• Journal of Astronomy and Space Sciences
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• 제5권2호
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• pp.97-109
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• 1988

The photometric behaviour of XY U Ma, an eclipsing binary showing photospheric and chromospheric activity, has been described by spot hypothesis. They are based on the all the available UBV light curves, which were carried out by Geyer since 1955. A "spherical rectangular" spot model shows very pronounced spot activities during the last 30 years. On the average, the spot covered about 16% of the visible hemisphere. Observational evidence for photospheric and chromospheric activities on the XY UMa and related systems are also discussed.

• 천문학회보
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• 제40권2호
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• pp.39.1-39.1
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• 2015

Korea has a long history in astronomy, which is proved by many observational records written in Korean chronicles. There are 43 sunspot records in Goryeo dynasty (高麗 918-1392) and 13 records in Joseon dynasty (朝鮮 1392-1910). According to analysis of Korean historical records, it is known that sunspot records in Goryeo dynasty show well in match with the well-known solar activity of 11.3 years. It means that Korean historical sunspot records show real solar phenomena. Korean sunspot records also show that solar activity decrease in Joseon dynasty compared with the previous ~500 years. In order to know the change of solar activity in detail, we examine Korean historical atmospheric records which can indicate climate change. We first analyze historical frost records. Korean chronicles have around 600 frost records during the last millennium. We find that the climate change shows sign of cooling down when check the variation of epoch that the first and last frost events in each year are written. This result is well in accord with that of historical sunspot records. Therefore, we claim that solar activity decrease during the last thousand years.

• 대한암한의학회지
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• 제17권1호
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• pp.27-38
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• 2012

Objective : To present an overview of current reports and guidelines of physical activity and exercise intervention for cancer survivors Methods : We searched Pubmed for the related studies such as randomized controlled trials and observational studies, as well as published guidelines or recommendations for exercise intervention. Results : Physical activity and exercise intervention is considered safe and effective for most cancer survivors. According to the guidelines, patients with peripheral neuropathy, musculoskeletal disorder, or those who are at risk of fracture, should undergo proper medical assessment before starting exercise intervention. Also, patients with bone metastasis, thrombocytopenia, symptomatic anemia, or acute infection may fall into one of the contraindications of exercise intervention. Conclusions : Physical activity and exercise intervention may play a major role in improving physical functioning, quality of life, or treatment-related symptoms of cancer survivors. It is necessary to recognize the benefits and precautions of exercise in caring cancer patients.

• 아동학회지
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• 제37권1호
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• pp.49-60
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• 2016

Objective: The purpose of the study was to explore the relationship between the daily routines and physical environments of daycare centers. Methods: A total of 20 classes at 8 different daycare centers from the metropolitan city of Daejeon were investigated. Trained observers visited each daycare center more than 3 times and collected data about daily routines using the Observational Log for Daily Routines in Daycare Centers. Also, the physical environments of each class were investigated in terms of actual size, layout of activity center, etc. Results and Conclusion: Results of the study were: first, daily routines of daycare centers could be divided into 2 distinguishable types by cluster analysis- 'free play oriented' and 'group activity oriented' Second, the amount of space each child has in a classroom differed according to the total size of the classroom. An average of 7 activity centers existed in each classroom. Third, there was a difference between free play oriented and group activity oriented groups in terms of the classroom size allocated for each child and the organization of the activity centers.

• The Journal of Asian Finance, Economics and Business
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• 제7권7호
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• pp.159-167
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• 2020

The study examines the impact of corporate social responsibility (CSR) activity on the firm market value, in particular, market capitalization of tour operators listed on Chinese stock markets. This study employs panel data analysis methods to examine endogeneity concerns in observational data. The balanced panel data includes a total of 1,296 observations with 27 cross-sections of tour operators listed on Chinese stock markets and with 48 time-specific periods from March 2006 to December 2017. The results indicate that CSR activity has a negative impact on the market value of the firm for the concurrent period, but from one-period time lag and afterwards CSR activity has a strong positive impact on the market value and sustains its positive impact on the market value even for a two-period time lag. The findings suggest that the economic effect of CSR activity on the firm market value tends to take some degree of lagged effects to be fully showcased in the market capitalization of tour operators and travel companies listed on Chinese stock markets. The findings suggest that, though CSR activity may carry some financial risk for an immediate short-term, tour operators must put a lot of time and effort into making CSR actions effective.

• Journal of Trauma and Injury
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• 제35권3호
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• pp.151-158
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• 2022

Purpose: There is a strong correlation between trauma and pain. Pain increases the rate of depression, posttraumatic stress disorder, and even mortality in trauma patients. Methods: This institution-based, provider-blinded and patient-blinded, observational study was conducted among trauma patients treated at Tikur Anbessa Specialized Hospital. Over the course of 3 months, this study included patients who had no prior pain management at other hospitals before presentation, and who presented within 24 hours of the traumatic event. Results: Of the 74 patients evaluated, none of the patients had their pain level scored. The researcher-provided pain scale showed a severe subjective pain score for 79.7% of the patients and a severe functional activity score for 59.5% of the patients. Analgesia was provided at an average of 55.4 minutes after presentation and all patients received either diclofenac or tramadol. Satisfactory pain reduction after analgesia was 28.8% for patients initially complaining of severe pain, 54.6% for moderate pain, and 66.7% for mild pain, with the difference being statistically significant (P<0.05). Forty percent of patients discharged home received no analgesia after the first dose provided upon presentation. Conclusions: Pain scoring was nonexistent during the course of the study. The poor utilization rate of analgesia combination and opioids led to unsatisfactory pain outcomes in patients evaluated and followed for 24 hours after presentation.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.47-51
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• 2013

