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"DETERMINATION OF MATERIAL AND ITS THICKNESS FOR Cs - 137 GAMMA SOURCE SHEILDING. Its has been determined the sheilding material and its thickness necessarily conducted due to every material will have different half - thickness characteristics, and by the selection a suitable material and its thickness will be obtained...."

"The characterization of shield panel of X-ray radiation was carried out. Aim of the characterization is to find the panel in that qualities comply with the reference, so the panel can be used for the folding door of nuclear medical...."

"On transmission line towers can be installed fiber optic cables for control of power supplies and data communication. To avoid the damages of fiber optic cables cause of the eject of climate and environment, the shielding that used on fiber optic cables was made _#am the metal. With using this shielding, the electric field that produced from transmission line will be ejected With this shielding; the electric field that produced from transmission line will be higher or lower. There for, we must know the eject of using the fiber optic cables shielding to the electric field that produced from transmission line that installed fiber optic cables. This is useful to determinating the free room from the transmission line."

"Pelepasan ion Al dan V pada produk komersial implan medis Ti-6Al-4V dapat menyebabkan permasalahan kesehatan karena bersifat toksik. Selain itu modulus elastisitas implan medis Ti-6Al-4V relatif lebih tinggi dari modulus elastisitas tulang manusia, sehingga dapat menyebabkan fenomena stress shielding effect. Oleh sebab itu, dilakukan pergantian unsur Al dan V dengan unsur Nb dan Mo yang tidak bersifat toksik. Kemudian ditambahkan kembali unsur low cost Mn dengan variasi 2%, 4%, dan 6% untuk mensubtitusi unsur Nb dan Mo yang termasuk unsur yang relatif mahal. Unsur Nb, Mo dan Mn merupakan unsur penstabil fasa β yang memiliki nilai modulus elastisitas lebih rendah dibanding Ti-6Al-4V. Fasa β merupakan fasa yang stabil pada suhu tinggi, sehingga dilakukan perlakuan panas untuk menstabilkan fasa ini dengan homogenisasi pada 3, 6 dan 12 jam untuk mengetahui pengaruhnya. Hasil penelitian membuktikan bahwa penambahan komposisi Mn pada paduan menyebabkan penurunan efek toksisitas dengan menstabilkan pembentukan lapisan pasif pada permukaan logam. Lalu, didapatkan perolehan fraksi volume fasa β yang meningkat seiring penambahan komposisi unsur Mn sehingga didapatkan nilai modulus elastisitas yang menurun. Pada proses perlakuan panas, waktu 6 jam merupakan waktu yang optimal untuk memperoleh fasa β yang lebih homogen dengan mengeliminasi sisa fraksi volume fasa α yang ada pada paduan. Dapat disimpulkan penambahan komposisi unsur paduan Mn akan meningkatkan perolehan fasa β dan perlakuan panas perlu dilakukan untuk mendapatkan fasa β yang stabil dan homogen, sehingga didapatkan paduan yang lebih inert dengan nilai modulus elastisitas mendekati nilai modulus elastisistas tulang manusia.

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The release of Al and V ions in commercial products of Ti-6Al-4V medical implants can cause health problems because they are toxic. In addition, the modulus of elasticity of Ti-6Al-4V medical implants is relatively higher than the modulus of elasticity of human bones, so that it can cause stress shielding effect phenomena. Therefore, al and V elements are replaced with Nb and Mo elements which are not toxic. Then the low cost Mn element was added with variations of 2%, 4%, and 6% to substitute Nb and Mo elements which included relatively expensive elements. Nb, Mo and Mn elements are β phase stabilizers which have a modulus of elasticity lower than Ti-6Al-4V. The β phase is a phase that is stable at high temperatures, so heat treatment is carried out to stabilize this phase by homogenization at 3, 6 and 12 hours to determine its effect.

