• Title/Summary/Keyword: Spring Component

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A Study on the Characteristics of Ion, Carbon, and Elemental Components in PM2.5 at Industrial Complexes in Ansan and Siheung (안산·시흥 산업단지 지역 PM2.5 중 이온, 탄소, 원소성분의 특성 연구)

  • Lee, Hye-Won;Lee, Seung-Hyeon;Jeon, Jeong-In;Lee, Jeong-Il;Lee, Cheol-Min
    • Journal of Environmental Health Sciences
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    • v.48 no.2
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    • pp.66-74
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    • 2022
  • Background: The health effects of particulate matter (PM2.5) bonded with various harmful chemicals differ based on their composition, so investigating and managing their concentrations and composition is vital for long-term management. As industrial complexes emit considerable quantities of pollutants, higher PM2.5 concentrations and chemical component effects are expected than in other places. Objectives: We investigated the concentration distribution ratios of PM2.5 chemical components to provide basic data to inform future major emissions control and PM2.5 reduction measures in industrial complexes. Methods: We monitored five sites near the Ansan and Siheung industrial complexes from August 2020 to July 2021. Samples were collected and analyzed twice per week in spring/winter and once per week in summer/autumn according to the National Institute of Environmental Research in the Ministry of Environments' Air Pollution Monitoring Network Installation and Operation Guidelines. We investigated and compared composition ratios of 29 ions, carbon, and elemental components in PM2.5. Results: The analysis of PM2.5 components at the five sites revealed that ion components accounted for the greatest total mass at approximately 50% while carbon components and elemental components contributed 23~28% and 8~10%, respectively. Among the ionic components, NO3- occupies the greatest proportion. OC occupies the greatest proportion of the carbon components and sulphur occupies the greatest proportion of elemental components. Conclusions: This study investigated the concentration distribution ratios of PM2.5 chemical components in industrial complexes. We believe these results provide basic chemical component concentration ratio data for establishing future air management policies and plans for the Ansan and Siheung industrial complexes.

BEEF MEAT TRACEABILITY. CAN NIRS COULD HELP\ulcorner

  • Cozzolino, D.
    • Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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    • 2001.06a
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    • pp.1246-1246
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    • 2001
  • The quality of meat is highly variable in many properties. This variability originates from both animal production and meat processing. At the pre-slaughter stage, animal factors such as breed, sex, age contribute to this variability. Environmental factors include feeding, rearing, transport and conditions just before slaughter (Hildrum et al., 1995). Meat can be presented in a variety of forms, each offering different opportunities for adulteration and contamination. This has imposed great pressure on the food manufacturing industry to guarantee the safety of meat. Tissue and muscle speciation of flesh foods, as well as speciation of animal derived by-products fed to all classes of domestic animals, are now perhaps the most important uncertainty which the food industry must resolve to allay consumer concern. Recently, there is a demand for rapid and low cost methods of direct quality measurements in both food and food ingredients (including high performance liquid chromatography (HPLC), thin layer chromatography (TLC), enzymatic and inmunological tests (e.g. ELISA test) and physical tests) to establish their authenticity and hence guarantee the quality of products manufactured for consumers (Holland et al., 1998). The use of Near Infrared Reflectance Spectroscopy (NIRS) for the rapid, precise and non-destructive analysis of a wide range of organic materials has been comprehensively documented (Osborne et at., 1993). Most of the established methods have involved the development of NIRS calibrations for the quantitative prediction of composition in meat (Ben-Gera and Norris, 1968; Lanza, 1983; Clark and Short, 1994). This was a rational strategy to pursue during the initial stages of its application, given the type of equipment available, the state of development of the emerging discipline of chemometrics and the overwhelming commercial interest in solving such problems (Downey, 1994). One of the advantages of NIRS technology is not only to assess chemical structures through the analysis of the molecular bonds in the near infrared spectrum, but also to build an optical model characteristic of the sample which behaves like the “finger print” of the sample. This opens the possibility of using spectra to determine complex attributes of organic structures, which are related to molecular chromophores, organoleptic scores and sensory characteristics (Hildrum et al., 1994, 1995; Park et al., 1998). In addition, the application of statistical packages like principal component or discriminant analysis provides the possibility to understand the optical properties of the sample and make a classification without the chemical information. The objectives of this present work were: (1) to examine two methods of sample presentation to the instrument (intact and minced) and (2) to explore the use of principal component analysis (PCA) and Soft Independent Modelling of class Analogy (SIMCA) to classify muscles by quality attributes. Seventy-eight (n: 78) beef muscles (m. longissimus dorsi) from Hereford breed of cattle were used. The samples were scanned in a NIRS monochromator instrument (NIR Systems 6500, Silver Spring, MD, USA) in reflectance mode (log 1/R). Both intact and minced presentation to the instrument were explored. Qualitative analysis of optical information through PCA and SIMCA analysis showed differences in muscles resulting from two different feeding systems.

