• 제목/요약/키워드: pressure history

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Mechanical behavior of coiled tubing over wellhead and analysis of its effect on downhole buckling

  • Zhao, Le;Gao, Mingzhong;Li, Cunbao;Xian, Linyun
    • Steel and Composite Structures
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    • v.44 no.2
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    • pp.199-210
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    • 2022
  • This study build finite element analysis (FEA) models describing the bending events of coiled tubing (CT) at the wellhead and trips into the hole, accurately provide the state of stress and strain while the CT is in service. The bending moment and axial force history curves are used as loads and boundary conditions in the diametrical growth models to ensure consistency with the actual working conditions in field operations. The simulation diametrical growth results in this study are more accurate and reasonable. Analysis the factors influencing fatigue and diametrical growth shows that the internal pressure has a first-order influence on fatigue, followed by the radius of the guide arch, reel and the CT diameter. As the number of trip cycles increase, fatigue damage, residual stress and strain cumulatively increase, until CT failure occurs. Significant residual stresses remain in the CT cross-section, and the CT exhibits a residual curvature, the initial residual bending configuration of CT under wellbore constraints, after running into the hole, is sinusoidal. The residual stresses and residual bending configuration significantly decrease the buckling load, making the buckling and buckling release of CT in the downhole an elastic-plastic process, exacerbating the helical lockup. The conclusions drawn in this study will improve CT models and contribute to the operational and economic success of CT services.

Multimetric Measurement Data Monitoring System Using Sigmoid Function (시그모이드 함수를 이용한 다중 계측데이터 모니터링 시스템)

  • Jeong-Ho Song;Jun-Woo Shin;Heui-Soo Han
    • The Journal of Engineering Geology
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    • v.33 no.1
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    • pp.137-149
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    • 2023
  • In order to intuitively grasp the earth pressure direction acting on the structure and displacement state, displacement data in the horizontal and vertical directions were processed using the sigmoid function. A displacement coordinate system was set up for each axis. The system can intuitively check the current displacement and assess the management stage of each point. A displacement path can be compiled from continuously recorded points, allowing trends in the displacement's history and stress direction to be known. Analysis of data measured for excavated ground, found that displacement occurred in the direction of destressing at all points, and that the points' management state steady. Similar behavior trends were found among measurement points with high spatial correlation, whereas differing behavior trends occurred among measurement points with low spatial correlation. If the correlation analysis of the precursor and behavior area is performed using the continuously distributed surface settlement data and displacement coordinate system, it will be possible to predict the failure time and area.

Past and Future Epidemiological Perspectives and Integrated Management of Rice Bakanae in Korea

  • Soobin, Shin;Hyunjoo, Ryu;Yoon-Ju, Yoon;Jin-Yong, Jung;Gudam, Kwon;Nahyun, Lee;Na Hee, Kim;Rowoon, Lee;Jiseon, Oh;Minju, Baek;Yoon Soo, Choi;Jungho, Lee;Kwang-Hyung, Kim
    • The Plant Pathology Journal
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    • v.39 no.1
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    • pp.1-20
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    • 2023
  • In the past, rice bakanae was considered an endemic disease that did not cause significant losses in Korea; however, the disease has recently become a serious threat due to climate change, changes in farming practices, and the emergence of fungicide-resistant strains. Since the bakanae outbreak in 2006, its incidence has gradually decreased due to the application of effective control measures such as hot water immersion methods and seed disinfectants. However, in 2013, a marked increase in bakanae incidence was observed, causing problems for rice farmers. Therefore, in this review, we present the potential risks from climate change based on an epidemiological understanding of the pathogen, host plant, and environment, which are the key elements influencing the incidence of bakanae. In addition, disease management options to reduce the disease pressure of bakanae below the economic threshold level are investigated, with a specific focus on resistant varieties, as well as chemical, biological, cultural, and physical control methods. Lastly, as more effective countermeasures to bakanae, we propose an integrated disease management option that combines different control methods, including advanced imaging technologies such as remote sensing. In this review, we revisit and examine bakanae, a traditional seed-borne fungal disease that has not gained considerable attention in the agricultural history of Korea. Based on the understanding of the present significance and anticipated risks of the disease, the findings of this study are expected to provide useful information for the establishment of an effective response strategy to bakanae in the era of climate change.

