• Journal of Welding and Joining
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• v.33 no.3
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• pp.62-67
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• 2015

A very large shell-structure built in shipyards like ship hulls or offshore structures are joined by welding through full process. As the welding contains a high thermal cycle at a local area, the welded structures should be distorted unavoidably. Because a distorted ship block should be revised to the designed value before the next stage, the ability to predict and to control the weld distortion is an accuracy level of the yard itself. Despite the ship block size, several present thermal distortion methodologies can deal those sizes, but it is a different story to deal full ship size model. Even a fully constructed ship hull not remaining any welding can have an accuracy issue like outfitting installation problems. Any present thermal distortion methodology cannot accept this size for its recommended element size and the number. The ordinary welding breadth at erection stage is about 20~40 mm. It can hardly be a good choice to make finite element model of these sizes considering human effort and computational environment. The finite element model for structure analysis of a ship hull is prepared at front-end engineering design stage which is the first process of the project. The element size of the model is as fine as the longitudinal space, and it is not proper to obtain a weld distortion at the erection stage. In this study, a methodology is suggested that a weldment can be shrunk at original place instead of using structural finite element model. We cut the original shell elements at erection weld-line and put truss elements between the edges of cut elements for weld shrinkage. Additional truss elements are used to facsimile transverse weld shrinkage which cannot be from the weld-line truss element shrink. They attach to weld-line truss element like twigs from barks. The capacity of developed elements is verified through an accuracy check of erection process of a container vessel at the apt. hull. It can be a useful tool for verifying a centering accuracy after renew and for block-separating planning considering accuracy.

• Journal of The Korean Society of Clinical Toxicology
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• v.7 no.1
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• pp.10-18
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• 2009

Purpose: Carbon Monoxide Poisoning is an important medical emergency in Korea, but the factors leading to its serious manifestation are not well studied. Methods: We conducted a 5-year retrospective study of 98 carbon monoxide poisoned patients who visited the emergency departments of the Medical Center between December 2004 and March 2009. We categorized the patients into those exhibiting only local symptoms (group 1) and those showing systemic symptoms and complications (group 2). We compared the general characteristics as well as the clinical and laboratory findings between both groups. Results: The male to female ratio was 1.18. The most common systemic symptom was a mental change (43.9%), while the most common complication was rhabdomyolysis (31.6%). Poisoned area closed private room in group 2 were 23 (41.8%) cases and burning region in group 2 were 16(29.1%) cases (p=0.956). Individuals who were accidentally poisoned comprised of 43 (78.2%) cases while those that attempted suicidal poisoning comprised 12 (21.8%) cases (p=0.016). The most common symptom at arrival was mental change 33 (60.0%) cases in group 2. The mean time exposed to carbon monoxide was 43$\pm$3.97 hours in group 1 and 55$\pm$10.11 in group 2 (p=0.012). The patient's age, context of poisoning, symptom at arrival, and time exposed to the poison were found to be significant risk factors for complications by logistic regression analysis. Conclusion: Carbon monoxide poisoning is an emergency medical condition and the risk factors involved in the development of serious complications must be evaluated.

• Earthquakes and Structures
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• v.16 no.4
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• pp.501-512
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• 2019

In this study, seismic vulnerability assessment and seismic isolation retrofit of Bayburt Yakutiye Mosque is investigated. Bayburt Yakutiye Mosque was built in the early 19th century at about 30-meter distance to Coruh river in the center of Bayburt in Turkey. The walls of historical masonry structure were built with regional white and yellow stones and the domes of the mosque was built with masonry bricks. This study is completed in four basic phases. In first phase, experimental determination of the regional white stone used in the historical structure are investigated to determine mechanical properties as modulus of elasticity, poison ratio and compression strengths etc. The required information of the other materials such as masonry brick and the regional yellow stone are obtained from literature studies. In the second phase, three dimensional finite element model (FEM) of the historical masonry structure is prepared with 4738 shell elements and 24789 solid elements in SAP2000 software. In third phase, the vulnerability assessment of the historical mosque is researched under seismic loading such as Erzincan (13 March 1992), Kocaeli (17 August 1999) and Van (23 November 2011) earthquakes. In this phase, the locations where damage can occur are determined. In the final phase, rubber base isolators for seismic isolation retrofit is used in the macro model of historical masonry mosque to prevent the damage risk. The results of all analyses are comparatively evaluated in details and presented in tables and graphs. The results show that the application of rubber base isolators can prevent to occur the destructive effect of earthquakes.

