• Asian-Australasian Journal of Animal Sciences
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• v.28 no.9
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• pp.1259-1265
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• 2015

The present study was performed to study the genetic relationship of productive life with production and type traits of Korean Holsteins at first three lactations. The data for the analysis from 56,054, 28,997, and 11,816 animals of first, second and third parity cows which were born from 2006 to 2011 were collected by Dairy Cattle Improvement Center, National Agricultural Co-operative Federation. Milk, protein and fat yields adjusted for 305 days and average somatic cell score considered as production traits and analyzed type traits were stature, strength, body depth, dairy form, rump angle, rump width, rear leg side view, foot angle, front attachment placement, rear attachment height, rear attachment width, udder cleft, udder depth, front teat placement and front teat length. A multi trait genetic analysis was performed using Wombat program with restricted maximum likelihood animal model composed of fixed effect of birth year, farm and the random effect of animal and random residual effect according to the traits. Heritability estimates of productive life were between 0.06 and 0.13. Genetic and phenotypic correlations between production and productive life traits ranged from 0.35 to 0.04 for milk, 0.16 to 0.05 for protein and 0.18 to 0.02 f 15-0034 (2nd) 150520 or fat. Somatic cells score showed a negative genetic and phenotypic correlation with productive life and also udder type traits, indicating that the selection for higher udder traits will likely to improve resistance to mastitis and persistence in the herd. Among all dairy form type traits, udder characters such as udder cleft showed a significant relationship with productive life. However, a specific change of heritabilities or correlations were not observed with the change of parity. Moreover, further studies are needed to further confirm the significance of the above traits and the effect of parity on above relationships in order to minimize both voluntary and involuntary culling rates while improving herd health and maintaining high yielding dairy cows.

• Journal of Conservation Science
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• v.28 no.3
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• pp.265-276
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• 2012

Physicochemical properties of HBA epoxy resins were controlled by varying hardener mixture and reactive diluent to improve applicability for stone conservation. The epoxy risen comprises hydrogenated Bisphenol-A based epoxide (HBA), fast curing agent (FH), slow curing agent poly(propyleneglycol)bis(2- aminopropylether) (SH) and difunctional polyglycidyl epoxide (DPE). Talc was used as an inorganic additive. The changes in viscosity and temperature during curing reactions depending on the composition of the epoxy resins were investigated. Additionally, bending, tensile and adhesive strengths were measured to identify the effective mechanical strength in stone conservation. Finally various compositions of epoxy resin/inorganic additives were developed for stone conservation by controlling cure kinetics and mechanical properties.

• Applied Biological Chemistry
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• v.41 no.6
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• pp.457-464
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• 1998

For investigating the effect of amount of applied fertilizer with pig and chicken manures in the field, the number of soil bacteria were counted on the full strength conventional nutrient broth (NB) medium and its 100-fold dilution (DNB) medium. From the control soil samples without organic amendments, the number of bacteria on DNB medium was 5 to 10 times higher than that on NB medium. However, population density on NB medium was higher than on DNB medium from the treated soil with 60 and 120 Mg/㏊ for 3 years. Most of isolates from DNB plates did not grow on the NB plates. There were only grown on the 100-fold dilution medium, so it was called as DNB organisms. The DNB organisms were occupied as dominant group over 60% fo isolates in control soil. However, their occupation rates were rapidly decreased in the treatment soil with pig and chicken manures above 60 and 120 Mg per ha. These DNB organisms (oligotrophs) were significantly low population desities in the treatment soil with organic materials.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.1-12
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• 2002

The environmental effects were studied to estimate age and lactation stage adjustment coefficients in the primary linear traits of Holstein dairy cattle in Korea. Calving year month, classifier, age-month at classification and lactation stage were the environmental factors which significantly affected the most of linear traits at the level of 0.01. F values of Stature, strength, body depth, thurl with and rear leg side view were relatively higher in the effects of age-month, and dairy form, rear udder height, rear udder width, and udder cleft had relatively higher F values in the effects of lactation stage. Udder depth were affected highly by both age-month and lactation stage. Through the least square means of traits and the interpolation and smoothing obtained by the regression analysis of log and exponential transformed adjustment coefficients, age-month and lactation stage coefficients were estimated, and applied to real data to check the variation in the age-month and lactation stage effects. The estimated mean squares showed that the variation in all the linear traits significantly were decreased for the adjusted factors without the significant changes of variation in calving year month and classifier. That udder depth adjusted for both the age-month and lactation stage resulted in the decreases of variation in the both effects.

