• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.19-25
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• 1992

The study was carried out to investigate the correlation between the heavy metals emitted by the motor vehicles with the heavy traffic road side environment (soil, leave, bark, ambient air). The Pb, Cu, Zn contents in road side soil sand leaves, barks from Ginkgo, biloba and ambient air adjacent to the heavy traffic road side from June to August, 1992 Suwon city were analyzed by Atomic absorption spectrometry and Inductively coupled plasma emission spectrophotometry. The results were as follows: 1) The high levels of heavy metals concentration were Pb, at city-terminal in soil (186 $\mu$g/g), Cu, at city-terminal in soil (221 $\mu$g/g), Zn, at city-terminal in ambient air (252 $\mu$g/m$^{3}$). 2) The low leves of heavy metals concentration were Pb, at North-gate in ambient air (1.65$\mu$g/m$^{3}$), Cu, at North-gate in ambient air (4 $\mu$g/m$^{3}$), Zn, at North-gate in ambient air (15.31$\mu$g/m$^{3}$). 3) The regional distribution of Pb, Cu, Zn in road side soils, leaves and barks from Ginkgo, biloba, ambient air show high levels in turn, city4erminal, Guan Sean Dong, South gate, North gate. 4) The concentration of heavy metals (Pb, Cu, Zn) in soils, leaves, barks, ambient air was highly correlated with the traffic volume of the sampling sites (r=0.64~0.96). To conclude that the high levels of Pb, Cu, Zn contaminations were positively related to motor vehicles-borne pollutants and road side soils, trees, ambient air adjacent to a high density building area with low road coverage and heavy traffic volume were reflected strongly by the hazardous pollutants emitted by motor vehicles.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.6
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• pp.908-913
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• 1999

This experiment was conducted in three trials to evaluate optimal ambient temperature for a novel milk replacer feeding system designed for early-weaned pigs, compared to commercial dry diets fed within a conventional hot nursery. A total of 165 PIC genotype pigs were weaned at $13.89{\pm}0.7$ days of age and allotted to one of two dietary treatments in three trials based on weight and litter origin. Each trial consisted of pigs fed dry diets (DD) and pigs fed milk replacer (MR) which was offered in one of 3 different ambient temperatures. Pigs fed milk replacer were housed in a specialized nursery building in which one half of each pen contained an enclosed hover that was thermostatically maintained at $32^{\circ}C$ while the exterior ambient temperature (where milk was fed) was set at either 17 (trial 1), 24 (trial 2) or $32^{\circ}C$ (trial 3). Pigs fed dry diets with the conventional nursery were maintained at $30^{\circ}C$ for each trial. From d 21 to d 49, all pigs were fed DD within a standardized hot nursery environment. During the first week (d 14-21), pigs fed MR showed increased ADG from 214% to 228% over control pigs fed DD (p<0.001), regardless of ambient temperature. As ambient temperature was increased from 17 to 24 to $32^{\circ}C$, ADG of MR-fed pigs was increased by 214%, 220% and 228% over those of pigs fed DD, respectively. ADFIs of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were increased by 108%, 139% and 164% from d 14 to d 21, respectively. Fed efficiency (G/F) of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were 199%, 162% and 139% of those of pigs fed DD, respectively. As ambient temperature increased, diarrhea scores showed a slight tendency to increase. The advantage of MR feeding was greater when the ambient temperature was higher, but G/F was impaired with increased ambient temperature. We conclude that ambient temperature within the specialized nursery influenced behavior, MR feed intake, and probably piglet energy expenditure. There were no differences between MR-fed and DD-fed pigs for ADG, ADFI and G/F in the subsequent growth period (d 21 to d 49, p>0.05). Maximal advantage of MR feeding was obtained at the intermediate ($24^{\circ}C$) ambient temperature during the overall period (p<0.05). Results from this experiment indicate that a milk replacer feeding system utilized in the early postweaning period can maximize pig growth performance, and that ADG, ADFI and G/F were affected by different ambient temperatures within MR-fed pigs. The high or low temperatures could not support the maximal growth of pigs fed MR.

