• The Journal of Engineering Geology
• /
• v.28 no.2
• /
• pp.277-295
• /
• 2018

As it has become difficult to secure new water resources through dam construction due to the critical social public opinions on dam construction from 10 years ago, it is necessary to review the existing water resources through the review of existing dams. Accordingly, access methods, such as planning, construction and management, were carried out using technologies already accumulated in relation to the repair and reinforcement of the dam. As a result of the repair and reinforcement, permeation grouting has been performed in many dams, but the establishment of the technology is insufficient so far, and the published paper at home and abroad is extremely rare. In this thesis, low-pressure penetration and grouting reinforcement technologies for the YC dam are analyzed in detail. As a result, penetration grouting has shown that it can be effectively applied to the improvement in the constallability of the core fill-like a YC dam. In addition, the technical details of the experience-proven penetration grouting are given in relation to the injection criteria. It is deemed that the specific analysis data of the Fill Dam penetration grouting technology through this study can be used as useful data for strengthening the repair of Fill Dam and reservoir.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.6
• /
• pp.748-753
• /
• 2000

Objectives : A 10-year retrospective clinical study was undertaken to determine the differences between two groups according to age at presentation(group A, under 50 ; B, over 50). Methods : We analyzed 468 cases with chronic subdural hematoma admitted to the department of neurosurgery in our hospital from January 1987 to December 1996. The patients were divided into two groups according to age at presentation(group A, under 50 ; B, over 50). Results : 1) The number of group A was 126 cases(26.9%) and that of group B was 342 cases(73.1%), respectively. Males were more frequently involved than females in each group. 2) There noted a history of head trauma in 88.9% of group A and 92.4% of group B. Forty-nine patients(38.9%) of group A and 103 cases(30.1%) of group B revealed a history of alcoholism. 3) Group A patients presented with symptoms of increased intracranial pressure such as headache(75.% ), nausea and vomiting(68.0%). However, Group B patients had more frequent mental changes(84.0%) and focal neurological deficits such as hemiparesis(76.5%). 4) Onset of symptom and its duration was shorter in group A than group B. 5) Six patients among 441 cases(1.4%) treated with burr hole drainage and two patients of 27 cases(5.4%) with craniotomy died, and all of these were group B patients. The two cases among six patients with burr hole drainage developed huge intracerebral hemorrhage and brain stem hemorrhage, respectively. Conclusion : In treating patients with chronic subdural hematoma, distinguishing between two age groups is quite helpful to determine treatment strategies.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.35 no.1
• /
• pp.8-14
• /
• 2002

Quality variation of jar packing of Chanran-Jeotgal produced by improved process and conventional process were investigated during storage at 10, 20, and $30^{\circ}C$, respectively. The increasing rate of pH, volatile basic nitrogen (VBN), $CO_{2}$, and viable cell counts of Chanran-Jeotgal produced by improved process was slower than that of conventional process at all storage temperature. Also the result of sensory evaluation indicate that the production of Changran-Jeotgal by improved process may extend the shelf·life of jar packing Chanuan-Jeotgal. From above results, relationship between quality parameters was concluded. In case of Changran-Jeotgal in a jar, pressure, pH, L-value, VBN and sensory score were highly correlated. Therefore, these parameters are expected to use as shelf-life indication.

• Journal of Navigation and Port Research
• /
• v.32 no.8
• /
• pp.577-582
• /
• 2008

In order to ascertain the effect of ship's speeds, in maneuver under the condition of strong cross current in the breakwater channel of Busan port, this paper is to deal with the analyses of vessel proximity measures, vessel controllability measures, and ship handlers' subjective evaluation measures of simulated maneuvers, which were carried out by 76 ship handlers who conned Panamax bulk carrier of 60,000 DWT, The set and drift of current are southwesterly and 2 knots. The speeds of the model ship are 5 knots & 10 knots respectively. The followings are concluded. ${(1)}$ In the approaches of the breakwater of Busan port, ship handlers psychologically tend not to give the drift angle of more than $10^{\circ}$ bemuse ship's head points out of the entrance. ${(2)}$ Ship handlers' subjective evaluation, vessel proximity and controllability measures are relatively larger under the speed of 5 knots than under that of 10 knots. due to direct pressure of strong current. ${(3)}$ A single index of controllability measures was suggested, by removing their units.

