블루투스 시스템의 스케쥴링 기법에 관한 연구

이왕은,박찬정 국립7개대학공동논문집간행위원회 2004 공업기술연구 Vol.4 No.-

With the fast development of wireless communication system, the demand of various method for the wireless communication is on the increase. Bluetooth communication is based on piconet, which is composed by one master and has the maximum number of slaves seven. In a bluetooth system, a master can use seven AM_ADDRs at the most. So a slave which wants to communicate with the master has to wait until it gets a AM_ADDR from the master. Also the bluetooth system has a problem in processing, according to a linked order without considering the quality of packet. This paper presents a new scheduling scheme: the priority queue algorithm scheduling scheme. In this scheme, each slave has the priority order. We use five grades that determine the priority order. We present simulation results of the proposed scheme which indicate more significant improvement than traditional schemes, as shown in the processing time of the control packet and latency.

무용수의 운동중 호흡ㆍ 순환계 반응의 비교

변재경,주기찬,백왕일 韓國舞踊敎育學會 2000 韓國舞踊敎育學會誌 Vol.11 No.1

The purpose of this study was to compare the difference of cardiorespiratoy responses to exercise among three tapes of dancers, and to verify their cardiorespiratory charcteristics due to specificity of dance buck as the pattern of limb movement, velocity of motion and so forth The subject of this study were 44 female collegiate students and comprised of each 11 Korean dancers, modern dancers, ballet dancers, and untrained students. The dependent variables were minute ventilation respiratory frequency, tidal volume, exercise duration, oxygen uptake, heart rate, respiratory exchange ratio, O2 purse, and anaerobic threshold not only at 3minutes, 6minutes and 9minutes during graded exorcise test but also maximum level. With above experimental precess, the results were gained as follows: First, the minute ventilation of the ballet group progressively increased with the increase of workload of treadmill at 3minutes,6minutes, 9minutes and maximum level. That of the control group was significantly high in comparison with that of the ballet group at 3minutes, 6minutes and 9minutes, but there was no significant differences at maximum level. Second, the respiratory frequency, tidal volume and O2 purse progressively increased in all groups with the increase of workload at 3minutes, 6minutes, 9minutes and maximum level, but there was no statistically significant differences. Third, as for the mean exorcise duration of all the group, the ballet dancers showed 10min. 27sec, the Korean dancers 10min, 15sec, the modern dancers 9min-56sec and the control group 9min. 36sec. The control group was significantly high in comparison with the ballet group. Fourth, the oxygen uptake(VO2) progressively increased with the increase of workload in all the dancers' groups. At 6 minutes, the control group was significantly high in ccmparison with the modern dancers. At 9 minutes, the ballet dancers was signiflcantly high in comparison with the modern dancers. At maximum level, the ballet dancers was signiscantly high in comparison with the rest three groups. Fifth, the respiratory exchange ratio progressively increased with the increase of workload in all groups. At 3 minutes, the modern dancer was significantly high in comparison with the control group, while at 9 minutes, the control group was significantly high in comparison with the Korean dancers. Sixth, the heart rate (HR) increased progressively in all groups with the increase of workload. At 9 minutes, the HR of the control group was significantly high in comparison with that of the rest three groups. Seventh, as for anaerobic threshold according to % VO2 max, the ballet dancers was 67.24 6.74, the Korean dancers 62.30 4.50, the modern dancers 67.32 8.30, and the control group 63.30 4.50. There was no significant differences in anaerobic threshold of three types of dancers. With the above results, the groups of ballet dancers and modern dancers were significantly high in oxygen uptake, heart rate and exercise duration in comparison with other groups because the groups of ballet dancers and modem dancers do a lot of physical training. Moreover, the group of ballet dancers was the highest in cardiorespiratory function of all the other groups.

