Finite element modelling of fixed-fixed end plate attached with vibration absorber

The present paper investigated the effect of the lightweight dynamic vibration absorber (LDVA) to reduce vibration of thin walled structure. The free and forced vibration response of a rectangular thin plate were performed using finite element method. Subsequently, the effects of attached single and dual LDVA were analysed in depth by using Ansys workbench 14.5. Results demonstrated that single LDVA attached at the centre of the plate succesfully attenuate vibration over the frequency range of 0- 600 Hz. By contrast, attached with dual LDVA only suppresses the resonance of the first second and fourth modes but not for third and fifth modes of thin walled structure. It was found that by simply increasing the weight of mass does not improve the vibration absorption over the entire frequency range. The study conclude that attached single LDVA are better than dual LDVA for vibration absorption of thin walled structure over the entire frequency range

Kaedah pengesanan automatik salur darah retina untuk imej digital fundus

Retinaialahsatulapisanmembranyangterletakpadabelakangmatayangboleh menggambarkankeseluruhanimejsalurdarahmenggunakankamerafundus.Struktur salur darahpadaretinamampumemberikanpetunjukpentinguntukmengenalpasti penyakit-penyakityangberkaitanmatadanbadan.Penyakitberkaitanoftalmikdapat dibuktikan denganperubahandiameter,sudutpercabangan,dankekerintinganpada salur darahretina.Olehyangdemikian,prosessaringandigalakkan,namunbegitu pemeriksaanyangdilakukanadalahsecaramanualdanmemerlukankepakaran,masa, dan kosyangtinggikeranaperalatanyangcanggih.Suatukaedahpengesanansalur darah secaraautomatikdiperlukanuntukmendapatkanimejkeseluruhanrangkaian salur darahyanglebihefektifberbandingpengesanansecaramanual.Hasilnya, keseluruhanstruktursalurdarahretinadapatdikesandengancepatdantepat.Walau bagaimanapun,pengesanansalurdarahmerupakanprosesyangrumitkeranasalur darah retinamempunyairangkaiansalurdarahyangrumitdengankepelbagaiansaiz dan lebar.Selainitu,imejretinamempunyaihingar,kontrayangrendah,danvariasi kecerahanpadaimejyangsamamenyebabkansukaruntukmembezakansalurdarah dan latarbelakang.Kehadiranlingkarancakeraoptikpadaimejretinaperludiuruskan denganbaikkeranaiamerupakankawasanpalingcerahdanpembuluhdarahberasal daripadapusatnya.Objektifutamakajianiniadalahbagimembangunkankaedah pengesananautomatiksalurdarahretinauntukimejdigitalfundusyangcekap.Ia mampu mengesansalurdarahsecaraoptimumbermuladaripadalingkarancakera optik sehinggahujungstruktursalurdarah.Penyelidikaninimencadangkantigafasa utama, iaitupra-pemprosesan,segmentasirangkaiansalurdarah,danpasca pemprosesan. Fasapra-pemprosesaninimenyediakanimejretinayanglebihbaik berbanding imejasaluntukmeningkatkankontraantarasalurdarahretinadanlatar belakang. Seterusnya,fasakeduamerupakansegmentasirangkaiansalurdarah menggunakan modelberasaskangarispengesanansudut.Kaedahinidapatmengesan piksel yangmewakilisalurdarahberdasarkanpencirianyangtelahdilakukan.Akhir sekali, fasayangketigaialahfasapascapemprosesanyangterbahagikepadadua,iaitu pengesananpikseldanpenuraspikselberkepentingan.Prosespengesanandijalankan denganmenggunakankaedahheuristikdanOtsuterubah.Prosesinimenukarkanimej skala kelabukepadaimejperduaanbagipengesanansalurdarahretina,manakalabagi proses penuraspikselberkepentingan,iaterbahagikepadapenyingkirantitiktidak berkepentingandanmemperbaikipikselyanghilang.Prosesinidijalankandengan menggunakan sudutpengagihanhistogramuntukmenentukantaburanyangdiperoleh daripadapikselkejiranan.Maklumatinikemudiannyadigunakanuntuk menyingkirkanpikselhingardanmenyambungkanpikselyanghilangyangjuga merupakansebahagiandaripadasalurdarah.Dapatankajiantelahmembuktikan kaedah yangdicadangkanberjayamengesansalurdarahdenganmenunjukkan peningkatan ketepatanbagipangkalandataDRIVE,HRF,danSTAREiaitu masing-masing 95.58%,93.40%,dan94.90%.Berbandingkaedahterdahuluyang hanyamencatatkanketepatansebanyak94.15%dan93.24%bagipangkalandata DRIVE danSTARE.Kesimpulannya,kajianinitelahberjayamembangunkankaedah pengesananautomatiksalurdarahretinauntukimejdigitalfundus

