• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.35 no.6
• /
• pp.1259-1267
• /
• 2015

In Korea, rural groundwater development faces new challenge, which have not been experienced so far. The problem is a groundwater depletion by the water curtain cultivation (WCC) during winter season. This study investigates the groundwater depletion using three-dimensional finite difference groundwater flow program, MODFLOW to verify the water budget of the shallow aquifer of Cheongweon area. Interdisciplinary research, which has become a worldwide trend, has been adopted in studying groundwater modeling in field scale. In particular, the method of groundwater recharge estimation adopted precise modeling techniques, SWAT to groundwater flow modeling. Based on qualified field data, the model calibrated and validated its reliability. The objective of this study is to simulate various stream-aquifer interactions according to groundwater pumping with artificial boundaries, such as weirs and drainage system. We also analyzed a seasonal variation of cumulative water budget of the site to quantify the groundwater depletion and recovery in the pumping field.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.18 no.2
• /
• pp.323-336
• /
• 1996

This is a retrospective study on the patients with infection of the oral and maxillofacial region with the purpose of obtaining some useful data for diagnosis and treatment plan of that relatively common disease in dentistry. The used materials of study were 87 in total, including 52 male patients, 35 female patients who diagnosed and treated at the Department of the Dentistry in Hanyang Medical College Hospital for the period of Jan. 1990 to Dec. 1994. The author analyzed the distribution and incidence of sex, age, admission period, etiologic factors, etiologic teeth, treatment method of infections, pus culture, antibiotics sensibilities and medication. The result obtained as follows : 1. The developmental incidences by sex was superior in male by the ratio of 1.5 : 1 and the infection was most frequently occurred during the third decades(35.6%). 2. The number of admitted patients elevated in February, March, and April, and average of admission period was 9.8 days. 3. Main etiologic teeth showed on lower molar region in adult(63%) and upper molar region in primary dentition(46.1%). 4. Medications were administrated in all of the cases, and surgical incision and drainage were performed in 53% and extraction of the causative teeth were performed in 63.6% of all cases. 5. The most common involved fascial spaces were Buccal space(41.4%), Infraorbital space(27.6%), Submandibular space(16.1%),in order, and 9 cases(10.3%) were Ludwig's Angina. In 68.2% of the patients, and infection involved only one fascial space and in 21.8% of the patients, it involved to more fascial spaces. 6. The most causative organisms isolated from pus culture were Gram-positive facultative cocci(55.5%), and antibiotics sensitivities on the total isolated bacterial strains were exposed chloramphenicol(88.6%), Cephalothin(88.6%), Erythromycin(81.5%), Lincomycin(77.8%) in order, but it showed resistant on Gentamycin(58.3%), Tetracycline(56.5%), Methicillin(38.5%).

• Journal of the Korean GEO-environmental Society
• /
• v.2 no.3
• /
• pp.57-69
• /
• 2001

Sand pile is widely used as a ground improvement method. Although the primary purpose of constructing sand pile is accelerating consolidation, composite ground effect also can be gained by constructing sand pile. This study was accomplished to understand composite ground effect on the ground improved by sand piles which were applied as vertical drainage material when area replacement ratio was small relatively. For determining bearing capacities of origin ground and sand piles and analysing interaction between embankment and origin ground, bearing tests and earth pressure monitoring are performed. From the results, it turned out that the contribution of sand pile as a load bearing mechanism is not substantial. However, the bearing capacity of sand pile was increased to sixty percentages when compared with origin ground. The increasement of bearing capacity could be caused the change of consolidation characteristics during the process of consolidation by overburden load. Therefore, the composite ground effects depending on stiffness increasement of sand pile would be estimated as a factor decreasing consolidation settlement.

• Journal of the Korean GEO-environmental Society
• /
• v.2 no.4
• /
• pp.63-72
• /
• 2001

As construction cases on soft ground are increasing, the necessity of ground improvement is also increasing. Granular pile is one of the methods for soft clay and for loose sandy soil. In our country, SCP(Sand Compaction Pile) method using sand material has been mainly used to improve soft ground, but Granular pile with crushed-stone was not used much. However, alternative material such that crushed-stone is needed to substitute for sand due to the environmental and economical problems. In this study, staged load test and consolidation test were performed in the laboratory to observe the behavior of soft ground improved by Granular pile. In order to evaluate the characteristics such as bearing capacity, drainage, and settlement, sand and crushed-stone were applied as each pile material. The test results show that crushed-stone has higher bearing capacity and less settlement than those of sand under similar pore water pressure condition. Therefore, crushed-stone is determined to be appropriate as substitute for sand.

