A study on the Reconfigurable IFFT/FFT Processor Design for a Multi-mode Modem

전형구 동의대학교 산업기술개발연구소 2005 産業技術硏究誌 Vol.19 No.-

It is expected to use IEEE 802.1x series in high speed data rate wireless communications. In addition, it is necessary for the physical layer modem to be a variable or reconfigurable form so that the modem can access to any kind of network, regardless of the access specification of the network. Since IEEE 802.1x series have different size of IFFT/FFT, respectively, the modem chip should have a hardware structure with variable point IFFT/FFT function. In this paper, we propose a design method of variable point IFFT/FFT process. With the method, we can implement a reconfigurable modem in one chip in which different kinds of OFDM modem can be easily integrated. In the proposed method, the input signal samples is rearranged by zero insertion or interpolation, and then the IFFT/FFT output is decimated or selected to obtain the final IFFT/FFT output we want. The proposed method is expected to be useful for developing an integrated multi-mode OFDM modem.

상표확장의 정보전이 이론과 신념변화모형에 관한 연구

김형길,정구도 제주대학교 관광과경영경제연구소 2002 産經論集 Vol.17 No.-

한국인 6-17세 아동의 성장과 발육에 관한 준종단적 연구 : 제 1 세부과제: 치열궁의 성장 변화 Part Ⅰ: Growth and Development of Arch Form

손병화,김형순,이정구,김석현 대한치과교정학회 1996 대한치과교정학회지 Vol.26 No.3

본 연구는 한국인 남,녀 6세에서 17세 사이의 악안면 성장과 발육에 관한 준종단적 연구의 일부로 시행되었으며 3년간에 걸쳐 남,녀 아동 736명을 대상으로 치열궁의 성장변화를 관찰하고자 치아의 근원심 폭경, 견치간 폭경, 구치간 폭경, 견치 치열궁 장경, 구치 치열궁 장경 그리고 치열궁 주위경을 측정하여 연령별, 성별 평균과 표준편차를 구하고 도표로 표시하여 다음과 같은 결론을 얻었다. 결론 1. 치아의 근원심 폭경 측정에서 상악은 중절치, 제2대구차, 하악은 견치, 제2대구치에서 남,녀 성차이를 인정 할 수 있었다. 2. 견치간 폭경은 11세까지 완만히 증가하는 양상을 보였다. 3. 구치간 폭경은 상악에서는 지속적으로 증가하는 양상을 보이며 그 양상은 9세에서 14세사이에서 가장 두드러지게 나타났다. 하악에서는 9세까지는 다양한 변화를 보이며 이후 14세까지 다소 증가하는 경향을 보였다. 4. 견치 치열궁 장경은 상악에서는 13세까지, 하악에서는 11세까지 증가하는 양상을 보였다. 5. 구치 이열궁 장경은 남자에서는 10세, 여자에서는 9세까지 증가하는 경향을 보이며, 이러한 변화는 상악에서 더 뚜렷하게 나타났다. 이후 상하악 모두에서 감소하는 경향을 보이며 이는 상악에서는 15세, 하악에서는 12세 사이에서 두드러졌다. 6. 치열궁 주위경은 상,하악 모두 10세까지 증가하는 경향을 보이며 그 양상은 상악에서 더 크게 나타났다. 반면에 10세와 14세 사이에서는 감소하는 경향을 보이며 그 양상은 하악에서 더 크게 나타났다. This study was carried out as a part of the semi-longitudinal study on growth and development of Korean children with purpose of observing the growth change in arch form, 736 pairs of study models were taken for 3 years, Mesio-distal diameter of each tooth, intercanine width, intermolar width, canine arch depth, molar arch depth and arch perimeters were measured. Afterwards, mean value and each standard deviation of each age group and each gender were obtained, and corresponding graphs were drawn. The following conclusions were obtained: 1. Mesio-distal diameters of maxillary central incisor, maxillary 2nd molar, mandibular canine, and mandibular 2nd molar showed statistical differences between boys and girls. 2. Intercanine width shows a gradual increase until age of 11. 3. Intermolar width in maxilla shows continuous increase, and the tendency of increase is more apparent between age of 9 and 14, In mandible, various pattern was shown until age of 9,and after, a slight increase. 4. Canine arch depth shows the increasing tendency until age of 13 in maxilla and 11 in mandible. 5. Molar arch depth shows the pattern of increase until age of 10 in male and 9 in female, which is more apparent in maxilla. After age of 9 or 10, dereasing pattrn was significantly shown until age of 15 in maxilla and age of 12 in mandible. 6. Arch perimeters in maxilla and mandible showed gradual increase until age of 10, and the tendency of increase was more apparent in maxilla; however, between the age of 10 and 14, arch perimeters of maxilla and mandible showed gradual decrease which was more apparent in mandible.

