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Abstrak :
One of the main reasons for continuing interest in shock focusing is its ability to concentrate energy in a small volume and produce extreme temperatures and pressures in fluids in a controlled laboratory environment. The phenomenon of shock wave focusing leading to extreme conditions in fluids during micro- and nanosecond time intervals is a spectacular example of mechanics at small length and time scales revealing the major properties of shock dynamics including high-temperature gas phenomena. Production of high-energy concentrations in gases and fluids with star-like temperatures and extreme pressures by means of a stable imploding shock is of great interest not only in its own right but also because of the connection to a multitude of phenomena in nature, technology and medicine.

Abstrak :
ABSTRACT
A comprehensive study has been made on the dynamical process taking place in the laser-plasma generation i.nduced by a TEA CO2 laser bombardment on metal target and non-metal target Eom low to high pressures surrounding gas. ln the case of metal target, pure zinc plate was used as a target and bombarded with 400 ml laser pulse energy. Dynamical characterization of plasma expansion and excitation were examined in detail both for target atomic emission (Zn I 481.0 nm) and gas atomic emission (He I 587.6 nm) by using an unique time-resolved spatial distribution measurement and conventionalemission spectroscopic detection method. The results showed that the plasma expands and develops with time. The mechanism of plasma generation can be classified into three cases depending on the surrounding gas pressures; target shock wave plasma in the pnessure range between 2 Torr and 20 Torr, coupling shock wave plasma in the pressure range between S0 Torr and 200 Torr and gas ?break down shock wave plasma in the pressure range between 200 Torr and 1 atm. In all cases in the laser-plasma generation under TEA CO; laser bombardment on metal target, shock wave process-always plays important role for exciting the target atoms and gas molecules.

ln the case of , non-metal target, a museum glass was used as a target and bombarded with a 400 mJ laser; pulse energy By using the conventional emission spectroscopic detection method, namely temporally and spatially integrated and time-resolved spatially integrated of plasma emission, it was shown that the plasma mainly consists of target atomic emission. Only weak gas atomic emission intensity could be observed even at 1 atm of surrounding gas pressure. These results indicate that the gas breakdown is not a major process responsible to the plasma formation even at high pressure surrounding gas. Shock wave process was considered as an important role in this plasma formation. By the use of shadowgraph technique to detect the density jump signal due to the shock wave front involving a He-Ne laser as a probe light, simultaneous detection of the shock wave Bent and the emission iiont was successfully implemented. The result showed that at the initial stages of plasma expansion shock wave 'dont and emission front coincide and move together with time. At the later stages of plasma expansion the two fronts become separate with the emission front left behind the shock wave front. These results are completely coinciding with the shock wave plasma model. Unfortunately, in this experiment we succeed to detect the density jump signal only for high pressure surrounding gas, above 100 Torr. At the pressures lower than 100 Torr the density jump signal was very weak and it is diflicult to distinguish with the noise including in the signal.

The other important experimental results that support the shock wave plasma model were also obtained in this experiment, namely the coincidence of emission iziont regardless of their atomic weight and sub-target effect. By using lead glass as a sample, which contain Pb, Si, and Ca, it was confirmed that the emission front of the Pb 1450.8 nm, Si I 288.2 nm and Ca I 422.6 nm almost coincide regardless of their atomic weight. This result also supports the shock wave plasma model because, by the stagnation of the propelling atoms, the front position of the all atoms coincides regardless of its mass. In the case of sub-target effect, we confirmed that plasma could be produced even for sch target if sub-target is set behind the sample. In this case we use a sample as a sub-target and a vinyl tape was attached to the quartz sample as a target. The TEA CO2 laser bombardment was used at 150 mJ and at 1 atm of air. The main role ofthe subtarget is to produce a repulsion force for atom gushing with high speed. For shock wave, high speed is necessary condition to compress the gas.

Coincidence of the movement of the shock wave iiiont and the emission front in the initial stages of plasma expansion is a direct proof of the shock wave plasma model. By improving the detection technique of the density jump associated with the shock wave, the correlation between the shockwave fiont and the emission front was examined in detail. For this purpose rainbow interferometer system, which has higher sensitivity compared with the shadowgraph technique, was used to detect the density jump signal. We succeed to realize simultaneous detection of shock wave front and emission front iiom 3 Torr until 1 atm of air when a quartz sample is bombarded with a 600 mJ TEA CO2 laser. In all pressure that were examined, the shock wave front and the emission front always coincide and move together with time in the initial stages and separate at the later stages with emission front left behind the shock wave tiont. The coincidence of the shock wave iiont and emission front and move together with time at the initial stages of plasma expansion was also obtained by using ruby as a sample at 10 Torr and 100 Torr of air as well as with museum glass at the same laser pulse energy.