• Journal of Bio-Environment Control
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• v.6 no.4
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• pp.284-291
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• 1997

This study was conducted to evaluate the optimum hydroponic system and nutrient solution for shortening the early growth period and quality improvement of dendrobium ( Dendrobium Phalaenopsis) seedlings. Dendrobium seedlings with 3 to 4 leaves were transplanted in the deep flow technique(DFT) system, aeroponic system, and ebb and flow system with different concentration of balanced nutrient solutions recommended by the Japanese Horticultural Experiment Station. Growth characteristics of shoot and root were recorded and evaulated among treatments. For autumn cultivation, plant height was the longest at the DFT system with quarter concentration of nutrient solution, where aeroponic system with half concentration of nutrient solution. Aeroponic system stimulated the root growth but fresh weight was observed in the plots of DFT system. For spring cultivation, pH values increased up 7.5 at the DFT and aeroponic system, where EC values did not fluctuate regardless of cultural system. Ebb and flow system showed the best result in the growth of plant followed by BFT system and aeroponic system. Higher concentration of nutrient solution within this range of treatment was recommended for the growth promotion of leaf length and width in DFT system. In conclusion, growth responses differed depending on the cultural system, concentrations of nutrient solutions and duration of cltivation.

• Journal of Biomedical Engineering Research
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• v.19 no.5
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• pp.519-530
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• 1998

In this paper, the basic study on the design of the flexible keel of the energy-storage prosthetic foot was performed in order to Improve the walking performance and Increase the activities of the below knee amputees. Based on the analysis of the anthropometric data and the normal gait on two dimensional sagittal plane available In the literature, we presented a model of the basic structure of the flexible keel of the prosthetic foot. The model of the basic structure was composed of the simple beams, and linear rotational spring and damper. Laminated carbon fiber-reinforced composites were selected as the material of the basic structure model of the flexible keel In order to apply the high strength and light weight materials to the basic structure of the flexible keel of the prosthetic foot. The recoverable strain energy In response to the change of beam shape was calculated bur the finite element analysis and it was suggested that the change of beam shape could be the design variable in flexible keel design. The simulation process was systematically designed by using orthogonal array table in order to design the flexible keel structure which could store the more recoverable strain energy. finite element analysis was carried but according to the design of simulations by using the finite element program ABAQUS and the flexible keel structure of the energy-storage prosthetic foot was obtained from the analysis of variance(ANOVA). The dynamic simulation model of the prosthetic walking using the flexible keel structure was made and the dynamic analysis was carried but during one walk cycle. Based on the above results, an effective design process was presented for the development of the prosthetic fool system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.2
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• pp.689-696
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• 2017

The practical applications of ordinary high-fluidity concrete have been limited due to several drawbacks, such as high hydration heat, high amount of shrinkage, and non-economic strength development. On the other hand, due to its advantages, such as improvement of construction quality, reduction of construction cost and period, the development of high-fluidity concrete is a pressing need. This study examined the properties of high-fluidity concrete, which can be manufactured on the low binders using a viscosity agent to prevent the segregation of materials. The optimal viscosity agent was selected by an evaluation of the mechanical properties of high-fluidity concrete among six viscosity agents. The acrylic type and urethane type viscosity agents showed the best performance within the range where no material separation occurred. The mechanical properties were evaluated to examine the optimal amount of AC and UT viscosity agent added by mixing two viscosity agents according to the adding ratio and blending them together with high performance water reducing agent. When the ratio of the AC : UT viscosity agents was 5:5, it was most suited for high-fluidity concrete with low binders by increasing the workability and effect of the reducing viscosity.