Expression and Characterization of Truncated Recombinant Human Cytochrome P450 2J2

Hyoung-Goo Park,Young-Ran Lim,Songhee Han,Donghak Kim 한국독성학회 2014 Toxicological Research Vol.30 No.1

The human cytochrome P450 2J2 catalyzes an epoxygenase reaction to oxidize various fatty acids including arachidonic acid. In this study, three recombinant enzyme constructs of P450 2J2 were heterologously expressed in Escherichia coli and their P450 proteins were successfully purified using a Ni<SUP>2+</SUP>-NTA affinity column. Deletion of 34 amino acid residues in N-terminus of P450 2J2 enzyme (2J2-D) produced the soluble enzyme located in the cytosolic fraction. The enzymatic analysis of this truncated protein indicated the typical spectral characteristics and functional properties of P450 2J2 enzyme. P450 2J2-D enzymes from soluble fraction catalyzed the oxidation reaction of terfenadine to the hydroxylated product. However, P450 2J2-D enzymes from membrane fraction did not support the P450 oxidation reaction although it displayed the characteristic CO-binding spectrum of P450. Our finding of these features in the N-terminal modified P450 2J2 enzyme could help understand the biological functions and the metabolic roles of P450 2J2 enzyme and make the crystallographic analysis of the P450 2J2 structure feasible for future studies.

Option Markets and the Value of CSR

Hyoung-Goo Kang(강형구),Sol Kim(김솔),Geul Lee(이글) 한국경영학회 2017 한국경영학회 통합학술발표논문집 Vol.2017 No.08

We introduce an innovative method to quantify the risk-management benefit of Corporate Social Responsibility (CSR). Option-implied volatility captures the expectations of financial markets of future risk and uncertainty of a firm. Therefore, if CSR produces risk management benefits, CSR should reduce implied volatility. We find that CSR and implied volatility show a negative concurrent correlation after controlling for other variables. In addition, the greater the CSR, the lower the future implied volatility. These findings are consistent with the view that CSR creates risk management benefits to a firm, and financial markets strongly appreciate the benefit. Hence, financial engineers in charge of derivative pricing should take into account strategic management variables.

Option Marketsand the Value of CSR: Evidence from Option-Implied Volatility

Hyoung-Goo Kang,Sol Kim,Geul Lee 한국윤리경영학회 2017 한국윤리경영학회 학술대회 발표논문집 Vol.2017 No.3

We introduce an innovative method to quantify the risk-management benefit ofCorporate Social Responsibility(CSR). Option-implied volatility captures the expectations of financial marketsof future risk and uncertainty ofa firm. Therefore, if CSR produces risk management benefits, CSR should reduce implied volatility. We find that CSR and implied volatility show a negative concurrent correlation after controlling for other variables. In addition, the greater the CSR, the lower the future implied volatility. These findings are consistent with the view that CSR creates risk management benefits to a firm, and financial markets stronglyappreciate the benefit. Hence, financial engineers in charge of derivative pricing should take into account strategic management variables.

Bitcoin and Emotions

Hyoung-Goo Kang,Kyounghun Bae,Joon Chae,Bonha Koo 한국경영정보학회 2019 한국경영정보학회 학술대회논문집 Vol.2019 No.11

We examine how investor emotions and Bitcoin price influence each other using high-frequency data and NLP analysis. Emotions regarding Bitcoin are extracted from an online chatting window at one of the largest cryptocurrency exchanges in Korea. To control for global factors, we analyze relative Bitcoin prices, Korean premium, and differences between Korean exchange and other global prices. We aggregate intraday high-frequency data at five-minute intervals from October 8, 2017 to January 23, 2018. The identified emotions predict the return and volatility of Korean premium five minutes ahead. The results are economically significant: simple trading strategies using the relationship between emotions and Bitcoin prices generate profits. Consequently, investor emotions drive Bitcoin prices, suggesting irrational crypto-markets that rational speculators can exploit, but policy makers need to address.

