• Title/Summary/Keyword: Stress Field

Search Result 3,038, Processing Time 0.038 seconds

Numerical Analysis on the Influence Factors of Cavity Occurrence in the Stability of the Underground with Cavity (도로 하부지반에서 발생된 공동이 지반 안정성에 미치는 영향에 관한 수치해석)

  • Nam, Jun-Hee;Kim, Jong-Chul;Lee, Kang-Il
    • Journal of the Korean Geosynthetics Society
    • /
    • v.21 no.1
    • /
    • pp.49-56
    • /
    • 2022
  • In this study, finite element numerical analysis was performed considering various influence factors(cavity shape and size, pavement thickness and size of traffic load) in order to analyze the impact factors in the underground of the road where the cavity occurred and to evaluate the stability of the ground. In order to verify the reliability of the numerical analysis method applied in this study and the results it was compared and analyzed with the results of previous studies and field measurements. The correlation between the influence factors was analyzed through the distribution of vertical displacement obtained from the numerical analysis results, the distribution of surface settlement and surface settlement, the distribution of the stress ratio, and the distribution of the safety factor. As a result, it was confirmed that as the size of the cavity and traffic load increased and the thickness of the pavement decreased, the vertical displacement and surface settlement at the top of the cavity increased. Also, the shape of the cavity was square, the stability of the ground was significantly reduced compared to the case of a circular cavity. Through these results, it was possible to confirm the overall stability of the lower ground of the road where the cavity was generated.

Counseling Outcomes Research Trend Analysis Using Topic Modeling - Focus on 「Korean Journal of Counseling」 (토픽 모델링을 활용한 상담 성과 연구동향 분석 - 「상담학연구」 학술지를 중심으로)

  • Park, Kwi Hwa;Lee, Eun Young;Yune, So Jung
    • Journal of Digital Convergence
    • /
    • v.19 no.11
    • /
    • pp.517-523
    • /
    • 2021
  • The outcome of the consultation is important to both the counselor and the researcher. Analyzing the trends of research on the results of counseling that have been carried out so far will help to comprehensively structure the results of consultations. The purpose of this research is to analyze research trends in Korea, focusing on research related to the outcomes of counseling published in 「Korean Journal of Counseling」 from 2011 to 2021, which is one of the well-known academic journals in the field of counseling in Korea. This is to explore the direction of future research by navigating the knowledge structure of research. There were 197 studies used for analysis, and the final 339 keyword were extracted during the node extraction process and used for analysis. As a result of extracting potential topics using the LDA algorithm, "Measurement and evaluation of counseling outcomes", "emotions and mediate factors affecting interpersonal relationships", and "career stress and coping strategies" are the main topics. Identifying major topics through trend analysis of counseling performance research contributed to structuring counseling performance. In-depth research on these topics needs to continue thereafter.

Research Trends on Emotional Labor in Korea using text mining (텍스트마이닝을 활용한 감정노동 연구 동향 분석)

  • Cho, Kyoung-Won;Han, Na-Young
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.26 no.6
    • /
    • pp.119-133
    • /
    • 2021
  • Research has been conducted in many fields to identify research trends using text mining, but in the field of emotional labor, no research has been conducted using text mining to identify research trends. This study uses text mining to deeply analyze 1,465 papers at the Korea Citation Index (KCI) from 2004 to 2019 containing the subject word 'emotional labor' to understand the trend of emotional labor researches. Topics were extracted by LDA analysis, and IDM analysis was performed to confirm the proportion and similarity of the topics. Through these methods, an integrated analysis of topics was conducted considering the usefulness of topics with high similarity. The research topics are divided into 11 categories in descending order: stress of emotional labor (12.2%), emotional labor and social support (12.0%), customer service workers' emotional labor (10.9%), emotional labor and resilience (10.2%), emotional labor strategy (9.2%), call center counselor's emotional labor (9.1%), results of emotional labor (9.0%), emotional labor and job exhaustion (7.9%), emotional intelligence (7.1%), preliminary care service workers' emotional labor (6.6%), emotional labor and organizational culture (5.9%). Through topic modeling and trend analysis, the research trend of emotional labor and the academic progress are analyzed to present the direction of emotional labor research, and it is expected that a practical strategy for emotional labor can be established.

