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"Pertumbuhan trafik pengguna internet dari waktu kewaktu mengalami perkembangan yang menakjubkan, oleh karena itu penelitian untuk meningkatkan unjuk kerja jaringan terus dilakukan guna memberikan solusi terhadap penanganan lonjakan trafik yang terjadi dan tuntutan akan kualitas pelayanan oleh end user. Pada disertasi ini dilakukan perancangan dan simulasi dari layanan Available Bit Rate (ABR) dan layanan Guaranteed Frame Rate (GFR) di jaringan Asynchronous Transfer Mode (ATM), guna membantu peningkatan parameter unjuk kerja trafik data TCP/IP (sebagai trafik data internet), juga diharapkan mampu mencegah jaringan dari kondisi kongesti yang sering terjadi jika jumlah pengguna bertambah dan beban trafik terus meningkat.Simulasi layanan ABR yang dilakukan di jaringan ATM adalah dengan menggunakan mekanisme penambahan sumber aktif dan penentuan ukuran buffer. Penggunaan ukuran paket yang berbeda yaitu dengan MSS=512 byte dan MSS=1024 byte sebagai input utama, disamping parameter lainnya. Sedangkan sebagai output-nya adalah total throughput, efisiensi dan fairness ruder.Dari hasil-hasil simulasi melalui layanan ABR dapat ditunjukkan bahwa total throughput dapat mencapai harga maksimumnya selama kapasitas buffer memenuhi dan diperoleh nilai ukuran buffer yang optimal. Disamping itu diperoleh nilai fairness indeks yang tinggi untuk setiap sumbernya. Dengan demikian dapat dipahami bahwa integrasi antara TCP dan layanan ABR di Jaringan Asynchronous Transfer Mode (ATM) dalam teknologi komunikasi data merupakan salah satu solusi yang dapat digunakan untuk memperbaiki unjuk kerja trafik data TCP/IP.Simulasi layanan GFR yang dilakukan di jaringan ATM adalah dengan mengimplementasikan logika fury sebagai metode kendali manajemen buffer yang dikenal dengan nama mekanisme Fuzzy Fair Buffer Allocation (FFBA). Sebagai parameter input pada simulasi ini adalah ukuran buffer sisa dan jumlah sel terkirim, sedangkan parameter output-nya adalah tindakan pembuangan paket dan pengaturan kecepatan terhadap paket yang datang berikutnya.Dari hasil simulasi melalui layanan GFR yang berbasiskan logika fuzzy dapat ditunjukkan bahwa mekanisme FFBA mampu menjamin Minimum Cell Rate (MCR) kendatipun beban trafik yang terus meningkat pada ukuran buffer yang relatif terbatas. Disamping itu, total throughput yang dihasilkan dengan metode ini rata-rata diatas 10% lebih besar dibanding dengan menggunakan metode konvensional (non-fuzzy) dengan pendudukan buffer yang tinggi.

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The growth of Internet traffic user From time to time indicates a tremendous development in telecommunication, therefore the research toward improving the network performance, will be continued to give the solution for handling of enormous traffic that happened, and the user's demand of service quality. In this dissertation it is proposed the design and simulation of AUR and GFR services on ATM network, in order to increase the performance of data traffic of TCP/IP and to avoid the network from the congestion condition when the increasing of the user and traffic loads.

The simulation of ABR service applied on ATM network with using increment of source and determine of buffer size mechanism. The main input of simulation with different of packet size are MSS-512 byte and MSS-1024 byte, beside other parameters included. The outputs of simulation are throughput total, efficiency and fairness index.

From the results of simulation on the ABR service, it is found that TCP can achieve high throughput total when it using sufficient buffer size and optimal buffer size will be found. Beside of this we found high fairness index for all sources. From the results showed that, integration between TCP network and ATM-ABR technology in data communication is one of the available solutions to improve the performance of data traffic of TCP/IP on ATM network.

Using the implementation of fuzzy logic as buffer management control, which is called Fuzzy Fair Buffer Allocation (FFBA) mechanism, did the simulation of GFR service applied on ATM network. The input parameters of simulation are rest of buffer size and the amount of sending cells, where the output parameters are dropping action and rate action for the next packets arrival.

