• Solar Energy
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• v.20 no.4
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• pp.31-43
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• 2000

A model house with a "Ondol" heating working with solar energy and supplied by circulation air was investigated both experimentally and theoretically, A calculation method was developed for interpreting the measured values and for comparing several variants, This calculation method together with the measurement result is presented in the following. The gain in energy of the collector(Trombe wall type with TWD) measured on a particularly selected winter day with plenty of radiation amounted to approximately 31 % of the total solar radiation.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2402-2407
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• 2007

Heat transfer distributions and friction factors in square channels (3.5 ${\times}$ 3.5 cm) with twisted tape inserts and with twisted tape inserts plus interrupted ribs are respectively investigated. Tests are performed for Reynolds numbers ranging from 8,900 to 29,000. The rib height-to-channel hydraulic diameter, e/Dh, is kept at 0.057 and test section length-to-hydraulic diameter, L/Dh is 30. The twisted tape is 0.1 mm thick carbon steel sheet with diameter of 3.3cm, length of 90cm, and 2.5 turns. The square ribs are arranged to follow the trace of the twisted tape and along the flow direction defined as axial interrupted ribs. Each wall of the square channel is composed of isolated aluminum sections. The following conclusions from the experimental study were drawn as: 1) In the 4 heating wall channel with twisted tape inserts, Nusselt number based on bottom wall temperature is enhanced by 1.2 - 1.6 times if adding the axial interrupted ribs on the bottom wall only. 2) The twisted tape with interrupted ribs under the two-sided heating condition produces the highest heat transfer performance. 3) Friction factor data obtained for the square channel with twisted tape inserts plus axial interrupted ribs are less than those in the past publications for circular tubes with axial interrupted ribs and twisted tape inserts.

• Journal of the Korea Institute of Building Construction
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• v.20 no.3
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• pp.261-267
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• 2020

This study used a real-scale model experiment to reproduce internal fires in residential buildings such as a multi-dwelling unit, in order to prevent damage caused by tens of thousands of fires witnessed each year and to take measures to cope with them. For experimental conditions, different opening sizes were applied to measure and analyze the heating temperature of the exterior wall. Results drawn are as following: when the experiment was conducted with opening sizes(horizontal length) each at 2,000mm, 1,600mm, and 1,400mm, the flashover occurred at 630 seconds, 505 seconds and 510 seconds, respectively. Also, the total heating time, in proportion to this, came to 815 seconds, 713 seconds and 721 seconds. The maximum heating temperature of the exterior wall by the opening size reached 282.4℃ at 2,000mm, 382.9℃ at 1,600mm, and 423.8℃ at 1,400mm. This represented that as the opening size gets smaller, the heating temperature of the exterior wall by fire spread becomes higher.

• Microbiology and Biotechnology Letters
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• v.17 no.4
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• pp.313-320
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• 1989

Rhodotorula glutinis K-24 was found to produce internal, cell wall bound, and external invertase. Internal invertase was purified by column chromatographies on DEAE-Sephadex A-50, Sp-sephadex C-50, gel filtration on Sephadex G-200 and isoelectric focusing. Cell wall bound invertase was partially purified by the following procedures; column chromatography on DEAE-Sephadex A-50 and gel filtration on Sephadex G-100. Optimum pH and temperature for enzymatic activities of internal and cell wall bound invertase were pH 3.0 and 6$0^{\circ}C$, respectively. Both enzymes were inhibited by HgC1$_2$, AgNO$_3$, MnSO$_4$, and sodium dodecylsulfate. The molecular weights of internal and cell wall bound invertases were estimated to be 310,000 and 61,000, respectively. Other physicochemical properties of the both enzymes were similar.

