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"A study was performed on a laser-induced shock wave plasma generated on high concentration Au-Ag-Cu alloys by a Q-switched Nd-YAG laser of 4.8 mJ under reduced air pressure of 2 Torr. It was found that the total emission intensity of the secondary plasma is proportional to the intensity of the primary plasma, Assuming linear proportionality between the intensity of the primary plasma and the number of atoms vaporized from the target, it is proposed that the quantitative analysis can be applied to the intensities of the analytical emission Iines normalized by the total intensity of the primary plasma. This experimental result demonstrated for each metal element shows an excellent linear relationship between the normalized emission line intensity and the content of corresponding element after primary plasma normalization."

"Indikator untuk mengukur tingkat kesejahteraan rumahtangga bersifat relatif. Dalam tugas akhir ini telah ditemukan bahwa tingkat kemampuan sosial ekonomi rumahtangga di DKI Jakarta yang heterogen dapat dibagi ke dalam beberapa kelompok/cluster yang relatif homogen. Metode yang digunakan adalah Analisis Cluster. Dengan Analisis Cluster pengelompokan terhadap obyek/individu akan menghasilkan variabilitas yang rendah untuk obyek-obyek yang berkumpul dalam satu cluster, dan variabilitas yang tinggi untuk obyekobyek dari cluster yang berbeda. Data yang digunakan adalah data SUSENAS tahun 1993 untuk propinsi DKI Jakarta dengan besar sampel 3058 rumahtangga. Dengan metode Partisi K-Mean, 3058 rumahtangga yang diukuroleh 21 variabel dapat dikelompokw ke dalam 7 cluster, dan komposisi ke-tujuh cluster tersebut kemudian dirangkum dalam 3 kelompok sosial ekonomi."

"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."

"Practical Byzantine Fault Tolerance (PBFT) adalah algoritma konsensus yang digunakan dalam consortium blockchain. Jenis blockchain ini menyediakan platform yang menghubungkan sekelompok peserta yang saling terkait ini. Hal ini sesuai  untuk implementasi pertukaran informasi Building Information Modeling (BIM) yang merupakan representasi digital dari karakteristik fisik dan fungsional dari suatu bangunan. Pertukaran informasi ini melibatkan banyak pihak seperti pemilik bangunan, kontraktor, sarjana konstruksi, sarjana listrik, manager lokasi dan banyak dokumen BIM. Pihak-pihak ini dapat mempunyai konflik satu sama lain dan dapat menyebabkan bahaya, untuk itu lebih baik menggunakan algoritma PBFT. Algoritma ini dapat memberikan toleransi sampai dengan 1/3 node yang berbahaya/rusak. Namun, algoritma ini mempunyai karakteristik yaitu membutuhkan komunikasi intensif antar node, yang membatasi skalabilitas dan kinerjanya. Solusi yang diusulkan untuk mengatasi hal ini adalah dengan menggunakan algoritma konsensus baru Byzantine Fault Tolerance dengan struktur hirarki network double-layer (Double-layer Byzantine Fault Tolerance). Stuktur hirarki network dapat mengurangi penggunaan bandwidth dan tekanan komunikasi antar peer. Pada struktur ini terdapat dua lapisan node. Node di lapisan pertama mengirimkan pesan pada beberapa node di lapisan kedua. Setiap node pada lapisan pertama terhubung dan membentuk kelompok dengan beberapa node pada lapisan kedua dan saling berkomunikasi. Setiap kelompok ini menjalankan algoritma Byzantine Fault Tolerance untuk mencapai subkonsensus. Konsensus akhir didapatkan dengan menggabungkan subkonsensus pada lapisan pertama dan semua subkonsensus di tiap kelompok. Hasil penelitian menunjukkan algoritma ini dapat meningkatkan skalabilitas dengan mengurangi jumlah pertukaran pesan antar node sebesar 84% dan waktu untuk mencapai konsensus sebesar 70% dibanding dengan struktur network peer-to-peer.

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Practical Byzantine Fault Tolerance (PBFT) is a consensus algorithm used in a consortium blockchain. This type of blockchain provides a platform that connects a group of interrelated participants. This is suitable for the implementation of Building Information Modeling (BIM) information exchange, which is a digital representation of the physical and functional characteristics of a building. The information exchange involves many parties such as building owners, contractors, construction engineers, electrical engineers and site managers and BIM-related documents. These parties may have conflicts with each other and can cause harm. Thus, it would be better to use the PBFT algorithm. This algorithm tolerates up to 1/3 malicious/faulty nodes. However, this algorithm has inherent characteristic that it requires intensive communication between nodes, which limits its scalability and performance.

