• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.2
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• pp.791-800
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• 2013

Needs for developing a better way of cost estimating process for public construction projects have been widely recognized. Those needs are mainly from the early phases of the project through the construction life cycle due to the its importance to the control process. In contrast to the traditional estimating method based on unit-price references, this research utilized this following process. The first step is analyzing the real cost data from actual cost activities (2000~2010) about the statement of P.S.C(Prestressed Concrete) Box Girder Bridge. The collected data was broken into four categories based on technical construction methods such as I.L.M(Incremental Launching Method), M.S.S(Movable Scaffolding System), F.S.M(Full Staging Method), and F.C.M(Free Cantilever Method). The second, actual design documents including the actual cost estimating documents, drawings and specifications were carefully reviewed to cluster the cost itemized statement from four categories. It was also attempted to seek the proper breakdown of standard works that are responsible for more than 95 percentage in each categories in terms of its cost. The third, this research comes up the index for standard unit materials and unit price of standard work and develops the approximate estimating model applying for the specification(length and breadth of bridges) per square area that the user takes as well as suggests the practical application plan within the original time alloted.

• Journal of Periodontal and Implant Science
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• v.37 no.4
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• pp.733-742
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• 2007

Bone morphogenetic proteins have been shown to possess significant osteoinSductive potential, but in order to take advantage of this effect for tissue engineering, carrier systems are essential. Successful carrier systems must enable vascular and cellular invasion, allowing BMP to act as a differentiation factor. The carrier should be reproducible, non-immunogenic, moldable, and space-providing, to define the contours of the resulting bone. The purpose of this study was to review available literature, in comparing various carriers of BMP on rat calvarial defect model. The following conclusions were deduced. 1. Bone regeneration of ACS/BMP, ${\beta}-TCP/BMP$, FFSS/BMP, $FFSS/{\beta}-TCP/BMP$, MBCP/BMP group were significantly greater than the control groups. 2. Bone density in the ACS/BMP group was greater than that in ${\beta}-TCP$, FFSS, $FFSS/{\beta}-TCP$ carrier group. 3. Bone regeneration in FFSS/BMP group was less than in ACS/BMP, ${\beta}-TCP/BMP$, MBCP/BMP group. However, New bone area of $FFSS/{\beta}-TCP/BMP$ carrier group were more greater than that of FFSS/BMP group. ACS, ${\beta}-TCP$, FFSS, $FFSS/{\beta}-TCP$, MBCP were used for carrier of BMP. However, an ideal carrier which was reproducible, non-immunogenic, moldable, and space-providing did not exist. Therefore, further investigation are required in developing a new carrier system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.222-225
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• 1993

To obtain a thermal diffusivity predicting equation for meat products, minced pork meat was mixed with some additives such as lard, isolated soybean protein, 1.5% of table salt and 2% of polyphosphate to control the composition and texture of the products and then stuffed in a model can. Heat penetration curves were measured in the temperature range of 80.76~121.03$^{\circ}C$ by using a thermocouple fixed at the cold point of the model can and the thermal diffusivities were calculated from the plotted heat penetration curves. At constant heating temperature, the thermal diffusivities of pork meat with water content of 49.01~77.55% increased linearly with increasing water content. The thermal diffusivities of the products with constant water content also increased linearly with increasing heating temperature and the values could be predicted by following equation: $\alpha$p=(2.1394+0.5X$_{w}$).$\alpha$$_{w}$+0.0035.10$^{-6}$ .X$_{w}$-0.2785.10$^{-6}$ ,(m$^2$.s$^{-1}$ ). The maximal difference of the values predicted with this equation on the basis of the practical measured values were less than 1.7%. 1.7%.

