• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1061-1071
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• 2018

A subsea tunnel, being a super-sized underground structure must ensure safety at the time of earthquake, as well as at ordinary times. At the time of earthquake, in particular, of a subsea tunnel, a variety of response behaviors are induced owing to relative rigidity to the surrounding ground, or difference of displacement, so that the behavior characteristics can be hardly anticipated. The investigation aims to understand the behavior characteristics switched by earthquake of an imaginary subsea tunnel which passes through a fault zone having different physical properties from those of the surrounding ground. In order to achieve the aim, dynamic response behaviors of a subsea tunnel which passes through a fault zone were observed by means of indoor experiments. For the sake of improved earthquake resistance, a shape of subsea tunnel to which flexible segments have been applied was considered. Afterward, it is believed that a D/B can be established through 3-dimensional earthquake resistance interpretation of various grounds, on the basis of verified results from the experiments and interpretations under various conditions. The present investigation performed 1 g shaking table test in order to verify the result of 3-dimensional earthquake resistance interpretation. A model considering the similitude (1:100) of a scale-down model test was manufactured, and tests for three (3) Cases were carried out. Incident seismic wave was introduced by artificial seismic wave having both long-period and short-period earthquake properties in the horizontal direction which is rectangular to the processing direction of the tunnel, so that a fault zone was modeled. For numerical analysis, elastic modulus of the fault zone was assumed 1/5 value of the modulus of individual grounds surround the tunnel, in order to simulate a fault zone. Resultantly, reduced acceleration was confirmed with increase of physical properties of the fault zone, and the result from the shaking table test showed the same tendency as the result from 3-dimensional interpretation.

• Journal of Life Science
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• v.8 no.3
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• pp.263-271
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• 1998

One of the better-characterized transcription factor of E. coli is the cAMP receptor protein(CRP) and the CRP binds cAMP and DNA. The cAMP-CRP complex is involved in regulation of many genes at bacteria. The cAMP-CRP regulatory element represents, in some respects, a global regulatory network. The aim of this work was to study the structure and the mechanisms controlling the expression of CRP in Serratia marcescens. We have been get 5 different clones from Serratia which stimulated the cells to use maltose as a sole carbon source in E. coli TP2139. The crp gene clone, pCKB12, was confirmed by Southern hybridization with E. coli crp gene. The location of the crp gene was determined by construction subclones carrying various portions of pCKB12. To investigate the potential role of CRP in E. coli, lacZ fused plasmids were constructed and investigated the ${\beta}$-galactosidase activity of the fused plasmid. The Serratiamarcescens cAMP receptor protein can substitute the E. coli CRP in transcriptional activation at the lacZ gene. These results suggest that Serratia marcescens cAMP receptor protein complex functions to regulate several promoters in E. coli.

• Animal Bioscience
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• v.37 no.2
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• pp.261-273
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• 2024

Objective: The objective of this study was to evaluate the growth performance, rumen fermentation parameters and bacterial community of post-weaning dairy calves in response to five diets varying in corn silage (CS) inclusion. Methods: A total of forty Holstein weaned bull calves (80±3 days of age;128.2±5.03 kg at study initiation) were randomized into five groups (8 calves/group) with each receiving one of five dietary treatments offered as total mixed ration in a 123-d feeding study. Dietary treatments were control diet (CON; 0% CS dry matter [DM]); Treatment 1 (T1; 27.2% CS DM); Treatment 2 (T2; 46.5% CS DM); Treatment 3 (T3; 54.8% CS DM); and Treatment 4 (T4; 67.2% CS DM) with all diets balanced for similar protein and energy concentration. Results: Results showed that calves offered CS had greater average daily gain, body length and chest depth growth, meanwhile altered rumen fermentation indicated by decreased rumen acetate concentrations. Principal coordinate analysis showed the rumen bacterial community structure was affected by varying CS inclusion diets. Bacteroidetes and Firmicutes were the predominant bacterial phyla in the calf rumens across all treatments. At the genus level, the abundance of Bacteroidales_RF16_group was increased, whereas Unclassified_Lachnospiraceae was decreased for calves fed CS. Furthermore, Spearman's correlation test between the rumen bacteria and rumen fermentation parameters indicated that Bacteroidales_RF16_group and Unclassified Lachnospiraceae were positively correlated with propionate and acetate, respectively. Conclusion: The results of the current study suggested that diet CS inclusion was beneficial for post-weaning dairy calf growth, with 27.2% to 46.5% CS of diet DM recommended to achieve improved growth performance. Bacteroidales_RF16_group and Unclassified Lachnospiraceae play an important role in the rumen fermentation pattern for post-weaning calves fed CS.

