• Korean Journal of Construction Engineering and Management
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• v.13 no.5
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• pp.25-34
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• 2012

It has been five years since the Post-Construction Sale System of Housing was introduced. The purpose of this study is to identify objectives and effects of the Post-Construction Sale System of Housing and analyze change of profitability at different sales time from a supplier's point of view. Apartment buildings construction projects performed in Seoul are used for the case study. The present value of sales revenues, sensitivity and the present value of expected sales prices are analyzed. According to the findings, first, profits made from a Pre-construction sales system was 5.1%~6.2% higher than those from a Post-construction sales system. Among four plans of a Pre-construction sales system (A, B, C and D plan), sales revenue from the A plan, which takes a deposit at the time of starting construction, was the greatest. Second, increase of the rate of discount and decrease of sales revenues are in direct proportion. The bigger rate of discount leads actual reduction of sales revenues. Third, for the present value of sales revenues reflecting change in basic model construction cost, a Pre-construction sales system showed a little higher than that of a Post-construction sales system by approximately 2%. It should be known that this study suggests profitability of Pre-and Post-construction sales system by clearly measuring them in the supplier's point of view and calculates sales revenues, considering change of a sale price following change of sales time.

• Journal of Convergence for Information Technology
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• v.7 no.4
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• pp.105-111
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• 2017

With the emergence of the fourth industrial revolution, more and more attempts have been made to apply IoT technology to the manufacturing process and launch the product. In this paper, we propose IoT authentication scheme based on hash chain which can easily apply IoT device to small and medium enterprises in Korea. In the proposed method, the companies that installed IoT devices suitable for the manufacturing environment are selected to maintain the linkage between IoT devices so that product information and release information can be efficiently collected and managed during the entire manufacturing process. In addition, the proposed scheme is characterized in that it does not require an additional encryption / decryption algorithm because the authentication information of the IoT device is constructed based on a hash chain. As a result of the performance evaluation, the efficiency of the manufacturing process was improved by 18.5% and the processing of the manufacturing process with the IoT device was shortened by 20.1% on the average according to the application of the IoT device. In addition, the labor cost reduction costs in the manufacturing process decreased by an average of 30.7%.

• Journal of Korea Water Resources Association
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• v.39 no.5 s.166
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• pp.405-415
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• 2006

The deposition of sewer solids during dry weather in combined sewer systems results in a loss of flow capacity that may restrict flow and cause a local flooding and enhanced solids deposition. Sewer solid accumulations in drainage systems also create the 'first-flush' phenomena during wet weather runoff periods. In order to solve these problems, measurement of these loadings for a given sewer system for extended period is needed but this task is very difficult and extremely expensive. In this study, generalized procedures for estimating sewer sediment solid during dry weather in combined sewer systems developed by the U. S. Environmental Protection Agency were applied in a drainage system in Korea. As result, the appropriate equation can be selected and applied according to the available data. However, the estimated solid sediment shows considerable difference between methods which classified by model and estimation methods of variable. The estimated values using equations (1) $\sim$ (4) are greater than that of equations (5) $\sim$ (9) and intermediate models show greater values than elaborate or simplest models. The comparison between simulated and measured solid deposition is difficult due to the absent of measurement data, but this estimation method can be used usefully for the management of sewer solid with reduction of cost and effort if the measurement is carried out and the equation is adjusted according to the actual drainage systems in Korea.

• Journal of Korean Society of Transportation
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• v.27 no.5
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• pp.97-111
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• 2009

Image-based traffic information collection systems have entered widespread adoption and use in many countries since these systems are not only capable of replacing existing loop-based detectors which have limitations in management and administration, but are also capable of providing and managing a wide variety of traffic related information. In addition, these systems are expanding rapidly in terms of purpose and scope of use. Currently, the utilization of image processing technology in the field of traffic accident management is limited to installing surveillance cameras on locations where traffic accidents are expected to occur and digitalizing of recorded data. Accurately recording the sequence of situations around a traffic accident in a signal intersection and then objectively and clearly analyzing how such accident occurred is more urgent and important than anything else in resolving a traffic accident. Therefore, in this research, we intend to present a technology capable of overcoming problems in which advanced existing technologies exhibited limitations in handling real-time due to large data capacity such as object separation of vehicles and tracking, which pose difficulties due to environmental diversities and changes at a signal intersection with complex traffic situations, as pointed out by many past researches while presenting and implementing an active and environmentally adaptive methodology capable of effectively reducing false detection situations which frequently occur even with the Gaussian complex model analytical method which has been considered the best among well-known environmental obstacle reduction methods. To prove that the technology developed by this research has performance advantage over existing automatic traffic accident recording systems, a test was performed by entering image data from an actually operating crossroad online in real-time. The test results were compared with the performance of other existing technologies.

