• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.3
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• pp.661-667
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• 2016

This study evaluated the potential of methodology development of the helical type anchor for soft ground applications. The rotational penetration of the helix structure might make construction-steps easy without the soil spitting and reusable rods could reduce the material cost. Removal of the anchors would be simple as a construction, which can be named the removal anchor. The anchoring resistance after construction is strongly related to the number of helixes resulting in a concise design process. The investigation involved a chamber test with soft soils. In the test, a specially designed and fabricated helical anchor and torque-driver were used to obtain the maximum pull-out resistance of the anchor after rotational penetration. As a result of the tests, The rotational torque and pull-out resistance have a proportional relationship with the strength of the prepared soils. Within the range of the study, the torque of the anchor penetrating increased with increasing pull-out resistance.

• Clinical and Experimental Pediatrics
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• v.53 no.5
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• pp.648-652
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• 2010

Purpose: A brain abscess is a serious disease of the central nerve system. We conducted this study to summarize the clinical manifestations and outcomes of brain abscesses. Methods: A retrospective chart review of pediatric patients diagnosed with brain abscesses from November 1994 to June 2009 was performed at Samsung Medical Center, Seoul, Korea. Results: Twenty-five patients were included in this study. On average, 1.67 cases per year were identified and the median age was 4.3 years. The common presenting clinical manifestations were fever (18/25, 72%), seizure (12/25, 48%), altered mental status (11/25, 44%), and signs of increased intracranial pressure (9/25, 36%). A total of 14 (56%) patients had underlying illnesses, with congenital heart disease (8/25, 32%) as the most common cause. Predisposing factors were identified in 15 patients (60%). The common predisposing factors were otogenic infection (3/25, 12%) and penetrating head trauma (3/25, 12%). Causative organisms were identified in 64% of patients (16/25). The causative agents were $S$ $intermedius$ (n=3), $S$ $aureus$ (n=3), $S$ $pneumoniae$ (n=1), Group B streptococcus (n=2), $E.$ $coli$ (n=1), $P.$ $aeruginosa$ (n=1), and suspected fungal infection (n=5). Seven patients received medical treatment only while the other 18 patients also required surgical intervention. The overall fatality rate was 16% and 20% of patients had neurologic sequelae. There was no statistical association between outcomes and the factors studied. Conclusion: Although uncommon, a brain abscess is a serious disease. A high level of suspicion is very important for early diagnosis and to prevent serious consequences.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.19 no.2
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• pp.81-85
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• 2013

The stored-product insects have been a serious problem during the entire process of distribution on the food industry. Especially, the Indian meal moth (Plodia interpunctella) is one of stored-product insects which causes harm through penetrating into the food packaging. The objective of this study was to develop the anti-insect packaging material with fennel (Foeniculum vulgare) oil (FO). The FO has been selected for insecticidal substance against P. interpunctella, which was tested by fumigant toxicity assay. An anti-insect sachet was prepared by FO and filterpaper placed in a small paper bag. Repellent test was performed to evaluate the repellent activity of anti-insect sachet. In addition, the controlled release of FO from the anti-insect sachet was determined at $28^{\circ}C$ by gas chromatography (GC). It was demonstrated that FO was an effective substance against P. interpunctella. The mortality of FO was 56% at 800 mg/0.5 L in 120 h. In repellent test, the FO sachet showed effective repellency against P. interpunctella. The developed anti-insect sachet could be a promising source for insect repellent materials in food packaging.

• International Journal of Highway Engineering
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• v.18 no.5
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• pp.57-62
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• 2016

PURPOSES : The objective of this study is to evaluate the effect of size and depth of cavities on the pavement failure using the full-scale accelerated pavement testing. METHODS : A full-scale testbed was constructed by installing the artificial cavities at a depth of 0.3 m and 0.7 m from the pavement surface for accelerated pavement testing. The cavities were made of ice with a dimension of 0.5 m*0.5m*0.3m, and the thickness of asphalt and base layer were 0.2 m and 0.3 m, respectively. The ground penetrating radar and endoscope testing were conducted to determine the shape and location of cavities. The falling weight deflectometer testing was also performed on the cavity and intact sections to estimate the difference of structural capacity between the two sections. A wheel loading of 80 kN was applied on the pavement section with a speed of 10 km/h in accelerated pavement testing. The permanent deformation was measured periodically at a given number of repetitions. The correlation between the depth and size of cavities and pavement failure was investigated using the accelerated pavement testing results. RESULTS : It is found from FWD testing that the center deflection of cavity section is 10% greater than that of the intact section, indicating the 25% reduction of modulus in subbase layer due to the occurrence of the cavity. The measured permanent deformation of the intact section is approximately 10 mm at 90,000 load repetitions. However, for a cavity section of 0.7 m depth, a permanent deformation of 30 mm was measured at 90,000 load repetitions, which is three times greater than that of the intact section. At cavity section of 0.3 m, the permanent deformation reached up to approximately 90 mm and an elliptical hole occurred at pavement surface after testing. CONCLUSIONS : This study is aimed at determining the pavement failure mechanism due to the occurrence of cavities under the pavement using accelerated pavement testing. In the future, the accelerated pavement testing will be conducted at a pavement section with different depths and sizes of cavities. Test results will be utilized to establish the criteria of risk in road collapse based on the various conditions.