From the results of simulation on the GFR service based of fuzzy logic, it can be showed that a mechanism of the FFBA provides a Minimum Cell Rate (MCR) although, the load of traffic increase continuously on limited buffer size. The throughput total of the system can be achieved 10% (in average) above the usage of conventional mechanism with high buffer occupancy."

"ABSTRAKBiasanya dalam jaringan telekomunikasi yang besar, protokol yang digunakanberaneka ragam. Oleh karena itu dibutuhkan suatu mediation device yang memiliki fungsiuntuk memetakan protokol yang heterogen menjadi sebuah framework definisi.Framework ini diberi code name Hanuman framework. Pada framework ini diperkenalkanmetoda minimalisasi invocation delay dengan menggunakan local interface pada JavaVirtual Machine (JVM) container tunggal dan metode bulk read pada pengaksesan atributentity bean secara berulang. Simulasi menunjukkan perbandingan invocalion delay untuklocal interface vs. remote interface adalah 60,44% dan perbandingan waktu transaksi bulkread vs. single read adalah 26,91% untuk pernbacaan 320 atribut.Gangguan yang terjadi dalam jaringan telekomunikasi dapat mengakibatkanrambatan masalah, oleh karena itu sumber penyebab gangguan harus dapat dideteksi dandikoreksi. Penyebab gangguan diberi nama problem dan akibat gangguan tersebut akanmemberikan alarm yang diberi nama symptom. Dalam penelitian ini diperkenalkan pulametoda inverse symptom dengan pendekatan Humming Distance, yaitu symptom daninversinya, secara teoritis akan memiliki kemampuan yang sama untuk menentukanproblem yang sebenamya, sehingga dapat direduksi. Hasil simulasi menunjukkan metodaini dapat mereduksi symptom hingga 56,94%. Posisi gangguan yang terjadi di suatujaringan dapat diketahui dengan menghitung tingkat korelasi antara problem dengansymptom. Dalam disertasi ini digunakan Bayesian Expectation Maximization (BEM), yaitusuatu teknik estimasi likelihood untuk mengatasi informasi yang tidak lengkap, hilang, ataurusak pada saat observasi pembentukan knowledge base. Hasil simulasi dengan sampledata 1000 buah dan missing data sekitar 70% menunjukkan bahwa metoda ini masihmampu untuk membentuk knowledge based, dan mencari root of fault.

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ABSTRACTIn a large telecommunication network, there are various of protocols that available.Hence there is a need for a mediation device that maps protocols with similar function ofpurpose to be as a definition homework. The framework?s code name is ?Hanuman?framework. This framework introduces invocation delay minimization method a localinterface method on Java Virtual Machine (JVM) single container and bulk readingmethod in accessing entitiy bean attribute continuously. The simulation shows that thecomparison of invocation delay gives local interface vs. Remote interface is 60.44% andthe transaction time of bulk read vs. Single read is 26. 91 % for the 320 attributes reading.A fault in a network can propagate to the other side of the network that generatesignyicant symptoms. The source of faults that occur in a communication network shouldbe detected and corrected The cause of these faults is called problem' and those faultswill generate alarms which named ?symptom ?. This research also introduces inversesymptom method with Hamming distance approach. This method states that symptoms andtheir inverses theoretically have the same meaning and therefore they can be reduced. Thesimulation shows that the reduction of symptoms number due to symptom propagation,and the used inverse symptom method will increase up to 56. 94%. Location of faults thatoccure in a network can be determinted by calculating the correlation level betweenproblems that cause the problem and symptoms, which is event detected in fault locatordevice. This dissertation use Bayesian Expectation Maximization (BEM) that is likelihoodestimation method to be used for overcome hidden information, missing data, or brokendata during observation in knowledge base development. Simulation result with 1000sample data and around 70% missing data shows that the method is capable to developknowledge based and to find the root of fault."

