• Korean Journal of Soil Science and Fertilizer
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• v.21 no.3
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• pp.289-295
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• 1988

An ordinary paddy variety Hwaseong and a high-yielding variety Samgang were taken under investigation to test the effect of top dressing of newly formulated three compound fertilizers on rice plants for at sprouting heads. The fertilizer formulate used were C. F. I (14-0-14; $NO_3-N$ and $NH_4-N$) and C. F. II (14-0-14; $NH_4-N$ only) and C. F. III (14-0-14 + OM 10%; $NO_3-N$ and $NH_4-N$). A field experiment was conducted on a plot of Gyuam series. The following results were obtained: 1. Effects of compound fertilizers at sprouting heads a. Hwaseong variety exhibited 5-10% yielding increases on the plots with application of 2nd compound fertilizer (I) and (II) compared to straight fertilizer of (I) and (III). Fertilization with 2nd and 3rd compound fertilizers gave the best result when they are done 15 days before heading. A yield increase of 3-5% was achieved when the fertilization was done 20 days before heading in the case of Samgang variety, but no beneficial effect was observed with an application 10 days before heading. b. Rate of barren grains was at the minimum in the compound fertilizer (II) plots of both Hwaseong and Samgang varieties. c. Content of $NO_3-N$ in soils and grain yield appeared to be positively correlated($r=0.618^*$) 2. Effects of heading fertilizers on artificially reduced conditions of soil a. No significant difference in Eh values were measured among reduced paddy soils. The compound fertilizer of (II) presented the best result in yield increases regardless of rice variety. b. Rate of barren grains in both varieties was observed at the minimum on the application of compound fertilizer of (II). c. No great difference of mineral contents was detected among plants from different treatments.

• Journal of Animal Science and Technology
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• v.53 no.1
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• pp.67-74
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• 2011

The aim of this study was to understand the management level of pathogenic bacteria in HACCP system implemented animal farms. Microbial samples were collected from manure, floor, compost depot, manure on belt, low milk tank, dust in laying house and egg collector in HACCP system implemented Korean beef cattle, dairy cattle, swine, and laying Hens farms. O157, O111 and O26 strains of E. coli were not detected in HACCP system implemented Korean beef cattle farm. The detection rate of E. coli from manure and floor in HACCP system implemented cattle farms (Korean beef cattle and dairy farm) was lower than those of non-HACCP system implemented cattle farm. Salmonella spp. was detected in HACCP system implemented cattle farms (Korean beef cattle and dairy farm). Compared with pervious studies, lower detection rate of Salmonella spp. at floor and compost depot in HACCP system implemented swine and commercial layer farms were indicated. In conclusion, implementation of HACCP system in animal farms would enhance the management level of biological hazard compare to normal animal farms.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.7
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• pp.762-770
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• 2005

Adsorption and biodegradation performance of chlorinated by-products such as trihalomethanes(THMs) and haloacetic acids(HAA5) on granular activated carbon were evaluated in this study. The coconut-based activated carbon was found more effective than others in adsorption of THMs due to larger pore volume of less than $20{\AA}$. The wood-based activated carbon was less effective than coconut- and coal-based activated carbon in adsorption nevertheless having larger pore volume and specific surface area than others. The maximum adsorption capacity(X/M) of coconut-based carbon for THMS was 1.1-1.5 times larger than coal based carbon and 14.1-31.4 times larger than wood based activated carbons. Activated carbon usage rate(CUR) of coconut-, coal- and wood-based activated carbons for chloroform were 9.4, 11.2 and 38 g/day respectively. In the evaluation of adsorption isotherm of THM species for coconut-, coal- and wood-based activated carbons, k value of chloroform was the lowest in the THM species, It menas that chloroform is difficult to remove by activated carbon adsorption. and BDCM, CDBM, bromoform are in the succeeding order of adsorption. In the evaluation of biodegradation rate, mean biodegradation rate was chloroform 7%, BDCM 5%, CDBM 4% and bromoform 3%, respectively THMs are difficult materials to be biodegraded. In the evaluation of characteristics of adsorption and biodegradation for HAA5 species, HAA5 species appear to be removed effectively by activated carbon. Most of the HAA5 are adsorbed at the beginning of operation periods and HAA5 except TCAA were almost biodegraded from bed volume of 2,000 and more than 90 percent of biodegradation of TCAA was started from bed volume around 4,000 and after that biodegradation rate was increased with increasing bed volume.