As a result, the addition of the Mn composition to the alloy causes a decrease in the effect of toxicity by stabilizing the formation of a passive layer on the metal surface. Then, the acquisition of β phase volume fraction obtained increases with the addition of the composition of the element Mn so that the modulus of elasticity decreases. In the heat treatment process, 6 hours is the optimal time to obtain a more homogeneous β phase by eliminating the remaining α phase volume fraction present in the alloy.

It can be concluded that the addition of Mn alloy element composition will increase β phase acquisition and heat treatment needs to be done to obtain a stable and homogeneous β phase, so that more inert alloys with elastic modulus values ​​are obtained close to the human bone elastic modulus."

"Synthesis and Monte Carlo simulation of improved concrete composites as x-ray/gamma ray shielding materials were performed. Samples of shieldings were synthesized using the base materials of Portland-type cement concrete with fillers of alloy steel, Co, Mn, and Cr, mixed separately as additives. The samples were characterized using Scanning Electron Microscopy-Energy Dispersive X-ray Spectrometry (SEM-EDS) to determine the constituent elements quantitatively. Linear attenuation coefficients of the samples were measured in the experiments and also simulated using Monte Carlo transport code MCNP5 in order to evaluate their shielding performance. The results of the experimentation and computer simulation reveal concrete with alloy steel added as having the best shielding properties, although concrete with other fillers added also exhibited enhanced shielding performance. It was demonstrated that 6.06 w% of fillers enhanced the x-ray/gamma ray shielding capability of ordinary concrete composites by improving their attenuation coefficient values by 40–60%."

"In modern medicine, a radiation scans is an very important examination tool for making a diagnosis and subsequent treatment plan. Among the range of medical examinations, Computed tomography (CT) is being performed in an increasing number of cases and a CT scan uses the most radiation of any diagnostic exam. On the other hand, radiation protection during scanning is not typical for bodily regions other than those designated for examination. Therefore, the aim of this study was to develop a lead-free fused radiation shielding fiber (RSF) and to evaluate its effectiveness with a view to reducing radiation exposure to only the effective dose or less in a CT scan by means of a multilayer structural coating. A GE High Speed Advantage Spiral CT was used to conduct measurements using a FH-40G (Eberline, USA) proportional digital counter survey meter. In a brain CT scan, abdominal CT scan, and knee CT scan, two-way ANOVA was used to analyze the changes in radiation dosage and to examine the correlation based on body parts and thickness of the RSF. In addition, when significant results were obtained, a Duncan post hoc test was used to examine the difference depending on each condition. In the brain CT scan, the highest exposure to secondary radiation was measured in the chest, which was closest in distance. The use of a 3- mm shielding fiber resulted in a shielding effect of approximately 65% shielding effect compared to the initial exposure dose. In the abdominal CT scan, no exposure dose was detected in the head area, which had been shielded with the 3-mm shielding fiber. In a knee CT scan, 1-mm shielding fiber was sufficient to demonstrate a shielding effect. The RSF developed in this study may help reduce low-dose exposure to secondary X-rays, such as scattered rays."

"ABSTRAKSemakin banyaknya kegiatan konstruksi pada lahan terbatas menyebabkan jarak antara bangunan satu dengan lainnya sangat dekat. Misalnya pada kasus embankment yang berdekatan dengan suatu bangunan yang sudah ada. Konstruksi embankment ini dapat menyebabkan tanah di bawahnya bergerak sehingga dapat mengganggu tiang-tiang eksisting yang menopang struktur bangunan. Pengaruh tersebut antara lain terjadinya settlement dan lateral soil movement. Komponen terakhir dianggap lebih kritis dampaknya terhadap adjacent piles, khususnya pada kondisi tanah yang lunak yang mengalami tekanan akibat konstruksi embakment sehingga tanah bergerak secara horizontal menekan adjacent piles. Untuk itu perlu diberikan shielding piles pada tanah yang berfungsi meminimalisasi efek embankment terhadap lateral soil movement.