Abstrak :
Extracorporeal Shock Wave Lithotripsy (ESWL) merupakan terapi non-invasif yang menjadi tatalaksana lini pertama batu ureter. Terdapat berbagai faktor yang diduga dapat mempengaruhi tingkat keberhasilan ESWL, diantaranya lokasi batu dan ukuran batu ureter. Penelitian ini bertujuan untuk membuktikan adanya hubungan antara lokasi batu dan ukuran batu dengan tingkat keberhasilan ESWL pada pasien batu ureter. Penelitian dilakukan di Departemen Urologi Rumah Sakit Cipto Mangunkusumo dengan mengambil 106 data rekam medis pasien laki-laki tahun 2009-2011 dengan batu ureter unilateral yang sudah dilakukan ESWL. Data kemudian dikelompokkan sesuai dengan kategori ukuran batu (diameter <10 mm atau ≥10 mm) dan lokasi batu (proksimal atau distal ureter), lalu dihitung persentase keberhasilan ESWL dan dianalisis dengan uji regresi logistik untuk melihat kemaknaannya. Didapatkan bahwa sampel memiliki rentang usia 27-74 tahun (mean 43,5 tahun). Persentase keberhasilan ESWL lebih tinggi pada batu ukuran <10 mm (92,4%) dibanding batu ukuran ≥10 mm (70,4%) (p=0,01, OR: 4,806(1,453-15,905)). Didapatkan juga persentase keberhasilan ESWL lebih tinggi pada batu ureter proksimal (92,2%) dibandingkan ureter distal (78,6%) (p=0,081, OR: 2,957(0,875-9,987)). Disimpulkan bahwa terdapat hubungan bermakna antara ukuran batu ureter dengan tingkat keberhasilan ESWL tetapi tidak terdapat hubungan lokasi batu ureter dan tingkat keberhasilan ESWL. ......Extracorporeal Shock Wave Lithotripsy (ESWL) is a non-invasive, first-line treatment for ureteral stone. There are multiple factors thought to be influencing its success rate, including stone location and size in the ureter. This study's objective was to prove the relationship between stone location and size with ESWL success rate in male unilateral ureteral stone patients. This study was done at Urology Departement Cipto Mangunkusumo Hospital. 106 patients met the inclusion criteria. The collected data were then grouped according to their categorizations for stone size (<10 mm or ≥10 mm) or location (proximal or distal), then their ESWL successs percentage were counted and analyzed using regression logistic test. It was found that from samples with age ranging from 27-74 years old (mean 43,5 years old), the ESWL success rate in <10 mm stone size patients was higher (92,4%) than in ≥10 mm size (70,4%) (p=0,01, OR: 4,806(1,453-15,905)). It was also found that ESWL success rate in proximal stones is higher (92,2%) than in distal stones (78,6%) (p=0,081, OR: 2,957(0,875-9,987)). In conclusion, there was a relationship only between ureteral stone size with ESWL success rate in ureteral stone patients, but there was no relationship ureteral stone location and ESWL success rate.

Abstrak :
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.

