Soft computing is an alternative to hard and classic math models especially when it comes to uncertain and incomplete data. This includes regression and relationship modeling of highly interrelated variables with applications in curve fitting, interpolation, classification, supervised learning, generalization, unsupervised learning and forecast. Fuzzy cognitive map (FCM) is a recurrent neural structure that encompasses all possible connections including relationships among inputs, inputs to outputs and feedbacks. This article examines a new methods for nonlinear multivariate regression using fuzzy cognitive map. The main contribution is the application of nested FCM structure to define edge weights in form of meaningful functions rather than crisp values. There are example cases in this article which serve as a platform to modelling even more complex engineering systems. The obtained results, analysis and comparison with similar techniques are included to show the robustness and accuracy of the developed method in multivariate regression, along with future lines of research.
Structural, magnetic and electrical characteristics of multiferroics (1-x)BaTiO3-xMgFe2O4 composites with weight fractions of x = 0.3, 0.5 and 0.7 are reported. MgFe2O4 powders were prepared using sol-gel auto combustion technique. It was combined with commercial BaTiO3 to form composites by using wet milling solid state reaction technique. Formation of tetragonal perovskite for the ferroelectric BaTiO3 and cubic spinel for the ferrimagnetic MgFe2O4 phases, were identified from the XRD pattern. The average grain size for each composite was about 0.5 μm. The M-H loop showed soft ferrimagnetic properties due to the presence of MgFe2O4 in the composites. The increment of the MgFe2O4 weight fraction increased the saturation magnetization and slightly changed the coercive field. The complex impedance plot can be represented by a parallel R and C circuit. Composite sample with x = 0.5 has the highest resistance with lowest capacitance and dielectric constant value at room temperature. The dielectric constant showed a very strong dispersion at low frequencies, due to the Maxwell-Wagner mechanism and a slight dispersion at higher frequencies. Based on the results obtained, all of the composite samples exhibited high dielectric constant and tangent loss at the low frequency range.
In this work, amorphous carbon nitride (a-CNx
) thin films were deposited by radio frequency (RF) plasma enhanced
chemical vapor deposition (RF-PECVD) technique. The RF power and gas mixture of methane (CH4
) and nitrogen (N2
)
flow was kept constant, while the electrode distance was varied from 1 to 6 cm. The effect of electrode distance on the
chemical bonding, morphology and humidity sensing responses of the films were investigated. Fourier transform infrared
spectroscopy (FTIR) studies showed a systematic change in the spectra and showed three main peaks namely the G
and D-peak, C≡N triple bonds and C-H/O-H groups. Uniform and porous morphology was observed for films deposited
at smallest distance followed by non-porous cubicle-like grain as electrode distance increased. Subsequently formation
of vertically aligned nanostructures apparent both from its surface and cross section images by increasing of electrode
distance to the fullest. The humidity sensing property has been studied by recording their resistance response to relative
humidity (RH) at room temperature. It was found that the resistance value decreases from 15.4 to 3.6 kΩ with the increase
in RH from 9 to 85%, with the highest sensitivity of 77% for film deposited at smallest distance of 1 cm.
Evaluating the satisfaction of caregivers is a highly subjective procedure and there is a need for a culturally appropriate, validated and sufficiently tested measurement tool to identify their needs in a clinical setting in order to improve the quality of care. FAMCARE is a self-report scale assessing patient/ caregivers’ satisfaction with outpatient care. This study evaluated the validity and internal consistency of a Malay-language version of the FAMCARE scale amongst Malaysian informal caregivers. A total of 45 Malaysian informal caregivers in the outpatient oncology clinic, Hospital Universiti Sains Malaysia completed the questionnaire. Responses were checked for construct validity (including exploratory factor analysis to check the factor structure of the scale) and internal reliability. The 20 items of the FAMCARE scale were subjected to principal axis factoring (PAF) using SPSS, starting with assessing suitability of the data for factor analysis. Correlation matrix showed the presence of many coefficients of 0.3 and above. The Kaiser–Mayer-Olkin value was 0.79 and the Barlett’s Test of sphericity was highly significant (p< .001). PAF showed the presence of four components with eigenvalues exceeding 1, explaining 60.8% of the cumulative variance. The items were loaded in four domains with satisfactory inter-factor correlations. The general FAMCARE questionnaire as a whole was found to have high internal reliability (Cronbach’s α = 0.93). The Malay-language version of the FAMCARE scale appeared as a valid and reliable tool for assessing informal caregiver’s satisfaction in outpatient settings, although it would be preferable to eliminate weak items which have low factor loading.
