• Research in Community and Public Health Nursing
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• v.15 no.2
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• pp.289-297
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• 2004

Purpose: This study was conducted to determine factors affecting workers' physiological somatic complain using the Job Stress Model proposed by the National Institute for Occupational Safety and Health (NIOSH). Method: Data were collected from the 1st to the 30th of December 1999. The subjects were 2.123 workers employed at 155 work sites. Collected date were analyzed through SAS/PC program. Result: According to individual characteristics, younger and women groups showed significantly higher physiological somatic complaint than elder men groups. By work condition, groups with higher physiological somatic complaint included workers of irregular shift work. Dark lighting, improper temperature in winter, improper ventilation, inappropriate humidity, unpleasant work environment and crowded work place were significantly related with physiological somatic complaint. By work-related factor, physiological somatic complaint was high in those with higher variance in work load, quantitative work load, role conflict, job burden, role ambiguity and future ambiguity. On the other hand, physiological somatic complaint was low in those with little underutilization of ability. As for the relationships between physiological somatic complaint and non-work related factors, physiological somatic complaint was high in workers who had a side job, were bringing up infants alone, cleaned the house alone, cared for the elderly and disabled persons, were studying, were volunteering at another organization, and were spending 5-10 hours in religious activities per week. Physiological somatic complain was in significantly negative correlations with overall social support, supervisory support and family support, but in significantly positive correlations with co-worker support. Conclusion: The main predictors of physiological somatic complain were gender, shift work pattern, overtime work, ventilation, role ambiguity, role conflict, future ambiguity, job control, variance in work load, overall social support, worker with side job, worker who cleans the house alone, worker who is studying. These predictors explained 19.10% of the total variance of physiological somatic complain.

• Journal of the Korean GEO-environmental Society
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• v.11 no.12
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• pp.5-11
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• 2010

If the groundwater in rock joint is changed into ice, it induces the stress increment by volume increase. Also, if the ice is changed into groundwater again, the stress in joint decreases by volume decrease. The accumulated displacement and fatigues of joints are increased by the stress-hysterisis, induced from the continuous frost-thawing. Also the shear strength is decreased by them continuously. The stress-hysterisis is affected by the atmospheric temperature changes, whose behavior is visco-elasticity, usually. Therefore, Kelvin model could be used to analyze the frost-thawing behavior in winter. The measured data of total 5 points are examined, which are composed of 3 points of shallow joints and 2 points of deep joints. Because shallow weathered rocks have many joints, a lot of Kelvin model are connected and the behaviors are complicated. In case of deep joints, simple Kelvin model is applied and the behaviors are also simple.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.35 no.5
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• pp.463-468
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• 2002

Influence of increased temperature on the standard metabolism in three species of marine bivalves, Crassostrea gigas, Ruditapes philippinarum and Mytilus edulis, acclimated to seasonal water temperatures and collected from the south coast of Korea, were examined in the laboratory. The standard oxygen consumption and filtration rates in the 3 species were measured respectively at the experimental temperature, 4, 7 and 10$^{\circ}C$ or 3, 6 and 9$^{\circ}C$ higher than the mean seasonal water temperature. When the experimental temperatures were higher than the seasonal water temperature, the rates of C. gigas decreased in autumn and spring, and increased In winter, while there was thermal stress in summer. The rates of R. philippinarum increased in spring when the experimental temperatures were 3$^{\circ}C$ and 6$^{\circ}C$ higher than the seasonal water temperature, but the rates increased in autumn and winter when the experimental temperature was even 9$^{\circ}C$ higher than the seasonal water temperature. In summer. metabolic activities of R. philippinarum decreased significantly at temperature higher than acclimation temperature. The rates of M. edulis increased in spring when the experimental temperatures were 3$^{\circ}C$ higher than the seasonal water temperature but the rates were stressed by the increased temperature above 3$^{\circ}C$. In winter, increased temperature did not affect the metabolic activities of M. edulis. These results suggested that the standard metabolism of the three marine bivalves in summer was stressed by the increased temperature, whereas the metabolism was activated in winter.

• Ocean and Polar Research
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• v.34 no.4
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• pp.403-411
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• 2012

Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.

• Journal of the Korean Society of Safety
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• v.34 no.2
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• pp.34-39
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• 2019

Vinyl house consists of main rafter, lateral member, clamps and polyethylene film. Many vinyl houses are used in the countryside to grow vegetables. These vinyl houses have occasionally been collapsed due to heavy snowfall in winter. Many farmers get a lot of economical damages, if vinyl houses are collapsed. So it is most important to built a safe vinyl house that can withstand heavy snowfall. In this study, a structural analysis was performed on three types of vinyl houses(07-single-01, 10-single-04, 12-single-01). In addition, the structural analysis of the three types of vinyl houses provided axial forces, flexural moment, and combined stress. For these three types of vinyl houses, structural safety was reviewed by obtaining the combined stress ratio by the strength design method. This structural review showed that the specifications for the vinyl house proposed in the design are not safe. Especially, the result of increasing the design snow load by 15 percent and 30 percent showed that the vinyl house structure constructed as a standard for vinyl house was a more dangerous structure. Therefore, it is necessary to revise regulations such as increasing the thickness of rafters or widening the gap in order to make vinyl houses structurally safe for heavy snowfall in the future, and to devise diverse methods to make vinyl houses that are structurally safe.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.66 no.1
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• pp.37-71
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• 2021