• Journal of the Korean Society of Safety
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• v.5 no.2
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• pp.40-49
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• 1990

For the determination of polluant NOx in ambient air, nitrate ion-selective electrode(ISE) was made. To comparison of NOx in each method, the nitrate-ISE, NEBA, Orion electrode were used to determinee NOx in ambient air. In this work, the concentration of NOx in ambient air was average 0.06ppm. The results were good agreement with those obtained by each method within a relative error of 3％, Absorbing efficiency of nitrogen oxides in ambient air was good for Alkali solution. The determination of nitrogen oxides in ambient air using the Aliquat 336N-PVC membrane electrode was one of the useful method. The best characteristics of the Aliquat 336N-PVC me,mbrane electrode were obtained with the ion-exchanger concentration level of 6.5-9.1 percent by weight. The optimal membrane composition, was 9.09wt.％ of ion-exchanger, 30.95wt.％ of PVC, 60.6wt.％ of plasticizer (DBP), and 0.5mm of thickness. Under the above condition, the electrode approached the Nernstian slope most closely, and the linear response ranges produced the best results.

• Korean Journal Plant Pathology
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• v.14 no.6
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• pp.720-724
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• 1998

Open-top field chamber study was carried out to investigate effect of ambient ozone level on the yield of rice cultivar 'Dongjin' in Kwangyang area located in the vicinity of the industrial complex of Yechon petrolium refinery and chemical works or Kwangyang Iron and Steel works during the summer of 1997. mean ozone concentration of ambient air during daytime (9:00∼17:00) was revealed to exceed over 40 ppb which is defined to be a critical level causing plant injury and yield reduction in Europe. Yield component analysis showed that there was no significant difference in rice yield between ambient air and charcoal-filtered air. The results suggest that the ambient ozone levels during the exposure period had no effect on yield reduction of rice cultivar 'Dongjin' and it is likely that the cultivar is tolerant to ambient ozone levels.

• Journal of the Korean Ceramic Society
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• v.36 no.11
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• pp.1189-1197
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• 1999

Low-density silica gel monolith was synthesized at ambient pressure by surface modification with TMCS and sub-sequent heat treatment. The mechanical thermal and optical properties of gel were studied. Compressive strength and modulus of compression of 350$^{\circ}C$-heated gel with the density of 0.24g/cm3 were 250kPa and 0.2MPa respectively. The thermal conductivity of silica gels synthesized at ambient pressure exhibited 0.02 W/m$.$K for the density of 0.24g/cm3 which is similar to that of the gel via supercritical drying and their main thermal transfer mechanism is considered to be solid and radiation conduction at room temperature. Ambient-dried silica gels were transparent blue showing about 60% of transmittance in the wavelength of 1500-2100nm and typical absorption bands of existing bonds under heat treatment at 350$^{\circ}C$. Medium scale monolity(${\Phi}$=50mm) at ambient pressure could be successfully prepared through total 5-month process period.

• The Research Journal of the Costume Culture
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• v.10 no.6
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• pp.793-801
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• 2002

The effects of ambient air temperature on the clothing ventilation were investigated numerically by a finite difference method. Numerical analysis using a 2-dimensional model comprising the air space between the skin and the clothing was conducted under the assumption that the clothing ventilation occurred only through the openings not through the fabric. The larger the temperature difference between the skin and the surroundings, the more apparent the thermal boundary layer As the ambient air temperature decreased, the air flow and the rate of the return of oxygen concentration to the atmosphere level in the clothing increased. Convection was dominant under low ambient air temperature, whereas conduction was dominant under high ambient air temperature. The ventilation rate was faster in the clothing microenvironment of the body part than that of the arm part.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.03a
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• pp.49-54
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• 2002

