Palm oil mill effluent (POME) can be utilised directly as the sole substrate in the anaerobic fermentation of acetone-butanol-ethanol (ABE) and hydrogen by Clostridium acetobutylicum NClMB13357 in a submerged batch system. Effects of sedimented POME concentration and the initial culture pH on the production of ABE/H were studied. Sedimented POME with 90% v/v (POME90) at pH 5.8 is capable of producing 4.01 g/L ABE with acetone concentration at 1.97 g/L; butanol 1.74 g/L and ethanol 0.3 g/L. The highest concentration of butanol (1.86 g/L) was produced from a culture with initial pH 6.0. The production of hydrogen gas was proportioned to the concentration of POME. The highest hydrogen gas production was at pH 5.5 (31 mL). More than 50% (v/v) of hydrogen gas was produced at different pH except pH 4.5, when only 16% (v/v) or 5 mL of hydrogen was produced.
This study compares the mean blood lead concentration and its association with the mean neurobehavioral scores between 2 groups of workers. The exposed group was made up of 50 male workers from 2 battery manufacturÂing factories and the comparative group was made up of 40 male adminisÂtrative workers from a local university. The neurobehavioral test was carried out by using a modified World Health Organization Neurobehavioral Core Test Battery (NCTS). The NCTS consists of 7 tests, which are made up of the Benton Visual Retention Test, Digit Symbol, Digit Span, Pursuit Aiming Test, Reaction Time, Santa Ana Manual Dexterity Test and Trail Making Test. Blood samples were collected by venous puncture method. Blood lead concentrations were determined by the Graphite Furnace Atomic Absorption Spectrophotometer (GFAAS). The mean blood lead concentration of the exposed group (38.5 μg/dL) is higher than the comparative group (5.6 μg/dL). Results show significant difference in the mean blood lead concentration between the 2 groups (p<0.001). There are also significant differences in the mean scores of each NCTS test such as Benton Visual Retention Test (p = 0.001), Digit Span Test (p< 0.001), Digit Symbol Test(p< 0.001), Pursuit Aiming Test (p< 0.001), Reaction Time Test (p< 0.001), Santa Ana Manual Dexterity Test (p< 0.001), Trail Making Test (p<0.001) (p< 0.001) and the overall NCTS test (p<0.001) between the 2 groups. There are significant inverse correlation between blood lead concentrations with each and overall NCTS scores when the two groups are combined. There are significant inverse correlations between blood lead concentrations with educational years and income for all respondents. Statistical tests show that blood lead, age, years of formal education, total income, years of work, and ethnicity contributes to the overall NCTS scores. The GLM model shows that 56.9% of the mean NCTS scores are influenced by the variability in the contributing factors mentioned before.
The main purpose of this article is to introduce the technique of panel data analysis in econometrics modeling. The elasticity of labour, capital and economic of scale for twenty two food manufacturing firms covering from 1989 to 1993 is estimated using the Cobb-Douglas model. The three main techniques of panel data analysis discussed are least square dummy variables (LSDV), analysis of covariance (ANCOVA) and generalized least square (GLS). Ordinary Least Square (OLS) method is included as the basis of comparison.
A preliminary study was conducted to determine the presence and abundance of aquatic worms in Lake Chini ecosystem, Pahang (Gumum Sea). Samplings were conducted twice in 2000. Water quality analysis was conducted to determine the water quality of the lake at the sampling locations. Results showed that nutrient levels in the water body was low and values for other physical parameters such as temperature, pH and conductivity suggested that Gumum Sea in Lake Chini is free from pollution. According to Malaysian interim river classification (Department of Environment, Malaysia), Lake Chini falls within class I to III which indicates good water quality. Annelida was the most dominant phylum found in the study area, which comprise of two major families namely Naididae and Tubificidae. This phylum contributed about 59% of the total individuals sampled and the rests were Arthropoda and Plathyhelmintes. Naididae was the most dominat family and contributed over 98% of the toal population of aquatic worms present. Dero, Aulophorus, Pristina, Branchiodrilus and Ripistes were amongst the dominant genera and showed good adaptations to the pollution free ecosystem of Lake Chini.
