Search results for: Sangjun Park

Items from 1 to 20 out of 52 results

article

A Systematic Study of Spin‐Dependent Recombination in GaAs_1−xN_x as a Function of Nitrogen Content

Agatha C. Ulibarri, Rishabh Kothari, Alejandro Garcia, Jean-Christophe Harmand, more

physica status solidi (b) > 260 > 5 > n/a - n/a

A systematic study of spin‐dependent recombination (SDR) under steady‐state optical pumping conditions as a function of nitrogen content, x, in dilute nitride alloys of the form GaAs_1−xN_x is reported. Use of high‐excitation power densities up to 10⁷ W cm⁻² allows measurement of the full SDR versus power curves, even at relatively high nitrogen contents of x = 0.039. Alloy contents for

0.022 \leq x \leq 0.039

...

article

Accelerated FRET-PAINT microscopy

Jongjin Lee, Sangjun Park, Sungchul Hohng

Molecular Brain > 2018 > 11 > 1 > 1-7

Recent development of FRET-PAINT microscopy significantly improved the imaging speed of DNA-PAINT, the previously reported super-resolution fluorescence microscopy with no photobleaching problem. Here we try to achieve the ultimate speed limit of FRET-PAINT by optimizing the camera speed, dissociation rate of DNA probes, and bleed-through of the donor signal to the acceptor channel, and further increase...

article

CMUT-based resonant gas sensor array for VOC detection with low operating voltage

Sangjun Park, Inug Yoon, Sungwoo Lee, Hyojung Kim, more

Sensors and Actuators B: Chemical > 2018 > 273 > C > 1556-1563

With the anticipation for a more connected world through the Internet of Things, there is still a strong demand for miniaturized chemical sensors. Here, we report on a miniaturized resonant chemical sensor based on a Capacitive Micromachined Ultrasonic Transducer (CMUT) with a low operating voltage suitable for portable gas sensor applications. Previously reported CMUT chemical sensors required a...

article

Superresolution fluorescence microscopy for 3D reconstruction of thick samples

Sangjun Park, Wooyoung Kang, Yeong-Dae Kwon, Jaehoon Shim, more

Molecular Brain > 2018 > 11 > 1 > 1-9

Three-dimensional (3D) reconstruction of thick samples using superresolution fluorescence microscopy remains challenging due to high level of background noise and fast photobleaching of fluorescence probes. We develop superresolution fluorescence microscopy that can reconstruct 3D structures of thick samples with both high localization accuracy and no photobleaching problem. The background noise is...

article

Accelerated super-resolution imaging with FRET-PAINT

Jongjin Lee, Sangjun Park, Wooyoung Kang, Sungchul Hohng

Molecular Brain > 2017 > 10 > 1 > 1-9

Super-resolution fluorescence microscopy in the current form is hard to be used to image the neural connectivity of thick tissue samples due to problems such as slow imaging speed, severe photobleaching of fluorescent probes, and high background noise. Recently developed DNA-PAINT solved the photobleaching problem, but its imaging speed is extremely low. We report accelerated super-resolution fluorescence...

article

Evolutionary Channel Sharing Algorithm for Heterogeneous Unlicensed Networks

M. A. Raza, Sangjun Park, Heung-No Lee

IEEE Transactions on Wireless Communications > 2017 > 16 > 7 > 4378 - 4389

Channel sharing in TV whitespace (TVWS) is challenging because of signal propagation characteristics and diversity in network technologies employed by secondary networks coexisting in TVWS. In this paper, the TVWS sharing problem is modeled as a multiobjective optimization problem, where each objective function tackles an important coexisting requirement, such as interference and disparity in network...

article

Numerical study of the performance and NOx emission of a diesel-methanol dual-fuel engine using multi-objective Pareto optimization

Sangjun Park, Jungkeun Cho, Jungsoo Park, Soonho Song

Energy > 2017 > 124 > C > 272-283

The effect of methanol addition on the performance and NO_x emission of a diesel engine was investigated using one-dimensional engine cycle simulation. The methanol component was injected into the intake manifold of a diesel engine at a certain energy fraction (0, 5, 10, or 15%) of the fuel. The in-cylinder pressure and temperature decreased as the methanol content increased due to the lower cetane...

article

Model-based multi-objective Pareto optimization of the BSFC and NOx emission of a dual-fuel engine using a variable valve strategy