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Feeding Habits of Small Yellow Croaker, Larimichthys polyactis in Coastal Waters of Korea (한국 연안해역에 출현하는 참조기(Larimichthys polyactis)의 식성)

  • Kang, Da Yeon;Seong, Gi Chang;Kim, Do-Gyun;Jin, Suyeon;Soh, Ho Young;Baeck, Gun Wook
    • Korean Journal of Ichthyology
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    • v.34 no.3
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    • pp.201-207
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    • 2022
  • Total 418 Yellow Croaker Larimichthys polyactis were examined and the range of total length (TL) was 12.0~27.5 cm and average total length was 19.6 cm. The most important prey component in the diets of L. polyactis was Pisces that constituted 46.5% in %IRI (Index of relative importance). Euphausiacea was the second largest prey component. The result of analysis in ontogenetic and seasonal changes significantly exhibited. The proportion of Pisces increased as increasing body size, whereas the consumption of Macrura decreased gradually. The diets also were different among seasons, with the difference particularly being evident between warm (summer and autumn) and cold (winter and spring) seasons. Permutational multivariate analysis of variance (PERMANOVA) revealed significant dietary differences by seasons (P=0.001).

Feeding Habits of the Large Yellow Croaker, Larimichthys crocea in the Coastal Waters of Jeju Island, Korea (한국 제주 연안에 출현하는 부세(Larimichthys crocea)의 식성)

  • Do-Yeon Park;Do-Gyun Kim;Seong-Yong Moon;Jeong-Ho Park;Hee-Yong Kim;Gun Wook Baeck
    • Korean Journal of Ichthyology
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    • v.36 no.2
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    • pp.182-187
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    • 2024
  • Feeding habits of the large yellow croaker, Larimichthys crocea, was studied using 816 specimens collected by large pair-trawl fishery from June 2021 to May 2022 in the coastal waters of Jeju Island, Korea. The range of total length was 19.8~57.4 cm. Using the IRI, Pisces were mainly prey component constituted 57.5%. Euphausiacea and Macrura were important prey component constituted 23.2% and 18.7%, respectively. There was a significant difference in the change in diet composition by size group. As the L. crocea grew, the feeding rate of Euphausiacea decreased and the feeding rate of Pisces increased. There were also significant differences in the changes in diet composition by seasonal group. The most important prey species for L. crocea in the winter and spring were Pisces, in the summer it was Macrura, and in the fall it was Euphausiacea. As a result of analyzing the feeding relationship between size groups and season groups, L. crocea showed significant differences in the interaction between size groups and season groups.

Development of Advanced Mechanical Analysis Models for the Bolted Connectors under Cyclic Loads (반복하중을 받는 볼트 연결부에 대한 역학적인 고등해석 모델의 개발)

  • Hu, Jong Wan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.33 no.1
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    • pp.101-113
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    • 2013
  • This paper intends to develop mechanical analysis models that are able to predict complete nonlinear behavior in the bolted connector subjected to cyclic loads. In addition, experimental data which were obtained from loading tests performed on the T-stub connections are utilized to validate the accuracy of analytical prediction and the adequacy of numerical modeling. The behavior of connection components including tension bolt uplift, bending of the T-stub flange, stem elongation, relative slip deformation, and bolt bearing are simulated by the multi-linear stiffness models obtained from the observation of their individual force-deformation mechanisms in the connection. The component springs, which involve the stiffness properties, are implemented into the simplified joint element in order to numerically generate the behavior of full-scale connections with considerable accuracy. The analytical model predictions are evaluated against the experimental tests in terms of stiffness, strength, and deformation. Finally, it can be concluded that the mechanical models proposed in this study have the satisfactory potential to estimate stiffness response and strength capacity at failure.