• The KIPS Transactions:PartB
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• v.10B no.7
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• pp.837-846
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• 2003

This paper deals with plain figures on the architectural drawings of apartment. This kind of architectural drawings consist of main walls represented by two parallel bold lines, symbols (door, window, $\cdots$), dimension line, extension line, and dimensions represent various numerical values and characters. This paper suggests a method for recognizing main wall which is a backbone of apartment in an architectural drawing. In this thesis, the following modules are realized : an efficient image barbarization, a removal of thin lines, a vectorization of detected lines, a region bounding for main walls, a calculation of extension lines, a finding main walls based on extension line, and a field expansion by searching other main walls which are linked with the detected main walls. Although the windows between main walls are not represented as main walls, a detection module for the windows is considered during the recognition period. So the windows are found as a part of main wall. An experimental result on 9 different architectural drawings shows 96.5% recognition of main walls and windows, which is about 5.8% higher than that of Karl Tombre.

• Archives of Reconstructive Microsurgery
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• v.7 no.2
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• pp.114-121
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• 1998

The purpose of this study is to investigate the appropriate management of severe radionecrotic wounds of the anterior chest wall associated with infection of the soft tissues and ribs and exposure of vital structures(heart and lung), and present our strategies for reconstruction of these complicated patients. 9 patients have undergone radical debridement and immediate microsurgical reconstruction for severe radionecrotic wounds of the anterior chest wall over last 7 years. All patients had extensive osteomyelitis of the ribs or sternum, and chronic infection or cutaneous fistulae. 2 patients had pericardial effusions due to longstanding inflammation, and 6 patients had pleural effusions. 2 patients had ipsilateral lung collapse. 10 free flaps were performed for coverage of the huge defects. One patient required 2 free flaps to control the inflammation. 8 free TRAM flaps were used for coverage of the defects and in addition, the rectus abdominis muscle was packed into any deep cavity. 1 patients underwent latissimus dorsi muscle free flap because of previous abdominal surgery. After extensive debridement of the infected, radionecrotic wounds, all 10 free flaps were successful. All the extensive radionecrotic defects of the anterior chest wall were completely healed. Free flaps successfully covered the exposed vital structures of the heart and lungs. Patients with severe radionecrotic defects of the anterior chest wall after ablative breast cancer surgery and radiotherapy were successfully treated by radical debridement and immediate free flap surgery. The TRAM flap together with the rectus muscle is the treatment of choice for these huge defects. The latissimus dorsi muscle flap was the second choice in patients with previous abdominal surgery. The recipient vessel should be carefully selected because of possible radiation damage and inflammation.

• KIEAE Journal
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• v.7 no.1
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• pp.33-40
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• 2007

0.4 Million tons of shell powder have been disused as waste in KOREA and caused severe environmental pollution though shell powder can be utilized in real life for many ways. It is impending problem to recycle shell powder as it requires high expense for burying and temporary outside heap and causes severe environmental pollution being a main factor of ocean waste. To suggest the basic data for development of eco-friendly and high-function Wall Coatings Thin Textured Finishes, a wall coating sample was applied to indoor walls of a mock-up and temperature and humidity were measured to assess the thermal performance of it, and a survey of preference for the color sense and feel of the materials with a movie of specimens. The results of the study are following; 1) High insulation performance is shown from the assessment result of the room polystyrene board adhered on the walls then high humidity controlling performance is shown from that of the room polystyrene board coated by shell powder. This point out that shell powder has superiority for humidity controlling. 2) The result of thermal and humidity assessment shows that shell powder makes up for thermal conduction of the polystyrene board and same result can be expected from the assessment with materials which has similar thermal characteristics with polystyrene.3) Ranking of preferred specimens is; 1st Case 13, 2nd Case 17, 3rd Case 16, and 4th Case 12. Preferred shell powder was the ark shell. Preferred powder for plaster was the powder mixed with that sifted by 0.8mm, 100mesh and 40mesh, and for spray was the fine powder mixed with that sifted by 100mesh and 40mesh.