Sangjun Park, Soonho Song

Journal of Natural Gas Science and Engineering > 2017 > 39 > C > 161-172

Various advanced technologies, including dual-fuel combustion, have been developed to meet reinforced emission regulations in the automobile industry. In this work, natural gas (NG) was added from 0 to 30% in steps of 10% as the energy fraction of the fuel to evaluate the fundamental effects of the NG substitution ratio (NSR) on the combustion, performance and nitrogen oxides (NO_x) emission of a dual-fuel...

article

An Information-Theoretic Study for Joint Sparsity Pattern Recovery With Different Sensing Matrices

Sangjun Park, Nam Yul Yu, Heung-No Lee

IEEE Transactions on Information Theory > 2017 > 63 > 9 > 5559 - 5571

In this paper, we study a support set reconstruction problem for multiple measurement vectors (MMV) with different sensing matrices, where the signals of interest are assumed to be jointly sparse and each signal is sampled by its own sensing matrix in the presence of noise. Using mathematical tools, we develop upper and lower bounds of the failure probability of the support set reconstruction in terms...

article

Drying shrinkage cracking of concrete using dune sand and crushed sand

Euibae Lee, Sangjun Park, Yongjic Kim

Construction and Building Materials > 2016 > 126 > C > 517-526

In this study, experimental results are presented to evaluate the properties of drying shrinkage cracking of concrete using dune sand (DS) and crushed sand (CS) as fine aggregate (FA). Concrete mixtures were made to meet the target workability with the variation of DS to FA ratio (DS/FA ratio) and water content.The results showed that the highest compressive strength and the highest tensile strength...

article

Transient Diagnosis and Prognosis for Secondary System in Nuclear Power Plants

Sangjun Park, Jinkyun Park, Gyunyoung Heo

Nuclear Engineering and Technology > 2016 > 48 > 5 > 1184-1191

This paper introduces the development of a transient monitoring system to detect the early stage of a transient, to identify the type of the transient scenario, and to inform an operator with the remaining time to turbine trip when there is no operator's relevant control. This study focused on the transients originating from a secondary system in nuclear power plants (NPPs), because the secondary...

article

Dual-Microphone Noise Reduction in Car Environments With Determinant Analysis of Input Correlation Matrix

Jungpyo Hong, Sangjun Park, Sangbae Jeong, Minsoo Hahn

IEEE Sensors Journal > 2016 > 16 > 9 > 3131 - 3140

In this paper, a novel noise reduction technique is proposed to improve the speech interface performance in car environments. The proposed noise reduction method with dual microphones is primarily based on the determinant analysis of the input correlation matrix. Through the analysis, a robust feature for speech activity detection and signal-to-noise ratio (SNR) estimation is derived. Using the feature,...

chapter

Reliability Evaluation for an Oxygen Generator in an Air-conditioner by Accelerated Life Testing

Yuri Jo, Sangjun Park, Seongsoo Lee, Sangdeuk Park

Probabilistic Safety Assessment and Management > Manufacturing — Process Control > 3054-3059

The oxygen generators in air-conditioners separate oxygen gas from air under high pressure by PSA (Pressure Swing Adsorption) method. The equipment was newly developed and there were not enough reliability test methods for it. Since we had to bring the product into market timely, we applied accelerated life tests by which we could detect weak points and obtain life and failure rate data in a short...

article

State-of-the-art automobile emissions models and applications in North America and Europe for sustainable transportation

Sangjun Park, Jung-beom Lee, Chungwon Lee

KSCE Journal of Civil Engineering > 2016 > 20 > 3 > 1053-1065

This paper presents a review of the state-of-the-art automobile emissions models that have been utilized in North America and Europe. The emissions models are classified into two categories: models for emissions inventory and instantaneous emissions models. Each model is explained in some detail, covering revisions and characteristics such as emissions modeling, user input, emissions processes, vehicle...

chapter

Sound event classification with feature vector combination for automatic audio-based surveillance

Seunghyung Lee, Jinuk Park, Sangjun Park, Minsoo Hahn

2016 IEEE International Conference on Consumer Electronics (ICCE) > 147 - 148

2016 IEEE International Conference on Consumer Electronics (ICCE)

This paper deals with the sound event classification for automatic audio-based surveillance. To improve the performance, we proposed a feature vector combination scheme to use multiple feature vectors simultaneously. Then, the performance is evaluated by using the combination of three segment-based features. The result shows significant amount of improvement compare to the conventional method.

chapter

Cluster-based voice activity detection for mobile devices

Sangjun Park, Seunghyung Lee, Jinuk Park, Minsoo Hahn

2016 IEEE International Conference on Consumer Electronics (ICCE) > 149 - 150

2016 IEEE International Conference on Consumer Electronics (ICCE)

A voice activity detection in mobile environments is not performed well due to arbitrary noises. In this paper, a robust voice activity detection framework for mobile devices is proposed. The unsupervised clustering and discriminative weight training of each cluster is employed to model various characteristics of arbitrary noises.

