• Journal of Plant Biology
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• v.28 no.2
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• pp.149-164
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• 1985

Intertidal algal community of Muchangpo in western coast of Korea was investigated qualitatively and quantitatively. Seasonal changes of algal occurrence, dominant species in cover, vertical zonation pattern and biomass were analysed. A total of sixty-four species of marine algae, one blue-green alga, three green algae, nineteen brown algae and forty-one red algae, were identified. The dominant species in cover were Sargassum thunbergii, Gelidium divaricatum and Pelvetia siliquosa throughout the year. Gloiopeltis furcata was abundant at upper and middle littoral zones and Corallina pilulifera at lower littoral zone. Classification by unweighted pair-group average method and ordination by reciprocal averaging based on the cover data indicated that, on the whole, the intertidal algal vegetation showed different patterns along tidal levels. Seasonal fluctuations of mean biomass were 57.2~92.8 g-dry/$m^2$, and the highest in summer and the lowest in spring season. Seasonal change of community structure was also discussed.

• Korean journal of applied entomology
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• v.29 no.4
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• pp.230-237
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• 1990

Studies were carried out to examine seasonal occurrence and emergence pattern of the onion fly, Delia antiqua (Meigen), in the field of Chinju city in Gyeongnam province from 1984 to 1987. Trap catch revealed that the onion fly had three generations in a year, the second flight being partial; the peaks of adult occurrence were at mid April for the overwintered generation (1st flight), at early June for the first generation (2nd flight), and at the period from late September to early October for the autumn generation (3rd flight). It was shown that parts of the pupae in the first and almost all of the pupae in the second (or autumn) generation underwent summer diapause. The pupal periods were less than 22.4 days for the non-diapaused pupae, while those of the diapause. The pupal periods were less than 22.4 days for the non-diapaused pupae, while those of the diapaused pupae were form 8.5 to 145 days in the first generation in he filed, being shorter for the pupae pupated later. This resutled in synchronization on the emergence of these diapaused pupae at late September, with the adults from the second generation pupae. The ratio of diapausing pupae increased among the later pupated ones in the first generation ; the pupae which had been pupated in early May included 43.8% of diapausing pupae, while more than 86.7% of the pupae were under diapausing state for the pupae pupated in late May and thereafter. More than 93.3% of the pupae went into diapause, regardless of pupation time for the second generation.

• The Korean Journal of Ecology
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• v.16 no.2
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• pp.209-227
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• 1993

Aquatic insects were collected from 18 sites in the Yongsan River System from August, 1988 to July, 1989. The monthly fluctuation and distributional pattern of the aquatic insects along the environmental factors were investigated. Quantitatively collected aquatic insects were identified, and numbers, standing biomass, dominance indices and diversity indices in each site and month were determined. The aquatic insect faun of the Yongsan River System was composed of 146 species, 82 genera, 38 families in 7 orders including 44 species of mayflies, 32 species of caddisflies, 24 species of stoneflies, 21 species of flies, 16 species of beetles, 6 species of dragonflies and 3 species of dobsonflies. Seasonal occurrence of species were more diversified in winter and spring than in summer. Also, the number of individuals occurred was higher in winter and spring than in summer while it was the highest in upper stream and the lowest in Kwang-ju stream. Component ratio of the number of individuals according to the insect orders was as follows: Mayflies 38.71%, Flies 36.97%, Stoneflies 10.21%, Caddisflies 6.80%, Beetles 2.96%, Dobbsonflies 2.74%, Dragonflies 0.95%. Percentage of standing biomass according to insect orders were as follows: Mayfiles 32.81%, Stoneflies 26.51%, Caddisflies 17.58%, Dobbsonflies 14.84%, Flies 3.74%, Beetles 3.08%, Dragonflies 1.45%, The highest standing biomass occurred in spring and the lowest in summer.