The proposed solution is to use a new consensus algorithm Byzantine Fault Tolerance with a double-layer network hierarchy structure called Double-Layer Byzantine Fault Tolerance (DLBFT). The hierarchical structure of the network can reduce bandwidth usage and peer communication stress. This structure consists of two layers of nodes. Nodes in the first layer send messages to several nodes in the second layer. Each node in the first layer is connected and forms a group with several nodes in the second layer and communicates with each other. Each group runs the Byzantine Fault Tolerance algorithm to reach a subconsensus. The final consensus is obtained by combining the subconsensus in the first layer and all subconsensus in each group. The results show that this algorithm can improve scalability by reducing the number of messages exchanged between nodes by 84% and the time to reach consensus by 70% compared to peer-to-peer network."

"Kota Tasikmalaya, Jawa Barat, memiliki potensi pertumbuhan pembangunan tinggi sebagai Pusat Kegiatan Wilayah Priangan Timur dan Pangandaran. Diperlukan upaya strategis untuk mengurangi dampak kerugian dan korban jiwa jika terjadi gempabumi karena kota ini masuk dalam kategori indeks risiko tinggi bencana gempabumi. Penelitian bertujuan mengkaji pola spasial bahaya dan risiko gempabumi untuk menghasilkan peta yang menjadi dasar dalam mengevaluasi kesesuaian kawasan permukiman. Kajian dilakukan dengan metode analisis kuantitatif dan analisis spasial berdasarkan indikator fisik, sosial, dan ekonomi. Pola spasial bahaya tinggi gempabumi dibentuk lapisan batuan dengan indeks kerentanan seismik dan PGA permukaan tinggi serta kestabilan struktur tanah rendah yang membujur di bagian timur Kecamatan Purbaratu menerus ke bagian timur Kecamatan Cibereum hingga bagian utara Kecamatan Tamansari dan sebagian kecil Kecamatan Kawalu. Wilayah tersebut berpotensi mengalami guncangan lebih kuat dibanding daerah sekitarnya yang divalidasi dengan data kerusakan gempabumi 2 September 2009. Pola spasial risiko bencana gempabumi tinggi terjadi akibat tingkat bahaya dan kerentanan tinggi serta rendahnya kapasitas wilayah yang membentuk pola spasial mengelompok di wilayah timur, tepatnya di Kecamatan Cibeureum, Kecamatan Tamansari, dan sebagian kecil Kecamatan Purbaratu. Sementara risiko kerugian tinggi membentuk pola spasial mengelompok di pusat perkotaan yang memiliki sarana prasarana lebih lengkap. Evaluasi kesesuaian kawasan permukiman berbasis bencana gempabumi menunjukkan kawasan permukiman di Kota Tasikmalaya sebagian besar berada pada daerah risiko rendah. Hal ini menunjukkan pemerintah Kota Tasikmalaya sudah cukup baik dalam perencanaan dan implementasi perijinan pembangunan kawasan permukiman.

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Tasikmalaya Municipality, West Java, has high development growth potential. Strategic efforts are needed to reduce the impact of losses and casualties from an earthquake because it has a high-risk earthquake index. This study aims to examine the spatial pattern of earthquake hazards and risks as the basis for evaluating settlement suitability that is safer from earthquakes. This research was conducted using quantitative and spatial analysis based on physical, social, and economic indicators. The spatial pattern of earthquake hazard is formed by the higher seismic vulnerability index and surface PGA and low soil structure stability that stretches from the eastern of Purbaratu continuously to the eastern Cibereum to the northern Tamansari and a small part of Kawalu. Earthquake shocks in the area will be stronger than the surrounding area, as validated by the damage data from the 2 September 2009 earthquake. The high risk of earthquakes, due to the high level of hazard and vulnerability as well as the low regional capacity, forms a clustered spatial pattern in the eastern region, precisely in Cibeureum, Tamansari, and a small part of Purbaratu. Meanwhile, the high risk of loss forms a clustered spatial pattern in the downtown, which has more complete infrastructure facilities. Evaluation of settlement suitability based on earthquake risk shows that most of the settlement areas are in low-risk areas. This evaluation shows that the government of Tasikmalaya Municipality is quite good at planning and implementing permits to develop settlement areas.

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