"Akurasi adalah nilai yang menyatakan tingkat kebenaran hasil pengukuran sesuai dengan standard. Untuk mengetahui akurasi sebuah linear transducer diperlukan kalibrasi. Namun sering ditemukan, setelah dilakukan kalibrasi, akurasinya sudah keluar dari batas toleransi yang diijinkan, sehingga tidak layak digunakan lagi. Agar dapat digunakan kembali, perlu dilakukan perbaikan, sayangnya perbaikan secara hardware sangat mahal. Disini disampaikan rancangan metode perbaikan akurasi menggunakan software, dengan memanfaatkan data kalibrasi yang diproses dengan genetic algorithm. Keuntungannya adalah, hanya dengan memasukan data kalibrasi ke software untuk diolah menjadi parameter koreksi. Kemudian diprogramkan ke microcontroller sebagai kompensator maka akan segera diperoleh hasil peningkatan akurasinya.Dalam metode peningkatan akurasi ini, linear transducer didekati hanya dengan monomial dengan membagi sepanjang linear transducer menjadi segmen-segmen kecil dengan suatu algoritma khusus, kemudian dibentuk chromosome untuk monomial pada genetic algorithm (GA) dengan parameternya berupa bilangan integer untuk memudahkan pemrograman pada microcontroler. Kemudian melakukan modifikasi internal GA khususnya pada selection dan crossover operator. Dalam penelitian ini selection operator yang digunakan adalah stochastic universal sampling, dan crossover operator adalah multi point, ternyata kombinasi kedua operator tersebut menghasilkan nilai sum of squares error (SSE) terbaik, sekitar 68.6% dari SSE rata rata.Langkah berikutnya menerapkan metode elitisasi dengan memasukan kembali sebagian elite chromosome ke populasi generasi berikutnya. Dari percobaan diperoleh bahwa dengan 10% elite chromosome menghasilkan nilai root mean squared (RMS) lebih baik yaitu sekitar 38.9 % dari RMS rata rata.Untuk meningkatkan kinerja GA dilakukan segmentasi sepanjang linear transducer. Segmentasi adalah membatasi rentang kerja dengan membagi daerah kerja menjadi beberapa segmen kecil menggunakan nilai golden ratio (GR). Hasilnya ternyata, golden ratio segmentation method mempunyai kinerja lebih tinggi bila dibandingkan dengan hierarchical segmentation method. Nilai RMS menjadi sekitar 49.0% dan jumlah segmen sekitar 85.9%.Selanjutnya untuk mengetahui kinerja metode peningkatan akurasi yang merupakan gabungan dari genetic algorithm dan golden ratio (GA-GR) dilakukan simulasi. Tujuannya adalah untuk meyakinkan bahwa algoritma yang dikembangkan telah berjalan sesuai dengan tujuan penelitian. Dalam simulasi, GA-GR digunakan untuk tracking kurva karakteristik linear transducer. Hasilnya, nilai RMS dari metode GA-GR sekitar 50 - 900 kali lebih baik dari pada menggunakan polinomial.Kemudian untuk mengetahui hasil nyata metode GA-GR dalam meningkatkan akurasi, maka dilakukan percobaan pada linear transducer yang dipasang pada mechanical positioning system, lalu dilakukan kalibrasi menggunakan standard laser interferometer system calibrator dan prosedur British Standard BS 4656. Hasilnya diperoleh bahwa metode GA-GR dapat meningkatkan akurasi sampai dengan 45.1%.Accuracy is the value stating the true level of a measurement result according to the standard. To find out the accuracy of linear transducer, calibration is required. However, it is often found that after calibration is done, the accuracy is out of the permitted tolerance limit. Therefore, it is no longer appropriate to be used. In order to make it useable again, repair is needed to be done but hardware repair is definitely very costly. This dissertation designs a method to increase accuracy by using software, by utilizing calibration data processed by genetic algorithm (GA). The advantage is that it simply needs to enter the calibration data in the software to be processed as correction parameter and the procedure is to be programmed in the microcontroller as the compensator. Then it will soon get the result of the accuracy increment as required.

In this method, the linear transducer is tracked by using only monomial form each small segment of the transducer along its length with a special method of segmenting the linear transducer. Then using the GA to find the parameters of the monomial by putting them into the form of chromosome. To ease the programming in the microcontroller, the parameter values only use integer numbers. The next step the GA internal mechanism is modified, especially in the selection and crossover operators. In this research, the selection operator used is stochastic universal sampling, while the crossover operator is multi point because the combination of those two operators produces the best sum of squares error (SSE), around 68.6% from the average SSE.

