• KSCE Journal of Civil and Environmental Engineering Research
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• v.1 no.1
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• pp.33-42
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• 1981

Current standard code for R.C. design consists of two conventional design parts, so called WSD and USD, which are based on ACI 318-63 and 318-71 code provisions. The safety factors of our WSD and USD design criteria which are taken primarily from ACI 318-63 code are considered to be not appropriate compared to out country's design and construction practices. Furthermore, even the ACI safety factors are not determined from probabilistic study but merely from experiences and practices. This study investigates the safety level of R.C. flexural members designed by the current WSD safety provisions based on Second Moment Reliability theory, and proposes a rational but efficient way of determining the nominal safety factors and the associated flexural allowable stresses of steel bars and concretes in order to provide a consistent level of target reliability. Cornell's Mean First-Order Second Moment Method formulae by a log normal transformation of resistance and load output variables are adopted as the reliability analysis method for this study. The compressive allowable stress formulae are derived by a unique approach in which the balanced steel ratios of the resulting design are chosen to be the corresponding under-reinforced sections designed by strength design method with an optimum reinforcing ratio. The target reliability index for the safety provisions are considered to be ${\beta}=4$ that is well suited for our level of construction and design practices. From a series of numerical applications to investigate the safety and reliability of R.C. flexural members designed by current WSD code, it has been found that the design based on WSD provision results in uneconomical design because of unusual and inconsistent reliability. A rational set of reliability based safety factors and allowable stress of steel bars and concrete for flexural members is proposed by providing the appropriate target reliability ${\beta}=4$.

• Journal of Mushroom
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• v.18 no.1
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• pp.120-124
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• 2020

This study was conducted to provide basic data for setting a standard medium for winter mushroom cultivation. Investigation of medium composition in winter mushroom farms in Korea revealed that the types of medium used for each farm were slightly different and that the mixing ratio of the medium also varied. All farmers used corncob, rice bran, and beet pulp as the main media, and calcium carbonate and ground oyster shells were used at 1.0~3.8% to adjust the pH of the medium. Analysis of the physicochemical properties of the mixed media showed nitrogen content of 1.28~1.52%, carbon content of 45.7~48.5%, and C/N ratio of 30.7~37.9. The content of inorganic components was significantly different in each farm, depending on the type and amount of minerals in the mixed medium. Mycelial growth was the fastest at Farm 2, reaching 6.5 cm within 34 days of culture, followed by Farm 4 at 5.7 cm, whereas Farm 1, 3, and 5 showed similar growth. Mycelial density was high without any significant difference between farms. Survey of yield according to medium composition in each farm showed the highest yield in Farm 2 at 173.4 g/bottle, followed by Farm 1 at 168.4 g/bottle, whereas Farm 3 and 4 showed similar yield. However, Farm 4 had the lowest yield at 145.4 g/bottle. Therefore, mushroom yield was different depending on the medium composition in the farm, and thus selection of a medium that can be used universally in multiple mushroom farms was considered possible.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.35 no.2
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• pp.93-101
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• 1999

A simple experimental method was used in an attempt to realize the elevation of the fishing ability of purse seine in the sea area of Cheju Island, the changes of seine volume and tension in the purseline during pursing. Experiments carried out on the six types simplified reduced model seines which were made of knotless nettings. The nettings were woven in different leg length 4.3, 5.0, 5.5, 6.0, 6.6 and 7.7mm of polyester 28 tex two threads two-ply twine, and each of the seines were named I, II, III, IV, V and Ⅵ seine. Dimension of seine models were 450cm for corkline and 85cmfor seine depth, each seines rigged up 160g of float for a floatline and 50g (underwater weight) of lead for a leadline. These model purse seines were made of the scale of 1/200 of its full scale, a 120 ton in the near sea of Cheju Island. Designing and testing for the model purse seines were based on the Tauti's law. Experiments were measured in the observation channel of a flume tank at the static conditions set up shooting and pursing equipments. Motion of purse seine during purse line was recorded by the two sets video camera for VTR which were placed in top and front of the model seine. The reading coordinate of seine volume carried out by the video digitization system, disk data for the purseline tension. An analysis were performed on the changes seine volume and tension in the purseline during pursing. The results obtained were as follows: 1. The seine volume during pursing was largest for Ⅵ seine with smallest d/l followed by V, IV, III, II and I seines, and tension in the purseline was small. 2. Seine volume during pursing can be expressed by the following equation; CVt=l-EXP[｛2.79 (d/l）＋0.35｝t-33.37 (d/l) ＋ 0.57] Where CVt is volume ratio, d is twine diameter, l is leg length and t is pursing time (sec). 3. Tension in the purse line during pursing can be expressed by the following equation; T= 1- EXP ｛0.57t ＋ 13.36 (d/l)+2.97｝ Where T is tension (kg) in the purseline during pursing.