• Korean Journal of Poultry Science
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• v.37 no.3
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• pp.237-245
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• 2010

A survey of transovarially transmitted diseases, including salmonellosis [(pullorum disease; PD)/(fowl typhoid; FT)], mycoplasmosis, avian infectious anemia (CIA), and fowl adenovirus infection was conducted in the breeder chickens from August to December in 2009. The numbers of flocks sampled out were: Grand Parents Stock (GPS), 45; Parents Stock (PS) 1,018, Baeksemi breeder (BSB) 54. The seroprevalence of salmonellosis (PD/FT) were 0% (GPS), 3.2% (PS), and 3% (BSB), respectively. A total of 983 chicken farms were affected with FT outbreaks between 2000 and 2008. The incidence of FT in commercial broilers, Baeksemi, commercial layers, native chickens, and broiler breeders was 44.3%, 26.2%, 15.7%, 12.6% and 1.08%, respectively. Of the affected broilers, over 90% birds were under 2 weeks of age, indicating it was possible that they were infected with S. gallinarum via vertical transmission. The sero-positive flocks against Mycoplasma gallisepticum (MG) were 71.1% (GPS), 88.7% (PS), 88.7% (BSB), while the rates of positive flocks against Mycoplasma synoviae (MS) were 86.0% (GPS), 77.0% (PS), and 98.0% (BSB). In GP and parent farms, the detection rates on specific genes of CIA virus were 19/45 (42.2%), and 169/1039 (18.0%), respectively, whereas the seroprevalence of CIA were 86.0% in GPS and 93.7% in PS flocks. In addition, positive flocks of fowl adenoviruses were 4.4% (GPS), 2.7% (PS) and 9.35% (BSB), respectively. As the results, avian mycoplasmosis and CIA have been more prevailing in chicken breeder than avian salmonellosis and fowl adenovirus infection in Korea.

• Journal of the Korean Society of Marine Environment & Safety
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• v.29 no.7
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• pp.779-793
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• 2023

Intensive and long-term aquaculture activities in Korea have generated considerable amounts of organic matter, deteriorating the sedimentary environment and ecosystem. The Korean government enacted the Fishery Management Act to preserve and manage the environment of fish farms. Based on this, a fisheries environment assessment has been conducted on fish cage farms since 2014, necessitating the development of a scientific and objective evaluation method suitable for the domestic environment. Therefore, a benthic health index (BHI) was developed using the relationship between benthic polychaete communities and organic matter, a major source of pollution in fish farms. In this study, the development process and calculation method of the BHI have been introduced. The BHI was calculated by classifying 225 species of polychaetes appearing in domestic coastal and aquaculture areas into four groups by linking the concentration gradient of the total organic carbon in the sediment and the distributional characteristics of each species and assigning differential weights to each group. Using BHI, the benthic fauna communities were assigned to one of the four ecological classes (Grade 1: Normal, Grade 2: Slightly polluted, Grade 3: Moderately polluted, and Grade 4: Heavily polluted). The application of the developed index in the field enabled effective evaluation of the Korean environment, being relatively more accurate and less affected by the season compared with the existing evaluation methods like the diversity index or AZTI's Marine Biotic Index developed overseas. In addition, using BHI will be useful in the environmental management of fish farms, as the environment can be graded in quantified figures.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.2
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• pp.66-73
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• 2008

In this study, the characterization of minor livestock's excretions in terms of unit load generation and discharge was conducted by investigation and analysis of urine, manure and wastewater from stall of fowl, duck, horse, deer, goat and sheep. The results are summarized as follows: The unit load generation of fowl estimated by discharged amount and concentration analysis increases in egg layers due to the difference of planting head numbers, feed stuffs and manure disposal. In case of deer unit load generation by herbivora were calculated to be higher than data from existing references because of the gap between weight per livestock and the generation amounts of manure and urine. In case of sheep unit load generation by urine were analyzed two times higher than by manure but unit load generation by manure were reported higher than by urine in references, so large differences between this and previous study resulted.

