• ETRI Journal
• /
• v.45 no.3
• /
• pp.519-533
• /
• 2023

This paper implements a simultaneous solar and thermal energy harvesting system, as a hybrid energy harvesting (HEH) system, to convert ambient light into electrical energy through photovoltaic (PV) cells and heat absorbed in the body of PV cells. Indeed, a solar panel equipped with serially connected thermoelectric generators not only converts the incoming light into electricity but also takes advantage of heat emanating from the light. In a conventional HEH system, the diode block is used to provide the path for the input source with the highest value. In this scheme, at each time, only one source can be handled to generate its output, while other sources are blocked. To handle this challenge of combining resources in HEH systems, this paper proposes a method for collecting all incoming energies and conveying its summation to the load via the current mirror cells in an approach similar to the maximum power point tracking. This technique is implemented using off-the-shelf components. The measurement results show that the proposed method is a realistic approach for supplying electrical energy to wireless sensor nodes and low-power electronics.

• Tuberculosis and Respiratory Diseases
• /
• v.42 no.3
• /
• pp.322-331
• /
• 1995

Introduction: This study was performed to evaluate the diagnostic usefulness of simultaneous determination of 3 tumor markers {serum carcinoembryonic antigen(CEA), squamous cell carcinoma antigen (SCC Ag) and neuron specific enolase(NSE)} in lung cancer patients. Method: In 113 patients with primary lung cancer(70 with squamous cell carcinoma, 30 with adenocarcinoma, 13 with small cell carcinoma) and 103 patients with benign lung diseases, serum CEA and NSE were measured by enzyme immunoassay, and SCC Ag was measured by microparticle enzyme immunoassay. Results: 1) The mean serum levels of 3 tumor markers were significantly higher in lung cancer groups than benign lung disease groups respectively(p=0.001). 2) In squamous cell carcinoma, the SCC Ag was elevated in 67%, in adenocarcinoma CEA was elevated in 77% and in small cell carcinoma NSE was elevated in 77%, but there were no significant differences according to the stage of each cancer cell types. 3) CEA was the most sensitive marker, but nonspecific to cancer types. SCC Ag was less sensitive than other markers, but more specific toward squamous cell carcinoma, and NSE was more specific to primary lung cancer. 4) As the number of positive tumor markers was increased, the relative possibility of lung cancer was also increased. If two markers were positive, it increased to 77%, and if three markers were positive it increased to 90%. Conclusion: The simultaneous measurement of serum CEA, SCC Ag and NSE would provide additional information for the diagnosis of lung cancer.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
• /
• 2001.06a
• /
• pp.1523-1523
• /
• 2001

The wine industry requires practical methods for objectively measuring the composition of both red wine grapes on the vine to determine optimal harvest time; and of freshly harvested grapes for efficient allocation to vinery process streams for particular red wine products, and to determine payment of contract grapegrowers. To be practical for industry application these methods must be rapid, inexpensive and accurate. In most cases this restricts the analyses available to measurement of TSS (total soluble solids, predominantly sugars) by refractometry and pH by electropotentiometry. These two parameters, however, do not provide a comprehensive compositional characterization for the purpose of winemaking. The concentration of anthocyanin pigment in red wine grapes is an accepted indicator of potential wine quality and price. However, routine analysis for total anthocyanins is not considered as a practical option by the wider wine industry because of the high cost and slow turnaround time of this multi-step wet chemical laboratory analysis. Recent work by this ${group}^{l,2}$ has established the capability of near infrared (NIR) spectroscopy to provide rapid, accurate and simultaneous measurement of total anthocyanins, TSS and pH in red wine grapes. The analyses may be carried out equally well using either research grade scanning spectrometers or much simpler reduced spectral range portable diode-array based instrumentation. We have recently expanded on this work by collecting thousands of red wine grape samples in Australia. The sample set spans two vintages (1999 and 2000), five distinct geographical winegrowing regions and three main red wine grape varieties used in Australia (Cabernet Sauvignon, Shiraz and Merlot). Homogenized grape samples were scanned in diffuse reflectance mode on a FOSE NIR Systems6500 spectrometer and subject to laboratory analysis by the traditional methods for total anthocyanins, TSS and pH. We report here an analysis of the correlations between the NIR spectra and the laboratory data using standard chemometric algorithms within The Unscrambler software package. In particular, various subsets of the total data set are considered in turn to elucidate the effects of vintage, geographical area and grape variety on the measurement of grape composition by NIR spectroscopy. The relative ability of discrete calibrations to predict within and across these differences is considered. The results are then used to propose an optimal calibration strategy for red wine grape analysis.

