• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.868-870
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• 1999

A total of 69 ovaries were collected from 345 camels slaughtered in Maiduguri abattoir, North-Eastern part of Nigeria, to study the influence of season on ovary weight and corpus luteum count in the dromedary (single humped) camel (Camelus dromedaries). Right ovary was significantly heavier (p<0.01) and had more follicular fluid than the left. Although corpus luteum count increased gradually throughout the study period, no camel had 3 active corpora lutea and only 53 out of the total number had two. Ovarian activity seem to be higher in the cold dry harmattan season, November/December, than during the warmer post rainy season, September/October. These periods can be exploited by farmers, especially peasants who rely heavily on natural mating, to obtain greater conception rates and reduce the chance of failure during mating.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.143-153
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• 2008

The purpose of this paper is to evaluate impacts of ENSO on frequency and spatial distribution of rainfall in South Korea. In this paper, First, rainfall data in 60 climate stations were categorized into Warm(El Nino), Cold(La Nina), Normal episodes based on the Cold & Warm Episodes by Season, then 100 years of daily rainfall data were generated for each episodic events(El Nino, La Nina, Normal) using Markov Chain model. Finally, Estimating frequency based flood and comparison for each episodes were conducted. From the results, it shows that there are significant changes in the rainfall frequency and the spatial distribution of rainfall among Warm(EL Nino), Cold(La Nina) and Normal episodes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.69 no.2
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• pp.71-77
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• 2024

After the strongest El Niño since 2015 occurred in 2023, there has been a growing interest in understanding its impacts on rice yield in South Korea. We investigated the impact of El Niño during the rice-growing season on rice yield by analyzing the correlation between detrended rice yield data and ONI (Oceanic Niño Index) values exceeding 0.5. The results show a positive correlation between ONI intensities and detrended rice yields. Furthermore, we found that variations in sunshine duration, precipitation, and typhoon activity affect detrended yield values positively and negatively. This pattern was similar to the classification of El Niño into Cold Tongue El Niño and non-Cold Tongue El Niño, which showed positive and negative detrended rice yield values, respectively. This observation suggests that predicting yield based on ONI intensity during Cold Tongue El Niño years may be feasible to some extent.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.13-13
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• 2022

Recently, stable crop production is threatened by the effects of climate change. In particular, it is difficult to consistently maintain agricultural policies due to large price fluctuations depending on the difference in total domestic rice production from year to year. For stable rice production amid changes in the crop growing environment, development of varieties with improved disease resistance and abiotic stress stability is becoming more important. In here, drought and cold tolerant trait have been studied. First, for the development of drought tolerant varieties, we analyzed which agricultural traits are mainly affected by domestic drought conditions. As a result, it was observed that drought caused by the lack of water during transplanting season inhibits the development of the number of tiller and reduces the yield. 'Samgang' was selected as a useful genetic resource with strong drought tolerant and stable tiller number development even under drought conditions by phenotype screening. Three of drought tolerant QTLs were identified using doubled haploid (DH) population derived from a cross between Nacdong and Samgang, a drought sensitive and a tolerant, respectively. Among these QTLs, when qVDT2 and qVDTl1 were integrated, it was investigated that the tiller number development was relatively stable in the rainfed paddy field conditions. It is known that the high-yielding Tongil-type cultivars are severely affected by cold stress throughout the entire growth stage. In this study, we established conditions that can test the cold tolerance phenotype with alternate temperature to treat low temperatures in indoor growth conditions similar to those in field conditions at seedling stage. Three cold tolerant QTLs were explored using population derived from a cross between Hanareum2 (cold sensitive variety, Tongil-type) and Unkwang (cold tolerant variety, Japonica). Among these QTLs, qSCT12 showed strong cold tolerant phenotype, and when all of three QTLs were integrated, it was investigated that cold tolerant score was relatively similar to its donor parent, Unkwang, in our experimental conditions. We are performing that development of new variety with improved cold tolerant through the introduction of these QTLs.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.7
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• pp.1050-1056
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• 2014

This study investigated the main factors influencing digester temperature and methods to reduce heat losses during the cold season in the subtropics. Four composite digesters (two insulated and two uninsulated) were buried underground to measure their internal temperature ($^{\circ}C$) at a depth of 140 cm and 180 cm, biogas production and methane ($CH_4$) concentration in biogas from August to February. In parallel the temperature of the air (100 cm above ground), in the slurry mixing tank and in the soil (10, 100, 140, and 180 cm depth) was measured by thermocouple. The influent amount was measured daily and the influent chemical composition was measured monthly during the whole experimental period. Seasonal variations in air temperature significantly affected the temperature in the soil, mixing tank and digester. Consequently, biogas production, which is temperature dependent, was influenced by the season. The main factors determining the internal temperature in the digesters were insulation with Styrofoam, air temperature and temperature of slurry in the mixing tank. Biogas production is low due to the cold climate conditions in winter in Northern Vietnam, but the study proved that storing slurry in the mixing tank until its temperature peak at around 14:00 h will increase the temperature in the digester and thus increase potential biogas production. Algorithms are provided linking digester temperature to the temperature of slurry in the mixing tank.