• Journal of Sericultural and Entomological Science
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• v.2
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• pp.63-71
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• 1962

This work was to develope a more simple producing method of mulberry seedling with lower cost than the normal grafting method and the conclusions were found as; 1. There was no difference for the production of the seedling root when the young mulberry branch was graved in soil at the time it grown as 60∼80cm height. 2. It was found that the best result was obtained in case of 15 to 20 young branches of a mulberry shoot were graved instead of whole of them. 3. The seedling root quality of the clay soil graved was found better than the sand soil used, but root producing quantity was found as the same. 4. The fertilizing at the time of the young branch graving was not effective and also the continual fertilizing seemed not to be effective. 5. The seedlings root production was found that Kairyo Nezumigaeshi was best and Ichihei, Suwon Daeyop, Shimano-Uchi, Suwon No.3 and Suwon No.4 were followed of it. But Rosoh was found as poor. Morus alba L. was found as a better Species than Morus Lhou(Ser) Koidz and Morus bombycis Koidz for the production of the seedling root and its quality.

• Journal of Convergence for Information Technology
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• v.10 no.2
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• pp.1-8
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• 2020

The standardized procurement of supervisory cost for the construction of domestic Information and Communication Technology(ICT) facilities, which is announced by the Korea Engineering and Construction Association in May 2009, has been applied in the public institutions and private industries. However, the previous standardized procurement is not widely applied in recent years because the ICT and social economic environment have been rapidly changed and the previous equations to calculate the supervisory cost is not simplified. As results, the needs for a new standardized procurement has been increased and the Ministry of Industry, Commerce and Energy has published a notice with new standard procurement. In this paper, we provide the explanation of the background and the derivation process of the notice based on authors' experiences of project participation. As research method, we compare the previous mad-day cost of ICT construction and that of another area including electric facility construction, and then we explain a new procurement equation based on WBS(Work Breakdown Structure).

• Korean Journal of Environmental Agriculture
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• v.1 no.2
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• pp.129-133
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• 1982

This study was conducted to find out the resistance of rice varieties to ozone gas. Thirty eight rice varieties were exposed to 0.3 ppm $O_3$ gas for 3 hours. Damage symptom, percentage of destroyed leaf and chlorophyll contents were observed after $O_3$ fumigation. The results obtained are as follows. 1) Typical symptom of $O_3$ damage appeared to greyish subtle spots in Japonica type and redish brown subtle spots in Indica-Japonica hybrid type within rice leaf vein. 2) Resistant varieties to $O_3$ gas were Palgwangbyeo, Seokwangbyeo and Milyang 30, while sensitive ones were Gwanakbyeo, Jinjubyeo and Hankangchalbyeo. 3) Chlorophyll damage of rice leaves were higher in Nongbaeck, Dobongbyeo, Palgeum, Jinjubyeo than in Milyang 21, Podgwangbyeo, Josaeongtongil, Honamjosaeng, Hwanggeumbyeo. 4) The amount of chlorophyll damage showed highly significant positive correlation with that of leaf destruction.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.68-80
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• 1984

Garolim Bay is not only important fishing ground but also expected area for the tidal power plant. The construction and operation of tidal power plant will make change the ecosystem of this bay. Therefore, the actual fisheries stocks should be precisely understood for the effect estimation and overall utilization of the bay after the construction of the tidal power plant. During the study period from January through December in 1981, forty-six adult fishes species, 3 species of fish egg and 25 fishes larvae species have occurred in the bay. Considering the result on monthly distribution of eggs and larvae, the inner area of the bay seems to be important as nursing ground of larvae spawned at the outside bay in winter, e. g., Ammodytes personatus, and Enedrias sp. This inner bay is also major spawning ground for many species spawning in spring and summer, e. g., Gobiidae, Konosirus punctatus, Engraulis japonica, etc. Taking into consideration the annual mean production for three years($1978{\sim}1980$), there are two major fishing seasons. The one is in May-June for Enedrias larvae stock, and the another in October-November for big eyed herring stock. For the mariculture stocks, short necked clam, oyster and laver are important species. After construction of the tidal power plant, the migratory species, i. e., larvae of Enedrias and Ammodytes personatus, Mugil cephalus, Konosirus punctatus, etc. will be directly damaged by the interuption of migration route. On the otter hand, the change of physico-chemical factors of seawater will also affect the ecosystem of the bay. Consequently, for the overall utilization of the bay after construction, the actual ecosystem including the fisheries stocks, must bs precisely revealed, and the mechanical designs, e. g., sluice position and its demension, should be also considered with these biological characters of the bay.