• Journal of agricultural medicine and community health
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• v.9 no.1
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• pp.46-55
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• 1984

The socio-psychiatric study and personality analysis by Minnesota Multiphasic Personality Inventory on attempted suicides with drug intoxication in Seonsan-Gun and Cheongdo-Gun of Kyoungsang buk-Do was attempted to identify overall picture of attempted suicides and to detect some characteristics of personality. The total of 93 suicide attempted cases which were brought to the local clinics for the past 3 years from February, 1981 to February,1984 were sampled among them. The socio-psychiatric study and MMPI were performed with 45 attempters possible to be interviewed. The personalities of a group which answered "Still have the desire occasionally" or "Don't know about the present attitude toward suicide was compared with those of the other group who answered "Will not do it agagin". The results were as follows; 1) The sex ratio of the total attempters (93 cases) were 138.5. The highest rate by age group was found in the 3rd decade to be 27 cases. On the other hand, the sex ratio of interviewed cases were 136.8 and the highest rate was found in the age group of 50-59. 2) For the common characteristics of majority other than sex, 55.7% of cases were graduated primary school, and 62.2% were engaged in agriculture. 3) Except the fact that more of the attempted suicides happened during summer, there were no seasonal variation among other seasons. 4) The places selected for the attempted suicides were the houses in majority of cases (98%). Most of cases (53.3%) were found immediately after the attempt and 24.4% within one hour. For the poison taken, 86.7 took a sort of herbicides or insecticides, 55.6% were admitted to local clinics for only one day and 20% for two days. 5) The most common precipitating factors of the attempted suicides were family trouble and financial poverty. 6) The psychodynamic motives of the attempters were impulsive hostility(35.6%), abandonment(33.3%), guilt feeling (11.1%), manipulation and attention seeking (8.9%) and others. 7) In regard to their present attitude toward suicide, 29 cases (64.4%) expressed that they would never do such an act again, 37.8% of cases expressed that they really wanted to die at the time when they attempted. 8) The Psychopathic deviate, Paranoia, Depression, Schizophrenia scores were significantly higher in the attempters group who answered "Don't know" or "Possibly" for the question of "Will you attempt suicide again?" Than the group who answered" will not do it again".

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.63-66
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• 2009

Purpose: ACR (American College of Radiology) offers variable parameters to PET/CT quality control by using ACR Phantom. ACR Phantom was made to evaluate parameters which are uniformity, attenuation, scatter, contrast and resolution. Manual analysis method wasn't good for the use of QC because values of parameter were changed as it may user and it takes long time to analysis. Ki-Chun Lim, a nuclear scientist in AMC, developed program that automatically analysis values of parameter by using ACR Phantom to overcome above problems. In this study, we evaluated automatic analysis program's usability, through the comparing SUV of each method, reproducibility of SUV when repeated analysis and the time required. Materials and Methods: Using Flangeless Esser PET Phantom, the ideal ratio of 4 : 1 hot cylinder and BKG but it actually showed a ratio of 3.89 to 1 hot cylinder and BKG. SIEMENS Biograph True Point 40 was used in this study. We obtained images using ACR phantom at Fusion WB PET Scan condition (2 min/bed) and 120 kV, 100 mAs CT condition. Using True X method, 3 iterations, 14 subsets, Gaussian filter, FWHM 4 mm and Zoom Factor 1.0, $168{\times}168$ image size. We obtained Max. & Min. SUV and SUV Mean values at Cylinder (8, 12, 16, 25 mm, Air, Bone, Water, BKG) by automatic program and obtained SUV by manual method. After that, we compared manual and automatic method. we estimate the time required from opened the image data to final work sheet was completed. Results: Automatic program always showed same result and same the time required. At 8, 12, 16 and 25 m cylinder, manual method showed 6.69, 3.46, 2.59, 1.24 CV values. The larger cylinder size became, the smaller CV became. In manual method, bone, air, water's CV were over 9.9 except BKG (2.32). Obtained CV of Mean SUV showed BKG was low (0.85) and bone was high (7.52). The time required was 45 second, 882 second respectably. Conclusions: As a result of difference automatic method and manual method, automatic method showed always same result, manual method showed that the smaller hot cylinders became, the lager CV became. Hot cylinders mean region size, the smaller hot cylinder size becomes we had some trouble in doing ROI poison setting. And it means increase in variation of SUV. The Study showed the time required of automatic method was shorten then manual method.