This paper describes a systematic way of simultaneously identifying the ambient pore pressure and the rigidity index (=G/s$\_$u/) of soil by applying an optimization technique to the piezocone dissipation test result. An ambient pore pressure and optimal rigidity index were determined by minimizing the differences between theoretical excess pore pressures developed by Randolph ＆ Wroth(1979) and measured excess pore pressures from piezocone using optimization technique. The effectiveness of the proposed back-analysis method was examined against the well-documented performance of piezocone dissipation tests (Tanaka ＆ Sakagami, 1989), from the viewpoints of proper determination of selected target parameters and saving of test duration. It is shown that the proposed back-analysis method can evaluate properly the ambient pore pressure and the rigidity index by using only the early phase of the dissipation test data. Also, it is shown that with the optimized rigidity index and ambient pore pressure the proposed back-analysis method permits the horizontal coefficient of consolidation to be identified rationally.

• Transactions of the Korean Society of Automotive Engineers
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• v.8 no.2
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• pp.27-32
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• 2000

The main objective of this work is to investigate the effect of ambient conditions on the spray behavior and spray characteristics of high-pressure fuel injector. For this purpose, the effects of ambient pressure and temperature on the spray characteristics have been studied by applying the analysis of visualization system and phase Doppler particle analyzer. In this experiment, the visualization of spray behavior was performed under various ambient gas conditions and injection parameters such as gas temperature, ambient pressure, injection pressure of injector, and axial distance from the nozzle tip. Based on the investigation results, the spray tip penetration and spray width decrease with the increase of ambient gas pressure in the spray chamber. The effects of the spray parameters on the microscopic characteristics of gasoline spray were discussed.

• Mass Spectrometry Letters
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• v.14 no.4
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• pp.121-140
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• 2023

It is becoming more and more clear that each cell, even those of the same type, has a unique identity. This sophistication and the diversity of cell types in tissue are what are pushing the necessity for spatially distributed omics at the single-cell (SC) level. Single-cell chemical assessment, which also provides considerable insight into biological, clinical, pharmacodynamic, pathological, and toxicity studies, is crucial to the investigation of cellular omics (genomics, metabolomics, etc.). Mass spectrometry (MS) as a tool to image and profile single cells and subcellular organelles facilitates novel technical expertise for biochemical and biomedical research, such as assessing the intracellular distribution of drugs and the biochemical diversity of cellular populations. It has been illustrated that ambient mass spectrometry (AMS) is a valuable tool for the rapid, straightforward, and simple analysis of cellular and sub-cellular constituents and metabolites in their native state. This short review examines the advances in ambient mass spectrometry (AMS) and ambient mass spectrometry imaging (AMSI) on single-cell analysis that have been authored in recent years. The discussion also touches on typical single-cell AMS assessments and implementations.

• Smart Structures and Systems
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• v.15 no.2
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• pp.447-468
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• 2015

Modal identification of civil engineering structures based on ambient vibration measurement has been widely investigated in the past decades, and a variety of output-only operational modal identification methods have been proposed. However, vibration modes, even fundamental low-order modes, are not always identifiable for large-scale structures under ambient vibration excitation. The identifiability of vibration modes, deficiency in modal identification, and criteria to evaluate robustness of the identified modes when applying output-only modal identification techniques to ambient vibration responses were scarcely studied. In this study, the mode identifiability of the cable-stayed Ting Kau Bridge using ambient vibration measurements and the influence of the excitation intensity on the deficiency and robustness in modal identification are investigated with long-term monitoring data of acceleration responses acquired from the bridge under different excitation conditions. It is observed that a few low-order modes, including the second global mode, are not identifiable by common output-only modal identification algorithms under normal ambient excitations due to traffic and monsoon. The deficient modes can be activated and identified only when the excitation intensity attains a certain level (e.g., during strong typhoons). The reason why a few low-order modes fail to be reliably identified under weak ambient vibration excitations and the relation between the mode identifiability and the excitation intensity are addressed through comparing the frequency-domain responses under normal ambient vibration excitations and under typhoon excitations and analyzing the wind speeds corresponding to different response data samples used in modal identification. The threshold value of wind speed (generalized excitation intensity) that makes the deficient modes identifiable is determined.