Effects of the Geometry of Components Attached to the Drain Valve on the Performance of Water Hammer Pumps

  • Saito, Sumio;Takahashi, Masaaki;Nagata, Yoshimi;Dejima, Keita
    • International Journal of Fluid Machinery and Systems
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    • v.4 no.4
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    • pp.367-374
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    • 2011
  • Water hammer pumps can effectively use the water hammer phenomenon in long-distance pipeline networks that include pumps and allow fluid transport without drive sources, such as electric motors. The results of experiments that examined the effect of the geometric form of water hammer pumps by considering their major dimensions have been reported. In addition, a paper has also been published analyzing the water hammer phenomenon numerically by using the characteristic curve method for comparison with experimental results. However, these conventional studies have not fully evaluated the pump performance in terms of pump head and flow rate, common measures indicating the performance of pumps. Therefore, as a first stage for the understanding of water hammer pump performance in comparison with the characteristics of typical turbo pumps, the previous paper experimentally examined how the hydrodynamic characteristics were affected by the inner diameter ratio of the drive and lifting pipes, the form of the air chamber, and the angle of the drive pipe. To understand the behavior of the components attached to the valve chamber and the air chamber that affects the performance of water hammer pumps, the previous study also determined the relationship between the water hammer pump performance and temporal changes in valve chamber and air chamber pressures according to the air chamber capacity. For the geometry of components attached to the drain valve, which is another major component of water hammer pumps, this study experimentally examines how the water hammer pump performance is affected by the length of the spring and the angle of the drain pipe.

Observation for drying non-uniformity of allium vegetables using NIR spectroscopy (근적외 분광법을 이용한 양념 야채의 건조 불균일성 관찰)

  • Cho, Hyeong Ho;Lee, Seon Mi;Park, Sang Wook;Cho, Rae Kwang
    • Food Science and Preservation
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    • v.21 no.6
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    • pp.838-843
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    • 2014
  • In this study, near-infrared spectroscopy was used to observe the drying non-uniformity of vegetables such as spring onions, onions, and garlic, which are commonly used for seasoning. For the warm-air convection drying method, the vegetables showed drying non-uniformity, which is due to the unevenness of the wind temperature and humidity depending on the height and position of the drying tray. The second derivative spectra between the vegetable samples with different drying degrees were compared. The peak at around 1,390~1,400 nm, which is assigned to weak hydrogen bonds of water, was changed during drying whereas the peak near 1,420 nm, which represents strong hydrogen (H-) bonds of water, was not changed, indicating that water with weak H-bonds evaporates first during drying, and that water with strong H-bonds remains after drying. The hyperspectral NIR imaging technique combined with principal-component analysis made it possible to discriminate the dried vegetables according to their drying degree.

The Effect of Tidal Cycle and River Runoff on the Dynamic of Nutrients in Keum river estuary (금강하구역에서 영양염 거동에 대한 조석 및 담수유출의 영향)

  • Kim, Jong-Gu;Kang, Hoon
    • Journal of Environmental Science International
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    • v.11 no.6
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    • pp.519-528
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    • 2002
  • This study was to evaluate the impact of river runoff and salt intrusion by tide on nutrient balance of estuary during a complete tidal cycle. 24 hours time series survey was carried out during a spring tide July 2001 on a tidal estuary in the Keum river. Three stations(A,B,C) were set along a transect line of about 10km, which linked the lower part of estuary dyke to the subtidal zone. Surface water was sampled simultaneously at each station every hours f3r the determination of nutrients. Water temperature, pH and dissolved oxygen were measured in situ. Riverine input of silicate and nitrate during ebb tide significantly increased the concentration of all stations. Conversely, during high tide, nutrient concentration were lowered by the mixing of fresh water with sea water Ammonium nitrogen concentration were higher at intertidal zone(Stn.B) due to sewage inflow to Kyeongpo stream and ammonium release under anaerobic conditions. Also, these results was discussed as a biological component that influences the processes of nutrient regeneration within the estuary. Best correlations were found at lower part of estuary dyke(Stn.A) for salinity against DIN(Y=0.121 Sal.+4.97, r2=0.956) and silicate(Y=0.040 Sal.+2.62, r2=0.785). But no significant correlation was found between salinity and ammonium. Unbalanced elemental ratio(N/P, Si/N and Si/P) depended significantly on the import of nutrients (silicate & nitrate nitrogen) from river and stream. The effect of the tidal cycle and river runoff is important that in determining the extend of the variations in nutrient concentrations at all station.