The following step is to apply the elitism method by re-entering a subset of elite chromosomes to the next generation population. From the experiments, it can be seen that by re entering 10% of elite chromosomes it will produce better root mean squared (RMS) value, which is around 38.9% from the average RMS.

To increase the GA performance, segmentation a long the length of the linear transducer is done. Segmentation means limiting the work span by dividing the working area into several segments using golden ratio (GR). The result shown that, the golden ratio segmentation method has a higher performance if compared to that with the hierarchical segmentation method. The value of RMS becomes around 49.0% and the number of segments is around 85.9%

Furthermore, to find out the performance of the accuracy increase method which is a combination of genetic algorithm and golden ratio (GA-GR), simulation is conducted. The aim is to make is to make sure that the development algorithm runs in accordance with the objective of the research. In the simulation, GA-GR is used for tracking the curve characteristics of linear transducer. The result is the value of RMS from the GA-GR method is around 50 to 900 times better than using polynomial.

Moreover, to find out the real result of the GA-GR method in increasing accuracy, an experiment on linear transducer on the mechanical positioning system is conducted, using the standard laser interferometer system calibrator and the procedure of British Standard BS 4656. The result obtained is that the GA-GR method can increase accuracy up to 45.1%."

"Pada penelitian ini dikembangkan sistem sensor serat optik dengan cladding termodifikasi lapisan polianilin nanostruktur (nanoserat) untuk mendeteksi uap-uap kimia, meliputi uap amonia (NH3), asam klorida (HCl), metanol (CH3OH), dan uap aseton. Sensor serat optik yang dikembangkan didasarkan pada modulasi intensitas cahaya yang terpropagasi di dalam serat optik akibat perubahan sifat optik (indeks bias atau spektrum absorpsi) cladding modifikasi ketika berinteraksi dengan uap-uap kimia yang dideteksi. Polianilin nanostruktur (nanoserat) disintesis dengan metode polimerisasi antarmuka (interfacial) sistim dua fasa larutan organik/air (aqueous) dan dihasilkan polianilin dalam bentuk terprotonasi atau terdoping (emeraldine salt). Morfologi polianilin diuji dengan mikroskop elektron (SEM), diperoleh morfologi polianilin nanostruktur berbentuk nanoserat dengan diameter beberapa puluh nanometer. Sampel polianilin juga diuji kristalografi dengan difraksi sinar-X (XRD) dan uji spektroskopi FTIR yang mengindikasikan polianilin yang terbentuk adalah emeraldine salt. Uji sifat optik dengan spektrofotometer Vis-NIR memperlihatkan karakteristik spektra spesifik lapisan polianilin dan berubah ketika diberi perlakuan uap-uap kimia (amonia, metanol, aseton dan HCl). Polianilin nanostruktur diterapkan sebagai cladding modifikasi pada serat optik plastik sebagai cladding sensitif. Probe sensor serat optik diuji karakteristik responnya terhadap perlakuan beberapa uap kimia (amonia, HCl, metanol, aseton). Respon dinamik sensor serat optik berupa kurva siklus yang terdiri dari bagian respon dan bagian pemulihan (recovery),yaitu perubahan nilai transmisi intensitas cahaya yang melewati sensor serat optik terhadap waktu. Dari kurva respon ditentukan waktu respon dan waktu pemulihan (recovery) serta juga diketahui kemampuan balik (reversibility) dan kemampuan pengulangan (repeatability). Waktu respon sensor untuk semua uap yang diujikan cukup singkat, yaitu untuk uap amonia, uap asetón dan uap HCl dengan waktu sekitar 20 detik, sedangkan untuk uap metanol lebih lama yaitu sekitar 60 detik. Sebaliknya, waktu pemulihan (recovery time) untuk uap amonia sekitar 50 detik lebih lama dari pada untuk uap metanol (30 detik), uap asetón (10 detik) dan uap HCl (30 detik). Dari kurva siklus respon memperlihatkan kemampuan balik (reversibilitas) sensor yang cukup baik, khususnya untuk respon uap amonia, uap saetón dan uap HCl. Masing-masing siklus tidak memperlihatkan perubahan bentuk yang berarti. Responsivitas sensor terhadap uap kimia memperlihatkan nilai yang berbeda untuk masing-masing uap. Responsivitas terbesar diperoleh untuk uap amonia (1,4 %/detik), diikuti uap aseton (1,25%/detik), uap metanol (0,8 %/detik), dan paling kecil adalah untuk uap HCl (0,05%/detik). Sensor serat optik yang dirancang juga dapat merespon variasi tekanan uap-uap kimia yang diuji dengan batas (limit) deteksi masing-masing, hingga tekanan beberapa puluh mmHg, yaitu 45 mmHg untuk uap amonia dan HCl, 10 mmHg untuk uap metanol dan uap aseton. Respon sensor juga memperlihatkan hubungan logaritmik antara intensitas transmisi terhadap tekanan uap-uap kimia yang diuji dengan linearitas yang cukup baik. Sensitivitas sensor untuk masing-masing uap menunjukkan nilai yang berbeda. Sensitivitas paling baik diperlihatkan oleh sensor uap metanol (0,67 %/mmHg), disusul sensor uap aseton (0,33 %/mmHg), uap amonia (0,20 %/mmHg untuk L=2 cm dan 0,22%/mmHg untuk L=3 cm), dan uap HCl (0,15 %/mmHg)."