Comparison of Liquefaction Assessment Results with regard to Geotechnical Information DB Construction Method for Geostatistical Analyses (지반 보간을 위한 지반정보DB 구축 방법에 따른 액상화 평가 결과 비교)

  • Kang, Byeong-Ju;Hwang, Bum-Sik;Bang, Tea-Wan;Cho, Wan-Jei
    • Journal of the Korean Geotechnical Society
    • /
    • v.38 no.4
    • /
    • pp.59-70
    • /
    • 2022
  • There is a growing interest in evaluating earthquake damage and determining disaster prevention measures due to the magnitude 5.8 earthquake in Pohang, Korea. Since the liquefaction phenomena occurred extensively in the residential area as a result of the earthquake, there was a demand for research on liquefaction phenomenon evaluation and liquefaction disaster prediction. Liquefaction is defined as a phenomenon where the strength of the ground is completely lost due to a sudden increase in excess pore water pressure caused due to large dynamic stress, such as an earthquake, acting on loose sand particles in a short period of time. The liquefaction potential index, which can identify the occurrence of liquefaction and predict the risk of liquefaction in a targeted area, can be used to create a liquefaction hazard map. However, since liquefaction assessment using existing field testing is predicated on a single borehole liquefaction assessment, there has been a representative issue for the whole targeted area. Spatial interpolation and geographic information systems can help to solve this issue to some extent. Therefore, in order to solve the representative problem of geotechnical information, this research uses the kriging method, one of the geostatistical spatial interpolation techniques, and constructs a geotechnical information database for liquefaction and spatial interpolation. Additionally, the liquefaction hazard map was created for each return period using the constructed geotechnical information database. Cross validation was used to confirm the accuracy of this liquefaction hazard map.

Intervention of Nonsuicidal Self-Injury in School Counseling (비자살성 자해(NSSI)에 대한 학교상담에서의 개입)

  • Ryu, Shinhye;Bae, Seung Min;Jun, Jin Yong;Im, Woo-Young
    • Korean Journal of Psychosomatic Medicine
    • /
    • v.30 no.1
    • /
    • pp.1-6
    • /
    • 2022
  • Recently, nonsuicidal self-injury (NSSI) has been increasing considerably in school counseling. According to the Youth Counseling and Welfare Development Institute, the number of counseling support for NSSI adolescent in 2018 was more than three times higher than the previous year, and the average time when NSSI behavior first appeared was 12.43 years old. As such, adolesnect NSSI continues to increase in recent years, and the age is also gradually decreasing. Nevertheless, research on the motives and characteristics of NSSI among domestic adolescents is still insufficient. This may be attributed to the difficulty of conducting research because self-injury behavior is secretly performed. However, it is also true that this reality has another limitation in the school field, which urgently requires counseling intervention and prevention of students' mental health problems. In addition, counseling for self-injury in the school scene is the biggest cause of exhaustion for counselors because they are under very great stress to cope with repeated self-harm in the dual role of counselors and teachers in school situations. Therefore, this study examines the causes and characteristics of involuntary self-injury through previous research analysis, and examines various difficulties experienced as a school counselor, as well as the effective intervention method of non suicidal self-injury in school counseling.

