130 research outputs found
Working and corporate performance: case of Malaysia.
Working capital always being disregard in financial decision making since it involve investment and financing in short term period. However, it is an important component in firm financial management decision. An optimal working capital management is expected to contribute positively to the creation of firm value. To reach optimal working capital management firm manager should control the trade off between profitability and liquidity accurately. The intention of this study is to examine the relationship between working capital management and firm profitability. Cash conversion cycle is used as measure of working capital management. This study is used panel data of 1628 firm-year for the period of 1996-2006 that consist of six different economic sectors which are listed in Bursa Malaysia. The coefficient results of Pooled OLS regression analysis provide a strong negative significant relationship between cash conversion cycle and firm profitability. This reveals that reducing cash conversion period results to profitability increase. Thus, in purpose to create shareholder value, firm manager should concern on shorten of cash conversion cycle till optimal level is achieved
Graphical User Interface (GUI) Controlled Mobile Robot
The advanced design and development of robotic technology in producing multi task are
increasingly. In this paper presents about designing and developing mobile robot model that can be
controlled using Graphical User Interface (GUI) via wireless protocol. This paper focuses on the
control mobile robot by using the GUI as navigation control and the user can get a view an image and
real time video on visual basic software. To address the problem of sired based control, XBee wireless
communication circuit was used in mobile robot through a computer command. The development of
this mobile robot consists of a chassis, a graphical user interface (GUI), XBee module, DC gear motor,
camera, track wheels and microcontroller type PIC18F4550. Differential driving method using L298
circuit was used to control movement of the robot. In mechanical design, the wheel track has been used
instead of conventional wheels to enable the robot to travel through different types of surfaces or rough
terrain. In addition, wireless cameras was attached to the robot as a system of monitoring function.
Finally, the robot will be designed to control wireless remote control that can control robots. Wireless
remote control allows the user of an environment that is unsafe or dangerous device and evades wires
or cables interfere with the movement of the robot
Particle Swarm Optimization (PSO) for Simulating Robot Movement on Two-Dimensional Space Based on Odor Sensing
Nowadays, researches in robotic field have grown increasingly. There are several types of research categories in the field of robotic. Recently, one of the famous research works recently was odor sensing. Within the technology that grows rapidly, this topic has become an interest among researchers. An odor sensing is not only applied in the medical field, but it has also been widely used in the industry. The gradient of concentration of an odor is measured by diluting some amount to reach the threshold of an odor. This paper focused on the implementation of the Particle Swarm Optimization (PSO) method based on odor sensing in two (2) dimensional space. However, it only discusses and focuses on applying in ideal condition. An ideal condition here means that there is no disturbance included in this simulation. The main idea of this paper was to observe how the particle agents make the movement based on concentration by applying the PSO method. The real sensor cannot be implemented in this simulation because the value of concentration is measured due to the distance from the particles agent to the goal of agents. Higher gradient concentration is shown at the shorter distance to the goal. The contributions in this paper are mainly to create an algorithms model by using Particle Swarm Optimization (PSO) to calculate the paths of movement of mobile robot until they reach the goals (source of odor) with respect to the concepts of odor sensing
Identification of the genomic mutation in Epha4rb-2J/rb-2J mice
The EphA4 receptor tyrosine kinase is involved in numerous cell-signalling activities during embryonic development. EphA4 has the ability to bind to both types of ephrin ligands, the ephrinAs and ephrinBs. The C57BL/6J-Epha4rb-2J/GrsrJ strain, denoted Epha4rb-2J/rb-2J, is a spontaneous mouse mutant that arose at The Jackson Laboratory. These mutants exhibited a synchronous hind limb locomotion defect or “hopping gait” phenotype, which is also characteristic of EphA4 null mice. Genetic complementation experiments suggested that Epha4rb-2J corresponds to an allele of EphA4, but details of the genomic defect in this mouse mutant are currently unavailable. We found a single base-pair deletion in exon 9 resulting in a frame shift mutation that subsequently resulted in a premature stop codon. Analysis of the predicted structure of the truncated protein suggests that both the kinase and sterile α motif (SAM) domains are absent. Definitive determination of genotype is needed for experimental studies of mice carrying the Epha4rb-2J allele, and we have also developed a method to ease detection of the mutation through RFLP. Eph-ephrin family members are reportedly expressed as numerous isoforms. Hence, delineation of the specific mutation in EphA4 in this strain is important for further functional studies, such as protein–protein interactions, immunostaining and gene compensatory studies, investigating the mechanism underlying the effects of altered function of Eph family of receptor tyrosine kinases on phenotype