• Journal of Food Hygiene and Safety
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• v.37 no.3
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• pp.159-165
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• 2022

In this study, heavy metals (lead, cadmium, and mercury) and shellfish poisoning toxins (diarrhetic shellfish poisoning toxins, amnesic shellfish poisoning toxins) were investigated in a total of 104 shellfishes. According to the analysis of heavy metals, lead (Pb) was detected in the range of 0.0177-0.5709 mg/kg, cadmium (Cd) was detected in the range of 0.0226-1.4602 mg/kg, and mercury (Hg) was detected in the range of 0.0015-0.0327 mg/kg. Levels of Pb, Cd, and Hg were acceptable by Korean standards. Okadaic acid (OA) and dinophysistoxin-1 (DTX-1) were investigated for monitoring of diarrhetic shellfish poisoning toxins and OA and DTX-1 were not detected. As a result of monitoring of amnesic shellfish poisoning toxins, domoic acid was detected in 5 of 104 samples and detection ratio was 4.8%. The detection period was found as follows; 1 case in January, 1 case in February, 1 case in May, 2 cases in September. These showed that continuous monitoring for the management of shellfish poisoning toxins and heavy metals is required. In addition, this study can be used as reference data to strengthen managing heavy metals in fishery products.

• Journal of Sericultural and Entomological Science
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• v.20 no.2
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• pp.26-31
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• 1978

The objective of the present study was to investigate the effect of nicotine-contaminated mulberry-leaf, which was grown in the vicinity of tobacco drying plant (TDP), on cocoon crop. Mulberry-leaf harvested from the field at Sericultural Experiment Station (SES), Suweon, Korea, was used as control, supposedly nicotine-free leaf. Leaf harvested from the field in the distances of 30-50m, 300-400m and 700-800m from TDP was fed during the whole larval stage of the silkworm at. SES. The effect of leaf in each treatment level on the quantitative characters of the silkworm was summarized as follows; 1. Larval duration from 4th instar on was significantly longer in the TDP-leaf treatments than for the control. 2. Duration of matured silkworm appearance became longer as the distance of the mulberry-field from TDP got shorter, because the larval duration and growth of the silkworm were not uniform in the TDP-leaf treatments. 3. Mortality rates during the late larval, cocoon spinning, and pupal stages were highest for the 30-50m leaf, especially mortality rates during the late larval and pupal stage were serious. 4. Pupation rate was lowest for the 30-50m leaf and those for the 300-400m and the 700-800m leaf were not significantly different from that of the control. 5. Nicotine damage to cocoon weight and cocoon shell weight was significant in each TDP-leaf level. Cocoon shell ratio was reduced at the same extent in each level, compared with the control. 6. The ratio among cocoon-classes was significantly different between treatments, compared with best-cocoon ratio of 87.1% for the control. Cocoons were not uniform for the 30-50m leaf, and those for the 300-400m and the 700-800m leaf were as almost uniform as those for the control. 7. Loss of fresh cocoon yield became greater as the distance of the mulberry-field from the TDP-got shorter. In conclusion, the critical distance of mulberry-field, which influences larval health, cocoon quality and yield, appeared to be 800m from the TDP. Such other factors as wind direction and topographic location may be involved in the critical distance. 8. From the present experiment, we could obtain only the effect of nicotine on the silkworm through digestive system, since the silkworm was raised at SES in Suweon. If the silkworm.. were raised in the vicinity of the TDP, poison effect of nicotine on the silkworm could beo expected through exoskeleton and tracheal system as well as through digestive system.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.87-96
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• 2004