• Fisheries and Aquatic Sciences
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• v.1 no.1
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• pp.147-151
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• 1998

The reproductive phenology of Gracilaria verrucosa was studied in Cheongsapo near Pusan, Korea. Among the life history phases, tetrasporic plants occurred dominantly in varying degrees of abundance throughout the year except from July to September. Cystocarpic plants increased rapidly during summer, and then recorded maximum abundance in July. Whereas, seasonal peaks of spermatangial plants were observed in April and September. However, they were less than cystocarpic plants in abundance. Vegetative plants dominated from December to May for long period, with a occurrence peak in February. Even though fertile plants in both gametophytes and tetrasporophytes occurred throughout the year, their seasonal abundance suggests that the positive correlation between reproduction and water temperature is basically found in the reproductive pattern of Gracilaria verrucosa. The distributional aspect of life history phases appears to be related with differences of their longevity, fecundity or survivorship.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.1
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• pp.91-100
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• 2004

Energy efficiency evaluation method for a multi-type air conditioning system still has not been developed. In this study, analysis on capacity range and evaluating method of standards for air conditioners was conducted with world-wide Standards. It is not a proper approach to use the standards for residential air conditioner to multi type air conditioners. Some difficulties and problems are commented in this study with overview of the standards. Through the analytic research, an evaluating method for multi type air conditioner was suggested with Integrated Part Load Value (IPLV). The suggested concept for evaluating energy efficiency during part load condition considers building load pattern and operating hours of the system at different locations. Load was weighted in IPLV to consider not only the concept of occurrence of outdoor temperature such as bin method but also operation hours of the system. An experiment about the IPLV was conducted with variable air volume ducted type air conditioning system and multi-type system through modified code tester to give a glance at quantitative value of the IPLV.

• Asian Journal of Atmospheric Environment
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• v.9 no.1
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• pp.66-77
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• 2015

In order to survey the seasonal variation of the chemical composition of particulate matter of $2.5{\mu}m$ or less ($PM_{2.5}$), $PM_{2.5}$ was sampled from 8 February 2013 to 31 March 2014 in an industrial area of Chiba Prefecture, Japan. Chemical measurements of the sample included: ionic components ($Na^+$, $NH_4{^+}$, $Ca^{2+}$, $Mg^{2+}$, $K^+$, $Cl^-$, $NO_3{^-}$ and $SO_4{^{2-}}$), carbonaceous components - organic carbon (OC) and elemental carbon (EC), and water-soluble organic carbon (WSOC). Also, secondary organic carbon (SOC) was measured based using the EC tracer method, and char-EC and soot-EC were calculated from the analytical results. The data obtained were interpreted in terms of temporal variation. Of the overall mean value of $PM_{2.5}$ mass concentration obtained during the study period, ionic components, OC and EC accounted for 45.3%, 19.7%, and 8.0%, respectively. $NO_3{^-}$ showed a unique seasonal distribution pattern due to a dependence on temperature and absolute humidity. It was estimated that an approximate temperature of $14^{\circ}C$, and absolute humidity of $7g/m^3$ were critical for the reversible reaction of $NH_4NO_3(p){\leftrightharpoons}NH_3(g)+HNO_3(g)$. The amount of OC and EC contributing to the monthly $PM_{2.5}$ mass concentration was higher in autumn and winter compared to spring and summer. This result could be attributed to the impact of burning biomass, since WSOC and the ratio of char-EC/soot-EC showed a similar pattern during the corresponding period. From the comparison of monthly WSOC/OC values, a maximum ratio of 83% was obtained in August (summer). The WSOC and estimated SOC levels derived from the EC tracer method correlated (R=0.77) in summer. The high occurrence of WSOC during summer was mainly due to the formation of SOC by photochemical reactions. Through long-term observation of $PM_{2.5}$ chemical components, we established that the degree to which the above-mentioned factors influence $PM_{2.5}$ composition, fluctuates with seasonal changes.