젤라틴에 메틸메타크릴레이트로 유화중합시킨 그라프트 폴리머의 열분해에 관한 연구

설수덕,박찬헌,신은주,왕석주 동아대학교 공과대학 부설 한국자원개발연구소 1994 硏究報告 Vol.18 No.2

Emulsion graft copolymerization with sodium lauryl sulfate(SLS) of methyl methacrylate(MMA) onto gelatin was carried out in aqueous solution by potassium persulfate(KPS) as an initiator and thermal degradation of graft copolymer was stuied using a dynamic and isothermal thermogravimetry in the stream of nitrogen gas with 60㎖/min at various heating rate from 4 to 20℃/min, and various time at 200℃ The optimun concentration on emulsion graft copolymerization of KPS, gelatin, MMA, reaction temperature and time were 12×10^(-4)㏖/ℓ, 6g, 6.3×10^(-1)㏖/ℓ, 65℃ and 4hours, respectively. The activation energy of polymerization was 17.8 ㎉/㏖. The range of activation energies of decomposition obtained using Friedman's method was between49~57 ㎉/㏖ and using Ozawa's method was between 44~52㎉/㏖. The thermal degradation of gelatin-g-PMMA is likely due to decomposition of PMMA branches dominantely.

Resistant, Path Creation, or Resilient? An Empirical Study of 87 Innovative Cities Worldwide

Chan-Yuan Wong(Chan-Yuan Wong),I-Kim Wang(I-Kim Wang) 서울대학교 경제연구소 2023 Seoul journal of economics Vol.36 No.2

This study proposes rigorous concepts of resilient, resistant, and path-creation behaviors for urban patenting and innovation studies. The study examines the responses of cities with different regional innovation system (RIS) characteristics when facing a crisis. The concepts allowed us to identify resilient cities based on crisis responses and RIS characteristics. Our study identified cities exhibiting resilient behaviors, such as Taipei and San Jose, demonstrating the ability to recover from a crisis in terms of patenting and sustain high levels of performance in localized learning. For cities with resistant behaviors, such as London, we observed that their momentum for patenting decreased, although they were endowed with RIS performance comparable to the resilient cities. Cities such as Shenzhen exhibit path-creation behaviors, demonstrating the ability to transform and achieve performances on par with the resilient cities. Unformed RIS cities demonstrate low patenting activities and have yet to configure a base for technological activities. The concept and formulated quantitative process to distinguish cities performing in patenting lay new ground for studies on urban economic resilience.

Wide-Tunable Mid Infrared Intra-cavity Optical Parametric Oscillator Based on Multi-period MgO:PPLN

Xiao-Chan Wang,Yu-Heng Wang,Hao Zheng,Hong-Zhi Liu,Yong-Ji Yu,Zi-Jian Wang 한국광학회 2021 Current Optics and Photonics Vol.5 No.1

This paper reports a tunable diode-pumped folded intracavity Q-switched singly resonant optical parametric oscillator based on multi-period MgO:PPLN. A wide tuning mid-infrared parametric lightfrom 2.78 μm to 4.17 μm was obtained in real time by changing the poled periods and temperatures. The maximum output power of 1.89 W at 3.2 μm, 1.53 W at 3.5 μm, 0.87 W at 3.8 μm and 0.486 W at 4.1 μm were achieved. The highest optical-optical conversion efficiency was 7.89%. During experiments, a range tunable output of 2.78–4.17 μm in the mid-infrared range was achieved.

A small hairpin RNA targeting myeloid cell leukemia-1 enhances apoptosis in host macrophages infected with Mycobacterium tuberculosis

Fei-yu Wang,Yu-qing Zhang,Xin-min Wang,Chan Wang,Xiao-fang Wang,Jiang-dong Wu,Fang Wu,Wan-jiang Zhang,Le Zhang 한국미생물학회 2016 The journal of microbiology Vol.54 No.4

