• Corrosion Science and Technology
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• v.16 no.2
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• pp.49-58
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• 2017

Many research efforts on the effect of nitrogen on the corrosion resistance of stainless steels have been reported, but little research has been conducted on the effect of nitrogen for the weldment of stainless steels by the seal-weld method. Therefore, this work focused on the determining the corrosion resistance of tube/tube sheet mock-up specimen for sea water condensers, and elucidating the effect of shielding nitrogen gas on its resistance. The pitting corrosion of autogenously welded specimen propagated preferentially along the dendritic structure. Regardless of the percent of shielding nitrogen gas, the analyzed nitrogen contents were very much lower than that of the bulk specimen. This can be arisen because the nitrogen in shielding gas may partly dissolve into the weldment, but simultaneously during the welding process, nitrogen in the alloy may escape into the atmosphere. However, the pitting resistance equivalent number (PREN) of the interdendrite area was higher than that of the dendrite arm, regardless of the shielding gas percent; and the PREN of the interdendrite area was higher than that of the base metal; the PREN of the dendrite arm was lower than that of the base metal because of the formation of (Cr, Mo) rich phases by welding.

• Journal of the Korean earth science society
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• v.25 no.6
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• pp.428-442
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• 2004

Dustfall samples were collected by the modified American dust jar (bulk type) at 5 sampling sites in the Nakdong river area from lune 2002 to May 2003. Nineteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Si, V, Zn, $Cl^-$, $NO_3^-$, $SO_4^{2-}$, and $NH_4^+$) were analyzed via the combination of ICP/AES, AAS, IC and UV. The purposes of this study were to qualitatively evaluate the chemical composition of dustfalls by examining their regional and seasonal distribution patterns. Computation of the enrichment factor showed that well-defined anthropogenic sources, particularly in Pb were found in the order Gamjeondong (industrial area), Wondong, Silla University, Samrangiin and Mulgum. The seasonal mean of soil contribution showed its highest value (16.3%) during the winter with an annual mean of 11.2%. The concentration ratio of [$SO_4^{2-}/NO_3^-$] was found to be highest (5.12) during the winter, while the lowest ratio value (3.30) was seen during the all. fall, Also regional equivalent ratios of [$SO_4^{2-}/NO_3^-$] were found in the order: Silla University (6.78), Gamjeondong (4.98), Mulgum (3.95), Wondong (3.85), and Samrangjin (2.87). Seasonal distribution of water soluble components for total dustfall were found in the order: spring (71.6%), summer (61.2%), fall (49.2%) and winter (48.6%) with a mean ratio of 57.6%. Regional contribution of sea salts of water soluble ions were found in the order: Silla university (34.5%), Gamjeondong (28.3%), Wondong (17.3%), Samrangiin (17.2%) and Mulgum (13.8%), the total mean contribution rate was 22.1%. As for the chemical composition of dustftll on the lower Nakdong river, there is a decreased influence of sea salt and artificial anthropogenic sources and increased influence of soil particle inland. Also, the total amount of deposition on the lower Nakdong river has decreased, with the river's surface serving as a confounding factor in resuspending dusts.

• Journal of Preventive Medicine and Public Health
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• v.6 no.1
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• pp.27-41
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• 1973