Analysis of Pollutant Characteristics in Nakdong River using Confirmatory Factor Modeling (확인적 요인모형을 이용한 낙동강 유역의 오염특성 분석)

  • Kim, Mi-Ah;Kang, Taegu;Lee, Hyuk;Shin, Yuna;Kim, Kyunghyun
    • Journal of Korean Society on Water Environment
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    • v.28 no.1
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    • pp.84-93
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    • 2012
  • The study was conducted to analyze the spatio-temporal changes in water quality of the major 36 sampling stations of Nakdong River, depending on each station, season using the 17 water quality variables from 2000 to 2010. The result was verified to interpret the characteristics of water quality variables in a more accurate manners. According to the Principal component analysis (PCA) and Exploratory factor analysis (EFA) results; the results of these analyses were identified 4 factors, Factor 1 (nutrients) included the concentrations of T-N, T-P, $NO_{3}-N$, $PO_{4}-P$, DTN, DTP for sampling station and season, Factor 2 (organic pollutants) included the concentrations of BOD, COD, Chl-a, Factor 3 (microbes) included the concentrations of F.Coli, T.Coli, and Factor 4 (others) included the concentrations of pH, DO. The results of a Cluster analysis indicated that Geumhogang 6 was the most contaminated site, while tributaries and most of the down stream sites of Nakdong River were mainly affected by each nutrients (Factor 1) and organic pollutants (Factor 2). The verification consequence of Confirmatory factor analysis (CFA) from Exploratory factor analysis (EFA) result can be summarized as follows: we could find additional relations between variables besides the structure from EFA, which we obtained through the second-order final modeling adopted in CFA. Nutrients had the biggest impact on water pollution for each sampling station and season. In particular, It was analyzed that P-series pollutant should be controlled during spring and winter and N-series pollutant should be controlled during summer and fall.

Seasonal Variation in Abundance and Species Composition of Fishes Collected by a Beam Trawl around Naro-do, Korea (남해 나로도 주변해역에서 조망에 채집된 어류의 종조성과 계절변동)

  • KIM Jong-Bin;CHANG Dae-Soo;KIM Yeong-Hye;KANG Chang-Keun;CHO Kyu-Dae
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.4
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    • pp.378-388
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    • 2003
  • Seasonal variations in abundance and species composition of fish assemblage around Narodo were examined. Fish samples were monthly collected by a beam trawl from December 2000 to November 2001. A total of 62 fish species representing 37 families were collected. Of these, Thryssa kammalensis, T. hamiltoni, Chaeturichthys hexanema, Johnius grypotus, Leiognathus nuchalis, Cynoglossus robustus and Setipinna taty were dominant species comprising $82\%$ of the total number of individuals. Species diversity indices ranged from 1.2 to 2.2 showing the highest values from September to November 2001. The fish assemblage was divided into three different groups by cluster analysis of the fourteen dominant species. The main residence species were J. grypotus, L. nuchalis, C. hexanema, C. robustus, Setipinna tenuifilis, T. kammalensis and Ctenotrypauchen microcephalus. Of the temporal species T. hamiltoni, Liparis tanakai and Erisphex pottii were collected In spring, and Muraenesox cinereus and Trichiurus lepturus were in summer and autumn. Principal component analysis revealed that seasonal variation in the fish assemblage was attributed to the abundance of temporal species due to seasonal variation of environmental factors such as water temperature and ecological pattern (polagic/demersal) of fish species.