Widya Mandala Surabaya Catholic University

Surabaya, Indonesia
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Susanti C.E.,Widya Mandala Surabaya Catholic University
Advanced Science Letters | Year: 2017

CBR model is an approach to problem-based learning solution in a case study. CBR Model learners hone not only to identify problems but to know and understand the main source is the cause for the emergence of these problems so as to provide appropriate solutions as the strategic decisions and actions. This ability is important to have the students remember the students prepared by educational institutions in order to become a superior human being. © 2017 American Scientific Publishers All rights reserved.

Noviani E.P.F.,Widya Mandala Surabaya Catholic University
AIP Conference Proceedings | Year: 2017

As a consequence of quantum confinement effect, the band gaps of nanowires are usually larger than its bulk counterpart. In this research, we study the electronic structures of [111]-oriented tin nanowires (Sn NWs) passivated with hydrogen atoms using density functional theory. Bulk Sn is known as a semimetal material with zero band gap, however the band gap is opened when tin nanowire is constructed e.g. the band gap of SnNW with diameter about 1.4 nm is 1.54 eV. The electronic structure of [111]-oriented SnNW under strain is also investigated. In the absence of strain, SnNWs have direct band gap, however under strain, direct-to-indirect band gap transition is observed. The critical strain for direct-to-indirect band gap transition is varied for various diameter of SnNWs. It is found that both tensile and compressive strain reduces the band gap. © 2017 Author(s).

Shanti,Widya Mandala Surabaya Catholic University
Advanced Science Letters | Year: 2017

“Money earned through gifts without efforts will be spent more quickly than the money resulted from efforts or works (easy come, easy go).” Human behavior related to money cannot be separated from mental accounting contained inside that person. Mental accounting frequently makes the human behavior become irrational and incompatible with the existing economic theory such as expected utility theory and fungible theory. Mental accounting is the human way of thinking, assumed that in the human brain there are barriers that would separate the events related to the money into the accounts of income, spending, and saving. The way of thinking in this decision making is certainly influenced also by background knowledge and life-story obtained by humans during their lifetime. Accountant knowledge about accounting is surely different from persons who have never known or studied accounting at all (non-accountants). This study aims to observe the mental accounting of consumers, particularly the mental accounting between consumers with accounting educational background (accountants) and non-accounting educational background (non-accountants), which affects the behavior of decision making under conditions that there are discount coupons in online shops. This was a survey quantitative research with the samples of online shop customers redeeming the discount coupons by random sampling based on Computerized Grocery-Shopping Simulation. The test results using Linear Regression Test and Different Test in SPSS 21 state that the accounting education should revolutionize and renovate the accounting mental of accountants, so it can be more helpful in rational decision making than the non-accountants. © 2017 American Scientific Publishers All rights reserved.

The strategic role of branding in corporate competitive advantage is already proven, especially in service industry. In contact with many consumers, employee has the central function to deliver good quality of service. This marketing terms is known by the Employee-Based Brand Equity (EBBE). The research model was design to analyze not only focus on the internal brand building behavior process management, but also conducted to the other facets on brand citizenship behavior and behavioral branding for organizational competitive advantages. The source of data interviewed via a field survey of 330 employees that work in bank as service organizations, sourced from a market research Bank Indonesia data base list. A serial analysis methods of SEM, was conducted to several model test, and also used LISRELL software for good statistically validation test. Good result test was found for 27 of the hypothesis relationships confirmed validation for the proposed model. © 2017 American Scientific Publishers All rights reserved.

Soetaredjo F.E.,Widya Mandala Surabaya Catholic University | Ayucitra A.,Widya Mandala Surabaya Catholic University | Ismadji S.,Widya Mandala Surabaya Catholic University | Maukar A.L.,Widya Mandala Surabaya Catholic University
Applied Clay Science | Year: 2011

A potential application of KOH/bentonite as a catalyst for biodiesel production was studied. A series of KOH/bentonite catalysts was prepared by impregnation of bentonite from Pacitan with potassium hydroxide. The ratios between KOH and bentonite were 1:20, 1:10, 1:5, 1:4, 1:3, and 1:2. The characterization of KOH/bentonite and natural bentonite was conducted by nitrogen adsorption and XRD analysis. The effects of various reaction variables on the yield of biodiesel were investigated. The highest yield of biodiesel over KOH/bentonite catalyst was 90.70 ± 2.47%. It was obtained at KOH/bentonite 1:4, reaction time of 3. h, 3% catalyst, methanol to oil ratio of 6, and the reaction temperature at 60 °C. © 2010 Elsevier B.V.

