• KSBB Journal
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• v.23 no.6
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• pp.551-553
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• 2008

In order to optimization germination condition of broccoli, we carried out germination ratio experiment under soaking time, soaking temperature, oxygen concentration. The germination ratio results 98.5% following as soaking water having 10 ppm DO(demanded oxygen) during 4 hr at $20{\sim}30^{\circ}C$. The result of provide the dissolved oxygen water, when the concentration of oxygen water were 7, 12 ppm, germination ratio were observed about 76%, 92%. Also, we showed the growth rate of 2 times in 12 ppm compared with 7 ppm. Consequently, germination ratio of broccoli increased cultivation condition at soaking water having high concentration oxygen more than supply to oxygen water of high concentration.

• Journal of Food Hygiene and Safety
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• v.27 no.3
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• pp.285-289
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• 2012

In this study, the veridical efficacy of an aquatic disinfectant tablet composed to calcium hypochlorite against red sea bream iridovirus (RBIV). A veridical efficacy was determined with the viability of RBIV contacted with the disinfectant in viral stock cultured in fat head minnow cell line. An aquatic disinfectant tablet and RBIV were reacted on the distilled water (DW), hard water (HW) or organic matter suspension (OM) condition. On DW and HW condition, RBIV was inactivated with 25,000 fold dilutions of an aquatic disinfectant tablet. With the investigation of the antiviral effect of the disinfectant on OM condition, RBIV was inactivated on 22,000 fold dilutions of an aquatic disinfectant tablet. As an aquatic disinfectant tablet possesses veridical efficacy against RBIV, the disinfectant solution can be used to limit the spread of cultured marine fish viral disease.

• Journal of Construction Engineering and Project Management
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• v.1 no.3
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• pp.45-51
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• 2011

During disaster response, prioritization of limited resources is one of the most important but challenging tasks. At the same time, it is imperative to timely provide to the rescuers with the adequate heavy equipment to facilitate lifesaving operations. However, supply of high demand equipment is usually insufficient during the initial phase of disaster response, challenging lifesaving operations. At the same time, resources outside of the disaster affected zone converge into the area to assist the response efforts, which is the effect of convergence that often made resource coordination challenging in large scale disasters. Meanwhile, the initial condition of the disaster is usually best known by civilians already at the area before and during impact of the disaster. The knowledge of the civilians is not always received and considered by the responding organizations. With the help of these civilians, critical information such as victim location, infrastructure damage, and risk condition could be better know before any response actions are taken. To efficiently collect information and utilize the converging resources, this paper proposes a geospatial information repository for initial condition reporting and update to guide search and rescue operations and deployment of equipment with safety considerations for the rescuers in large scale disaster response scenarios.

• Journal of the Society of Naval Architects of Korea
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• v.59 no.2
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• pp.89-95
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• 2022

The stability of the existing ships has been evaluated through numerical calculations in the steady-state, but recently the IMO proposed a new stability assessment criteria that the stability is evaluated in the state in which environmental loads from such as waves and wind act like the loads under actual ship operating conditions. In this study, IMO 2nd generation stability assessment method and procedure were summarized for the dead ship condition, and Direct Stability Assessment (DSA) was performed on 13K chemical tanker through basin model test. The model test is performed in the ocean engineering basin to implement wave and wind loads, and environmental conditions for waves were set height and period of the incident wave, considering the regular wave and wind generation range reproducible in the ocean engineering basin. In addition, to consider the effect of wind speed, the Beaufort Scale for wind speed was applied in the model test.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.16 no.6
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• pp.49-62
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• 2013

As ten years have passed since national parks were adjusted and released inceptively, it is the time for evaluating the effectiveness of the national park policy and improving it on the basis of the evaluation result. In this study, the method of appraising the environmental and socio-economical ripple effect on the implementation of national park regulation were provided, based on the institutional consideration, the environment analysis, the survey of residents consciousness, the statistical analysis and so on. It is applied to target sites where were released from national parks, and the policy direction was suggested for sustainable use and management of national parks. National parks, that exhibit various characteristics depending on geographical and local conditions, were categorized through the statistical approach. Released sites from Seoraksan National park, where was categorized as the core national park for sustainable use and management, were evaluated environmentally based on the time-series analysis of environmental thematic maps and socio-economically based on the survey on residents perceptions. As a result of this study, the environmental effect of released sites has been declined or threatened, and the residents' economic, social and living condition in these areas are still not improved(p<0.05) since the adjustment of national parks. Based on the policy approach reflecting regional characteristics, natural resources are kept and enhanced for the sustainable use and management of national parks. And a consensus on the national park policy of national park should be developed between local residents and voluntary participation and public awareness should be attracted from them, based on the construction and the supplement of the infrastructure.

