• Structural Engineering and Mechanics
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• v.75 no.5
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• pp.529-540
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• 2020

The mechanical properties of timber construction have drawn more attention after the 2013 Lushan earthquake. A strong desire to preserve this ancient architectural styles has sprung up in recent years, especially for residential buildings of the mountainous areas. In the column-and-tie timber construction, continuous-tenon joints are the most common structural form to connect the chuanfang (similar to the beam in conventional structures) and the column. To study the cyclic performance of the continuous-tenon joints in column-and-tie timber construction, the reversed lateral cyclic loading tests were carried out on three 3/4 scale specimens with different section heights of the chuanfang. The mechanical behavior was assessed by studying the ultimate bending capacity, deformation ductility and energy dissipation capacity. Test results showed that the slippage of chuanfang occurred when the specimens entered the plastic stage, and the slippage degree increased with the increase of the section height of chuanfang. An obvious plastic deformation of the chuanfang occurred due to the mutual squeezing between the column and chuanfang. A significant pinching was observed on the bending moment-rotation curves, and it was more pronounced as the section height of chuanfang increased. The further numerical investigations showed that the flexural capacity and initial stiffness of the continuous-tenon joints increased with the increase of friction coefficient between the chuanfang and the column, and a more obvious increasing of bending moment occurred after the material yielding. The compressive strength perpendicular to grain of the material played a more significant role in the ultimate bending capacity of continuous-tenon joints than the compressive strength parallel to grain.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.485-489
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• 2003

Enzymatic hydrolysis of egg yolk Protein was carried out in continuous packed column reactor Five supports for enzyme immobilization were evaluated in this study. We investigated the optimum operation variables - pH, temperature, and flow rate in continuous reactor operation.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.11a
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• pp.171-172
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• 2012

In this study the continuous rectangular spiral hoop is used for saving cost and time, solving manpower shortage, and the quality of structures. Generally the use of continuous spiral reinforcement in reinforced concrete elements improve the strength and the ductility of the concrete. Savings in cost and time is demonstrated with the continuous rectangular spiral hoop through the mock up test of beam and column elements. In case of a 4m column element the time of rebar work decreases up to 40% compared with traditional hoop, and in case of a 8m beam the time also decreases 40%. This study present the construction method and details.

• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.497-503
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• 1991

The catalytic activities of immobilized gIucoamylase in a packed bed column and a continuous stirred tank reactor have been compared. Rapid production of glucose from liquefied starch have been studied through, the continuous liquefaction and saccharification using settling chamber. The immobilized glucoamylase with chitin gave the saccharification yield of 20% with the dextrin concentration of 100 g/l in a residence of 20 min. in a packed bed column. The half-life of immobilized glucoamylase with chitin was 19 days. The glucoamyalse immobilized in chitin and encapsulated with Ca-alginate gave the saccharification yield of 6% with the dextrin concentration of 50 g/l in a residence of 20 min. in a packed bed column. The Ca-alginate encapsulated and chitin immobilized glucomylase had a half-life of 25 days, which is 6 day larger than that of the immobilized glucoamylase with chitin only. In continuous liquefaction and saccharification, the glucose yield was 17% for the liquefied starch with naked barley concentration of 50gA in a residence of 20 min.

• KSBB Journal
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• v.5 no.4
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• pp.329-334
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• 1990

In an attempt to develop a novel process for ethanol production from starch, a simultaneous saccharification and fermentation (SSF) process using Zymomonas mobilis and amyloglucosidase (AMG) was studied in continuous modes. Compared with a conventional cylindrical column type of fermentor, the tapered column type of fermentor was found to be superior in terms of reactor performance for ethanol fermentation. The tapered columm fermentor packed with coimmobilized Z. mobilis and AMG alleviated the problems which were associated with CO2 evolution and provided a significantly better flow pattern for both liquid and gas phases in the fermentor without channelling. However, the fluidized bed type of tapered column fermentor using flocculent strain of Z. mobiles and immobilized AMG showed lower productivity (5.2g/1/h) than that of packed bed type of tapered column fermentor(9.2g/l/h).

