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Abstrak :
ABSTRAK
Researchers have evolved several empirical studies with numerous statistical operations for processing of vast Climatic data. However, certain short comings exist in the methodologies as the efforts to quantify the high resolution observations is at most times inappropriate, inaccurate, tedious, complex and expensive. One of the most documented anthropogenic impressions on urban climate is the Urban Heat Island Intensity (U.H.I.I.). To facilitate a simpler and yet scientific understanding of this urban phenomenon: the current study introduces an accurate approach in terms of estimation. The present effort highlights the development of a new technique Simultaneous Extent Analysis (S.E.A.) as a precise representation of U.H.I.I., from the population characteristics of a huge parallel variable climatic database. It orients about the forecasting more specifically with the inception of Neural Network, and training upon a three year continuous knowledge database, using Levenberg Marquardt Backward Propagation method, and the Inference engine as Backward Chaining. The climatic data was a part of meteorological studies collected at half hourly intervals to analyze U.H.I.I. at Bangalore (India). The knowledge base upon training was tested and validated with the real time data for forecasting. The coefficient of correlation of 0.93 between the predicted and actual values is extremely good, thereby depicting that the efficiency of the model is good.

Abstrak :
Skripsi ini membahas tingkat seismisitas, kerapuhan batuan, dan tingkat periode ulang gempa bumi Jawa bagian barat dengan batas koordinat 105º1’11”-106º7’12” Bujur Timur dan 5º7’50”-7º1’11’’ Lintang Selatan. Analisis pengamatan menggunakan data kejadian gempa bumi selama periode 1981-2021, kedalaman h≤300 km, dan magnitudo 𝑀≥2. Metode yang digunakan adalah Magnitude Frequency Relation (MFR) dengan hasil nilai MC sebesar 4.8. Serta metode Maximum Likelihood dengan hasil nilai b sebesar 0.5 - 1.3 dan nilai a sebesar 3.5 – 8.0. Sedangkan nilai periode ulang gempa bumi yang didapatkan berbeda-beda tergantung besaran magnitudo pada wilayah penelitian. Pada gempa bumi dengan magnitudo 𝑀 = 5.0 dan 𝑀 = 5.5, secara berturutturut memiliki kisaran periode ulang gempa sekitar 1-4 tahun dan 2-7 tahun. Beda halnya dengan gempa bumi magnitudo 𝑀 = 6.0 dan 𝑀 = 6.5, memiliki kisaran periode ulang gempa sekitar 4-14 tahun dan 6-16 tahun. ......This thesis discusses the level of seismicity, rock fragility, and the rate of return period for West part of the Java’s earthquake with coordinate boundaries of 105º1’11”- 106º7’12” East Longitude and 5º7’50”-7º1’11’’ South Latitude. Observational analysis uses earthquake data for the period 1981-2021, depth h≤300 km, and magnitude 𝑀≥2. The methods are used Magnitude Frequency Relation (MFR) with MC value of 4.8, also the Maximum Likelihood method with the results of a b value of 0.5 - 1.3 and a value of 3.5 – 8.0. While the value of the earthquake return period obtained varies depending on the magnitude of the study area. Earthquakes with a magnitude of 𝑀 = 5.0 and 𝑀 = 5.5, respectively, have an earthquake return period range of about 1-4 years and 2-7 years. Unlike the case with earthquakes of magnitude 𝑀 = 6.0 and 𝑀 = 6.5, they have a return period of around 4-14 years and 6-16 years.

