• Journal of Mushroom
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• v.15 no.3
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• pp.150-154
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• 2017

A self-propelled turner was developed to produce mushroom compost at low costs and high efficiency, and the uniformity of compost produced by an excavator, compost mixer, and self-propelled turner was compared. The material of the compost was mixed with rice straw and chicken manure at a dry weight ratio of 3:1. After the final turning, internal temperature distribution, water content of the compost pile, ash ratio, and uniformity of the compost pile were examined. After the compost was completed, the water content was $69.9{\pm}0.54%$, $72.1{\pm}0.15%$, and $74.5{\pm}0.82%$, respectively. The length of rice straw was $47.5{\pm}15.4cm$, $24.9{\pm}10.1cm$, and $31.0{\pm}10.6cm$, respectively. The ash content in the dry weight of each compost was $25.0{\pm}6.2%$, $33.6{\pm}4.2%$, and $28.2{\pm}1.1%$, respectively. The deviation in the length of rice straw was affected by the linear velocity of the spinner in the compost mixer and the self-propelled turner, which were 21.5 m/sec and 9 m/sec, respectively. As a result, the most uniform mushroom compost was produced by the self-propelled turner.

• Parasites, Hosts and Diseases
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• v.23 no.1
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• pp.139-150
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• 1985

In order to determine the seasonal prevalence and population density of vector mosquitoes in Kyungpook Province, a survey based on average numbers of female mosquito per trap-night, were carried out during the period from May to November in 1984. Among the 34, 571 mosquitoes collected in Kyungsan county in animal shelters and human dwellings by light traps, approximately 45.0 per cent were Culex tritaeniorhynchus, 34.0 per cent Culex pipiens pallens, and 19.0 per cent Anopheles sinensis. By comparison, distribution of mosquito species in Ankang town, in which Japanese encephalitis had been reported in the past, were quite different and A. sinensis was the most abundant species, being constituted in 75.8 per cent, followed by C. tritaeniorhynchus(23.2 per cent), and C. pipiens pallens(O.6 per cent). In the general pattern of seasonal prevalence, C. tritaeniorhynchus first appeared in mid-June, and trapped in large numbers during the periods from mid-August to early September, showing a simple sharply pointed one-peaked curve, while C. pipiens pallens was found to be active through almost the entire season showing irregular curves with several peaks. The trend of seasonal distribution of A. sinensis was similar to that of C. tritaeniorhynchus, but the earliest dates of appearance and disappearance differed from that of C. tritaeniorhynchus. The results of hourly catches of mosquitoes by human baited traps have clearly shown the differences in the biting rhythm among the vector mosquitoes of this Province, such as the facts that C. tritaeniorhynchus and A. sinensis are rather constantly active all through a night with more or less inconspicuous peaks twice a night, while C. pipiens pallens exhibits an irregular curve, and the numbers of A. vexans nipponii, C. vagans and Armigeres subalbatus are very small and are not sufficient for estimating the biting rhythm. Four genera and fourteen species of larval mosquitoes collected from eighteen kinds of habitats which classified according to the categories followed by Bates (1949). The main breeding sites contributing to peak C. tritaeniorhynchus adult densities in this surveyed areas were evidently ricefields, ground pools, puddles and swamps and marshes, etc. Summarizing the results, this study indicated that the highest population density of C. tritaeniorhynchus was encountered in late August and early September, showing a simple sharply pointed one-peaked curve.

• Pediatric Infection and Vaccine
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• v.10 no.2
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• pp.200-207
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• 2003

Purpose : Malaria is known to have been eradicated for a few decades through persistent national health program in South Korea. However, malaria caused by Plasmodium vivax has started to reappear incidiously among military personnel near to DMZ since 1993. After then, the number of malarial cases have been increased abruptly year by year. We analyzed the children of indigenous malaria who were diagnosed by peripheral blood smear and malarial antibody test with regards to epidemiologic and clinical manifestations. Methods : The study 13 cases below 15 years of age, who were confirmed as vivax malaria during from January 2000 to August 2003. We retrospectively analyzed epidemiologic data, clinical manifestations, laboratory findings and therapeutic responses. Results : All of 13 cases were indigenous and tested positive for Plasmodium vivax. Of 13 patients, 9 were male and 4 were female. Mean age of onset was $9.5{\pm}3.6$ years old. Ilsan(n=9) was the most prevalent area, the most patients(n=11) were presented in summer (from June to August). A characteristic feature of periodic 3 day fever in patients with P.vivax infection was reported in only 2 among 13 cases. Thrombocytopenia was most prominent findings, which was accompanied by 12 of 13 patients and pancytopenia was appeared in 3 patients on this study. The therapeutic responses of hydroxycholoquine were very good in all cases, and abnormal laboratory findings were recovered and no relapse during follow-up period. Conclusion : Vivax malaria is indigenous in Korea near to DMZ, but recently endemic area seemed to be extended southward. Plasmodium vivax is the cause of indigenous malaria of children. As for children with high fever accompanying thrombocytopenia in endemic area of Korea, malaria must be included in differential diagnosis whether the type of fewer is periodic 3 day fever or not. Malaria antibody test is helpful as a screening test for malaria.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.36 no.4
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• pp.213-220
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• 2023