Organostannum(IV) complexes derived from dicarboxylic acids have been successfully synthesised from triphenylstannum(IV) hydroxide (Ph3SnOH). The complexes were obtained by refluxing Ph3SnOH and the respective dicarboxylic acids (malonic, succinic, glutaric and adipic acids) using a Dean and Stark apparatus in the appropriate solvent. The free ligands and complexes were characterised by C, Hand Sn elemental analysis and spectroscopic methods such as infrared and nuclear magnetic resonance (1H, 13C NMR). Structure determination of triphenylstannum(IV) succinate, 2, showed that each dicarboxylate anion was bonded monodentatically to two triphenylstannum(IV) moieties. The geometry surrounding each stannum atom is close to a tetrahedron. Spectroscopic data obtained for all complexes were found to be similar and thus it may be concluded that all complexes have the same structure as 2.
An investigation of the effect of discharge of domestic sewage to rivers at Kajang (Jeluh and Langat River) and coastal waters at Negeri Sembilan (Port Dickson and Blue Lagoon) was carried out. The parameters studied focused on the characteristics of sewage such as organic content (biochemiÂcal oxygen demand, BOD and nutrients (dissolved phosphate, (PO4) and nitrate (NO)). The discharge of domestic sewage from oxidation ponds near Kajang has resulted in high levels of BOD and PO4 in river water, i.e. 1.9-5.1 and 0.15-2.03 mg/L respectively. The increase in BOD is correlated (r =0.77) with the decrease in the level of dissolved oxygen (DO) in the river water. In general. the effects of domestic sewage discharge on water quality is more obvious in the Jeluh and Langat rivers at Kajang when compared to the effect on marine water.
The unsteady mixed convection boundary layer flow near the forward stagnation point of a two-dimensional symmetric body prescribed by a uniform heat flux rate is studied in this paper. The main aim of the investigation is to identify situations in which dual solutions for the steady-state flow can be determined when the flow is opposing. It is also shown that there is a smooth transition from the unsteady initial flow (short time) to the final steady state flow (large time).
There are a lot of factors and conditions to be considered by tour and travel companies when designing quality product due to the fact that the product being sold is intangible and their ultimate goal is to sustain customers' loyalty. Fuzzy Logic Controller (FLC) has been observed to be compatible to this 'intangible' factor thus giving better result when compared to other methods. By using FLC, all communications are clear and have precise meaning.
Food contaminations are global problems that arise from industrial polluÂtion, agricultural practices, or from food preparation and storage processes. Food contamination may lead to adverse health effects and there is considÂerable effort on the part of governments and industry to minimize the level of contamination. A joint Food Contamination Monitoring and Assessment Programme under the UN Environmental Programme (UNEP) in conjunction with FAO and WHO was established in 1976. There are increases in numbers of 40 countries participating the programme in 1992. The main objectives of the Programme is to be informed about levels and trends of contamination in food, their contribution to total human exposure and significance with regard to public health and trade. The Programme have been concerned with levels of priority chemicals in foods of major dietary importance and a significant portion of the data concerns the estimated total dietary intake of those contaminants selected for further comparison with toxicologically available standards or tolerance intake levels.
Computer simulations is now becoming a common feature in many underÂgraduate physics textbook together with online supplements to supposedly enhance learning and understanding. Many questions arise as to how these computer simulations and online supplements are developed and is it a worthy investment on the part of the physics educators. In this paper we look at the ways how "Physlets" (Physics Applets) are developed for the purpose of the undergraduate physics curriculum. JAVA is the fastest-growing proÂgramming language today. In scientific programming, the JAVA language meets the need for a simpler object-oriented language than C++ but is not yet popular, useful and widely used in very large scale or number crunching physics simulations. One of JAVA applets’s strength is that it is device independent. And for physics learning, simulation applets embedded in World Wide Web pages allow interactive learning and students-programmable demonstrations. We will examine a few physics simulations using JAVA applets that we have developed. We also discuss the various different aspects of using JAVA applets in developing physics simulation. And finally we will look into the reasons as to why it is still not ready for use in intensive physics simulation.