• Journal of Food Hygiene and Safety
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• v.33 no.2
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• pp.89-93
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• 2018

High sodium dietary habits may cause various diseases, thereby threatening the public health. Various efforts have been made to control high sodium use in diets, but few studies have been conducted on health communication efforts to modify such habits. This study looks for suggestions for diet improvement education by examining whether or not high sodium dietary habits can be predicted by a consumer's perception on the threat and controllability of high sodium diets. In this study, a questionnaire was developed to measure the severity, vulnerability, efficiency, efficacy, and behavioral tendencies of the consumer, which were subscales of the protective motivation theory. The questionnaire was given to university students and their families in Chungnam Province. The results of a statistical analysis were as follows: First, more young people preferred high-sodium diets than older people. Second, the correlation analysis showed that older people knew that they were vulnerable to the negative effects of high sodium diets, but they would not change their dietary habits until they were confident that they could control the high-sodium diet. Third, the structural model analysis showed that the higher the coping perception was, the lower was the tendency to consume a high-sodium diet. These results suggest that in the effort to reduce high-sodium diets, it is more effective to provide viable information and improve efficacy.

• Journal of Korean Neurosurgical Society
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• v.29 no.4
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• pp.461-470
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• 2000

Objective : Many investigators have demonstrated the protective effects of hypothermia following traumatic brain injury(TBI) in both animals and humans. It has long been recognized that mild to moderate hypothermia improves neurologic outcomes as well as reduces histologic and biochemical sequelae after TBI. In this study, two immunohistochemical staining using terminal deoxynucleotidyl-transferase-mediated biotin dUTP nick end labeling(TUNEL), staining of apoptosis, and ${\beta}$-amyloid precursor protein(${\beta}$-APP), a marker of axonal injury, were done and the authors evaluated the protective effects of hypothermia on axonal and neuronal injury after TBI in rats. Material and Method : The animals were prepared for the delivery of impact-acceleration brain injury as described by Marmarou and colleagues. TBI is achieved by allowing of a weight drop of 450gm, 1 m height to fall onto a metallic disc fixed on the intact skull of the rats. Fourty Sprague-Dawley rats weighing 400 to 450g were subjected to experimental TBI induced by an impact-acceleration device. Twenty rats were subjected to hypothermia after injury, with their rectal temperatures maintained at $32^{\circ}C$ for 1 hour. After this 1-hour period of hypothermia, rewarming to normothermic levels was accomplished over 30-minute period. Following 12 hours, 24 hours, 1 week and 2 weeks later the animals were killed and semiserial sagittal sections of the brain were reacted for visualization of the apoptosis and ${\beta}$-APP. Results : The density of ${\beta}$-APP marked damaged axons within the corticospinal tract at the pontomedullary junction and apoptotic cells at the contused cerebral cortex were calculated for each animal. In comparison with the untreated controls, a significant reduction in ${\beta}$-APP marked damaged axonal density and apoptotic cells were found in all hypothermic animals(p<0.05). Conclusion : This study shows that the posttraumatic hypothermia result in substantial protection in TBI, at least in terms of the injured axons and neurons.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.88-96
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• 2020

It were found that the heavyweight waste glass can be used as a construction materials including concrete from previous experimental studies. In this study, in order to evaluate the structural behavior of RC members using heavyweight waste glass as fine aggregate, a flexural behavior test was performed. And then, its results were compared with those obtained from non-linear finite element model analysis. From the results, when the heavyweight waste glass as fine aggregate in RC member, the area of compressive crushing and the number of cracks increased, however, the mean of cracking spacing decreased. Also it had reduced the ductility at high loading stage. For this reason, the same analysis method about the RC member using natural sand as fine aggregate did not predict the initial stiffness, yield load and maximum load on the flexural behavior of the RC members using heavyweight waste glass as fine aggregate. On the other hand, when it is analytically implemented the reduction of neutral axis depth due to developed compression crushing, the results of non-linear finite element analysis could be predicted the experimental results, relatively well.