• Korean Journal of Soil Science and Fertilizer
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• v.36 no.5
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• pp.323-332
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• 2003

This study was carried out to provide information for the present status of soil pollution near abandoned old-zinc mining area through analysis of bound form and 0.1 N-HCl extractable concentrations of heavy metals in soils and plants. Feasibility of endemic plants for phytoremediation was evaluated by the investigation of vegetation in soils. Cd contents of the selected samples near old-zinc mining soils ranged from 0.2 to $42mg\;kg^{-1}$. Nonagricultural soils near the mining area contained great amounts of Zn, Pb, Cd, and Cu than the paddy and upland soils. Some Korean wild plants, Artemisia princeps, Artemisia montana, Erigeron canadensis, and Pueraria thunbergiana, were found to grow vigorously in the studied area. Among them, Artemisia princeps was selected as a possible phytoremediator for cleaning heavy metal contaminated soils. Artemisia princeps contained about 43 and $52mg\;kg^{-1}$ of Cd in their root and shoot as dry weight, respectively. Average contents of Cd in the rhizosphere soil, $15.68mg\;kg^{-1}$, was slightly higher than the soil-root interface soils, $14.1mg\;kg^{-1}$. Sequential extraction of Cd contaminated soils showed that average $2.4mg\;kg^{-1}$ (about 7%) of cadmium existed as exchangeable form and the average amounts increased as follows : adsorbed < organically bound < exchangeable << oxide carbonate << sulfide residual fractions. Amendment of organic by-product fertilizer in metal-contaminated soils promoted the growth of roots significantly as compared with the other treatments containing chemical fertilizer.

• Korean Journal of Heritage: History & Science
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• v.43 no.1
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• pp.260-279
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• 2010

The analysis on bibliography and field investigation of Callipogon relictus Semenov, 1898 (Korean natural monument number 218) shows that the size varies from country to country, and Korean specimens, for which male is 85~120mm and female is 65~85mm, are found to be the largest. The average diameter and length of egg are 2.60mm and 6.72mm respectively. The larva has milky color and is about 100~150mm in length. The pupa is nearly 70~110mm. An adult generally appears from June to September in Korea in the broadleaf forest of lowland, whereas it appears from June to July in China. It is known that the pupa largely feed on the old tree trunk of Carpinus laxiflora (Siebold & Zucc.) blume in Korea, but no such data have been reported in China and Russia, showing differences in host plants. While the larva period is not exactly known in Korea, it is reported to be two years in China. It appears that the species inhabits in very limited regions of approximately between geographical latitude $37.5^{\circ}{\sim}47.8^{\circ}$ and longitude $126^{\circ}{\sim}140^{\circ}$ including Korea, China and Russia. To conserve the long-horned beetle in Korea, this research drew out following some conclusions through analyzing the references and field survey data. First, it need to perform precise survey on the natural environment of occurring and collected area or place including host plant kinds, temperate, humidity, latitude, longitude etc. Second, habitat region must be designated as a restricted development area, and it need to exclude or reduce the damage factors to prosper reproduction of the species. Third, it is necessary to keep loosing cautiously artificial breeding individuals in the reported sites, not disturbing scope of natural populations. Fourth, it needs to educate or publicize many people importance and value of this species through many methods.

