• Structural Engineering and Mechanics
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• v.25 no.6
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• pp.691-716
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• 2007

The purpose of the present work is to establish a method for predicting the location and depth of a crack in a circular cross section beam by only considering the frequencies of the cracked beam. An accurate knowledge of the material properties is not required. The crack location and size is identified by finding the point of intersection of pulsation ratio contour lines of lower vertical and horizontal modes. This process is presented and numerically validated in the case of a simply supported beam with various crack locations and sizes. If the beam has structural symmetry, the identification of crack location is performed by adding an off-center placed mass to the simply supported beam. In order to avoid worse diagnostic, it was demonstrated that a robust identification of crack size and location is possible if two tests are undertaken by adding the mass at the left and then right end of the simply supported beam. Finally, the pulsation ratio contour lines method is generalized in order to be extended to the case of rectangular cross section beams or more complex structures.

• Steel and Composite Structures
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• v.23 no.4
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• pp.465-472
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• 2017

This paper presents an experimental study, investigating the compressive behavior of glass-fibre reinforced and unreinforced cementitious material-filled square steel tubular (GFCMFST and CMFST) columns. The specimens were manufactured by using high performance cementitious materials without using coarse aggregate. The influence of adding glass-fibres to the mix on the behavior of both axially and eccentrically loaded columns is considered. It was found that adding glass fibre improvesthe confinement behavior, the axial compressive strength, the stiffness and the toughness of both axially and eccentrically loaded columns. The compressive strength of axially loaded columns is compared with strength predictions according to EC4 and the AISC specification. It was found that the design predictions according to EC4 and the AISC codes provide conservative results for CMFST and GFCMFST columns. Alternatively, the axial load-bending moment interaction diagrams specified in theEC4 are conservative for the eccentrically tubular CMFST and GFCMFST tested columns.

• Journal of Korea Multimedia Society
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• v.22 no.7
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• pp.804-814
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• 2019

The patient's waiting time and length of stay have been reported as a factor decreasing their satisfaction in the hospital, especially in developing countries. This paper focuses on modeling hospital's outpatient department workflow in a developing country and optimizing the patient waiting time as well as total length of stay. By using discrete-event simulation, many alternative scenarios have raised, such as adding more working time, altering human resources, and adjusting the staff's responsibility, those scenarios will be examined to explore better settings for the hospital. The results show that possible to achieve a 9.6% reduction in patient total length of stay and it could be accomplished without adding more resources to the hospital.

• Structural Engineering and Mechanics
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• v.86 no.3
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• pp.325-336
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• 2023

A significant component of many civil constructions such as buildings, reservoirs, bridges, and sports halls, concrete has become increasingly popular due to its versatile properties. Concrete's internal characteristics change due to the use of different types of fibers, including changes in its microstructure, volume, and hole dimensions. Additionally, the type, dimensions, and distribution of fibers in concrete can affect the results of flexural strength tests by affecting its compressive and tensile strength. Due to a lack of information, fiber concrete is a new composite material in the production industry that requires laboratory studies to determine its behavior. This study investigated the bending behavior of multilayer slabs made of concrete reinforced by polyamide-propylene fibers against impact in weight lifting exercises. Results showed that adding fibers to concrete slab samples improved the mechanical properties while replacing them hurt the mechanical properties and failure of polymer fiber-reinforced concrete. On the other hand, adding and replacing fibers increases durability and has a positive effect.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.2
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• pp.136-144
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• 1997

Usually triangular patches are used to transfer geometric shape in Rapid Prototyping CAM system. STL, a list of triangles, is de facto standard in RP industry. Because STL does not have topological infoma- tion, it can cause errornous results. So STL should be verified before using. After adding support structures to anchor the part to the platform and to prevent sagging or distortion, slicing and layer by layer manufactur- ing process are done. But triangular patch is surface model and cannot provide sufficient information on geometry in the above processes. So, geometric modeling is necessary in verifying STL, adding support structures and slicing. It is natural that triangle based modeling is the best when tringular patches are used as input. Considering support structures, solid and faces coexist in RP process. Therefore non-manifold modeler is required. In this study, triangle based non-manifold geometric modeling is proposed for RP sys- tem consistent with STL input.

• Korean Journal of Agricultural Science
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• v.13 no.1
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• pp.130-138
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• 1986

In order to obtain the basic data for development of raw pepper homogenates as instant spice, effects of preservatives, packaging materials, storage temperature and period on chemical components of raw pepper homogenates were investigated during storage after sealing up. The results are as follows: 1. Raw pepper homogenates added 15% sodium chloride was effective prominently than raw pepper homogenates on residual contents of acidity, capsanthin and capsaicin. 2. P. V. D. C film was effective than P. E film in sealing of raw pepper homogenates. 3. Decomposition of capsanthin was exceeded at high temperature during the sealed storage of raw pepper homogenates and decomposition of capsaicin was accelerated at initial stage of storage and also it was decreased prominently by adding of sodium chloride. 4. Decomposition of vitamin C during the storage was exceeded at high temperature and it was prominently suppressed by adding of sodium chloride. 5. Increase of total viable cell count and lactic acid bacteia count was prominently suppressed by adding of sodium chloride and its difference for storage temperature was disregarded.

