• Asian-Australasian Journal of Animal Sciences
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• 제28권7호
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• pp.943-950
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• 2015

Heat stress has adverse effects on fertility of dairy animals. Decline in fertility is linearly associated with an increase in combination of both temperature and humidity. The purpose of this study was to investigate the relationship between temperature humidity index (THI) and the pregnancy rate of Murrah buffaloes in a subtropical climate. The effects of genetic and non-genetic factors viz., sire, parity, period of calving and age group at first calving were found non-significant on pregnancy rate. The effect of THI was found significant (p<0.001) on pregnancy rate of Murrah buffaloes calved for first time and overall pregnancy rate. The threshold THI affecting the pregnancy rate was identified as THI 75. The months from October to March showed THI<75 and considered as non heat stress zone (NHSZ), while months from April to September were determined as heat stress zone (HSZ) with $THI{\geq}75$. The lowest overall pregnancy rate (0.25) was obtained in July with THI 80.9, while the highest overall pregnancy rate (0.59) was found in November with THI 66.1. May and June were identified as critical heat stress zone (CHSZ) within the HSZ with maximum decline (-7%) in pregnancy rate with per unit increase in THI. The highest overall pregnancy rate was estimated as 0.45 in NHSZ with THI value 56.7 to 73.2. The pregnancy rate was found to have declined to 0.28 in HSZ with THI 73.5 to 83.7. However, the lowest pregnancy rate was estimated as 0.27 in CHSZ with THI value 80.3 to 81.6.

• 한국환경과학회지
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• 제29권7호
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• pp.785-788
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• 2020

We investigated the oviposition characteristics of Protaetia brevitarsis seulensis, focusing on zone breeding throughout the year in terms of the development and utilization of insect resources. To select Protaetia brevitarsis seulensis individuals laying a large number of eggs, the number of eggs laid for each individual was measured for each individual after emergence as adults from larvae grown at room temperature in five farmhouses. The five study zone included Gongju (Tancheon), Gyeonggi (Himsen), Chungnam (Gyeryong), Taean (Wonbuk), and Siheung (Baekse). The average oviposition tendency during a 12-week period obtained from the five regions was somewhat different; however, there was no remarkable difference in overall tendency. The maximum oviposition in Protaetia brevitarsisseulensis in the five regions occurred between 6 and 7 weeks. Compared toother regions, the average cumulative number of eggs laid during the 12-week period was higher (40%-60%) in Gongju (Tancheon) and Gyeonggi (Himsen). These results indicate that in two regions, zone breeding is selected as a system for increasing the demand for insects.

• Geomechanics and Engineering
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• 제38권3호
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• pp.215-229
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• 2024

Because of the various patterns of deep-water inrush and complicated mechanisms, accurately predicting mine water inflows is always a difficult problem for coal mine geologists. In study presented in this paper, the water inrush channels were divided into four basic water diversion structures: aquifer, rock fracture zone, fracture zone and goaf. The fluid flow characteristics in each water-conducting structure were investigated by laboratory tests, and multistructure and multisystem coupling flow analysis models of different water-conducting structures were established to describe the entire water inrush process. Based on the research of the water inrush flow paths, the analysis model of different water inrush space structures was established and applied to the prediction of mine water inrush inflow. The results prove that the conduction sequence of different water-conducting structures and the changing rule of permeability caused by stress changes before and after the peak have important influences on the characteristics of mine water-gushing. Influenced by the differences in geological structure and combined with rock mass RQD and fault conductivity characteristics and other mine exploration data, the prediction of mine water inflow can be realized accurately. Taking the water transmitting path in the multistructure as the research object of water inrush, breaking through the limitation of traditional stratigraphic structure division, the prediction of water inflow and the estimation of potentially flooded area was realized, and water bursting intensity was predicted. It is of great significance in making reasonable emergency plans.

• 한국환경과학회지
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• 제29권9호
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• pp.935-938
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• 2020

This study investigated the oviposition characteristics of Protaetia brevitarsis seulensis after emergence as adults from the larva collected from three regions in Gangwon-do, Chungcheongnam-do, and Jeju-do. The laying egg method was identified with zone breeding, and the average and cumulative number of eggs laid were measured once a week for seven weeks. The average number of eggs laid peaked until 4 weeks, and subsequently decreased. The source areas with respect to average number and cumulative number of eggs laid were in the order of Jeju > Chungnam > Gangwon. In conclusion, this result suggests a method for continuously improving management and economic feasibility of insect farming by securing genetic diversity, and raising the most productive breeds to select individuals form regions associated with high numbers of laid eggs.

