Statistical analysis of freshwater parameters monitored at different temporal resolutions

Nowadays, it is of great importance in ecological and environmental studies to investigate some prominent features in environmental determinants using appropriate statistical approaches. The initial motivation of this work was provided by the enthusiasm of the limnologist, biologist and statistician, interested in exploring and investigating certain features of time series data at different temporal resolutions to environmental parameters in freshwater. This thesis introduces a variety of statistical techniques which are used to provide sufficient information on the features of interest in the environmental variables in freshwater. Chapter 1 gives the background of the work, explores the details of the locations of the case studies, presents several statistical and ecological issues and outlines the aims and objectives of the thesis. Chapter 2 provides a review of some commonly used statistical modelling approaches to model trend and seasonality. All the modelling approaches are then applied to low temporal resolution (monthly data) of temperature and chlorophyll measurements from 1987-2005 for the north and south basins of Loch Lomond, Scotland. An investigation into the influence of temperature and nutrients on the variability of log chlorophyll is also carried out. Chapter 3 extends the modelling for temperature in Chapter 2 with the use of a mixed-effects model with different error structures for temperature data at a moderate temporal resolution (1 and 3 hourly data) in the north, mid and south basins. Three approaches are proposed to estimate the positions of a sharp change in gradient of temperature (thermocline) in deeper basins, using the maximum relative rate of change, changepoint regression and derivatives of a smooth curve. Chapter 4 investigates several features in semi-continuous environmental variables (15 and 30 minutes data). The temporal pattern of temperature, pH, conductivity and barometric pressure, and the evidence of similarity of the signals of pH and conductivity is determined, using wavelets. The time taken for pH and conductivity to return to `baseline levels' (recovery period) following extreme discharge is determined for different thresholds of `extreme discharge' for the Rivers Charr and Drumtee Burn, Scotland and models for the recovery period are proposed and fitted. Model validation is carried out for the River Charr and the occurrence of clusters of extreme discharge for both rivers is investigated using the extremal index. Chapter 5 summarises the main findings within this thesis and several potential areas for future work are suggested

Identifying the monotonic trend in climate change parameter in Kluang and Senai, Johor, Malaysia

Presently, climate change plays an important role as it gives a serious impact to the living things on earth. Analyzing the trend of climate change is very important in identifying the pattern of changes because it can give an initial overview for future analysis. In this study, trend analysis was carried out to study the pattern of changes for five climate change parameters, such as total amount of monthly precipitation (mm), monthly average temperature (°C), monthly average global radiation (MJm–2), monthly average wind speed (m/s) and monthly average humidity (%) during the period of 1974 to 2010. Comparisons were made between two research stations, which were the Senai International Airport and Kluang Meteorological Stations. In this study, the Mann-Kendall trend test and Sen’s slope estimator test were used to identify the monotonic trend for these climate change parameters. As a result of this analysis, the precipitations showed no trend for both locations and the radiation showed no trend in Kluang from both analyses. Meanwhile, other parameters in Senai and Kluang showed a monotonic trend, according to the Tau value (Z) and the Sen’s slope value. The temperature shows a positive trend for both locations