This paper presents a model simulating the folding process and collision dynamics of "ddakji", a traditional Korean game played using paper tiles (which are also referred to as ddakji). The model uses two A4 sheets as the base materials for ddakji. The folding process involves a series of boundary conditions that transform the wing part of the paper structure into a twisted configuration. A rigid plate boundary condition is also adopted for squeezing, establishing the shape and stress state of the game-ready ddakji through dynamic relaxation analysis. The gaming process analysis involves a forced displacement of the striking ddakji to a predetermined collision position. Collision analysis then follows at a given speed, with the objective of overturning the struck ddakji--a winning condition. A genetic algorithm-based optimization analysis identifies the optimal collision conditions that result in the overturning of the struck ddakji. For efficiency, the collision analysis is divided into two stages, with the second stage carried out only if the first stage predicts a possible overturn. The fitness function for the genetic algorithm during the first stage is the direction cosine of the struck ddakji, whereas in the second stage, it is the inverse of the speed, thus targeting the lowest overall collision speed. Consequently, this analysis provides optimal collision conditions for various compression thicknesses.

• The Korean Journal of Zoology
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• v.38 no.3
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• pp.405-416
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• 1995

The testis and the epididymis of sexually mature male bats were examined to investigate the process of spermiogenesis of Korean long-fingered bat (Miniopterus schreifersi fulignosus) using electron microscope. The ultrastructural findings were analysed on the basis of Lee's method (1992). Especially, we focused on the acrosome formation. The results are as follows: The spermiogenesis of the Korean long-fingered bat can be divided into ten phases on the basis of ultrastructural differentiation; three "Golgi" phases of early, mid and late stages, two "cap" and two "acrosome" phases respectively composed of early and late phases, one "maturation phase and two "spermiation" phases of early and late phases. The axoneme of sperm in the cauda epididymis is composed of nine outer dense fiber and a central singlet. The number 1, 5, 6, and 9 outer dense fibers are larger than others. In the Golgi phases, small vesicles are separated from Golgi vesicles and then appear to fuse into a large vesicle, and finally it contacd with the outerside of the nucleus. It suggests that proacrosomal material could be made in the cytoplasm before the Golgi vesicle formation and then it could be transferred into the Golgi vesicle and condensed more and more, and finally form acrosome, just as Lee;s suggestion (1992).m acrosome, just as Lee;s suggestion (1992).

• Korean journal of applied entomology
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• v.58 no.2
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• pp.89-99
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• 2019

In total, 654,362 adult mosquitoes were captured using black light traps in Gangwon-do Province of the Republic of Korea from 2012 to 2017. The collected mosquitoes were identified to the species level, placed in pools of up to 50 mosquitoes each, by species and date of collection, and screened for flaviviruses using a reverse transcription-polymerase chain reaction assay. A total of 276,224 adult mosquitoes were grouped in 7,721 pools for virus testing, and 68 flavivirus positive pools (0.9%) were detected. Flavivirus-positive products were confirmed by DNA sequencing. Japanese encephalitis viruses were detected in single pools collected from Chuncheon (2012, 2017: Culex pipiens, 2,728 and 1,111 mosquitoes, respectively), Hoengseong (2013: Culex orientalis, 19), and Gangneung (2017: C. pipiens, 724). All the Japanese encephalitis viruses detected were revealed as genotype V. Chaoyang viruses were detected in 63 pools of 5,055 Aedes vexans nipponii and a single pool of 585 C. pipiens collected in Gangwon-do Province from 2012 to 2017. Chuncheon was the region with the highest minimum infection rates (MIR, 0.32) and maximum likehood estimate (MLE, 0.33; confidence interval (CI) 95%, 0.23-0.46) of A. vexans nipponii for Chaoyang virus, followed by Hoengseong (MIR 0.30, MLE 0.30, CI 0.16-0.52) and Gangneung (MIR 0.21, MLE 0.21, CI 0.13-0.31). Monthly MIR and MLE values of A. vexans nipponii for Chaoyang virus were the highest in October (MIR 0.38, MLE 0.38, CI 0.07-1.25).

