检索结果-南通市图书馆

A New FIR Filter for State Estimation and Its Application

在线全文

学校读者我要写书评

暂无评论

Journal of Computer Science & Technology 2007年第5期22卷 779-784页

作者： Pyung-soo kim Myung-Eui Lee Department of Electronics Engineering Korea Polytechnic University Shiheung CityKgunggi-DoKorea School of Information Technology Korea University of Technology and Education Cheonan City Chungnam-DoKorea

This paper proposes a new FIR （finite impulse response） filter under a least squares criterion using a forgetting factor. The proposed FIR filter does not require information of the noise covariances as well as the initial state, and has some inherent properties such as time-invariance, unbiasedness and deadbeat. The proposed FIR filter is represented in a batch form and then a recursive form as an alternative form. Prom discussions about the choice of a forgetting factor and a window length, it is shown that they can be considered as useful parameters to make the estimation performance of the proposed FIR filter as good as possible. It is shown that the proposed FIR filter can outperform the existing FIR filter with incorrect noise covariances via computer simulations. Finally, as a useful application, an image sequence stabilization problem is considered. Through this application, the FIR filtering based approach is shown to be superior to the Kalman filtering based approach.

关键词： state estimation FIR (finite impulse response) filter Kalman filter least squares forgetting factor

Early rehabilitation programs after laparoscopic colorectal surgery:Evidence and criticism

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第46期19卷 8543-8551页

作者： Duck-Woo kim sung-Bum Kang soo-Young Lee Heung-Kwon Oh Myung-Hoon In Department of Surgery Seoul National University Bundang Hospital

During the past several decades,early rehabilitation programs for the care of patients with colorectal surgery have gained *** randomized controlled trials and meta-analyses have confirmed that the implementation of these evidence-based detailed perioperative care protocols is useful for early recovery of patients after colorectal *** cared for based on these protocols had a rapid recovery of bowel movement,shortened length of hospital stay,and fewer complications compared with traditional care ***,most of the previous evidence was obtained from studies of early rehabilitation programs adapted to open colonic ***,limited evidence exists on the effects of early rehabilitation after laparoscopic rectal resection,although this procedure seems to be associated with a higher morbidity than that reported with traditional *** this article,we review previous studies and guidelines on early rehabilitation programs in patients undergoing rectal *** investigated the status of early rehabilitation programs in rectal surgery and analyzed the limitations of these *** also summarized indications and detailed protocol components of current early rehabilitation programs after rectal surgery,focusing on laparoscopic resection.

关键词： Colorectal cancer Enhanced recovery after surgery Early rehabilitation Fast-track Laparoscopy Rectal

Current status of robot-assisted gastric surgery

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastrointestinal Oncology 2011年第10期3卷 137-143页

作者： Se-Jin Baek Dong-Woo Lee sung-soo Park Seon-Hahn kim Department of Surgery Korea University College of MedicineMIS Robotic Surgery Center Korea University Medical Center Korea University Anam Hospital Seoul 136-705South Korea Robotic Surgery Center Korea University Medical Center Division of Upper GI Surgery Department of SurgeryKorea University College of MedicineMIS Division of Colorectal Department of SurgeryKorea University College of MedicineMIS

In an effort to minimize the limitations of laparoscopy,a robotic surgery system was introduced,but its role for gastric cancer is still *** objective of this article is to assess the current status of robotic surgery for gastric cancer and to predict future *** the current study was limited by its small number of patients and retrospective nature,robot-assisted gastrectomy with lymphadenectomy for the treatment of gastric cancer is a feasible and safe procedure for experienced laparoscopic *** studies have reported satisfactory results for postoperative short-term coutcomes,such as:postoperative oral feeding,gas out,hospital stay and complications,compared with laparoscopic surgery;the difference is a longer operation ***,robotic surgery showed a shallow learning curve compared with the familarity of conventional open surgery;after the accumulation of several cases,robotic surgery could be expected to result in a similar operation ***-assisted gastrectomy can expand the indications of minimally invasive surgery to include advanced gastric cancer by improving the ability to perform ***," total" robotic gastrectomy can be facilitated using a robotsewing technique and gastric submucosal tumors near the gastroesophageal junction or pylorus can be resected safely by this novel *** conclusion,robotassisted gastrectomy may offer a good alternative to conventional open or laparoscopic surgery for gastric cancer,provided that long-term oncologic outcomes can be confirmed.