• Journal of vocational education research
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• v.30 no.4
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• pp.113-127
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• 2011

The study investigates the type of organizational culture, using the organizational culture assessment instrument(OCAI) developed by Cameron and Quinn based on the competing value model(CVM), and analyzed the gap between current and desirable organizational culture empirically. The analytic results show that while the organizational members prefer the relational organizational culture as a dominant organizational culture on the current level. Also they prefer the relational organizational culture as a desirable organizational culture on the future level. In addition, the diagnosis of organizational culture by the type of status reveals that while the public educational personnel and staff recognized the relational organizational culture as a strong culture, the local public service employee identified the hierarchical culture as a dominant culture on the current level. Those findings suggest the following implications. First, the sustainable management of organizational culture requires the suitable strategic tools. That is to say, they need to introduce and carry out practical strategies to sustain change and control for each type of organizational culture. Second, despite the fact that the balance among four types of organizational culture is needed the strategy to reinforce the dominant culture, considering the types of status and affiliation.

• Natural Product Sciences
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• v.27 no.2
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• pp.86-98
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• 2021

This study was designed to characterize the effect of ginsenoside-Rg2 (Rg2), one of panaxatriol saponins isolated from Korean ginseng root, on the release of catecholamines (CA) in the perfused model of the rat adrenal medulla, and also to establish its mechanism of action. Rg2 (3~30 µM), administered into an adrenal vein for 90 min, depressed acetylcholine (ACh)-induced CA secretion in a dose- and time-dependent manner. Rg2 also time-dependently inhibited the CA secretion induced by 3-(m-chloro-phenyl-carbamoyl-oxy)-2-butynyltrimethyl ammonium chloride (McN-A-343), 1.1-dimethyl-4-phenyl piperazinium iodide (DMPP), and angiotensin II (Ang II). Also, during perfusion of Rg2, the CA secretion induced by high K⁺, veratridine, cyclopiazonic acid, methyl-1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluoro-methyl-phenyl)-pyridine-5-carboxylate (Bay-K-8644) depressed, respectively. In the simultaneous presence of Rg2 and N^ω-nitro-L-arginine methyl ester hydrochloride ʟ-NAME), the CA secretion induced by ACh, Ang II, Bay-K-8644 and veratridine was restored nearly to the extent of their corresponding control level, respectively, compared to those of inhibitory effects of Rg2-treatment alone. Virtually, NO release in adrenal medulla following perfusion of Rg2 was significantly enhanced in comparison to the corresponding spontaneous release. Also, in the coexistence of Rg2 and fimasartan, ACh-induced CA secretion was markedly diminished compared to the inhibitory effect of fimasartan-treated alone. Collectively, these results demonstrated that Rg2 suppressed the CA secretion induced by activation of cholinergic as well as angiotensinergic receptors from the perfused model of the rat adrenal gland. This Rg2-induced inhibitory effect seems to be exerted by reducing both influx of Na⁺ and Ca²⁺ through their ionic channels into the adrenomedullary cells as well as by suppressing Ca²⁺ release from the cytoplasmic calcium store, at least through the elevated NO release by activation of NO synthase, which is associated to the blockade of neuronal cholinergic and AT₁-receptors. Based on these results, the ingestion of Rg2 may be helpful to alleviate or prevent the cardiovascular diseases, via reduction of CA release in adrenal medulla and consequent decreased CA level in circulation.

• Journal of Applied Biological Chemistry
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• v.64 no.2
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• pp.165-170
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• 2021

In this study, the antioxidant effects of mineral-containing deep sea water (DSW) on kidney function was confirmed using a cell model. DSW samples were prepared with different mineral concentrations including calcium and magnesium-the main minerals found in DSW-to derive the following sample groups: trace minerals (TM), high magnesium (HM), high magnesium, low salt (HMLS) and high magnesium, high calcium (HMHC). The purpose of this preparation was to determine the optimal calcium/magnesium ratio in DSW. Human embryonic kidney (HEK293) cells were exposed to sodium chloride (NaCl) for 2 h to induce release of reactive oxygen species (ROS). Thereafter, the cells were treated with the respective DSW samples before ROS concentrations, as well as antioxidant enzyme activity and protein levels, were measured. Among the water samples, HMLS showed the most protective effect against ROS, whereas the intracellular glutathione content was highest in cells from the HMLS- and HMHC-treated groups. However, TM- and HMHC-treated cells showed similar tendencies to the control group, in terms of mRNA expression of antioxidant genes. These results suggested that DSW may aid in preventing renal oxidative stress caused by excessive sodium intake. Furthermore, it was determined that HMLS and HMHC water samples displayed good antioxidant effects in the kidney cell model, based on the combined results of ROS concentration and antioxidant marker measurements.