This study comprised of physicochemical characterizations of starch extracted from Msp94 sweet potato tuber and production of high fructose glucose syrup from the starch. Msp94 sweet potato starch consisted of 7.3% water, 0.2% protein, 0.4% fat, 1.3% total ash, 94.8% total carbohydrates, 83.0% starch and 20.6% apparent amylose. The starch granules were spherical, polygonal and irregular in shapes with the size of 13-14 mm. Enzymatic hydrolysis of Msp94 sweet potato starch for 24,48, 72 hours, using a mixture of amyglucosidase-pullulanase enzymes during saccharification process, produced starch hydrolysates with dextrose equivalent (DE) of 94.8, 99.1, 99.3 respectively. This is followed by reduction in viscosity of the starch hydrolysates. Conversion of the Msp94 starch to percent of glucose after hydrolysing for 24,48 and 72 hours were 97.1%, 109.5% and 103.2%, respectively. Msp94 starch hydrolysates was then purified using three types of ion exchange resins and isomerized to highfructose syrup using glucose isomerase enzyme (Sweetzyme T). Thefructose content in isomerized Msp94 syrup was (43.8-46.5%) was comparable to the fructose content (44%) in commercial High Fructose Corn Syrup (HFCS) 42.
[Kajian ini merangkumi pencirian fizikokimia kanji yang diekstrak daripada ubi keledek Msp94 dan penghasilan sirap glukosa berfruktosa tinggi daripada kanji ini. Kanji ubi keledek Msp94 mengandungi 7.3% air, 0.2% protein, 0.4% lemak, 1.3% abu total, 94.8% karbohidrat total, 83.0% kanji dan 20.6% amilosa ketara. Purata saiz granul kanji adalah 13-14 mm, berbentuk bulat, poligon dan bentuk yang tidak tetap. Hidrolisis berenzim menggunakan gabungan enzim glukoamilase-pululanase dalam proses sakarifikasi, yang dijalankan ke atas kanji ubi keledek Msp94 selama 24, 48, 72 jam menghasilkan hidrolisat kanji dengan setaraan dekstrosa (DE) masing-masing pada 94.8, 99.1, 99.3. 1ni diikuti dengan kelikatan hidrolisat kanji yang semakin menurun. Penukaran kanji Msp94 kepada peratus glukosa adalah sebanyak 97.1 %, 109.5% dan 103.2% setelah dihidrolisis selama 24,48 dan 72 jam. Hidrolisat kanji Msp94 ditulenkan menggunakan tiga jenis resin penukar ion dan diisomer kepada sirap berfruktosa tinggi menggunakan enzim glukosa isomerase (Sweetzyme T). Kandungan fruktosa (43.8-46.5%) dalam sirap Msp94 yang telah diisomer adalah setara dengan kandunganfruktosa (44%) dalam sirap komersial, High Fructose Corn Syrup (HFCS) 42].
Several conventional staining techniques were employed to detect the life stages (in particular the spores) of Nosema bombycis from infected larvae of Plutella xylostella (diamondback moth, DBM) and the effects of the infection of N. bombycis on the larvae were studied. Larval instars 1, 2, 3 and 4 of the DBM were infected with four different spore concentrations (407150, 41420, 4260 and 420 spores/μl) accordingly by allowing them to feed on artificial diet previously inoculated with the respective spore concentrations. Larval tissues were processed for staining and the number of spores were counted and direct observations on the larvae were carried out at 24, 48 and 72 h post infection. The Gram s, Giemsa's, haematoxylin and trichrome staining techniques were more superior in detecting the spores, sporonts and meronts than the good Pasteurs. The main effect of the infection was mortality which was dose-dependent and that the younger ins tars were more susceptible to infection than the older ones. Spore concentrations of 407150, 41420 and 4260 spores/μl) caused death to the instars whereas the dose of 420 spores)μl was unable to kill the larval instars. The mortality rate of the younger instars was significantly higher (p<0.001) than the older ones. The LC50 and LC95 values of instar 1 and 2 were lower than those of the instar 3 and 4 after 48 and 72 h post infection. This showed that high spore concentrations were needed to kill the bigger size and matured instars. Histological studies on the infected larvae indicated that the infection caused severe cellular damages in fat tissues and the intestine leading to death. Results of this studies showed that life stages of N. bombycis in particular the spores were detected effectively using conventional staining techniques and the infectivity and the effects of the infection on the larval tissues of DBM were also established.