"ABSTRACT

A series of experimental studies on the emission spectra of laser-induced plasma at reduced ambient gas pressure were carried out for the analyses of organic materials. The plasma was generated by means of a Q-switch Nd-YAG laser having a pulse width of 8 ns, wavelength of 1,064 nm and operated at an energy of 120 mJ. The emission was detected with time-integrated and time resolved spectroscopic techniques. These studies were intended to investigate the possible extension of the previously established technique of laser induced shock-wave plasma spectroscopy (LISPS) for its applications to organic samples of different natures as well as to examine the related excitation mechanism and the effects of different experimental conditions on the plasma generation.

The first experiment was conducted on soft solid organic samples or samples which have low melting point. It is well known that plasma emission from soft organic samples can not be directly produced by Nd-YAG laser irradiation even in low pressure surrounding gas. We have shown in this experiment that this problem can be overcome by placing a hard sub-target behind or underneath the soft samples or putting an obstacle in front of it. The sharp emission lines of light elements such as hydrogen, carbon and chlorine from organic samples were clearly observed from a black polyvinyl chloride plastic sheet when the shock wave plasma was generated in appropriately chosen low-pressure of the ambient air.

In the second experiment, the same technique has been successfully applied for hydrogen and carbon atomic emission analysis in various fossil samples at low gas pressure around 3 Torr. The quality of the spectrum allows a quantitative comparison of the carbon and hydrogen emission intensities with the associated molecular band spectra, yielding a rough estimation of the period of fossilization process. In the third experiment, another successful application of this technique was also achieved for spectrochemical analysis of bead samples, which offers the possibility of its applications for non destructive identifications of genuine beads as well as its potential application to other areas of forgery inspection.

In addition to the variety of applications demonstrated in those experiments, the related study has also verified the distinct role of laser induced shockwave in the generation of excitation process leading to the observed favorable plasma emission. We show in this connection the crucial condition of low pressure ambient gas for producing the sharp emission lines desirable for high resolution and quantitative analysis. It was further demonstrated that the mass difference between the host elements and the impurity elements has a sensitive effect on the pressure dependent characteristics of the emission lines to be analyzed.

On the basis of those results, we have reason to hold out hope for the extension of the technique developed in this study to more credible quantitative spectrochemical analysis of organic samples, including those of biomedical interest and those in the form of thin films."

"ABSTRACT

A series of experimental studies on the emission spectra of laser-induced plasma at reduced ambient gas pressure were carried out for the analyses of organic materials. The plasma was generated by means of a Q-switch Nd-YAG laser having a pulse width of 8 ns, wavelength of 1,064 nm and operated at an energy of 120 mJ. The emission was detected with time-integrated and time resolved spectroscopic techniques. These studies were intended to investigate the possible extension of the previously established technique of laser induced shock-wave plasma spectroscopy (LISPS) for its applications to organic samples of different natures as well as to examine the related excitation mechanism and the effects of different experimental conditions on the plasma generation.

