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1.
IEEE Trans Haptics ; 15(3): 626-637, 2022.
Article in English | MEDLINE | ID: mdl-35976838

ABSTRACT

A motion effect, the vestibular stimulus generated by a moving chair, is crucial in improving user experiences in many virtual reality (VR) and entertainment applications. However, the perceptual characteristics of motion effects remain unexplored to a great extent. This paper constructs a perceptual space that accounts for many motion effects based on their perceptual distances and then demonstrates smooth-rough and irregular-regular as its two primary perceptual dimensions. An authoring space is constructed with these two pairs as the axes. We also present methods for synthesizing new motion effects with a specific property in the authoring space. The contributions of this work are with new insights into the perceptual characteristics of motion effects and the first design methods of motion effects achieving desired perceptual properties.


Subject(s)
Virtual Reality , Humans , Motion
2.
Article in English | MEDLINE | ID: mdl-24299983

ABSTRACT

Herein, we reports synthesis, characterization and photocatalytic degradation of Rhodamine B under natural sunlight using zinc oxide and Ag-ZnO composite. Zinc oxide nanoparticles were prepared by simple wet chemical method using ethanol-water mixture. Ag-ZnO composite was prepared in two steps by dispersing synthesized ZnO in silver nitrate solution and subsequently reducing it with Ocimum tenuiflorum leaves extract as bioreducing agent. The synthesized bare zinc oxide and Ag-ZnO composite was characterized by various techniques like XRD, DRS, FE-SEM, TEM, SAED, PSD, Zeta potentials, etc. Zinc oxide being wide band gap material can absorbs UV light from solar spectrum which is only 5% so is not efficient material for dye degradation under sunlight. The absorption of visible light was increased by preparing the Ag-ZnO composite. The enhancement in photocatalytic activities of Ag-ZnO composite was observed than bare ZnO. This enhancement is due to shift of absorption edge of ZnO in visible region and decrease in band gap.


Subject(s)
Light , Metal Nanoparticles/chemistry , Silver/chemistry , Zinc Oxide/chemistry , Zinc Oxide/chemical synthesis , Absorption, Physicochemical , Catalysis/radiation effects , Rhodamines/chemistry , Scattering, Radiation , Temperature , Time Factors , X-Ray Diffraction
3.
Article in English | MEDLINE | ID: mdl-23353761

ABSTRACT

A simple and selective method is developed for the extraction spectrophotometric determination of ruthenium(III) using o-methylphenyl thiourea (OMPT) as a chromogenic chelating ligand. The basis of the proposed method is ruthenium(III)-OMPT complex formation in aqueous hydrochloric acid media (3.0molL(-1)) after 5.0min heating on a boiling water bath and the complex formed is extracted into chloroform. The absorbance of green colored ruthenium(III)-OMPT complex is measured at 590nm against the reagent blank. Beer's law was obeyed up to 42.5µgmL(-1) of ruthenium(III) and the optimum concentration range is 7.56-39.81µgmL(-1) of ruthenium(III) as evaluated by Ringbom's plot. Molar absorptivity and Sandell's sensitivity of ruthenium(III)-OMPT complex in chloroform are 2.34×10(3)Lmol(-1) cm(-1) and 0.043µgcm(-2) respectively. The composition of ruthenium(III):OMPT complex (1:2) was established from slope ratio method, mole ratio method and Job's continuous variation method. Complex was stable for more than 48h. The interfering effect of various foreign ions was studied and suitable masking agents are used wherever necessary to enhance the selectivity of the method. Proposed method is successfully applied for determination of ruthenium(III) from binary and ternary synthetic mixtures, synthetic mixtures corresponding to fissium alloy and ruthenium catalyst. Repetition of the method was checked by finding relative standard deviation (R.S.D) for 10 determinations which was 0.23%. A scheme for sequential separation of palladium(II), ruthenium(III), rhodium(III) and platinum(IV) has been developed.