• Journal of Dental Rehabilitation and Applied Science
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• v.34 no.4
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• pp.297-305
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• 2018

Purpose: This study aimed to analyze stress distribution and maximum von Mises stress generated in intracoronal restorations and in tooth structures of mandibular molars with various types of cavity designs and materials. Materials and Methods: Three-dimensional solid models of mandible molar such as O inlay cavity with composite and gold (OR-C, OG-C), MO inlay cavity with composite and gold (MR-C, MG-C), and minimal invasive cavity on occlusal and proximal surfaces (OR-M, MR-M) were designed. To simulate masticatory force, static axial load with total force of 200 N was applied on the tooth at 10 occlusal contact points. A finite element analysis was performed to predict stress distribution generated by occlusal loading. Results: Restorations with minimal cavity design generated significantly lower values of von Mises stress (OR-M model: 26.8 MPa; MR-M model: 72.7 MPa) compared to those with conventional cavity design (341.9 MPa to 397.2 MPa). In tooth structure, magnitudes of maximum von Mises stresses were similar among models with conventional design (372.8 - 412.9 MPa) and models with minimal cavity design (361.1 - 384.4 MPa). Conclusion: Minimal invasive models generated smaller maximum von Mises stresses within restorations. Within the enamel, similar maximum von Mises stresses were observed for models with minimal cavity design and those with conventional design.

• Korean Journal of Environment and Ecology
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• v.38 no.2
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• pp.189-203
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• 2024

This study conducted a survey two times at 20 points from April to June and from August to October 2022 to characterize the fish community and reveal the health of the Anyang stream. The survey collected 3,186 individuals belonging to 5 orders, 10 families and 34 species. The dominant species was Zacco platypus (43.4%), followed by Carassius auratus (10.1%), Cyprinus carpio (7.6%), Zacco koreanus (6.2%), Pungtungia herzi (5.2%), Oryzias sinensis (5.1%), Pseudorasbora parva (4.7%), Squalidus gracilis majimae (4.4%), Rhynchocypris oxycephalus (3.5%), Hemiculter eigenmanni (3.3%), Rhodeus ocellatus (1.4%), and Chelon haematocheilus (1.0%). Among the emerged species, 5 species (14.7%), including Rhodeus uyekii, Squalidus japonicus coreanus, and Odontobutis interrupta, were endemic to Korea, and 4 species (11.8%), including Cyprinus carpio (Israeli type), Lepomis macrochirus, Micropterus salmoides, and Poecilia reticulata, were exotic. The fish community analysis showed that the dominance was higher at the upper reaches of the Anyang stream and decreased downstream, and diversity, richness, and evenness were higher in tributary than mainstream. Stream health (fish assessment index, FAI) was generally poor, as it was rated as moderate (C) at seven sites, poor (D) at eight sites, and very poor (E) at five sites. Water quality was evaluated at eight sites, and it was rated as poor (V) at two sites, slightly poor (IV) at one site, moderate (III) at four sites, and slightly good (II) at one site, indicating that the overall water quality was poor and that the water quality had a significant impact on river health and fish habitat. Moreover, it was found that many weirs without fishways were constructed in the Anyang stream and became an obstacle to fish migration. Therefore, a systematic management plan to improve water quality and add fishways is necessary to improve the stream's health and conserve stable fish habitat.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.8
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• pp.4068-4076
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• 2013

The wheel-rail interaction forces are influenced by the velocity of vehicle, wheel load, alignment (curve radius, cant etc). For the safety of track structure, it is required to evaluate the influences for track and influential factors. Recently, the HEMU 430-X, which was developed by Next Generation High-Speed Rail Development R&D Project, achieved 421.4km/h in a test run of Daegu.Busan section of the Gyeongbu high speed rail on March in 2013. In the case of additional speed-up test on Test-Bed Section(Gongju.Jeongeup: KP 100~128km Osong starting point), the analysis of track forces is required for outer rail by the increase of dynamic force and centrifugal force of vehicle. In this paper, the vehicle speed variation on HSL line is evaluated by TPS analysis considering the tractive effort of HEMU 430-X, tested running resistance and alignment of Honam HSR. And the track forces are evaluated by centrifugal force and impact factor on curved track.