In order to provide some basic data for the control of air and water pollution in Korea, the authors have estimated the amount of air and water pollutants emitted from industries which are employed over 20 employees. This study have done from July 1, 1972 to the end of March 1973. The results are as followings; 1. Total number of establishments with over 20 employees is 5,197 in Korea and the largest group establishments was the manufacturing of textiles with 1,363 establishments (26.2%). 2. By order of number of employees it was observed that there 2,800 industries with 20-59(53.9%) employees, 1,101 with 50-99 (21.2%), 571 with 100-199 (11.0%), 501 with 200-499 (9.6%) and 225 with over 500 (4.3%) respectively. 3. By order of regional distribution, it was observed that there were 2,257 industries in Seoul (43.2%) and 736 industries in Pusan(14.2%). 4. Industrial coal consumption was 596,154 M/T in 1972, but it' 11 be 315,000 M/T in 1980. Fuel consumption was 4,972,000 K1 in 1972, and estimated volume will be 19,370,000 K1 in 1980. 5. Total amounts of air polutants entitled from industries by fuel combustion were sulfur oxides 79,459 tons, carbon monoxide 33,908 tons, particulate 31,304 tons and hydrocarbon 30,280 tons in 1972 but in 1990 there will be sulfur oxides 1,010,474 tons, nitrogen oxides 204,575 tons, carbon monoxide 68,014 tons, particulate 64,820 tons and hydrocarbon 67,622 tons, respectively. 6. Annual emitted air pollutants through the working processes were sulfur oxides 91,250 tons and nitrogen oxides 32,485 tons in 1972, but sulfur oxides 118,625 tons and nitrogen oxides 42,555 tons will be present in 1980, respectively. 7. Annual emitted air pollutants by national unit area amounted to $0.77ton/km^2/year$ in 1965 and $14.7ton/km^2/year$ in 1980. 8. Total industrial wastes from all industries in Korea were estimated at 810,360 tons/day in 1972; manufacturing of chemicals and plastic products showed the highest amount of wastes at 470,000 tons/day. 9. The amounts of water pollutants due to industrial wastes were the B.O.D., 471.5 tons/day, suspended solid 331.5 tons/day, CN, 2.3 tons/day, and Cr. 3.4 tons/day in 1972, but it might be evident of a B.O.D. of 3,388 tons/day, suspended solid 2,544 tons/day, CN 20.1 tons/day, and 26.5 tone/day in 1990. 10. Total population equivalent of B.O.D. was 943,000 in 1972, and the estimated value in 1950 will be 6,780,000.

• Journal of Environmental Health Sciences
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• v.45 no.6
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• pp.577-582
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• 2019

Objectives: The purpose of this survey was to assess the concentrations of heavy metals in the atmosphere of Pocheon City by measuring heavy metals in the industrial complex area and at the city air measuring station, and also to assess the degree of impact that the industrial area has on urban air quality. Methods: Sampling was carried out between February 2018 and November 2018 at two sites in the industrial complex and in the city air monitoring stations. Results: At the industrial complex in Pocheon City, air pollutant emitting businesses were emitting concentrations of fine dust (PM₁₀) between 45 and 60 ㎍/㎥ higher than in the city air. The daily maximum concentrations of lead (Pb), manganese (Mn), and cadmium (Cd) in the industrial complex are below the WHO recommendation standard (annual average), and the impact on the urban atmosphere is judged to be insignificant. Three to five percent of fine dust (PM₁₀) consists of metallic materials, and as the fine dust increased, metals were detected proportionally. Although cadmium (Cd) and beryllium (Be) were not detected in the city air in Pocheon and chromium (Cr), copper (Cu), and arsenic (As) were found to be 50 percent or less, it is deemed that copper (Cu) was detected at unusually high levels due to unknown air pollutants, which requires regular heavy metal measurement and cause verification. Conclusions: An analysis of the heavy metals in the industrial zone and the urban atmosphere in Pocheon City in this study showed that the linear relationship of heavy metals in the industrial zone, or the direct impact relationship, on the heavy metals in the urban atmosphere could not be estimated. The sampling device for equivalent assessment of particulate matter installed at air pollution monitoring stations is highly likely to be used for analysis of fine dust and heavy metals.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.2
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• pp.62-67
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• 2014

A glomerular filtration rate (GFR) study is a test that uses radioactive materials or tracers (radiopharmaceuticals) and a computer to see how well the kidneys are working. Asan Medical Center analyzed and compared data between kidney depth, acquired from kidney donors' CT image and acquired from Gates method's GFR value that are calculated by Tonnesen equation. This study was able to confirm that kidney depth measured from CT image was higher than the Gates Method's GFR value, which was calculated by Tonnessen equation; the direct relationship among pathologic results is confirmed. Particularly, kidney donor whose kidney was at the pelvic area had direct relationship with other clinical results. During the GFR test, it is necessary to confirm the location of kidney has no change with reference of CT image. If kidney depth is manually corrected using CT image when we measures GFR of deformed or horse-shoe kidney, it would be possible to acquire the compatible value which is equivalent to clinical result. There would be a possible issue of appropriateness that whether the applied GFR using CT image's kidney depth has clinical validity. In case of a pediatric patient, the GFR derived from Tonnesen was quiet underestimated while manual method and Gordon stay in normal range. Which results may be correct among them? There have been many reports about kidney depth, to be an accurate index of GFR in children. As one of the study performers, we should contemplate what the best option for pediatric patients would be.