• Korean journal of applied entomology
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• v.44 no.4 s.141
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• pp.337-339
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• 2005

In Iksan, Korea, Parnara guttata Brener et Grey spend three generations per year, 1st generation adult emerged mid to late May from pupa developed from overwintered larva in weeds on bank around rice paddy field or on hillside and moved to rice paddy field to lay eggs on leaves of rice. The damage to rice by 2nd generation larva began to increase late July and reached peak from mid to late August. The 3rd generation adults were observed early to mid September and flew away from rice paddy field. There was significant relationship between the transplanting time and the occurrence of P. guttata in rice paddy fields. P. guttata preferred the rice transplanted in late season in paddy field. Insecticide treatment on late July about a week before the peak larval occurrence reduced the damage by P. guttata up to 91.2%, whereas the treatment on early August was a lot less effective reducing only 57.2% of the damage.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.16 no.3
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• pp.162-170
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• 2013

Purpose: To detect major acute gastroenteritis virus (rotavirus, norovirus, astrovirus, and enteric adenovirus) and non-enteric type of adenovirus (AdV) in the stools of intussusception patients and to investigate the clinical role of detected viruses. Methods: From March 2012 to February 2013, major acute gastroenteritis virus and non-enteric type of AdV were isolated from stool samples that collected from 44 patients treated for intussusception in Chungnam National University Hospital. Patients were divided according to age and isolated virus. Results: Virus was detected in 28 (63%) stool specimens. The virus detection rate was significantly lower in patients aged under 12 months (p = 0.04). Twenty-two patients (78.6%) had non-enteric adenovirus, 4 (14.3%) had norovirus, 1 (3.6%) had sapovirus, and 1 (3.6%) had astrovirus. AdV subgroup C (AdV 1, 2, 5, and 6) comprised the majority with 20 cases (90.9%). A monthly increment-and-decrement pattern of intussusception was similar to that of viral detection in the stool samples. Enema reductions were successful in 39 patients and surgical manual reductions were performed in 5 patients. Virus was detected in 24 patients (61.5%) of enema reduction group and 4 patients (80.0%) of surgical manual reduction group. All of the detected viruses were non-enteric adenovirus subgroup C (AdV 1, 5, and 6) in surgical reduction patients. Conclusions: The virus detection rate was high in the stools of intussusception patients. The pattern of seasonal intussusception occurrence rate was parallel with seasonal these viral detection rate in the stool samples. These findings suggest that viral infection plays an important role in the development of intussusception and further research is warranted.

• Animal Systematics, Evolution and Diversity
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• v.31 no.4
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• pp.296-303
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• 2015

We surveyed moths on Gageodo island in the southwestern sea of the Korean Peninsula over three years (2009, 2012, 2013) and found a total of 253 species in 18 families. Geometridae had the greatest species richness, with 63 species, followed by Noctuidae, Erebidae, Crambidae and Sphingidae. The annual changes in species richness and abundance were not different and seasonal occurrence of species showed a unimodal pattern in which the numbers of species and individuals increased from April and May, peaked in June and decreased to September and October. Seven moth species (Pyralidae: Herculia drabicilialis Yamanaka, Didia striatella (Inoue); Crambidae: Clupeosoma pryeri (Butler), Demobotys pervulgalis (Hampson), Yezobotys dissimilis (Yamanaka), Syllepte cissalis Yamanaka; Erebidae: Hypena sinuosa (Wileman)) are reported for the first time in Korea.

• Clinical and Experimental Pediatrics
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• v.62 no.8
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• pp.292-296
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• 2019

Epidemiologic studies of Kawasaki disease (KD) have shown a new pattern or change of its occurrence suggestive of its pathophysiology or risk factors from the first patient with KD reported in 1961. The incidence of KD in Northeast Asian countries including Japan, South Korea, China, and Taiwan is 10-30 times higher than that in the United States and Europe. Knowing the true epidemiology of KD in each country and the availability of publications of KD epidemiology also could benefit general health care providers and general population. This would enable the early detection and treatment of KD, ultimately reducing the incidence of coronary artery complications and mortality. Therefore, efforts to investigate the true epidemiology of KD should be continued in every country using a questionnaire survey, National Health Insurance system data, or combined methods depending on each country's medical environment to ensure high-quality care of patients with KD.