Religiositi sebagai faktor mediasi tingkah laku kerja muslim

Sorotan literatur mendapati bahawa tiada perkaitan yang jelas dan empirikal antara religiositi, personaliti dan tingkah laku kerja Muslim. Kajian ini bertujuan untuk mengkaji secara empirikal hubungan antara personaliti, religiositi dan tingkah laku kerja dalam kalangan pentadbir Muslim di universiti awam Malaysia. Tiga instrument digunakan dalam pengukuran pembolehubah kajian iaitu NEO Five Factor Inventory (NEO FFI), Muslim Religiosity Personality Inventory (MRPI) dan Inventori Tingkah Laku Kerja Muslim (ITKM). Responden terdiri daripada 228 orang pentadbir dari lima institusi pengajian tinggi awam tempatan. Analisis korelasi, regresi dan mediasi digunakan untuk mengenalpasti hubungan antara ketiga-tiga pembolehubah tersebut. Analisis korelasi antara ketiga-tiga pembolehubah mendapati bahawa hanya tret personaliti Neuroticism (r = -.21), Extraversion (r = .19) dan Conscientiousness (r = .22) mempunyai hubungan yang signifikan dengan religiositi. Ketiga-tiga tret ini juga mempunyai hubungan yang signifikan dengan Tingkah Laku Kerja Muslim. Tret Neuroticism (r = -.32), Extraversion (r = .29) dan Conscientiousness (r = .22) juga mempunyai hubungan yang signifikan dengan tingkah laku kerja Muslim. Analisis regresi menunjukkan bahawa tret Neuroticism, Extraversion, dan religiositi adalah faktor peramal kepada tingkah laku kerja Muslim secara signifikan [F(3,224) = 22.31, p < .05]. Analisis mediasi menunjukkan religiositi menjadi separa-perantara secara signifikan antara tret Neuroticism dengan tingkah laku kerja Muslim (B = -0.29; CI = -0.65 hingga -0.85) dan antara tret Extraversion dengan tingkah laku kerja Muslim (B = 0.28; CI = 0.08 hingga 0.58). Kajian ini mengesahkan peranan religiositi sebagai perantara kepada personaliti dan tingkah laku kerja Muslim serta menunjukkan kepentingan religiositi dalam mencorakkan tingkah laku kerja dalam kalangan pentadbir Muslim di universiti-universiti awam

Fuzzification of quantitative data to predict tumour size of colorectal cancer

Regression analysis has become more popular among researchers as a standard tool in analyzing data. This paper used fuzzy linear regression model (FLRM) to predict tumour size of colorectal cancer (CRC) data in Malaysia. 180 patients with colorectal cancer received treatment in hospital were recorded by nurses and doctors. Based on the patient records, a triangular fuzzy data will be built toward the size of the tumour. Mean square error (MSE) and root mean square error (RMSE) will be measured as a part of the process for predicting the size of the tumour. The degree of fitting adjusted is set between 0 and 1 in order to find the least error. It was found that the combination of FLRM model with fuzzy data provided a better prediction compared to the FLRM model alone. Hence, this study concluded that the tumour size is directly proportional to several factors such as gender, ethnic, icd 10, TNM staging, diabetes mellitus, Crohn’s disease

On linear and oblong leaves shape model

The aim of this paper is to develop and represent the overall linear and oblong leaves shape model for a given botanical textual description. For this purpose, the B-spline generative shape method (GSM) was used where the tip, side and the base of the linear and oblong leaves were assembled. Using the GSM and the leaf shape synthesis system, the tip and the base will be automatically generated preserving 2C continuity to ensure a reasonable shape in proportion. Expert botanists were referred to assess the drawing results. The findings show that the use of GSM produced good result except for some cases where the drawing produced minor visual error. As a conclusion, the GSM is a very practical way to model the linear and the oblong leaf shape. As the implication, both the GSM and the system allow the botanists to readily see a picture which might have been hard to visualize before

Tarikan terhadap buku Indie dalam kalangan pembaca muda di Malaysia

Buku genre Indie telah mendapat tempat dalam kalangan pembaca muda, khususnya generasi Z. Jualan buku Indie pada tahun 2013 dan 2015 telah menunjukkan penguasaan mereka dalam carta penjualan buku tempatan dan ini bukan sekadar mencabar tetapi mengalahkan genre penulisan arus perdana. Minat pembaca dengan genre penulisan ini dikaitkan dengan keunikan pendekatan penulisannya. Justeru, kajian ini mengkaji faktor tarikan terhadap keunikan penulisan buku Indie dalam kalangan pembaca muda di Malaysia. Kajian ini menggunakan reka bentuk tinjauan melalui pengedaran borang soal selidik sebagai kaedah pengumpulan data. Borang soal selidik telah diedarkan kepada 100 orang responden menggunakan persampelan bertujuan. Sampel responden dipilih dalam kalangan kelompok netizen pada peringkat remaja dan awal belia sebagai kumpulan generasi Z. Hasil kajian mendapati terdapat lima faktor yang menjadi tarikan kepada pembaca untuk membeli dan membaca buku berkenaan iaitu dari sudut tajuk, kulit buku, olahan isi kandungan, mesej dan grafik serta peranan media baharu. Buku Fixi Sdn. Bhd. dan Dubook Press mencatatkan penerbit buku Indie yang paling diminati dan menjadi pilihan dalam kalangan pembaca muda