• Journal of the Korea Organic Resources Recycling Association
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• v.28 no.2
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• pp.15-29
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• 2020

The aims of this study is to improve physical properties of the sewage sludge and the process sludge generated in the leachate treatment by mixing the dry fuel, to develop the neutral solidifing agents that reduce oder, and to recycle the sewage and the process sludges as landfill cover materials. The mixing ratio (W/W) of sludges and dry fuel was appropriate at about 1:1, and the mixed materials were shown to be homogeneous at that ratio. We could know that when the sludges were mixed with dry fuel, moisture contents and viscosities are reduced, and air passages are formed between particles and particles. The various mixing tests and odor tests showed that the neutral solidifing agent was effective for the odor reduction. The main ingredient of the solidifing agent is the ash of sewage sludge, enabling it competitive in waste recycling and production costs. The landfill cover, using developed neutral solidification agent, improved physical properties to satisfy the quality standards and to increase the compressive strength. It also proved to reduce the value of complex oder and the usage of solidification agent to 1/3 (3,000 to 1,000) and to 1/8 (50% to 6%), respectively, from the comparative study with alkaline solidified landfill cover. Further research is under way to prove that this can be mixed with general soil to be used as a soil improvement agent for plant cultivation.

• Journal of Korea Technology Innovation Society
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• v.12 no.3
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• pp.471-498
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• 2009

The ability to judge a country's scientific standing is vital for the governments and businesses that must decide scientific priorities and funding. In this paper, we analyze the output and outcomes from research investment over the recent years, to measure the quality of scientific research on national scales and to set it in an international context. There are many ways to evaluate the quality of scientific research, but few have proved satisfactory. To measure the quantity and quality of science in different nations, we analyzed the numbers of published research papers and their citations. The number of citations per paper is a useful measure of the impact of a nation's research output. Essential at a were acquired from SCI database by Thomson Scientific, which indexes more than 8,000 journals, representing most significant materials in science and engineering. The purpose of this paper is to evaluate and compare the output and outcomes among nations in a variety of viewpoints and criteria. One of the implications in response to the result of analysis is that sustainable economic development in highly competitive world markets requires a direct engagement in the generation of knowledge. Even modest improvement in healthcare, clean water, sanitation, food, and transport need capabilities in engineering, technology, and medicine beyond many countries' reach. Nations exporting natural resources such as gold and oil can import technology and expertise, but only until these resources are exhausted. For them, sustainability should imply investment in alternative agricultural and technological capabilities through improvements in their skills base. A strong science base does not necessarily leat to wealth generation. However, strength in science has additional benefits for individual nations, and for the world as a whole.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.7
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• pp.459-466
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• 2016

This study examined the effects of robot-assisted therapy on the motor and functional recovery of the lower limbs in 53 subacute stroke patients. Robot-assisted therapy was performed using Lokomat? (Hocoma AG, Zurich, Switzerland) for thirty minutes per day, five times a week for four weeks. The outcome measures used were the Fugl-Meyer assessment, Motricity index(MI), Functional ambulation category(FAC), Berg balance scale(BBS) for gait function and balance ability, 10m walking test, K-Modified Barthel Index(K-MBI) for the activities of daily living and Mini mental state examination (MMSE), and Beck's depression inventory(BDI) for depression. All patients recruited underwent these evaluations before and after the four week robot-assisted therapy. For the evaluation, the somatosensory evoked potentials were used to assess the functional recovery. Robot-assisted therapy on the lower limb after subacute stroke showed improvement in motor strength, gait function, and the activities of daily living. All changes in terms of MI, FAC, BBS, and K-MBI exhibited a statistically significant difference after the four weeks robot-assisted therapy. The somatosensory evoked potential result showed a correlation with the MI and K-MBI. Robot-assisted therapy is believed to facilitate the motor and functional recovery of the lower limb in subacute stroke patients.