Subject(s)
Chelating Agents/chemistry , Chemical Fractionation/methods , Ruthenium/analysis , Spectrophotometry/methods , Thiourea/analogs & derivatives , Alloys/chemistry , Catalysis , Ruthenium/isolation & purification , Sensitivity and Specificity , Solvents
4.
J Photochem Photobiol B ; 113: 63-9, 2012 Aug 01.
Article in English | MEDLINE | ID: mdl-22673014

ABSTRACT

Current study employs fluorescence spectroscopy, UV-Vis absorbance spectroscopy, dynamic light scattering (DLS) and cyclic voltammetry (CV) to investigate the interaction of safranine dye with spherical shaped silver nanoparticles (AgNPs) coated with trisodium citrate. In fluorescence spectroscopic study we used the AgNPs and safranine dye as component molecules for the construction of FRET, whereas AgNPs serve as donor fluorophore and safranine as acceptor. The fluorescence quenching of AgNPs followed by sensitization of safranine occurs almost simultaneously by addition of safranine dye with different concentrations, indicating fluorescence energy transfer observed between them. Interaction between safranine and AgNPs is also confirmed by using UV-Vis absorption spectroscopy. Addition of safranine results in the significant decrease in the absorbance of AgNPs at 423 nm and simultaneous increase in the absorbance of safranine at 518, 276 and 248 nm which is indication of rapid binding of safranine molecules with AgNPs. However CV measurements reveals that the safranine molecule does not alter the redox properties of the AgNPs but the safranine molecule lose their redox properties upon getting bonded with AgNPs. This clearly confirms that the safranine molecules get attached on the surface of AgNPs which was also supported by the DLS as well as zeta potential measurement.


Subject(s)
Citrates/chemistry , Fluorescence Resonance Energy Transfer , Metal Nanoparticles/chemistry , Phenazines/chemistry , Silver/chemistry , Colloids , Molecular Structure , Surface Properties , X-Ray Diffraction
5.
Se Pu ; 30(9): 931-7, 2012 Sep.
Article in English | MEDLINE | ID: mdl-23285976

ABSTRACT

A selective method has been developed for the extraction chromatography of aluminium (III) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (a liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium (III) was quantitatively extracted with the 0.065 mol/L N-n-octylaniline in 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min. The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration, the reagent concentration, the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient (Kd (Al (III))) versus N-n-octylaniline concentration in 0. 005 and 0. 007 mol/L sodium succinate gave the slopes of 0.5 and 0.7 respectively and showed the probable composition of the extracted species was 1:1 (metal to amine ratio) and the nature of extracted species was [RR'NH2(+), Al succinate2(-)]org. The extraction of aluminium(III) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(III) has been separated from multicomponent mixtures, pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium (III), indium (III), gallium (III) and thallium (III) has been developed by using suitable masking agents. The method is fast, accurate and precise.

6.
Spectrochim Acta A Mol Biomol Spectrosc ; 84(1): 117-24, 2011 Dec 15.
Article in English | MEDLINE | ID: mdl-21978559

ABSTRACT

A synergistic simple and selective spectrophotometric method was developed for the determination of cobalt(II) with 1-(2',4'-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydropyrimidine-2-thiol [2',4'-dinitro APTPT] as a chromogenic reagent. The proposed method has been described on the basis of synergistic effective extraction of cobalt(II) in presence of pyridine at pH range 9.5-10.2, showed orange-red coloured ternary complex having molar ratio 1:2:2 (M:L:Py). The equilibrium time is 10 min for extraction of cobalt(III) from organic phase. The absorbance of coloured organic layer in chloroform is measured spectrophotometrically at 490 nm against reagent blank. The Beer's law was obeyed in the concentration range 2.5-15 µg mL(-1) of cobalt(II) and optimum concentration range was 5-12.5 µg mL(-1) of cobalt(II) and it was evaluated from Ringbom's plot. The molar absorptivity and Sandell's sensitivity of cobalt(II)-2',4'-dinitro APTPT-pyridine complex in chloroform are 1.109×10(3) L mol(-1) cm(-1) and 0.053 µg cm(-2), respectively while molar absorptivity and Sandell's sensitivity of cobalt(II)-2',4'-dinitro APTPT complex in chloroform are 6.22×10(2) L mol(-1) cm(-1) and 0.096 µg cm(-2), respectively. The composition of cobalt(II)-2',4'-dinitro APTPT-pyridine complex (1:2:2) was established by slope ratio method, mole ratio method and Job's method of continuous variation. The ternary complex was stable for more than 48 h. The interfering effects of various cations and anions were also studied, and use of suitable masking agents enhances the selectivity of the method. The method is successfully applied for the determination of cobalt(II) in binary, synthetic mixtures and real samples. A repetition of the method was checked by finding relative standard deviation (R.S.D.) for n=5 which was 0.15%. The reliability of the method is confirmed by comparison of experimental results with atomic absorption spectrophotometer.


