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Sanghyun Lee

Bio: Sanghyun Lee is an academic researcher from Samsung. The author has contributed to research in topics: Distributed algorithm & Aldose reductase. The author has an hindex of 29, co-authored 295 publications receiving 3208 citations. Previous affiliations of Sanghyun Lee include University of Texas at Austin & Electronics and Telecommunications Research Institute.


Papers
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Patent
25 Nov 2003
TL;DR: In this paper, an adaptive transmit and receive method and device in a multiple-antenna wireless communication system is described, where a transmitter calculates an STBC performance parameter and a SM performance parameter, and uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption.
Abstract: Disclosed is an adaptive transmit and receive method and device in a multiple-antenna wireless communication system A transmit mode comprises different main transmit modes each of which includes one or both of a sub-transmit mode based on STBC and a sub-transmit mode based on SM A receiver calculates an STBC performance parameter and a SM performance parameter, and a transmitter uses the parameters to determine a main transmit mode with maximum data rates and select a sub-transmit mode for minimizing power consumption The transmitter channel-encodes, modulates and antenna-maps input data according to the selected transmit mode, and outputs results to the receiver The receiver antenna/symbol-demodulates and channel-decodes the received data

107 citations

Journal ArticleDOI
TL;DR: Geniposide showed anti-angiogenic activity in a dose-dependent manner and exhibited an inhibitory effect in the range of 25-100 microM on the growth of the transformed NIH3T3 cell line.
Abstract: The EtOH extract of gardenia (Gardenia jasminoides Ellis) fruits was previously found to possess potent anti-angiogenic activity in the chick embryo chorioallantoic membrane (CAM) assay. Bioassay-guided fractionation and purification of the EtOH extract yielded an active anti-angiogenic compound, which was determined to be an iridoid glucoside, geniposide, by spectral analyses. Geniposide showed anti-angiogenic activity in a dose-dependent manner. It also exhibited an inhibitory effect in the range of 25-100 microM on the growth of the transformed NIH3T3 cell line.

99 citations

Proceedings ArticleDOI
Bohdan Karpinskyy1, Yong Ki Lee1, Choi Yunhyeok1, Yong-Soo Kim1, Mi-Jung Noh1, Sanghyun Lee1 
25 Feb 2016
TL;DR: A PUF structure based on the threshold voltage (Vth) difference of inverting logic gates is presented, which is implemented for secure 24b key generation in a 45nm smart card chip and achieves an error rate as low as 2.01×10-38.
Abstract: Physically unclonable function (PUF) circuits are for generating unique secure keys or chip IDs based on intrinsic properties of each chip itself [1–2]. PUFs are a step forward to improve the security level compared to traditional NVM (non-volatile memory) solutions (FUSEs, EEPROM/FLASH, etc.) because they resolve security issues, such as active data-probing, transferring the security key from outside, etc. Since the MOSFET mismatch (e.g. size, doping concentration, mobility and oxide thickness) due to process variations cannot be fully controlled, PUFs, which are based on such phenomena, cannot be replicated. Unfortunately, the PUF output is erroneous by nature, as caused by thermal noise, voltage/temperature influence, aging effects, etc. The stability issue must be overcome since standard security applications, such as data encryption and digital signatures, have zero error-tolerance. In this work, a PUF structure based on the threshold voltage (Vth) difference of inverting logic gates is presented, which is implemented for secure 24b key generation in a 45nm smart card chip. The key is used as part of an encryption key and achieves an error rate as low as 2.01×10−38. The PUF system is also scalable for a larger key size.

98 citations

Patent
29 Oct 2003
TL;DR: In this article, an implementation method for simplifying a complicated message-passing function in a decoder for decoding block codes encoded with LDPC codes and only using a summator and a shifter to simplify the hardware structure of the decoder is presented.
Abstract: Disclosed is an implementation method for simplifying a complicated message-passing function in a decoder for decoding block codes encoded with low-density parity-check (LDPC) codes and only using a summator and a shifter to simplify the hardware structure of the decoder, in which method the input interval of the message-passing function for binary representation of a message input is divided and the respective divided intervals are linearized to allow the calculation of the output of the message-passing function without using a memory. Based on the fact that the message-passing function is similar in structure to an exponential function, the linearized intervals are set to make the maximum value expressible in each digit of the binary representation as the boundary of the intervals.

90 citations

Journal ArticleDOI
TL;DR: The technical considerations for enhancing the VLC physical layer are overviewed by summarizing the state-of-the-art advancements in modulation and coding technologies dedicated to VLC systems and the technical challenges under lighting restrictions are described.
Abstract: The recent interest in short-range optical wireless communication technology driven by the widespread deployment of solid state lighting has led to significant efforts on the standardization of visible light communication. In such efforts, the consideration of dimming support poses fundamental challenges on the VLC system design that have not been addressed elsewhere. This article overviews the technical considerations for enhancing the VLC physical layer by summarizing the state-of-the-art advancements in modulation and coding technologies dedicated to VLC systems. In addition, the technical challenges for system enhancement under lighting restrictions are described.