Abstrak :
Teknologi microarray merupakan analisis terhadap tingkat ekspresi puluhan ribu gen secara paralel untuk melihat perbedaan ekspresi gen. Penelitian microarray menghasilkan suatu nilai yang dirangkum dalam sebuah data yang disebut sebagai data ekspresi gen. Data ekspresi gen umumnya memiliki ukuran yang besar dan penggunaannya luas. Akan tetapi, data ekspresi gen sering mengalami masalah missing values. Data ekspresi gen umumnya mengandung persentase missing values sebesar 10% atau bahkan hingga 90% gen memiliki satu hingga lebih missing values. Salah satu solusi untuk mengatasi adanya missing values adalah dengan menggunakan teknik imputasi.  Pada penelitian ini, diajukan metode imputasi missing values Chronological Biclustering dengan basis PCor-MSRE yang berdasarkan pada konsep biclustering. Penentuan anggota bicluster dengan kesamaan sifat co-expressed dan ukuran magnitude dilakukan berdasarkan pada skor Mean Squared Residue (MSR), jarak Euclidean, dan ukuran jarak korelasi Pearson antara masing-masing gen dengan gen yang mengandung missing values. Dilakukan perhitungan skor MSR, jarak Euclidean, dan ukuran jarak korelasi Pearson pada setiap gen, kemudian dipilih k gen yang memberikan skor terkecil untuk masing-masing kriteria. Selanjutnya, dibentuk bicluster yang digunakan untuk mengimputasi nilai observasi yang missing. Metode ini merupakan pengembangan dari metode SBi-MSREimpute yang cocok digunakan pada data ekspresi gen non-time series atau time series. Metode diimplementasikan pada data ekspresi gen lengkapnon-time series GSE142693 mengenai sel tumor 12 pasien Glioblastoma. Pada data GSE142693, dilakukan konstruksi missing values MCAR dengan missing rate sebesar 5%, 10%, 20%, 30%, 40%, 50%, dan 60%. Performa metode diukur dengan skor NRMSE dan korelasi Pearson, kemudian dibandingkan dengan metode SBi-MSREimpute. Berdasarkan pada skor korelasi Pearson, metode Chronological Biclustering dengan basis PCor-MSRE merupakan metode yang cukup baik dibanding SBi-MSREimpute dalam mengimputasi missing values pada data GSE142693 jika missing rate-nya cukup besar (40%, 50% dan 60%) dengan penggunaan nilai yaitu  dan. Untuk nilai k yang lebih kecil dari 25, metode Chronological Biclustering dengan basis PCor-MSRE cukup baik digunakan (dibanding SBi-MSREimpute) jika jumlah observasi yang missing sebanyak 50% dan 60%. Performa metode Chronological Biclustering dengan basis PCor-MSRE semakin baik seiring dengan membesarnya nilai k yang digunakan. Artinya, performa metode Chronological Biclustering dengan basis PCor-MSRE dapat dipengaruhi oleh penentuan nilai k di awal. ......Microarray technology is an analysis of the expression levels of tens of thousands of genes in parallel to see differences in gene expression. Microarray research produces a value that is summarized in a data called gene expression data. Gene expression data are generally large in size and widely used. However, gene expression data often suffer from missing values problems. Gene expression data generally contain a percentage of missing values of 10% or even up to 90% of genes having one or more missing values. One solution to overcome the missing values is to use the imputation technique. In this research, the method of imputing missing values Chronological Biclustering is proposed on the PCor - MSRE basis which is based on the biclustering concept. Determination of bicluster members with similar co-expressed traits and magnitude measures was carried out based on the Mean Squared Residue (MSR) score, the Euclidean distance, and the measure of the Pearson correlation distance between each gene and the gene containing missing values. The MSR score, Euclidean distance, and Pearson correlation distance measures were calculated for each gene, then k genes were selected that gave the smallest score for each criterion. Next, a bicluster is formed which is used to impute the missing observation values. This method is a development of the SBi-MSRE impute method which is suitable for use in non-time series or time series gene expression data. The method was implemented on the complete non-time series gene expression data GSE142693 regarding tumor cells of 12 Glioblastoma patients. In the GSE142693 data, MCAR missing values were constructed with a missing rate of 5%, 10%, 20%, 30%, 40%, 50%, and 60%. The performance of the method was measured by the NRMSE score and Pearson correlation, then compared with the SBi-MSREimpute method. Based on the Pearson correlation score, the Chronological Biclustering method with PCor - MSRE basis is a method that is quite good compared to SBi-MSRE impute in imputing missing values in GSE142693 data if the missing rate is large enough (40%, 50% and 60%) with the use of namely k=25,k=45,k=65,k=105,k=335, and k=375. For k values less than 25, the Chronological Biclustering method on the basis of PCor - MSRE is quite good to use (compared to SBi-MSRE impute) if the number of missing observations are 50% and 60%. The performance of the Chronological Biclustering method on the PCor - MSRE basis is getting better as the value of k used increases. This means that the performance of the Chronological Biclustering method on the PCor-MSRE basis can be affected by determining the initial k value.

