检索结果-南通市图书馆

Development of a system configuration for a solar powered hydrogen facility using fuzzy logic control

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11期14卷 822-834页

作者： Ying-tai LOONG Mahidzal DAHARI Hwa-jen yap Hue-yee chong Department of Mechanical Engineering Faculty of Engineering University MalayaKuala Lumpur 50603 Malaysia

Solar energy is a natural resource which can be harnessed to provide clean electricity for hydrogen production ***, this technology is not widely used because of control issues, particularly for hydrogen refuelling stations. At present,direct or DC-DC converter couplings are the most common system configurations for hydrogen refuelling stations. However, these system configurations are costly and suffer from gas shortage at hydrogen refuelling stations. Furthermore, the hydrogen produced by such system configurations varies considerably depending on the levels of solar radiation. In order to address these issues, a new system configuration is proposed, incorporating the feedback signal of the storage level in the control system. The photovoltaic(PV) system, electrolyzer, and storage tank are integrated with a fuzzy logic controller(FLC) to determine the backup current compensation for electrolyzer operation in order to obtain the minimum power required for hydrogen production. The proposed FLC is constructed with three input variables which are the PV current, hydrogen storage level, and the battery state of charge. The rules-based fuzzy inference process is based on the proposed configuration which combines the advantages of direct and DC-DC converter coupling configurations. The simulation results show that the proposed configuration offers better adaptability to variable radiation conditions compared to other methods. This gives a more promising option for ensuring the adequacy of hydrogen supply at hydrogen refuelling stations.

关键词： Hydrogen energy Solar energy Hydrogen refueling facility Fuzzy logic

Phytoplankton diversity in a tropical bay,North Borneo,Malaysia as revealed by light microscopy and Next-Generation Sequencing

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Acta Oceanologica Sinica 2022年第12期41卷 142-151页

作者： Brian Wei Khong chong Sandric Chee yew Leong Victor SKuwahara Teruaki Yoshida Unit for Harmful Algal Bloom Studies Borneo Marine Research InstituteUniversiti Malaysia SabahKota Kinabalu 88400Malaysia St.John’s Island National Marine Laboratory Tropical Marine Science InstituteNational University of SingaporeSingapore 119227Singapore Faculty of Education&Graduate School of Science and Engineering Soka UniversityHachiojiTokyo 192-8577Japan

Assessments of phytoplankton diversity in Sabah waters,North Borneo,have primarily relied on morphology-based identification,which has inherent biases and can be ***-Generation Sequencing(NGS)technology has been shown to be capable of overcoming several limitations of morphology-based *** were collected from the Sepanggar Bay over the course of the year 2018 in different monsoon ***-based identification and NGS sequencing of the V8–V9 region of the 18S LSU rDNA were used to investigate the diversity of the phytoplankton *** and NGS showed complementary results with more diatom taxa detected by microscopy whereas NGS detected smaller and rarer *** harmful algal genera in the study site comprised of Skeletonema,Margalefidinium,Pyrodinium,Takayama,and Alexandrium as detected by *** study showed that that an integrative approach of both morphological and molecular techniques could provide more comprehensive information about the phytoplankton community as the approach captured quantitative variability as well as the diversity of phytoplankton species.

关键词： phytoplankton community Next-Generation Sequencing(NGS) Sabah South China Sea

An experimental study of rotational pressure loss in rotor-stator gap

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Propulsion and Power Research 2017年第2期6卷 147-156页

作者： yew Chuan chong Dave A.Staton Markus A.Mueller John Chick Motor Design Limited 4 Scotland Street.Ellesmere SY12 OEGUnited Kingdom Institute for Energy Systems School of Engineering.University of EdinburghThe King's BuildingsEdinburgh EH93DWUnited Kingdom

The annular gap between rotor and stator is an inevitable flow path of a throughflow ventilated electrical machine,but the flow entering the rotor-stator gap is subjected to the effects of *** pressure loss and volumetric flow rate across the rotor-stator gap were measured and compared between rotating and stationary *** experimental measurements found that the flow entering the rotor-stator gap is affected by an additional pressure *** the present study,the rotational pressure loss at the entrance of rotor-stator gap is *** upon dimensional analysis,the coefficient of entrance loss can be correlated with a dimensionless parameter,*** *** investigation leads to an original correlation for the entrance loss coefficient of rotor-stator gap arisen from the Coriolis and centrifugal effects in rotating reference frame.

