수중 선박소음 음향신호를 이용한 딥러닝 기반의 선박속도 추정

김범규(Bum-Kyu Kim),김한수(Hansoo Kim),김선효(Sunhyo Kim),조성호(Sungho Cho),강돈혁(Donhyug Kang),김미라(Mira Kim),장원두(Won-Du Chang) 대한전자공학회 2023 대한전자공학회 학술대회 Vol.2023 No.6

Time reversal communication using vertical particle velocity and pressure signals in shallow water

Kim, Sunhyo,Kim, Hyeonsu,Jung, Seom-kyu,Choi, Jee Woong ELSEVIER 2019 AD HOC NETWORKS Vol.89 No.-

<P><B>Abstract</B></P> <P>Acoustic communication in shallow water is characterized by multipath channels, which cause significant delay spreading, leading to inter-symbol interference. This inter-symbol interference necessarily causes a significant degradation in communication performance. Although a time reversal technique has been reported to produce satisfactory performance in multipath dominant environments, this technique requires a large receiver array covering the water column to achieve reliable communication performance. In this paper, a time reversal single-input multiple-output system using the pressure signal and the vertical component of the particle velocity is presented. The vertical component of the particle velocity was estimated using the finite difference in gradient between pressures measured by two vertically adjacent receivers. The experiment was conducted in shallow water off the south coast of Korea, where the water depth is 59 m and the bottom consists of silty clay. The results showed that the time reversal communication system based on vector quantities performed better than systems where only the pressure signals were used.</P>

Assessment of the pigeon (Columba livia) retina with spectral domain optical coherence tomography

Sunhyo Kim 대한수의학회 2021 Journal of Veterinary Science Vol.22 No.5

Background: To assess the normal retina of the pigeon eye using spectral domain optical coherence tomography (SD-OCT) and establish a normative reference. Methods: Twelve eyes of six ophthalmologically normal pigeons (Columba livia) were included. SD-OCT images were taken with dilated pupils under sedation. Four meridians, including the fovea, optic disc, red field, and yellow field, were obtained in each eye. The layers, including full thickness (FT), ganglion cell complex (GCC), thickness from the retinal pigmented epithelium to the outer nuclear layer (RPE-ONL), and from the retinal pigmented epithelium to the inner nuclear layer (RPE-INL), were manually measured. Results: The average FT values were significantly different among the four meridians (p < 0.05), with the optic disc meridian being the thickest (294.0 ± 13.9 μm). The average GCC was thickest in the optic disc (105.3 ± 27.1 μm) and thinnest in the fovea meridian (42.8 ± 15.3 μm). The average RPE-INL of the fovea meridian (165.5 ± 18.3 μm) was significantly thicker than that of the other meridians (p < 0.05). The average RPE-ONL of the fovea, optic disc, yellow field, and red field were 91.2 ± 5.2 μm, 87.7 ± 5.3 μm, 87.6 ± 6.5 μm, and 91.4 ± 3.9 μm, respectively. RPE-INL and RPE-ONL thickness of the red field meridian did not change significantly with measurement location (p > 0.05). Conclusions: Measured data could be used as normative references for diagnosing pigeon retinopathies and further research on avian fundus structure.

MicroRNA-34a Modulates Cytoskeletal Dynamics through Regulating RhoA/Rac1 Cross-talk in Chondroblasts

Kim, Dongkyun,Song, Jinsoo,Kim, Sunhyo,Park, Hyang Mi,Chun, Churl-Hong,Sonn, Jongkyung,Jin, Eun-Jung American Society for Biochemistry and Molecular Bi 2012 The Journal of biological chemistry Vol.287 No.15

<P>MicroRNAs (miRNAs) have been implicated in various cellular processes, such as cell fate determination, cell death, and tumorigenesis. In the present study, we investigated the role of miRNA-34a (miR-34a) in the reorganization of the actin cytoskeleton, which is essential for chondrocyte differentiation. miRNA arrays to identify genes that appeared to be up-regulated or down-regulated during chondrogenesis were applied with chondrogenic progenitors treated with JNK inhibitor. PNA-based antisense oligonucleotides and miRNA precursor were used for investigation of the functional roles of miR-34a. We found that, in chick chondroprogenitors treated with JNK inhibitor, which suppresses chondrogenic differentiation, the expression levels of miR-34a and RhoA1 are up-regulated through modulation of Rac1 expression. Blockade of miR-34a via the use of PNA-based antisense oligonucleotides was associated with decreased protein expression of RhoA (a known modulator of stress fiber expression), down-regulation of stress fibers, up-regulation of Rac1, and recovery of protein level of type II collagen. miR-34a regulates RhoA/Rac1 cross-talk and negatively modulates reorganization of the actin cytoskeleton, which is one of the essential processes for establishing chondrocyte-specific morphology.</P>