• The Korea Journal of Herbology
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• v.33 no.5
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• pp.81-88
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• 2018

Objectives : The aim of this study was to investigate the protective effects of an aqueous extract from Taxillus chinensis (DC.) Danser (TCE) in Monosodium iodoacetate (MIA)-induced osteoarthritis (OA) rat model. Methods : Sprague Dawley male rats were divided into the following four groups (n=6 per group): Normal (saline control), MIA (MIA-induced OA with vehicle), TCE (MIA-induced with TCE treatment), and IM (MIA-induced with indomethacin treatment). Rats in which OA was induced by MIA were treated with TCE (200 mg/kg) or indomethacin (1 mg/kg) for 4 weeks. Weight-bearing on the hind legs and body weights were measured weekly. At the end of the experiment (3 weeks after MIA injection), serum aspartate aminotransferase and alanine aminotransferase levels were measured to assess the liver toxicity induced by TCE. Its effects on serum inflammatory cytokine levels and tissue histopathology were also evaluated. Results : TCE restored the hind limb weight-bearing distribution. Serum levels of Interleukin 6 (IL-6), Tumor necrosis factor alpha (TNF-${\alpha}$) and Leukotriene B4 (LTB4) were significantly higher in the MIA group than in the Normal group, but serum IL-6 levels were significantly lower in the TCE group. In the TCE group, the synovial membrane was protected in hematoxylin and eosin and Safranin-O staining, respectively. Conclusions : TCE recovered the hind paw weight bearing distribution, inhibited the production of inflammatory cytokine, and protected synovial tissue and cartilage in the OA rat model. Therefore, TCE appears to be an effective therapeutic agent for treating OA and OA-related symptoms.

• Asia Marketing Journal
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• v.14 no.1
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• pp.1-24
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• 2012