Subject(s)
Alloys/chemistry , Chelating Agents/chemistry , Chromogenic Compounds/chemistry , Cobalt/analysis , Nanocomposites/chemistry , Spectrophotometry/methods , Absorption , Aniline Compounds/chemistry , Color , Hydrogen-Ion Concentration , Ions , Ligands , Optical Phenomena , Pyridines/chemistry , Solvents/chemistry , Sulfhydryl Compounds/chemistry , Time Factors
7.
Talanta ; 81(3): 1088-95, 2010 May 15.
Article in English | MEDLINE | ID: mdl-20298898

ABSTRACT

Synergistic liquid-liquid extractive spectrophotometric determination of gold(III) using 1-(2',4'-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydro pyrimidine-2-thiol [2',4'-dinitro APTPT] has been described. Equal volumes (5cm(3)) of the 2',4'-dinitro APTPT (0.02molL(-1)) in the presence of pyridine (0.5molL(-1)) form an orange-red coloured ternary complex with gold(III) of molar ratio 1:1:1 at pH 1.8-2.4 with 5min of shaking. The absorbance of coloured organic layer in 1,2-dichloroethane is measured spectrophotometrically at 445nm against reagent blank. A pronounced synergism has been observed by the binary mixture of 2',4'-dinitro APTPT and pyridine, which shows that the enhancement in the absorbance is observed in the presence of pyridine by the adduct formation in the organic phase. Beer's law was obeyed in the concentration range 2.5-20.0microgmL(-1), with molar absorptivity and Sandell's sensitivity values of 8.7x10(3)dm(3)mol(-1)cm(-1) and 0.023microgcm(-2) respectively. A repetition of the method was checked by finding relative standard deviation (R.S.D.) (n=10) which was 0.17%. The composition of the gold(III)-2',4'-dinitro APTPT-pyridine adduct was established by slope analysis, molar ratio and Job's method. The ternary complex was stable for more than 48h. The influence of various factors such as pH, 2',4'-dinitro APTPT concentration, solvent and pyridine on the degree of complexation has been established. A number of foreign ions tested for their interferences and use of suitable masking agents wherever necessary are tabulated, which show that selectivity of the method has been enhanced. The method is successfully employed for the determination of gold(III) in binary, synthetic mixtures and ayurvedic samples. The reliability of the method is assured by inter-comparison of experimental values, using an atomic absorption spectrometer.


Subject(s)
Aniline Compounds/chemistry , Gold/chemistry , Spectrophotometry/methods , Sulfhydryl Compounds/chemistry , Absorption , Aniline Compounds/analysis , Chemistry Techniques, Analytical , Copper/chemistry , Hydrogen-Ion Concentration , Ligands , Models, Chemical , Nitrogen/chemistry , Organic Chemicals/chemistry , Solvents/chemistry , Sulfhydryl Compounds/analysis , Time Factors
8.
IEEE Trans Haptics ; 3(2): 138-149, 2010.
Article in English | MEDLINE | ID: mdl-27788120

ABSTRACT

As technology advances, more functions have been, and continue to be added to the vehicle, resulting in increased needs for improved user interfaces. In this paper, we investigate the feasibility of using vibrotactile feedback for in-vehicle information delivery. First, we measured the spectral characteristics of ambient vibrations in a vehicle, and designed clearly distinguishable sinusoidal vibrations. We further selected via dissimilarity rating the four sets of sinusoidal vibrations which had three to six vibrations. Second, we evaluated the learnability of the vibration sets when associated with common menu items of a Driver Information System (DIS). We also replaced the two most confused sinusoidal vibrations with patterned messages, and assessed the degree of learnability improvement. Finally, we evaluated the extent to which participants could select a desired function in a DIS via vibrotactile messages while simultaneously performing a driving-like primary task with higher priority. The results demonstrated high potential for vibrotactile messages to be effectively used for the communicative transfer of in-vehicle system information.