90 citations


Cited by
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01 Jan 2014
TL;DR: These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care.
Abstract: XI. STRATEGIES FOR IMPROVING DIABETES CARE D iabetes is a chronic illness that requires continuing medical care and patient self-management education to prevent acute complications and to reduce the risk of long-term complications. Diabetes care is complex and requires that many issues, beyond glycemic control, be addressed. A large body of evidence exists that supports a range of interventions to improve diabetes outcomes. These standards of care are intended to provide clinicians, patients, researchers, payors, and other interested individuals with the components of diabetes care, treatment goals, and tools to evaluate the quality of care. While individual preferences, comorbidities, and other patient factors may require modification of goals, targets that are desirable for most patients with diabetes are provided. These standards are not intended to preclude more extensive evaluation and management of the patient by other specialists as needed. For more detailed information, refer to Bode (Ed.): Medical Management of Type 1 Diabetes (1), Burant (Ed): Medical Management of Type 2 Diabetes (2), and Klingensmith (Ed): Intensive Diabetes Management (3). The recommendations included are diagnostic and therapeutic actions that are known or believed to favorably affect health outcomes of patients with diabetes. A grading system (Table 1), developed by the American Diabetes Association (ADA) and modeled after existing methods, was utilized to clarify and codify the evidence that forms the basis for the recommendations. The level of evidence that supports each recommendation is listed after each recommendation using the letters A, B, C, or E.

9,618 citations

Journal Article
TL;DR: A diagnosis of gestational diabetes mellitus (GDM) (diabetes diagnosed in the second or third trimester of pregnancy that is not clearly overt diabetes) or chemical-induced diabetes (such as in the treatment of HIV/AIDS or after organ transplantation)
Abstract: 1. Type 1 diabetes (due to b-cell destruction, usually leading to absolute insulin deficiency) 2. Type 2 diabetes (due to a progressive insulin secretory defect on the background of insulin resistance) 3. Gestational diabetes mellitus (GDM) (diabetes diagnosed in the second or third trimester of pregnancy that is not clearly overt diabetes) 4. Specific types of diabetes due to other causes, e.g., monogenic diabetes syndromes (such as neonatal diabetes and maturity-onset diabetes of the young [MODY]), diseases of the exocrine pancreas (such as cystic fibrosis), and drugor chemical-induced diabetes (such as in the treatment of HIV/AIDS or after organ transplantation)

2,339 citations

Patent
14 Jun 2016
TL;DR: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation as discussed by the authors, which is the basis for the representation presented in this paper.
Abstract: Newness and distinctiveness is claimed in the features of ornamentation as shown inside the broken line circle in the accompanying representation.

1,500 citations

Journal ArticleDOI
TL;DR: This paper provides a comprehensive survey on VLC with an emphasis on challenges faced in indoor applications over the period 1979-2014.
Abstract: Visible Light Communication (VLC) is an emerging field in Optical Wireless Communication (OWC) which utilizes the superior modulation bandwidth of Light Emitting Diodes (LEDs) to transmit data. In modern day communication systems, the most popular frequency band is Radio Frequency (RF) mainly due to little interference and good coverage. However, the rapidly dwindling RF spectrum along with increasing wireless network traffic has substantiated the need for greater bandwidth and spectral relief. By combining illumination and communication, VLC provides ubiquitous communication while addressing the shortfalls and limitations of RF communication. This paper provides a comprehensive survey on VLC with an emphasis on challenges faced in indoor applications over the period 1979–2014. VLC is compared with infrared (IR) and RF systems and the necessity for using this beneficial technology in communication systems is justified. The advantages of LEDs compared to traditional lighting technologies are discussed and comparison is done between different types of LEDs currently available. Modulation schemes and dimming techniques for indoor VLC are discussed in detail. Methods needed to improve VLC system performance such as filtering, equalization, compensation, and beamforming are also presented. The recent progress made by various research groups in this field is discussed along with the possible applications of this technology. Finally, the limitations of VLC as well as the probable future directions are presented.

687 citations

Journal ArticleDOI
TL;DR: This critical Review focuses on the evolution of the hybrid ion capacitor (HIC) from its early embodiments to its modern form, focusing on the key outstanding scientific and technological questions that necessitate further in-depth study.
Abstract: In this critical Review we focus on the evolution of the hybrid ion capacitor (HIC) from its early embodiments to its modern form, focusing on the key outstanding scientific and technological questions that necessitate further in-depth study. It may be argued that HICs began as aqueous systems, based on a Faradaic oxide positive electrode (e.g., Co3O4, RuOx) and an activated carbon ion-adsorption negative electrode. In these early embodiments HICs were meant to compete directly with electrical double layer capacitors (EDLCs), rather than with the much higher energy secondary batteries. The HIC design then evolved to be based on a wide voltage (∼4.2 V) carbonate-based battery electrolyte, using an insertion titanium oxide compound anode (Li4Ti5O12, LixTi5O12) versus a Li ion adsorption porous carbon cathode. The modern Na and Li architectures contain a diverse range of nanostructured materials in both electrodes, including TiO2, Li7Ti5O12, Li4Ti5O12, Na6LiTi5O12, Na2Ti3O7, graphene, hard carbon, soft carbo...

663 citations