• Journal of Trauma and Injury
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• v.29 no.3
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• pp.93-97
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• 2016

Hepatic duct confluence injury, which is developed by blunt abdominal trauma, is rare. Conventionally, bile duct injury was treated by surgical intervention. In recent decades, however, there had been an increase in radiologic or endoscopic intervention to treat bile duct injury. In a hemodynamically stable patient, endoscopic intervention is considered as the first-line treatment for bile duct injury. A 40 year-old man was transferred to the emergency department of ${\bigcirc}{\bigcirc}$ trauma center after multiple blunt injuries. Contrast-enhanced abdominal computed tomography performed in another hospital showed a liver laceration with active arterial bleeding, fracture of the sacrum and left inferior pubic ramus, and intraperitoneal bladder rupture. The patient presented with hemorrhagic shock because of intra-peritoneal hemorrhage. After resuscitation, angiographic intervention was performed. After angiographic embolization of the liver laceration, emergency laparotomy was performed to repair the bladder injury. However, there was no evidence of bile duct injury on initial laparotomy. On post-trauma day (PTD) 4, the color of intra-abdominal drainage of the patient changed to a greenish hue; bile leakage was revealed on magnetic resonance cholangiopancreatography and endoscopic retrograde cholangiopancreatography (ERCP). Bile leakage was detected near the hepatic duct confluence; therefore, a biliary stent was placed into the left hepatic duct. On PTD 37, contrast leakage was still detected but both hepatic ducts were delineated on the second ERCP. Stents were placed into the right and left hepatic ducts. On PTD 71, a third ERCP revealed no contrast leakage; therefore, all stents were removed after 2 weeks (PTD 85). ERCP and biliary stenting could be effective treatment options for hemodynamically stable patients after blunt trauma.

• Journal of Chest Surgery
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• v.29 no.1
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• pp.79-85
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• 1996

A clinical evaluation was performed on 305 cases of chest trauma experienced at the department of the Thoracic and Cardiovascular Surgery, Dae Jeon Eul Ji Hospital, during the period from March 1991 to November 1994. Age distribution was from 4 to 85 years, the mosts common age groups were 4-th, 5th and 6th decades. The ratio of male to female was 229:76(3:1), the ratio showed male predominance, the most common cause of trauma was traffic accidents in nonpenetrating trauma and stab wounds in penetrating trauma. Hemothorax, pneumothorax, and hemopneumothorax were observed in 159 cases (52.1 %) of total cases, Rib fracture was observed in 236 cases (77.4%) of total cases, location distribution was right : left : Both (102 : 142 : 45), with left predominant, rib fracture commonly involved from the 3th to 8th rib. Lag period from accident to admission was 155 cases (50.8%) under 6hr The principles of therapy for early complications of chest trauma were rapid r expansion of the lungs by thoracentesis 5 cases(1.6%) and closed thoracostomy 1-42 cases(46.6%), but open thoracotomy had to be done on 17 cases (5.6%) because of massive bleeding 13 cases or ruptured diaphragm, foreign body. Conservative nonoperative treatment was 140 cases (45.9%). Overall mortality rate was Bcases (2.6%) and common causes of the death were respiratory insufficiency and shock.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.334-334
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• 2013