The first time report on the feeding ecology and food preference of mangrove horseshoe crab Carcinoscorpius rotundicauda (Latreille 1802) at their nesting grounds along the Pahang coast is given. Monthly sampling was carried out between March 2010 and February 2011 covering both monsoonal (March to October) and non-monsoonal (November to February) seasons. Major macrobenthic gut contents (bivalves, gastropods, crustaceans, polychaetes and miscellaneous food items including plant materials) were identified using microscopic examination. An electivity index (E1) was calculated for the frequent food items observed in the gut region of C. rotundicauda during monsoon and non-monsoon seasons. The EI was negative for crustaceans and positive for all the other food items including bivalves, gastropods, polychaetes and miscellaneous food items (which include insects, amphipods, Isopods, larval and juvenile stages of fishes, foraminifera and other Annelid worms). It is interesting to note that C. rotundicauda prefered less number of bivalves than polychaetes during non monsoon seasons but it was the reverse during monsoonal period. Male crabs intensely preyed on gastropods and female prefers polychaete worms during the peak mating/nesting season (June - August 2010). Seasonal variations in food composition showed that mollusks formed the main item especially gastropods. Unidentified organic matters in the gut content analysis of C. rotundicauda showed high preference towards plant materials. Gastro Somatic Index (GaSI) analysis showed that the feeding intensity of male crabs was higher during non-monsoon period while it was higher during monsoonal period in female crabs. In conclusion, the feeding ecology of mangrove horseshoe crabs were more similar to its closer and distant conspecifics. However, it was postulated that the higher preference of polychaete worms by the female C. rotundicauda during the peak mating season indicated its role in regulating the nesting behaviour.
The aim of this study to determine the numbers of CD34+ cells and total nucleated cell (TNC) in umbilical cord blood (UCB)
collected from pregnant mothers with gestational diabetes mellitus (GDM) and preeclampsia (PE), following statistical
analysis of both maternal and perinatal factors which affect UCB parameters. Most of studies explored the influence of
obstetric factors on the number of UCB cell collection and only a few looked at the effects on UCB haematopoietic stem
cell (UCB-HSC) of common disorders complicating pregnancy. A total of 112 UCB samples (32 PE, 42 GDM and 38 nondiseased) were collected. CD34+ cell and NC count were enumerated using FACS Calibur. The TNC and CD34+ cells were
significantly reduced in both PE and GDM groups as compared to the control group. The PE group shows significantly
lower birth weight and higher BP which led to a lower UCB volume and CD34+ count. Gestational age shows significant
correlation with nucleated cell count (NCC) and TNC. GDM group shows significantly lower systolic BP, NCC and TNC count,
including low placental weight and birth weight. Conclusively, some obstetrics factors have significant influences to the
numbers and quality of UCB-HSC in both PE and GDM groups, which could guide in the selection criteria for CB banking.
Biodiesel, one of the renewable energy sources has gained attention for decades as the alternative fuel due to its remarkable properties. However, there are several drawbacks from the industrial production of biodiesel such as the spike in the production cost, environmental issues related to the usage of homogeneous catalyst and profitability in long term. One of the solutions to eliminate the problem is by utilizing low cost starting material such as palm fatty acid distillate (PFAD). PFAD is a byproduct from the refining of crude palm oil and abundantly available. Esterification of PFAD to biodiesel will be much easier with the presence of heterogeneous acid catalyst. Most of acid catalyst preparation involves series of heating process using conventional method. In this study, microwave was utilized in catalyst preparation, significantly reducing the reaction time from conventional heating method. The catalyst produced was characterized using X-Ray Diffraction (XRD), Brunauer Emmet and Teller (BET), Scanning Electron Microscopy (SEM), Temperature-Programmed Desorption - Ammonia (TPD-NH3) and Fourier Transform Infrared (FTIR) while percentage yield and conversion of the PFAD were analysed by gas chromatography - flame ionization detector (GC-FID) and acid-base titration, respectively. It has been demonstrated that the percentage yield of biodiesel from the PFAD by employing sulfonated glucose acid catalyst (SGAC) reached 98.23% under the following conditions: molar ratio of methanol to PFAD of 10:1, catalyst loading of 2.5% and reaction temperature of 70oC. The microwave-assisted SGAC showed its potential to replace the SGAC produced via conventional heating method.