Rapeseed is a typical winter crop, and its freezing stress tolerance is a major feature for winter survival. Therefore, it is important to comprehend clearly the physical and molecular mechanisms of rapeseed under freezing stress conditions. This study investigates the physical and transcriptome changes of two rapeseed lines, 'J8634-B-30' and 'EMS26', under cold acclimation and freezing temperature treatments. The proline content of 'J8634-B-30' at 5 ℃ increased 8.7-fold compared to that before treatment, and there was no significant change in that of 'EMS26' RNA-sequencing analysis revealed 5,083 differentially expressed genes (DEGs) of 'J8634-B-30' under cold acclimation condition. Among the genes, 2,784 (54.8%) were up-regulated and 2,299 (45.2%) were down-regulated. The DEGs of 'EMS26' under cold acclimation condition were 5,831 genes, and contained 2,199 up-regulated genes (37.7%) and 3,632 down-regulated genes (62.3%). Among them, only DEGs annotated in the cold response-related signaling pathways were selected, and their expression in the two rapeseed lines was compared. Comparative DEGs analysis indicated that cold response related signaling pathways are proline metabolism and ABA (Abscisic acid) signaling. And ICE (Inducer of CBF expression) - CBF (C-repeat-binding factor) - COR (Cold-regulated) signaling were the significantly differentially expressed transcripts in the two rapeseed lines. The major induced transcripts of 'J8634-B-30' induced P5CS (Δ'-pyrroline-5-carboxylate synthetase), which is related to proline biosynthesis, PYL (pyrabactin resistance-like protein, ABA receptor) and COR413 (cold-regulated 413 plasma membrane 1). In conclusion, these result provide a foundation for understanding the mechanisms of freezing stress tolerance in rapeseeds. Further functional studies should be performed on the freezing stress-related genes identified in this study, which can contribute to the transgenic and molecular breeding for freezing stress tolerance in rapeseed.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.2
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• pp.189-195
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• 1997

To cope with increasing importance of water stress in food crop production, characteristics and cultivar differences in physiological responses of winter barley plants to water stress during seedling stage were studied employing three covered-barley, Milyang 12, Durubori, and Olbori, one naked-barley, Baekdong, and one two-row beer-barley, Hyangmaeg. Water stress was given to barley plants by withholding watering in soil-culture pots or by adding P.E.G. (polyethylene glycol, M. W. 4,000) to the nutrient culture solution. When water stress was imposed by withholding watering for 10 days to the seedlings grown in pot-soil for 10 days after emergence, leaf water potential of 5 cultivars was decreased almost to the same degree, from control -3.5 bar to the water stressed -26.6 bar. However, growth and some physiological responses were differently affected by cultivars: The plant height was decreased by 16-26％ : seedling dry weight by 25∼42％ ; chlorophyll content by 21∼39％ ; second leaf survival rate by 8∼18％ ; and free proline content per gram of leaf dry weight was increased from control 0.2∼0.5mg to the water stressed 5.8∼13.2mg. Drought resistances of 5 barley cultivars, based on the leaf survival rate and the decreased rate in seedling dry weight at the end of stress treatment, were high in the order of 3 covered-barley＞naked-barley＞two-row barley.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.1659-1663
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• 2011

Precast concrete slab track is a track structure to be installed by transporting and assembling precast concrete slabs manufactured at the factory. This method can improve concrete quality, provide easy maintenance and reduce construction time, compared with in-situ concrete track. However, the concrete slabs being continuously connected in longitudinal direction, due to the temperature change between summer and winter, the openings at slab joints have occurred. Thus, in this study, to identify the cause of this opening of slab joint, the joint opening caused by temperature drop in the longitudinally continuous precast concrete slab track has been predicted using three-dimensional finite element analysis, and compared with field measurements. Based on the proven model, the slab joint opening, and the stress pattern of concrete slab and steel reinforcement according to concrete slab-base friction properties, concrete-reinforcement bond properties, and prestressing were analyzed.

• Journal of fish pathology
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• v.15 no.1
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• pp.43-48
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• 2002

A blood biochemical analysis was carried out for the serum of wintering sea bream (red sea bream Pagrus major, black sea bream Acanthopagrus schlegeli, rock bream Oplegenathus fasciantuas) with green liver syndrome. GOT and GPT were significantaly elavated in the diseased sea bream. The value of $NH_{3}$ was slightly higher but those of TBIL. TP and UA were lower than the control. But there were no differences in albumin. Ca and glucose between the diseased and the control. These results suggent that a green liver syndrome in the sea bream might be related with nutritional defects and the stress of low water temperature during the winter.

• Proceedings of KOSOMES biannual meeting
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• 2001.10a
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• pp.137-144
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• 2001

A Plankton ecosystem model was developed to investigate effects of hydrodynamic processes including advection and diffusion on size-structured phytoplankton dynamics in the mesohaline zone of the York River estuarine system, Virginia, USA. The model included 12 state variables representing the distribution of carbon and nutrients in the surface mixed layer. Groupings of autotrophs and heterotrophs were based on cell site and ecological hierarchy Forcing functions included incident radiation, temperature, wind stress, mean How and tide which includes advective transport and turbulent mixing. The ecosystem model was developed in FORTRAN using differential equations that were solved using the 4th order Runge-Kutta technique. The model showed that microphytoplankton blooms during winter-spring resulted from a combination of vertical advection and diffusion of phytoplankton cells rather than in-situ production in the lower York River estuary.