Pemerkasaan pendakwah mualaf dengan ilmu kecerdasan spiritual di MUIP

Kajian ini bertujuan mengenalpasti pengetahuan, pengalaman pembelajaran dan keperluan modul ilmu kecerdasan spiritual (kerohanian) dalam kalangan pendakwah mualaf lantikan Majlis Ugama Islam dan Adat Resam Melayu Pahang (MUIP). Kaedah kajian kualitatif menggunakan instrumen temubual digunakan untuk mengumpul data daripada peserta kajian. Instrumen temubual telah dibina berdasarkan objektif kajian dan telah melalui proses pengesahan oleh pakar sebelum digunakan dalam kajian sebenar. Peserta kajian dipilih secara rawak daripada senarai pendakwah mualaf yang mendaftar dan dilantik oleh MUIP. Mereka terdiri daripada pelbagai bangsa iaitu Orang Asli, Cina dan India. Temubual dilaksanakan secara bersemuka dan dalam talian bergantung faktor lokasi dan masa responden. Semua rakaman temubual diterjemahkan ke bentuk teks berbantukan aplikasi Inscribe. Jawapan responden dianalisa dan dikategorikan mengikut tema. Dapatan kajian menunjukkan 60% responden mempunyai tahap pengetahuan ilmu kecerdasan spiritual samaada pada tahap rendah dan sederhana. Sebahagian responden (50%) menyatakan mereka mendapat pendedahan kepada ilmu kecerdasan spiritual secara formal dan sebahagian lagi secara tidak formal. Majoriti responden (80%) menyatakan mereka memerlukan ilmu kecerdasan spiritual untuk memberi kekuatan dalaman dan memantapkan usaha dakwah mereka. Oleh itu, terdapat keperluan untuk membina Modul Ilmu Kecerdasan Spiritual dan menyampaikan ilmu tersebut secara lebih formal dan terancang kepada pendakwah mualaf dan seterusnya membantu memperkasakan lagi usaha dakwah di Malaysia

Glycerol degradation in the absence of external hydrogen gas by using waste eggshell as heterogeneous catalyst = Degradasi gliserol tanpa kehadiran hidrogen luaran dengan menggunakan sisa kulit telur sebagai mangkin heterogen

The demand of biodiesel production nowadays is increasing every day. However, the booming of biodiesel demand resulted in the increase of glycerol production as a major by-product. Although glycerol could serve in various industries, the demand and usage are still limited. Therefore, an alternative method was proposed in this research in order to convert glycerol into more value-added chemicals such as methanol (MeOH), propanol (1-PrOH), and 1,2-propanediol (1,2-PDO) through a new low cost and simple approach which is the reflux technique in the absence of external hydrogen gas. Due to the concern of global food waste issues, calcium oxide (CaO) catalyst derived from waste eggshells is utilized as a possible heterogeneous catalyst. This preliminary research studied the influence of reaction temperature and reaction time whereas catalyst weight and glycerol concentration were fixed as independent variables. Overall, the three chemicals were successfully synthesized with different optimum conditions. The formation of 1,2-PDO is more preferred at lower temperature (130 °C and 5 hours) with glycerol conversion and selectivity of 53.70% and 64.76%, respectively. However, the formation of MeOH and 1-PrOH are preferred at higher temperature. The formation of 1-PrOH (170 °C and 5 hours) resulted in glycerol conversion and selectivity of 81.64% and 70.85%, respectively. Meanwhile, the best condition in the formation of MeOH is at 190 °C and 7 hours reaction time with glycerol conversion and selectivity of 65.8 % and 46.44%, respectively. ****************************************************************************** Permintaan pengeluaran biodiesel semakin meningkat setiap hari. Fungsi biodiesel itu sendiri sebagai bahan api alternatif untuk menggantikan penggunaan bahan api fosil adalah salah satu teknik terbaik untuk mengurangkan pembebasan gas karbon dioksida (CO2 ) yang dikeluarkan di atmosfera. Walau bagaimanapun, permintaan biodiesel yang tinggi menyebabkan peningkatan penghasilan gliserol sebagai produk sampingan utama. Walaupun gliserol boleh digunakan dalam pelbagai industri, permintaan dan penggunaannya masih terhad. Oleh itu, satu alternatif telah diambil dalam penyelidikan ini untuk menukar gliserol menjadi bahan kimia yang lebih bernilai seperti metanol (MeOH), propanol (PrOH) dan 1,2-propanediol (1,2-PDO) melalui pendekatan baharu yang lebih murah dan lebih mudah iaitu dengan menggunakan teknik refluks. Penukaran gliserol juga dilakukan tanpa kehadiran gas hidrogen luaran. Dengan mengambil kira mengenai isu kenaikan sisa makanan global, mangkin kalsium oksida (CaO) yang diperoleh daripada sisa kulit telur telah digunakan sebagai mangkin heterogen. Penyelidikan awal ini bertumpu mengkaji parameter pengaruh suhu tindak balas dan masa tindak balas, manakala berat mangkin dan kepekatan gliserol dijadikan sebagai pemboleh ubah tidak bersandar. Secara keseluruhan, ketiga-tiga bahan kimia telah berjaya disintesis dengan keadaan optimum yang berbeza. Pembentukan 1,2-PDO lebih baik pada suhu yang rendah (130 °C dan 5 jam) dengan penukaran gliserol dan selektiviti pada 53.70% dan 64.76%. Walau bagaimanapun, penghasilan MeOH dan 1-PrOH lebih baik pada suhu yang lebih tinggi. Penghasilan 1-PrOH (170 °C dan 5 jam) mencatatkan penukaran gliserol pada 81.64% dan selektiviti pada 70.85%. Sementara itu, keadaan terbaik dalam pembentukan metanol adalah pada 190 °C, dan masa reaksi 7 jam dengan penukaran gliserol pada 65.87% dan selektiviti produk masing-masing 46.44%