Abstrak :
Penelitian ini bertujuan untuk mengetahui hubungan antara magnitude perubahan serta prior rating dari bond rating terhadap nilai abnormal return. Penelitian menggunakan sampel dan observasi perubahan bond rating yang dikeluarkan PT. PEFINDO selama periode 2000-2008. Pengujian dilakukan menggunakan regresi untuk melihat pengaruh hubungan antara magnitude dan prior rating dengan cumulative abnormal return. Selain itu dilakukan pengujian tambahan dengan pembagian observasi menurut peningkatan dan penurunan rating serta pembagian sesuai dengan prior rating. Penelitian ini menemukan adanya hubungan signifikan antara magnitude perubahan bond rating dengan abnormal return namun tidak pada variabel prior rating. Pada pengujian tambahan, ditemukan adanya nilai abnormal return yang signifikan di sekitar event penurunan bond rating, namun tidak pada peningkatan bond rating.

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The main objectives on this research is to examine the effect of bond rating change's magnitude and prior rating to stock?s abnormal return. This research used bond rating changes issued by PT. PEFINDO as its samples and observations. The research used regression method to measures the relationship between bond rating change's magnitude, prior rating and stock's abnormal return. Additional test also used in this research by dividing observations by upgrades and downgrades, and by their prior ratings. The research found out that abnormal return are associated to bond ratings change's magnitude, yet there are no relationship between prior rating and abnormal return. The additional test results imply that there are significant abnormal returns around rating downgrades but not in upgrades.

Abstrak :
This paper is aimed towards analyzing and modeling earthquake interoccurence times in the Lesser Sunda Islands region using Weibull distribution. The data were classified into three categories, based on their magnitude; i.e. weak, medium, and strong earthquakes. Cumulative distribution functions and hazard rates are also explored in order to obtain the characteristics of earthquake inter-occurrences time data. Empirical results indicate the probability and rate of an earthquake recurrence time with a certain magnitude and in a certain time. Medium and weaker earthquakes have a higher chance of occurrence, reaching up to a 100% probability for the following 60 months. Meanwhile, the stronger earthquake has a 75.80% probability of occurrence. It can be seen that the earthquake occurrence probability increases together with the time increment factor.

Abstrak :
This study discusses the evaluation of Hara’s model to estimate seismic moment magnitude (MW) by using teleseismic waveform data, and then presents the development of an extended Hara model. Both models use the maximum amplitude of displacement and epicenter distance, as well as the duration of high-frequency energy radiation, of the vertical component of earthquake P-wave records. Nineteen moderate-magnitude (5.0 £ MW£ 7.0), shallow (depths £ 70 km), Sumatra subduction megathrust earthquake data sets recorded by the KAPI seismograph station (Kappang, South Sulawesi) in 2010 and 2011 were used in this study. The analysis is performed to obtain the maximum amplitude of displacement, epicenter distance, and the duration of high-frequency energy radiation on the first arriving P-wave. The main results show that Hara’s model (2007) overestimates MW to be less than 7.0 compared with that obtained from the Global Centroid Moment Tensor (CMT) catalog. The extended Hara model was developed with the use of the same basic equation, and the resulting coefficients are ? = 0.538792, ? = 0.783840, ? = 0.242616, and ? = 4.929095. The mean and standard deviation of the difference between the extended Hara model and the Global CMT catalog are 0.01 and 0.14, respectively.