Ginsenoside Rg1 attenuates cerebral ischemia-reperfusion injury due to inhibition of NOX2-mediated calcium homeostasis dysregulation in mice

  • Han, Yuli;Li, Xuewang;Yang, Liu;Zhang, Duoduo;Li, Lan;Dong, Xianan;Li, Yan;Qun, Sen;Li, Weizu
    • Journal of Ginseng Research
    • /
    • v.46 no.4
    • /
    • pp.515-525
    • /
    • 2022
  • Background: The incidence of ischemic cerebrovascular disease is increasing in recent years and has been one of the leading causes of neurological dysfunction and death. Ginsenoside Rg1 has been found to protect against neuronal damage in many neurodegenerative diseases. However, the effect and mechanism by which Rg1 protects against cerebral ischemia-reperfusion injury (CIRI) are not fully understood. Here, we report the neuroprotective effects of Rg1 treatment on CIRI and its possible mechanisms in mice. Methods: A bilateral common carotid artery ligation was used to establish a chronic CIRI model in mice. HT22 cells were treated with Rg1 after OGD/R to study its effect on [Ca2+]i. The open-field test and poleclimbing experiment were used to detect behavioral injury. The laser speckle blood flowmeter was used to measure brain blood flow. The Nissl and H&E staining were used to examine the neuronal damage. The Western blotting was used to examine MAP2, PSD95, Tau, p-Tau, NOX2, PLC, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging was used to test the level of [Ca2+]i. Results: Rg1 treatment significantly improved cerebral blood flow, locomotion, and limb coordination, reduced ROS production, increased MAP2 and PSD95 expression, and decreased p-Tau, NOX2, p-PLC, CN, NFAT1, and NLRP1 expression. Calcium imaging results showed that Rg1 could inhibit calcium overload and resist the imbalance of calcium homeostasis after OGD/R in HT22 cells. Conclusion: Rg1 plays a neuroprotective role in attenuating CIRI by inhibiting oxidative stress, calcium overload, and neuroinflammation.

Structural Performance Evaluation of a Multi-span Greenhouse with Venlo-type Roof According to Bracing Installation (가새 설치에 따른 벤로형 지붕 연동온실의 구조성능 평가)

  • Shin, Hyun Ho;Choi, Man Kwon;Cho, Myeong Whan;Kim, Jin Hyun;Seo, Tae Cheol;Lee, Choung Kuen;Kim, Seung Yu
    • Journal of Bio-Environment Control
    • /
    • v.31 no.4
    • /
    • pp.438-443
    • /
    • 2022
  • In this study, the lateral loading test was performed to analyze structural performance of multi-span plastic greenhouse through full-scale experiment and numerical analysis. In order to analyze the lateral stiffness and stress, we installed 9 displacement sensors and 19 strain gauge sensors on the specimen, respectively, and load of l mm per minute was applied until the specimen failure. In the comparison between the full-scale experiment and the structural analysis results of a multi-span greenhouse with venlo-type roof according to bracing installation, there was a large difference in the lateral stiffness of the structure. By installing a brace system, the lateral stiffness measured near the side elevation of the specimen increased by up 44%. As the bracing joint used in the field did not secure sufficient rigidity, the external force could not be transmitted to the entire structure properly. Therefore, it is necessary to establish a bracing construction method and design standards in order for a greenhouse to which bracing applied to have sufficient performance.

Research Status of Satellite-based Evapotranspiration and Soil Moisture Estimations in South Korea (위성기반 증발산량 및 토양수분량 산정 국내 연구동향)

