• Korean Journal of Fisheries and Aquatic Sciences
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• v.40 no.1
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• pp.24-30
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• 2007

We developed an ecosystem indicator (EI) for the coastal and offshore areas of Korean waters. One of the major scientific challenges of this undertaking was to translate broad policy statements for ecosystem-based fisheries management (EBFM) into practical terms. Fish reproduction potential (FRP) was defined as an EI to describe the reproductive probability of adult fisheries resources in Korean waters. The FRP was estimated as the ratio of adult fish composition to total catch, catches (in metric tons) by species and by ecosystem, and fishery effort (in horse power per metric ton). The FRP indices of the East/japan Sea Ecosystem (EJSE), Yellow Sea Ecosystem (YSE), and East China Sea Ecosystem (ECSE) began to decrease after the mid-1980s, and the current indices have decreased further, at 0.63 (EJSE), 1.22 (YSE), and 0.68 (ECSE) index points compared to the indices of 1975, when similar catch amounts were recorded. Lower FRPs in the Korean marine ecosystems were the result of higher proportion of immature fisheries resources in the total catch. Because this kind of ecosystem-level indicator is thought to reflect scientific approaches to EBFM and to provide an important tool for assessing the current status of marine ecosystems with respect to both quantity and quality, more EIs should be developed for Korean waters.

• Journal of Microbiology and Biotechnology
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• v.9 no.2
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• pp.201-205
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• 1999

The effects of growth temperature and a carbon source on the expression of $\beta$-galactosidase gene of Lactococcus lactis ssp. lactis ATCC 7962 (L. lactis 7962) were investigated. At $25^{\circ}C$, L. lactis 7962 had a higher $\beta$-galactosidase activity than cells grown at $30^{\circ}C$ or $37^{\circ}C$, although cells grew most quickly at $37^{\circ}C$ The highest $\beta$-galactosidase activity was observed in cells grown in M17 with lactose (l %) followed by cells grown in a galactose (1 %) medium. L. lactis 7962 exhibited the minimum $\beta$-galactosidase activity in glucose media, indicating catabolite repression. When the cellular levels of $\beta$-galactosidase mRNA were examined using slot blot hybridization, no significant differences were observed between cells grown at $25^{\circ}C$ and cells at $30^{\circ}C$ or $37^{\circ}C$ in the same media. This suggests that the quantity of $\beta$-galactosidase mRNA may not be the reason for the higher $\beta$-galactosidase activities of L. lactis 7962 at $25^{\circ}C$ The level of ccpA (Catabolite Control Protein) transcript remained almost constant during the exponential growth phase irrespective of a carbon sourse.

• Journal of Korean Society of Steel Construction
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• v.12 no.1 s.44
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• pp.17-28
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• 2000

The current specifications for bridge decks requires the same amount of upper and lower reinforcement mats. There have been many empirical activities that the partial elimination of upper reinforcing bars was not caused the structural integrity of a deck. A simplified method is derived based on thin plate theory for three and four-girder-span bridge decks. A simplified method for bridge deck considering the effect of girder deflection is proposed based on a closed-form solution that shows good agreement with the results of finite element models. In this research, a new design approach for deck slabs is proposed based on the simplified method. The negative bending moments in a deck can be evaluated with the simplified method based on the position of a wheel load, the aspect ratio and relative stiffness and the span length. This new approach can lead to a significant reduction of the quantity of the top reinforcing steel bars in a deck. Reducing the quantify of the top reinforcement not only reduces the construction costs for bridge decks, but also reduces the corrosion of reinforcement to a minimum.

• Journal of the Society of Naval Architects of Korea
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• v.36 no.3
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• pp.107-114
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• 1999

Design Axiom proposed by N. P. Such consists of Independence Axiom & Information Axiom. Based on the Independence Axiom, it is very useful specially for early design stage such as conceptual design to generate the design alternatives by considering both functions and structures of product. Since the Information Axiom shows that the design solution should have a least information to be the best one among the many alternatives, this axiom can be used for the best selection purpose during the preliminary design stage. In this paper, the possibility of Design Axiom in marine design application is checked by carrying out three examples of marine design. In the conceptual design of thruster, it is proven to use the Independence Axiom very effective by relating directly functional requirements with design parameters, one by one. In main engine selection example, Information Axiom is used to select best solution among alternatives by choosing the one having the minimum information quantity. For similarity based design in which the selection of changing design variables and the amount of those are important, it is proved that design axiom applied to Barge design case would be very effective and useful. As functional requirements and constrains were not clarified in early design stage, design axiom shows some difficulty for larger system design like ship which is basically carried out by an incremental and iterative process.