A Case of Choroidal Melanocytoma with Optic Nerve Involvement in a Dog

  • Jinseon Chang;Dajeong Jeong;Seonmi Kang;Kangmoon Seo
    • Journal of Veterinary Clinics
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    • v.40 no.4
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    • pp.283-287
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    • 2023
  • A 10-year-old spayed female beagle dog presented with a 2-month history of third-eyelid elevation in the left eye (OS). Ophthalmic examination revealed slightly diminished corneal and palpebral reflexes along with exophthalmos in the OS. Schirmer's tear test and intraocular pressure values were within the normal range for the OS. Slit-lamp biomicroscopy revealed protrusion of the third eyelid and corneal opacity in the OS. Fundoscopy revealed a prominent black mass in the OS covering the optic nerve. Tapetal hyper-reflectivity was also observed around the mass. Ocular ultrasonography showed a 0.74 × 0.67 cm echogenic posterior segment mass around the optic nerve protruding into the retrobulbar space. Computed tomography revealed a contrast-enhanced soft tissue lesion in the posteromedial aspect of the left eyeball protruding into the retrobulbar region, and the optic nerve was suspected to be involved. No evidence of osteolytic changes in the adjacent bone or distant metastasis was observed. Enucleation was performed to prevent potential metastasis or local invasion of the mass and to relieve discomfort due to exposure to keratopathy resulting from lagophthalmos. Histopathological examination revealed a central choroidal melanocytoma extending into the optic nerve. No local recurrence was detected until 16 months postoperatively.

Correlation between shift work and non-alcoholic fatty liver disease among male workers in the steel manufacturing company of Korea: a cross-sectional study

  • Kiseok Kim;Yong-Jin Lee;Soon-Chan Kwon;Young-Sun Min;Hyun Kyo Lee;Gwangin Baek;Sang Hyeon Kim;Eun-Chul Jang
    • Annals of Occupational and Environmental Medicine
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    • v.34
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    • pp.33.1-33.13
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    • 2022
  • Background: Circadian rhythm disturbance caused by shift work has adverse effects on the metabolic homeostasis of the liver. Disruption of the metabolic homeostasis of the liver causes fat accumulation in the liver. The aim of this study was to investigate the correlation between shift work and non-alcoholic fatty liver disease (NAFLD) among male workers in the steel manufacturing industry of Korea. Methods: Based on medical examination data collected in June 2020, 2,511 male subjects from one steel manufacturing company in Korea were selected in total. NAFLD was evaluated using abdominal ultrasound, which was performed by two experienced radiologists. The multinomial logistic regression analysis was performed by adjusting for age, physical activity, smoking history, alcohol consumption, body mass index, waist circumference, blood pressure, blood glucose, lipidemia, liver function test, employment duration, and hepatotoxic materials exposure status. Results: Compared to daytime workers, the odds ratio (OR) of moderate-severe NAFLD in shift workers was 1.449 (95% confidence interval [CI], 1.028-2.043). Compared to daytime workers, the ORs of moderate-severe NAFLD were significantly higher for the group that engaged in total shift work for more than 20 years (OR, 2.285; 95% CI, 1.051-4.970), the group that was not allowed to sleep during night shift work (OR, 1.463; 95% CI, 1.030-2.078), and the group that consumed food during night shift work (OR, 1.580; 95% CI, 1.093-2.284). Conclusions: There was a correlation between shift work and moderate-severe NAFLD in male steel manufacturing workers. There will be a need for more research related to the correlation of shift work with steatohepatitis and cirrhosis in the future.

The risk of confusion between AstraZeneka COVID-19 vaccine side effects and signs of COVID-19 infection: a case report

  • Mahin Nomali;Mahdieh Afzali
    • Clinical and Experimental Vaccine Research
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    • v.11 no.1
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    • pp.125-128
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    • 2022
  • Post-vaccination side effects of AstraZeneca (AZ) coronavirus disease 2019 (COVID-19) vaccine are common. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection immediately after the first dose of AZ COVID-19 vaccine has not been reported. In this case, a 30-year-old female without a past medical history of SARS-CoV2 infection presented to an outpatient clinic with lightheadedness and weakness 2 hours after getting the first dose of the AZ COVID-19 vaccine. Blood pressure (BP) was 80/60 mm Hg, and oxygen saturation (SpO2) was 98%. After administering normal saline intravenous fluid, the BP was 110/80 mm Hg. On the first day, fever (oral temperature of 39℃), sweating, dry cough, sore throat, and injection-site pain were presented. On the second day, diarrhea, productive cough, and hypotension occurred in addition to fever (oral temperature of 39.9℃). The fever did not stop and productive cough, change in smell, and fatigue were reported. SpO2 was 96%. On the third day, no abnormality of the spiral lung computed tomography and the positive reverse transcriptase-polymerase chain reaction (RT-PCR) test were reported. Simultaneously, two out of three members of the family became symptomatic on the second day and their RT-PCR tests were positive. Dexamethasone ampule, Cefixime tablet, Acetaminophen tablet, and Diphenhydramine syrup were prescribed. After a week, fever subsided and SpO2 was 98%. After 3 weeks of self-quarantine at home, her general condition improved. Despite the similarity between SARS-CoV2 infection signs and symptoms and AZ COVID-19 vaccine side effects, none of the approved vaccines contain the live virus that causes disease. Therefore, any unusual post-vaccination signs and symptoms should not be attributed to the vaccine itself and need to be considered for further evaluations and early actions in order to prevent the spread of the disease in society.