The first experiment was conducted on soft solid organic samples or samples which have low melting point. It is well known that plasma emission from soft organic samples can not be directly produced by Nd-YAG laser irradiation even in low pressure surrounding gas. We have shown in this experiment that this problem can be overcome by placing a hard sub-target behind or underneath the soft samples or putting an obstacle in front of it. The sharp emission lines of light elements such as hydrogen, carbon and chlorine from organic samples were clearly observed from a black polyvinyl chloride plastic sheet when the shock wave plasma was generated in appropriately chosen low-pressure of the ambient air.

In the second experiment, the same technique has been successfully applied for hydrogen and carbon atomic emission analysis in various fossil samples at low gas pressure around 3 Torr. The quality of the spectrum allows a quantitative comparison of the carbon and hydrogen emission intensities with the associated molecular band spectra, yielding a rough estimation of the period of fossilization process. In the third experiment, another successful application of this technique was also achieved for spectrochemical analysis of bead samples, which offers the possibility of its applications for non destructive identifications of genuine beads as well as its potential application to other areas of forgery inspection.

In addition to the variety of applications demonstrated in those experiments, the related study has also verified the distinct role of laser induced shockwave in the generation of excitation process leading to the observed favorable plasma emission. We show in this connection the crucial condition of low pressure ambient gas for producing the sharp emission lines desirable for high resolution and quantitative analysis. It was further demonstrated that the mass difference between the host elements and the impurity elements has a sensitive effect on the pressure dependent characteristics of the emission lines to be analyzed.

On the basis of those results, we have reason to hold out hope for the extension of the technique developed in this study to more credible quantitative spectrochemical analysis of organic samples, including those of biomedical interest and those in the form of thin films."

"EDFA sebagai penguat optik dapat memperkuat sinyal dalam daerah C-band dengan rentang panjang gelombang 1530-1560 nm. Ketidak rataan penguatan biasanya memunculkan masalah untuk mendapatkan karakteristik penguatan yang rata yang disebabkan oleh cross section yang tinggi pada daerah sekitar 1531 nm. Untuk mengatasi masalah ini, sejumlah metode telah diusulkan. Dalam disertasi ini suatu metode secara eksperimen untuk mendapatkan kerataan penguatan EDFA C-band telah dikembangkan. Kerataan penguatan dapat dicapai dengan mengatur variasi daya sinyal masukan dan daya pompa. Hasil penelitian menunjukkan bahwa panjang EDFA 12 m dapat menghasilkan penguatan rata-rata 20,66-25,23 dB, variasi penguatan 0,47-0,88 dB, noise figure (NF) rata-rata 4,31-4,85 dB, dan variasi NF 0,09-0,12 dB untuk daya sinyal masukan -12,7 dBm dan daya pompa 20-50 mW. Spectral hole burning rata-rata untuk 1530,33-1535,04 nm lebih besar dari 1536,61-1560,61 nm pada perubahan daya sinyal dari -22,7 dBm dan -17,7 dBm menjadi -2,7 dBm. Panjang EDFA 11 m dapat menghasilkan gain maksimum untuk daya sinyal -22,7 dBm hingga -2,7 dBm, dan daya pompa 20 mW hingga 60 mW.

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EDFA an optical amplifier can amplify signals in the C-band region with the wavelength range of 1530-1560 nm. Usually the inhomogeneous gain creates further problems to achieve flat gain characteristics due to high cross section around 1531 nm region. To overcome this problem a number of methods have been proposed. In this thesis an experimental methods to get gain flatness in the C-band EDFA have developed. Gain flatness maybe achieved by tuning the signal input powers, pump power variations.

It is shows that EDFA length 12 m can result average gain 20.66-25.23 dB, gain variation 0.47-0.88 dB, average noise figure (NF) 4.31-4.85 dB, and NF variation 0.09-0.12 dB for input signal power -12.7 dBm and pump power 20-50 mW. Average spectral hole burning of 1530.33-1535.04 nm are greater than 1536.61-1560.61 nm for changing signal power from -22.7 dBm and -17.7 dBm to -2.7 dBm. Length of EDFA 11 m can obtain maximum gain for signal power -22.7 dBm to -2.7 dBm, pump power 20 mW to 60 mW."