• Spatial Information Research
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• v.20 no.6
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• pp.45-57
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• 2012

The street trees in the urban areas provide an comfortable environment to the pedestrians and drivers and play important roles to absorb the carbons. Therefore, it is necessary to acquire and manage efficiently the location, height, and crown width of street trees. This study suggests a methodology to provide quantitative information of the street trees in urban areas including the quantity, location, height, and crown width of the trees. Therefore, it is more appropriate to add functionality of changing size of the crown width of the trees in the method. In addition, the positions of the street trees were selected using the fact that street trees are generally planted along the road in a straight line. An experiment on extracting street trees was conducted in parts of Osan-si, Gyeonggi-do and the suitability of the suggested methodology was evaluated by comparing the results to a 1/1,000 digital map. Through the experimental results, the minimum, maximum, and the root mean square errors of the position of street trees were 0.5m, 1.9m, and approximately ${\pm}0.4m$, respectively.

• Journal of Environmental Health Sciences
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• v.9 no.2
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• pp.75-81
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• 1983

The Biochemical Oxygen Demand(BOD) indicates that microbes are proliferating or that oxygen is being spent by breathing action when examining water under the same aerobic condition. In this research of the mesurement of BOD are the poisonous elements of heavy metal ions such as Cu-ion, Cr-ion, Pb-ion and Zn-ion. They exert an unfavorable influence in the analysis of BOD and research was performed to provide certain data of minimum negative influence by the poisonous matters. The results of the research confirm that heavy metal ion(Cu, Cr, Pb, Zn) do direct an influence upon the normal growth of aerobic microbes in actual tests of chemical analysis of portable water or sewage. The most critical concentration for a negative effect on lowering oxygen quantity and disturbing the aerobic mocrobes normal growth was found to be 0.01 mg/l. Therefore, test results are not valid if the heavy metal concentration is to or greater than 0.0mg/l, To improve comprehension through out the research the author uses the following abbreviations: 1. The Cu-ion is to be excluded before experimental analysis if it is over 0.01mg/l inorder to obtain a real value for the BOD. 2. The Cr-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD. 3. The Pb-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD. 4. The Zn-ion is to be excluded before experimental analysis if it is over 0.01mg/l in order to obtain a real value for the BOD.

• Journal of Advanced Marine Engineering and Technology
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• v.22 no.1
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• pp.67-76
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• 1998

Friction materials for brake linings and clutches have severe performance requirements. The principal function of such frictional elements is to convert kinetic energy to heat, and then either to absorb or to dissipate heat. In order to achieve these objectives, the coefficient of friction must be as high as possible, independent of variations in operating conditions, and the necessary energy conversion must be accomplished with a minimum of wear on the contacting parts. In this study, Al powder, Al bronze powder and Mo powder used in general for automobile brake was sprayed on automobile brake disc to restrain rust and to maintain friction performance. Dynamo and corrosion tests have been carried out. It is concluded that the sprayed disc with Al bronze powder has the most improved frictional performance and anti-corrosive characteristics. The main results obtained can be summarized as follows; 1. From the corrosion current density test for gray cast iron and sprayed disc with powders of Al, Al bronze and Mo, it was cleared that the spray treatment with Al bronze powder showed the most superior anti-corrosive characteristics than other powders. 2. By anode polarization toward the noble direction from corrosion potential, corrosion current density with sprayed brake disc by Al-bronze powder was the lowest. 3. Mean frictional coefficients obtained from dynamo test are as follows : the sprayed disc with Al(99.99%) powder was 0.190 ; the sprayed disc with Al-bronze powder was 0.312 ; the sprayed disc with Mo powder was 0.257 ; the non-sprayed disc of gray cast iron was 0.331. In the case of the sprayed disc Al-bronze powder showed the most excellent frictional characteristics . 4. Amount of burnish quantity obtained from burnish test by dynamometer is as follows : the sprayed disc with Al-powder was 1.079 mm : the sprayed disc with Al-bronze powder was 0.155 mm : the sprayed disc with Mo powder was 0.253 mm : the non-sprayed disc of gray cast iron was 0.241 mm. Al-bronze powder also showed the most excellent burnish characteristics.

