then, empirically observing influential factors of long-memory properties. The presence of long memory properties in the financial time series is examined with the Hurst exponent. The Hurst exponent is measured by DFA(detrended fluctuation analysis). The empirical results are summarized as follows. First, the presence of significant long memory properties is not identified in return time series. But, in volatility time series, as the Hurst exponent has the high value on average, a strong presence of long memory properties is observed. Then, according to the results empirically confirming influential factors of long memory properties, as the Hurst exponent measured with volatility of residual returns filtered by GARCH(1, 1) model reflecting properties of volatility clustering has the level of $H{\approx}0.5$ on average, long memory properties presented in the data before filtering are no longer observed. That is, we positively find out that the observed long memory properties are considerably due to volatility clustering effect.

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Effects of Acupuncture at HapGuk$(LI_4)$ on Pain in Rats (합곡(合谷) 침자극(鍼刺戟)이 동통억제(疼痛抑制)에 미치는 영향(影響))

  • Hwang Woo-Jun;Park Jong-Ju
    • Journal of Acupuncture Research
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    • v.15 no.2
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    • pp.369-382
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    • 1998
  • The purpose of this study was finding the pain inhibitory effect of acupuncture at $LI_4$. The pain at dentes incisivi was evoked by noxious electric stimulation and EMG changes based on the interval were measured. To do this, the opioid antagonist was administered intraperitoneally. Following are some of results. 1. The pain inhibitory effect of acupuncture at $LI_4$ was 94.35%, 84.56%, 57.62%, 54.40%, at 10, 20, 30 and 40 minutes respectively. All the data were calculated based on 100% at 0 minute. The effect was very significant at 40 minutes. 2. The continuous effect of acupuncture at $LI_4$ after taking out the needle was 58.58%, 57.62%, 66.22%, 73.18%, 83.70%, 92.68%, at 50, 50, 70, 80, 90 and 100 minutes respectively. The overall continuous effect was shown its maximum 20 minutes after taking out the needle and reached to the initial value at 60 minutes. 3. The pain inhibitory effect following the naloxone administration and acupuncture application at $LI_4$ was 95.96%, 96.04%, 94.86%, 94.92% at 10, 20, 30 and 40 minutes respectively. All values showed similar tendency to the initial data. 4. The continuous effect of acupuncture at $LI_4$ after taking out the needle which was preceded by the naloxone administration was 94.48%, 96.02%, 96.02%, 98.00%, 98.46%, 97.18% at 50, 60, 70, 80, 90 and 100 minutes respectively. This trend was not a significant fluctuation. It was concluded that effect of acupuncture at $LI_4$ was shown in conjunction with secretion of analgesic substance. Therefore it is implied that the acupuncture application will play a major role in treating many diseases with more revelation of scientific acupuncture mechanism. Further studies of acupuncture manipulation are needed in the future based on our study.

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Effects of Acupuncture at Chok-samni(ST36) on Pain in Rats (족삼리(足三里) 침자(鍼刺)가 동통억제(疼痛抑制)에 미치는 영향(影響))

  • Sin Gun-Seong;Byun Jae-Young;Ahn Soo-Gi;Hwang Woo-Jun
    • Journal of Acupuncture Research
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    • v.15 no.2
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    • pp.287-300
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    • 1998
  • The purpose of this study was finding the pain inhibitory effect of acupuncture at ST-36. The pain at dentes incisor was evoked by noxious electric stimulation and EMG changes based on time interval were measured. To do this, the opioid antagonist was administered intraperitoneally. Followings are some of the results. 1. The pain inhibitory effect of acupuncture at ST-36 was 93.82%, 87.00%, 75.30%, 69.76% at 10 20, 30 and 40 minutes respectively. All the data were calculated based on 100% at 0 minute. The effect was very significant at 40 minutes. 2. The continuous effect of acupuncture at ST-36 after taking out the needle was 77.46%, 79.66%, 87.60%, 91.50%, 95.14%, 99.48% at 50, 60, 70, 80, 90 and 100 minutes respectively. The overall continuous effect was shown its maximum 20 minutes after taking out the needle and reached to the initial value at 60 minutes. 3. The pain inhibitory effect following the naloxone administration and acupuncture application ST-36 was 93.44%, 94.58%, 90.80%, 88.04% at 10, 20, 30 and 40 minutes respectively. All values showed similar tendency to the initial data. 4. The continuous effect of acupuncture at ST-36 after taking out the needle which was preceded by the naloxone administration was 91.26%, 91.90%, 92.06%, 93.66%, 94.12%, 93.50% at 50, 60, 70, 80, 90 and 100 minutes respectively. This trend was not a significant fluctuation. It Was concluded that effect of acupuncture at ST-36 was shown in conjunction with secretion of analgesic substance. Therefore it is implied that the acupuncture application will play a major role in treating many diseases with more revelation of scientific acupuncture mechanism. Further studies of acupuncture manipulation are needed in the future based on our study.

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