Background: Postoperative complications after esophagectomy can lead to considerable patient discomfort and prolonged length of hospital stay. Lack of physical activity can be one of the independent risk factors for postoperative complications because physical activity is closely related to physical function. The objective of this study was to determine whether physical activity among esophageal cancer patients decreases their risk of postoperative complications after esophagectomy. Materials and Methods: We investigated 51 consecutive patients with newly diagnosed resectable esophageal cancer who were scheduled to receive esophagectomy between January 2009 and November 2011. Demographic, clinicopathologic, and treatment information were recorded and physical function was measured. The last 7-days short version of the International Physical Activity Questionnaire was used to assess physical activity before the operation. Stepwise multiple logistic regression analysis was used to determine whether preoperative physical activity is related to the risk of postoperative complications. Results: Male gender [OR 18.6, (95%CIs: 1.2-284.4); P=0.035], 3-field lymph node dissection (OR 9.6, [95%CIs: 1.4-66.6]; P=0.022), low-level physical activity (OR 28.3, [95%CIs: 3.5-227.7]; P=0.002), and preoperative comorbidities [OR 5.9, (95%CIs: 1.1-31.5); P=0.037] were found to be independently associated with postoperative complications. Conclusions: The present study shows that low-level physical activity, preoperative comorbidities, and 3-field lymph node dissection are independent and significant risk factors for postoperative complications after esophagectomy. Although further study is required, maintaining high-level physical activity preoperatively may decrease the risk of postoperative complications.

• 천문학회보
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• 제39권1호
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• pp.67.1-67.1
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• 2014

Comets are mysterious travelers from outer Solar System. It is considered that comets loose their subsurface ice once they were injected into a snow-line of the solar system, at the same time, develop adiathermic dust layers on the surface in a time scale of ~10,000 years. They eventually become inactive (see also the presentation by Yoonyoung Kim et al.). Optical similarity between comets and asteroids in comet-like orbits suggests the existence of such dormant or inactive comets supporting the evolutionary scenario. However, unforeseen accidents cast a misgiving to modify the stereotype. A periodic comet, 17P/Holmes, is known as comet with very low activity before 2007. However, the comet suddenly exhibited an outburst in 2007 October, which is known as the most energetic cometary outburst since the beginning of modern astronomy. On the other hand, another periodic comet, P/2010 V1, was not known before 2010 November probably because of low activity and discovered while it experienced outburst. We investigated the time-evolution of the magnitudes and the morphological developments based on the dynamical theory of dust grains, and derived the energy per unit mass of ~10,000 J/kg. From these observational evidences, we suggest that crystallization of buried amorphous ice (even in low-activity comets) can be responsible for the dramatic cometary outbursts.

• Safety and Health at Work
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• 제14권1호
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• pp.1-9
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• 2023

Background: Firefighting involves exposure of firefighters to risks related to this activity, serious injuries, and occupational diseases are recorded. There are other consequences such as thermal and emotional stress. This systematic review is proposed in order to analyze the risks and consequences faced by these workers and thus provide elements to improve safety management systems in institutions. Method: A descriptive observational study of systematic literature review on the risks and consequences of exposure to firefighters' activity was proposed, and the information was analyzed and described based on the available data and according to the variables determined. Results: The studies showed data on mechanical, physical, chemical, psychosocial risks, workers' perception and resilience, and epidemiological data. Information related to firefighters' activity on falls and slips, exposure to noise, and high concentrations of carbon monoxide is detailed. In addition, the relationship between burnout, cognitive, and physical fatigue as adverse effects on health and performance is mentioned. Conclusions: Among the preventive measures, the use of personal protective equipment is suggested, incorporation in prevention programs of information on exposure to risk factors, as well as the implementation of models that can predict the perception of workers, additionally, the generation of management systems with safety climate models for fire departments.

• 천문학회지
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• 제54권4호
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• pp.129-137
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• 2021

It has been established that the acoustic mode parameters of the Sun and Sun-like stars vary over activity cycles. Since the observed variations are not consistent with an activity-related origin, even Sun-like stars showing out-of-phase changes of mode frequencies and amplitudes need to be carefully studied using other observational quantities. In order to test whether the presumed relations between the global seismic parameters are a signature of the stellar activity cycle, we analyze the photometric light curve of HD 49933 for which the first direct detection of an asteroseismic signature for activity-induced variations in a Sun-like star was made, using observations by the CoRoT space telescope. We find that the amplitude of the envelope significantly anti-correlates with both the maximum frequency of the envelope and the width of the envelope unless superflare-like events completely contaminate the light curve. However, even though the photometric proxy for stellar magnetic activity appears to show relations with the global asteroseismic parameters, they are statistically insignificant. Therefore, we conclude that the global asteroseismic parameters can be utilized in cross-checking asteroseismic detections of activity-related variations in Sun-like stars, and that it is probably less secure and effective to construct a photometric magnetic activity proxy to indirectly correlate the global asteroseismic parameters. Finally, we seismically estimate the mass of HD 49933 based on our determination of the large separation of HD 49933 with evolutionary tracks computed by the MESA code and find a value of about 1.2M_☉ and a sub-solar metallicity of Z = 0.008, which agrees with the current consensus and with asteroseismic and non-asteroseismic data.