[Beberapa teknik pewarnaan biasa telah digunakan untuk mengesan peringkat hidup Nosema bombycis (khususnya spora) yang terdapat pada larva Plutella xylostella (rama-rama belakang intan, DBM) yang terjangkit begitujuga kesan jangkitan spora ini ke atas larva telah dikaji. Larva instar 1,2,3 dan 4 DBM yang bebas daripadajangkitan spora telah dijangkiti dengan empat kepekatan spora (407150, 41420, 4260 dan 420 spora/μl) secara berasingan dengan membiarkan larva ini memakan makanan buatan yang telah dicemari dengan kepekatan spora tersebut. Pemprosesan tisu dengan teknik pewarnaan, penentuan kepekatan spora daripada larva dan cerapan langsung telah dilakukan dalam tempoh 24, 48 dan 72 j selepas jangkitan. Didapati teknik pewarnaan Gram, Giemsa, hematoksilin dan trikrom lebih sesuai untuk mengesan spora, sporon dan meron daripada tisu larva yang terjangkit berbanding teknik 'good Pasteur'. Kesan utama jangkitan spora ialah kematian larva yang bergantung kepada kepekatan spora yang digunakan dan didapati ins tar yang lebih muda adalah lebih rentan terhadap jangkitan ini berbanding instar yang lebih matang. Kepekatan spora 407150, 41420 dan 4260 spora) μl boleh menyebabkan kematian manakala kepekatan spora terendah (420 spora/)1.l) tidak menyebabkan kematian. Kadar kematian instar yang lebih muda lebih tinggi (p<0.001 ) berbanding instar yang lebih matang. Nilai LC50 dan LC95 bagi instar 1 dan 2 lebih rendah berbanding instar 3 dan 4, selepas 48 dan 72 j jangkitan. lni menunjukkan bahawa kepekatan spora yang lebih tinggi diperlukan untuk membunuh instar yang bersaiz lebih besar dan lebih matang. Bilangan spora terendah diperolehi pada tempohjangkitan 24 j manakala bilangan spora tertinggi diperolehi pada tempoh jangkitan 72 j. Kajian histologi ke atas tisu larva terjangkit mendapati kerosakan terjadi pada tisu lemak dan usus yang menyebabkan kematian. Hasil kajian ini menunjukkan bahawa peringkat hidup N bombycis khususnya spora dapat dikesan dengan baik menerusi teknik pewarnaan yang biasa dan kebolehjangkitan parasit ini dan kesannya kepada larva DBM telah diketahui].
A laboratory study was carried out to study the microbiological quality of local honey and its potential as an antibacterial agent. Five local honeys namely, Belimbing, Gelam (Sample 1,2, and 3), Durian (Sample 1 and 2), Kelapa and Tualang were studied. Microbial colony count of each sample was determined using filtration method. Screening for antibacterial action against Staphylococcus aureus was carried out using agar diffusion method. The result showed that all samples had low colony counts ranging from 37 cfu/ml in Kelapa honey to 161 cfu/ml in Durian honey (Sample 2). All samples showed a very clear zone of inhibition for bacterial growth and there was significant difference (ANOVA, p<0.05) among the samples. Belimbing honey showed the biggest diameter (2.1cm) and Gelam honey – Sample 3 had the smallest (1.7 cm).
[Kajian ini dijalankan untuk mengkaji kualiti mikrobiologi madu tempatan dan keupayaannya sebagai agen antibakteria. Lima madu tempatan iaitu Belimbing, Gelam (Sampel 1, 2, dan 3), Durian (Sampel 1 dan 2), Kelapa dan Tualang telah dikaji. Bilangan koloni mikrob ditentukan menggunakan kaedah turasan. Sifat antibakteria terhadap Staphylococcus aureus pula dikaji menggunakan kaedah serapan agar. Keputusan menunjukkan bahawa semua sampel mempunyai bilangan koloni yang rendah sekitar 37 cfu/ml dalam madu Kelapa hingga 161 cfu/ml dalam madu Durian – Sampel 2. Semua sampel menunjukkan kesan rencatan pertumbuhan bakteria dan terdapat perbezaan ketara (ANOVA, p
Science has been defined as 'a way of knowing' which is, in certain respects, unlike other ways of knowing. While some forms of knowledge are highly personal and intuitive, the methods of science are designed to be as objective and impersonal as possible. Science has been referred to as 'public knowledge' because of its procedures for verification involve the whole of society. Science is also 'organised knowledge' because it is systematic and because it is supported by a group of social institutions without which it could not exist in its modern form. For many decades, Fensham, an internationally recognised science educator, has been one of the most important and consistent voices for the reform of science education based on his vision of a democratic and socially responsible science education for all, based on the fundamental premise that if society is to understand the world it must be educated in the principles of science upon which a sustainable world is premised. Thus, science has a real place in society and a social responsibility. From a chemistry perspective, this enabling science is perceived by society as irrelevant to the real world and the cause of many of the evils of the world. This paper addresses the pivotal role of chemistry both in science education and in the social responsibility of science campaign and simultaneously shows how chemistry is at the leading edge of sustainable science in both a scientific and social context.
