• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.37 no.2
• /
• pp.198-208
• /
• 1992

Recently, a nursery mat made from rock wool has realized transplanting of the younger seedlings with the ordinary transplanting machines for Chibyo and Chubyo(3 and 4～5 leaved seedling, respectively). The seedlings defined as the 'Nyubyo' or 'Nursling seedlings' became possible to achieve economic profits from the reduction in both working time and costs. It being widely noticed as a strategy to solve the difficulties in current rice cultivation. The nursling seedlings are 1.4 to 2.5 leaves and height at 4.5 to 7cm, grown 4 to 7 days after seeding. They maintain still up to 50 to 80% of their nutrients in the endosperm, and can grow by using only their own nutrients for a certain period of time after transplanting. Nursling seedlings take 2 days in the nursery chamber at 32$^{\circ}C$ after seeding, and 2 days in the greening house at $25^{\circ}C$. This is only 4 days, all together, to make the nursling seedlings of 1.5 leaves which are ready for transplanting. Watering is only needed once at the sowing time. It only takes 1 or 2 waterings even to raise a seedlings for a period of 7 days. The number of nursery boxes can be reduced because it is possible to sow more densely(220 to 240g per box), thus it only needs seedlings of 15 to 16 boxes per 10 a which leads to a reduction in facilities and space needed. Temperature during the nursery period can be artificially adjusted more precisely which may lead to the prevention of temperature stress. The nursling seedlings can root rapid by because the crown roots from the coleoptile node begin to emerge immediately after transplanting. They show strong resistance to low temperature (12$^{\circ}C$) and deep-planting. There is no danger in the rooting of the seedlings even if half of their height is buried into the soil. Moreover, it can root at a rate of up to 65 to 80% even if the full height of the seedlings is buried. They show also strong resistance to submergence (10～15cm). The nursling seedlings tend to grow by producing tillers from lower nodes. It is therefore, necessary to control to keep the proper numbers of tillers per unit area. They have no fear in the delay of heading and their yield components can be so well balanced that the same level of yield was achieved with the nursling seedlings compared to that with Chibyo. It was further suggested that if the surplus tillers can be avoided by such cultivation practices, the number of grain per panicle can be kept greater and higher yield can be realized. Practical experiments with the nursling seedlings conducted in 1989 and 1990 by farmers in various areas showed exciting results. The nursling seedlings will become widely spread, or at least occupy an important position in Japanese and also in Korean rice cultivation techniques.tivation techniques.

• Journal of Korea Foundry Society
• /
• v.12 no.6
• /
• pp.471-479
• /
• 1992

For the last 2 decades, the bonding materials for the foundry sand and the foundry equipments with high performance have been developed and employed in the foundry shops. In those periods, the furan resins hardened in higher temperature have been replaced with the self-hardened ones in the room temperature. Simultaneously the various reclamation methods of the self-hardened furan resin sand have been developed in order to get the clean working environments, the reduction of solid wastes and the lower of production cost in the foundry. In this experimental study, the combustion reclamation method using the fluidized bed among the various methods was studied in order to reduce the L.O.I. and /or $N_2$ gas due to the deposition of the furan resins and the hardeners. Comparing the results of this experimental combustion reclamation method with those of the employed pneumatic method, the Surface Stability Index of the specimen made by combustion method is 30% higher than that of the latter one and L.O.I. decreases about 30%. The reclamation temperature of 650$^{\circ}C$ in this experimental fluidized bed would be recommended in the viewpoints of the reclamation period, the fuel consumption and the residual quantity of the furan resin. The formula determining the minimum fluidizing velocities according to the temperatures in the fluidized bed has been obtained.