• Journal of the Korean Geotechnical Society
• /
• v.28 no.5
• /
• pp.27-39
• /
• 2012

In this paper, a series of centrifuge tests were performed to evaluate the seepage characteristic of reinforced embankment. The centrifuge models simulated an actual embankment reinforced by enlargement of levee cross-section. The centrifuge models have the same conditions except the locations of enlargement with low permeable material : water-side and land-side. In addition, the prototype embankment is constructed on low permeable clay layer. In the case of water-side reinforcement, the reinforced zone makes water head down and the saturated zone of embankment propagates slowly. In the case of land-side reinforcement embankment, the saturated zone enlarged relatively faster but the amount of exit water at land-side toe was very small because of the land-side reinforcement zone. The low permeable clay foundation layer was being continuously saturated by the inflow from the embankment as well as the uplift flow from the permeable layer induced by the excess pore water pressure.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.36 no.10
• /
• pp.1115-1130
• /
• 2012

In nuclear power plants, the reactor pressure vessel (RPV) upper head control rod drive mechanism (CRDM) penetration nozzles are fabricated using J-groove weld geometry. Recently, the incidences of cracking in Alloy 600 CRDM nozzles and their associated welds have increased significantly. The cracking mechanism has been attributed to primary water stress corrosion cracking (PWSCC), and it has been shown to be driven by welding residual stresses and operational stresses in the weld region. The weld-induced residual stress is the main factor contributing to crack growth. Therefore, an exact estimation of the residual stress is important for ensuring reliable operation. This study presents the residual stress computation performed for an RPV CRDM penetration nozzle in Korea. Based on two and three dimensional finite element analyses, the effect of welding variables on the residual stress variation is estimated for sensitivity analysis.

• Fashion & Textile Research Journal
• /
• v.1 no.4
• /
• pp.376-386
• /
• 1999

The purpose of this study was to determine the physiological responses and the Subjective sensations of the human subjects when 10 human subjects(5 males and 5 females) were tested with selected ensembles, including the uniforms of students, industrial and bank workers. For the study, garment material and design were selected, which was mostly used in Taegu area by the survey. Thermal manikin and the human subject tests were performed. The results were as follows: 1. There was no significant difference among skin temperature of head by season and among that of breast and back by all variables, however, there was a significant difference among that of belly by gender and that of thigh and shank by season. In addition, there was no significant difference among rectal temperature by gender and season, but there was a significant difference by uniform. 2. Mean skin temperature of male subjects was significantly higher than that of female subjects. Specially in lower environmental condition, the difference got larger. 3. There was a significant difference among purse rate of subjects by uniform, but there was no significant difference among those by gender and season. There were no significant difference among maximum and minimum blood pressure by gender, uniform, and season. 4. There was a significant difference in temperature of chest among gender and uniform, and there was no significant difference in temperature of back by season. In addition, There was a significant difference in humidity of back by uniform and season but there were no significant difference in that by gender. 5. There was a significant difference in humidity sensation by gender, comfort sensation by uniform and season, but there was no significant difference thermal sensation by uniform and season. 6. For the result of regression analysis, we got the regression equations as follows: Clo=1.810 Thickness+0.525, Clo=0.475 weight+0.863.