Biological fermentation of Rhizopus oryzae was introduced to extract cellulose nanofibre from durian skin fibre (DSF).
The diameter of the extracted durian skin nanofibre (DSNF) was in the range of 49-81 nm. The changes of chemical
composition of DSNF were clearly seen after evaluated via TAPPI standard test methods. Verification via Fourier transform
infrared (FTIR) confirmed the deduction of hemicelluloses and lignin in DSNF in the range of 1200 to 1000 cm-1. X-ray
diffraction (XRD) demonstrated increment in the crystallinity from 58.3 to 72.2% after biological fermentation. DSNF was
then incorporated into polylactic acid (PLA) via extrusion and injection moulding processes. The effect of 1-5 wt. % DSNF
content on PLA biocomposites was investigated for its mechanical and thermal properties. The presence of only 1 wt. %
improved the tensile and impact strength by 14.1 MPa and 33.1 kJ/m2
, respectively. The thermal properties of PLA-1DSNF
biocomposite also recorded higher thermal stability, glass transition temperature (Tg
), crystallization temperature (Tc
)
and melting temperature (Tm). Additionally, from the DMA, it was determined that PLA-1DSNF possessed lower storage
modulus and loss modulus, as well as low energy dissipation.
The Alur Lebey fault zone, which is paralled to part of Sungai Lebey, is exposed along the East-West Highway at km 221.5 to Kota Bharu. The outcrop is about 155 m wide on the east and 105 m wide on the west side of the road. Fault morphology can be recognised from the faceted hill spurs along the valley. The fault zone has been interpreted as a lithological contact between metavolcanic in the west and metaclastic in the east. The northern extension of the fault was interpreted as the contact between silicous pelite in the west, and chert and siliceous pelite in the east. Even though left lateral motion is exhibited within the zone, evidences of right lateral motion were also observed. On Landsat 3 image, a lineament in the direction of 355° representing the Alur Lebey fault zone could be traced for some 55 km from the East-West Highway to the middle of east Pattani River in Thailand. The outcrop at the East-West Highway comprises medium indurated mylonite containing lenses of quartz and tuff. Other than asymmetric lenses, quartz also occurs in the form of a comma, and pinch-and-swell structures. These forms of clasts are used to determine the sense of movements along the fault. In general, steeply to vertically dipping mylonite strikes towards the north. Fault planes with horizontal senses of motion cut the foliotion at an acute angle. Some of these fault planes are parallel to the foliation. There are also reverse fault planes with medium to gentle dips to the west. General motions of the fault were tOwards the east southeast. The mylonite foliation which strikes north contains evidences of both left and right lateral motions, whereas the northwest striking foliation exhibits left lateral motion. Several fault-associated folds plunging towards the north northwest, south southwest and east were observed in the fault zone. The combination of field observations and structural analysis are used to arrive at the interpretation on the history of the fault zone. Four systems of compressions (maximum principal stresses) can be deduced from the study. these are the north-northeast, east-southeast, east-southeast, and the youngest north-northeast directions. The oldest deformation is characterised by dextral movement along the mylonite zone. the zone contains asymmetric lenses of tuff and quartz striking 355° to 05°. The sinistral movement along mylonite fooliation striking 354° and 326° is the evidence of the east-southest compressive stress system. Both deformation episodes could represent aseismic faultings under fairly high confining pressure. However the recurrance of the east-southest stress system could have caused the sinistral movement along the northwest and north striking fault planes, the reverse faulting on south to southwest planes and the resulting drag folds. The dextral movement along the north and northwest planes is the youngest deformation episode. The final two episodes could represent brittle deformation resulting from the shallow position of the rock body at least along that particular fault segment.