关键词： Robot surgery Stomach Minimally invasive surgery

Effect of reduction in area per pass on strain distribution and microstructure during caliber rolling in twinning-induced plasticity steel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2020年第1期27卷 62-74页

作者： Joong-ki Hwang sung Jin kim School of Mechanical Engineering Tongmyong UniversityBusan 48520Republic of Korea Department of Advanced Materials Engineering Sunchon National UniversitySuncheon 57922Republic of Korea

The effects of reduction in area(RA)per pass during caliber rolling on microstructure and strain distribution of twinninginduced plasticity steel have been investigated to find solutions to make a more homogeneous material along the radial direction for wire rod *** steel wires subjected to an average RA per pass of 2.5%(skin pass caliber rolling)and 10.0%(conventional caliber rolling)were *** skin pass caliber-rolled wire was characterized as a duplex fiber texture of majorand minor.and the textures were almost same at/between center and surface area,which is totally different from those of conventional caliber rolling and wire *** skin pass caliber rolling led to more homogeneous microstructure and mechanical properties along the radial direction in comparison with the conventional caliber rolling and wire drawing due to the more homogeneous Hall-Petch hardening,dislocation hardening,and texture behavior with area,resulting in higher formability.

关键词： Twinning-induced plasticity steel Caliber rolling Deformation twin Reduction in area Skin pass

Ultimate strength of single shear bolted connections with cold-formed ferritic stainless steel

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第2期14卷 120-136页

作者： Jin-seong LIM Tae-soo kim Seung-hun kim Department of Architectural Engineering Hanbat National UniversityDaejeon 305-719Korea

This paper is focused on the structural behavior of the single shear bolted connections with thin-walled ferritic stainless *** purpose of this study is to investigate the ultimate behaviors,such as ultimate strength and fracture mode of the single shear bolted connections of thin-walled ferritic stainless steel(low cost steel) rather than austenitic stainless steel(high cost steel).Bolt arrangement and end distance parallel to the direction of applied load are considered as main variables of the test specimens for bolted *** have a constant dimension of edge distance perpendicular to the loading direction,bolt diameter,pitch,and gauge.A monotonic tensile test for specimens has been carried out and some bolted connections with long end distance showed curling(out of plane deformation) occurrence which led to strength *** ultimate behaviors such as fracture mode,ultimate strength are compared with those predicted by current design ***,conditions of curling occurrence and the strength reduction due to curling are investigated and modified strength equations are suggested considering the curling effect.

关键词： Cold-formed ferritic stainless steel Bolted connection Bolt arrangement End distance Curling Strength reduction

Generation of mesenchymal stem-like cells for producing extracellular vesicles

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2019年第5期11卷 270-280页

作者： soo kim Tae Min kim Brexogen Research Center Brexogen Inc. Seoul Songpa-gu 05718 South Korea Graduate School of International Agricultural Technology and Institute of Green- Bio Science and Technology Seoul National University Gangwon-do Pyeongchang 25354 South Korea

Mesenchymal stem cells (MSCs) are multipotent progenitor cells with therapeutic potential against autoimmune diseases, inflammation, ischemia, and metabolic disorders. Contrary to the previous conceptions, recent studies have revealed that the tissue repair and immunomodulatory functions of MSCs are largely attributed to their secretome, rather than their potential to differentiate into desired cell types. The composition of MSC secretome encompasses cytokines and growth factors, in addition to the cell-derived structures known as extracellular vesicles (EVs). EVs are membrane-enclosed nanoparticles that are capable of delivering biomolecules, and it is now believed that MSC-derived EVs are the major players that induce biological changes in the target tissues. Based on these EVs’ characteristics, the potential of EVs derived from MSC (MSC-EV) in terms of tissue regeneration and immune modulation has grown during the last decade. However, the use of MSCs for producing sufficient amount of EVs has not been satisfactory due to limitations in the cell growth and large variations among the donor cell types. In this regard, pluripotent stem cells (PSCs)-derived MSC-like cells, which can be robustly induced and expanded in vitro, have emerged as more accessible cell source that can overcome current limitations of using MSCs for EV production. In this review, we have highlighted the methods of generating MSC-like cells from PSCs and their therapeutic outcome in preclinical studies. Finally, we have also discussed future requirements for making this cell-free therapy clinically feasible.