• The Korean Journal of Nuclear Medicine
• /
• v.23 no.1
• /
• pp.55-61
• /
• 1989

While cisplatin has been widely used in the treatment of a variety of cancers, nephrotoxicity is one of the major problems which frequently limit clinical usefulness of cisplatin. This study has been conducted to investigate nephrotoxicity of cisplatin in terms of changes in glomerular filtration rate (GFR) and effective renal plasma flow (EFPF) measured by the simultaneous use of $^{99m}Tc-DTPA$ and $^{131}I-OIH$, before and after administration of cisplatin, in 12 patients with lung cancer and four patients with esophageal cancer. Cisplatin was administrated at total doses of $75\sim100mg/m^2$ with two hour hydration and diuresis method. GFR determined by the use of $^{99m}Tc-DTPA$ had a good correlation with 24-hour creatinine clearance rate (r=0.77, p<0.001). GFR and filtration fraction decreased immediately after administration of cisplatin, however, they showed a tendency to be in completely recovered four weeks after administration. ERPF was not changed immediately after and four weeks after administration of cisplatin. GFR before and immediately after administration of cisplatin were analyzed with regard to age, sex, performance status, previous adminstration of cisplatin and method of administration. None of these factors had any influence on the rate of decrease in GFR except method of administration. Administration of cisplatin as a single dose lowered GFR more compared with that as divided doses. In this study, we have also demonstrated that the simultaneous use of $^{99m}Tc-DTPA$ and $^{131}I-OIH$ was a useful tool for the measurement of GFR and ERPF respectively.

• The Journal of Internal Korean Medicine
• /
• v.39 no.4
• /
• pp.495-510
• /
• 2018

Objective: This study was designed to investigate the possibility of quantification of the diagnosis of abdominal coldness (AC) in patients with functional dyspepsia (FD). Methods: Forty-four patients with FD were enrolled in this study. Three Korean medicine doctors each randomly examined all abdomens. Diagnosis of AC was made by consensus of at least two of the doctors. Body temperature (oral by digital oral thermometer) and skin temperature (by digital infrared thermal imaging [DITI]) were measured, followed by administration of the Cold and Heat questionnaire (CHQ) and the Instrument of Pattern Identification for Functional Dyspepsia (IPIFD). Results: Of the 44 patients with FD, 22 were assigned to the AC group and 22 to the non-AC group. The concordance rate of diagnosis among the three doctors was 63.6% (28/44), with a ${\kappa}$ of 0.504, indicating means moderate agreement). Neither the oral nor the skin temperatures showed statistically significant differences between the AC and non-AC groups. However, the CHQ scores and 'Simultaneous Occurrence of Cold and Heat Syndromes pattern' scores of the IPIFD were higher in AC group and showed statistically significant differences (p=0.010 and 0.009). Conclusions: This is the first study conducting quantitative measurements of abdominal coldness in patients with FD. Although oral and skin temperature showed no statistical significance between AC and non-AC groups, the concordance rate of diagnosis of AC among the three Korean Medicine doctors was moderate. The CHQ scores and 'Simultaneous Occurrence of Cold and Heat Syndromes pattern' scores of the IPIFD also suggest that diagnosis of AC is relevant to cold and heat patterns, and these questionnaires could be utilized as supportive data for the diagnosis of AC. Further studies should be conducted for the purpose of quantifying and standardizing abdominal examinations in Korean Medicine.