Zon sesar Alur Lebey yang selari dengan sebahagian Sungai Lebey, tersingkap di km 221.5 dari Kota Bharu di lebuhraya Timur-Barat. Panjang singkapan keratan di timur jalan di sekitar 155m, manakala di barat jalan pula 105m. Morfologi sesar ditunjukkan oleh barisan susuh bukit beifaset di sepanjang lembah. Di lapangan dan di peta geologi, sesar ini ditafsirkan sebagai sempadan di antara metavolkano di baratnya dan metaklas di timurnya. Lanjutannya ke utara ditafsirkan bahawa sesar tersebut memotong sepanjang sempadan di antara pelit bersilika di barat dan rijang serta pelit bersilika di timur. Sungguhpun gerakan mendatar ke kiri terpamer dalam milonit, namun pergerakan mendatar ke kanan boleh dicerap dalam zon tersebut. Dalam area Lansat 3 bertarikh 10 Januari 1979 lineamen berjurus 355° yang mewakili zon sesar Alur Lebey dapat dikesan sepanjang 55 Ian dari Lebuhraya Timur-Barat hingga ke pertengahan bahagian timur Sungai Pattani di Thailand. Singkapan sesar tersebut terdiri daripada milonit separuh terluluhawa yang mengandungi kekanta kuarza dan tuf. Selain berbentuk kekanta, kuarza juga berbentuk koma, dan ramping-dan-ampul. Klas yang berbentuk tersebut digunakan untuk menentukan hala pergerakan dalam zon sesar. Umumnya milonit menjurus ke utara dengan kemiringannya euram hingga tegak. Satah-satah sesar mendatar memo tong foliasi milonit pada sudut tirus atauJdan ada pula yang selari dengannya. Selain sesar mendatar terdapat pula sesar songsang yang kemiringannya landai hingga sederhana ke barat. Gerakan umumnya menyongsang ke timur-tenggara. Foliasi milonit yang menjurus ke utara mengandungi tanda-tanda pergerakan ke kiri dan ke kanan, manakala foliasi yang menjurus ke baratlaut mengandungi hanya pergerakan mendatar ke kiri. Sebilangan lipatan yang berkait-rapat dengan sesar menunjam ke utara-baratlaut, selatan-baratdaya dan ke arah timur dieerap di dalam zon sesar tersebut. Gabungan eerapan lapangan dan analisis struktur akhirnya sampai kepada pentafsiran sejarah canggaan yang berlaku di dalam zon sesar tersebut. Empat sistem tegasan boleh disimpulkan. Sistem tegasan maksimum (mampatan) tersebut ialah .utara-timurlaut, timurÂtenggara, dan yang termuda utara-timurlaut. Canggaan tertua dicirikan oleh pergerakan dekstral di sepanjang zon milonit yang mengandungi kekanta tuf dan kuarza yang asimetri berjurus 355° hingga 05°. Pergerakan sinistral di sepanjang milonit yang berjurus 354° dan 326° merupakan bukti daripada sistem tegasan timur-tenggara. kedua-dua episod canggaan mungkin mewakili penyesaran aseismos yang berlaku dalam sekitaran tekanan mengepung yang tinggi. Namun demikian perulangan tindakan sistem tegasan timur-tenggara menyebabkan pergerakan sinistral di sepanjang satah sesar berjurus baratlaut dan utara, penyesaran songsang di atas satah berjurus selatan hingga baratdaya dan lipatan seret. Pergerakan dekstral di sepanjang satah berjurus utara dan baratdaya merupakan episod canggaan yang termuda. Dua episod yang terakhir mungkin mewakili canggan rapuh akibat daripada kedudukan cetek jasad batuan sekurang-kurangnya di sepanjang segmen sesar tersebut.
Generation of huge volumes of lignocellulosic biomass from agricultural sector is of concern due to its direct effects on the depletion of overall environmental quality. Conversion of biomass into solid biofuel through pyrolysis reaction has become one of the solutions to manage the abundance of biomass. Pyroligneous acid (PA) produced from the condensation of smoke generated during biomass carbonization process has the potential to be applied in various applications based on the diverse active chemical compounds present. In this study, PA obtained from palm kernel shell (PKS) was evaluated for antifungal activity and solid pineapple biomass (PB) was evaluated for antibacterial and plant growth promoter activities. Higher antifungal activity was determined for crude PA from PKS (PA-PKS) and dichloromethane-extract (DPA-PKS) with 0% coverage area when evaluated using rubber wood blocks against mold and blue sapstain after for 4 weeks of observation. This antifungal activity can be attributed to the presence of phenols and its major derivatives as suggested from the GC-MS and FTIR analysis. Concentrated PA from PB displayed good antibacterial capabilities with almost similar growth inhibition for Escherichia coli (13±1 to 20±1 mm) and Corynebacterium agropyri (20±1 mm). PA-PB also showed good potential as PGP where the addition of 2% (v/v) of PA-PB into the fertilizer for okra plant resulted in highest number of leaves and fruits while 4% (v/v) PA-PB managed to give highest plant height, longest root, heaviest fruits and biggest leaf diameter. Thus, this study successfully demonstrated the potential use of PA obtained from lignocelluosic biomass in various applications.
