http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Effective Test Bed of 380-V DC Distribution System Using Isolated Power Converters
Myung-Hyo Ryu,Ho-Sung Kim,Ju-Won Baek,Heung-Geun Kim,Jee-Hoon Jung Institute of Electrical and Electronics Engineers 2015 IEEE transactions on industrial electronics Vol. No.
<P>This paper proposes an effective test bed for a 380-V dc distribution system using isolated power converters. The proposed test-bed system is composed of a grid-interactive ac-dc converter for regulating the dc-bus voltage, a bidirectional converter for the battery power interface, a renewable energy simulator, dc home appliances modified from conventional ac components, a dc distribution panel board, and its monitoring system. This paper discusses three isolated power converters, i.e., a bidirectional ac-dc converter, a bidirectional dc-dc converter, and a unidirectional dc-dc converter for the effective power interface of a dc bus. These isolated power converters are designed using a dual-active-bridge converter and the resonant topologies of CLLC and LLC. The proposed test-bed system was implemented using a 5-kW bidirectional ac-dc prototype converter, a 3-kW bidirectional dc-dc prototype converter, and a 3-kW unidirectional dc-dc prototype converter. Finally, the performance of the test-bed system has been verified using practical experiments of load variations and bidirectional power flow, employing the prototype converters.</P>
Myung Hyo Ryu,Byungcho Choi,Heung Geun Kim,Young Kil Cha 전력전자학회 1998 ICPE(ISPE)논문집 Vol.- No.-
This paper proposes a new single-stage, single-switch AC/DC converter based on the boost power factor correction (PPC) cell. The converter offers both high power factor and high efficiency. To reduce the dc voltage on the energy storage capacitor, the dc bus voltage feedback method was used. A 100W (5V/20A) prototype was built and tested to show the validity of the proposed converter.<br/>
Ryu Myung-Hyo,Kim Jong-Hyun,Baek Ju-Won,Cha Hon-Nyong The Korean Institute of Electrical Engineers 2006 Journal of Electrical Engineering & Technology Vol.1 No.3
In this paper, the electrical characteristics of the contactless transformer is presented using the conventional coupled inductor theory. Compared with the conventional transformer, the contactless transformer has a large airgap, long primary wire and multi-secondary wire. As such, the contactless transformer has a large leakage inductance, small magnetizing inductance and poor coupling coefficient. Therefore, large magnetizing currents flow through the entire primary system due to small magnetizing inductance, resulting in low overall system efficiency. In high power applications, the contactless transformer is so bulky and heavy that it needs to be split by some light and small transformers. So, the contactless transformer needs several small transformer modules that are connected in series or parallel to transfer the primary power to the secondary one. This paper shows the analysis and measurement results of each contactless transformer module and comparison results between the series- and parallel-connection of the contactless transformer. The results are verified on the simulation based on the theoretical analysis and the 30kW experimental prototype.
Self-reported Food Intolerance in Korean Patients With Irritable Bowel Syndrome
Hyo Jeong Lee,Hyun Jin Kim,Eun Hee Kang,Kee Wook Jung,Seung-Jae Myung,Yang Won Min,Chang Hwan Choi,Han Seung Ryu,Jong Kyoung Choi,Joong Goo Kwon,Kyoung Sup Hong,Kyung Sik Park 대한소화기 기능성질환∙운동학회 2019 Journal of Neurogastroenterology and Motility (JNM Vol.25 No.2
Background/Aims Various foods trigger and/or worsen the symptoms of irritable bowel syndrome (IBS). However, Korean food-related gastrointestinal (GI) symptoms in IBS patients have not yet been investigated. This study aims to evaluate the prevalence of self-reported food intolerance in Korean IBS patients and determine the Korean food items and food groups perceived by patients to worsen their GI symptoms. Methods We recruited 393 study subjects, comprising 101 IBS patients, 167 symptomatic non-IBS subjects, and 125 control subjects. All participants completed a questionnaire to identify the most problematic foods and assess the occurrence of GI symptoms caused by 119 Korean food items. They also completed the validated Rome III questionnaire for IBS. Results The prevalence of self-reported food intolerance in Korean IBS patients was 79.2%, which was significantly higher than that in control subjects (44.8%, P < 0.001). The most problematic foods reported by IBS patients who