• Clinical and Experimental Pediatrics
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• v.48 no.11
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• pp.1187-1192
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• 2005

Purpose : The purpose of this study is to determine the effectiveness of intravenous immunoglobuin (IVIG) administration in fullterm neonates having clinically suspected neonatal sepsis. Methods : Forty full-term neonates admitted to the neonatal intensive care unit with clinically suspected neonatal sepsis, who had at least two positive diagnostic criteria were enrolled. Twenty neonates were enrolled into the IVIG arm and 20 in the placebo arm. Neonates with a gestational age of less than 36 weeks and those with any major congenital malformation were excluded. The neonates were randomized to receive 1 g/kg of IVIG or equivalent amount of normal saline. The treatments including antibiotics and supportive care were administered. Results : The neonates in the therapy and placebo groups were comparable in terms of birth weight, gestational age, sex distribution, duration of antibiotics therapy and admission, elevation of serum IgG level, mortality rate, change of CBC, and serum level of acute phase reactants etc. Conclusion : Serum IgG values increased significantly 5 days after administration of IVIG in the IVIG-treated group and decreased significantly 5 days after administration of normal saline in the placebo group. However, there was no significant difference in the duration of antibiotics therapy and admission, or of mortality between the IVIG-treated and placebo groups. No adverse reactions to the IVIG infusions were noted during the study. Our preliminary observations suggest that the administration of 1 g/kg IVIG to neonates had some effect on augmentation of humural immune status in neonates with clinically suspected sepsis. But further study is needed to verify the benefit of IVIG infusion to neonatal sepsis.

• Journal of Distribution Research
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• v.17 no.2
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• pp.63-92
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• 2012