• Korean Journal of Health Education and Promotion
• /
• v.21 no.1
• /
• pp.25-43
• /
• 2004

This study is aimed at determining stress and the degree of stress coping among nurse as well as such general characteristics as daily life styles, duty, and socio-demographic characteristics of that group. 525 nurses, from four university hospitals in Daejeon city underwent a self-administered questionnaire during the 3-week period from July. 21 to August. 9, 2003. The questions focused on general characteristics including： socio-demographic and duty characteristics, daily life styles, and stress and methods of coping with stress. Based on the distribution of degree of stresses, 66.1% of the study subjects were at the potential risk of stress, with the high risk group constituting 30.3% and the normal group 3.6%. The stress and the degree of stress coping were shown to be affected by socio-demographic and job-related characteristics as well as daily life styles. The group at higher risk of stress was shown to have a lower degree of coping with stress, implying that a lower degree of coping with stress would in turn heighten the occurrence of stress. Therefore, it is required to develop an effective strategy that includes stress-reduction programs available in the field and prompting further build-up of comprehensive stress-management programs.

• International Journal of Contents
• /
• v.13 no.2
• /
• pp.35-43
• /
• 2017

This study sought to measure the influence of HIMs' work environment changes on job stress, and to explore measures for improving job satisfaction among them. A total of 275 hospital HIMs' were surveyed using a structured questionnaire. Significant job stress impact variables were sorted out using a simple linear regression analysis. Then, through multiple linear regression analysis, multicollinearity was tested. Significant impact factors were identified from among the control variables, and job stress impact was measured. The survey revealed that in public hospitals where the EMR system has been implemented for a longer period, depression scores in HIMs' were increased. HIMs' job stress level was found to be affected by the following factors: computerization of their working environment, experience of depression, unemployment, and manpower reduction, as well as, their lifestyles, including leisure activities. The results of this study suggest that HIMs' job stress can be reduced through work environment improvement and improvement of their personal lifestyle habits.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2004.03b
• /
• pp.58-65
• /
• 2004

Recently, the top & down method with drilled shafts as a foundation of high rise building is often adopted for the purpose of construction period reduction and construction cost effectiveness. It is common to omit the loading test as a Quality assurance on account of the high capacity of drilled shafts for the top & down method. It seems that the capacity of drilled shaft in recent top & down method is beyond that of conventional loading test method.However, the quality assurance for the drilled shaft as foundation of high rise building becomes much more important since the drilled shaft should bear much higher working load. It may be a small scale test pile could be an alternative as a quality assurance for the drilled shaft with high capacities. Through a case study, this paper gives an idea for solving the limitation of the conventional loading test method for the quality assurance of drilled shaft with high capacities. In particular, this paper analyzed the scale effect for a small drilled shaft installed into bedrock, which could be used for an alternative.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2006.05a
• /
• pp.1-4
• /
• 2006

A down construction method is frequently used in these days to reduce popular discontent and to assure sufficient working space at early stage in downtown area. There are two main problems in the existing down construction method. One is a confliction between frame works and excavation works, and the other is a cold joint in retaining wall which is unavoidable due to a sequence of concrete placement and induces a water leakage. Therefore, a new method is needed to overcome these problems. The CWS (buried wale Continuous Wall System) method was developed by authors. By replacing RC perimeter beam with embedded steel wale, the steel frame works of substructure can be simplified and the water leakage can be prevented using continuous retaining wall. Consequently, the improved duality and reduction of construction period can be obtained from CWS method.

• Journal of the Korea Institute of Building Construction
• /
• v.6 no.2 s.20
• /
• pp.81-89
• /
• 2006

A down construction method is frequently used in these days to reduce popular discontent and to assure sufficient working space at early stage in downtown area. There are two main problems in the existing down construction method. One is a confliction between frame works and excavation works, and the other is a cold joint in retaining wall which is unavoidable due to a sequence of concrete placement and induces a water leakage. Therefore, a new method is needed to overcome these problems. The CWS (buried wale Continuous Wall System) method was developed by authors. By replacing RC perimeter beam with embedded steel wale, the steel frame works of substructure can be simplified and the water leakage can be prevented using continuous retaining wall. Consequently, the improved qualify and reduction of construction period can be obtained from CWS method.

