• Advances in nano research
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• v.15 no.6
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• pp.567-577
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• 2023

The killing of bacteria by mechanical forces on nanopatterned surfaces has been defined as a mechano-bactericidal effect. Inspired by nature, this method is a new-generation technology that does not cause toxic effects and antibiotic resistance. This study aimed to simulate the mechano-bactericidal effect of nanopatterned surfaces' geometric parameters and material properties against three implant-derived bacterial species. Here, in silico models were developed to explain the interactions between the bacterial cell and the nanopatterned surface. Numerical solutions were performed based on the finite element method. Elastic and creep deformation models of bacterial cells were created. Maximum deformation, maximum stress, maximum strain, as well as mortality of the cells were calculated. The results showed that increasing the peak sharpness and decreasing the width of the nanopatterns increased the maximum deformation, stress, and strain in the walls of the three bacterial cells. The increase in spacing between nanopatterns increased the maximum deformation, stress, and strain in E. coli and P. aeruginosa cell walls it decreased in S. aureus. The decrease in width with the increase in sharpness and spacing increased the mortality of E. coli and P. aeruginosa cells, the same values did not cause mortality in S. aureus cells. In addition, it was determined that using different materials for nanopatterns did not cause a significant change in stress, strain, and deformation. This study will accelerate and promote the production of more efficient mechano-bactericidal implant surfaces by modeling the geometric structures and material properties of nanopatterned surfaces together.

• Journal of Chest Surgery
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• v.24 no.11
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• pp.1058-1067
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• 1991

High potassium cardioplegia is a widely accepted procedure to enhance myocardial protection from ischemic injuries associated with open heart surgery. Maintaining optimum osmolarity of the cardioplegic solution is one of the required conditions for an ideal cardioplegic solution Albumin is an frequently added component for maintaining optimum osmolarity of clinically used cardioplegic solutions. But the source of albumin is human blood so that the supply is limited and the cost of manufacturing is relatively high. Recently there are moves to minimized the use of blood product for fear of blood-associated infections or immunological disorders. In this experiment, we substituted mannitol or glucose for albumin added to the cardioplegic solution which has been used at the Wonju Medical College, To determine whether addition of mannitol or glucose instead of albumin in the cardioplegic solution can produce satisfactory myocardial protection during ischemia, three different groups of isolated rat heart perfused by modified Langendorff technique were studied. Wonju Cardioplegic Solution was selected as a standard high potassium[18mEq/L of K+] cardioplegic solution. Three kinds of cardioplegic solution were made by modifying the composition maintaining the same osmolarity[339$\pm$1mOsm/Kg] Isolated rat heart were perfused initially with retrograde nonworking mode and then changed to working mode. After measuring the heart rate, systolic aortic pressure, aortic flow, coronary flow, ischemic arrest by aorta cross clamp and cardioplegia was made maintaining the temperature of water jacket at 10oC. The heart was rewarmed and reperfused after 60min of ischemic arrest with intermittent cardioplegia at the 30min interval. The time to return of heart beat and the time required to get. Regular heart beat were observed after reperfusion. The recovery rate of the functional variables-heart rate, systolic aortic pressure, aortic flow, coronary flow and cardiac output were calculated and compared among the three groups of different cardioplegia-albumin, mannitol, and glucose. The wet weight and dry weight was measured and the water content of the heart as figured out for comparison. The time to return of heart beat was fastest in the albumin group, The functional recovery rates were best in the albumin group also. In the above conditions, albumin was the best additive to the cardioplegic solution compared to the mannitol or glucose.

• Journal of Bio-Environment Control
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• v.23 no.1
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• pp.31-38
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• 2014

Rooting agents and shading treatments were tested in two different experiments to determine their effects on the establishment success of hardwood cuttings of three highbush blueberry varieties 'Bluecrop', 'Duke' and 'Sunrise'. For the experiment with rooting agents, one-cm long bases of the cuttings were dipped into solutions of IBA or NAA for 5 s, both at 0, 500 and $1000mg{\cdot}L^{-1}$ in 50% ethanol, and were also treated with Rootone$^{(R)}$ powder. Determined 90 days after cutting, the percent rooting and root weight were increased by NAA at $500mg{\cdot}L^{-1}$ in 'Bluecrop' and 'Sunrise', while in 'Duke' IBA at $500mg{\cdot}L^{-1}$ was effective. These auxin treatments were found to work better than a commercial product Rootone$^{(R)}$. The rooting agent-induced increases in root development resulted in better shoot growth of the cuttings in all three varieties, as determined after 90 days of further growth in individual containers. In the experiment with shading treatments, different levels of the shading treatment (30 to 90%) were imposed over the cutting bed under no mist. In all three varieties, 30% shading increased the percent rooting and root and shoot growth, compared to no shading control. However, shading levels higher than 50% shading were found to be inhibitory for hardwood cuttings of highbush blueberries, especially under the environmental conditions with no mist system.