• Archives of Reconstructive Microsurgery
• /
• v.8 no.1
• /
• pp.44-49
• /
• 1999

From January 1990 to December 1998, 449 consecutive single-digital replantations were reviewed retrospectively in order to determine the essential number of vascular anastomoses for successful finger replantation. The correlations between the number of anastomosed vessels and survival rate were examined according to the amputated digital levels and all of the correlated results were compared with each other statistically. In zone I, The survival rate of the digits with a repaired vein was higher than that of digits treated with external bleeding method. In zone II, the equal number(s) between the arterial and venous repair was an important factor in successful replantation. And the repaired arteries more than repaired veins in number led to venous congestion and resulted in a failure of replantation, which was maybe due to the large amount of arterial input relative to small volume of amputated stump with small sized vein. In zone III, the equal number(s) between the arterial and venous repair was also an important factor in successful replantation. But unlike in zone II, venous congestion was scarcely happened if the venous drainage was sufficient with a repaired large vein alone. In zone IV, two or more arteries and veins were required for successful replantation. In conclusion, it is desirable that the repair of vessels as many as possible to increase the possibility of a good result. But digital amputations and their condition for replantation were variable, therefore, the numbers in vascular repair should to be modified and straightforward as the case may be.

• Journal of Korea Water Resources Association
• /
• v.44 no.4
• /
• pp.263-273
• /
• 2011

Recently increased rainfall by abnormal climate, risen peak runoff by urbanization, and shorten time of concentration are causing frequent overflow at downstream basin. This problem will be solved through the runoff reduction facilities like detention pond. However so far, most studies about detention pond in Korea are focused on its capacity. A study with respect to outlet facilities of detention pond was insignificant. Design of culvert usually used for outlet facilities of detention pond is generally carried out by using "Road Drainage Design" of Korea Expressway Corporation (1991). So detention pond is unreasonable to apply it. In this study, the culvert flow in submerged condition of upstream at culvert was analyzed., and simplified design procedure for culvert outlet facilities were presented for detention pond.

• Journal of Korea Technical Association of The Pulp and Paper Industry
• /
• v.30 no.2
• /
• pp.47-54
• /
• 1998

Refining is one of the most important processes of fiber treatment that provides optical and physical properties of final paper products. The evaluation method of refining progress is usually freeness (CSF) or wetness (SR) test because of its rapidity and convenience. However, there are some deficiencies in using freeness or wetness test to evaluate pulp fibers accurately because its results are more influenced by fines contents than extent of fibers treatment. The objective of this study is to show the deficiency of wetness in evaluating the refining process. For this, beating is done by varying the beating load. Handsheets are made after beating until 25 and $32^{\circ}C$ SR, and then paper properties are measured. Refined fibers are analyzed by fiber length, fines contents, curl, kink, WRV, and zero-span tensile strength. The results show that longer beating time is required to reach the same wetness at lower beating load. There are differences in the average fiber length, distribution curve of fiber length, fines contents, curl, kink, WRV of long fiber fraction, drainage time, and zero-span tensile strength of rewetted sample at different beating load. At the low beating load in the same wetness, apparent density, breaking length, burst strength, and tear strength are higher, while opacity and air permeability are lower than those of the high beating load. Using Page s equation, which shows the relationship among tensile strength, intrinsic fiber strength, and interfiber bonding strength, interfiber bonding strength is calculated and analyzed to explain final paper properties. At $25^{\circ}C$ SR, interfiber bonding strength is only slightly higher at 2.5kgf beating load, while the intrinsic fiber strength is substantially higher. At $32^{\circ}C$ SR, intrinsic fiber strength is a little bit higher at 2.5kgf beating load, and interfiber bonding strength is remarkably higher than those of 5.6kgf beating load. These results can be used to explain the different properties of the final paper at selected beating loads.