Myeloid cell leukemia-1 (Mcl-1) plays an important role in various cell survival pathways. Some studies indicated that the expression of Mcl-1 was upregulated in host cells during infection with the virulent Mycobacterium tuberculosis strain, H37Rv. The present study was designed to investigate the effect of inhibiting Mcl-1 expression both in vivo and in vitro on apoptosis of host macrophages infected with M. tuberculosis using a small hairpin (sh)RNA. Mcl-1 expression was detected by the real time-polymerase chain reaction, western blotting, and immunohistochemistry. Flow cytometry and transmission electron microscopy were used to measure host macrophage apoptosis. We found elevated Mcl-1 levels in host macrophages infected with M. tuberculosis H37Rv. The expression of Mcl-1 was downregulated efficiently in H37Rv-infected host macrophages using shRNA. Knockdown of Mcl-1 enhanced the extent of apoptosis in H37Rv-infected host macrophages significantly. The increased apoptosis correlated with a decrease in M. tuberculosis colony forming units recovered from H37Rv-infected cells that were treated with Mcl-1-shRNA. Reducing Mcl-1 accumulation by shRNA also reduced accumulation of the anti-apoptotic gene, Bcl-2, and increased expression of the pro-apoptotic gene, Bax, in H37Rv-infected host macrophages. Our results showed that specific knockdown of Mcl-1 expression increased apoptosis of host macrophages significantly and decreased the intracellular survival of a virulent strain of M. tuberculosis. These data indicate that interference with Mcl-1 expression may provide a new avenue for tuberculosis therapy.

Parkinson’s Disease with Fatigue: Clinical Characteristics and Potential Mechanisms Relevant to α-Synuclein Oligomer

Li-Jun Zuo,Shu-Yang Yu,Fang Wang,Yanghui Xia,Ying-Shan Piao,Yang Du,Teng-Hong Lian,Rui-Dan Wang,Qiu-Jin Yu,Ya-Jie Wang,Xiao-Min Wang,Piu Chan,Sheng-Di Chen,Yongjun Wang,Wei Zhang 대한신경과학회 2016 Journal of Clinical Neurology Vol.12 No.2

Background and Purpose The aim of this study was to identify the clinical characteristics and potential mechanisms relevant to pathological proteins in Parkinson’s disease (PD) patients who experience fatigue. Methods PD patients (n=102) were evaluated using a fatigue severity scale and scales for motor and nonmotor symptoms. The levels of three pathological proteins—α-synuclein oligomer, β-amyloid (Aβ)1-42, and tau—were measured in 102 cerebrospinal fluid (CSF) samples from these PD patients. Linear regression analyses were performed between fatigue score and the CSF levels of the above-listed pathological proteins in PD patients. Results The frequency of fatigue in the PD patients was 62.75%. The fatigue group had worse motor symptoms and anxiety, depression, and autonomic dysfunction. The CSF level of α-synuclein oligomer was higher and that of Aβ1-42 was lower in the fatigue group than in the non-fatigue group. In multiple linear regression analyses, fatigue severity was significantly and positively correlated with the α-synuclein oligomer level in the CSF of PD patients, after adjusting for confounders. Conclusions PD patients experience a high frequency of fatigue. PD patients with fatigue have worse motor and part nonmotor symptoms. Fatigue in PD patients is associated with an increased α-synuclein oligomer level in the CSF

Nanoparticle-mediated inhibition of survivin to overcome drug resistance in cancer therapy

Wang, S.,Xu, Y.,Chan, H.F.,Kim, H.W.,Wang, Y.,Leong, K.W.,Chen, M. Elsevier Science Publishers 2016 Journal of controlled release Vol.240 No.-

The acquired resistance of human cancer cells to apoptosis is one of the defining hallmarks of cancer. Upregulated expression of inhibitors of apoptosis proteins (IAP) has been implicated in drug resistance in several cancers. Survivin (encoded by BIRC5), the smallest member of the IAP family, has been correlated with both the control of cell apoptosis and regulation of cell mitosis in cancer. Owing to its critical role in regulation of cell survival and development of cancer resistance, as well as its distinguishingly high level of expression in many types of cancer, survivin has long been regarded as a promising therapeutic target for cancer therapy. This review first presents an overview of the mechanism by which survivin regulates cell function, followed by a discussion of the current state of survivin-targeted therapies. We focus on the application of nanoparticulate systems to deliver survivin inhibitors, co-delivery of survivin inhibitors with chemotherapeutic agents, synchronous targeting of survivin, other drug resistant molecules, and survivin regulators. We conclude by highlighting the current limitations associated with survivin-targeted therapies and speculating on the future strategies to surmount these impediments.