Abstrak :
Vortex tube adalah separator energi yang menggunakan aliran tangensial (vortex). Dengan inlet berupa jet tangensial, terjadi medan aliran vortex yang menyebabkan perbedaan temperatur diantara duo outlet. 5atu outlet di bagian peripheral mempunyai temperatur lebih tinggi, yang outlet di bagian tengah mempunyai temperatur lebih rendah dibanding inlet. Tujuan dari penelitian ini adalah untuk mernpelajari medan aliran di dalam vortex tube dengan CFI), dengan menggunakan model turbulen RNG. Analisa medan aliran ini mencakup: flow pattern: distribusi kecepatan oksial, kecepatan total, distribusi tekanan static dan tekanan total, distribusi temperatur total. Hasii ini akan divalidasi dengan hasil pengukuran temperatur total melalui eksperimen. Proses komputasi menggunakan model komputer dengan dimensi soma dengan eksperimen, model turbulensi RNG, dengan input kecepatan yang dihitung berdasarkan pengukuran laju aliran rnassa inlet dan outlet dalam eksperimen. Keunikan model eksperimen ini terletak pada swirling generator yang mempermudah input tangensial udara kompresor, walaupun disederhanakan dalam model komputer. Selain itu, komputasi ini berhasil memadelkan katup jarum, sehingga komputasi ini memberikan hasil yang lebih akurat di daerah katup Sarum. Hasil komputasi menunjukkan adanya daerah aliran-bolik (reversal flow) di dalam vortex tube. Aliran batik ini terjadi terutama pada daerah sumbu sampai jarak radial 0.5 RID, dan jarak aksial dari inlet sampai 7.8 XID. Hasil penting lainnya adalah bentukon duo bush vorteks, vorteks luar yang membentuk distribusi kecepatan seperti vorteks Rankine, don vorteks dalam yang membentuk distribusi kecepatan seperti vorteks bebas, dengan kecepatan di sumbu yang lebih tinggi dibandingkan kecepatan pada radius yang lebih besar. Batas ke duo vorteks tersebut terletak di antar 0.4 sampai dengan 0.5 RID. Hasil komputasi juga memperlihatkon pengaruh dominan dari medan aliran terhadap temperatur total. Data eksperimen memvalidasi trend temperatur total raja, tanpa kesesuaian nilai temperatur total.

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Vortex tube is energy separator using tangential inlet. The vortex flow-field created temperature differences at the two outlets. One outlet at the tube's periphery had higher temperature, and the other outlet at the center with lower temperature. The temperature differences at both outlets might be reached 80K at 6 bar pressure inlet.Computational model was built up in such way, with the same dimensions, velocity inlet and pressure outlet that counted down from the parameters that have been used in the experiment as the boundary conditions. RNG turbulence-model was used to solve the governing equations. The unique swirling generator was used in the experiment to simplify the distribution for air tangential-inlet, although it is simplified in the computer model. Besides, the needle valve has been able to be modeled. It brings more accurate of the flow field's result at the valve's area. The results: the figures of the flow patterns: axial velocity, velocity magnitude, static and total pressure, and the distribution of total temperature. The result of total temperature distribution is validated with the experiment's result.The computational result shows a reversal flow in the certain area in the vortex tube. The reversal flow occurs in the axis until radial distance 0.5 Rib, with axial distance from inlet area until 7.8 XIS. Be-side, there is curve of two integrated vortex. The outer vortex formed like Rankine vortex, and the inner vortex with free-vortex distribution, which has higher velocity in the core than the peripheral. The flow field dominates the total temperature distribution, thus they are formed likely, with radii of both inner and outer vortex between 0.4 and 0.5 RID, as the velocity magnitude distribution curve. The experimental data figures the same trend as the computational result, but with non-suited value.

Abstrak :
Penelitian ini dilakukan untuk memilih diantara dua koridor penghubung kota Jakarta dengan Bekasi yang akan terlebih dahulu diterapkan sistem pengumpan transjakarta. Dua koridor penghubung tersebut adalah Jalan Bekasi Raya dan Jalan Raya Kalimalang. Parameter pemilihan dalam dalam penelitian ini adalah besaran permintaan penumpang, biaya operasional armada, dan potensi pemasukan. Maetode yang dipakai adalah berbasiskan koridor, dengan membuat rencana operasional pelayanan pada kedua koridor. Dalam penelitian ini dilakukan 3 skenario yang akan diterapkan, yaitu tanpa perubahan geometrik, dilakukan perubahan geometrik dengan biaya ditanggung pemerintah, dan dilakukan perubahan geometrik dengan biaya ditanggung operator. Hasil yang didapatkan adalah pada skenario 1 dan 3 koridor yang dipilih untuk dioperasikan terlebih dahulu adalah Jalan Bekasi Raya, sedangkan pada skenario 2 tergantung dari harga tarif yang ditetapkan. ......This study is conducted to choose which of the two alternatives of corridor between Jakarta and Bekasi to be implemented first as Transjakarta feeder system. The alternatives are through Bekasi Raya Street and through Kalimalang Street. The parameters used in this study are total potential demand, operational cost, and potential revenue of each corridor. There are three scenario constructed, without geometric changes, with geometric changes by govermental fund, and with geometric changes by operator?s fund. The result suggest that in the 1st and 3rd scenario it?s better to implement Bekasi Raya Street corridor, while in the 2nd scenario the choice depends on the price of the service.