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We developed a slim double-skin window (SDSW) with the aim of reducing building energy consumption for heating and cooling, thereby reducing the impact of buildings on climate change. The developed SDSW is a slim structure with an air cavity thickness of 20 mm, i.e., thinner than that of a traditional double-skin facade (DSF). We analyzed changes in the thermal properties and cooling and heating energy consumption of the SDSW as well as the effects of the thin air cavity on window performance. A testbed was constructed to analyze the seasonal temperature properties of the glass and the cooling and heating energy consumption. We also compared the long-term effects of the air cavity on the difference between outdoor and indoor glass surface temperatures under similar conditions for the SDSW and traditional DSF. The SDSW temperature was 3 °C lower than that of the traditional DSF, and the cooling and heating energy consumption dropped by 6.5%. Although the performance of the developed SDSW was comparable to that of traditional DSF, the life-cycle cost was reduced by 47%.

Introduction The purposes of this study were to compare the asymmetry index using panoramic radiography and cone-beam computed tomography for detecting mandibular posterior asymmetry and to evaluate the diagnostic value of the asymmetry index on panoramic radiography. Methods A total of 43 patients were included in this study. Ten mandibular posterior distances were measured using panoramic radiography and cone-beam computed tomography, and 10 asymmetry index values were calculated. The reliability of each asymmetry index was assessed. For evaluating validity of each asymmetry index using panoramic radiography, the paired t test and the Bland-Altman analysis were used. The accuracy of the asymmetry index and the area under the curve of receiver operator characteristic were calculated. Results The asymmetry index of total ramal height showed good reliability (ICC, >0.888). In condylar height 1, specificity and negative predictive value were low (0.08 and 0.17, respectively), 95% limits of agreement were ±17.9%, and area under the curve was 0.484. In total, ramal height accuracy was 0.86, and areas under the curve were 0.926 to 0.957. Conclusions For detecting asymmetry of the condyle region, the asymmetry index using panoramic radiography had little diagnostic value, and we recommend using cone-beam computed tomography images. However, the asymmetry index for total ramal height showed good reliability and relatively higher validity, and its diagnostic value was excellent.

The prostatic hyperplasia in benign prostatic hyperplasia (BPH) leads to obstructive micturition symptoms. Previous studies showed that pontine micturition center (PMC), ventrolateral periaqueductal gray (vlPAG), and medial preopticnucleus (MPA) regions in the brain have been known to regulate the urinary bladder function. The present study shows the influences of Panax ginseng on nerve growth factor (NGF) expressions in PMC, vlPAG, and MPA regions in the brain. Wistar rats were used for the present study. The rats split into four groups; 4 groups (n=6) in control group, BPH-induced group, BPH-induced and P. ginseng-treated group, and BPH-induced and finasteride-treated group. BPH in rats was induced by testosterone and the animals were evaluated for NGF expression in PMC, vlPAG, and MPA regions in the brain. The NGF expression was identified using immunohistochemistry (IHC). The NGF expression by IHC showed spots with dark brown color. In our results, NGF expressions in PMC, vlPAG, and MPA regions in the brainstem of the BPH-induced group showed increase than the control animal. These increased NGF expressions in three regions were decreased using treatment with P. ginseng (200mg/kg). These results suggest that P. ginseng has therapeutic effects on the symptoms of BPH and is associated with the regulation of NGF expression in the brain. In conclusion, the administration of P. ginseng helps nerve growth factor activation.

For integrated operation of the sulfur-iodine (SI) hydrogen production process, a HIx solution consisting of HI, I2 and H2O could be recycled as a reactant to the Bunsen reaction section from the HI decomposition section. In this study, characteristics of the Bunsen reaction using the HIx solution in a co-current flow mode were investigated experimentally. In particular, we studied the effects of the operating variables (feed rates of reactants, H2O and I2 feed concentrations, temperature and volume of reaction zone) on the characteristics of the Bunsen reaction under steady-state conditions. Increasing the H2O feed concentration and decreasing the I2 feed concentration improved the extent of the Bunsen reaction. When increasing the temperature, the purity of the Bunsen products improved, but the SO2 conversion decreased. Characteristics of the Bunsen reaction were not affected by the variation in the volume of reaction zone. We concluded that SO2/HI/I2/H2O feed molar ratio controlled in the ranges of 1/1.8–2.0/3.9–4.1/14.8–15.6 was advantageous to achieve high SO2 conversion and improve separation performance of the Bunsen products at 333 K.

