• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
• /
• 2002.10a
• /
• pp.45-50
• /
• 2002

This study presents a modeling method to predict fate of resuspended sediment in the development of deep-sea mineral resources. Resuspended deep-sea sediment during the development is considered a major environmental problem. In order to quantitatively analyze the resuspended sediment in the water column, particle size distribution (PSD) is considered an important factor. The model developed here includes PSD and coagulation process, as well as sedimentation process. Using the model, basic simulation was performed under representative environmental setting. The simulation showed the dynamics of change of particle size distribution for 50 m depth of water column up to 10 days of simulation time. Coagulation seemed an important factor in the fate of resuspended deep-sea sediment.

• Journal of the Korea Safety Management & Science
• /
• v.2 no.2
• /
• pp.117-126
• /
• 2000

Recently micro deep hole drilling is required in the whole industry. However, micro deep hole drilling has still much difficulty because of the lack of drill rigidity and the interruption of chip. We treated a micro deep hole(diameter 0.35mm, depth 3mm) used in a connector jack pin. Therefore, a surface roughness is very important. In this paper, we studied on the variation of the surface roughness for cutting conditions during micro deep hole drilling of Be-Cu material. Most of all, we tried to drill on CNC for the realization of automatization.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.31 no.2
• /
• pp.242-248
• /
• 1986

To study the effect of cold water irrigation at the reproductive growth stage of rice plants on several growth characters related to source and sink and nutrient uptake, the present experiment was carried out under the different conditions of water temperature and water depth. Deep irrigation with normal temperature water increased culm length, panicle length and panicle exsertion but with cold water resulted adversely. Most sensi-tive response in 5 cm water-depth appeared at reduction division stage and in 20 cm depth at panicle formation stage. Secondary branches and spikelets were increased in number by deep irrigation with normal temperature water, but decreased and degenerated by deep irrigation with cold water at panicle formation stage resulting in high spikelet sterility and low grain filling. Deep irrigation with normal temperature water increased the contents of total nitrogen, phosphate, potassium and silicate in leaf blades, branches and chaff. However, cold water irrigation reduced the uptake of phosphate, potassium and silicate except nitrogen particularly in deep irrigation. Ratios of phosphate, potassium and silicate to total nitrogen content were decreased by cold water irrigation. Branches seemed to have higher requirements for phosphate, potassium and silicate than leaf blades and chaff. Silicate-to-total nitrogen ratio in leaf blades, branches and chaff had significant correlations with yield showing closer relationship between yield and the ratio of silicate to total nitrogen in branches in particu-lar.

• Journal of Navigation and Port Research
• /
• v.42 no.1
• /
• pp.9-16
• /
• 2018

The development of limited petroleum resources for use with mankind inevitably explores and seeks to develop oil fields in the deep sea area, under the rise of the oil prices market situation. The use of Oceanic Thermal Energy Conversion (OTEC) technology, which operates the power generation facility using the temperature differences between the deep water and the surface water, is progressing actively as a trend to follow. In this study, the application of the Discharged Thermal Energy Conversion (DTEC) was designed and analyzed under the condition that the supply condition of seawater used in the FPSO installed in the deep sea area is changed up to 400m depth. In this case, it was confirmed that the design of the system that can generate more electric power according to the depth of water is confirmed, by thus applying the DTEC system by taking the cooling water at a deeper water depth than the existing design water depth. The FPSO considers the similarity of the OTEC power generation facilities, and will apply the DTEC system to FPSO in the deep sea area to accumulate technology and the conversion to further utilize the OTEC power generation facilities after the end of life cycle of oil production, which could be a solution to two important issues, namely, resource development and sustainable development.

• Journal of Soil and Groundwater Environment
• /
• v.7 no.3
• /
• pp.71-77
• /
• 2002

This research was carried out from 2001. 4 until 2001. 5 in order to examine the level of soil contamination in the vicinity of Nanjido. The sampling was done at near the Nanjido soil. At the each sampling site we did the sampling at different depth- surface(0~15cm deep), 1m deep, 2m deep, 3m deep. The contamination of Cd, Cu, Pb, As, $Cr^{+6}$, and Hg were tasted and analysed by spectra AA. The examination showed that the average concentration level of the entire sampled soil was Cd, 0.229mg/kg, Cu 8.349mg/kg, Pb : 11.083mg/kg, As : 0.298mg/kg, $Cr^{+6}$ : 0.124mg/kg, and Hg : 0.134mg/kg. The concentration level of at the depth of 0-l5cm, came out to be Cd : 0.305mg/kg, Cu : 8.464mg/kg, Pb : 11 383mg/kg, As : 0.128mg/kg, $Cr^{+6}$ : 0.153mg/kg, and Hg : 0.092mg/kg. It shows that in the cases of Cd and C $r^{+6}$ the average concentration level of the whole sampled soil was about 80% of that of 0-l5cm depth. And as for Hg and As. the average concentration level of the entire sampled soil came out to be approximately twice as high as the sample soil from the depth surface, As for Cu and Pb, there was not much difference between the entire samples average concentration level and the concentration level of surface. It was hard to find much relationship between the depth of each site where sampling was done and the level of concentration, the concentration level of Pb and Cu at the sampling site C and E was quite high, which suggests that it has been affected by the polluted the hyang-dong stream and fill random up waste.