This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective responses. Information relevancy was integrated into pleasure-arousal-dominance (PAD) emotional state model in the present study as a conceptual framework. The results of an online survey of 335 mobile phone users in the U.S. indicated the positive effects of arousal and information relevancy on pleasure. In addition, there was a significant relationship between pleasure and intention to use a LBMSS. However, the relationship between dominance and pleasure was not statistically significant. The results of the present study provides insight to retailers and marketers as to what factors they need to consider to implement location-based mobile shopping services to improve their business performance. Extended Abstract : Location aware technology has expanded the marketer's reach by reducing space and time between a consumer's receipt of advertising and purchase, offering real-time information and coupons to consumers in purchasing situations (Dickenger and Kleijnen, 2008; Malhotra and Malhotra, 2009). LBMSS increases the relevancy of SMS marketing by linking advertisements to a user's location (Bamba and Barnes, 2007; Malhotra and Malhotra, 2009). This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective response. The purpose of the study was to examine the relationship among information relevancy and affective variables and their effects on intention to use LBMSS. Thus, information relevancy was integrated into pleasure-arousal-dominance (PAD) model and generated the following hypotheses. Hypothesis 1. There will be a positive influence of arousal concerning LBMSS on pleasure in regard to LBMSS. Hypothesis 2. There will be a positive influence of dominance in LBMSS on pleasure in regard to LBMSS. Hypothesis 3. There will be a positive influence of information relevancy on pleasure in regard to LBMSS. Hypothesis 4. There will be a positive influence of pleasure about LBMSS on intention to use LBMSS. E-mail invitations were sent out to a randomly selected sample of three thousand consumers who are older than 18 years old and mobile phone owners, acquired from an independent marketing research company. An online survey technique was employed utilizing Dillman's (2000) online survey method and follow-ups. A total of 335 valid responses were used for the data analysis in the present study. Before the respondents answer any of the questions, they were told to read a document describing LBMSS. The document included definitions and examples of LBMSS provided by various service providers. After that, they were exposed to a scenario describing the participant as taking a saturday shopping trip to a mall and then receiving a short message from the mall. The short message included new product information and coupons for same day use at participating stores. They then completed a questionnaire containing various questions. To assess arousal, dominance, and pleasure, we adapted and modified scales used in the previous studies in the context of location-based mobile shopping service, each of the five items from Mehrabian and Russell (1974). A total of 15 items were measured on a seven-point bipolar scale. To measure information relevancy, four items were borrowed from Mason et al. (1995). Intention to use LBMSS was captured using two items developed by Blackwell, and Miniard (1995) and one items developed by the authors. Data analyses were conducted using SPSS 19.0 and LISREL 8.72. A total of usable 335 data were obtained after deleting the incomplete responses, which results in a response rate of 11.20%. A little over half of the respondents were male (53.9%) and approximately 60% of respondents were married (57.4%). The mean age of the sample was 29.44 years with a range from 19 to 60 years. In terms of the ethnicity there were European Americans (54.5%), Hispanic American (5.3%), African-American (3.6%), and Asian American (2.9%), respectively. The respondents were highly educated; close to 62.5% of participants in the study reported holding a college degree or its equivalent and 14.5% of the participants had graduate degree. The sample represents all income categories: less than $24,999 (10.8%), $25,000-$49,999 (28.34%), $50,000-$74,999 (13.8%), and $75,000 or more (10.23%). The respondents of the study indicated that they were employed in many occupations. Responses came from all 42 states in the U.S. To identify the dimensions of research constructs, Exploratory Factor Analysis (EFA) using a varimax rotation was conducted. As indicated in table 1, these dimensions: arousal, dominance, relevancy, pleasure, and intention to use, suggested by the EFA, explained 82.29% of the total variance with factor loadings ranged from .74 to .89. As a next step, CFA was conducted to validate the dimensions that were identified from the exploratory factor analysis and to further refine the scale. Table 1 exhibits the results of measurement model analysis and revealed a chi-square of 202.13 with degree-of-freedom of 89 (p =.002), GFI of .93, AGFI = .89, CFI of .99, NFI of .98, which indicates of the evidence of a good model fit to the data (Bagozzi and Yi, 1998; Hair et al., 1998). As table 1 shows, reliability was estimated with Cronbach's alpha and composite reliability (CR) for all multi-item scales. All the values met evidence of satisfactory reliability in multi-item measure for alpha (>.91) and CR (>.80). In addition, we tested the convergent validity of the measure using average variance extracted (AVE) by following recommendations from Fornell and Larcker (1981). The AVE values for the model constructs ranged from .74 through .85, which are higher than the threshold suggested by Fornell and Larcker (1981). To examine discriminant validity of the measure, we again followed the recommendations from Fornell and Larcker (1981). The shared variances between constructs were smaller than the AVE of the research constructs and confirm discriminant validity of the measure. The causal model testing was conducted using LISREL 8.72 with a maximum-likelihood estimation method. Table 2 shows the results of the hypotheses testing. The results for the conceptual model revealed good overall fit for the proposed model. Chi-square was 342.00 (df = 92, p =.000), NFI was .97, NNFI was .97, GFI was .89, AGFI was .83, and RMSEA was .08. All paths in the proposed model received significant statistical support except H2. The paths from arousal to pleasure (H1: ${\ss}$=.70; t = 11.44), from information relevancy to intention to use (H3 ${\ss}$ =.12; t = 2.36), from information relevancy to pleasure (H4 ${\ss}$ =.15; t = 2.86), and pleasure to intention to use (H5: ${\ss}$=.54; t = 9.05) were significant. However, the path from dominance to pleasure was not supported. This study investigated consumer intention to use a location-based mobile shopping service (LBMSS) that integrates cognitive and affective responses. Information relevancy was integrated into pleasure-arousal-dominance (PAD) emotional state model as a conceptual framework. The results of the present study support previous studies indicating that emotional responses as well as cognitive responses have a strong impact on accepting new technology. The findings of this study suggest potential marketing strategies to mobile service developers and retailers who are considering the implementation of LBMSS. It would be rewarding to develop location-based mobile services that integrate information relevancy and which cause positive emotional responses.