• Research in Plant Disease
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• v.27 no.1
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• pp.1-7
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• 2021

In August 2020, necrotic ringspots on leaves were observed on 20 from 143 Plantago asiatica plants in open fields in Eumseong, Chungcheongbuk-do. Eight symptomatic Plantago asiatica plants were subjected to investigation on viral infection by reverse transcription and polymerase chain reaction. Impatiens necrotic spot virus, tomato spotted wilt virus and cucumber mosaic virus were detected from the symptomatic plants. Two impatiens necrotic spot virus (INSV) isolates ('INSV-plantain kr1' and '-plantain kr5') were sequenced and analyzed by comparing L genomic segment, nucleoprotein (N) gene and non-structural protein S (NSs) gene sequences. The nucleotide sequence of 'INSV-plantain kr1' isolate (MW114834) was most closely related to that of a 'Phalaenopsis' isolate (GQ336991) from China in the L genomic segment. 'INSV-plantain kr1' and '-plantain kr5' isolates shared the highest identities with those from 'Pepe' isolate (LC384872) and 'J' isolate (AB109100) in the NSs gene, respectively, and with that from 'YSMi-SH' isolate (FN400773) in the N gene. Phylogenetic analysis based on L genomic segment grouped the INSV-plantain kr1 isolate together with isolates from Korea (LC384870), China (GU112505, GQ336991), and Italy (DQ425094). This is the first report on INSV in P. asiatica from Korea.

• Korean Journal of Environmental Biology
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• v.40 no.2
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• pp.148-156
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• 2022

Ecological occupation in irrigation ponds is a well-acknowledged fact that is essential for biodiversity conservation in agricultural ecosystems. However, there are few studies on the ecological functions and relationship between a paddy field and irrigation using macroinvertebrates in an environmentally friendly paddy field. The objective of this study is to identify the community and distribution characteristics of macroinvertebrates in an agricultural paddy field and irrigation pond ecosystems, and to provide basic data on the ecological function of an environmentally friendly paddy field. Macroinvertebrate sampling was conducted from May to September in an agricultural paddy field and irrigation pond in an environment-friendly paddy field in Boryeong city. We conducted a study to identify the distribution characteristics using macroinvertebrate species analysis, such as Functional Feeding Groups (FFGs), Habitat Oriented Groups (HOGs), rarefaction curve, and a two-way dendrogram. A total of 37 species of macroinvertebrates in 28 families, 13 orders were collected study during the period of the investigation. Dominant taxa of macroinvertebrates included Coleoptera, Hemiptera, and Odonata. In terms of FFGs, predators and gathering collectors accounted for approximately 70%, in relation to HOGs, and climbers and swimmers occupied more than 50% from both the paddy field and irrigation pond. With respect to the rarefaction curve, the irrigation pond (July) was high as E (S, 141)=18 species, while the paddy field (May) was comparatively low as E (S, 141)=9 species. In conclusion, our results revealed that macroinvertebrates, such as Notonecta triguttata, Peltodytes intermedius, Appasus major, Laccotrephes japonensis, Appasus japonicus, Sigara substriata, Enochrus simulans, and Sternolophus rufipes, were used as a habitat and spawning ground in both paddy field and irrigation pond. The irrigation pond appears to be a very important spawning ground for macroinvertebrates.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.1
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• pp.69-76
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• 2016

Purpose: The study was conducted to determine that photoreceptors of mouse having pigment in RPE(retinal pigment epithelium) can be damaged by blue-light and apoptosis of specific cells among photoreceptors are induced by blue-light, and to assist the investigation of AMD(Age-related macular degeneration) mechanisms and development of AMD drugs. Methods: C57Black mice were injured by irradiating $2800{\pm}10lux$ of 463 nm LED for 6 hours after 24 hours dark adaptation and eyes were enucleated 1, 3, 7 days. Damage of retina induced by blue-light was determined by western blotting GFAP(Glial fibrillary acidic protein) expression. In the light-injured retina, cell death of photoreceptors was determined by TUNEL(Terminal deoxynucleotidyl transferase dUTP nick end labeling) assay. ERK(Extracellular signal-regulated kinases), JNK, and SRC(sarcoma) expression were assessed by western blotting to determine regulated pathway. Blue light-injured retina were immunostained with antibodies against Opsin and Rhodopsin as markers of photoreceptors to compared the damage cone cells with rod cells. Results: After 1, 3 and 7 days from exposure to blue-light, thickness of retina was more decreased than control, and more decreased at nuclear layer than at outer plexiform layer and GFAP expression was increased day 1 after blue-light injured. While phosphorylated ERK and SRC protein expressions at day 1 were increased after blue-light injured, phosphorylated c-JUN was decreased. Fluorescence intensity analysis showed that markers of cone and rod cells were decreased after blue-light injured and Opsin was more decreased than Rhodopsin. Conclusions: The study suggests possibilities that the blue-light promotes retinal damage and causes apoptotic cell death via ERK and SRC pathway in mouse retina, and blue-light retinal damage is more induced cone cells apoptosis than rod cells directly.