• Tribology and Lubricants
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• v.36 no.6
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• pp.385-390
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• 2020

It rains heavily, such as long rain and typhoons, during a typical rainy season in Korea. In this season, several fuel contamination accidents by water and vehicular problems caused by water contaminated fuel occur. Many research groups have studied the effects of water contaminated fuel on vehicles and environment. However the characteristics of water contaminated fuel have not been studied. In this study, we prepared diesel samples with a constant ratio of water (0~30 volume %) using an emulsifier. Then, we analyzed these diesel samples for their representative fuel properties. In the analytical results, diesel with 30% water showed an increase in fuel properties such as density (823→883 kg/㎥), kinematic viscosity (2.601→6.345 ㎟/s), flash point (47→56℃), pour point (-22→2℃), CFPP (cold filter plugging point) (-17→20℃) and copper corrosion number (1a→2a). The low temperature characteristics, such as low pour point and CFPP, blocks the fuel filter in the cold season. In addition, water contaminated diesel decreases lubricity (190→410 ㎛) under high frequency reciprocating rig (HFRR) and derived cetane number (54.81→34.25). The low lubricity of fuel causes vehicle problem such as pump and injector damage owing to severe friction. In addition, the low cetane diesel fuel increases exhaust gases such as NOx and particulate matters (PM) owing to incomplete combustion. This study can be used to identify the problems caused by water contamination to vehicle and fuel facilities.

• Journal of Korean Medical classics
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• v.30 no.3
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• pp.95-108
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• 2017

Objectives : The concept of hidden Yin in summer by Zhu Danxi deals with the relationship between summer heat disease and hidden yin inside of human body. This paper attempts to ponder upon the clinical issues around which the discussions regarding the topic unfolded, and upon the texts on which the doctors of the discussions based their opinions. Methods : First, Danxi's argument as discussed in $G{\acute{e}}zh{\grave{i}}y{\acute{u}}l{\grave{u}}n$ is analyzed to find out his understandings of clinical issues and his textual sources on which he based his new perspective. Moreover, the prescriptions that Danxi thought was problematic and the concept of hidden yin as it existed before the time of Danxi are reviewed, and these findings are used understand Zhangjingyue's ground of criticism against Danxi. Lastly, this paper contemplates how these opposing opinions may be helpful to the general principles of medical theories. Results & Conclusions : There was a trend before the time of Danxi of abusing drugs as prescription based on warm-heat, understanding that a human body has yin-cold during summer. However, Danxi brought forth a new concept of yin deficiency in order to correct people's misunderstanding. Despite his effort, Zhangjingyue and other doctors contemporary to Danxi emphasized on one hand that human body is placed on a state of external heat inside the cold, and on the another, criticized Danxi of failing to fully understand the principle of "Abandon the time and follow the symptoms", a principle which asserts that the cold and warm of medicine should be decided by the symptom itself and not by the season. The value of these contradicting assertions seems to hold true even to this day because it helps us understand that the principles of "Counting Season as a Treatment Factor" and "Abandon the time and follow the symptoms" could be applied with balance in conjunction with each other.

• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.64-74
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• 2024

This pilot study aimed to investigate the effects of regional and seasonal variations on the prevalence of Theileria orientalis and the hematological profile of non-grazed dairy cows in Korea. A total of 365 clinically healthy lactating Holstein Friesian cows from 26 dairy farms in 7 provinces that were categorized into northern, central, and southern regions were sampled during the warm period from July to August and the cold period from October to December. The detection of T. orientalis major piroplasm surface protein gene and the hematology non-grazed dairy cows were analyzed using peripheral blood samples. The T. orientalis prevalence was 20.0% (73/365). The prevalence in the southern region was 35.9%, which was significantly higher than that in the central (21.6%) and northern (12.9%) regions (P<0.05). The prevalence during warm period was higher (43.0%) than that during the cold season (13.5%). The infected cows showed significantly lower erythrocyte counts in the southern region (5.8±0.6 M/㎕) and during the warm period (5.8±0.7 M/㎕) compared with those in the central and northern regions and during the cold season, which affected the extended RBC parameters, including hematocrit and hemoglobin concentrations. Our findings revealed the prevalence of T. orientalis in Korea, highlighting its high occurrence during warm periods and in certain geographical regions. Climatic factors could contribute to the health and productivity of cattle, as evidenced by the prevalence of T. orientalis and its negative impact on animals.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.11 no.2
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• pp.49-54
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• 1978

The cold water mass appeared in offshore of the east coast of Korea in summer season was studied in aspect of chemical oceanography. Such a typical relationship between phosphate and dissolved oxygen as shown in the upwelling regions could not be found in the east coast except around the Kampo coast, southern part of the east coast. It is possible to isolate the North Korean Cold Water from tile proper water of tile Japan Sea by using $\sigma_t-O_2$ diagram. The origin of the cold water mass in offshore of the east coast of Korea in summer is not mainly due to the development of upwelling of the proper water of the Japan Sea but thesouthwardflolvingoftheNorthKoreanCold Water.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.1
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• pp.51-59
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• 2012

The cold weather concrete poured in the winter season can cause the problem of the Due to recent high-rise building is made. In this research, the nominal mix of the early strength in concrete tried to be set through the mixing proportion experiment for each empirical variable and each component strength properties for the early strength improvement tries to be examined. In the cold weather concrete experiment, the cement and high early strength (type3) cement improving in OPC than OPC was excellent. The polycarboxylic acid based compound was exposed to be excellent in the intensity revelation properties. Because the using of the fly ash was disadvantageous it was excluded from this experiment. It showed the optimum temperature for the intensity revelation up over $12^{\circ}C$.