• ALGAE
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• 제38권2호
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• pp.141-150
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• 2023

Light quality is a common environmental factor which influences the metabolism of biochemical substances in algae and leads to the response of algal growth and development. Pyropia yezoensis is a kind of economic macroalgae that naturally grows in the intertidal zone where the light environment changes dramatically. In the present study, P. yezoensis thalli were treated under white light (control) and monochromatic lights with primary colors (blue, green, and red) for 14 days to explore their physiological response to light quality. During the first 3 days of treatment, P. yezoensis grew faster under blue light than other light qualities. In the next 11 days, it showed better adaptation to green light, with higher growth rate and photosynthetic capacity (reflected by a higher rETR_max = 61.58 and E_k = 237.78). A higher non-photochemical quenching was observed in the treatment of red light than others for 14 days. Furthermore, the response of P. yezoensis to light quality also results in the difference of photosynthetic pigment contents. The monochromatic light could reduce the synthesis of all pigments, but the reduction degree was different, which may relate to the spectral absorption characteristics of pigments. It was speculated that P. yezoensis adapted to a specific or changing light environments by regulating the synthesis of pigments to achieve the best use of light energy in photosynthesis and premium growth and metabolism.

• 한국산림과학회지
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• 제88권3호
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• pp.379-388
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• 1999

우리 나라에 적용할 산림용 종자 산지구분(塵地區分)의 첫 단계로 임목집단의 유전생태적 분화에 영향이 큰 연평균 온도, 극한 최저온도, 생육기간중 상대습도, 일조량, 건조지수 등 기상인자를 척도로 수평적 산지를 구분하였다. 적용한 산지구분의 개념은 전형적인 산지구분 형태인 수종별 구분법보다는 전 수종을 포함한 생태지역 개념의 산지구분법에 따랐다. 산림대를 대구분 단위로 하여 산림대별(난대, 온대남부, 온대중부, 온대북부)로 기본구역을 설정하여 유집분석을 근거로 난대 3, 온대남부 6, 온대중부 8, 온대북부 2로 총 19개의 수평적 산지로 구분하였다. 적용한 6개의 척도중 연평균 온도, 극한 최저온도, 생장일수는 산림대별로 난대에서 온대북부 방향으로 일정한 경향을 보였으며 상대습도, 일조량 및 건조지수에서는 일정한 경향을 보이지는 않았으나 산지간에는 많은 차이를 보여 이들 인자는 미세 환경인자에 민감한 것으로 나타났다. 본 연구에 의해 구분된 산지는 구획 초기단계로 잠정적인 산지로 활용하면서 금후 생물기후도, 산지시험, 유전생태 자료 등이 축적되면 보완해 나갈 것이다.

• 한국가축번식학회지
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• 제12권3호
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• pp.148-155
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• 1988

Holstein cows being raised in the Kangweon district were examined on the breeding status and occurrence of reproductive disorder. The results obtained were as follows; 1. The cows above six years old in the alpine area were raised more than those in high level zone and plate zone. 2. A total of 1,350 Holstein cows were examined on the breeding status. They were 71.9% conceived cows, 7.9% of uncertain1$\frac{1}{2}$ regnancy, 7.0 of physiological vacancy and 13.3 of reproductive disorder. 3. The percentage of cows conceived by 1, 2, 3 and more than 4 times of A.I. was 49.9, 29.2, 13.3 and 7.6, respectively. 4. In the nutritional condition of infertile coes, excellent, good, fair and poor were 6.7, 30.2, 34.1 and 29.1, respectively. In the good and fair nutritional condition, the cows of ovarian syndrome were 15.6% of persistent corpus luteum, and 11.7% of follicular cystic ovary and lutein cystic ovary, respectively. 5. Among 179 inferTile cows, distributions of reproductive disorder were 43.0, 39.1, 3.9, 3.9 and 10.1% in ovary, uterus vagina, oviduct and others, respectively. Ovary showed higher percentage than any other reproductive organs. Among the ovarian syndromes, follicular cystic ovary, lutein cystic ovary and persistent corpus luteum were 28.6, 28.6 and 23.4%, respectively. 6. A cow group of six and seven-year old showed the highest percentage(21.0% and 23.3%) among the age groups in infertile cows. In the syndrome of reproductive disorder, catarrhal endometritis, latent endometritis, follicular cystic ovary and lutein cystic ovary were 14.5, 14.0, 12.3 and 12.3%, respectively. 7. Infertile cows with complex syndrome of genital disease was 31.8%.