Arteriovenous graft for hemodialysis vascular access is a widely used technique with many advantages. However, it has crucial complications with graft thrombosis and infection. We recently experienced an unusual case of arteriovenous graft complication involving graft thrombosis related to fistula formation between the graft and the natural vein with infection. We diagnosed this condition using Doppler ultrasound and computed tomography angiography. Successful surgical treatment including partial graft excision and creation of a secondary arteriovenous fistula using an inadvertently dilated cephalic vein was performed. The dialysis unit staff should keep this condition in mind and try to prevent this complication.

The stress corrosion cracking (SCC) behavior of Fe18Cr10Mn1Ni(0.3–0.8)N alloys was investigated in aqueous NaCl environment by using slow strain rate test method, and the results were compared to those of Ni-free counterparts. The addition of N tended to improve the SCC resistance of Fe18Cr10Mn- and Fe18Cr10Mn1Ni-based alloys. The alloying Ni magnified the beneficial effect of N on the SCC susceptibility and, eventually, the Fe18Cr10Mn0.8N alloy was immune to SCC in 2 M NaCl solution at 50 °C. The SCC behavior of the present alloys was found to be closely related to the repassivation tendency and the resistance to pitting corrosion.

The sensitization and intergranular corrosion associated with a phase transformation of tube-to-tubesheet welds of hyper duplex stainless steel were investigated using modified double loop electrochemical potentiokinetic reactivation. The susceptibility to sensitization of the hyper duplex stainless steel tube-to-tubesheet welded with an Ar shielding gas supplemented with nitrogen gas decreased owing to a decrease of the ferrite phase fraction and precipitation of chromium nitrides, thereby increasing the intergranular corrosion resistance. The intergranular corrosion in the hyper duplex stainless steel welds was selectively initiated at the Cr-depleted regions adjacent to the chromium nitride precipitates in the ferrite phases.

Stress corrosion cracking (SCC) susceptibility of austenitic Fe18Cr10Mn alloys with 0.3N, 0.6N and 0.3N0.3C was investigated in aqueous chloride environment using a slow strain rate test method. The SCC susceptibility of Fe18Cr10Mn alloys in 2 M NaCl solution at 50 °C under constant anodic potential condition decreased with increase in N content from 0.3 to 0.6 wt%, and with addition of 0.3 wt% C to the Fe18Cr10Mn0.3N alloys. The present study strongly suggested that the beneficial effects of N and C on the SCC behavior of Fe18Cr10Mn alloys would be associated with the resistance to pitting corrosion initiation and the repassivation kinetics.

In this study, a mock-up facility equipped with both BIPV windows and normal clear windows was installed to carry out the actual measurement of long-term surface temperature characteristics as the preliminary step for analyzing the impact of the surface temperature rise of thin film BIPV modules on the PV performance. The measurement was carried out for clear double windows and BIPV double windows simultaneously for each inclined angle (0°, 30°, and 90°) for one year, and various statistical analyses were carried out for the collected annual surface temperature data to investigate the surface temperature characteristics of BIPV windows. The analysis result shows that the temperature of windows applied on the vertical plane rises significantly during the winter season, and the temperature of windows applied on the horizontal plane and the inclined plane rises significantly during the summer season with high solar altitude. Regarding indoor surface temperature of windows which is closely related with the thermal comfort of indoor occupants, the surface temperature of BIPV windows with low solar heat gain coefficient was 1 °C lower than that of normal windows during the day time in summer season and was approximately 2 °C higher during the night time in winter season due to the thermal insulation effect.

The effects of shielding gas on the microstructure and localized corrosion of tube-to-tube sheet welds of SR-50A super austenitic stainless steel for seawater cooled condense were investigated in highly concentrated chloride environments. The localized corrosion resistance of the weld metal after welding with an Ar shielding gas supplemented with N 2 increased due to a decrease in the pitting resistance equivalent number (PREN) difference between the PREN IR of interdendritic region and the PREN DC of dendrite core. The localized corrosion was selectively initiated at the dendrite core because the PREN of the dendrite core was smaller than that of the interdendritic region.

