• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.21 no.7
• /
• pp.675-684
• /
• 2020

To prevent safety accidents caused by aging pipe infrastructure and to maintain water quality, construction projects for water and sewage pipes are actively conducted across Korea. This study analyzed the criteria situations, site survey details, and regulation revisions related to the calculation of construction cost standards for pipe laying and joining work. The analysis showed that the major causes for revision are the unclear construction scope, limitations in implementing some pipe materials due to installation facility types, workforce focused on ordinary labor, limitations of manual laying work, and the lack of tool hire cost and machine expense-calculation criteria. Field studies were conducted to categorize the pipes according to their features, in addition to identifying the use of lifting heavy equipment and light equipment. In addition, excavation and testing work conducted in connection to pipe laying, as well as the use of skilled labor, were investigated. The current study clarified the work scope through new common items, provides an organization based on the pipe material, adjusted the workforce ratio to focus more on skilled labor, and developed grounds for calculating machine expenses. These revisions were estimated to save approximately 1.28% of the construction costs in each project according to an analysis of the construction cost impact study. truction costs in each project, according to an analysis of construction cost impact study.

• Journal of Korean Society of Environmental Engineers
• /
• v.32 no.6
• /
• pp.563-580
• /
• 2010

In 2009 the Korea Ministry of Environment announced 'A Comprehensive Plan for the Improvement of Sewer Service in Rural Area' aiming at reduction of the sewer service gap between urban and rural areas as well as improvement in the residential environment of the rural area. According to the plan, the sewer system supply rate for the rural area is expected to reach up to 75% until 2015 with the budget of 4.7 trillion won (Korean currency). It is not certain, however, that the increase in the sewer system supply rate will accompany improvement of water quality in receiving water because several veiled problems that can occur in small-scale sewer treatment plants are poorly addressed in the plan. In this study, those issues for the small-scale sewer treatment plants and their solutions were discussed based on a case study in which we investigated 19 treatment facilities at two rural regions in Gyeonggi province. This study also included strategies useful for the plan. From the results of investigation, some problems, e.g., high hourly variations but low in flowrates and low mass loading were commonly identified. Although operation parameters in sewer treatment plants require to be modified depending on the mass loading, most of the plants were operated with the initial design parameters which causes the decrease of removal efficiency. In the intensive diagnosis, we arranged and applied solutions (e.g., flow equalization, air on/off time control, etc) to the two selected plants and found out improvement of effluent water quality, especially organic matters (COD and SS) and T-N with better denitrification performance.

• Survey Research
• /
• v.10 no.3
• /
• pp.85-106
• /
• 2009

This study is an attempt to provide some answers to question about how characteristics and general recognition regarding internet use in Korea and Japan influence fostering and maintaining on-line social network in each of countries. Survey is used to compare Korean internet users and Japanese internet users in terms of characteristics of on-line social network, individual's propensity for internet use, including their recognition on internet. The study's main findings go as follows. First, Korean internet users tend to be more active in using internet than Japanese internet users do, thus having larger on-line social network and more intensive internet use than Japanese internet users do. However, there is a commonality that majority of internet users in both countries use internet to connect them to person with whom they have private relationship but they cannot meet frequently. Second, for Korean internet users, individual's propensity, characteristics, and recognition regarding internet use is not related to how to contact others. To the contrary, for Japanese internet users, how to contact others in on-line setting seems to vary according to whether or not they have relation-oriented internet use and how they recognize the availability of internet. Third, a commonality regarding the size of on-line social network is found between Korea and Japan that the total numbers of people enrolled as network increases if people use internet in order to get information. This confirms previous finding that relationship based on weak tie is instrumental in fostering on-line social relations and likely produces advantage in getting information. Finally, for Japanese internet users, the degree of risk recognized in on-line setting, that is the degree of interpersonal trust, appears to greatly influence overall relationship -building in on-line.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.37 no.1
• /
• pp.175-185
• /
• 2017

As the gas is manufactured, handled and used more often due to the continuous increase of gas, the related facility gets expanded and more complex causing small and big accident which causes economic loss including damage for humans and materials. The gas pipeline, the most common gas facility, has the biggest risk of accidents. Especially in the urban area and densely populated areas, the accident due to the high pressure pipeline may cause even more serious damages. To prevent the accident caused by the buried pipeline, it is required for the relevant authorities to evaluate the damage and risk of the whole pipeline system effectively. A risk is usually defined as a possibility or probability of an undesired event happening, and there is always a risk even when the probability of failure is set low once the pipeline is installed or under operation. It is reported that the accident caused by the failure of the pipeline rarely happens, however, it is important to minimize the rate of accidents by analyzing the reason of failure as it could cause a huge damage of humans and property. Therefore, the paper rated the risk of pipelines with quantitative numbers using the qualitative risk analysis method of the Scoring Model. It is assumed that the result could be effectively used for practical maintenance and management of pipelines securing the safety of the pipes.