Sains telah ditakrifkan sebagai 'suatu cara mengetahui'. Dalam ertikata tertentu, takrif ini berlainan dengan cara-cara mengetahui hal-hal lain. Sesetengah bentuk pengetahuan sangatlah tersendiri dan intuitif, namun kaedah sains direkabentuk sedemikian sehingga sejauh mungkin ia berobjektif dan tidak tersendiri. Sains telah dirujukkan sebagai 'pengetahuan awam' kerana prosedur pensahihannya melibatkan seluruh masyarakat. Sains juga merupakan 'pengetahuan yang tersusun' kerana ini bersistem dan kerana ia disokong oleh kumpulan institusi sosial. Tanpa sokongan ini sains tidak boleh wujud dalam bentuk modemnya. Selama beberapa dekad yang lalu, Fensham, seorang ahli pendidikan sains yang diiktiraf antarabangsa, merupakan seorang penggiat yang penting dan konsisten dalam menyuarakan pendapat ke arah perubahan pendidikan sains berdasarkan visinya, iaitu pendidikan sains untuk semua secara demokratik dan bertanggungjawab kepada masyarakat, berlandaskan kepada premis asas bahawa jika masyarakat hendak memahami dunia, maka ia mestilah dididik dalam prinsip-prinsip sains dengan prinsip-prinsip itu sendiri dijadikan premos bagi sebuah dunia mampan. Dengan demikian, sains mempunyai tempatnya yang sebenar dalam masyarakat dan mempunyai tanggungjawab kemasyarakatan. Dari perspektif kimia, masyarakat bertanggapan bahawa sains tersebut tidaklah relevan dalam dunia nyata dan merupakan penyebab kepada banyak keburukan dalam dunia ini. Kertas ini mengupas peranan pengimbangan bidang kimia dalam pendidikan sains dan dalam tanggungjawab sosial kempen sains dan sekali gus menunjukkan bahawa kimia adalah teraju bagi sains mampan dalam kedua-dua konteks sainstifik dan sosial.
Artificial Immune System (AIS) is an emerging field to the computer scientists and most of the recent works concerning AIS is in the area of Intrusion Detection System (IDS). AIS is based on human immune system. It is distributed in nature, deploys the adaptive learning and exercises complementary mechanism to defend human body from bacteria or foreign elements. Artificial Immune system is non-linear and adopts the biological concept in classifying self against the non-Âself cells. This paper discusses on the implementation of AIS using the Negative Selection Algorithm in classifying and recognizing patterns on digits (0 to 9). Data for every digit is extracted using moment invariants and is represented in 8 bit string. There are 10 sets of detectors generated and the complementary process between self and non-self is done using the XOR operator. The result for classification for a digit is based on the percentage matched. Higher percentage indicates that the test data is closed to the digit to be recognized.