• Laboraroty Animal Research
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• v.34 no.4
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• pp.166-175
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• 2018

Recombination activating gene-2 (RAG-2) plays a crucial role in the development of lymphocytes by mediating recombination of T cell receptors and immunoglobulins, and loss of RAG-2 causes severe combined immunodeficiency (SCID) in humans. Rag-2 knockout mice created using homologous recombination in ES cells have served as a valuable immunodeficient platform, but concerns have persisted on the specificity of Rag-2-related phenotypes in these animals due to the limitations associated with the genome engineering method used. To precisely investigate the function of Rag-2, we recently established a new Rag-2 knockout FVB mouse line ($Rag-2^{-/-}$) manifesting lymphopenia by employing a CRISPR/Cas9 system at Center for Mouse Models of Human Disease. In this study, we further characterized their phenotypes focusing on histopathological analysis of lymphoid organs. $Rag-2^{-/-}$ mice showed no abnormality in development compared to their WT littermates for 26 weeks. At necropsy, gross examination revealed significantly smaller spleens and thymuses in $Rag-2^{-/-}$ mice, while histopathological investigation revealed hypoplastic white pulps with intact red pulps in the spleen, severe atrophy of the thymic cortex and disappearance of follicles in lymph nodes. However, no perceivable change was observed in the bone marrow. Moreover, our analyses showed a specific reduction of lymphocytes with a complete loss of mature T cells and B cells in the lymphoid organs, while natural killer cells and splenic megakaryocytes were increased in $Rag-2^{-/-}$ mice. These findings indicate that our $Rag-2^{-/-}$ mice show systemic lymphopenia with the relevant histopathological changes in the lymphoid organs, suggesting them as an improved Rag-2-related immunodeficient model.

• Journal of Korean Tunnelling and Underground Space Association
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• v.20 no.6
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• pp.1147-1159
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• 2018

This study focuses on the verification of a rapid protection automation system using an inflatable structure. The inflatable structure is an automatic rapid protection system against human and material damage when the subsea tunnel is flooded. Especially, it is essential for construction and operation of subsea tunnels. In this study, we have experimentally verified the rapid protection automation system using the inflatable structure designed for this problem. In order to verify this, a model tunnel with a 40: 1 reduction ratio was constructed, and air pressure of 0.1 bar and 0.15 bar was injected to divide the tunnel according to the expansion rate at 10 sec and 20 sec. According to the results of the study, the protection efficiency was better at 0.15 bar than 0.1 bar when the expansion structure was expanded, and the protection efficiency and influent control efficiency were different according to the pneumatic injection time of the inflating structure. As a result of this study, it was found that the higher the internal air pressure of the inflated structure and the faster the inflation of rate, the more effectively the inflated structure was inflated. As a result of this study, it is necessary to further study the wedge type structure which is useful for the storage method of expansion structure, shape and expansion derivative, inhibition of expansion structure during protection and control of inflow water.

• Herbal Formula Science
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• v.26 no.4
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• pp.295-306
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• 2018

Schisandra chinensis (SC) and Lycium chinense (LC) were widely distributed in Asia and the fruit has been used traditionally for medicinal herbs. The processing method was solid-state fermentation using Aspergillus oryzae for 48 h after stir-frying treatment at $220^{\circ}C$ for 12 min. In this study, in vitro the anti-inflammatory effect and in vivo hangover reduction were compared to unprocessed SC and LC water extract. Anti-inflammatory effects have been evaluated in pro-inflammatory mediators which were secreted by lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Nitric oxide (NO) was determined using Griess reaction. Proinflammatory cytokines such as tumor necrosis factor $(TNF)-{\alpha}$ and interleukin $(IL)-1{\beta}$ were measured by enzyme-linked immunosorbent assays (ELISA). Alcohol dehydrogenase (ADH) and acetaldehyde dehydrogenase (ALDH) activities were compared to processed SC or LC and mixtures thereof (1:1). In vivo study was compared to hangover relief in alcohol-fed mice. After administering a mixture of SC and LC (300 mg/kg) water extract (1:1), mice were fed 3 g/kg of ethanol. Serum was collected at 1, 3, and 5 h intervals to analyze ethanol and acetaldehyde levels using a colorimetric assay kit. The processed SC and LC water extracts compared to raw materials significantly inhibited LPS-induced NO and inflammatory cytokine production in RAW 264.7 cells. The results of the hangover mouse model are also consistent with anti-inflammatory effects. These results suggest that processed SC and LC extracts may be functional materials for the treatment of inflammation and hangover.