Abstrak :
Penelitian ini menguji metode Deterministic Queuing dan metode Shock Wave untuk menganalisa kemacetan lalu lintas rutin akibat bottleneck pada ruas jalan dengan hambatan (non freeway) berdasarkan prinsip dinamika lalu lintas. Dinamika lalu lintas menggambarkan bahwa arus lalu lintas berubah secara konstan berdasarkan ruang dan waktu sebagai hasil interaksi antara pengemudi, kendaraan, dan jalan. Prinsip konservasi kendaraan akan digunakan dalam menganalisa mekanisme dinamik arus lalu lintas pada kondisi macet. Penelitian ini bertujuan untuk mendapatkan rekomendasi mengenai penggunaan metode yang tepat dalam menganalisa kemacetan lalu lintas rutin akibat bottleneck pada jalan dengan hambatan, shock wave method ataukah deterministic queuing method. Selain itu juga untuk mengetahui apakah hasil analisa dengan Shock Wave Method over estimate dibandingkan dengan hasil analisa dengan Deterministic Queuing Method, seperti halnya pada penelitian yang pernah dilakukan sebelumnya pada freeway. Lokasi bottleneck yang diambil adalah di Jalan Rasuna Said, Jakarta Selatan dan di Jalan Laksamana Yos Sudarso, Jakarta Utara. Survey lapangan dilakukan pada lokasi sebelum memasuki ruas bottleneck dan pada ruas bottleneck itu sendiri. Data primer hasil survey adalah waktu tempuh kendaraan dan volume lalu lintas. Kemudian data tersebut diolah untuk mendapatkan data hasil olahan untuk digunakan dalam analisa kemacetan dengan kedua metode tersebut. Perbandingan hasil penggunaan kedua metode tersebut dapat dilihat secara grafis maupun analitis. Secara grafis dihasilkan time-space diagram, Queuing Diagram, dan physical discharging rate diagram. Dimana masing-masing merupakan hasil superimposisi dari beberapa grafik. Sedangkan perbandingan secara analitis didapatkan dari membandingkan beberapa hasil estimasi dengan menngunakan kedua metode tersebut.

Abstrak :
A special interferometric technique with high sensitivity has been devised on the basis of rainbows refractometer without the use of an additional and delicate amplitude-splitting setup. This new technique was use for the characterization of shock wave plasma induced by a Q-sw Nd-YAG laser on various kinds of metal samples under reduced gas pressures. An unmistakable signal of density jump was detected simultaneously with the emission front signal. It is proved that at the initial stage of the secondary plasma expansion, the front of the emission and the front of the blast wave was coincide and move together with time. However, at a later stage, the front of the emission will separate from that of the blast wave induced in the surrounding gas at low pressures. Using Cu and Zn samples, the experimental result showed that the separation of the emission front and blast wave front took place at 4 mm above sample surface for the laser energy of 140 mJ.

Abstrak :
In spite of abundant experimental evidences supporting the viability of the laser induced shock wave plasma model for the explanation of the important features ofthe plasma and the associated spectroscopic characteristics, a controversy on the atomic excitation mechanism in the plasma has remained to be completely resolved. In this study the contributions of the shock wave model and two other most popular models, the electron-ion recombination model and thc electron collision model were thoroughly investigated. For that purpose, a special technique has been developed for the direct detection of the charge current in conjunction with plasma emission measurement dining the laser plasma generation and expansion. The current detection was performed by placing a partially transmitting metal mesh electrode at a distance in front of the sample surface with the sample target sewing as the counter electrode. The electric Held between the mesh and sample surface was set up and varied by applying a variable DC voltage (0-400 Volt) between them. The laser plasma was generated by a YAG laser (64 ml, 8 ns) tightly focused on a Cu target through the mesh electrode in low-pressure surrounding gas. It was found that the charge current time profiles obtained at various gas pressures invariably exhibit a lack of consistent correlation with the emission time profile of the plasma throughout most of the emission period. The result of this study has thus practically eliminated any significant roles ofthe electron-ion recombination and electron collision models in the excitation process. We are therefore led to conclude that the shock wave model proposed earlier is most plausible for the consistent explanation of the secondary plasma emission, while the other two models may have some contribution only at the very initial stage ofthe secondary plasma generation.