Impact of Weather on Prevalence of Febrile Seizures in Children (소아의 열성경련에 날씨가 미치는 영향)

  • Woo, Jung Hee;Oh, Seok Bin;Yim, Chung Hyuk;Byeon, Jung Hye;Eun, Baik-Lin
    • Journal of the Korean Child Neurology Society
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    • v.26 no.4
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    • pp.227-232
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    • 2018
  • Purpose: Febrile seizure (FS) is the most common type of seizure in children between 6 months to 5 years of age. A family history of febrile seizures can increase the risk a child will have a FS. Yet, prevalence of FS regarding external environment has not been clearly proved. This study attempts to determine the association between prevalence of FS and weather. Methods: This study included medical records from the Korea National Health Insurance Review and Assessment Service. Data were collected from 29,240 children, born after 2004, diagnosed with FS who were admitted to one of the hospitals in Seoul, Korea, between January 2009 and December 2013. During the corresponding time period, data from the Korea Meteorological Administration on daily monitoring of four meteorological factors (sea-level pressure, amount of precipitation, humidity and temperature) were collected. The relationships of FS prevalence and each meteorological factor will be designed using Poisson generalized additive model (GAM). Also, the contributory effect of viral infections on FS prevalence and weather will be discussed. Results: The amount of precipitation was divided into two groups for comparison: one with less than 5 mm and the other with equal to or more than 5 mm. As a result of Poisson GAM, higher prevalence of FS showed a correlation with smaller amount of precipitation. Smoothing function was used to classify the relationships between three variables (sea-level pressure, humidity, and temperature) and prevalence of FS. FS prevalence was correlated with lower sea-level pressure and lower humidity. FS prevalence was high in two temperature ranges (-7 to $-1^{\circ}C$ and $18-21^{\circ}C$). Conclusion: Low sea-level pressure, small amount of precipitation, and low relative air humidity may increase FS prevalence risk.

Prevalence Rate of Hypertension and Cared Pattern in Rural Aged over Sixty Years Old (농촌지역 60세 이상 노인인구의 고혈압 유병율 및 관리형태)

  • Lim, Song;Chun, Byung-Yeol;Yeh, Min-Hae
    • Journal of agricultural medicine and community health
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    • v.19 no.2
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    • pp.129-140
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    • 1994
  • The survey has for its object to detect prevalence rate of hypertension in target population, to find out the risk factor to hypertension, to detect the hypertensive patients cared pattern and therefore, to consider a effective counter plan for the long term about hypertension. The study, population of this survey was 894 out of 1013 target population from Feb. 1 1994 to March 31 1994 in Kyougsang-namdo Ulsan-gun Samnam-myoun. For these two month, check of blood pressure and direct measurement of height and weight was carried out by mass screening and home visiting and had an interview about risk factors for hypertension and cared pattern by questionnaire. The results of survey were as follows : 1. The prevalence rate of 894 study, population was 27.5% and 26.0% in man and 28.6% in women. 2. In male, the prevalence rate for age group, family history of hypertension, drinking, salt intake by risk factors were significant statistically. 3. In female, the prevalence rate for salt intake, body mass index by risk factors were significant statistically. 4. Motivation which was diagnosed as hypertension was that be examined for subjective symptoms of hypertension and routine check for health was only 25.0%, 9.1% and visiting to the hospital for other diseases, detect hypertension by chance was 65.9%. 5. The experience of treatment in prevalent cases was significant statistically in middle class of SES. And the place of treatment by risk factors could not be significant statistically in spite of the majority selected hospital generally. 6. The reasons of non-compliance in prevalent cases was restricting daily activities for its 45.5% most high and the interruption of treatment in prevalent cases was far from hospital geographically for its 47.6% most high 7. The preventive behavior about hypertensive by risk factors or general characteristics wasn't significant statistically. 8. Being treated or not in the near future about age group, SES, family history of the hypertension was significant statistically. And with regard to the place of treatment in the near future, in spite of the majority selected hospital generally, it wasn't significant statistically. 9. The reasons of non-compliance in incidence cases was restricting daily activities for its 46.8% most high. 10. The preventive behavior in the near future about age group, education level, SES, family history of hypertension was significant statistically.