关键词： Pressure drop Flow network analysis Rotating machinery Rotational pressure drop Rotor-stator gap Annular gap Electrical machines

Finite element analysis of tibio-femoral contact mechanics of a customised knee spacer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Biosurface and Biotribology 2022年第2期8卷 121-128页

作者： Alex C.T.Choh Andy yew Seng Jin Yeo Desmond Y.R.chong Shi-Lu Chia Department of Orthopaedic Surgery Singapore General HospitalSingaporeSingapore Engineering Cluster Singapore Institute of TechnologySingaporeSingapore

With one-third of patients having osteoarthritis predominantly in one compartment of the knee,unicompartmental knee spacers have been introduced as a less invasive alternative to total knee ***,patients with the knee spacer implanted were seen to have persistent pain,resulting in high revision rates.A static finite element model of the knee and its interaction with a knee spacer implant at full extension and 90°flexion was used to investigate the tibio-femoral contact mechanics of the knee joint after a knee spacer *** different knee spacer designs(contoured,flat and C-shaped)were modelled and prescribed with cobalt-chrome,ultra-high molecular polyethylene and polyurethane material *** results suggested that a softer spacer is generally preferred as this helps in the conformity of knee spacer to the condyle,effectively distributing the load subjected to the *** spacers that result in high stresses resulting from lower contact areas should be avoided.

关键词： biomechanics contact pressure finite element analysis knee spacer

A rare cause of acute abdomen–Spontaneous rectus sheath hematoma

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian Pacific Journal of Tropical Biomedicine 2016年第10期6卷 892-895页

作者： Hock Chin chong Feng Yih Chai yew Eng Tan Sophia Si Ling Heng Siti Asilah Mohd Desa Department of Surgery Hospital Queen Elizabeth Department of Surgery Hospital Keningau

Spontaneous rectus sheath hematoma(SRSH) is a rare entity that mimics acute *** sheath hematoma is the accumulation of blood in rectus sheath due to muscle or epigastric vessel injury. However, SRSH without a trauma or anticoagulation is rare. It frequently mimics acute abdomen and it may lead to misdiagnosis and unnecessary laparotomy. In this article, we described two cases of SRSH with their diagnostic and therapeutic strategy. Both of our patients in report were neither consumed antiplatelet nor coagulopathy. They both had abdominal muscle straining before their symptoms presentation. We hypothesized that the SRSH may be induced by rectus muscle injury secondary to inappropriate straining or posture. To diagnose SRSH, clinical findings are important but radiologic imaging such as computed tomography, can be diagnostic. In expanding SRSH, percutaneous arterial embolization of epigastric artery is useful to secure the bleeding. If embolization is not feasible, surgical exploration hemostasis is curative. In non-expanding SRSH, it can be managed nonoperatively. SRSH is an important initial differential for acute abdomen. Radiologic imaging helps in *** SRSH can be managed conservatively with good outcome.

关键词： Rectus muscle injury Epigastric vessel Spontaneous Acute abdomen

Graphene Oxide Functionalized Optical Planar Waveguide for Water Content Measurement in Alcohol

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonic Sensors 2020年第3期10卷 215-222页

作者： Wenghong LIM Yuenkiat yap Choonkong LAI Wuyi chong Harith AHMAD Photonics Research Centre University of MalayaKuala Lumpur 50603Malaysia Heriot-Watt University Malaysia Putrajaya 62200Malaysia Department of Physics Faculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia

An abrupt change in optical transmission characteristic of a graphene oxide(GO)coated optical planar waveguide was *** observation was based on the peculiar characteristics of the graphene oxide film,namely its high transverse-electric polarized light propagation loss,highly selective permeability of water,and change in optical propagation characteristic in the presence of *** as-fabricated GO-coated optical waveguide showed a large polarization dependent loss of~32 dB in the C-band optical fiber communication window(1550 nm).The response of the proposed sensor was first tested by using *** a drop of water was applied onto the GO coating,the large polarization dependent loss was fully suppressed almost *** effect was reversible as the polarization dependent loss was restored after complete water evaporation from the GO ***-optical measurement of water content in alcohol was then demonstrated by using the GO-coated optical *** analyzing the drying profile of the water-alcohol mixture,water content in the range of 0.2 volume%-100 volume%could be *** measurements were carried out by using solution volume of 1.0μL *** all-optical sensing nature of the proposed sensor has potential applications in in-situ monitoring of water content in alcohol.