Examining the Generative Artificial Intelligence Landscape: Current Status and Policy Strategies

Hyoung-Goo Kang,Aram Moon,Sam Seongmin Jeon 한국경영학회 2023 한국경영학회 통합학술발표논문집 Vol.2023 No.8

Purpose: This article proposes a framework to elucidate the structural dynamics of the generative AI ecosystem. It also outlines the practical application of this proposed framework through illustrative policies, with a specific emphasis on the development of the Korean generative AI ecosystem and its implications of platform strategies at AI platform-squared. Design/methodology/approach: The core of this paper centers around the interrelations within AI platforms, with a distinct focus on hierarchical structures and power dynamics. We propose a comprehensive classification scheme within generative AI ecosystems, including app builders, technology partners, app stores, foundational AI models operating as operating systems, cloud services, and chip manufacturers. Predictions: The market competitiveness for both app builders and technology partners will be highly contingent on their ability to effectively navigate the customer decision journey (CDJ) while offering localized services that fill the gaps left by foundational models. The strategically important platform of platforms in the generative AI ecosystem (i.e., AI platform-squared) is constituted by app stores, foundational AIs as operating systems, and cloud services. A few companies, primarily in the U.S. and China, are projected to dominate this AI platformsquared, and consequently, they are likely to become the primary targets of nonmarket strategies by diverse governments and communities. Korea still has chances in AI platform-squared, but the window of opportunities is narrowing. Recommendations: A cautious approach is necessary when considering potential regulations for domestic large AI models and platforms. Hastily importing foreign regulatory frameworks and non-market strategies, such as those from Europe, could overlook the essential hierarchical structure that our framework underscores. Our study suggests a clear strategic pathway for Korea to emerge as a generative AI powerhouse. As one of the few countries boasting significant companies within the foundational AI models (which need to collaborate) and chip manufacturing sectors, it is vital for Korea to leverage its unique position and strategically penetrate the platform-squared segment - app stores, operating systems, and cloud services. Given the potential network effects and winner-takes-all dynamics in AI platform-squared, this endeavor is of immediate urgency. To facilitate this transition, it is recommended that the government implement promotional policies that strategically nurture these AI platform-squared, rather than restrict them through regulations and stakeholder pressures.

Enhanced Purification of Recombinant Rat NADPH-P450 Reductase by Using a Hexahistidine-Tag^s

( Hyoung-goo Park ),( Young-ran Lim ),( Songhee Han ),( Dabin Jeong ),( Donghak Kim ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.5

NADPH-P450 reductase (NPR) transfers electrons from NADPH to cytochrome P450 and heme oxygenase enzymes to support their catalytic activities. This protein is localized within the endoplasmic reticulum membrane and utilizes FMN, FAD, and NADPH as cofactors. Although NPR is essential toward enabling the biochemical and pharmacological analyses of P450 enzymes, its production as a recombinant purified protein requires a series of tedious efforts and a high cost due to the use of NADP+ in the affinity chromatography process. In the present study, the rat NPR clone containing a 6× Histidine-tag (NPR-His) was constructed and heterologously expressed. The NPR-His protein was purified using Ni²⁺-affinity chromatography, and its functional features were characterized. A single band at 78 kDa was observed from SDS-PAGE and the purified protein displayed a maximum absorbance at 455 nm, indicating the presence of an oxidized flavin cofactor. Cytochrome c and nitroblue tetrazolium were reduced by purified NPR-His in an NADPH-dependent manner. The purified NPR-His successfully supported the catalytic activities of human P450 1A2 and 2A6 and fungal CYP52A21, yielding results similar to those obtained using conventional purified rat reductase. This study will facilitate the use of recombinant NPR-His protein in the various fields of P450 research.

An Option Embedded Novel Military Service System based on Cognitive Bias Theories

( Hyoung-goo Kang ),( Byungsuk Han ) 한국파생상품학회(구 한국선물학회) 2020 선물연구 Vol.28 No.3

We hypothesize that cognitive biases such as nostalgia, rosy retrospection, overconfidence, fading-affect bias, and prospect theory affect how to serve in the military. The behaviors of those expecting military service and those completed the service differ significantlyin evaluating the self and social value of the human capital during the military service. This difference corresponds to the predictions of the cognitive-bias literature. We test propositions in option framework. Our experimental design proposes a novel military system, a hybrid of conscription and voluntary systems. Our results are consistent with the hypothesis, option theory, and behavioral economics literature.