Dengue fever is considered as one of the most common mosquito borne diseases worldwide. Dengue outbreak detection can be very useful in terms of practical efforts to overcome the rapid spread of the disease by providing the knowledge to predict the next outbreak occurrence. Many studies have been conducted to model and predict dengue outbreak using different data mining techniques. This research aimed to identify the best features that lead to better predictive accuracy of dengue outbreaks using three different feature selection algorithms; particle swarm optimization (PSO), genetic algorithm (GA) and rank search (RS). Based on the selected features, three predictive modeling techniques (J48, DTNB and Naive Bayes) were applied for dengue outbreak detection. The dataset used in this research was obtained from the Public Health Department, Seremban, Negeri Sembilan, Malaysia. The experimental results showed that the predictive accuracy was improved by applying feature selection process before the predictive modeling process. The study also showed the set of features to represent dengue outbreak detection for Malaysian health agencies.
The extraction of pectin from dragon fruit (Hylocereus polyrhizus) peels under three different extraction conditions was identified as an alternative source of commercial pectin. In this work, dried alcohol-insoluble residues (AIR) of dragon fruit peels were treated separately with 0.25% ammonium oxalate/oxalic acid at a pH of 4.6 at 85oC; 0.03 M HCl at a pH of 1.5 at 85oC; and de-ionized water at 75oC. The pectin obtained from these methods was compared in terms of yield, physicochemical properties and chemical structure. Fourier Transform Infrared Spectroscopy (FTIR) was used in the identification of dragon fruit pectins. The results showed that the pectin yield (14.96-20.14% based on dry weight), moisture content (11.13-11.33%), ash content (6.88-11.55%), equivalent weight (475.64-713.99), methoxyl content (2.98-4.34%), anhydrouronic acid (45.25-52.45%) and the degree of esterification (31.05-46.96%) varied significantly (p < 0.05) with the various extraction conditions used. Pectin extracted with ammonium oxalate gave the highest yield of pectin, with high purity and low ash content. Based on the value of methoxyl content and the degree of esterification, dragon fruit pectin can be categorized as low-methoxyl pectin.
The effect of copper addition on martensitic structure and reversion from martensite to austenite behaviours upon heating were investigated to clarify mechanism of grain refinement of austenite in Fe-8wt.%Ni-Cu alloys. Upon water-quenching, the alloys underwent a martensitic transformation that exhibited a typical lath-martensitic structure. It was found that prior-austenite grain and martensite-packet sizes were refined with increasing copper content. The grain refinement was not due to a decrease of grain growth rate of the austenite. However, it was found that nucleation rate of the austenite on reversion was increased by the copper addition. In Fe-8wt.%Ni alloy heated in (austenite+ferrite) region, reversed austenite grains were formed at high angle boundaries such as prior austenite grain boundary and packet boundary. On the other hand, TEM observation of the Fe-8wt.%Ni-3wt.%Cu alloy revealed that fine copper particles precipitated within the martensitic structure and the reversed austenite grains also formed within lath-structures and lath boundary. It means that the copper addition promoted formation of the reversed austenite within martensitic matrix and resulted in the grain refinement of the prior-austenite in Fe-8wt.%Ni-Cu alloy.
Effects of different incubation methods on crawling and swimming ability of post-emergence green sea turtle (Chelonia mydas) hatchlings at Cherating (Kuantan, Pahang) and Chagar Hutang (Pulau Redang, Terengganu) Turtle Sanctuary were analysed during nesting season in 2009. Mean crawling speed of hatchlings incubated in styrofoam box, beach hatchery and in situ were at 0.042±0.008, 0.136±0.026 and 0.143±0.045 m/s, respectively. Crawling performance of hatclings from styrofoam box can be improved by keeping them for at least 48 h after their emergence. For swimming performance, all types of incubation methods showed significant differences in mean power-stroke rate during their early swimming effort ranging at 93-114 strokes/min. However, no correlation was found between morphological characteristics of hatchlings and swimming performance. The results from this study may give different perspective in evaluating hatchling production, which is in terms of hatchling morphological characteristics and their locomotor performance.