Studies were conducted to select the candidate buffer material for a high-level waste (HLW) repository in Korea. This paper presents the hydraulic properties, the swelling properties, the thermal properties, and the mechanical properties as well as the radionuclide release-retarding capacity of Kyungju bentonite as part of those studies. Experimental results showed that the hydraulic conductivities of the compacted bentonite were very low and less than $10^{-11}$m/s. The values decreased with increasing the dry density of the compacted bentonite. The swelling pressures were in the range of 0.66 MPa to 14.4 ㎫ and they increased with increasing the dry density. The thermal conductivities were in the range of 0.80 ㎉/m $h^{\circ}C$ to 1.52 ㎉/m $h^{\circ}C$. The unconfined compressive strength, Young's modulus and Poison's ratio showed the range of 0.55 ㎫ to 8.83 ㎫, 59 ㎫ to 1275 ㎫, and 0.05 to 0.20, respectively, when the dry densities of the compacted bentonite were 1.4 Ms/㎥ to 1.8 Mg/㎥. The diffusion coefficients in the compacted bentonite were measured under an oxidizing condition. The values were $1.7{\times}10^{-10}$m^2$/s to 3.4{\times}10^{-10}$m^2$/s for electrically neutral tritium (H-3), 8.6{\times}10^{-14}$m^2$/s to 1.3{\times}10^{-12}$m^2$/s for cations (Cs, Sr, Ni), 1.2{\times}10^{-11}$m^2$/s to 9.5{\times}10^{-11}$m^2$/s for anions (I, Tc), and 3.0{\times}10^{-14} $m^2$/s to 1.8{\times}10^{-13}$m^2$/s $for actinides (U, Am), when tile dry densities were in the range of 1.2 Mg/㎥ to 1.8 Mg/㎥. The obtained results will be used in assessing the barrier properties of Kyungju bentonite as a buffer material of a repository in Korea.n Korea.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6C
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• pp.395-406
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• 2006

Drilled shafts are a common foundation solution for large concentrated loads. Such piles are generally constructed by drilling through softer soils into rock and the section of the shaft which is drilled through rock contributes most of the load bearing capacity. Drilled shafts derive their bearing capacity from both shaft and base resistance components. The length and diameter of the rock socket must be sufficient to carry the loads imposed on the pile safely without excessive settlements. The base resistance component can contribute significantly to the ultimate capacity of the pile. However, the shaft resistance is typically mobilized at considerably smaller pile movements than that of the base. In addition, the base response can be adversely affected by any debris that is left in the bottom of the socket. The reliability of base response therefore depends on the use of a construction and inspection technique which leaves the socket free of debris. This may be difficult and costly to achieve, particularly in deep sockets, which are often drilled under water or drilling slurry. As a consequence of these factors, shaft resistance generally dominates pile performance at working loads. The efforts to improve the prediction of drilled shaft performance are therefore primarily concerned with the complex mechanisms of shaft resistance development. The shaft resistance only is concerned in this study. The nature of the interface between the concrete pile shaft and the surrounding rock is critically important to the performance of the pile, and is heavily influenced by the construction practices. In this study, the influences of asperity characteristics such as the heights and angles, the strength characteristics and elastic constants of surrounding rock masses and the depth and length of rock socket, et. al. on the shaft resistance of drilled shafts are investigated from elasto-plastic analyses( FLAC). Through the parametric studies, among the parameters, the vertical stress on the top layer of socket, the height of asperity and cohesion and poison's ratio of rock masses are major influence factors on the unit peak shaft resistance.