[Sistem Kebal Buatan (SKB) adalah satu bidang biologi yang telah membuka lembaran baru kepada penyelidik sains komputer untuk menggabungkan konsep kebal buatan di dalam penyelidikan yang berkaitan seperti pencerobohan sistem keselamatan. SKB tabi'i adalah suatu sistem pembelajaran adaptif iaitu yang mempunyai ciri selari dan mekanisma pelengkap bagi pertahanan terhadap unsur asing atau bakteria yang memasuki tubuh badan manusia. SKB bertindak secara tak linear dan menggarap konsep biologi seperti pengelasan terhadap sel kendiri dan sel tak kendiri. Rencana ini memperihalkan pelaksanaan kaedah SKB menggunakan pendekatan pilihan negatif bagi proses pengelasan dan pengecaman corak terhadap digit sifar hingga digit sembilan. Data bagi setiap digit tersebut disari menggunakan kaedah momen tak ubah dan diwakili sebagai rentetan 8 bit. Setiap kelompok digit dikelaskan sebagai kendiri bagi menghasilkan data tak kendiri atau pengesan. Ini bermakna terdapat 10 kelas pengesan yang dijana, dan proses padanan antara data kendiri dan tak kendiri dilaksanakan menggunakan operasi XOR. Penjanaan keputusan bagi pengelasan untuk suatu digit dihitung berasaskan kepada nilai peratusan yang terhasil, iaitu nilai yang dijana merupakan nilai yang digunakan bagi mengecam digit yang wujud pada data ujian. Semakin besar nilai peratusan yang diperolehi, maka semakin hampir nilai tersebut kepada digit yang hendak dicam].
This study focused on the development and optimization of a hybrid material formed from sol-gel and chitosan which could be used as a chemical sensing material. It is hoped that this new matrix can overcome certain weaknesses in solÂgel and chitosan materials. Dip-coating technique was used to prepare the film on microscope glass slide which functioned as a solid support. For optimization purposes, thymol blue was chosen as a pH indicator and was entrapped in the film. The film was characterized using uv-Visible Spectrophotometer. Morphology studies of the surface of the film were carried out using Scanning Electron Microscope (SEM). Results indicated that the most suitable solgel: chitosan ratio for hybrid formation was 60:40 after considering the surface morphology of the film, leaching, response time and also the intensities of the spectrum. Besides that, the results also show that the pH indicator could be successfully entrapped inside the hybrid film and would still retain its chemical behavior just as in solution. The sensing material was found to have good repeatability when reacted with buffer solution and showed RSD values of 4.24 % and 5.96 % in buffer solution at pH 2.0 and pH 11.0, respectively. The entrapped indicator also showed good photo stability with RSD of 5.35 % for the duration of 8 hours. However; the reproducibility of the hybrid film was quite low with a RSD value of 18.40 % and 31.22 % at wavelength of 500 nm and 600 nm, respectively due to leaching.
[Penyelidikan ini difokuskan kepada pembangunan dan pengoptimuman bahan hibrid antara sol-gel dan kitosan untuk membentuk suatu matriks baru bagi penyediaan bahan penderia kimia yang dapat mengatasi kekurangan tertentu dalam bahan sol-gel danjuga kitosan. Teknik penyalutan celup telah digunakan untuk penyediaan filem nipis di atas penyokong slaid kaca mikroskop. Untuk tujuan pengoptimuman, timol biru dipilih sebagai penunjuk pH dan dipegunkan di dalam filem. Filem nipis dicirikan menggunakan Spektrofotometer UL-Nampak. Kajian morfologi ke atas permukaan filem pula dilakukan dengan menggunakan Mikroskop Imbasan Elektron (MIE). Keputusan yang diperolehi menunjukkan bahawa nisbah sol-gel:kitosan yang paling sesuai ialah 60:40 dengan mempertimbangkan dari segi morfologi permukaan filem, kelarutresapan, masa rangsangan dan juga keamatan spektrum. Selain itu, keputusan menunjukkan bahawa penunjuk pH berjaya dipegunkan dalam filem hibrid sol-gel-kitosan dan mampu mengekalkan sifat kimianya sebagaimana dalam larutan. Bahan penderia kimia ini didapati mempunyai kebolehulangan yang baik apabila bertindak dengan larutan penimbal dan menunjukkan nilai RSD yang baik iaitu 4.24% dan 5.96% dalam larutan penimbal pH 2.0 dan pH 11.0, masing-masingnya. Penunjuk pH terpegun turut menunjukkan kestabilan foto yang baik (RSD = 5.35%) untuk tempoh 8 jam. Walau bagaimanapun, kebolehasilan filem agak rendah dengan RSD yang bernilai 18.40% dan 31.22 % pada panjang gelombang 550 nm dan 600 nm masing-masing akibat daripada kelarut resapan].