Ismanto A.E.,Widya Mandala Surabaya Catholic University | Wang S.,Widya Mandala Surabaya Catholic University | Soetaredjo F.E.,Widya Mandala Surabaya Catholic University | Ismadji S.,Widya Mandala Surabaya Catholic University
Bioresource Technology | Year: 2010

Cassava peel was used as the precursor for activated carbon-based electrodes which were then prepared by a combination of chemical and physical activation. The surface of the activated carbon was treated with the oxidative chemical agents, 98 wt.% H 2SO 4, 65 wt.% HNO 3, and 30 wt.% H 2O 2 solutions. The surface modification had no significant effect on the specific surface area, but greatly influenced the surface chemistry of the carbons. The presence of oxygen-containing groups increased the polarity and hydrophilicity of activated carbon, and thus improved the performance of the activated carbon-based electrode. As a result, the specific capacitance of the HNO 3 modified AC-electrode reached 264.08 F/g, an increase of 72.6% compared to the original one. The results indicate that cassava peel waste can potentially be applied as a raw material for the production of low cost-high performance activated carbon electrode materials for Electric Double Layer Capacitors (EDLCs). © 2010 Elsevier Ltd. All rights reserved.

Suryaputra W.,Widya Mandala Surabaya Catholic University | Winata I.,Widya Mandala Surabaya Catholic University | Indraswati N.,Widya Mandala Surabaya Catholic University | Ismadji S.,Widya Mandala Surabaya Catholic University
Renewable Energy | Year: 2013

The waste Capiz shell was utilized as raw material for catalyst production for biodiesel preparation. During calcination process, the calcium carbonate content in the waste capiz shell was converted to CaO. This calcium oxide was used as catalyst for transesterification reaction between palm oil and methanol to produce biodiesel. The biodiesel preparation was conducted under the following conditions: the mole ration between methanol and palm oil was 8:1, stirring speed was 700 rpm, and reaction temperature was 60 °C for 4, 5, and 6 h reaction time. The amount of catalyst was varied at 1, 2, 3, 4, and 5 wt %. The maximum yield of biodiesel was 93 ± 2.2%, obtained at 6 h of reaction time and 3 wt % of amount of catalyst. In order to examine the reusability of catalyst developed from waste of capiz (Amusium cristatum) shell, three transesterification reaction cycles were also performed. © 2012 Elsevier Ltd.

Prahas D.,National Taiwan University of Science and Technology | Liu J.C.,National Taiwan University of Science and Technology | Ismadji S.,Widya Mandala Surabaya Catholic University | Wang M.-J.,National Taiwan University of Science and Technology
Journal of Environmental Engineering (United States) | Year: 2012

Tetramethylammonium hydroxide (TMAH) is widely used in manufacturing thin-film transistor liquid crystal displays (TFT-LCD) and semiconductors. Because of its toxicity and nitrogen content, TMAH-containing wastewater has to be properly treated before discharge. In this study, several commercial activated carbons were characterized and used for TMAH adsorption. Activated carbon with micropores showed higher adsorption capacity for TMAH. The adsorption kinetics could be represented by pseudo-second-order model, and the Langmuir model fitted the adsorption of TMAH on activated carbon under different pH adsorption well. Higher pH was favorable for TMAH adsorption, while there was no TMAH adsorption at pH 4.7±0.2. The adsorption was spontaneous and exothermic. Exhausted carbon could be easily regenerated by 0.1 N HCl, with no considerable reduction in performance even after five cycles of adsorption-desorption. It was proposed that electrostatic interaction was the main mechanism of TMAH adsorption on the activated carbon. © 2012 American Society of Civil Engineers.

Sari Dewi D.R.,Widya Mandala Surabaya Catholic University
ARPN Journal of Engineering and Applied Sciences | Year: 2016

QFD is a methodology that helps translating customer desires into technical specifications. Rating assessment in determining the relationship between customer need and engineering characteristics are often very subjective in QFD. QFD also assume that customer satisfaction is determined linearly with the need of customers. Yet according to the model of Kano, the increase in customer satisfaction is not linear with the need of customers. This study contributes to application the mathematical modeling to maximize customer need simultaneously in minimizing customer dissatisfaction to assign product development resources. The relationship between consumer desire and technical characteristics were obtained by regression. The model was applied to cabinet design. Results showed that the output obtained by the model can assign existing resources to improve customer satisfaction and dissatisfaction. © 2006-2016 Asian Research Publishing Network (ARPN).

Kurniawan A.,Widya Mandala Surabaya Catholic University | Ismadji S.,Widya Mandala Surabaya Catholic University
Journal of the Taiwan Institute of Chemical Engineers | Year: 2011

Low cost activated carbon was prepared from the press-cake residue of Jatropha curcas L. The effectiveness of this activated carbon and its modified forms (chemical and thermal activation) was evaluated for methylene blue (MB) dye removal from aqueous solution. Adsorption experiments were conducted in batch system at various pH and temperatures. The widely used isotherm models, Langmuir and Freundlich, were employed to represent equilibrium data. Kinetic data were analyzed using pseudo-first order and pseudo-second order model. Thermodynamic properties (ΔG0, ΔH0 and ΔS0) of the adsorption of methylene blue onto Jatropha carbons were also obtained. The thermal activated carbon (JAC-3) was more effective for MB dye removal compared to chemical (JAC-2) and parent (JAC-1) activated carbon. © 2011 Taiwan Institute of Chemical Engineers.

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