• Journal of Korean Physical Therapy Science
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• v.13 no.4
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• pp.43-62
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• 2006

The survey was conducted with participation of the 289 handicapped persons residing at the rural area OOeup-gun in Kyungbook for the period of March 2 - May 31, 2006, to study the nature in general of the handicapped and the boundaries of their need. For the nature in general of the handicapped, the study was done by gender iscrimination, age, marital status, religion, educational level, occupation, monthly income, disability cause, disabled duration, disability type, disability level. For the boundaries of their need, the study was done by demand of financial support, educational demand, demand of voluntary workers, need of rehabilitation and medical treatment, job training, improvement of living conditions, or so. Using the Win.SPSS program, we made a frequency analysis and conclusions on the nature in general of the handicapped and the boundaries of their need on a 2-test. Conclusions are : 1. Nature in general of the handicapped The existence of the handicapped shows high at the age over 51 (71.6%), male-handicapped (65.1%), primary school graduates (62.9%), farming engaging (65.2%), monthly income less than one million Won (80.5%), cause by disease (53.8%), duration more than 10 years (61.6%), disability at level 3 (39.8%), extremity disability (66.4%). 2. Correlation of nature in general with demand of the handicapped a. In demanding the financial support, support for helper’s compensation shows high (p<0.05). In demanding the necessity of voluntary workers, the male-handicapped appears high during the absence of family assistance and the female-handicapped appears differently per week and also appears high during the absence of family assistance (p<0.05). b. In educational demand of the handicapped by their age, the age below 30 demands technical-job training and the age over 31 demands medical education for health care (p<0.01). c. In demanding the financial support by educational level, support for living cost shows high (p<0.05). d. In demanding improvement of living conditions by postnatal cause of disability, improvement of house structure shows high (p<0.05). e. In demanding assistance of voluntary workers by disabled duration, "No Need" shows high in the disabled duration more than 4 years (p<0.05). f. In demanding rehabilitation and medical treatment by disability type, home-visiting treatment, oriental medical treatment and physical therapy show high (p<0.001). g. In educational demand by disability level, medical education for health care shows high (p<0.01).

• Korean Chemical Engineering Research
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• v.60 no.3
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• pp.347-355
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• 2022

The safety valve (PSV) is a safety device that automatically releases a spring when the pressure generated by various causes reaches the set pressure, and is restored to a normal state when the pressure falls below a certain level. Periodic inspection and monitoring of safety valves are essential so that they can operate normally in abnormal conditions such as pressure rise. However, as the current safety inspection is performed only at a set period, it is difficult to ensure the safety of normal operation. Therefore, evaluation items were developed by finding failure modes and causative factors of safety valves required for safety management. In addition, it is intended to provide decision-making information for securing safety by deriving the priority of items. To this end, a Delphi survey was conducted three times to derive evaluation factors that were judged to be important in relation to the Failure Mode Cause Factor (FMCFs) of the safety valve (PSV) targeting 15 experts. As a result, 6 failure modes of the safety valve and 22 evaluation factors of its sub-factors were selected. In order to analyze the priorities of the evaluation factors selected in this way, the hierarchical structure was schematized, and the hierarchical decision-making method (AHP) was applied to the priority calculation. As a result of the analysis, the failure mode priorities of FMCFs were 'Leakage' (0.226), 'Fail to open' (0.201), 'Fail to relieve req'd capacity' (0.152), 'Open above set pressure' (0.149), 'Spuriously' 'open' (0.146) and 'Stuck open' (0.127) were confirmed in the order. The lower priority of FMCFs is 'PSV component rupture' (0.109), 'Fail to PSV size calculation' (0.068), 'PSV Spring aging' (0.065), 'Erratic opening' (0.059), 'Damage caused by improper installation and handling' (0.058), 'Fail to spring' (0.053), etc. were checked in the order. It is expected that through efficient management of FMCFs that have been prioritized, it will be possible to identify vulnerabilities of safety valves and contribute to improving safety.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.88-89
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• 2013