In the past decade, the infrared detectors based on intersubband transition in quantum dots (QDs) have attracted much attention due to lower dark currents and increased lifetimes, which are in turn due a three-dimensional confinement and a reduction of scattering, respectively. In parallel, focal plane array development for infrared imaging has proceeded from the first to third generations (linear arrays, 2D arrays for staring systems, and large format with enhanced capabilities, respectively). For a step further towards the next generation of FPAs, it is envisioned that a two-dimensional metal hole array (2D-MHA) structures will improve the FPA structure by enhancing the coupling to photodetectors via local field engineering, and will enable wavelength filtering. In regard to the improved performance at certain wavelengths, it is worth pointing out the structural difference between previous 2D-MHA integrated front-illuminated single pixel devices and back-illuminated devices. Apart from the pixel linear dimension, it is a distinct difference that there is a metal cladding (composed of a number of metals for ohmic contact and the read-out integrated circuit hybridization) in the FPA between the heavily doped gallium arsenide used as the contact layer and the ROIC; on the contrary, the front-illuminated single pixel device consists of two heavily doped contact layers separated by the QD-absorber on a semi-infinite GaAs substrate. This paper is focused on analyzing the impact of a two dimensional metal hole array structure integrated to the back-illuminated quantum dots-in-a-well (DWELL) infrared photodetectors. The metal hole array consisting of subwavelength-circular holes penetrating gold layer (2DAu-CHA) provides the enhanced responsivity of DWELL infrared photodetector at certain wavelengths. The performance of 2D-Au-CHA is investigated by calculating the absorption of active layer in the DWELL structure using a finite integration technique. Simulation results show the enhanced electric fields (thereby increasing the absorption in the active layer) resulting from a surface plasmon, a guided mode, and Fabry-Perot resonances. Simulation method accomplished in this paper provides a generalized approach to optimize the design of any type of couplers integrated to infrared photodetectors.

• Economic and Environmental Geology
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• v.36 no.2
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• pp.123-131
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• 2003

Geophysical surveys(electrical resistivity, self-potential, seismic refraction, GPR) were conducted to investigate the physical properties of the subsurface, and to delineate the flow channel of leachate from a AMD(acid mine drainage), buried rock wastes and tailings, and drainage pipes at an abandoned mine(Kwangyang mine). Especially in rainy season the sites appear to be abundant in AMD leachate, characterized by electrical conductivities of 0.98-1.10 ms/S. Electrical resistivity sections indicate that the leachate flows running in two directions at southern part rise up through the narrow fracture zones at the central part and contaminates the surrounding soil and stream. Such schematic features at the anomalous zone are well correlated with negative peaks in self-potential data, the limited penetration depth in GPR data and low velocity zone in seismic refraction data. Shallow high-resistivity zone is associated with the buried rock wastes which cause the diffractions in GPR image. In addition, the events at depth of approximately 1-1.25 m in GPR sections must be the metal pipes through which AMD is drained off to the inner bay.

• Archives of design research
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• v.18 no.1 s.59
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• pp.135-144
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• 2005

Consumers' awareness of product value, and their product preferences, are becoming increasingly influential in product development, particularly in corporations' efforts in manufacturing products with a competitive edge. Corporations conduct surveys on consumers' product satisfaction and preferences and conduct in-depth studies on consumer needs. They then manufacture products in accordance with the results of these surveys and studies. With the necessity and demand for digital door lock products recently growing, this research sought to explore product competitiveness reinforcement factors that could facilitate market penetration, and to formulate corresponding design strategies. In-depth consumer interviews were also conducted to identify consumer lifestyles and needs. Furthermore, consumer preference images, purchase and use-related patterns, and the status of door lock markets were studied. In the past, to design and manufacture consumer-oriented products, corporations primarily resorted to the improvement of the products' technological features. At present, the users' product preferences and the ways that they use these products are the factors that determine product design. Consumers today tend to adjust their lifestyles according to available products, and prefer products that have greater value in terms of lifestyle and culture. Strategic points for reinforcing competitiveness were presented in this study: first, offering different values that will enhance consumer satisfaction, second, positively developing bio-recognizable methods that will boost consumer preference, third, meeting the consumers' expectations that door lock products should not be mere 'entrance and exit control' systems, but network security systems and fourth, adopting convenient authentication methods backed by advanced technologies.

• Journal of Korean Tunnelling and Underground Space Association
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• v.17 no.3
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• pp.319-332
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• 2015

The pressure wave formed by the piston effects of the train proceeds within the tunnel when a train enters the tunnel with a high speed. Depending on the condition of tunnel exit, the compression waves reflect at a open end, change to the expansion waves, transfer to tunnel entrance back. Due to interference in the pressure waves and running train, passengers experience severe pressure fluctuations. And these pressure waves result in energy loss, noise, vibration, as well as in the passengers' ears. In this study, we performed comparison between numerical analysis and field experiments about the characteristics of the pressure waves transport in tunnel that appears when the train enter a tunnel and the variation of pressure penetrating into the train staterooms according to blockage ratio of train. In addition, a comparative study was carried out with the ThermoTun program to examine the applicability of the compressible 1-D model(based on the Method of Characteristics). Furthermore examination for the adequacy of the governing equations analysis based on compressible 1-D numerical model by Baron was examined.