• Journal of Korean Society of Occupational and Environmental Hygiene
• /
• v.4 no.2
• /
• pp.189-197
• /
• 1994

Analytic methods for Cr(VI) level in industrial hygienic field were suggested by the National Institute for Occupational Safety and Health(NIOSH method 7600, 7604). There were growing needs for measurement of Cr(III) and Cr(VI) levels simultaneously. Two analytical methods were suggested to determine Cr(III) and Cr(VI) levels simultaneously. The one is method by using reversed phase high peformance liquid chromatography(HPLC) and the other is by using ion exchange HPLC. The purpose of this work was to evaluate the usefulness of these two analytic methods. For the difference of ionic charges of Cr(III)-ethylendiamine tetraacetic acid(EDTA) chelate and $CrO_4{^-2}$, we could detect them simultaneously by ion exchange HPLC. Also, we attempted to determine the levels of Cr(III) and Cr(VI) chelated with sodium diethyldithiocarbamate(NaDDTC) by using reversed phase HPLC. The confirmation of Cr(III) and Cr(VI) were checked by fraction collector and nameless atomic absorption spectrometer. The optimal conditions for the formation of Cr(III)-EDTA chelate were two hours incubation period with pH 5. Cr(III)-EDTA and Cr(VI) in EDTA solution were successfully separated by anion exchange column using $Na_2CO_3/NaOH$ mixture as mobile phase. Peaks of Cr(III)-EDTA and Cr(VI) in EDTA were identified at 5 minutes and 7 minutes of retention time respectively by the ion exchange HPLC. The formation of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were twelve hours incubation period. Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates were separated by reversed phase column using methanol and water mixture as mobile phase. Peaks of Cr(VI)NaDDTC and Cr(III)-NaDDTC chelates were identified at 13 minutes and 26 minutes of retention time respectively by the reversed phase HPLC. Due to reduction of Cr(VI) to Cr(III), it seems to be not suitable for simultaneous determination of Cr(III)-NaDDTC and Cr(VI)-NaDDTC chelates by reversed phase HPLS. Simultaneos determination of Cr(III) and Cr(VI) by ion exchange HPLC was more accurate and simple method.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.4
• /
• pp.536-542
• /
• 2007

The responses of whole body protein and glucose kinetics and of nitrogen (N) metabolism to non-protein energy intake (NPEI) were determined using an isotope dilution approach and measurement of N balance in three adult male goats. The diets containing 1.0, 1.5 and 2.0 times ME maintenance requirement, with fixed intake of CP (1.5 times maintenance) and percentage of hay (33%), were fed twice daily for each 21 d experimental period. After an adaptation period of 11 d, N balance was determined over 3 d. On day 17, whole body protein synthesis (WBPS) and glucose irreversible loss rate (ILR) were determined during the absorptive state by a primed-continuous infusion of [$^2H_5$]phenylalanine, [$^2H_2$]tyrosine, [$^2H_4$]tyrosine and [$^{13}C_6$]glucose, with simultaneous measurements of plasma concentrations of metabolites and insulin. Ruminal characteristics were also measured at 6 h after feeding over 3 d. Nitrogen retention tended to increase (p<0.10) with increasing NPEI, although digestible N decreased linearly (p<0.05). Increasing NPEI decreased (p<0.01) ammonia N concentration, but increased acetate (p<0.05) and propionate (p<0.05) concentrations in the rumen. Despite decreased plasma urea N concentration (p<0.01), increased plasma tyrosine concentration (p<0.05), and trends toward increased plasma total amino N (p<0.10) and phenylalanine concentrations (p<0.10) were found in response to increasing NPEI. Increasing NPEI increased ILR of both glucose (p<0.01) and phenylalanine (p<0.05), but did not affect ($p{\geq}0.10$) that of tyrosine. Whole body protein synthesis increased (p<0.05) in response to increasing NPEI, resulting from increased utilization rate for protein synthesis (p<0.05) and unchanged hydroxylation rate of phenylalanine ($p{\geq}0.10$). These results suggest that increasing NPEI may enhance WBPS and glucose turnover at the absorptive state and improve the efficiency of digestible N retention in goats, with possibly decreased ammonia and increased amino acid absorption. In addition, simultaneous increases in WBPS and glucose ILR suggest stimulatory effect of glucose availability on WBPS, especially when sufficient amino acid is supplied.