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Morbidity Pattern of Residents in Urban Poor Area by Health Screening (도시 영세지역 주민의 건강진단 결과)

  • Kim, Chang-Yoon;SaKong, Jun;Kim, Seok-Beom;Kang, Pock-Soo;Chung, Jong-Hak
    • Journal of Yeungnam Medical Science
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    • v.8 no.2
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    • pp.150-157
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    • 1991
  • The purpose of the this study was to assess the morbidity pattern of urban residents in the poor area by health screening for the community diagnosis. The items of health screening were history taking and physical examination by medical doctor and hearing test, check blood pressure, test for hematocrit, liver function(sGOT, sGPT), urine sugar and protein, and chest X-ray. The examinee in health screening were 437 persons and they occupied 16.9% of total residents in the poor area. Male examinee were 129 persons(9.9% of total residents) and female examinee were 308 persons(23.9% of total residents). Age group of above sixty years old, 42.0% of total residents in the poor area were participated, but only 5.9% were participated in age group of 10 to 19 years old. Among the 437 examinee, 191 persons(43.7%) had one or more abnormal findings in health screening. In male 38.7% had abnormal findings, and some what lower than that of female(45.8%). Age group of above sixty years had most high rate of abnormal findings(69.8%), in contrast to age group of 10 to 19 years old (10.9%). Diseases of the digestive system was the most common and which occupies 23.7% of total abnormal findings. And diseases of the circulatory system occupied 19.7%. Low hematocrit(14.6% of total participants of 437 persons) occupies the most common abnormal findings for screening test(hematocrit, blood pressure, hearing test, sGOT/sGPT, urine protein and urine sugar, chest X-ray) and high blood pressure(10.1%) occupied second, third; hearing impairment (5.5%), fourth ; abnormal liver function (4.1%), fifth ; sugar in urine (2.3%), sixth ; protein in urine(1.4%) and lastly abnormal chest X-ray (0.9%). The positive rate of abnormal findings in health screening was very high compared with morbidity rate by health interview. It is supposed that some portion of this high rate is by selection bias in examinee in health screening specially high participating rate in older age, and the other portion is due to the low socioecomic status and bad environment of the residents of the poor area. These findings will be good information for the research and development of health care system in the urban poor area.

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The Effects of Transcutaneous Electric Nerve Stimulation (TENS) on the EMG Power Spectrum and Pressure Pain Threshold (PPT) (경피성 신경자극이 근전도 Power Spectrum과 압력통각역치에 미치는 영향)

  • Kim, Cheul;Park, Moon-Soo
    • Journal of Oral Medicine and Pain
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    • v.32 no.4
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    • pp.403-411
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    • 2007
  • This investigation was carried out to evaluate the effect of Transcutaneous Electric Nerve Stimulation (TENS) to experimentally induced masticatory muscle pain and muscular fatigue. Twenty-nine healthy volunteers (18 men and 11 women, aged $26.1{\pm}4.7$ years) without past history or present symptoms of temporomandibular disorders were participated in this study. All of the subjects were randomly assigned to experimental group and control group, after at least 3 days interval, two groups were reassigned conversely. Subjects assigned to experimental group were received TENS and others assigned to control group were received sham-TENS therapy for 45 minutes, respectively. The changes of Visual Analogue Scale (VAS), Pressure Pain Threshold (PPT), and EMG power spectrum were measured on the masseter muscle both before and after sustained fatiguing contraction in each group. The major findings of this study are as follows : 1. PPTs and median frequencies of masseter muscles were significantly decreased after sustained isometric contraction resulting in muscular fatigue. 2. In experimental group received TENS therapy, PPTs measured both before and after occurrence of experimentally induced muscular fatigue were significantly increased. 3. In experimental group received TENS therapy, the changes of PPTs during sustained isometric contraction resulting in muscular fatigue were significantly decreased. 4. In experimental group received TENS therapy, VAS measured after occurrence of experimentally induced muscular fatigue was significantly decreased. 5. Although there were not statistical significances, endurance time was increased in experimental group received TENS therapy and decreased in control group received sham-TENS therapy. 6. In experimental group received TENS therapy, the changes of median frequencies were the less decreased and the slope of median frequency shift was the more increased during endurance time than in control group, however, there were not statistical significances.