• Journal of Nutrition and Health
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• v.35 no.5
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• pp.531-543
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• 2002

To assess the dietary therapy compliance of non-insulin-dependent diabetes mellitus (NIDDM) patients living in Daegu, we evaluated diet adequacy levels by index of nutritional quality (INQ), nutrient adequacy ratio (NAR), mean adequacy ratio (MAR), and dietary variety score (DVS) with food exchange system and Korean recommended dietary allowances (KRDA). One day dietary intake was measured by 24 hour recall method for 229 subjects over 20 years of age. Average daily energy intake was 1444 kcal. The relative ratio of carbohydrate, protein and fat in terms of energy intake was 69.4：14.5：16.0. The nutrient adequacy ratio (NAR) for Vitamin A, B$_2$, calcium were lower than 0.5 and MAR was 0.65. It appeared that the consumption of each food group as compared to prescribed food exchange unit was insufficient, in the order of dairy group (10.2 $\pm$ 25.2%), fruits group (58.2 $\pm$ 71.2%) and oils & fats group (42.9 $\pm$ 42.0%). The dietary variety score (DVS) was evaluated as an useful tool for diabetes' meal management when we accept minimum intake as 0.3 of food exchange unit. We found significant correlation between food groups and anthropometric indices: cereals group and % total body fat (r = 0.251, p < 0.01), meat group and waist circumference (r = 0.241, p < 0.01), vegetables group and WHR(r = 0.139, p < 0.05), and oils poop and WHR(r = 0.165, p < 0.05). from these results, we concluded that overall status of dietary intake of NIDDM patients in Daegu area was insufficient not only in quality but also in quantity. It is suggested that nutrition education for NIDDM patients should stress on balanced food consumption to meet proscribed amount by six food group to improve the inadequacy of dietary status.

• Journal of Biosystems Engineering
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• v.30 no.6 s.113
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• pp.333-339
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• 2005

The pesticide is raising public interest in the world, because it causes damage to an environmental pollution and the human health remaining agricultural products and an ecosystem, in spite of the advantages. Particularly, each country restricts the residual pesticide and induces observance about the safety and usage standard so that they can control the amount of pesticide used and defend the safety of agricultural products. The habitual practice for the analysis of the residual pesticide depends on GC (gas chromatography), HPLC (high performance liquid chromatography) and GC/MS (gas chromatography/mass spectroscopy), which triturate the fixed quantity of samples, abstract and purify as a suitable organic solvent. These methods have the highly efficient in aspects of sensitivity and accuracy. On the other hand, they need the high cost, time consuming, much effort, expensive equipment and the skillful management. Carbofuran is highly toxic by inhalation and ingestion and moderately toxic by dermal absorption. As with other carbamate compounds, it is metabolized in the liver and eventually excreted in the urine. The half-life of carbofuran on crops is about 4 days when applied to roots, and longer than 4 days if applied to the leaves. This research was conducted to develop immunoassay for detecting carbofuran residue quickly on the basis of surface plasmon resonance and to evaluate the measurement sensitivity. Gold chip used was CM5 spreaded dextran on the surface. An applied antibody to Immunoassay was GST (glutathione-s-transferase). The association and the dissociation time were 176 second and 215 second between GST and carbofuran. The total analysis time using surface plasmon resonance was 13 minutes including regeneration time, on the other hand HPLC and GC/MS was 2 hours usually. The minimum detection limit of a permissible amount for carbofuran in the country is 0.1 ppm. The immunoassay method using surface plasmon resonance was 0.002 ppm.

• Korean Journal of Environmental Agriculture
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• v.31 no.2
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• pp.113-121
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• 2012

BACKGROUND: The Doam watershed in Korea has been managed for the reduction and the prevention of non-point source pollution since 2007. Especially, the water quality of the Doam reservoir is a primary issue related to the Doam dam reoperation. We have carried out the modeling to evaluate the water quality based on suspended solids (SS) of the Doam watershed and the Doam reservoir. Two powerful hydrological and water quality models (HSPF and CE-QUAL-W2) were employed to simulate the combined processes of water quantity and quality both in the upland watershed of the Doam reservoir and the downstream waterbody. METHODS AND RESULTS: The HSPF model was calibrated and validated for streamflow and SS. The CE-QUAL-W2 was calibrated for water level, water temperature, and SS and was validated for the only water level owing to data lack. With the parameters obtained through the appropriate calibration, SS concentrations of inflow into and in the Doam reservoir were simulated for three years (2008, 2004 and 1998) of the minimum, the average, and the maximum of total annual precipitation during recent 30 years. The annual average SS concentrations of the inflow for 2008, 2004, and 1998 were 8.6, 10.9, and 18.4 mg/L, respectively and those in the Doam reservoir were 9.2, 13.8, and 21.5 mg/L. CONCLOUSION(s): The results showed that more intense and frequent precipitation would cause higher SS concentration and longer SS's retention in the reservoir. The HSPF and the CE-QUAL-W2 models could represent reasonably the SS from the Doam watershed and in the Doam reservoir.