Attrition of zinc-titanate sorbent particles were measured in a fluidized bed at a condition that attrition by gas jets of a distributor was dominant. Abrasion was found to govern the attrition of present sorbent particles. The top size of particles produced by attrition and the attrition rate increased with an increase of static bed height when the static bed height was less than jet penetration length of the distributor. However, the top size of produced particles and the attrition rate decreased with increasing static bed height when the static bed height was greater than jet penetration length of the distributor. Maximum values of the top size of produced particles and the attrition rate were found at a static bed height corresponding to a jet penetration length of the distributor. The top size of produced particles and the attrition rate increased with increasing relative humidity or gas velocity, whereas with decreasing temperature.

Background Double-tiered subchondral support (DSS) procedures with optimal distal dorsal cortical distance (DDD) have been reported to be effective in treating distal radius fractures, but there have been no studies of osteoporotic distal radius fractures in elderly patients. In this study, we demonstrated the efficacy of the DSS procedure with optimal DDD using a variable-angle volar locking plate system for the treatment of osteoporotic distal radius fractures in elderly patients. Methods A total of 122 patients (mean age, 73.3 years; age range, 65–88 years) with distal radius fracture were treated using a variable-angle volar locking plate system with DSS. Patients were divided into DSS and non-DSS groups based on postoperative and 12-month follow-up radiographs and radiological and clinical assessment was performed. Finally, we divided all 122 patients into two groups based on volar tilt of 6° on 12-month follow-up radiographs and postoperative DDD values were compared. Results Volar tilt decreased (p = 0.02), and ulnar variance increased (p = 0.01) more in the non-DSS group. The non-DSS group showed a significant correlation between postoperative DDD value and change in DDD value (p = 0.00). The mean postoperative DDDs in the group with final volar tilt Conclusion The use of the DSS procedure and reduction of DDD to 4.6 mm or less using a variable-angle volar locking plate system was effective in maintaining anatomical reduction for the treatment of osteoporotic distal radius fractures in elderly patients. Level of evidence III, therapeutic study.

The power output of PV module was characterized depending on incidence angle and the azimuth using a transparent thin-film solar cell in a mock-up model at various slopes to the south, as a building integrated photovoltaic system. Simulated data was also evaluated to determine the influence of the inclined angles and the azimuth on the power performance of the PV module. The experimental and computed data fitted comparatively well through the relative error estimation after calibration. It was found that the PV module with a slope of 30°, facing south, provided the best power performance according to an annual power output, producing about 2.5 times higher power output than that with the vertical module. Furthermore, the PV module facing south showed higher power output than that to the east. The varying power output of the PV module with inclined angles can be explained by the impact of the incidence angle modifier of the glass on the PV module. Specifically, the increased inclined slope of the PV module resulted in the reduced solar energy transmission, which producing a significant reduction of power output for the PV module with a slope over 70°.

This paper presents a simplified correlation method accounting for part-load performance of a chiller. First of all, parametric analysis was to present the influence of each input variable on partial loads at specific time and chiller capacity. Five variables, which were found to correlate well, were selected as inputs on the regression equations. A case study was carried out to test the applicability of this method with a 20 story office building in Seoul. The results of this method show good agreement with DOE-2 and measured data. When three alternatives were assumed for a cooling plant system, the differences of life cycle costs calculated for DOE-2 and this method were within 2%. Accordingly, it is believed that this simplified correlation method can be useful for determining the most economic alternative in the initial design stage.

In order to understand the effect of temperature on slug properties, the onset velocity of slugging, slug rising velocity and slug frequency have been measured by a differential pressure method in an electrically heated gas fluidized bed of 0.1 m i.d. and height of 1.97 m and, with respect to variations in gas velocity ( U mf ∼0.15 m/s) and temperature (25–400 °C). Air was used as fluidizing gas and fluid catalytic cracking (FCC) catalyst particle (Geldart's group-A particle, d p =0.071 mm, ρ p =1600 kg/m 3 ) as bed material. The minimum slugging velocity was found to increase a little with bed temperature. The qualitative change in minimum slugging velocity was found to agree with the inverse of minimum fluidizing velocity as temperature was varied. As the bed temperature increased, slug frequency was found to decrease a little, whereas slug rising velocity increased. A correlation between slug rising velocity and bed temperature was proposed.