• Tunnel and Underground Space
• /
• v.30 no.5
• /
• pp.496-507
• /
• 2020

A prediction of the performance of EPB TBM is significant for improving the constructability of tunnels. Thus, various attempts to simulate TBM excavation by the numerical method have been made until these days. In this paper, to evaluate the performance of TBM with different operating conditions, a parametric study was carried out using coupled discrete element method (DEM) and finite difference method (FDM) EPB TBM driving model. The analysis was conducted by changing the penetration rate (0.5 and 1.0 mm/sec) and the rotational speed of screw conveyor (5, 15, and 25 rpm) while the rotation velocity of the cutter head kept constant at 2 rpm. The torque, thrust force, chamber pressure, and discharging with different TBM operating conditions were compared. The result of parametric study shows that the optimum driving condition can be determined by the coupled DEM-FDM numerical model.

• Journal of Trauma and Injury
• /
• v.20 no.2
• /
• pp.144-148
• /
• 2007

Purpose: The management of hemorrhagic shock is critical for trauma patients. To assess hemorrhagic shock, the clinician commonly uses a change in positional blood pressure, the shock index, an estimate of the diameter of inferior vena cava based on sonography, and an evaluation of hypoperfusion complex shown on a CT scan. To add the finding for the hypoperfusion complex, the 'halo sign' was introduced recently. To our knowledge, this 'halo sign' has not been evaluated for its clinical usefulness, so we designed this study to evaluate its usefulness and to find the useful CT signs for hypoperfusion complex. Methods: The study was done from January 2007 to May 2007. All medical records and CT images of 124 patients with trauma were reviewed, of which 103 patients were included. Exclusion criteria was as follows: 1) age < 15 year old and 2) head trauma score of AIS ${\geq}$ 5. Results: The value of kappa, to assess the inter-observer agreement, was 0.51 (p < 0.001). The variables of the halo-sign-positive group were statistically different from those of the halo-sign-negative group. The rate of transfusion for the halo-sign-positive group was about 10 times higher than that of the halo-sign-negative group and the rate of mortality was about 6 times higher. Conclusion: In the setting of trauma, early abdominal CT can show diffuse abnormalities due to hypoperfusion complex. Recognition of these signs is important in order to prevent an unwanted outcome in hemorrhagic shock. We conclude that the halo sign is a useful one for hypoperfusion complex and that it is useful for assessing the degree of hemorrhagic shock.

• Journal of Trauma and Injury
• /
• v.30 no.4
• /
• pp.113-119
• /
• 2017

Purpose: Despite the numerous protocols and evidence-based guidelines that have been published, application of the therapeutics to eligible patients is limited in clinical settings. Therefore, a rounding checklist was developed to reduce errors of omission and the implementation results were evaluated. Methods: A checklist consisting of 12 components (feeding, analgesia, sedation, thromboembolic prophylaxis, head elevation, stress ulcer prevention, glucose control, pressure sore prevention, removal of catheter, endotracheal tube and respiration, delirium monitoring, and infection control) was recorded by assigned nurses and then scored by the staff for traumatized, critically ill patients who were admitted in the trauma intensive care unit (ICU) of Dankook University Hospital for more than 2 days. A total of 170 patients (950 sheets) between April and October 2016 were divided into 3 periods (period 1, April to June; period 2, July to August; and period 3, September to October) for the analysis. Questionnaires regarding the satisfaction of the nurses were conducted twice during this implementation period. Results: Record omission rates decreased across periods 1, 2, and 3 (19.9%, 12.7%, and 4.2%, respectively). The overall clinical application rate of the checklist increased from 90.1% in period 1 to 93.8% in period 3. Among 776 (81.7%) scored sheets, the rates of full compliance were 30.2%, 46.2%, and 45.1% for periods 1, 2, and 3, respectively. The overall mean score of the questionnaire regarding satisfaction also increased from 61.7 to 67.6 points out of 100 points from period 1 to 3. Conclusions: An ICU rounding checklist could be an effective tool for minimizing the omission of preventative measures and evidence-based therapy for traumatized, critically-ill patients without overburdening nurses. The clinical outcomes of the ICU checklist will be evaluated and reported at an early date.