• Korean Chemical Engineering Research
• /
• v.51 no.3
• /
• pp.335-341
• /
• 2013

Ammonia circulation reactor (ACR) was devised for the effective pretreatment of corn stover. This method is designed to circulate aqueous ammonia continuously so that it can reduce the chemical and water consumption during pretreatment. In this study, ammonia pretreatment with various reaction conditions such as reaction time (4~12 hour), temperature ($60{\sim}80^{\circ}C$), and solid:liquid ratio (1:3~1:8) was tested. Chemical compositions including solid remaining after reaction, lignin and carbohydrates were analyzed and enzymatic digestibility was also measured. It was observed that as reaction conditions become more severe, lignin removal was significantly affected, which was in the range of 47.6~70.6%. On the other hands, glucan and xylan losses were not substantial as compared to that of lignin. At all tested conditions, the glucan loss was not changed substantially, which was between 4.7% and 15.2%, while the xylan loss varied, which was between 7.4% and 25.8%. With (15 FPU-GC220+30 CBU)/g-glucan of enzyme loading, corn stover treated using ammonia circulation reactor for 8~12 hours resulted in 90.1~94.5% of 72-h glucan digestibility, which was higher than 92.7% of $Avicel^{(R)}$-101. In addition, initial hydrolysis rate (at 24 hour) of this treated corn stover was 73.0~79.4%, which was shown to be much faster than 69.5% of $Avicel^{(R)}$-101. As reaction time increased, more lignin removal and it was assumed that the enhanced enzymatic digestibility of treated biomass was attributed to the lignin removal.

• Food Science and Preservation
• /
• v.19 no.6
• /
• pp.893-900
• /
• 2012

To establish a new manufacturing process of low-salted fermented anchovy sauce, commercial fermented anchovy sauce with 23% NaCl was desalted using a spirit. The proximate composition, total nitrogen, amino nitrogen, Escherichia coli, and total and free amino acid contents were analyzed to evaluate the quality characteristics of commercial salted fermented anchovy sauce (CFAS) and low-salt fermented anchovy sauce by desalting processing (LFAS). The salinity of saltwater and fermented anchovy sauce decreased with an increase in the spirit added to 23% NaCl saltwater and 23% NaCl commercial fermented anchovy sauce. The total nitrogen and amino nitrogen contents were higher in LFAS than in CFAS. The major amino acids that were commonly found in CFAS and LFAS were glutamic acid, alanine, lysine and leucine. Basic data were provided for commodification research on low-salt fermented anchovy sauce, which is very important for the diet of humans.

• Journal of International Area Studies (JIAS)
• /
• v.13 no.1
• /
• pp.135-156
• /
• 2009

The two waves of EU enlargement in 2004 and 2007, have been milestones of European integration. While research has been conducted into the impact of these events on both the European and the global economies,1 there have been few attempts to assess the effects of EU enlargement and the introduction of the euro on countries such as Russia, which neighbour the EU but currently have no perspective of accession. This paper aims to provide an assessment of the effects that EU enlargement and the introduction of the euro have had on Russia, the largest country neighbouring the EU. In particular, it focuses on trade and investment links between the EU and Russia, as well as the use of the energy by Russian residents and authorities. Economic links between Russia and the EU are found to have strengthened considerably in the areas of trade, investment and other financial flows in recent years. Strong growth, particularly in Russia, as well as the high price of oil and gas, Russia's major export items, has facilitated this expansion of trade and finance. Moreover, available data do not suggest that EU enlargement has had a negative impact on Russia in terms of trade or investment diversion. Thus, the strategic partnership between Russia and the EU has been increasingly underpinned by an expansion of cross-border economic activities. Thus, the paper contributes to two broad strands of literature on this subject, namely the impact of regional trade and economic arrangements on non-member countries and the international role of currencies.