  • Choi, Ga-young;Cho, Younghyun
    • Korean Journal of Remote Sensing
    • /
    • v.38 no.6_1
    • /
    • pp.1141-1180
    • /
    • 2022
  • The application of satellite imageries has increased in the field of hydrology and water resources in recent years. However, challenges have been encountered on obtaining accurate evapotranspiration and soil moisture. Therefore, present researches have emphasized the necessity to obtain estimations of satellite-based evapotranspiration and soil moisture with related development researches. In this study, we presented the research status in Korea by investigating the current trends and methodologies for evapotranspiration and soil moisture. As a result of examining the detailed methodologies, we have ascertained that, in general, evapotranspiration is estimated using Energy balance models, such as Surface Energy Balance Algorithm for Land (SEBAL) and Mapping Evapotranspiration with Internalized Calibration (METRIC). In addition, Penman-Monteith and Priestley-Taylor equations are also used to estimate evapotranspiration. In the case of soil moisture, in general, active (AMSR-E, AMSR2, MIRAS, and SMAP) and passive (ASCAT and SAR)sensors are used for estimation. In terms of statistics, deep learning, as well as linear regression equations and artificial neural networks, are used for estimating these parameters. There were a number of research cases in which various indices were calculated using satellite-based data and applied to the characterization of drought. In some cases, hydrological cycle factors of evapotranspiration and soil moisture were calculated based on the Land Surface Model (LSM). Through this process, by comparing, reviewing, and presenting major detailed methodologies, we intend to use these references in related research, and lay the foundation for the advancement of researches on the calculation of satellite-based hydrological cycle data in the future.

Autonomic Nerve Change after Loess Bedding Radiating Far-infrared ray and energy (원적외선에너지 방출 황토침구 사용 후의 자율신경 변화에 대한 연구)

  • Lee, Ku Yeon;Lee, Hyung H.;Hahm, Suk Chan
    • Journal of Naturopathy
    • /
    • v.9 no.1
    • /
    • pp.27-32
    • /
    • 2020
  • Purpose: The purpose of this study was to investigate the changes in the autonomic nervous system of the human body after the use of ocher bedding radiating far-infrared rays to 15 insomnia subjects. Methods: Changes of autonomous nerve in the subjects after using loess bedding estimated by heart rate variability. Results: The mean HF before the use of ocher bedding was 220.8 msec2, and the mean after use decreased to 5.1 msec2. The average value of LF before use was 418.1 msec2, and the mean after use decreased to 5.2 msec2. The average before use of the VLF was 1463.3 msec2, and the average after use dropped to 6.8 msec2. The average value of TP before use was 977.3 msec2, and the average after use dropped to 6.7 msec2. The decrease in postoperative values of all four items was statistically significant, and the high value of the subjects before use inferred to be the reason that all of the subjects had high stress and anxiety due to their long-term sleep disorder. There was no significant difference in the pulses of the subjects before the use of the bedding. SDNN and RMSSD were not significantly different before and after use. Conclusions: Autonomic nerves HF, LF, VLF, TP frequency is evaluated to be affected by the investigation of far-infrared radiation that occurs ocher. This research data regarded as high value as primary data in this field.

Cold Hardiness Change in Solenopsis japonica (Hymenoptera: Formicidae) by Rapid Cold Hardening (급속내한성 유기에 의한 일본열마디개미(Solenopsis japonica)의 내한성 변화)

  • Park, Youngjin;Vatanparast, Mohammad;Lee, Jieun
    • Korean journal of applied entomology
    • /
    • v.60 no.2
    • /
    • pp.193-199
    • /
    • 2021
  • Solenopsis japonica, which is belonging to Formicidae in Hymenoptera, is a native ant species in Korea. However, it had not been studied for cold hardiness of S. japonica to understand on its overwintering mechanisms in field so far. Cold tolerance on developmental stages was measured at different cold temperature with various exposure times. Workers showed more survival at 5℃ and 10℃ compared with other stages and elevated cold tolerance when workers were exposed at 15℃ for more than 12h incubation as a rapid cold hardening (RCH) condition. RCH treatment not only increased survival of workers at cold temperatures, but also decreased supercooling point (SCP) and freezing point (FP). RCH group increased the survival rate by 44% at 10℃ compared with Non-RCH group. SCP and FP were depressed from -10.0 to -14.2℃ and from -11.3 to -15.3℃, respectively, after RCH treatment. Cold temperature increased expression level of cold- and stress-related genes such as glycerol kinase and heat shock protein. These results indicate unacclimated cold tolerance of S. japonica and its acclimation to low temperature by RCH.