• Journal of Animal Science and Technology
• /
• v.66 no.2
• /
• pp.279-294
• /
• 2024

Agriculture has played a significant role in the national economy, contributing to food security, driving economic growth, and safeguarding the dietary habits of the population. Korean agriculture has been compelled to focus on intensive farming due to its limited cultivation area, excessive input costs, and the limitations of agricultural mechanization. In the Republic of Korea (R.O.K), the concept of environmentally friendly animal agriculture began to be introduced in the early 2000s. This concept ultimately aims to cultivate sustainable animal agriculture (SAA) through environmentally friendly production practices, ensuring the healthy rearing of animals to supply safe animal products. Despite the government's efforts, there are still significant challenges in implementing environmentally friendly agriculture and SAA in the R.O.K. Therefore, the objective of this review is to establish the direction that the animal agriculture sector should take in the era of climate crisis, and to develop effective strategies for SAA tailored to the current situation in the R.O.K by examining the trends in SAA in the U.S. The animal agriculture sector in the U.S. has been working towards creating a SAA system where humans, animals, and the environment can coexist through government initiatives, industry research, technological support, and individual efforts. Efforts have been made to reduce emissions like carbon, and improve factors affecting the environment such as the carbon footprint, odor, and greenhouse gases associated with animal agriculture processes for animals such as cattle and pigs. The transition of the U.S. towards SAA appears to be driven by both external goals related to addressing climate change and the primary objectives of responding to the demand for safe animal products, expanding consumption, and securing competitiveness in overseas export markets. The demand for animal welfare, organic animal products, and processed goods has been increasing in the U.S. consumer market. A major factor in the transformation of the U.S. animal agriculture sector in terms of livestock specifications is attributed to environmentally friendly practices such as high-quality feed, heat stress reduction, improvements in reproductive ability and growth period reduction, and efforts in animal genetic enhancement.

• Journal of Veterinary Clinics
• /
• v.27 no.6
• /
• pp.746-750
• /
• 2010

Three military working dogs (MWDs) were diagnosed with perianal fistulae after a complete physical examination and rectal palpation. The initial treatment protocol was used with short-term oral ciclosporine (CyA) and ketoconazole and 0.1% topical tacrolimus ointment. When lesions were nearly healed, treatment was continued with 0.1% tacrolimus ointment only at a lower frequency. The lesions improved significantly within 2-8 weeks with no noticeable side effects. Complete recovery was determined at weeks 13, 6, and 4 for cases 1, 2, and 3, respectively. This combination protocol was effective at resolving or reducing perianal fistulae (PAF) lesions even communicating with anal sacs in three dogs. The major benefit of this protocol was the rapid reduction of fistulae lesions and this could be helpful to extend the pain-free period. Moreover, this protocol appeared cost-saving as well as time-saving option for PAF dogs.

• Wind and Structures
• /
• v.26 no.4
• /
• pp.191-204
• /
• 2018

This article presents a study of the largest-ever (height = 220 m) cooling tower using the large eddy simulation (LES) method. Information about fluid fields around the tower and 3D aerodynamic time history in full construction process were obtained, and the wind pressure distribution along the entire tower predicted by the developed model was compared with standard curves and measured curves to validate the effectiveness of the simulating method. Based on that, average wind pressure distribution and characteristics of fluid fields in the construction process of ultra-large cooling tower were investigated. The characteristics of fluid fields in full construction process and their working principles were investigated based on wind speeds and vorticities under different construction conditions. Then, time domain characteristics of ultra-large cooling towers in full construction process, including fluctuating wind loads, extreme wind loads, lift and drag coefficients, and relationship of measuring points, were studied and fitting formula of extreme wind load as a function of height was developed based on the nonlinear least square method. Additionally, the frequency domain characteristics of wind loads on the constructing tower, including wind pressure power spectrum at typical measuring points, lift and drag power spectrum, circumferential correlations between typical measuring points, and vertical correlations of lift coefficient and drag coefficient, were analyzed. The results revealed that the random characteristics of fluctuating wind loads, as well as corresponding extreme wind pressure and power spectra curves, varied significantly and in real time with the height of the constructing tower. This study provides references for design of wind loads during construction period of ultra-large cooling towers.