• 한국농림기상학회지
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• 제18권4호
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• pp.274-286
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• 2016

전체 온실가스 배출량의 약 72%를 차지하는 이산화탄소($CO_2$)는 지구온난화를 야기하는 대표적인 온실가스로 분류되어 있다. IPCC의 제5차 기후변화 종합평가보고서(2014)에 의하면, 지난 100년간 지구 대기의 $CO_2$는 약 35% 증가했으며 지구의 온난화는 최근 30년간 심화되는 것으로 나타났다. 이에 따라 지구 온난화에 따른 기후변화, 기상이변으로 산림식생대의 이동과 식물계절 변화가 유발되고 있다. 산림은 교토의정서에서 인정한 유일한 온실가스 흡수원으로서 보전 및 증진 필요성이 있으며 기후변화에 대한 수목 반응의 연구는 미래의 산림생태계 변화를 예측하는데 필수불가결한 요소이다. 따라서 장기 기후변화 연구시설을 이용한 수목의 생리 생태적 반응 연구와 실제 산지에서 이루어지는 장기 모니터링 연구를 결부하여 이용한다면 기후변화로 인한 미래 산림생태계의 변화를 예측하고 대응하는데 크게 기여할 것이다.

• 한국작물학회지
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• 제44권3호
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• pp.207-213
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• 1999

Thirty-eight glutinous rice varieties were classified into nine groups on the scatter diagram by the upper two principal components (56% contribution to the total information) based on eleven physicochemical characteristics including the viscograms and physical properties of cooked rice. The first principal component was the factor mainly associated with the viscogram characteristics of rice flour emulsion and the second was the factor chiefly related to the physical properties of cooked rice and water absorbability of rice grain. Indica glutinous rices were clearly distinguished from japonica ones by the first principal component score. Javanica glutinous rices were widely distributed on the intermediate zone between indica and japonica or on several japonica rice groups. Significant positive or negative correlations were found among water absorption rates of rice grain, physical properties of cooked rice, and viscogram characteristics of rice flour. Especially in japonica glutinous rices, the breakdown and setback viscosities of rice flour were closely associated with the alkali digestion value of milled rice and the stickiness of cooked rice. The frequency ratio of short glucose chains (A-chain) to intermediate glucose chains (B-chain), the ratio of B- chains to long glucose chains (C-chain) and the relative frequency of A- or B-chain fractions representing the amylopection structure of rice starch was closely associated with the breakdown and setback viscosities of rice flour.

• Asian-Australasian Journal of Animal Sciences
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• 제4권4호
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• pp.333-339
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• 1991

Eighty-two ewes of Balochi breed, two to four years of age were used in a completely randomized design to study the effect of winter supplementation on their performance in Kalat area of Balochistan and randomly divided into two groups of 40 and 42 animals. Two treatments (T1 and T2) studied were : 250 gm/animal/day of a 50 : 50 mixture of cottonseed cake and barley grain fed from Oct. 20 to Dec. 18, 1988 plus grazing and 500 gm/animal/day of the same feed mixture fed from Oct. 9 to Dec. 18, 1988 in addition to grazing. Lucerne hay and wheat straw in a 50 : 50 ratio were provided to all the ewes for a period of one month from Jan. 6, 1989 @ 320 gm/animal/day to sustain them in severe winter. Same feeding levels to the same ewe groups were again fed from Mar. 1 to May 27, 1989. Three breeding rams stayed with the flock from Nov. 1 to Dec. 13, 1988. Lambing took place from Apr. 2 to May 12, 1989. Conception, lambing and mortality percentage was found different (P<.05) between T1 and T2 (12.5 vs 14.8 kg). The ewes on T2 maintained higher body weights throughout winter than the ewes on T1. The results are suggestive of improvement in conception rate with winter supplementation (flushing) and decrease in ewe mortality. Late-gestation and early-lactation supplemental feeding of ewes results in increases in weaning weights of their lambs.