• Korean Journal of Environment and Ecology
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• v.21 no.1
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• pp.93-100
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• 2007

This study was based on the breeding process of the Pacific Reef Herons (Egretta sacra) bred in Aewol-eup, Jeju Island, for two years from February 2004 to June 2005. The clutch size of the pacific reef herons was $3.24{\pm}0.75$(N=17, range: $2{\sim}4$), and the egg-laying was at dawn or night intervals of one to three days. The major diameter of the egg(N=39) was $46.73{\pm}1.91mm$, the minor diameter thereof $34.06{\pm}0.83mm$, the weight thereof $27.67{\pm}3.12g$, and the thickness of the egg shell thereof $0.26{\pm}0.03mm$. In relation to the breeding cycles of the Pacific Reef Herons, the nesting or nest repairing was made from February to the end of April each year, the egg laying from the beginning of March to the beginning of May, the hatching from the beginning of April to the middle of May, and the nest departure from the middle of May to the end of July. The supplement brood was started immediately from May to June when the first brood had failed. The incubation period was $28.17{\pm}4.12(N=6)$ days, and hatched asynchronously. The fledgling period was $40.00{\pm}6.84(N=5)$ days, and bill, wing, tarsus and weight developments of early hatched nestlings were the fastest among the same brood. Compared with other egret species, the egg laying period of the Pacific Reef Heron was faster than that of the Black-crowned Night Heron, Little Egret and Great Egret, but later than that of Grey Heron, in Korea.

• Economic and Environmental Geology
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• v.43 no.5
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• pp.429-441
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• 2010

The Sunrise Dam gold deposit is located approximately 850 km ENE of Perth, in the eastern part of the Yilgam Craton, Western Australia. The mine has produced approximately 153 t of Au at an average grade of 4.2 g/t, which stands for the most significant gold discoveries during the last decade in Western Australia. The deposit occurs in the Laverton Tectonic Zone corresponding to the corridor of structural complexity in the Laverton greenstone belt, and characterized by tight folding and thrusting. The mine stratigraphy consists of a complexly deformed and altered volcaniclastic and volcanic rocks. These have been overlain by a turbidite sequence containing generally well-sorted siltstones, sandstones and magnetite-rich shales, which are consistently fining upwards. These sequences have been intruded by quartz diorite, ultramafic dikes, and rhyodacite porphyry (Archean), and lamprophyre dikes (Palaeoproterozoic). These rocks constitute the asymmetric NNE-trending Spartan anticline with north-plunging thrust duplication of the BIF unit. The deposit is located on the western limb of this structure. Transported, fluvial-lacustrine and aeolean sediments lie unconformably over the deposit showing significant variation in relief. Gold mineralization occurs intermittently along a NE-trending corridor of ca. 4.5 km length. The 20 currently defined orebodies are centered on a series of parallel, gently-dipping ($\sim30^{\circ}$) and NESW trending shear zones with a thrust-duplex architecture and high-strain characteristics. The paragenetic sequence of the Sunrise Dam deposit can be divided into five hydrothermal stages ($D_1$, $D_2$, $D_3$, $D_4a$, $D_4b$), which are supported by distinctive features of the mineralogical assemblages. Among them, the D4a stage is the dominant episode of Au deposition, followed by the $D_4b$ stage, which is characterized by more diverse ore mineralogy including base metal sulfides, sulfosalts, and telluride minerals. The $D_4a$ stage contains higher proportions of microscopic free gold (48%) than D4b stage (12%), and pyrite is the principal host for native gold (electrum) followed by tetrahedrite-group minerals in both stages.

• Korean Journal of Environmental Biology
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• v.26 no.2
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• pp.121-127
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• 2008

As a step toward developing conservation and restoration plans for an endangered species of the Oriental White Stork (Ciconia boyciana), we studied daily foraging behavior and ecology. We released two individuals, male and female, after enclosing study site with a fence and cutting out a part of two or three feathers of primaries. Research was conducted from 16 June to 11 July, 2007 for 25 days at Whawonri, Mewonmyung, Chungbuk province. We investigated diural and daily variation of foraging time budget, diet composition, and habitat selection of the feeding individuals. The storks quadratically invested for foraging time and resting time according to time of day, but no significant variation in the foraging time and resting time appeared daily over 25 days. As a result, the storks mainly used wetland as a foraging site in the center of the study area to that in the edge as well as to other types of habitat. The high usage for wetland in the center did not change over the 25 days while Rice field decreased and Wetland in the edge and Pathway increased. Female invested more time for foraging than male, but the foraging efficiency did not differ between them. We discussed the significance of foraging behavior and habitat selection for management plan.

• Journal of the Korea Society for Simulation
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• v.28 no.2
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• pp.23-33
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• 2019

A sub-munition which has low aspect ratio does not have flight stability and control of drag force under free-fall condition. In order to satisfy those problems, fin, which is called grid-fin, is designed instead of conventional flight fins and adapted to the sub-munition. The base model of the sub-munition is firstly set and numerical simulation of the model is conducted under transonic condition that is free-fall range of the sub-munition. Wind test is secondly performed to verify the simulation result. The result shows that grid fin adapted sub-munition has high drag force, but the flight stability is still needed. In order to enhance the flight stability, two additional grid-fins are designed which modify web-thickness and numerical simulations of modified models are conducted. As the results, the thinnest web-thickness grid-fin has the highest flight stability and still maintains high drag coefficient. Based on these results, design of grid-fin adapted sub-munition is completed, the path trajectory of the sub-munition can be predicted with acquired aerodynamic datum and it is expected that grid fin can be used to various shape of the flight vehicle and bomb.