• Journal of the Korean institute of surface engineering
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• v.39 no.3
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• pp.137-141
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• 2006

Process window for infinite etch selectivity of silicon nitride $(Si_3N_4)$ layers to ArF photoresist (PR) was investigated in dual frequency superimposed capacitive coupled plasma (DFS-CCP) by varying the process parameters such as low frequency power $(P_{LF})$, $CH_2F_2$ and $H_2$ flow rate in $CH_2F_2/H_2/Ar$ plasma. It was found that infinite etch selectivities of $Si_3N_4$ layers to the ArF PR on both blanket and patterned wafers can be obtained for certain gas flow conditions. The etch selectivity was increased to the infinite values as the $CH_2F_2$ flow rate increases, while it was decreased from the infinite etch selectivity as the $H_2$ flow rate increased. The preferential chemical reaction of the hydrogen with the carbon in the polymer film and the nitrogen on the $Si_3N_4$ surface leading to the formation of HCN etch by-products results in a thinner steady-state polymer and, in turn, to continuous $Si_3N_4$ etching, due to enhanced $SiF_4$ formation, while the polymer was deposited on the ArF photoresist surface.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.8
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• pp.311-317
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• 2016

Many services have been developed that are based on smart devices, and security between devices is emphasized. A beacon on the current IoT(Internet of Things) services has been utilized in the commercial field and is being applied to the services of the home IoT. On the other hand, the beacon is weak to security using Bluetooth-based services. Therefore, it is important to strengthen the security of the beacon. This paper proposes a dual security technique that can enhance the security of beacon-based services. The dual security architecture and security process is proposed based on beacon and authentication service. In addition, mobile application was developed and validated based on the beacon for proving the suitability of the proposed technique. The experimental method for verification are the authentication failure case, such as 1st authentication fail, and authentication success case, such as 1st authentication success and 2nd authentication success. The components of the verification experiments consists of two beacons (matched with Beacon ID, mismatched with Beacon ID), one mobile device and authentication application. This was tested to verify the compatibility of the dual security architecture and 1st/2nd authentication process.

• Journal of Digital Convergence
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• v.19 no.1
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• pp.99-105
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• 2021

This study aimed to verify the positive effect of work meaningfulness(WM) on flourishing(FL) with the successive positive effects of work engagement(WE) and job performance(JP) as dual mediators. We conducted an online survey of 395 incumbents working in the companies of different types and statistically analyzed data using SPSS and SPSS Process macro for hierarchical regression and bootstrapping. The results are as follows: 1. correlation coefficients of all combinations from four variables are significant, 2. simple mediation effects(WM-WE-FL and WE-JP-FL) are significant, 3. dual mediation effet(WM-WE-JP-FL) is verified. This study showed practical guide for the efficient management of employees in recent autonomous work environment and further studies with longitudinal method will be needed in order to verify substantially the dual mediation.

• Journal of applied mathematics & informatics
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• v.34 no.1_2
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• pp.167-178
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• 2016

In this paper, we study the stochastic integral of processes taking values of generalized operators based on a triple E ⊂ H ⊂ E^∗, where H is a Hilbert space, E is a countable Hilbert space and E^∗ is the strong dual space of E. For our purpose, we study E-valued Wiener processes and then introduce the stochastic integral of L(E, F^∗)-valued process with respect to an E-valued Wiener process, where F^∗ is the strong dual space of another countable Hilbert space F.

• Journal of Welding and Joining
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• v.31 no.4
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• pp.23-27
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• 2013

Laser heat source was used for automotive interior and exterior parts to reduce weights. Typically, 900's nm wavelength of laser has been widely used for polymer joining, however, the transmittance of the laser beam thorough clear polymers such as PMMA or PC has been an issue to overcome. To solve this issue, 1,940nm laser was applied on the clear polymer for the better absorption and 900nm laser beam was used for main laser for the joining. Conventional Gaussian or Elliptical heat source approximation has limitation in polymer which had deeper skin depth where major laser beam absorbs. To accurately simulate the physical laser beam absorption and joining optical properties were experimentally measured for the computer FEM simulation. The simulation results showed close correlation between theoretical and experimental results. The developed laser process is expected to increase productivity and gap closing which can cause failure of joining in laser material processing.

