• Journal of Biosystems Engineering
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• v.32 no.1 s.120
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• pp.37-43
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• 2007

This study was carried out to investigate the applicability of PVC membrane-based ion-selective electrodes for macronutrients (K, Ca, and N) by measuring of potassium, calcium, nitrate ions in hydroponic nutrient solution. The capabilities of two ion-selective membranes with varying chemical compositions for each ion were evaluated in terms of sensitivity, selectivity, and lifetime to choose sensing elements suitable for measuring typical ranges of nutrient concentrations in hydroponic solutions. The selected calcium and nitrate ion-selective membranes showed effectively sensitive responses to calcium and nitrate ions with lifetimes of 25 and 15 days, respectively. The addition of a cation additive to the potassium membrane cocktail allowed its sensitivity to be increased whereas its lifetime was reduced from 30 days to 10 days.

• Korean Institute of Interior Design Journal
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• v.25 no.2
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• pp.41-49
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• 2016

The purpose of this study is to analyze the change and to compare to the difference of 'selective elements' and 'space-memory' focusing on the theory, 'selective attention' through the survey results. In this study, In this study, the lighting is considered a important factor in the change of 'selective elements'. this survey is to find the selective elements of participants and to measure the spatial sensitivity of respondents through 'self- test'. The analysis in this study is conducted by descriptive statistics, t-test and one way ANOVA by SPSS program 22. The results of this study are as following; Firstly, 'attention-element' could be classified with 4 types, 'shape', 'material', 'contrast' and 'combination'. 'shape' could divide into 'structure' and' furniture and object'. In case of 'material', it could section with 'pattern' and 'color'. Secondly, through the results of study, 'attention-element' is different each space during the day in detail. But we could know that 'shape' is the important element of the 'attention-elements' during the day through comparison of this result. That means users consider this as a important factor when they evaluate the space. Therefore, it is effective way designers to consider 'shape' as the first element when they want to conduct the special sensitivity of users in the space through planning. On the other hand, what selective elements of users are different by the lighting situation should be acknowledged by designers. And they should think the kinds of selective elements are more various when lighting turns on than turns off.. Thirdly, through the results such as the meaningful difference of space-memory of users according to the change of 'attention-elements', designers should judge about which kind of feeling of users to the space do you want lead in the design process. For the effective feedback between spaces and users to induce the same emotion of users, designers need to consider the unified design and the individual design both. Also, we will regard the differences in the users' emotion to the space according to the lighting situation when we design the space.

• Journal of Food Hygiene and Safety
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• v.31 no.3
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• pp.222-225
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• 2016

In this study, the performance of five selective media for coliform bacteria was evaluated. In total, 83 coliform isolates from ready-to-eat food and 21 reference strains were inoculated in five agar media : Chromocult coliform agar (Merck Millipore), HiCrome coliform agar (Sigma), CHROMagar ECC chromogenic media, Brilliance E. coli/coliform selective agar (OXOID), and endo agar (Merck Millipore). Coliform isolates and reference strains were inoculated on the selective media to test media sensitivity and specificity. The tested media showed the following sensitivities for the isolated strains: Chromocult coliforms agar and HiCrome coliform agar, 94%; Brilliance E. coli/coliform selective agar, 93%; CHROMagar ECC chromogenic media, 92%; and endo agar, 74%. In addition, all media showed 100% specificity, except for endo agar (71%). Moreover Chromocult coliform agar and HICrome coliform agar showed high levels recovery. Taken together, these results identified Chromocult coliform agar and HICrome coliform agar as an effective selective medium for coliforms with higher sensitivity and specificity compared to other media tested in this study.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.4
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• pp.255-262
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• 2013

In this paper, a shape design sensitivity analysis(DSA) method is presented for Mindlin plates using an isogeometric approach. The isogeometric method possesses desirable advantages; the representation of exact geometry and the higher order inter-element continuity, which lead to the fast convergence of solution as well as accurate sensitivity results. Unlike the finite element methods using linear shape functions, the isogeometric method considers the exact normal vector and curvature of the CAD geometry, taking advantages of higher order NURBS basis functions. A selective reduced integration(SRI) technique is incorporated to overcome the difficulty of 'shear locking' phenomenon. This simple technique is surprisingly helpful for the accuracy of the isogeometric shape sensitivity without complicated formulation. Through the numerical examples of plate bending problems, the accuracy of the proposed isogeometric analysis method is compared with that of finite element one. Also, the isogeometric shape sensitivity turns out to be very accurate when compared with finite difference sensitivity.