关键词： Graphene oxide water content alcohol solution optical waveguide

Fuzzy-based risk prioritization for a hydrogen refueling facility in Malaysia

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8期14卷 834-834页

作者： Hue-yee chong Mahidzal Dahari Hwa-jen yap Ying-tai Loong 1. Department of Mechanical Engineering Faculty of Engineering University Malaya Kuala Lumpur 50603 Malaysia

Hydrogen is starting to be mentioned as an alternative fuel to replace the fossil fuel in future transportation applications due to its characteristics of zero greenhouse gas emission and high energy efficiency. Before hydrogen fuel and its facilities can be introduced to the public, relevant safety issues and its hazards must be assessed in order to avoid any chance of injury or loss. While a traditional risk assessment has difficulty in prioritizing the risk of failure modes, this paper proposes a new fuzzy-based risk evaluation technique which uses fuzzy value to prioritize the risk of various scenarios. In this study, the final risk of each failure modes was prioritized by using the MATLAB fuzzy logic tool box with a combination of two assessments. The first assessment was concerned with the criteria which affected the actual probability of *** assessment considered the availability of the standard that was applied to prevent the likelihood of the scenario occurring. On the other hand, the second assessment was focused on evaluating the consequence of the failure by taking into account the availability of detection and the complexity of the failure rather than only the severity of the scenarios. A total of 87 failure scenarios were identified using failure modes and effect analysis(FMEA) procedures on hydrogen refueling station models. Fuzzy-based assessments were performed through risk prioritizing various failure scenarios with a fuzzy value(0 to 1) and risk level(low, medium, and high)while a traditional risk assessment approach presented the risks only in forms of level(low, medium, and/or high). Availability of the fuzzy value enabled further prioritizing on the risk results that fell in the same level of risk. This study concluded that fuzzy-based risk evaluation is able to further prioritize the decisions when compared with a traditional risk assessment method.

关键词：风险评估方法模糊值加氢站马来西亚设施优先级模糊逻辑工具箱故障模式

Rectal arterio-portal fistula: An unusual cause of persistent bleeding per rectum following a proximal spleno-renal shunt

维普期刊数据库

同方期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2013年第25期19卷 4087-4090页

作者： Hao Yun yap Ser Yee Lee Yaw Fui Alexander Chung Kiang Hiong Tay Albert Su-chong Low Choon Hua Thng Krishnakumar Madhavan Department of General Surgery Singapore General Hospital Department of Surgical Oncology National Cancer Centre Singapore Department of Diagnostic Radiology Singapore General Hospital Department of Oncologic Imaging National Cancer Centre Singapore Department of General Surgery National University Hospital Singapore

Gastrointestinal arterio-venous malformations are a known cause of gastrointestinal bleeding. We present a rare case of persistent rectal bleeding due to a rectal arterio-portal venous fistula in the setting of portal hypertension secondary to portal vein thrombosis. The portal hypertension was initially surgically treated with splenectomy and a proximal splenorenal shunt. However, rectal bleeding persisted even after surgery, presenting us with a diagnostic dilemma. The patient was re-evaluated with a computed tomography mesenteric angiogram which revealed a rectal arterio-portal fistula. Arterio-portal fistulas are a known but rare cause of portal hypertension, and possibly the underlying cause of continued rectal bleeding in this case. This was successfully treated using angiographic localizationand super-selective embolization of the rectal arterioportal venous fistula via the right internal iliac artery. The patient subsequently went on to have a full term pregnancy. Through this case report, we hope to high-light awareness of this unusual condition, discuss the diagnostic workup and our management approach.

关键词： Portal hypertension Esophageal varices Splenorenal shunt Arteriovenous malformations Portal vein thrombosis

An NLP-PCA Based Trading Strategy On Chinese Stock Market

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An NLP-PCA Based Trading Strategy On Chinese Stock Market