In this study, zinc oxide (ZnO) nanorod arrays were synthesized using a simple hydrothermal reaction on a ZnO seeds/
ITO substrate and applied for the fabrication of enzymatic glucose sensor. ZnO nanorod matrix provided a favourable
environment for the immobilization of glucose oxidase (GOx) and introduced a shuttling way for electronic communication
between GOx and electrode. The performance of different aspect ratio of ZnO nanorods that was produced by varying
hydrothermal reaction time was studied. The aspect ratio of ZnO influenced the GOx enzyme immobilization. The
morphology and structure of prepared ZnO nanorods were characterized by employing scanning electron microscopy
(SEM), and X-ray powder diffraction (XRD). Electrochemical measurements of the sensor showed a reproducible sensitivity
of 2.06 μA/cm2
mM for ZnO matrix grown for 4 h with the aspect ratio of 8.0.
The purpose of this study is to determine the visual status and effectiveness of low vision devices among visually impaired school children. One hundred and thirteen students from the special education schools took part in this study. Distance and near visual acuity were measured both with and without low vision devices. Students needing further assessment were referred to the Low Vision Clinic (LVC) Universiti Kebangsaan Malaysia. On presentation, 31% of the students were catagorised as low vision with distance acuity between 6/18 and 6/95 whereas 67% were blind. 2% were found to have distance acuity better than 6/18. The range of near visual acuity of these students was between N4 and N64. Low vision devices such as hand held magnifier, stand magnifier and telescope, were owned by only 17% of low vision students. This study showed that 85% of the students that were referred to the LVC benefited from low vision devices. Access to visual examinations and eye care for students with needs to be provided so that these students can be identified early and suitable low vision devices prescribed. This study emphasises the importance of the role played by parents, teachers and optometrists in the management of vision impairment in school children so that their visual impairment can be rehabilitated effectively.
Keywords: Low vision assessment; low vision devices
Padanan lengkung merupakan salah satu masalah yang sering menjadi perhatian terutamanya dalam bidang kejuruteraan balikan sejak dua dekad lepas. Dalam kajian ini, suatu kaedah dan algoritma baru telah direka untuk melakar semula garisan fon Arab. Evolusi pembezaan (EP) telah digunakan untuk mencari penyelesaian yang optimum bagi masalah padanan lengkung dengan menggunakan lengkung Bézier kuartik. Proses padanan lengkung ini merangkumi langkah berikut: Pengekstrakan sempadan dan pengesanan bucu, pemparameteran panjang rentas dan akhir sekali padanan lengkung. Bagi memastikan nilai titik kawalan yang dipilih mampu menghasilkan lengkung berparameter yang menyerupai lengkung asal fon tersebut, jumlah ralat kuasa dua (JRKD) digunakan untuk menghitung perbezaan antara lengkung asal imej dan lengkung berparameter.
Pembinaan semula lengkung banyak digunakan dalam kejuruteraan balikan untuk menghasilkan lengkung. Dalam kajian ini, evolusi pembezaan (EP) digunakan untuk mencari nilai titik kawalan yang optimum bagi lengkung Bézier kubik. Nilai titik kawalan yang diperoleh akan digunakan dalam persamaan lengkung Bézier kubik dan jumlah ralat antara imej sebenar dengan lengkung parametrik yang baru dihitung dengan menggunakan jumlah ralat kuasa dua (JRKD).
This paper considers the problem of outlier detection in bilinear time series data with special focus on BL(1,0,1,1) and BL(1,1,1,1) models. In the previous study, the formulations of effect of innovational outlier on the observations and residuals from the process had been developed and the corresponding least squares estimator of outlier effect had been derived. Consequently, an outlier detection procedure employing bootstrap-based procedure to estimate the variance of the estimator had been proposed. In this paper, we proposed to use the mean absolute deviance and trimmed mean formula to estimate the variance to improve the performances of the procedure. Via simulation, we showed that the procedure based on the trimmed mean formula has successfully improved the performance of the procedure.
In this paper a class of capital investment problem is considered within the context of mathematical programming. The usual and commonly used approach is presented upon the basis of the next present value criterion, and a branch and bound method is discussed for a model under extended assumptions.
Dalam kertas ini satu kelas masalah pelaburan kapital difikirkan di dalam konteks pengaturcaraan matematik. Pendekatan biasa dan selalu digunakan, dikemukakan berasaskan kriterium Nilai Semasa Berikut dan satu kaedah bercabang dan terbatas dibincangkan untuk satu model di bawah anggapan yang diperluaskan.