Two Synthetic Ligands for Peroxisome Proliferator-Activated Receptor γ

Kim, Mina,Jeong, Sunhyo,Song, Yang-Heon,Kim, Dae-Il,Yoon, Michung THE KOREAN SOCIETY FOR BIOMEDICAL LABORATORY SCIEN 2004 Journal of biomedical laboratory sciences Vol.10 No.2

The peroxisome proliferator-activated receptor γ (PPARγ) is the molecular target for a class of drugs, the antidiabetic thiazolidnediones (TZDs). The heterodimer of PPARγ with retinoid X receptor (RXR) plays a central role in the regulation of adipogenesis and insulin sensitization. We synthesized two chemicals, DANA87 and DANA88, sharing structural characteristics with TZDs. Given this structural similarity, it was hypothesized that DANA87 and DANA88 may act as PPARγ ligands. In transient transfection assays, DANA87 and DANA88 caused slight increases in the endogenous expression of a luciferase reporter gene containing the PPAR responsive element in 3T3-L1 preadipocytes. However, DANA87 and DANA88 significantly inhibited troglitazone-induced reporter gene activation when cells were treated with a combination of DANA87 or DANA 88 and troglitazone, one of the TZDs that activate PPARγ. These results suggest that DANA87 and DANA88 are not only weak agonists of PPARγ transactivation, but also competitively antagonize troglitazone-induced PPARγ reporter activity.

한국 구화교의 한중 문장내적 코드전환(intrasentential code-switching) 구조와 문법론적 특성

김선효 ( Kim Sunhyo ) 국어학회 2020 국어학 Vol.0 No.93

이 연구는 한국 구화교 2세와 3세의 한중 문장내적 코드전환(intrasentential code-switching)을 문법론적 관점에서 분석하고 그 특성을 파악하는 데 목적을 두었다. 구화교는 1882년 임오군란 이후 중국 산동성에서 유입한 집단으로서 한국어와 중국어를 모두 사용할 수 있는 이중언어 디아스포라이다. 이들의 이중언어 구조를 형태통사적으로 분석하기 위해 자연담화를 구축하였고 이를 바탕으로 문장내적 코드전환 구조의 특성을 살펴보았다. 우선 형태론적으로는 자립형태소와 의존형태소 간의 실현에 제약이 없고, 형태소 내부에서도 코드전환이 발생하였으며, 새로운 문법표지 ‘完了以後’가 적극적으로 나타났다. 그리고 한국어 어미의 형태나 기능이 약화되었고 단어 형성에서도 ‘X하다’보다 ‘X다’ 구조가 높은 실현 빈도를 보였다. 통사적으로는 상당어구 제약(Equivalence constraints)이 적용되지 않았고, 기반언어틀(Matrix Language Frame) 이론도 화교식 변이구조에서는 적용되지 않았다. 또한 중국어 통사구조는 한국어의 간섭으로 변이를 보였으며 이러한 화교식 변이구조 현상은 화교 2세나 3세로 국한되지 않고 한국 화교 청소년 세대까지 전수되어 화석화하는 경향을 보였다. This paper scrutinized morphsyntactic characteristics of intrasentential code-switching on the base of nature discourse corpus of Old Overseas Chinese in Korea(OOCK). OOCK is one of diaspora community and bilingual speaker who entered the Korean Peninsula after IMOGULLAN War from Shandong province, China in 1882. Morphologically, intrasentential code-switching structure unrestricted to occur in between free morpheme and bound morpheme, besides could also occur inside the morphemes, and new grammatical marker wanleyihou(完了以後) appeared. In addition the meaning or function of Korean verb endings were weakened. It has also affected the word formation of 'X-da' instead of 'X-hada'. Syntactically, Equivalence Constraints were not applied to Korean-Chinese intrasentential code-switching, and the Matrix Language Frame was not accepted into OOCK variation structure. Particularly, OOCK variation structure has been changed due to Korean interference, and these structure tended to be fossilized and pass down to the young generations. (Chinese Culture University, Taiwan)

Reference values for selected dry eye tests in normal Beagle dogs: a pilot study

Youngsam Kim,Seonmi Kang,Sunhyo Kim,Jaeho Shim,Seokmin Go,Kangmoon Seo 대한수의학회 2022 Journal of Veterinary Science Vol.23 No.1