Glechomanamides A-C, Germacrane Sesquiterpenoids with an Unusual Δ⁸-7,12-Lactam Moiety from <i>Salvia scapiformis</i> and Their Antiangiogenic Activity

Wang, Cai Yi,Kim, Donghwa,Zhu, Yan Kui,Oh, Dong-Chan,Huang, Ri Zhen,Wang, Heng-Shan,Liang, Dong,Lee, Sang Kook American Society of Pharmacognosy 2019 Journal of natural products Vol.82 No.11

<P>Three new germacrane sesquiterpenoid-type alkaloids with an unusual Δ<SUP>8</SUP>-7,12-lactam moiety, glechomanamides A-C (<B>1</B>-<B>3</B>), and two pairs of 7,12-hemiketal sesquiterpenoid epimers (<B>4a</B>/<B>b</B>, <B>5a</B>/<B>b</B>) were isolated from <I>Salvia scapiformis</I>. Their structures were elucidated by spectroscopic methods including HRESIMS, IR, UV, and 1D and 2D NMR and also confirmed by single-crystal X-ray diffraction analysis. The chemical transformation of compounds <B>1</B>-<B>5</B> in a solution environment was analyzed by 2D NMR spectroscopy. The aza acetallactams (<B>1</B>-<B>3</B>) were stable in organic solvent, while single crystals of the hemiacetal esters (<B>4a</B>/<B>b</B>, <B>5a</B>/<B>b</B>) underwent a tautomeric equilibrium after being dissolved. Single crystals of <B>4a</B>, <B>4b</B>, and <B>5a</B> were obtained for the first time as their naturally occurring forms. Glechomanamide B (<B>2</B>) exhibited antiangiogenic activity by suppression of vascular endothelial growth factor (VEGF)-induced tube formation through modulation of VEGF receptor 2 (VEGFR2)-mediated signaling pathways in human umbilical vascular endothelial cells (HUVECs). In addition, compound <B>2</B> also showed the significant suppression of mRNA expression associated with glycolysis and angiogenesis biomarkers in high glucose (30 mM)-induced HUVECs. These findings suggest that compound <B>2</B> might be a potential lead compound candidate for the management of diabetic retinopathy.</P> [FIG OMISSION]</BR>

Surface-Modified Gold Nanorods for Specific Cell Targeting

Chan-Ung Wang,Yoshie Arai,Insun Kim,장원희,이승현,Jason H. Hafner,정은희,Deokho Jung,권영은 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.60 No.10

Gold nanoparticles (GNPs) have unique properties that make them highly attractive materials for developing functional reagents for various biomedical applications including photothermal therapy, targeted drug delivery, and molecular imaging. For <I>in vivo</I> applications, GNPs need to be prepared with very little or negligible cytotoxicitiy. Most GNPs are, however, prepared using growth-directing surfactants, such as cetyl trimethylammonium bromide (CTAB), which are known to have considerable cytotoxicity. In this paper, we describe an approach to remove CTAB to a non-toxic concentration. We optimized the conditions for surface modification with methoxypolyethylene glycol thiol (mPEG) which replaced CTAB and formed a protective layer on the surface of GNPs. The cytotoxicity of pristine and surface-modified gold nanorods (GNRs) was measured in human cell lines derived from hepatic carcinoma, embryonic kidney, umbilical vein endothelia, and thyroid papillary carcinoma. Cytotoxicity assays revealed that treating cells with GNRs do not significantly affect cell viability except for thyroid papillary carcinoma cells. Thyroid cancer cells are more susceptible to residual CTAB, so that CTAB has to be further removed by dialysis in order to use GNRs for thyroid cell targeting. PEGylated GNRs are further modified to present monoclonal antibodies that recognize a specific surface marker, Na-I symporter, for thyroid cells. Antibody-conjugated GNRs specifically targeted human thyroid cells <I>in vitro</I>.