A variety of influenza A viruses from animal hosts are continuously prevalent throughout the world which cause human epidemics resulting millions of human infections and enormous industrial and economic damages. Thus, early diagnosis of such pathogen is of paramount importance for biomedical examination and public healthcare screening. To approach this issue, here we propose a fully integrated Rotary genetic analysis system, called Rotary Genetic Analyzer, for on-site detection of influenza A viruses with high speed. The Rotary Genetic Analyzer is made up of four parts including a disposable microchip, a servo motor for precise and high rate spinning of the chip, thermal blocks for temperature control, and a miniaturized optical fluorescence detector as shown Fig. 1. A thermal block made from duralumin is integrated with a film heater at the bottom and a resistance temperature detector (RTD) in the middle. For the efficient performance of RT-PCR, three thermal blocks are placed on the Rotary stage and the temperature of each block is corresponded to the thermal cycling, namely $95^{\circ}C$ (denature), $58^{\circ}C$ (annealing), and $72^{\circ}C$ (extension). Rotary RT-PCR was performed to amplify the target gene which was monitored by an optical fluorescent detector above the extension block. A disposable microdevice (10 cm diameter) consists of a solid-phase extraction based sample pretreatment unit, bead chamber, and 4 ${\mu}L$ of the PCR chamber as shown Fig. 2. The microchip is fabricated using a patterned polycarbonate (PC) sheet with 1 mm thickness and a PC film with 130 ${\mu}m$ thickness, which layers are thermally bonded at $138^{\circ}C$ using acetone vapour. Silicatreated microglass beads with 150~212 ${\mu}L$ diameter are introduced into the sample pretreatment chambers and held in place by weir structure for construction of solid-phase extraction system. Fig. 3 shows strobed images of sequential loading of three samples. Three samples were loaded into the reservoir simultaneously (Fig. 3A), then the influenza A H3N2 viral RNA sample was loaded at 5000 RPM for 10 sec (Fig. 3B). Washing buffer was followed at 5000 RPM for 5 min (Fig. 3C), and angular frequency was decreased to 100 RPM for siphon priming of PCR cocktail to the channel as shown in Figure 3D. Finally the PCR cocktail was loaded to the bead chamber at 2000 RPM for 10 sec, and then RPM was increased up to 5000 RPM for 1 min to obtain the as much as PCR cocktail containing the RNA template (Fig. 3E). In this system, the wastes from RNA samples and washing buffer were transported to the waste chamber, which is fully filled to the chamber with precise optimization. Then, the PCR cocktail was able to transport to the PCR chamber. Fig. 3F shows the final image of the sample pretreatment. PCR cocktail containing RNA template is successfully isolated from waste. To detect the influenza A H3N2 virus, the purified RNA with PCR cocktail in the PCR chamber was amplified by using performed the RNA capture on the proposed microdevice. The fluorescence images were described in Figure 4A at the 0, 40 cycles. The fluorescence signal (40 cycle) was drastically increased confirming the influenza A H3N2 virus. The real-time profiles were successfully obtained using the optical fluorescence detector as shown in Figure 4B. The Rotary PCR and off-chip PCR were compared with same amount of influenza A H3N2 virus. The Ct value of Rotary PCR was smaller than the off-chip PCR without contamination. The whole process of the sample pretreatment and RT-PCR could be accomplished in 30 min on the fully integrated Rotary Genetic Analyzer system. We have demonstrated a fully integrated and portable Rotary Genetic Analyzer for detection of the gene expression of influenza A virus, which has 'Sample-in-answer-out' capability including sample pretreatment, rotary amplification, and optical detection. Target gene amplification was real-time monitored using the integrated Rotary Genetic Analyzer system.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.642-650
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• 2020

In general, the circulation path of the fluidized particles in a CFB (Circulating Fluidized Bed) boiler is such that the particles entrained from a combustor are collected by a cyclone and recirculated to the combustor via a sealpot which is one of non-mechanical valves. However, when a fluidized bed heat exchanger (FBHE) is installed to additionally absorb heat from the fluidized particles, some particles in the sealpot pass through the FBHE and then flow into the combustor. At this time, in the FBHE operated in the bubbling fluidization regime, if the heat flow is not evenly distributed by poor mixing of the hot particles (800~950 ℃) flowing in from the sealpot, the heat exchanger tubes would be locally heated and then damaged, and the agglomeration of particles could also occur by formation of hot spot. This may affect the stable operation of the circulating fluidized bed. In this study, the unevenness of heat flow arising from structural problems of the FBHE of the domestic D-CFB boiler was found through the operating data analysis and the CPFD (Computational Particle Fluid Dynamics) simulation using Barracuda VR. Actually, the temperature of the heat exchanger tubes in the FBHE showed the closest correlation with the change in particle temperature of the sealpot. It was also found that the non-uniformity of the heat flow was caused by channeling of hot particles flowing in from the sealpot. However, it was difficult to eliminate the non-uniformity even though the fluidizing velocity of the FBHE was increased enough to fluidize hot particles vigorously. When the premixing zone for hot particles flowing in from the sealpot is installed and when the structure is changed through the symmetrization of the FBHE discharge line for particles reflowing into the combustor, the particle mixing and the uniformity of heat flow were found to be increased considerably. Therefore, it could be suggested that the structural modification of the FBHE, related to premixing and symmetric flow of hot particles, is an alternative to reduce the non-uniformity of the heat flow and to minimize the poor particle mixing.