• Journal of Chest Surgery
• /
• v.29 no.8
• /
• pp.905-909
• /
• 1996

From 1991 to 1994, We performed 75 cases of pulmonary resection. These were divided into two groups according to the method of bronchial stump closure : 51 cases automatic staplers were a plied in 49 patients (Group 1), 24 patients were closed with manual interrupted suture (Group II). Disease entities of the patients were malignant tumor in 33 patients(Group I: Group II, 22· II, bronchiectasis in 23(18:5), benign tumor in 5(3:2), aspergilloma in 5(2:3), tuberculosis(2:1) in 3, bronchogenic cyst in 2 (0 : 2) and so on. Surgical Procedure% for these Patients were 21 Pneumonectomies(18:3), 13 bilobectomies(11:2), 26 lobectomles (14:12), 11 segmentectomies (6:5) and 4 lobectomy with segmentectomies (4:0). In conclusion, the Amount of tube drainage was smaller and the removal of chest tube after surgery was shorter than manual bronchial closure group by means of statistical significance (p=0.047, p=0.005). Although there were no statistical significance, the duration of air leakage was reduced and incidence of bronchopleural rstula was reduced in the stapler used group compared with manual bronchial closure.

• Journal of Korean Neurosurgical Society
• /
• v.29 no.2
• /
• pp.249-254
• /
• 2000

Objective : As a minimally invasive strategy, endoscopic technique was introduced for removal of the traumatic intracerebral hematoma. Material and Method : A 54-year-old man with three-day history of seizure and progressive mental deterioration after traffic accident was presented. Computerized Tomography(CT) of the brain showed a huge intracerebral hematoma on the right frontal lobe and ventricle. The operation was performed via right frontal superolateral keyhole with 2cm eyebrow skin incision. Using 0-degree and 30-degree angled lens 4mm rigid endoscopes, nearly all of the hematoma was evacuated under the direct endoscopic visualization and a ventricular catheter was exactly placed into the frontal horn of the right lateral ventricle at the end of procedure. Results : The seizure was discontinued and neurological status had been improved during postoperative periods. Postoperative CT demonstrated that most of the hematoma was removed and the ventricular drainge tube was exactly placed in the right foramen of Monro. Conclusion : With endoscopic technique, the authors successfully evacuated traumatic intracerebral hematoma and exactly placed the ventricular drainage catheter under direct visualization. This technique may be considered as an another option for removal of traumatic intracerebral hematoma.

• Journal of Korean Neurosurgical Society
• /
• v.58 no.1
• /
• pp.36-42
• /
• 2015

Objective : Complete sellar floor reconstruction is critical to avoid postoperative cerebrospinal fluid (CSF) leakage during transsphenoidal surgery. Recently, the pedicled nasoseptal flap has undergone many modifications and eventually proved to be valuable and efficient. However, using these nasoseptal flaps in all patients who undergo transsphenoidal surgery, including those who had none or only minor CSF leakage, appears to be overly invasive and time-consuming. Methods : Patients undergoing endoscopic endonasal transsphenoidal tumor surgery within a 5 year-period were reviewed. Since 2009, we classified the intraoperative CSF leakage into grades from 0 to 3. Sellar floor reconstruction was tailored to each leak grade. We did not use any tissue grafts such as abdominal fat and did not include any procedures of CSF diversions such as lumbar drainage. Results : Among 200 cases in 188 patients (147 pituitary adenoma and 41 other pathologies), intraoperative CSF leakage was observed in 27.4% of 197 cases : 14.7% Grade 1, 4.6% Grade 2a, 3.0% Grade 2b, and 5.1% Grade 3. Postoperative CSF leakage was observed in none of the cases. Septal bone buttress was used for Grade 1 to 3 leakages instead of any other foreign materials. Pedicled nasoseptal flap was used for Grades 2b and 3 leakages. Unused septal bones and nasoseptal flaps were repositioned. Conclusion : Modified classification of intraoperative CSF leaks and tailored repair technique in a multilayered fashion using an en-bloc harvested septal bone and vascularized nasoseptal flaps is an effective and reliable method for the prevention of postoperative CSF leaks.