experienced food intolerance were high-fat foods (25.0%), gluten foods (23.8%), spicy foods (15.0%), and dairy products (15.0%). A total of 63.4% of IBS patients reported GI symptoms related to the consumption of foods high in fermentable oligo-, di-, mono-saccharides, and polyols (FODMAP), while 48.5% of IBS patients reported symptoms associated with high-fat foods. Gas problems and loose stools were the most frequently reported symptoms. Conclusions A large proportion of Korean IBS patients complained of intolerance to certain food items, with high-fat and high-FODMAP foods being the main triggers. This study provides a basis for planning food intervention studies for Korean IBS patients. Background/Aims Various foods trigger and/or worsen the symptoms of irritable bowel syndrome (IBS). However, Korean food-related gastrointestinal (GI) symptoms in IBS patients have not yet been investigated. This study aims to evaluate the prevalence of self-reported food intolerance in Korean IBS patients and determine the Korean food items and food groups perceived by patients to worsen their GI symptoms. Methods We recruited 393 study subjects, comprising 101 IBS patients, 167 symptomatic non-IBS subjects, and 125 control subjects. All participants completed a questionnaire to identify the most problematic foods and assess the occurrence of GI symptoms caused by 119 Korean food items. They also completed the validated Rome III questionnaire for IBS. Results The prevalence of self-reported food intolerance in Korean IBS patients was 79.2%, which was significantly higher than that in control subjects (44.8%, P < 0.001). The most problematic foods reported by IBS patients who experienced food intolerance were high-fat foods (25.0%), gluten foods (23.8%), spicy foods (15.0%), and dairy products (15.0%). A total of 63.4% of IBS patients reported GI symptoms related to the consumption of foods high in fermentable oligo-, di-, mono-saccharides, and polyols (FODMAP), while 48.5% of IBS patients reported symptoms associated with high-fat foods. Gas problems and loose stools were the most frequently reported symptoms. Conclusions A large proportion of Korean IBS patients complained of intolerance to certain food items, with high-fat and high-FODMAP foods being the main triggers. This study provides a basis for planning food intervention studies for Korean IBS patients.
Ryu, Yeon-Mi,Myung, Seung-Jae,Park, Young Soo,Yang, Dong-Hoon,Song, Ho June,Jeong, Jin-Yong,Lee, Sun Mi,Song, Miyeoun,Kim, Do Hoon,Lee, Hyo-Jeong,Park, Soo-Kyung,Fink, Stephen P.,Markowitz, Sandy D.,J American Association for Cancer Research 2013 Cancer prevention research Vol.6 No.4
<P><I>Helicobacter pylori</I> (<I>H. pylori</I>) infection induces a chronic inflammatory response, which promotes gastric carcinogenesis. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) plays a key role as a tumor suppressor in gastrointestinal cancers. The aim of this study was to elucidate the role of 15-PGDH in gastric carcinogenesis associated with <I>H. pylori</I>. 15-PGDH expression in gastric biopsies from <I>H. pylori</I>–infected (<I>n</I> = 25) and noninfected (<I>n</I> = 15) subjects was analyzed by quantitative real-time PCR, Western blot analysis, and immunohistochemistry. 15-PGDH DNA methylation was evaluated by methylation-specific PCR and pyrosequencing. The expression of 15-PGDH, Snail, extracellular signal–regulated kinase (ERK)1/2, TLR4, and MyD88 in response to <I>H. pylori</I> infection was assessed by immunoblot analysis. Compared with negative specimens, <I>H. pylori</I>–positive specimens had 2-fold lower 15-PGDH mRNA levels and significantly less 15-PGDH protein. In four <I>H. pylori–</I>infected subjects with longitudinal follow-up, the suppression of 15-PGDH expression was reversed by <I>H. pylori</I> eradication therapy. In parallel with suppressing 15-PGDH expression, <I>H. pylori</I> infection activated expression of TLR4 and MyD88 expression, increased levels of phospho-ERK1/2, and increased expression of EGF receptor (EGFR)-Snail. Inhibition of Snail and MyD88 reversed suppression of 15-PGDH expression, and siMyD88 reduced phosphorylated ERK1/2. Similarly, treatment with an ERK1/2 and EGFR inhibitor also restored 15-PGDH expression. <I>H. pylori</I> appeared to promote gastric carcinogenesis by suppressing15-PGDH. This process is mediated by the TLR4/MyD88 pathway via ERK1/2 or EGFR-Snail transcriptional regulation. 15-PGDH may be a useful marker and a potential therapeutic target in <I>H. pylori</I>–induced gastric carcinogenesis. <I>Cancer Prev Res; 6(4); 349–59. ©2013 AACR.</I></P>