• Magazine of the Korea Concrete Institute
• /
• v.11 no.1
• /
• pp.191-200
• /
• 1999

The shear behavior of simply supported reinforced concrete deep beams subject to concentrated loads has been scrutinized experimentally to verify the influence of the structural parameters such as concrete strength, shear span-depth ratio, and web reinforcements. A total of 42 reinforced concrete deep beams with compressive strengths of 250 kg/$cm^2$ and 500 kg/$cm^2$ has been tested at the laboratory under one or two-point top loading. The shear span-depth ratio have been taken as three types of 0.4, 0.8 and 1.2, and the horizontal and vertical shear reinforcements ratio, ranging from 0.0 to 0.57 percent respectively. In the tests, the effects of the shear span-depth ratio, concrete strength and web reinforcements on the shear strength and crack initiation and propagation have been carefully checked and analyzed. From the tests, it has been observed that the failures of all specimens were due to shear and the shear behaviors of specimens were greatly affected by inclined cracks from the load application points to the supports in shear span. The load bearing capacities have changed significantly depending on the shear span ratio, and the efficiency of horizontal shear reinforcements were increased as the shear span-depth ratio decreased. The test results have been analyzed and compared with the formulas proposed by previous researchers and the design equation from the code. While the shear strengths obtained from the tests showed around 1.4 and 1.9 times higher than the values calculated by CIRIA guide and the domestic code, they were closely coincident with the formulas given by de Paiva's equation.

• Ocean and Polar Research
• /
• v.24 no.2
• /
• pp.153-166
• /
• 2002

Particle fluxes were measured by using time-series sediment traps in the Bransfield Strait from December 27th, 1999 to December 26th, 2000. Total mass fluxes showed distinct seasonal variations with high fluxes in the austral summer and low fluxes in the austral winter at a 678m water depth in the eastern Bransfield Strait, while they were high only in January and fairly low in other months at a 960m water depth in the central Bransfield Strait. The reason that total mass fluxes occurred only in January at a 960m water depth in the central Bransfield Strait seems to be the strong current in the surface waters, which leads to a substantial amount of terrestrial materials and locally produced organic matter being advected away from the mooring site. Total mass fluxes were very high from January to October at a 1678m water depth in the eastern Bransfield Strait, while they were high only in January and February at a 1860m water depth in the central Bransfield Strait. The fact that total mass fluxes were higher at the deep water in the both sites than at the intermediate water depth may reflect that a substantial amount of terrestrial and organic materials are laterally transported by strong tidal current from the shallow environments to the deep basins.

• The Journal of Advanced Prosthodontics
• /
• v.7 no.2
• /
• pp.115-121
• /
• 2015

PURPOSE. This study aimed to evaluate the effect of implant thread depth on primary stability in low density bone. MATERIALS AND METHODS. The insertion torque was measured by inserting Ti implants with different thread depths into solid rigid polyurethane blocks (Sawbones) with three different bone densities ($0.16g/cm^3$, $0.24g/cm^3$, and $0.32g/cm^3$). The insertion torque value was evaluated with a surgical engine. The static compressive strength was measured with a universal testing machine (UTM) and the Ti implants were aligned at $30^{\circ}$ against the loading direction of the UTM. After the static compressive strength test, the Ti implants were analyzed with a Measurescope. RESULTS. The Ti implants with deeper thread depth showed statistically higher mean insertion torque values (P<.001). Groups A and group B had similar maximum static compressive strengths, as did groups C and D (P>.05). After the static compressive strength, the thread shape of the Ti implants with deeper thread depth did not show any breakage but did show deformation of the implant body and abutment. CONCLUSION. The implants with deeper thread depth had higher mean insertion torque values but not lower compressive strength. The deep threads had a mechanical stability. Implants with deeper thread depth may increase the primary stability in areas of poor quality bone without decreasing mechanical strength.

• Journal of The Korea Institute of Healthcare Architecture
• /
• v.15 no.1
• /
• pp.23-32
• /
• 2009

Among welfare facilities for the elderly, necessity for the elderly welfare with diverse advantages is rising in the Small-scale Elderly Care Facilities. The government is expecting great demand in the future. However, current the Facilities lack construction plans that consider characteristics of the elderly. Accordingly, 14 case facilities located in JeollaNamdo and Gwangju were selected to comprehensively analyze the circulation of seniors at care facilities by computing spatial depth and visible area variables. As a result of this study, average spatial depth of bathroom, resting room, physical therapy room and dining hall that seniors frequently get in contact with was found to be deep, but visible area appropriate for the function of space was not available. It showed that the circulation for the elderly was deep spatially and long physically, and the spatial rank along circulation which is perceived visually by the admitted the elderly was clear, thus, providing them abundant visual experience supported by high openness as they move from private space to public space. The obtained visibility, however, was observed not to be matched with the function of each space. Since the Small-scale Elderly Care Facilities require various spaces within small surface area, actual functions of each space must be taken into consideration with hierarchical space organization to obtain an environment that stimulates senses such as vision and hearing. In addition, since the circulation of seniors using facilities must consider aging characteristics and delicate care on spatial depth and physical distances, in-depth studies on planning of the circulation in care facilities are deemed necessary.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.3
• /
• pp.389-395
• /
• 2022

Because of improvement of deep learning techniques, deep learning using computer vision such as classification, detection and segmentation has also been used widely at many fields. Expecially, automatic driving is one of the major fields that applies computer vision systems. Also there are a lot of works and researches to combine multiple tasks in a single network. In this study, we propose the network that predicts the individual depth of pedestrians and vehicles. Proposed model is constructed based on YOLOv3 for object detection and Monodepth for depth estimation, and it process object detection and depth estimation consequently using encoder and decoder based on hard parameter sharing. We also used attention module to improve the accuracy of both object detection and depth estimation. Depth is predicted with monocular image, and is trained using self-supervised training method.