• Journal of the Korean Chemical Society
• /
• v.18 no.1
• /
• pp.40-46
• /
• 1974

The fission neutron reactions of $^{47}Ti(n.p)^{47}Sc$ and $^{93}Nb(n,{\alpha})^{90m}Y$, along with epicadmium neutron reaction of $^{96}Zr(n,{\gamma})^{97}Zr$ were used for the simultaneous determination of Ti, Nb and Zr in synthetic mixture. Prior to neutron irradiation, Ti, Zr and Nb in the mixture were separated together in one group through the cation exchange column of Dowex $50{\times}8$ resin using 0.5 M ${\alpha}$-hydroxy-iso-butyric acid as the eluent. After irradiation of the eluate the product nuclides, $^{97}Zr$, ^{47}Sc$ and ^{90m}Y$, were eluted sequentially through the same column with 0.5 M ${\alpha}$-HIBA, 0.5 M ${\alpha}$-HIBA-1 N HNO_3 and 0.5 M ${\alpha}$-HIBA-2 N HNO_3$ solution, respectively. The gamma-ray spectrometry was used for the measurement of the gamma-ray activities of the eluted nuclides. The detection limits of Nb, Ti and Zr were found to be 0.2 %, 0.01 % and 0.002 %, respectively.

• Korean Journal of Soil Science and Fertilizer
• /
• v.42 no.5
• /
• pp.399-407
• /
• 2009

Laser induced breakdown spectroscopy(LIBS) is an simple analysis method for directly quantifying many kinds of soil micro-elements on site using a small size of laser without pre-treatment at any property of materials(solid, liquid and gas). The purpose of this study were to find an optimum condition of the LIBS measurement including wavelengths for quantifying soil elements, to relate spectral properties to the concentration of soil elements using LIBS as a simultaneous un-breakdown quantitative analysis technology, which can be applied for the safety assessment of agricultural products and precision agriculture, and to compare the results with a standardized chemical analysis method. Soil samples classified as fine-silty, mixed, thermic Typic Hapludalf(Memphis series) from grassland and uplands in Tennessee, USA were collected, crushed, and prepared for further analysis or LIBS measurement. The samples were measured using LIBS ranged from 200 to 600 nm(0.03 nm interval) with a Nd:YAG laser at 532 nm, with a beam energy of 25 mJ per pulse, a pulse width of 5 ns, and a repetition rate of 10 Hz. The optimum wavelength(${\lambda}nm$) of LIBS for estimating soil and plant elements were 308.2 nm for Al, 428.3 nm for Ca, 247.8 nm for T-C, 438.3 nm for Fe, 766.5 nm for K, 85.2 nm for Mg, 330.2 nm for Na, 213.6 nm for P, 180.7 nm for S, 288.2 nm for Si, and 351.9 nm for Ti, respectively. Coefficients of determination($r^2$) of calibration curve using standard reference soil samples for each element from LIBS measurement were ranged from 0.863 to 0.977. In comparison with ICP-AES(Inductively coupled plasma atomic emission spectroscopy) measurement, measurement error in terms of relative standard error were calculated. Silicon dioxide(SiO2) concentration estimated from two methods showed good agreement with -3.5% of relative standard error. The relative standard errors for the other elements were high. It implies that the prediction accuracy is low which might be caused by matrix effect such as particle size and constituent of soils. It is necessary to enhance the measurement and prediction accuracy of LIBS by improving pretreatment process, standard reference soil samples, and measurement method for a reliable quantification method.

• Journal of Nutrition and Health
• /
• v.24 no.3
• /
• pp.199-205
• /
• 1991

Retinoic acid. the active metabolite of vitamin A. was detected in the human liver for the first time using a new method. A rapid and sensitive technique has been developed using gradient-elution. reverse-phase high performance liquid chromatography. This assay. with simultaneous multiwavelength detection at 294nm, 325nm and 450nm after saponifcation of liver samples. allows us seperation and quantitation of vitamin E, retinoic acid, total retinoids and various carotenoids in one small sample. The proportion of retinoic acid to total retinoids in human liver appears to be quite $consistent(2.4\pm0.2%$ ). With low vitamin A storage in liver, detection at another wavelenth 354nm would increase the sensitivity for retinoic acid of small quantity This method of analysis could be used for other tissues like red blood cells, plasma or serum, also. Hepatic retinoic acid level with total retinoids and carotenoids would serve a better indicator of functional vitamin A nutriture especially for those with disease requiring needle biopsy of liver.