• ETRI Journal
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• v.34 no.2
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• pp.216-225
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• 2012

This paper presents a transceiver module for human body communications whereby a spread signal with a group of 64 Walsh codes is directly transferred through a human body at a chip rate of 32 Mcps. Frequency selective digital transmission moves the signal spectrum over 5 MHz without continuous frequency modulation and increases the immunity to induced interference by the processing gain. A simple receiver structure with no additional analog circuitry for the transmitter has been developed and has a sensitivity of 250 ${\mu}V_{pp}$. The high sensitivity of the receiver makes it possible to communicate between mobile devices using a human body as the transmission medium. It enables half-duplex communication of 2 Mbps within an operating range of up to 170 cm between the ultra-mobile PCs held between fingertips of each hand with a packet error rate of lower than $10^{-6}$. The transceiver module consumes 59 mA with a 3.3 V power supply.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.405-408
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• 2007

Vestibular hair cells, the sensory receptors of vestibular organs, selectively amplify miniscule stimuli to attain high sensitivity. Such selective amplification results in compressive nonlinear sensitivity, which plays an important role in expanding dynamic range while ensuring robustness of the system. In this study, negative stiffness mechanism, a mechanism responsible for the selective amplification by vestibular hair cells, is applied to a simple mechanical system consisting of an array of inverted pendulums. The structure and working principle of the system have been inspired by gating spring hypothesis proposing that opening and closing of transduction channels contributes to the global stiffness of vestibular hair bundle. Parameter study was carried out to analyze the effect of each parameter on the compressive nonlinearity of suggested model.

• Bulletin of the Korean Chemical Society
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• v.31 no.9
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• pp.2537-2541
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• 2010

We chose a fluorescent pentapeptide sensor (-CPGHE) containing a dansyl fluorophore as a model peptide and investigated whether the selectivity and sensitivity of the peptides for heavy and transition metal ions could be tuned by changing amino acid sequence. In this process, we developed a selective peptide sensor, Cp1-d (-HHPGE, $K_d\;=\;670\;nM$) for detection of $Zn^{2+}$ in 100% aqueous solution and a selective and sensitive peptide sensor, Cp1-e (-CCHPGE, $K_d\;=\;24\;nM$) for detection of $Cd^{2+}$ in 100% aqueous solution. Overall results indicate that the selectivity and sensitivity of the metallopeptide sensors to specific heavy and transition metal ions can be tuned by changing amino acid sequence.

• Biomedical Science Letters
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• v.24 no.4
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• pp.390-397
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• 2018

For the specific detection of human Parvovirus B19 (HuPaV-B19), we designed ten specific PCR primers from 3,800~4,500 nucleotides of HuPaV-B19 complete genome (NC_000883.2). Seventeen candidate PCR primer sets for specific detecting HuPaV-B19 were constructed. In specific reaction of HuPaV-B19, seventeen PCR primer sets showed specific band, however five PCR primer sets were selected basis of band intensity, amplicon size and location. In non-specific reaction with seven reference viruses, four PCR primer sets showed non-specific band, however one PCR primer set is not. Detection sensitivity of final selective PCR primer set was $100fg/{\mu}L$ for 112 minute, and PCR amplicon is 539 base pairs (bp). In addition, nested PCR primer set was developed, for detection HuPaV-B19 from a low concentration of contaminated samples. Selection of nested PCR primer set was basis of sensitivity and groundwater sample tests. Detection sensitivity of final selective PCR and nested PCR primer sets for the detection of HuPaV-B19 were $100fg/{\mu}L$ and $100ag/{\mu}L$ basis of HuPaV-B19 plasmid, it was able to rapid and highly sensitive detection of HuPaV-B19 than previous reports. We expect developed PCR primer set in this study will used for detection of HuPaV-B19 in various samples.

• Vacuum Magazine
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• v.5 no.1
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• pp.9-12
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• 2018

Electronic nose has been developed for detection of various hazardous molecules, especially vapor organic compounds (VOCs), by adsorption and desorption phenomenon. However, although conventional electronic noses have provided many advantages such as simple detection and high sensitivity, they still need advanced technologies for selective specificity in real samples. In this review, we provide bionanoelectronic noses with natural receptors for selective odorant detection. This review includes from fabrication of natural receptors and conducting nanomaterials to bioelectronic noses. We also discussed their perspective applications for the future at the conclusion.

• Korean Journal of Clinical Laboratory Science
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• v.46 no.4
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• pp.140-142
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• 2014

To evaluate the recovery rates to increase toxigenic C. difficile, the selective enrichment broth culture methods were compared with commonly used cytotoxin assays and toxigenic culture. First, the enrichment culture, using the selective medium broth for 2 to 5 days, was performed and then, toxigenic C. difficile was confirmed by C. difficile toxin gene-specific PCR after being cultured on C. difficile selective agar. The sensitivity of C. difficile from the enrichment culture (100%) was higher than that of C. difficile selective agar culture (93.8%), while positive predictive values (PPV) were low; 72.7% (16/22) and 88.2% (15/17). PPV of the enrichment culture are not high. Recently, combinations of C. difficile selective agar culture, C. difficile A & B assays, glutamate dehydrogenase, and nucleic acid amplification method are widely used. The enrichment culture was disadvantageous in PPV, turn-around time, and cost. So, what we performed is not considered as a common method of diagnosis of C. difficile-associated diarrhea.