Nowadays, customer satisfaction has been one of company's major objectives, and the index to measure and communicate customer satisfaction has been generally accepted among business practices. The major issues of CSI(customer satisfaction index) are three questions, as follows: (a)what level of customer satisfaction is tolerable, (b)whether customer satisfaction and company performance has positive causality, and (c)what to do to improve customer satisfaction. Among these, the second issue is recently attracting academic research in several perspectives. On this study, the second issue will be addressed. Many researchers including Anderson have regarded customer satisfaction as core competencies, such as brand equity, customer equity. They want to verify following causality "customer satisfaction → market performance(market share, sales growth rate) → financial performance(operating margin, profitability) → corporate value performance(stock price, credit ratings)" based on the process model of marketing performance. On the other hand, Insoo Jeon and Aeju Jeong(2009) verified sequential causality based on the process model by the domestic data. According to the rejection of several hypotheses, they suggested the balance model of marketing performance as an alternative. The objective of this study, based on the existing process model, is to examine the causal relationship between customer satisfaction and corporate value performance. Anderson and Mansi(2009) proved the relationship between ACSI(American Customer Satisfaction Index) and credit ratings using 2,574 samples from 1994 to 2004 on the assumption that credit rating could be an indicator of a corporate value performance. The similar study(Sangwoon Yoon, 2010) was processed in Korean data, but it didn't confirm the relationship between KCSI(Korean CSI) and credit ratings, unlike the results of Anderson and Mansi(2009). The summary of these studies is in the Table 1. Two studies analyzing the relationship between customer satisfaction and credit ratings weren't consistent results. So, in this study we are to test the conflicting results of the relationship between customer satisfaction and credit ratings based on the research model considering Korean credit ratings. To prove the hypothesis, we suggest the research model as follows. Two important features of this model are the inclusion of important variables in the existing Korean credit rating system and government support. To control their influences on credit ratings, we included three important variables of Korean credit rating system and government support, in case of financial institutions including banks. ROA, ER, TA, these three variables are chosen among various kinds of financial indicators since they are the most frequent variables in many previous studies. The results of the research model are relatively favorable : R², F-value and p-value is .631, 233.15 and .000 respectively. Thus, the explanatory power of the research model as a whole is good and the model is statistically significant. The research model has good explanatory power, the regression coefficients of the KCSI is .096 as positive(+) and t-value and p-value is 2.220 and .0135 respectively. As a results, we can say the hypothesis is supported. Meanwhile, all other explanatory variables including ROA, ER, log(TA), GS_DV are identified as significant and each variables has a positive(+) relationship with CRS. In particular, the t-value of log(TA) is 23.557 and log(TA) as an explanatory variables of the corporate credit ratings shows very high level of statistical significance. Considering interrelationship between financial indicators such as ROA, ER which include total asset in their formula, we can expect multicollinearity problem. But indicators like VIF and tolerance limits that shows whether multicollinearity exists or not, say that there is no statistically significant multicollinearity in all the explanatory variables. KCSI, the main subject of this study, is a statistically significant level even though the standardized regression coefficients and t-value of KCSI is .055 and 2.220 respectively and a relatively low level among explanatory variables. Considering that we chose other explanatory variables based on the level of explanatory power out of many indicators in the previous studies, KCSI is validated as one of the most significant explanatory variables for credit rating score. And this result can provide new insights on the determinants of credit ratings. However, KCSI has relatively lower impact than main financial indicators like log(TA), ER. Therefore, KCSI is one of the determinants of credit ratings, but don't have an exceedingly significant influence. In addition, this study found that customer satisfaction had more meaningful impact on corporations of small asset size than those of big asset size, and on service companies than manufacturers. The findings of this study is consistent with Anderson and Mansi(2009), but different from Sangwoon Yoon(2010). Although research model of this study is a bit different from Anderson and Mansi(2009), we can conclude that customer satisfaction has a significant influence on company's credit ratings either Korea or the United State. In addition, this paper found that customer satisfaction had more meaningful impact on corporations of small asset size than those of big asset size and on service companies than manufacturers. Until now there are a few of researches about the relationship between customer satisfaction and various business performance, some of which were supported, some weren't. The contribution of this study is that credit rating is applied as a corporate value performance in addition to stock price. It is somewhat important, because credit ratings determine the cost of debt. But so far it doesn't get attention of marketing researches. Based on this study, we can say that customer satisfaction is partially related to all indicators of corporate business performances. Practical meanings for customer satisfaction department are that it needs to actively invest in the customer satisfaction, because active investment also contributes to higher credit ratings and other business performances. A suggestion for credit evaluators is that they need to design new credit rating model which reflect qualitative customer satisfaction as well as existing variables like ROA, ER, TA.

• Tuberculosis and Respiratory Diseases
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• v.48 no.4
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• pp.478-486
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• 2000

