Characteristics of microwave filters based on microstrip photonicbandgap ring structures

Sung-Il Kim,Mi-Young Jang,Chul-Sik Kee,Ikmo Park,H. Lim 한국물리학회 2005 Current Applied Physics Vol.5 No.6

We study the characteristics of microstrip ring exhibiting photonic band gap properties. Since the stop band is caused by thereection of electromagnetic waves at the narrow gap introduced in the ring, the geometry of the ring can inuence on the charac-teristics of stop band. The center frequency of the stop band is determined mainly by the outer ring radius when the line width of thecircular ring is rather narrow. But it is determined mainly by the mean ring radius when the ring is not a circular form or the linewidth of circular ring is wide. The frequency range of the stop band can be varied by a reactive component mounted on the gap. Thepresence of capacitor (inductor) on the gap decreases (increases) the center frequency and the frequency range of the stop band.Moreover, the stop band can be widened by modifying the geometry of ring. These properties can be useful in the applicationsto the compact microwave circuits, tunable lters and microwave switches..

Reversal of Hückel (anti)aromaticity in the lowest triplet states of hexaphyrins and spectroscopic evidence for Baird's rule

Sung, Young Mo,Yoon, Min-Chul,Lim, Jong Min,Rath, Harapriya,Naoda, Koji,Osuka, Atsuhiro,Kim, Dongho Nature Publishing Group, a division of Macmillan P 2015 Nature chemistry Vol.7 No.5

The reversal of (anti)aromaticity in a molecule's triplet excited state compared with its closed-shell singlet ground state is known as Baird's rule and has attracted the interest of synthetic, physical organic chemists and theorists because of the potential to modulate the fundamental properties of highly conjugated molecules. Here we show that two closely related bis-rhodium hexaphyrins (R26H and R28H) containing [26] and [28] π-electron peripheries, respectively, exhibit properties consistent with Baird's rule. In the ground state, R26H exhibits a sharp Soret-like band and distinct Q-like bands characteristic of an aromatic porphyrinoid, whereas R28H exhibits a broad absorption spectrum without Q-like bands, which is typical of an antiaromatic porphyrinoid. In contrast, the T–T absorption of R26H is broad, weak and featureless, whereas that of R28H displays an intense and sharp Soret-like band. These spectral signatures, in combination with quantum chemical calculations, are in line with qualitative expectations based on Baird's rule.

Device characteristics of inkjet-printed ZnO TFTs by solution process

Lim, Sang Chul,Koo, Jae Bon,Park, Chan Woo,Jung, Soon-Won,Na, Bock Soon,Lee, Sang Suk,Chu, Hye Yong IOP Publishing 2014 Japanese journal of applied physics Vol.53 No.5

<P>We report on solution-processed n-channel ZnO thin-film transistors. We fabricated by a low-temperature process to improve their performance using inkjet printing under various conditions. The resulting films were inkjet-printed with a resolution 200 dpi using droplets of 50 mu m diameter and 35 pl volume. The characteristics of the inkjet-printed TFTs were improved significantly at an annealing temperature of 150 degrees C. The field-effect mobility, Vth, and on/off current ratio were 3.03cm(2)V(-1) s(-1), -3.3V, and 10(6), respectively. These results indicate that annealing at 150 degrees C is sufficient to obtain a mobility (mu(sat)) as large as 3.03cm(2)V(-1) s(-1). (C) 2014 The Japan Society of Applied Physics</P>

Effect of the Storage Temperature, Duration and Gamma Irradiation on the Respiration Rate and Sugar Content of Minituber 'Superior'

Lim, Ji Hyeok,Hwangbo, Jun-Kwon,Baek, Myung-Hwa,Kim, Jin-Hong,Kim, Jae-Sung,Lee, Myung Chul 한국환경농학회 2005 한국환경농학회지 Vol.24 No.1

This study was to evaluate whether ionizing gamma radiation could be applied to break the dormancy of a potato minituber. The respiration rate of the minitubers was significantly affected by the storage temperature and a low dose gamma radiation. Ionizing radiation of 8 Gy enhanced the respiration rate of the potato tuber stored at 10℃ for 20 days. The potato tuber subjected to 4 and 8 Gy after 40 days storage at 10 and 20t exhibited higher respiration rates compared to the control (non-irradiated), but not at 5℃. However, the ionizing radiation did not exhibit on significant effect on the respiration rate of the potato tuber stored for 60 days. It was observed that minitubers stored for 20 days had significant response to the storage temperature in terms of the total sugar content the higher the storage temperature, the lower the total sugar content. It was measured that the reducing sugar content was increased under the storage conditions both 5 and 10℃ for 40 days, but not to 20℃. The total sugar contents in the minituber stored for 60 days were similar to those stored for 40 days. The data was discussed on the relationships among the storage duration, temperature and ionizing radiation.