• Journal of Animal Science and Technology
• /
• v.53 no.5
• /
• pp.419-428
• /
• 2011

This study was conducted to test the efficacy of Ulva pertusa kjellman as immunomodulators under lipopolysaccharide (LPS) challenge in broilers by investigating their effects on serum superoxide dismutase (SOD) like ability, immunoglobulin concentration, and splenic cytokine mRNA expression. A total of ninety six1-d-old male broiler chicks (Ross 308) were divided into 4 treatment groups with 8 replicates of 3 birds in each group. NC (negative control, no immune substances), PC (positive control, ${\beta}$-glucan 25 ppm), Ulva P (Ulva pertusa kjellman Powder 3%), and Ulva E (Extract form Ulva pertusa kjellman 0.3%) were added in feed with respective substance. Heparinized venous blood and spleens were collected from five birds per dietary treatment at 5 wk of age. The SOD like activities in Ulva P and Ulva E were significantly increased in comparison with other groups (P<0.05). The immunoglobulin M content was lower in the Ulva E than other groups (P<0.05). Expression patterns of splenic cytokine mRNA in the IL-$1{\beeta}$, IL-2 and IL-6 were similar. Expression rate of IL-$1{\beta}$, IL-2 and IL-6 in Ulva pertusa kjellman (Ulva P, Ulva E) were decreased (P<0.05) in comparison to other groups. Expression rate of IL-$1{\beta}$, IL-2 and IL-6 were significantly lower in groups treated with Ulva E than Ulva P. In conclusion, dietary supplementation of Ulva pertusa kjellman improved SOD like activity and affect immune system by inhibiting inflammatory response in broiler chicks. In addition, it is more effective to use Ulva pertusa kjellman extract than powder for immunomodulatory function. These results suggest the possibility that Ulva pertusa kjellman could be used as the immunomodulator for inflammatory response in broiler chicks.

• Asian Journal of Turfgrass Science
• /
• v.19 no.1
• /
• pp.27-38
• /
• 2005

This study was conducted to find out withering and dying trends of turfgrasses on the base of tree, and to investigated how much area of turfgrasses withering and dying were progressed on angle of inclination at golf course. Turfgrasses withering and dying on base of trees on slope was extended more to the down-solpe direction than to the up-solpe direction. This trend was common in all experiment plot. Turfgrasses on the base of trees were withered and dead by competing with tree root fur nutrients and moisture in soil. But the trend of the withering and dying in some experiment plots occurred by soil erosion following turfgrass withering and dying occurring on upside ridge. This trend was generally appeared in region of tree community at upside ridge. The form of turfgrass withering and dying on the base of tree in some experiment plots was similar to that of the tree crown. This withering and dying from occurred at the $11^{th}$ experiment plot in Ji San Golf Course and the $6^{th}$ experiment plot in East valley Golf Course.

• Journal of Nutrition and Health
• /
• v.43 no.2
• /
• pp.189-196
• /
• 2010

Malnutrition has been associated with higher hospital costs, mortality, rates of complications and longer length of hospital stay. Several nutritional screening tools have been developed to identify patients with malnutrition risk. However, many of those require much time and labor to administer and may not be applicable to a Korean population. Therefore, the aim of this study was to develop nutritional screening tool for Korean inpatients. Then we compare nutritional screening tools that developed and previously described. Seven hundred sixty-four patients at hospital admission were screened nutritional status and classified as well nourished, malnutrition stage 1 or stage 2 by the KNNRS (Kyunghee Neo Nutrition Risk Screening), PG-SGA (Patient-Generated Subjective Global Assessment) and NRS-2002 (Nutritional Risk Screening-2002). The KNNRS, PG-SGA and NRS-2002 respectively classified 28.7%, 51.3%, 48.5% of patients as malnourished status. Compared to the PG-SGA, the KNNRS had sensitivity 60.7% (95% CI 54.2-67.0) and specificity 81.2% (95% CI 75.3-85.2). Agreement was fair between KNNRS and PG-SGA (k = 0.34). Compared to the NRS-2002, the KNNRS had sensitivity 57.8% (95% CI 53.4-60.9) and specificity 64.4% (95% CI 60.2-69.8). Agreement was poor between KNNRS and NRS-2002 (k = 0.18). These result should include that the KNNRS and PGSGA have clinical relevance and fair concordance. However the rate of malnourished patients by KNNRS were less than by PG-SGA. For more effectivity of nutritional screening and management, the criteria of KNNRS would be better revised.