CFD Analysis on Different Filling Volume Capacity and Fluid Density for Flexitank Application

When it comes to the structural design of flexitanks used for freight transportation, liquid sloshing is a crucial subject of concern. However, with consideration of the flexitank shape, there is no specific capacity value that can be used as a guide for filling the liquid inside it. This phenomenon may cause a high-pressure impact on the flexitank, resulting in a leakage on the LLDPE package. One of the solutions to reduce the frequency of leaks occurred is to fill up the acceptable volume based on hydrodynamics performance. Therefore, the purpose of this paper is to investigate, using commercial computational fluid dynamics (CFD) software, the hydrodynamic performance of various flexitank filling volume capacities based on different liquid densities. This is evaluated by comparing the hydrodynamics study for filling capacities that are 1%, 2%, and 3% higher than the rated capacity for flexitanks that has been suggested by the Container Owner Association (COA). Due to the flexitanks thin walls, it is important to consider the impacts of fluid-structure interaction (FSI). To do this, a partitioned FSI approach is used by coupling the CFD and FEA solvers for this multiphysics issue. The main standpoint of FSI is that fluid forces are applied to structures, causing deformation. Hydrodynamic parameters such as structural deformation on flexitank, von-mises stress and von-mises strain were used to identify the suitable filling capacity for three different: water, latex, and crude palm oil, as these liquids are commonly used for flexitank. The results indicate that varying the liquid filling capacity affected the hydrodynamic performance of the flexitank. Following that, increasing the flexitank filled with water by 3% and increasing the flexitank filled with latex and CPO by 1% can lead to structural damage as it gives highest maximum value of total deformation for these capacities. Since the situation of the flexitank are in the braking condition, the highest elastic equivalent strain is occurred at the front-top of the flexitank structure

CFD Analysis of the Effect of Heat Distribution on Different Heating Pad Piping Arrangements for Flexitank Application

Variations in piping arrangements of heating pad for flexitank applications causes a difference in the time required to completely liquidise the liquid during the discharging process. As reference, a conventional heating pad took about 48 hours to heat up the flexitank. There are many commercials heating pad used in flexitank applications to facilitate the discharging process of liquid. However, there are still uncertainty or limitation reference regarding the heating pad for flexitank application. One of the solutions to minimize the time taken for discharging processis identify the finest piping arrangement of heating pad. Based on the previous study, piping arrangement plays an important role for performance of the heating pad heat distribution. Thus, this paper aims to study the thermal behaviour of different heating pad arrangement for flexitank application with references to commercial arrangement of floor heating pad based on various inlet pressure using computational fluid dynamics (CFD) simulation software. This study was done by comparing thermal analysis of three piping arrangement which is conventional arrangement, Serpentine arrangement, and Spiral arrangement. The geometry of heating pad was created using Computer-Aided Design (CAD) software, SolidWorks. The results have discussed some important components parameter that must be controlled for the system to function efficiently. These parameters include pressure distribution within the pipes, temperature distribution along the pipes, and piping arrangement patterns. The simulation results show that the Counterflow arrangement has a uniform temperature distribution between the inlet and outlet. The study concluded that counterflow arrangement generally the best arrangement among these three since the configuration allowing less pressure losses and better thermal distribution on flexitank and heating pad. This study is therefore useful for designers to explore more adequately the benefits of underfloor heating system on many applications

Proposed Framework for Assessing the Sustainability of Membrane Life Cycle

Developments in sustainability assessment tools are leading to an increased interest in sustainability assessment for products and services Several sustainability measurement tools and frameworks have been developed However most of these tools only focus on environmental considerations while some of the frameworks only focus on governmental progress In this paper a comprehensive framework for assessing sustainability is presented During framework development the Life Cycle Assessment (LCA) and fuzzy logic approach was applied LCA determined the sustainability parameters and estimated the potential environmental impact from the membrane product Next the fuzzy logic approach was applied to deal with the qualitative and quantitative data The proposed framework focuses on the evaluation of membrane products. However, the proposed framework can be adopted for other related products