Opportunistic Noisy Network Coding for Fading Relay Networks Without CSIT

Sang-Woon Jeon,Sung Hoon Lim,Bang Chul Jung IEEE 2015 IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS Vol.14 No.11

<P>The parallel relay network is studied, in which a single source node sends a message to a single destination node with the help of N parallel relays. Channel coefficients are assumed to vary over time and channel state information (CSI) is causally available only at the receiver side (CSIR). Opportunistic noisy network coding is proposed for intelligently exploiting CSIR at each relay in a distributed manner by operating the noisy network coding scheme with adaptive compression. More specifically, each relay opportunistically vector-quantizes the collection of received symbols that is received with channel gains larger than a certain threshold. It then forwards the digital compression information to the destination node using independently generated Gaussian codes. For independent and identically distributed (i.i.d.) Rayleigh fading, the proposed scheme is shown to achieve the ergodic capacity in the large number of relays regime. Furthermore, the proposed scheme is extensively compared with several alternative schemes, the decode-forward scheme, the adaptive amplify-forward scheme, and the non-adaptive noisy network coding scheme over geometric models. We show that the new proposed scheme provides significant gain over these schemes in various cases.</P>

Performance and Cost of Disposable Biopsy Forceps in Upper Gastrointestinal Endoscopy: Comparison with Reusable Biopsy Forceps

Lim, Chul-Hyun,Choi, Myung-Gyu,Kim, Won Chul,Kim, Jin Soo,Cho, Yu Kyung,Park, Jae Myung,Lee, In Seok,Kim, Sang Woo,Choi, Kyu Yong,Chung, In-Sik The Korean Society of Gastrointestinal Endoscopy 2012 Clinical Endoscopy Vol.45 No.1

<P><B>Background/Aims</B></P><P>It is believed that disposable biopsy forceps are more costly than reusable biopsy forceps. In this study, we evaluated performance and cost of disposable forceps versus reusable forceps in esophagogastroduodenoscopic biopsy.</P><P><B>Methods</B></P><P>Between October 2009 and July 2010, we enrolled 200 patients undergoing esophagogastroduodenoscopic biopsy at Seoul St. Mary's Hospital. Biopsies were performed with 100 disposable or 5 reusable forceps by random assignment. Seventy-five additional patients were studied to estimate durability of reusable forceps. The assisting nurses estimated the performance of the forceps. The evaluation of costs included purchase prices and reprocessing costs. The adequacy of the sample was estimated according to the diameter of the obtained tissue.</P><P><B>Results</B></P><P>Performance of disposable forceps was estimated as excellent in 97.0%, good in 2.0% and adequate in 1.0%. Reusable forceps were estimated as excellent in 36.0%, good in 36.0%, adequate in 25.1% and inadequate in 2.9%. The performance of reusable forceps declined with the number of uses. The reprocessing cost of reusable forceps for one biopsy session was calculated as ₩8,021. The adequacy of the sample was excellent for both forceps.</P><P><B>Conclusions</B></P><P>Disposable forceps showed excellent performance. Considering the reprocessing costs of reusable forceps, usage of disposable forceps with a low price should be considered.</P>

Nitrate inhibits soybean nodulation by regulating expression of CLE genes

Lim, Chae Woo,Lee, Young Woo,Lee, Sung Chul,Hwang, Cheol Ho Elsevier 2014 Plant science Vol.229 No.-

<P><B>Abstract</B></P> <P>Nitrogen compounds such as nitrate act as a potential inhibitor for legume nodulation. In this study, we isolated a new CLE gene, <I>GmNIC2</I>, from nitrate-treated roots, which shares high sequence homology with nitrate-induced CLE gene <I>GmNIC1</I>. Similar to <I>GmNIC1</I>, the expression level of <I>GmNIC2</I> was not significantly altered in roots by rhizobial inoculation and was much higher in young nodules than in roots. In addition, overexpression of <I>GmNIC2</I> led to similar nodulation inhibition of transgenic hairy roots to that of <I>GmNIC1</I>, which occurred in GmNARK-dependent manner and at the local level. By analyzing GmNARK loss-of-function mutant, SS2-2, it was found that expression levels of <I>GmNIC1</I> and <I>GmNIC2</I> in the SS2-2 roots were lower than in the wild type (WT) roots in response to nitrate. In contrast to <I>GmNIC1</I> and <I>GmNIC2</I>, expressions of <I>GmRIC1</I> and <I>GmRIC2</I> genes that are related to the autoregulation of nodulation (AON) were strongly suppressed both of the soybeans during all periods of nitrate treatment and even were not induced by additional inoculation with rhizobia. Taken together, the results of this study suggest that GmNIC2, as an active homologous gene located in chromosome 13, acts locally to suppress nodulation, like GmNIC1, and nitrate inhibition of nodulation is led by fine-tuned regulation of both nitrate-induced CLEs and rhizobia-induced CLEs.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A new nitrate-induced CLE gene, <I>GmNIC2</I>, is isolated from soybean roots. </LI> <LI> GmNIC2 acts as a local signal in nitrate inhibition of nodulation, like GmNIC1. </LI> <LI> Nitrate induces lower expression of <I>GmNIC</I> genes in the supernodulation mutant. </LI> <LI> Nitrate inhibits expression of rhizobia-induced <I>CLEs</I> after rhizobial inoculation. </LI> <LI> Nitrate inhibition of nodulation is led by a fine-tune regulation between CLEs. </LI> </UL> </P>