The study of chromium oxide loading on platinum chromium oxide zirconia catalyst for n-dodecane and 1,4-diisopropylbenzene hydrocracking
Hydrocracking reaction is one of the major processes in petroleum refining. To date, the exploration of a suitable catalyst for hydrocracking reaction remains challenging. The presence of Pt loaded on Cr2O3-ZrO2 promotes the catalytic activity and stability of Cr2O3-ZrO2. While, zirconia has an interesting thermal and mechanical properties which make it as a support material. Therefore, in this study, platinum chromium oxide zirconia catalyst (Pt/Cr2O3-ZrO2) with different Cr2O3 loading (1, 4, 8, and 12 wt%) were prepared by impregnation method. The physical and chemical properties will be characterized by the XRD and FTIR analysis whereas catalytic testing will be analyzed by n-dodecane and 1,4-diisoproylbenzene hydrocracking. The XRD results showed that the peak intensity of the tetragonal phase of ZrO2 and bulk crystalline of Cr2O3 increased with the increase in the Cr2O3 loading from 1 to 12 wt%. The FTIR KBr analysis showed the presence of monoclinic and tetragonal phase of ZrO2 and none or only negligible amount of coke formed during the reaction. The 2,6-lutidine adsorbed FTIR analysis showed that six bands located at 1675, 1660, 1650, 1640, 1630 and 1625 cm-1 corresponding to the Bransted acid sites whereas the Lewis acid sites located at 1608, 1603, 1593, 1580, 1565 and 1560 cm-1. For n-dodecane and 1,4-diisoproylbenzene hydrocracking, all catalysts showed 100% conversion except for Pt/12Cr2O3-ZrO2. Hence, the presence of tetragonal phase and Lewis acid sites play an important role for catalytic activity of n-dodecane and 1,4-diisoproylbenzene hydrocracking
Design and characterization of flat lens antenna using aperture-coupled microstrip patches
A planar discrete lens antenna is a low profile, light weight and cost effective
solution to conventional and curved dielectric lenses. The basic theory of operation
of flat lens antenna unit cell is to collimate the feed spherical electromagnetic
incident wave into planar wavefront at the back of the aperture. Therefore, the array
unit cell must be designed to establish the required phase adjustment. Flat lens
antenna elements which are based on aperture-coupled microstrip patches are
presented. The lens contains 7×7 elements with a diameter of 71 mm and operates in
the X-band frequency range. The lens was experimentally validated and good
agreement between simulation and measurement results were obtained. The achieved
measured peak gain is 15.85 dB. This gives 6 dB gain enhancement for the system.
The antenna 1-dB gain bandwidth and power efficiency are 7.8% and 58%
respectively. A very good transmission phase shift of 340° is achieved with
transmission coefficient of better than 2.25 dB. In addition, the measured radiation
pattern results show that the antenna system has good symmetry between E and H
plane with a half-power beamwidth of 16.2° and 16.6° in E-plane and H-plane
respectively. Moreover, the proposed lens element employs a simple and less
fabrication complexity mechanism for phase shift correction. Finally, the obtained
results show that the proposed flat lens antenna is an attractive choice for the
applications of wireless airborne systems such as VSAT (Very Small Aperture
Terminal)
Effect of iridium loading on the formation of protonic acid sites over Ir/PtHZSM5
The Ir/Pt-HZSM5 with different iridium loading (0.3-1.0 wt%) was prepared by impregnation of iridium on Pt-HZSM5. The acidic properties of Ir/Pt- HZSM5 were studied by FTIR spectroscopy, while the activity of the catalysts was tested for n-pentane isomerization in a microcatalytic pulse reactor. The IR results of adsorbed 2,6-lutidine showed that all catalysts possessed strong Brönsted and Lewis acid sites in the outgassing at 473 K and below. When Ir/Pt-HZSM5 was heated in hydrogen, protonic acid sites were formed with concomitant decrease of Lewis acid sites. An increase in iridium loading continuously decreased the Lewis and Brönsted acid sites and inhibited the formation of protonic acid sites induced by hydrogen. The formation of protonic acid sites induced by hydrogen was also confirmed by the formation of electron detected by ESR spectroscopy. Additionally for n-pentane isomerization, an increase in iridium loading decreased the yield of isopentane due to the inhibition in the formation of protonic acid sites via hydrogen spillover phenomenon
Dynamin I phosphorylation by GSK3 controls activity-dependent bulk endocytosis of synaptic vesicles.
Glycogen synthase kinase 3 (GSK3) is a critical enzyme in neuronal physiology; however, it is not yet known whether it has any specific role in presynaptic function. We found that GSK3 phosphorylates a residue on the large GTPase dynamin I (Ser-774) both in vitro and in primary rat neuronal cultures. This was dependent on prior phosphorylation of Ser-778 by cyclin-dependent kinase 5. Using both acute inhibition with pharmacological antagonists and silencing of expression with short hairpin RNA, we found that GSK3 was specifically required for activity-dependent bulk endocytosis (ADBE) but not clathrin-mediated endocytosis. Moreover we found that the specific phosphorylation of Ser-774 on dynamin I by GSK3 was both necessary and sufficient for ADBE. These results demonstrate a presynaptic role for GSK3 and they indicate that a protein kinase signaling cascade prepares synaptic vesicles for retrieval during elevated neuronal activity
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