• Journal of Korea Game Society
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• v.11 no.4
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• pp.73-91
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• 2011

This paper investigates the possibilities of protecting game developers under the work-for-hire provision of copyright law. Fundamentally, the work-for-hire clause provides the authorship status to companies, not to game developers. Some argue that the clause is especially appropriate in software industries including game industries because they are new and different from typical types of copyright industries. However, game industries are different from software industries as well as typical types of copyright industries in that they have both cultural (artistic) as well as industrial characteristics. Game developers not being provided with the authorship status may be one of the reasons for the disputes related to turnover and knowledge leakage. This paper mainly suggests three kinds of solutions: first, protecting the moral right even in the work-for-hire provision; second, protecting game developers as coauthorship; and third, providing monetary compensation as it is in employee invention.

• Journal of Bio-Environment Control
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• v.15 no.3
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• pp.264-269
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• 2006

This experiment has investigated the effect of growth, yield and fruit quality of fig plant by different concentration of nutrient solution. Nutrient solution for pig plant were three concentrations of the balanced nutrient formula development by Japanese Horticultural Experiment Station. Plant height, number of leaves, stem diameter and number of fruit per plant were the best at 1/2 concentration. However, leaf length and leaf width did not show any difference in other treatment. Fruit length, fruit diameter and soluble solids did not differ from the different concentration of nutrient solutions. However, the fruit weight of fig plant was heavier by hydroponics than by soil culture in 2nd experiment. Early stage growth of fig plant was better at low concentration of nutrient solution and yield was better at high concentration. The result of this experiment will be utilized in the new application for fig plant hydroponics.

• Korean Journal of Cognitive Science
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• v.13 no.2
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• pp.47-59
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• 2002

Three experiments were conducted to investigate whether different types (common vs. uncommon) of prior-examples entail different effects in creative problem solving, and whether types/levels (rich or lean. common or uncommon) of background knowledge interact with types of prior-examples. It was found that the example types and the types/levels of background knowledge do interact and have some differential effects on generating novel and useful ideas. In Experiment 1 and 2. uncommon examples had a positive effect - generating many novel and useful ideas. regardless of background knowledge types. while common examples had positive effects, only when the background knowledge was somewhat uncommon In Experiment 3 it was also found that types (irrelevant,. single common. single uncommon, or multiple common + uncommon) of background knowledge seemed to influence differently on the ease of finding solutions: when background knowledge is diverse or not directly related to the task problem, uncommon prior examples produced much greater number of novel ideas than it was with single common or sin91e uncommon background knowledge. Implications of the present study were discussed. in relation to mental sets and fixation.

• Journal of Korean Society of Water and Wastewater
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• v.25 no.4
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• pp.479-488
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• 2011

Nanofiltration was performed with polyaluminium chloride solutions at different pH conditions to understand effects of inorganic compounds on aluminum hydrolysis products, i.e., three distinctive groups of aluminum species: polymeric Al at low pH; $Al(OH)_3$ at neutral pH; and ${Al(OH)_4}^-$ at high pH. The PACl solution was prepared to be approximately 4.0mM and adjusted to the designated pH. The influence of inorganic compounds on Al species fouling was investigated with 4.9mM $CaCl_2$ and 3.5mM $MgSO_4$ because $Ca^{2+}$, $Mg^{2+}$, $Cl^-$, ${SO_4}^{2-}$ are the most common inorganics in the drinking water. NF membrane fouling was measured by flux decline rate. The impact of $CaCl_2$ was not significant on the individual Al hydrolysis products fouling. However, the flux decline rate was drastically changed in the presence of $MgSO_4$. The concentration of particulate matters was considerably increased possibly due to interaction between Al species and ${SO_4}^{2-}$ where $MgSO_4$ was introduced. The particulates were accumulated on the membrane and enhanced the hydraulic resistance of the cake layer. In addition, conductivity removal of the membrane was decreased when Al-hydroxide was dominant due to reduction of membrane surface charge. The rejection of $Ca^{2+}$and $Mg^{2+}$ were considerably different, which implys that composition of inorganics paly a role on conductivity removal.