Monitoring Land Cover Changes In The Tropics Using Satellite Remote Sensing Data

Changes in land cover are inevitable phenomena that occur in all parts of the world. Land cover changes can occur due to natural phenomena that include runoff, soil erosion and sedimentation besides man-made phenomena that include deforestation, urbanization and conversion of land covers to suit human needs. Several works on change detection have been carried out elsewhere, however there were lack of effort in analyzing the issues that affect the performance of existing change detection techniques. The study presented in this paper aims to detect changes of land covers by using remote sensing satellite data. The study involves detection of land cover changes using remote sensing techniques. This makes use satellite data taken at different times over a particular area of interest. The data has resolution of 30 m and records surface reflectance at approximately 0.4 to 0.7 micrometers wavelengths. The study area is located in Selangor, Malaysia and occupied with tropical land covers including coastal swamp water, sediment plumes, urban, industry, water, bare land, cleared land, oil palm, rubber and coconut. Initially, region of interests (ROI) were drawn on each of the land covers in order to extract the training pixels. Landsat satellite bands 1, 2, 3, 4, 5 and 7 were then used as the input for the three supervised classification methods namely Support Vector Machine (SVM), Maximum Likelihood (ML) and Neural Network (NN). Different sizes of training pixels were used as the input for the classification methods so that the performance can be better understood. The accuracy of the classifications was then assessed by analyzing the classifications with a set of reference pixels using a confusion matrix. The classification methods were then used to identify the conversion of land cover from year 2000 to 2005 within the study area. The outcomes of the land cover change detection were reported in terms quantitative and qualitative analyses. The study shows that SVM gives a more accurate and realistic land cover change detection compared to ML and NN mainly due to not being much influenced by the size of the training pixels. The findings of the study serve as important input for decision makers in managing natural resources and environment in the tropics systematically and efficiently

An application of robust method in multiple linear regression model toward credit card debt

Credit card is a convenient alternative replaced cash or cheque, and it is essential component for electronic and internet commerce. In this study, the researchers attempt to determine the relationship and significance variables between credit card debt and demographic variables such as age, household income, education level, years with current employer, years at current address, debt to income ratio and other debt. The provided data covers 850 customers information. There are three methods that applied to the credit card debt data which are multiple linear regression (MLR) models, MLR models with least quartile difference (LQD) method and MLR models with mean absolute deviation method. After comparing among three methods, it is found that MLR model with LQD method became the best model with the lowest value of mean square error (MSE). According to the final model, it shows that the years with current employer, years at current address, household income in thousands and debt to income ratio are positively associated with the amount of credit debt. Meanwhile variables for age, level of education and other debt are negatively associated with amount of credit debt. This study may serve as a reference for the bank company by using robust methods, so that they could better understand their options and choice that is best aligned with their goals for inference regarding to the credit card debt