关键词： Mesenchymal stem cells Extracellular vesicles Preclinical studies Exosomes

Effect of gadolinium incorporation on optical characteristics of YNbO_4:Eu^(3+) phosphors for lamp applications

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2012年第3期30卷 205-209页

作者： sung Hwan Choi G. Anoop Dong Wook Suh Kyung Pil kim Hyun Ju Lee Jae soo Yoo Display Materials Laboratory School of Chemical Engineering and Materials Science Chung-Ang University

Eu3＋-doped （Y,Gd）NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3＋ ions and neighboring oxygen anions. A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3＋ ions. The highest luminance for Y1-x-yGdyNbO4：Eux3＋ under 254 nm excitation was achieved at Eu3＋ concentration of 18 mol.% （x=0.18） and Gd3＋ concentration of 8.2 mol.% （y=0.082）. The luminance of Y0.738Gd0.082NbO4：Eu3＋0.18 was higher than that of a typical commercial phosphor Y2O3：Eu3＋ and the CIE chromaticity coordinate was （0.6490, 0.3506）, which was deeper than that of Y2O3：Eu3＋. The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8 μm with uniform size distribution of particles was obtained.

关键词： YNbO4:Eu oxide phosphors rare earths

Engaging in sports via the metaverse? An examination through analysis of metaverse research trends in sports

在线全文

学校读者我要写书评

暂无评论

Data Science and Management

Data Science and Management 2024年第3期7卷 181-188页

作者： Ahyun kim Sang-soo kim Department of Business Administration Dongyang Mirae UniversitySeoul08221South Korea Department of Business Administration Yong in UniversityGyeonggi-do17092South Korea

In sports, virtual spaces are sometimes utilized to enhance performance or user experience. In this study, we conducted a frequency analysis, semantic network analysis, and topic modeling using 134 abstracts obtained through keyword searches focusing on “sport(s)” in combination with “metaverse”, “augmented reality”, “virtual reality”, “lifelogging”, and “mixed reality”. First, the top 20 words were extracted through frequency analysis, and then each type of extracted word was retained to select seven words. The analysis revealed the emergence of key themes such as “user(s)”, “game(s)”, “technolog(y/ies)”, “experience(d)”, “physical”, “training”, and “video”, with variations in intensity depending on the type of metaverse. Second, the relationships between the words were reconfirmed using semantic networks based on the seven selected words. Finally, topic modeling analysis was conducted to uncover themes specific to each type of metaverse. We also found that “performance/scoring” was a prominent word across all types of metaverses. This suggests that in addition to providing enjoyment through sports, there is a high possibility that all users (both general users and athletes) utilize the metaverse to achieve positive outcomes and success. The importance of “performance/scoring” in sports may seem obvious;however, it also provides significant insights for practitioners when combined with metaverse-related keywords. Ultimately, this study has managerial implications for enhancing the performance of specialized users in the sports industry.

关键词： Sport Metaverse Frequency analysis Topic modeling Semantic network analysis

Factors influencing stereoacuity levels after surgery to correct unilateral developmental cataracts in children

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2013年第3期6卷 331-336页

作者： soo Jung Lee Wan-soo kim Department of Ophthalmology Haeundae Paik Hospital

·AIM: To evaluate factors influencing stereoacuity after surgery to correct unilateral developmental pediatric cataracts. ·METHODS: We retrospectively surveyed 110 patients who had undergone removal of unilateral acquired developmental cataracts and primary posterior chamber intraocular lens implantation between February 1992 and December 2009. In all patients, stereoacuity was assessed using the Titmus test at the last follow -up period of minimum 2 years after surgery. Patients were divided into two groups according to the extent of stereoacuity : group 1 ( = 42 ) had stereoacuity values ≤ 100sec/arc and group 2 ( =68) values >100sec/arc. The values of ten parameters associated with stereoacuity were measured in each group: Cataract types, preoperative best corrected visual acuity (BCVA) of the affected eyes, preoperative inter -ocular difference of BCVA, age at cataract surgery, operative method, secondary cataract, postoperative strabismus, postoperative BCVA of the affected eyes, postoperative inter-ocular difference of BCVA, and anisometropia. ·RESULTS: The extent of stereoacuity was significantly associated with both operative method and secondary cataract ( =0.000 and =0.016, respectively). All patients in whom the posterior capsule was preserved, had poor stereoacuity >100sec/arc. Significant correlations with the extent of stereoacuity were found with postoperative strabismus ( =0.048),postoperative BCVA of the affected eyes ( =0.002), anisometropia ( =0.034). ·CONCLUSION: Postoperative stereoacuity was better in patients who underwent either optic capture or anterior vitrectomy after posterior continuous curvilinear capsulorhexis, and who didn’t develop secondary cataracts or strabismus postoperatively. Furthermore, postoperative BCVA of the affected eyes, and anisometropia influenced the stereoacuity of the patients surgically treated for unilateral developmental pediatric cataracts. ·

关键词： anisometropia developmental cataract secondary cataract stereoacuity stereopsis strabismus unilateral pediatric cataract visual acuity