• The Korean Journal of Food And Nutrition
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• v.31 no.2
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• pp.264-271
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• 2018

The objective of this study was to investigate taste profiles and the correlation of Doenjang soup solution prepared with three different temperatures (5, 25, $45^{\circ}C$) and using an electronic nose (e-nose), electronic tongue (e-tongue), and descriptive analyses by trained panelists. A total of 17sensory attributes were generated from the descriptive analyses for the Doenjang soup solution. There were significant difference among the samples in the cooked soybean flavor, the cooked soybean odor, the soy sauce odor, the sweet odor, the sweet taste, and the sweet aftertaste attributes. The intensities of these sensory attributes tended to increase as the serving temperature of the Doenjang soup solution increased. There were seven volatile compounds detected by the electronic nose: ethanol, propanal, 2-methylpropanal, ethyl acetate, 3-methylbutanal, and beta-pinene. The intensities of the volatile compounds increased as the temperature of the Doenjang soup solution increased. On the other hand, the intensities of the basic tastes by the e-tongue decreased as the temperature of the Doenjang soup solution increased. In conclusion, the e-nose, e-tongue, and descriptive analysis results showed different correlations depending on the temperature of the Doenjang soup solutions.

• Steel and Composite Structures
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• v.33 no.3
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• pp.445-461
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• 2019

The ultrasonic guided wave-based technique has become one of the most promising methods in non-destructive evaluation and structural health monitoring, because of its advantages of large area inspection, evaluating inaccessible areas on the structure and high sensitivity to small damage. To further advance the development of damage detection technologies using ultrasonic guided waves for the inspection of welded components in structures, the transmission characteristics of the ultrasonic guided waves propagating through welded joints with various types of defects or damage in steel plates are studied and presented in this paper. A three-dimensional (3D) finite element (FE) model considering the different material properties of the mild steel, high strength steel and austenitic stainless steel plates and their corresponding welded joints as well as the interaction condition of the steel plate and welded joint, is developed. The FE model is validated against analytical solutions and experimental results reported in the literature and is demonstrated to be capable of providing a reliable prediction on the features of ultrasonic guided wave propagating through steel plates with welded joints and interacting with defects. Mode conversion and scattering analysis of guided waves transmitted through the different types of weld defects in steel plates are performed by using the validated FE model. Parametric studies are undertaken to elucidate the effects of several basic parameters for various types of weld defects on the transmission performance of guided waves. The findings of this research can provide a better understanding of the transmission behaviour of ultrasonic guided waves propagating through welded joints with defects. The method could be used for improving the performance of guided wave damage detection methods.

• Earthquakes and Structures
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• v.22 no.2
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• pp.169-184
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• 2022

The importance of seismicity in developing countries and the strengthening of buildings is a topic of major importance. Therefore, the study of several solutions with the development of new technologies is of great importance to investigate the damage on retrofitted structures by using probabilistic methods. The Federal Emergency Management Agency considers three types of performance levels by considering different scenarios, intensity and duration. The selection and scaling of ground motions mainly depends on the aim of the study. Intensity-based assessments are the most common and compute the response of buildings for a specified seismic intensity. Assessments based on scenarios estimate the response of buildings to different earthquake scenarios. A risk-based assessment is considered as one of the most effective. This research represents a practical method for developing countries where exists many active faults, tall buildings and lack of good implementable approaches. Therefore, to achieve the main goal, two high-rise steel buildings have been modeled and assessed. The contribution of buckling-restrained braces in the elastic design of both buildings is firstly verified. In the nonlinear static range, both buildings presented repairable damage at the central top part and some life safety hinges at the bottom. The nonlinear incremental dynamic analysis was applied by 15 representative/scaled accelerograms to obtain levels of performance and fragility curves. The results shown that by using probabilistic methods, it is possible to estimate the probability of collapse of retrofitted buildings by buckling-restrained braces and tuned mass dampers, which are practical retrofitting options to protect existing structures against earthquakes.