Background : In acute lung injury, alveolar macrophages play a pivotal role in the inflammatory process during the initiation phase and in the reconstruction and fibrosis process during the later phase. Recently, it has been proven that alveolar macrophages are constituted by morphologically, biochemically and immunologically heterogenous cell subpopulations. The possibility of alterations to these characteristics of the alveolar macrophage population during lung disease has been raised. To investigate such a possibility a hyperoxic rat lung model was made to check the distributional and morphological changes of rat alveolar macrophage subpopulation in acute hyperoxic lung injury. Method : Alveolar macrophage were lavaged from normal and hyperoxic lung injury rats and separated by discontinuous gradients of percoll. After cell counts of each density fraction were accessed, the morphomeric analysis of alveolar macrophages was performed on cytocentrifuged preparations by transmission electron micrograph. Result : 1. The total alveolar macrophage cell count significantly increased up to 24 hours after hyperoxic challenge (normal control group $171.6{\pm}24.1{\times}10^5$, 12 hour group $194.8{\pm}17.9{\times}10^5$, 24 hour group $207.6{\pm}27.1{\times}10^5$, p<0.05). oHoHH However the 48 hour group ($200.0{\pm}77.8{\times}10^5$) did not show a significant difference. 2. Alveolar septal thickness significantly increased up to 24 hours after hyperoxic challenge(normal control group $0.7{\pm}0.2{\mu}m$, 12 hour group $1.5{\pm}0.4{\mu}m$, 24 hour group $2.3{\pm}0.4{\mu}m$, p<0.05). However the 48 hour group did not show further change ($2.5{\pm}0.4{\mu}m$). Number of interstitial macrophage markedly increased at 24 hour group. 3. Hypodense fraction(fraction 1 and fraction 2) of alveolar macrophage showed a significant increase following hyperoxic challenge ($\beta=0.379$.$\beta=0.694$. p<0.05) ; however, fraction 3 was rather decreased following the hyperoxic challenge($\beta=0.815$. p<0.05), and fraction 4 showed an irregular pattern. 4. Electron microscopic observation of alveolar macrophage from each fraction revealed considerable morphologic heterogeneity. Cells of the most dense subfraction(fraction 4) were small, round, and typically highly ruffled with small membrane pseudopods. Cells of the least dense fraction (fraction 1) were large and showed irregular eccentric nucleus and high number of heterogenous inclusions. Conclusion : In conclusion, these results suggest that specific hypodense alveolar macrophage subpopulation may play a an important role in an acute hyperoxic lung injury model But further study, including biochemical and immunological function of these subpopulations, is needed.

• Tuberculosis and Respiratory Diseases
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• v.47 no.2
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• pp.161-171
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• 1999

Background: Interleukin-12 (IL-12) can induce antitumor effects in vivo. This antitumor effect is associated with T cell infiltration but the effect of IL-12 on the steps of T cell migration into the tumor tissue has not been fully elucidated. This study focused on the effect of IL-12 on the tumor growth and the metastasis and on the expression of E-selectin, an adhesion molecule which is activated endothelial specific in its expression. In addition, we studied whether the expression of E-selectin is associated with the TNF-$\alpha$, a cytokine that its production is increased by IL-12 and has functions inducing a variety of adhesion molecules. Methods: Mice of C57BL/6 strain were injected with Lewis lung cancer cells followed by either IL-12, TNF-$\alpha$, or normal saline by intraperitoneal route. Twenty eight days after tumor cell inoculation, metastatic nodules of lung were enumerated and immunohistochemical staining of the subcutaneous tumors were performed with monoclonal antibodies to CD4, CD8, CD16, and E-selectin. In IL-12 treated mice, the subcutaneously implanted Lewis lung tumors were decreased in size and the metastases were also decreased in number compared to control mice. On tumor tissues, increased infiltration of CD4+, CD8+, and CD16+ cells were oberved in IL-12 treated mice compared to control mice. In control mice, E-selectin was absent on tumor vessels, but the expression of E-selectin was increased on tumor vessels of IL-12 treated mice. Administration of TNF-$\alpha$ increased not only the expression of E-selectin but also infiltrations of CD4+, CD8+, and CD16+ cells on tumor tissues. Conclusions: These results demonstrate that IL-12 inhibits tumor growth and metastases through infiltrations of inflammatory cells in mouse model of Lewis lung carcinoma and E-selectin may playa role in inflammatory cell recruitment on tumor tissue following IL-12 administration. Also, TNF-$\alpha$ may have a role as a mediator responsible for the IL-12 induced expression of E-selectin.