9.
Appl Ergon ; 35(3): 263-74, 2004 May.
Article in English | MEDLINE | ID: mdl-15145289

ABSTRACT

This research explores different ways to use features of one's own body for interacting with computers. Such "body-based" interfaces may find good uses in wearable computing or virtual reality systems as part of a 3D multi-modal interface in the future, freeing the user from holding interaction devices. Four types of body-based interfaces have been identified: Body-inspired metaphor (BIM); Body-as-interaction-surface (BAIS); Mixed mode (MM); and Object mapping (OM). These four body-based interfaces were applied to a few different applications (and associated tasks) and were tested for their performance and preference. It was generally found that, among the four, the BIM exhibited low error rates, but produced relatively longer task completion times and significant fatigue. The BAIS method had the contrasting character of higher error rates, but shorter task completion times and lower intuitiveness. The OM method exhibited high error rates, longer completion times, and much fatigue. Overall, the MM was superior in terms of both performance and preference as it combined the merits of the above three methods. Thus, it is expected, for applications with many associated tasks, a careful division of tasks among those that have natural semantic links to body parts and those that do not, is necessary to design the most performing body-based interface.


Subject(s)
Man-Machine Systems , Computer Simulation , Humans , Korea , User-Computer Interface
10.
Ergonomics ; 46(13-14): 1441-61, 2003.
Article in English | MEDLINE | ID: mdl-14612330

ABSTRACT

A fundamental assumption in this paper is that user satisfaction depends on product design. The approach consists of 5 steps: (1) define user satisfaction, (2) decompose product design elements, (3) conduct experiments, (4) develop relationship models, and (5) analyse critical design features. In order to demonstrate the practicability of this approach, relationship models were developed based on experimental data using a total of 60 subjects (30 American and 30 Korean subjects). In addition, critical design features and their common properties were identified for audio/visual consumer products. Similarities and differences between American and Korean consumers were discussed. The resulting relationship models can be used to predict user satisfaction and provide significant remedies for design change.


Subject(s)
Consumer Behavior/statistics & numerical data , Man-Machine Systems , Models, Theoretical , Adult , Data Display , Equipment Design/psychology , Ergonomics/psychology , Humans , Korea , Linear Models , United States , User-Computer Interface
11.
Appl Ergon ; 33(5): 419-31, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12236651

ABSTRACT

Usability evaluation is now considered an essential procedure in consumer product development. Many studies have been conducted to develop various techniques and methods of usability evaluation hoping to help the evaluators choose appropriate methods. However, planning and conducting usability evaluation requires considerations of a number of factors surrounding the evaluation process including the product, user, activity, and environmental characteristics. In this perspective, this study suggested a new methodology of usability evaluation through a simple, structured framework. The framework was outlined by three major components: the interface features of a product as design variables, the evaluation context consisting of user, product, activity, and environment as context variables, and the usability measures as dependent variables. Based on this framework, this study established methods to specify the product interface features, to define evaluation context, and to measure usability. The effectiveness of this methodology was demonstrated through case studies in which the usability of audiovisual products was evaluated by using the methods developed in this study. This study is expected to help the usability practitioners in consumer electronics industry in various ways. Most directly, it supports the evaluators' plan and conduct usability evaluation sessions in a systematic and structured manner. In addition, it can be applied to other categories of consumer products (such as appliances, automobiles, communication devices, etc.) with minor modifications as necessary.


Subject(s)
Audiovisual Aids/standards , Commerce , Consumer Behavior , Electronics/instrumentation , Ergonomics , Equipment Design , Evaluation Studies as Topic , Humans , Korea , Product Line Management/methods , Task Performance and Analysis
12.
Int J Occup Saf Ergon ; 8(3): 387-406, 2002.
Article in English | MEDLINE | ID: mdl-12189109

ABSTRACT

A systematic modeling approach to describing, prescribing, and predicting usability of a product has been presented. Given the evaluation results of the usability dimension (UD) and the measurement of the product's design variables, referred to as the human interface elements (HIEs), the approach enables one to systematically assess the relationship between the UD and HIEs. The assessed relationship is called a usability model. Once built, such a usability model can relate, in a quantitative manner, the HIEs directly to the UDs, and thus can serve as an effective aid to designers by evaluating and predicting the usability of an existing or hypothetical product. A usability model for elegance of audiovisual consumer electronic products has been demonstrated.


Subject(s)
Audiovisual Aids , Electronics , Man-Machine Systems , Equipment Design , Humans , Models, Theoretical
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