Abstrak :
ABSTRACT
In spite of abundant experimental evidences supporting the viability of the laser induced shock wave plasma model for the explanation of the important features ofthe plasma and the associated spectroscopic characteristics, a controversy on the atomic excitation mechanism in the plasma has remained to be completely resolved. In this study the contributions of the shock wave model and two other most popular models, the electron-ion recombination model and thc electron collision model were thoroughly investigated. For that purpose, a special technique has been developed for the direct detection of the charge current in conjunction with plasma emission measurement dining the laser plasma generation and expansion. The current detection was performed by placing a partially transmitting metal mesh electrode at a distance in front of the sample surface with the sample target sewing as the counter electrode. The electric Held between the mesh and sample surface was set up and varied by applying a variable DC voltage (0-400 Volt) between them. The laser plasma was generated by a YAG laser (64 ml, 8 ns) tightly focused on a Cu target through the mesh electrode in low-pressure surrounding gas. It was found that the charge current time profiles obtained at various gas pressures invariably exhibit a lack of consistent correlation with the emission time profile of the plasma throughout most of the emission period. The result of this study has thus practically eliminated any significant roles ofthe electron-ion recombination and electron collision models in the excitation process. We are therefore led to conclude that the shock wave model proposed earlier is most plausible for the consistent explanation of the secondary plasma emission, while the other two models may have some contribution only at the very initial stage ofthe secondary plasma generation. Key words: charge current, shock wave, electron-ion recombination and electron collision. Praiseci is to the Lord for He is my reason in everything I do. This manuscript is never be done without the guidance by Pro£ Tjia May On, to whom I am extremely grateful. He also provided the support without which this thesis would not possible. He is more than just a teacher for me for his words have deeply touched me. Moreover, he also introduced me that knowledge is something we should share among others and to improve the education in my country. I am also indebted to Prof. Kiichiro Kagawa at the Fukui University for providing the atmosphere and the physical resources to make thesis writing in these times of fast paced research. I am also thankful for the opportunity which is given to me to join research together with him in his laboratory in Japan. Extra special thanks go to Dr. Hendrik Kurniawan for providing me with encouragement and support for this project. He is the first one who encouraged me to take Doctor Cotuse Program which seemed impossible at the beginning. His companion during research at Applied Spectroscopy Laboratory at University of Indonesia is a leading experience in research for me. I am particularly grateful to the excellent team of referees who provided critical comments on this thesis. Their feedback was a great benefit to me. I gratefully acknowledge all my colleagues: Rinda Hedwig, Mangasi A. Marpaung, Hery Suyanto, MM. Suliyanti, Wahyu S. Budi, and Emon in Applied Spectroscopy Laboratory at University of Indonesia, for their assistance and support during my study. My never-ending thanks to my beloved family, especially to my parents who exhibited thoughtful patience over extended periods of time when I seemed to be invisible. Thanks also to Loviana who helped me in all situations which I no longer can resist by myselfl Finally, I apologize to all those who helped that I did not acknowledge specifically. I know there were many and greatly appreciate your assistance. August, 2002 Author

Abstrak :
Baground: the optimal management of lower calyceal stones is still controversial, because no single method is suitable for the removal of all lower calyceal stones. Minimally invasive procedures such as extracorporeal shock wave lithotrispy (ESWL), percutaneous nephrolithotomy (PNCL) and flexible ureteroscopy (fURS) are the therapautic methods for lower calyceal stones. the aim of this study was to identify the optimal management of 10-20 mm lower pole stones. Methods : a meta-analysis of cohort studies published before July 2016 was performed from Medline and Cochrane databases. Management of 10-20 mm lower pole stone treated by fURS, ESWL and PCNL with follow-up of residual stones in 1-3 months after procedure were include and urinary stone in other location and size were exclude. A fixed-effects model with Mantzel-Haenzel method was used to calculate the I2 statistic. All analyses were performed with review manager 5.3. Result : we analized 8 cohort studies. The stone free rate from 958 patient (271 PCNL, 174 fURS and 513 ESWL), 3 months after operation, was 90.8% (246/271) after PCNL; 75.3% (131/174) after fURS; and 64.7% (332/513)after ESWL. Base on stone free rate in 10-20 mm lower pole stone following management, PCNL is better than fURS (overall RR was 1.32 (95% CI 1.13-1.55) ; p<0.001 and I2=57%) and ESWL (overall risk ratio 1.42 (95% CI.30-1.55); p=<0.001 and I2=85%). But if we compare between fURS and ESWL, fURS is better than ESWL base on stone free rate in 10-20 mm lower pole stone management with overall RR 1.16 (95% CI 1.04-1.30; p=0.01 and I2=40%). Conclusion: percutaneous nephrolithotomy provided a higher stone free rate than fURS and ESWL. This meta-analysis may help urologist in makin decision of intervention in 10-20mm lower pole stone management.

Abstrak :
This book presents a wealth of images of shock wave phenomena, gathered by the author over the past 40 years. Shadowgrams and interferograms of basic shock-dynamic topics such as reflection, diffraction, refraction, and focusing of shock waves in gases and liquids are sequentially displayed. Though the images themselves are self-explanatory, brief explanations of the experimental conditions are included, so as to facilitate analysis and numerical reproduction of the image data. In addition, the book presents interferometric observations of underwater shock wave/bubble interactions, and highlights the multifaceted applications of shock wave phenomena to medicine and industry. Given its scope, the book offers a unique resource for students and researchers who are interested in shock wave phenomena. However, the content has also been specifically prepared for the benefit of readers who are interested in gas dynamics and medical applications of shock waves, and are looking for reliable experimental images.