• Archives of Plastic Surgery
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• v.39 no.3
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• pp.204-208
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• 2012

Background : Isolated pure blowout fractures are clinically important because they are the main cause of serious complications such as diplopia and limitation of extraocular movement. Many reports have described the incidence of blowout fractures associated with diplopia and limitation of extraocular movement; however, no studies have statistically analyzed this relationship. The purpose of this study was to demonstrate the correlation between the location of isolated pure blowout fractures and orbital symptoms such as diplopia and limitation of extraocular movement. Methods : We enrolled a total of 354 patients who had been diagnosed with isolated pure blowout fractures, based on computed tomography, from June 2008 to November 2011. Medical records were reviewed, and the prevalence of extraocular movement limitations and diplopia were determined. Results : There were 14 patients with extraocular movement limitation and 58 patients complained of diplopia. Extraocular movement limitation was associated with the following findings, in decreasing order of frequency: floor fracture (7.1%), extended fracture (3.6%), and medial wall (1.7%). However, there was no significant difference among the types of fractures (P=0.60). Diplopia was more commonly associated with floor fractures (21.4%) and extended type fractures (23.6%) than medial wall fractures (10.4%). The difference was statistically significant (Bonferroni-corrected chi-squared test P<0.016). Conclusions : Data indicate that extended type fractures and orbital floor fractures tend to cause diplopia more commonly than medial wall fractures. However, extraocular movement limitation was not found to be dependent on the location of the orbital wall fracture.

• Restorative Dentistry and Endodontics
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• v.12 no.1
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• pp.51-64
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• 1986

The purpose of this study is to obtain the data of prestep in cavity preparation by observing changed conditions of laser irradiated dental hard tissues. The forty five extracted caries free human molars were divided into three groups and each group into five subgroups. A $CO_2$ laser irradiation was performed each subgroup of group I for one second with output power of 5 W, 10 Wand 20 W. On group II, laser irradiation was done ten times for 0.1 second duration using same power ratings as group I. On group III, laser irradiation was done 0.1 second, 0.2 second and 0.4 second with output power of 50 W. We investigated mineral contents and crater wall of obtained specimens, i.e., laser irradiated teeth, using computer controlled electron probe microanalyzer and scanning electron microscope. The following results were obtained: 1. Both calcium and phosphorus contents in laser irradiated enamel crater wall were increased, and magnesium content was decreased, but these trends were not statistically significant. 2. In laser irradiated dentin, change of mineral content was more significant. 3. In laser irradiated enamel and dentin, there were no significant differences on mineral content change due to irradiation condition and energy density. 4. In scanning electron microscopic study, enamel rods of the crater wall were fused and clefts were observed in parallel with the direction of enamel rod for all groups. 5. In laser irradiated dentin, irregular fusion and clefts were observed. In irradiated teeth with high power and short duration, the locally formed narrow crater wall was observed.

• Steel and Composite Structures
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• v.33 no.4
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• pp.569-581
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• 2019

Corrugated steel plate shear wall (CSPSW) as an innovative lateral load resisting system provides various advantages in comparison with the flat steel plate shear wall, including remarkable in-plane and out-of-plane stiffnesses and stability, greater elastic shear buckling stress, increasing the amount of cumulative dissipated energy and maintaining efficiency even in large story drifts. Employment of low yield point (LYP) steel web plate in steel shear walls can dramatically improve their structural performance and prevent early stage instability of the panels. This paper presents a comprehensive structural performance assessment of corrugated low yield point steel plate shear walls having circular openings located in different positions. Accordingly, following experimental verification of CSPSW finite element models, several trapezoidally horizontal CSPSW (H-CSPSW) models having LYP steel web plates as well as circular openings (for ducts) perforated in various locations have been developed to explore their hysteresis behavior, cumulative dissipated energy, lateral stiffness, and ultimate strength under cyclic loading. Obtained results reveal that the rehabilitation of damaged steel shear walls using corrugated LYP steel web plate can enhance their structural performance. Furthermore, choosing a suitable location for the circular opening regarding the design purpose paves the way for the achievement of the shear wall's optimal performance.