• Korean Journal of Organic Agriculture
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• v.20 no.4
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• pp.715-725
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• 2012

This study was performed to make the method of food waste manufacturing for feeding to earthworm and different ratio of earthworm cast was investigated for applying vegetable plants that cultivated in a family or roof garden. We made conventional treatment of gardening soil and prepared soils with earthworm cast (the only fertilizer) at 30, 50, 70 and 100% for planting vegetable plants and then we studied its growth feature. The treatment was repeated three times with 12 weeks for each time. The cultivation of radish and chinese cabbage were managed at the same cultivation level for RDA standard cultivation method, and each sample of soils and plants was analyzed by appropriate analysis method. The growth investigation was performed 12 week after planting, and as for growth characteristics, height, leaf diameter, leaf number, leaf length, fresh weight and dry weight were investigated. The chemical characteristics, soils and plants, were surveyed. As for the growth characteristics investigated, radish and chinese cabbage showed the biggest growth in 70% and 50% treatment with average growth of all characteristics, height, leaf diameter, leaf number, leaf length, fresh weight and dry weight, respectively. Applying these results, a new equation for vermicast recommendation for radish and Chinese cabbage in summer (June-August) was presented. The earthworm cast 50% level with the gardening soil showed the high production in chinese cabbage. In case of radish, earthworm cast 70% with gardening soil level showed great growth, significantly.

• Tuberculosis and Respiratory Diseases
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• v.50 no.5
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• pp.568-578
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• 2001

Background : Lung cancer is frequently cited as an example of a disease caused solely by exposure to environmental carcinogens. However, there is a growing realization that the genetic constitution is also important in determining individual's susceptibility to lung cancer. This genetic susceptibility may result from functional polymorphims of the genes involved in carcinogen metabolism. In this study, the association between GSTM1 and CYP1A1 polymorphisms and the lung cancer risk in Korean males was investigated. Materials and Method : The study population consisted of 153 male lung cancer patients and 143 healthy male controls. The GSTM1 and CYP1A1 genotypes were determined by multiplex PCR and PCR-RFLP analysis. Result : There were no significant differences in the frequency of the GSTM1 null genotype between the cases and the controls. When the cases were categorized by their histologic type, the frequency of the GSTM1 null genotype in the small cell carcinoma group was higher than those of the controls(67.2% vs 55.9%), but the difference was not statistically significant(OR=1.772 ; 95% CI=0.723-4.340). The distribution of the CYP1A1 MspI genotypes among the cases were similar to those among the controls. When the cases were grouped by their histologic type, the ml/m1, ml/m2, m2/m2 genotypes frequencies among the small cell carcinomas(23.0%, 38.5%, and 38.5%, respectively) were significantly different from those of the controls(36.4%, 46.2%, and 7.4%, respectively, p<0.05). When the m1/m1 genotype was used as a reference, the ml/m2 and m2/m2 genotypes were associated with an increased risk for small cell lung cancer(ml/m2 genotype : OR=1.337, 95% CI=0.453-3.947 ; m2/m2 genotype : OR=3.374, 95% CI=1.092-10.421). Conclusion : These results suggest that the GSTM1 and CYP1A1 genotypes may be a genetic determinant of the risk for lung cancer, particlulary small cell carcinoma. Further investigation is needed to confirm these results.