Role of Acid and Weakly Acidic Reflux in Gastroesophageal Reflux Disease Off Proton Pump Inhibitor Therapy

Sung, Hea Jung,Cho, Yu Kyung,Moon, Sung Jin,Kim, Jin Su,Lim, Chul Hyun,Park, Jae Myung,Lee, In Seok,Kim, Sang Woo,Choi, Myung-Gye Korean Society of Neurogastroenterology and Motili 2012 Journal of Neurogastroenterology and Motility (JNM Vol.18 No.3

<P><B>Background/Aims</B></P><P>Available data about reflux patterns and symptom determinants in the gastroesophageal reflux disease (GERD) subtypes off proton pump inhibitor (PPI) therapy are lacking. We aimed to evaluate reflux patterns and determinants of symptom perception in patients with GERD off PPI therapy by impedance-pH monitoring.</P><P><B>Methods</B></P><P>We retrospectively reviewed the impedance-pH data in patients diagnosed as GERD based on results of impedance-pH monitoring, endoscopy and/or typical symptoms. The characteristics of acid and weakly acidic reflux were evaluated. Symptomatic and asymptomatic reflux were compared according to GERD subtypes and individual symptoms.</P><P><B>Results</B></P><P>Forty-two patients (22 males, mean age 46 years) were diagnosed as GERD (17 erosive reflux disease, 9 pH(+) non-erosive reflux disease [NERD], 9 hypersensitive esophagus and 7 symptomatic NERD). A total of 1,725 reflux episodes were detected (855 acid [50%], 857 weakly acidic [50%] and 13 weakly alkaline reflux [< 1%]). Acid reflux was more frequently symptomatic and bolus clearance was longer compared with weakly acidic reflux. In terms of globus, weakly acidic reflux was more symptomatic. Symptomatic reflux was more frequently acid and mixed reflux; these associations were more pronounced in erosive reflux disease and symptomatic NERD. The perception of regurgitation was related to acid reflux, while that of globus was more related to weakly acidic reflux.</P><P><B>Conclusions</B></P><P>In patients not taking PPI, acid reflux was more frequently symptomatic and had longer bolus clearance. Symptomatic reflux was more frequently acid and mixed type; however, weakly acidic reflux was associated more with globus. These data suggest a role for impedance-pH data in the evaluation of globus.</P>

Classification of maturity group in 100 Korea soybean varieties

Sang-Ouk Shin,Tae-Joung Ha,Seong-Hyu Shin,Sea-Gyu Lim,Kyung-Jin Choi,In-Yeul Baek,Keum-Yong Park,Sang-Chul Lee 한국작물학회 2008 한국작물학회 학술발표대회 논문집 Vol.2008 No.10

This study was carried out to classify Korean soybean varieties based maturity group. One hundred (100) domestic soybean varieties ( 56 for fermentation, 26 for sprouting, 17 for mixed with rice) were used and seeding date was scheduled at April 30. This experiment carried out at Yeongnam Agricultural Research Institute, NICE situated at Miryang from 2005 to 2006. Classification of maturity group in 100 soybeans was followed by Kweon et al's method (1974) The main difference between this experiment and that of Kweon et al's method (1974) were the planting region and planting date. This experiment was conducted on April 30 at Miryang while Kweon et al. was conducted on May 23 in Seoul. Results of maturity grouping of Korean soybean varieties showed that Keunol, which was represented among 3 varieties, belonged to Group 0, Seonnok and Danmi in GroupⅡ, Shinrok in GroupⅢ, Seonyu, represented by 17 cultivars, in GroupⅣ, Taekwang, having 44 cultivars in GroupⅤ, Daewon, represented by 25 cultivars in GroupⅥ, and Kwangdu and Keumdu in GroupⅦ.

Efficient and Genotype-Independent Agrobacterium-Mediated Transformation of Italian Ryegrass (Lolium multiflorum Lam.)

Sang-Hoon Lee,Ki-Won Lee,Ki-Yong Kim,Hee Chung Ji,Sei Hyung Yoon,Gi Jun Choi,Young Chul Lim 한국작물학회 2010 한국작물학회 학술발표대회 논문집 Vol.2010 No.04

Italian ryegrass (Lolium multiflorum Lam.) is one of important forage crop grass widely cultivated in Korea. The genetic manipulation of Italian ryegrass (Lolium multiflorum Lam.) necessitates a reliable and efficient, genotype-independent method of transformation. We are interested in developing molecular breeding methods to improve its nutritional quality and abiotic stress resistance. Development of a rapid and efficient transformation system is the basis for genetic manipulation of Italian ryegrass. In order to establish an efficient Agrobacterium-mediated transformation system was applied to transfer genes into seven genotypes of Italian ryegress, namely cv. 'Kogreen', 'Kopeed', 'Kowinearly', 'Kowinmaster', 'Hwasan 101', 'Hwasan104' and 'Kowinner.' The transformation system developed in this study would be useful for Agrobacterium-mediated genetic transformation of Italian ryegrass plants with genes of agronomic importance.