Artificial neural network (ANN) was used in this study to determine water turbidity by using back propagation algorithm. Three wavelengths which represent reflectance intensity for eight standard samples were used as training input. The finding from the study shows that the trained network with number of epochs of 250,000 and learning rate of 0.001 gave the lowest sum of squared error (SSE) of 0.04. ANN was able to predict the turbidity of water based on the pattern recognition of the reflectance spectrum. The architecture of optimized ANN used in this study was 3:25:1. The average prediction error was 0.02.
[Jaringan neural tiruan (ANN) dengan lagoritma perambatan balik (BP) telah digunakan dalam kajian ini untuk menentukan kekeruhan air. Tiga panjang gelombang yang mewakili serapan bagi lapan sampel telah dipilih sebagai imput latihan. Hasil kajian menunjukkan bagi jaringan terlatih dengan bilangan ulangan latihan 250,000 dan kadar pembelajaran 0.001 telah memberikan nilai SSE yang terendah iaitu 0.04. Dalam kajian ini jaringan ANN didapati boleh menentu dan meramalkan nilai kekeruhan sample air berdasarkan corak serapan pantulan. Arkitektur yang sesuai bagi kajian ini adalah 3:25:1. Purata ralat ramalan adalah 0.02].
A study was carried out to determine the distribution of nutrient, chlorophyll-a and the physical properties of water at Setiu Wetland from May-October 2001. Ten sampling stations were selected to represent various locations within the study area. The analyses of dissolved nutrients and chlorophyll-a were carried out based on colorimetric methods while the physical parameters were measured in situ. The results indicated that pH values between 5.15-8.03, dissolved oxygen 4.89-6.85 mg/L, biological oxygen demand 0.04-1.80 mg/L and total suspended solids 1.3-19.7 mg/L. The concentrations of orthophosphate, total dissolved phosphate, nitrate, ammonia, total dissolved nitrogen and chlorophyll-a were in the range of 0.19-2.85 μg P/L, 1.06-25.81 μg P/L, 1.48-89.66 μg N/L. 6.0-125.7 μg N/L. 122.50-432.34 μg N/L and 0.03Â4.32 mg/L, respectively. In addition, the results obtained also suggest possible linkage between land use practices and deteriorations of water quality in the wetland area.
[Satu kajian telah dijalankan untuk menentukan taburan nutrien, klorofil-a dan sifat fizikal air di Tanah Bencah Setiu dari bulan Mei-Oktober 2001. Sepuluh stesen pensampelan telah dipilih untuk mewakili kawasan-kawasan yang berlainan di kawasan kajian. Analisis nutrien terlarut dan klorofil-a dijalankan berdasarkan kaedah kolorimetrik manakala parameter fizikal diukur secara in situ. Hasil kajian menunjukkan bahawa pH mempunyai nilai antara 5.15-8.03, oksigen terlarut 4.89-6.85 mg/L, permintaan oksigen biokimia 0.04-1.80 mg/L dan jumlah pepejal terampai 1.3-19.7 mg/L. Kepekatan ortofosfat, jumlah fosfat terlarut, nitrat, ammonia, jumlah nitrogen terlarut dan klorofil-a adalah masing-Âmasing dalam julat 0.19-2.85 μg P/L, 1.06-25.81 μg P/L, 1.48-89.66 μg N/L, 6.0-125.7 μg N/L, 122.50-432.34 μg N/L dan 0.03-4.32 mg/L. Disamping itu, keputusan yang didapati turut mencadangkan kemungkinan wujudnya hubungan antara kepelbagaian aktiviti guna tanah dan kemerosotan kualiti air di kawasan tanal: bencah].
The development of economy is closely related with the inflation rate of the country. Generally the inflation can be measured by the Consumer Price Index (CPl). The aim of this paper is using overlapping measure and cumulative measure to measure the inflation. In overall, these two methods are adequate for measuring the inflation. As a result, monthly measure is useful because it believe can give a perfect measure (since its sample is large) and can get rid of or smaller the error. Besides that, the value of the weighted CPl and the unweighted CPl are almost same. As the result, the unweighted of CPl is used to measure the inflation. The result of this two methods are satisfactory.