• Korean Journal of Medicinal Crop Science
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• v.20 no.3
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• pp.171-176
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• 2012

This study was conducted to investigate the effect of atmosphere-leaf vapor pressure deficit (VPD) in Allium microdictyon Prokh. and Allium ochotense Prokh. The vapor pressure deficit (VPD) was rapidly increased with increasing temperature and decreasing relative humidity. Taken as a whole, the stomatal transpiration reaction was slightly late with increading of VPD. Maximum photosynthetic rate at high-VPD condition was 5.98 ${\mu}mol$ $CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ in Allium microdictyon, which was a little lower than 6.59 ${\mu}mol$ $CO_2{\cdot}m^{-2}{\cdot}s^{-1}$ in Allium ochotense, respectively. After 2 p.m, stomatal transpiration of Allium microdictyon at the high VPD condition were rapidly decreased. Ci/Ca began to decline sharply at 8 a.m and showed the lowest value at 2 p.m, The results showed that Ci/Ca decreased with being used $CO_2$ in the mesophyll intercellular space for photosynthesis. In high VPD condition, The water potential values showed the highest at 5 a.m, and the lowest at 1 p.m in high VPD condition. The water saturation deficits (WSD) in high VPD condition showed about 1.5 times higher than in low VPD condition. The results indicated that physiological activities in Allium microdictyon is more limited from high VPD conditions.

• Journal of Environmental Science International
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• v.28 no.12
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• pp.1111-1121
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• 2019

The purpose of this study is to analyze the effect of perceived walking environment around neighborhood on satisfaction for old adults in Daegu. The study was conducted using 407 questionnaires were collected through the survey. The walking environment was categorized into accessibility to neighborhood walking facilities and walking environment around path. Regarding perception of walking accessibility, access to 'public transit stops' and to 'medical facilities' was relatively high. For walking environment, 'pavement condition', 'continuity of sidewalk', and 'slope of sidewalk' were rated relatively high. Multiple regression analysis after factor analysis of walking environment variables showed that religious and convenient facilities, park and leisure facilities, and medical and welfare facilities had a significant effect on satisfaction in walking accessibility. For walking environment the convenience for walking, safety for walking, and amenities for walking had a significant effect on satisfaction. The findings from this study can be used for improving the walking environment for old adults.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.640-648
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• 2009

Recently the truction of coastal reclaimation work has been extensively implemented in Korea. The Sondo New City is being established on the reclaimed land from the sea, construction companies of metro construction are planing to pull-out the sheet pile for saving the construction cost. In the case of soft marine clay, it is very difficult to pull-out the sheet pile by using the hydraulic hammer difficult. Therefore, the man of the field must be aware of vibration effect to the ground and the structure. For understanding the vibration effect to the ground during subway construction, the model was formulated with 1/25 braced-cut for subway construction. Scott and Iai(1989) proposed the law of the similarity for other experimental conditions. The laboratory model test was conducted under the vibration condition of sheet pile pulling out. The settlement on the ground surface was measured during the shaking table test. The pore water pressure was also monitored in the upper, middle, and lower layers of soil. The field settlement level and the pore water pressure can be predicted by using the results of the laboratory shaking table test.

• Computers and Concrete
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• v.33 no.5
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• pp.559-572
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• 2024

Problems of under-sized dams (small dams with large basin area) could get worse under the global warming condition. This study evaluates the possible change of these problems with the Namgang Dam, an under-sized dam in Korea. For this purpose, first, this study simulates the dam inflow data using a rainfall-runoff model, which are then used as input for the reservoir operation. As a result, daily dam storage, dam release, and dam water supply are derived and compared for both past observed period (1973~2022) and future simulated period (2006~2099) based on the global warming scenarios. Summarizing the results are as follows. First, the inflow rate in the future is expected to be increased significantly. The maximum inflow could be twice of that observed in the past. As a result, it is also expected that the frequency of the water level reaching the high level is increasing. Also, the amount and frequency of dam release are to be increased in the future period. More seriously, this increase is expected to be concentrated on rather extreme cases with large dam release volume. Simply, the condition for flood protection in the downstream of the Namgang Dam is becoming worse and worse. Ironically, the severity of water shortage problem is also expected to become much worse. As the most extreme case, the frequency of no water supply was zero in the observed period, but in the future period, it becomes once every five years. Both the maximum consecutive shortage days and the total shortage volume are expected to become more than twice in the future period. To prevent or mitigate this coming problem of an under-sized dam, the only countermeasure at this moment seems to be its redevelopment. Simply a bigger dam with larger dam reservoir can handle this adverse effect more easily.

• Journal of the Korean Geotechnical Society
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• v.28 no.8
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• pp.21-29
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• 2012

At-rest lateral stress coefficient that is used for the evaluation of geotechnical structures such as foundations and retaining walls plays a significant role in the analysis and design, as a state variable of in-situ stress condition. In the widely applied Jaky's Ko equation stress condition can be inferred from the internal friction angle obtainable from the laboratory experimentation whereas the eguation mares it challenging to evaluate the influences and criteria of particle characteristics which is essential for the application of friction angles in practices. Thus, this study experimentally explored the behaviors of Ko depending on the relative density, particle shape, and surface roughness effect during a range of loading stages. The Ko values of Jumumjin sand, glass beads, and etched glass beads were measured using a customized Ko device housing strain gauges during loading-unloading-reloading steps, and the effect of dominant factors on Ko is analyzed. Results show that the high Ko prevails for both round and angular specimens with low relative density and the surface roughness has a nominal effect. The angular particles exhibit low Ko for specimens with similar relative density. The characteristics of relevance between Ko and friction angles with varying relative density are also investigated based on the experimental results using empirical correlations and previously reported values.