• Journal of the Korea Institute of Building Construction
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• v.13 no.3
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• pp.291-305
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• 2013

This paper presents the continuous hoop reinforcement method as a means to overcome the difficulty of rebar construction due to the seismic detail of lateral reinforcement. Because the continuous hoop has no seismic hook, and there is less interference during the rebar work, rebar quantities and construction time can be reduced. Since the details of column and beam continuous hoops are different from those of conventional lateral reinforcements, the construction method should be developed through mock-up tests. The length of the beam mock-up is 8m and the section size is $500mm{\times}700mm$, the height of the column mock-up is 2.8m and 4m, and the section size is $800{\times}800mm$. The length and the size are determined based on the elements that are generally used in reinforced concrete basement parking lots and office buildings. The results of the mock-up test showed that the quantities of rebar could be reduced by 20% and the time could be reduced by up to 40% compared with conventional lateral reinforcements.

• Journal of the Korea institute for structural maintenance and inspection
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• v.11 no.6
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• pp.159-168
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• 2007

The problem of determination of axial force in continuous welded rail(CWR) has attracted a number of railroad engineers due to its practical importance in prevention of accidents related to buckling and pull apart. In this paper, we investigated the application of the beam-column theory to presume the axial force in CWR and proposed the development process of the prediction equation and model to presume the axial force in CWR.

• Journal of the Korean Society of Safety
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• v.8 no.2
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• pp.44-50
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• 1993

The objective of this study was to investigate the extraction of chromium(Vl) ion in waste water through the liquid surfactant membrane with open-type Perforated Reciprocating-Plate Column. Extraction experiments were conducted to measure the effect of flow characteristics of continuous and dispersed phase and stroke velocity, sodium hydroxide concentraction in internal aqueous phase, sulfuric acid concentraction in outer phase, and residence time distribution and measured extraction velocity. The result of experiments showed that extraction velocity of chromium ion was maximum when stroke velocity was 180 1/min and dispersion phase velocity was 30m11min, continuous phase velocity was 20m1/min. Extraction velocity of chromium ion increased with increasing difference of hydrogen ion concentraction of dispersion and continuous phase and column stage decreased.

• Steel and Composite Structures
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• v.42 no.3
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• pp.363-373
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• 2022

This paper presents an experimental and a numerical investigation of a H-beam - composite box column joint fabricated with two new inner diaphragms and a continuous inner diaphragm. The main objective of the current research project is to investigate the structural performance of the newly developed inner diaphragms under a cyclic loading protocol. Hysteretic behaviour of the composite joints is analysed to investigate the structural performance of the new and continuous inner diaphragms. This paper compares the result of the finite element (FE) models with the new and continuous inner diaphragms against their counterpart experimental results. To produce a design criterion for the newly developed inner diaphragms, yielding or failure area of the inner diaphragms under tensile stress is analysed from the FE results.

• Journal of Korean Society of Steel Construction
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• v.25 no.6
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• pp.635-647
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• 2013

PSRC composite column is a concrete encased steel angle column. In the PSRC composite column, the steel angles placed at the corner of the cross-section resists bending moment and compression load. In the present study, using the performance criteria in KBC 2009, cyclic lateral loading test was performed for PSRC columns to verify the seismic performance. The test parameters were the column type, the use of continuous hoop, and the use of studs for steel angle. 2/3 scale specimens of a conventional composite column and three PSRC columns were tested. The test results showed that the load-carrying capacity predicted by KBC 2009 correlated well with the test results. The specimens also exhibited good deformation and energy dissipation capacities. After concrete cover spalling under cyclic loading, the load-carrying capacity were decreased by buckling of longitudinal bars and steel angles. When continuous hoop was used, the deformability of the PSRC column was improved, preventing early buckling of the steel angles.