[Perkembangan sesuatu ekonomi adalah berkait rapat dengan kadar inflasi dalam sesebuah negara. Secara amnya, inflasi dapat diukur dengan Indeks Harga Pengguna (IHP). Tujuan kertas kerja ini adalah mengukur inflasi dengan menggunakan kaedah data bertindih dan kaedah kumulatif. Pada keseluruhannya kedua-dua kaedah tersebut adalah sesuai digunakan sebagai pengukuran inflasi. Oleh hal yang demikian, pengukuran secara bulanan digunakan kerana dipercayai bahawa ia dapat memberi ukuran yang lebih tepat (saiz sampel yang besar) dan dapat mengelakkan atau mengecilkan ralat berlaku. Selain itu, penggunaan IHP berpemberat dan IHP tanpa pemberat didapati mempunyai nilai yang hampir sama. Oleh itu, nilai IHP tanpa pemberat digunakan dalam pengukuran inflasi. Keputusan yang didapati daripada kedua-dua kaedah tersebut adalah memuaskan]
Amang are by-products obtained when tailings are processed into concentrated ores and other economical products such as monazite, (Ce, La, Th)PO4; zircon, ZrSiO4; ilmenite, FeTiO3; struverit; and xenotime, YPO4. Its could be extracted from amang for further usage. Tailings from these ores may have a significant potential to cause elevated radiation exposures. This project was carried out to measure the concentration of uranium and thorium in the waste and products produced after the processing of the amang and ilmenite ore. The concentration of uranium and thorium was determined using gamma ray spectrometer with HPGe detector. The concentration of uranium was determined by measuring the intensity of gamma ray emitted from its daughter nuclei 214Pb at 352 keV and 214Bi at 609 keV while the concentration of thorium was determined by measuring the intensity of gamma rays emitted from its daughter nuclei 228Ac at 911 keV and 208Tl at 583 keV. The concentration of uranium and thorium in ppm obtained in this study are as follows: raw amang (83 -383) and (174 - 1566); ilmenite (149 - 290) and (301- 575); monazite (2303 - 4070) and (9641 – 60061); zircon (963 - 1192) and (353 - 583) and waste (22 - 98) and (44 - 223) respectively. Rutile and iron oxide was obtained from ilmenite. The concentration of uranium and thorium in rutile was 50 and 72 ppm and from iron oxide was 336 and 379 ppm respectively. These values are considered high compare to normal sand and could pose danger to the surrounding.
[Amang adalah hasil sampingan yang diperoleh semasa pengekstrakan tahi timah kepada logam tulennya. Pelbagai hasil yang berekonomi seperti monazit, (Ce,La,Th)YPO4; zirkon, ZrSiO4; ilmenit, FeTiO3; struverit; dan xenotim, YPO4 boleh diekstrak daripada amang bagi kegunaan seterusnya. Pemprosesan tahi bijih ini berkeupayaan mendatangkan pendedahan sinaran yang tidak diingini. Kajian ini dijalankan untuk menentukan kandungan uranium dan torium yang terkandung dalam sisa dan hasil yang dikeluarkan semasa pemprosesan amang dan ilminit. Kepekatan kandungan uranium dan tarium ditentukan menggunakan spektrometer sinar gama dengan pengesan HPGe. Kandungan uranium ditentukan dengan mengukur keamatan sinar gama yang dipancarkan daripada nukleus anaknya, iaitu 214Pb pada tenaga 352 keY dan 214Bi pada tenaga 609 keY, manakala kandungan torium ditentukan dengan mengukur keamatan sinar gama yang dipancarkan oleh nukleus anaknya, iaitu 228Ac pada tenaga 911 keY dan 208Tl pada 583 keY. Kandungan uranium dan torium dalam ppm yang diperoleh daripada kajian ini masing-masing adalah seperti berikut: amang mentah (83 - 383) dan (174 -1566); ilmenit (149 - 290) dan (301 - 575); monazit (2303 - 4070) dan (9641 - 60061); zirkon (963 -1192) dan (353 -583) dan sisa (22 - 98) dan (44 - 223). Kandungan uranium dan torium dalam rutil masing-Âmasing ialah 50 and 72 ppm, manakala dalam ferum oksida ialah 336 dan 379 ppm. Nilai yang diperolehi ini adalah tinggi berbanding dengan pasir biasa semula jadi dan berpotensi mendatangkan kemudaratan kepada persekitaran].