• Asia Marketing Journal
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• v.23 no.1
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• pp.5-27
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• 2021

This paper seeks to suggest user satisfaction model of digital signage to see how new in-store technology can effectively lead to customers' shopping satisfaction in fashion retails. Authors in particular focus on technological complexity, which is expected to serve a subtle role in using digital signage. This study employed a scenario-based online survey. Interactive digital signage with virtual try-on and video-captures functions was used as stimuli. Data were collected from 320 respondents and 307 useable responses were analyzed to examine a proposed model. Research model compares dual paths of motivators: the extrinsic motivation route that leads from usefulness to shopping outcome satisfaction and intrinsic motivation route that leads from enjoyment to shopping process satisfaction. Technological complexity of digital signage indirectly and negatively influences shopping outcome and process satisfaction, mediated by usefulness and enjoyment, but directly and positively affects shopping process satisfaction. In omni-channel environments, the findings have implications for fashion retail managers in using digital signage to maximize customer satisfaction and to counterbalance the advantages and disadvantages of technological complexity.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.11
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• pp.681-684
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• 2016

This research was carried out experiments of variety IGBTs for industrial inverter and electric vehicle. The devices for this paper were planar gate IGBT, trench gate IGBT and dual gate IGBT and we designed using same design and process parameters. As a result of experiments, the electrical characteristics of planar gate IGBT were 1,459 V of breakdown voltage, 4.04 V of threshold voltage and 4.7 V of on-state voltage drop. And the electrical characteristics of trench gate IGBT were 1,473 V of breakdown voltage, 4.11 V of threshold voltage and 3.17 V of on-state voltage drop. Lastly, the electrical characteristics of dual gate IGBT were 1,467 V of breakdown voltage, 4.14 V of threshold voltage and 3.08V of on-state voltage drop. We almost knew that the trench gate IGBT was superior to dual gate IGBT in terms of breakdown voltage. On the other hand, the dual gate IGBT was better than the trench gate IGBT in terms of on state voltage drop.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.3 s.246
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• pp.334-341
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• 2006

A solid freeform fabrication (SFF) system using selective laser sintering (SLS) is currently recognized as a leading process and the SLS extends the applications to machinery and automobiles due to various employing materials. In order to fabricate a large part with SFF system, dual laser approach has been introduced. Since the building room is divided into two regions, each scan path for dual laser system is generated based on the single laser scan path. Scan paths for each laser have to be synchronized and consider mechanical strength against fracture at the interfaced region. This paper will address generation of single laser scan path which deals with special cases for unnecessary scan points and generation of dual laser scan path according to various divided regions to enhance mechanical strength. To evaluate the developed scan path method, the specimen will be fabricated and evaluated.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.8 no.4
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• pp.1276-1291
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• 2014

In the field of visible light communication (VLC), light-emitting diodes (LEDs) are used for transmitting data via visible light. In this study, we analyze pulse dual slope modulation (PDSM) as a means of delivering information in VLC. PDSM involves the modulation of symmetrical slope pulses to encode binary 0s and 1s, and owing to the moderately increasing and decreasing pulse shapes that are created, this method enables more spectral efficiency than the variable pulse position modulation (VPPM) technique currently adopted in IEEE 802.15.7. In particular, PDSM allows for the avoidance of intra-frame flicker by providing idle pulses in a spectrum-efficient way. A simple detection scheme is proposed for PDSMsignals, and its bit error rate (BER) is analyzed mathematically at varying slopes to validate the process through simulation. The BER performance of PDSM detection using dual sampling is compared to the performances of PDSM and VPPM using correlation detection. It is found that, when the probability of idle pulse transmission is less than 0.08 and higher than 0, the BER of dual sampling PDSM is lower than that of PDSM using correlation detection over the entire light intensity range.

• Journal of Sensor Science and Technology
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• v.26 no.4
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• pp.223-227
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• 2017

Conventional CMOS image sensors (CISs) have a trade-off relationship between dynamic range and sensitivity. In addition, their sensitivity is determined by the photodiode capacitance. In this paper, CISs that consist of dual-sensitivity photodiodes in a unit pixel are proposed for achieving wide dynamic ranges. In the proposed CIS, signal charges are generated in the dual photodiodes during integration, and these generated signal charges are accumulated in the floating-diffusion node. The signal charges generated in the high-sensitivity photodiodes are transferred to the input of the comparator through an additional source follower, and the signal voltages converted by the source follower are compared with a reference voltage in the comparator. The output voltage of the comparator determines which photodiode is selected. Therefore, the proposed CIS composed of dual-sensitivity photodiodes extends the dynamic range according to the intensity of light. A $94{\times}150$ pixel array image sensor was designed using a conventional $0.18{\mu}m$ CMOS process and its performance was simulated.