chapter

Accurate remaining range estimation for Electric vehicles

Joonki Hong, Sangjun Park, Naehyuck Chang

2016 21st Asia and South Pacific Design Automation Conference (ASP-DAC) > 781 - 786

2016 21st Asia and South Pacific Design Automation Conference (ASP-DAC)

EVs (Electric vehicle) generally have only around 22% driving ranges compared with ICEVs (Internal combustion engine vehicle) with a similar price range. Running out of the EV battery SoC (State of charge) while driving gives the same inconvenience as a vehicle breakdown. In this paper, we emphasize that an accurate remaining range estimation can efficiently mitigate the range anxiety of EV drivers...

article

Poster 176 Relationships between Chronic Low Back Pain and Sarcopenia in the Elderly

Sangjun Park, Hyun Bang, Chaiyoung Lim, master, Se Woong Chun, more

PM&R > 2015 > 7 > 9 Supplement > S149-S150

chapter

A study on bicycle crash risk based on GPS trajectories collected from bidirectional traffic

Dongwook Lee, Sangjun Park, Minsoo Hahn

2014 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS) > 383 - 386

2014 IEEE Asia Pacific Conference on Circuits and Systems (APCCAS)

As the number of bicyclists grows steadily, bicycle related crashes are getting more concerns. In order to enhance bicycle safety, various factors affecting bicycle crash risk have been investigated. This study attempts to extract the kinematic and the spatial features from a large number of the bicycle trajectories and to investigate their significance as the crash risk factors. The trajectories...

chapter

Web Based Visualization for Sports Data Pattern

Dongwook Lee, Minsoo Hahn, Sangjun Park, Seunghyung Lee

2014 International Conference on IT Convergence and Security (ICITCS) > 1 - 2

2014 International Conference on IT Convergence and Security (ICITCS)

In this paper, we present a method that aims to help the user's understanding on the sports data patterns. The proposed method extracts the node and link information from the sports data feed files and visualizes them using the force-directed graph in 2D space. The node and link information consists of the keywords obtained from the sports data feed. Olympic data feed files collected from several...

Publication date

Last 3 years (1)

Close

Date range setting

Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.

From:

To:
Set your own date range

Publication type

book (27)
article (25)

INFONA - science communication portal

Search results for: Sangjun Park

A Systematic Study of Spin‐Dependent Recombination in GaAs_1−xN_x as a Function of Nitrogen Content

Accelerated FRET-PAINT microscopy

CMUT-based resonant gas sensor array for VOC detection with low operating voltage

Superresolution fluorescence microscopy for 3D reconstruction of thick samples

Accelerated super-resolution imaging with FRET-PAINT

Evolutionary Channel Sharing Algorithm for Heterogeneous Unlicensed Networks

Numerical study of the performance and NOx emission of a diesel-methanol dual-fuel engine using multi-objective Pareto optimization

Model-based multi-objective Pareto optimization of the BSFC and NOx emission of a dual-fuel engine using a variable valve strategy

An Information-Theoretic Study for Joint Sparsity Pattern Recovery With Different Sensing Matrices

Drying shrinkage cracking of concrete using dune sand and crushed sand

Transient Diagnosis and Prognosis for Secondary System in Nuclear Power Plants

Dual-Microphone Noise Reduction in Car Environments With Determinant Analysis of Input Correlation Matrix

Reliability Evaluation for an Oxygen Generator in an Air-conditioner by Accelerated Life Testing

State-of-the-art automobile emissions models and applications in North America and Europe for sustainable transportation

Sound event classification with feature vector combination for automatic audio-based surveillance

Cluster-based voice activity detection for mobile devices

Accurate remaining range estimation for Electric vehicles

Poster 176 Relationships between Chronic Low Back Pain and Sarcopenia in the Elderly

A study on bicycle crash risk based on GPS trajectories collected from bidirectional traffic

Web Based Visualization for Sports Data Pattern

Filter options

Publication date

Publication type

Keywords

Data set

Journal

INFONA - science communication portal

Search results for: Sangjun Park

Add recipient

Sending message cancelled

Are you sure you want to cancel sending this message?

Send message

Filter options

Publication date

Date range setting

Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.

Publication type

Keywords

Data set

Journal

Reporting an error / abuse

Sending the report failed

Accessibility options