Background: Dry eye disease (DED) cannot be diagnosed by a single test because it is a multifactorial disorder of the ocular surface. Although studies on various dry eye tests (DETs) in dogs have been reported, standard criteria have not been established except for the Schirmer tear test 1 (STT-1). Objectives: To establish reference values for DETs in dogs with normal STT-1 values (≥ 15 mm/min) and to analyze the correlation between DETs. Methods: The STT-1 was performed in 10 healthy Beagle dogs (20 eyes). After 20 min, interferometry (IF) for estimating the lipid layer thickness (LLT) of the tear film, tear meniscus height (TMH), non-invasive tear breakup time (NIBUT), and meibomian gland loss rate of the upper eyelid (MGLRU) and lower eyelid (MGLRL), were measured using an ocular surface analyzer. Results: Mean values for STT-1, TMH, and NIBUT were as follows: 21.7 ± 3.4 mm/min, 0.41 ± 0.21 mm, and 19.1 ± 9.5 sec, respectively. The most frequent LLT range, measured by IF, was 30–80 nm (11 eyes), followed by 80 nm (5 eyes) and 80–140 nm (4 eyes). MGLRU ≤ 25% was measured in 11 eyes and 26%–50% in 9 eyes; MGLRL ≤ 25% in 8 eyes and 26%–50% in 12 eyes. Besides positive correlation between TMH and NIBUT (P = 0.038), there were no significant associations between DETs. Conclusions: Data obtained in this study provided normative references that could be useful for diagnosing DED and for further research into correlation between DETs in dogs with DED.

Two Synthetic Ligands for Peroxisome Proliferator-Activated Receptor γ

Mina Kim,Sunhyo Jeong,Yang-Heon Song,Dae-Il Kim,Michung Yoon 대한의생명과학회 2004 Biomedical Science Letters Vol.10 No.2

The peroxisome proliferator-activated receptor γ (PPARγ) is the molecular target for a class of drugs, the antidiabetic thiazolidnediones (TZDs). The heterodimer of PPARγ with retinoid X receptor (RXR) plays a central role in the regulation of adipogenesis and insulin sensitization. We synthesized two chemicals, DANA87 and DANA88, sharing structural characteristics with TZDs. Given this structural similarity, it was hypothesized that DANA87 and DANA88 may act as PPARγ ligands. In transient transfection assays, DANA87 and DANA88 caused slight increases in the endogenous expression of a luciferase reporter gene containing the PPAR responsive element in 3T3-L1 preadipocytes. However, DANA87 and DANA88 significantly inhibited troglitazone-induced reporter gene activation when cells were treated with a combination of DANA87 or DANA 88 and troglitazone, one of the TZDs that activate PPARγ. These results suggest that DANA87 and DANA88 are not only weak agonists of PPARγ transactivation, but also competitively antagonize troglitazone-induced PPARγ reporter activity.

한국어 ‘먹다’, 중국어 ‘吃’, 일본어 ‘食べる’의 어휘유형론적 양상과 요인

김선효 ( Kim Sunhyo ) 한국어의미학회 2022 한국어 의미학 Vol.76 No.-

The purpose of this study examined lexical typology and its factors of Korean ‘meokta(먹다)’, Chinese ‘chi(吃)’, and Japanese ‘taberu(食べる)’ based on meaning expansion and syntactic structure. Their meta-verb EAT consists of the etic meaning that is the most prototypical meaning and the emic meaning that has been expanded from the etic meaning. EAT can be divided into six types. After analyzing corpus data, EAT meaning was expanded in the order of 'Korean > Chinese > Japanese'. And there was a clear difference in the distribution. The Korean ‘meokta’ has the most diverse meaning, but the Japanese ‘taberu’ was only used to have a prototypical meaning. Because of the diachronic factor, the semantic expansion and distribution of each language have very different phenomena. Korean ‘meokta’ have been diachronically maintained their form and meaning, but Chinese ‘chi’ was changed from ‘shi(食)’ during the Ming and Qing Dynasties. Most of all, the Japanese ‘taberu’ changed from humble word to ordinary word in modern language. Consequently, it can be seen that diachronic factor has a big influence on meaning expansion.

해저면 지음향 특성에 따른 시역전 통신성능 비교

김선효(Sunhyo Kim),최지웅(Jee woong CHOI) 한국소음진동공학회 2017 한국소음진동공학회 학술대회논문집 Vol.2017 No.4