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ABSTRACTIncreasing number of construction activities on a limited land causes distance between the buildings to each other very closely, For example in embankment case adjacent to an existing building. Embankment construction can cause the ground beneath him move that can interfere with the existing pillars that support the structure buildings. Influences include the settlement and lateral soil movement. The last component is considered more critical impact on the adjacent iles, especially in soft ground conditions that have pressure due to construction so that the soil mbakment moves horizontal pressing adjacent piles. It needs to be given to shielding Pile on the ground that serves to minimize the effects of Embankment on lateral soil movement. "

"Pelaksanaan konstruksi embankment atau penyimpanan material industri pada suatu lahan menimbulkan pergerakan tanah secara lateral. Pergerakan ini membuat material tanah dibawahnya mengalami gangguan berupa terganggunya tiang yang berdekatan (adjacent pile). Pergerakan tanah secara lateral tersebut perlu diketahui dampaknya terhadap tiang-tiang yang ada dan juga perlu diketahui suatu soil support yang dapat mengurangi efek pergerakan tanah secara lateral tersebut. Salah satu soil support yang mendukung adjacent pile dalam menahan pergerakan tanah tersebut adalah shielding piles. Penelitian difokuskan pada nilai tekanan lateral tanah ultimate terhadapadjacent pile serta efek penggunaan shielding piles pada reduksi nilai tekanan tanah lateral ultimate. Hasil penelitian pada group tiang 2x1, 2x3, 2x5, 2x7 tanpa group tiang memperlihatkan penurunan nilai tekanan lateral tanah pada group tiang yang semakin besar. Nilai tekanan lateral tanah near pile lebih besar dari pada far pile. Untuk group tiang 2x5 dan 2x7 nilai tekanan lateral tanah terkecil terjadi pada spasi Sh=2.5w; Sv=2.5w. Hasil penelitian group tiang 2x7 dengan shielding piles sisi near pile menampilkan reduksi terbesar terjadi pada sisi near pile. Reduksi terbesar terjadi pada penerapan shielding piles dengan jarak 2.5w dari tiang ukuran 100%w. Nilai tekanan lateral tanah rata-rata terkecil terjadi pada spasi Sh=2.5w; Sv=2.5w. Pada penggunaan shielding piles sisi near pile dan far pile untuk group 2x7 menampilkan reduksi terbesar terjadi pada sisi near pile dan far pile. Reduksi terbesar terjadi pada penggunaan shielding piles dengan jarak 2.5w dari tiang ukuran 100%w. Dan nilai terkecil terjadi pada spasi Sh=2.5w; Sv=2.5w.

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The construction activities of embankment or industrial material storage cause lateral soil movement of the land. This movement causes disturbance to the soil beneath that affects the adjacent pile. The effect of lateral soil movement and a soil support that reduce its effect need to be known. Shielding piles is known to be a soil support that reduces the effect. This research is focused on the value of ultimate lateral soil pressure to the adjacent pile and effect of shielding pile in reducing the ultimate lateral soil pressure. The results of pile group 2x1, 2x3, 2x5, and 2x7 without pile group indicates decreasing value of lateral soil pressure of bigger pile group. The smallest lateral soil pressure value is obtained on pile group 2x5 and 2x7 with spacing of Sh=2.5w, Sv=2.5w respectively. On the application of shielding pile on near pile side for pile group 2x7, biggest reduction is observed on the near pile side respectively. The biggest reduction happened on applying shielding pile with spacing of Sh=2.5w of 100%w pile size. The smallest average of lateral soil pressure is observed at spacing of Sh=2.5w, Sv=2.5w. On the application of shielding pile on near pile and far pile side for pile group 2x7, biggest reduction is observed on the near pile and far pile side respectively. The biggest reduction happened on applying shielding pile with spacing of Sh=2.5w of 100%w pile size. The smallest average of lateral soil pressure is observed at spacing of Sh=2.5w, Sv=2.5w."