• Nutritional Sciences
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• v.6 no.4
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• pp.216-222
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• 2003

This study investigated the effects of feeding mulberry leaf extracts on lipid composition in rats fed high cholesterol diets. An initial 30-person sensory evaluation of preparations containing various concentrations of mulberry leaf extract showed that a preparation containing 9% mulberry leaf extracts was the most highly preferred. In addition, subsidiary materials of pine needle extracts and mugwort extracts were added to weaken the unpleasant smell of mulberry leaf extract A preparation containing 9% mulberry leaf extract with 3% mugwort extract and 7% pine needle extract was given highest preference scores by the 30-person panel. When comparing the functional ingredients contents of the various preparations of mulberry leaf extracts, such as GABA, DNJ and flavonoids, no significant differences were found as a result of adding subsidiary materials (pine needle and mugwort extracts). Sprague-Dawley male rats weighing l00$\pm$10g were randomly assigned to one normal diet group, and to four high cholesterol diet groups containing 1% cholesterol, to elucidate the functionality of the mulberry leaf extract The four high cholesterol diet groups were classified into: a mulberry leaf extract diet group free of subsidiary materials (EB group); a mulberry extract diet group with pine needle extracts (EP group); a mulberry leaf extract diet group with mugwort extracts (EM group); and a control group (HC group). The mulberry leaf extracts were provided as drinking water; the diet and water were fed ad libitum. Hepatic cholesterol and triglyceride levels were higher, by 279% to 475%, in the high cholesterol groups compared to the normal diet groups, but were significantly lower in the three groups supplied with mulberry leaf extracts, compared with the high cholesterol control. There were no changes in functionality of the mulberry leaf extract preparations due to the addition of subsidiary materials. In conclusion, preparations of mulberry leaf extracts were shown to improve lipid metabolism in rats fed a high cholesterol diet, by reducing hepatic and plasma triglyceride and cholesterol levels. Also human palatability of the mulberry leaf preparation was improved by adding subsidiary materials such as pine needle and mugwort extracts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.10
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• pp.1698-1702
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• 2004

The effects of glucono delta-lactone on the Quality of cooked rice were investigated. Cooked rice was prepared with the addition of acetic acid (AA) and glucono delta-lactone (GDL). Microbial population and textural properties were determinated during the storage periods at 3$0^{\circ}C$. The addition of AA and GDL above 0.1% was effective in the inhibition of bacterial growth for 72 hrs at 3$0^{\circ}C$. Lightness increased by addition of AA and GDL, but yellowness decreased. Hardness was significantly increased by adding AA and GDL, and also stickiness decreased by adding AA. Whereas, stickiness of cooked rice adding GDL increased significantly as the content of GDL increased. The present results confirmed that GDL was a useful food additive to extend the shelf-life and improve the Quality of cooked rice.

• Food Science of Animal Resources
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• v.34 no.4
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• pp.415-422
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• 2014

Duck feet gelatin (DFG) gel was added as a fat replacer to low-fat frankfurters and the effect of DFG on physicochemical, textural, and sensory characteristics of low-fat frankfurters was evaluated. DFG gel was prepared with a 20% duck feet gelatin concentration (w/w). Adding DFG decreased lightness and increased yellowness of the low-fat frankfurters (p<0.05). However, DFG did not affect redness of low-fat frankfurters (p>0.05). The statistical results indicated that adding DFG improved cooking yield of low-fat frankfurters (p<0.05). In addition, replacing pork back fat with DFG resulted in increased moisture content, protein content, and ash content of low-fat frankfurters, and the low-fat frankfurter formulated with 5% pork back fat and 15% DFG gel had the highest moisture content and lowest fat content (p<0.05). Adding of DFG increased all textural parameters including hardness, springiness, cohesiveness, chewiness, and gumminess of low-fat frankfurters (p<0.05). In terms of sensory properties, the low-fat frankfurter formulated with 5% pork back fat and 15% DFG gel showed similar satisfaction scores for the flavor, tenderness, juiciness, and overall acceptance when compared to the regular frankfurters (20% back fat). Therefore, our results suggest that DFG could be an effective novel source, as a fat replacer, for manufacturing of low-fat frankfurters.

• Food Science of Animal Resources
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• v.31 no.3
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• pp.389-397
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• 2011

This study was conducted to examine the effect of salt concentration in soybean sauce (ganjang) on pre-rigor ground Hanwoo (Korean native cattle) muscle. Although adding soybean sauce reduced pH of pre-rigor Hanwoo muscle, it improved the water holding capacity (WHC), cooking loss, total protein solubility, myofibrillar fragmentation index (MFI), 2-thiobar-bituric acid (TBA) values, and textural properties by increasing salt concentration in the soybean sauce. In particular, adding soybean sauce inhibited lipid oxidation despite increasing salt concentration. An increased salt concentration in the soybean sauce in pre-rigor Hanwoo muscle tended to make the meat have lower lightness and higher redness and yellowness values. Although soybean sauce had a significantly lower pre-rigor salting effect than sodium chloride in terms of cooking loss and total protein solubility (p<0.05), soybean sauce improved myofibrillar fragmentation and lipid oxidation when compared with sodium chloride. Furthermore, no significant differences in textural properties were observed between adding soybean sauce and sodium chloride at the same salt concentrations. Therefore, soybean sauce can be a functional curing material for pre-rigor muscle.