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"ABSTRACT

Recently, there -is a rapidly grow in the field of optical fiber communications, particularly in the technology of fiber waveguide which is used as transmitting media or communication lines. 'Due mayor problem in optical waveguide systems is the coupling loss in connectors or couplers for the purpose of gaining maximum coupling efficiency. This research is dedicated to obtain an efficient wavegui de devi ce by studyi ng the applicability of cone-shaped fiber end-face as fiber star coupler without any complement element. Light power from one end-face of fiber was directly coupled to another cone-shaped fiber end-face. The first step of this study was the process of cone-shaping for graded-index fibers. The result was used as coupling elements in an experimental star coupler. The evaluation of the result is carried out based on the concept of radiation pattern of electromagnetic field in cone-shaped end-face of fibers- It. is concluded that the experimental star coupler is predicted to be useful with some improvement in choosing fiber-core diameter. matching the size of the coupled fibers and aligning the suitable axes of the outgoing fibers.;Recently, there -is a rapidly grow in the field of optical fiber communications, particularly in the technology of fiber waveguide which is used as transmitting media or communication lines. 'Due mayor problem in optical waveguide systems is the coupling loss in connectors or couplers for the purpose of gaining maximum coupling efficiency. This research is dedicated to obtain an efficient wavegui de devi ce by studyi ng the applicability of cone-shaped fiber end-face as fiber star coupler without any complement element. Light power from one end-face of fiber was directly coupled to another cone-shaped fiber end-face. The first step of this study was the process of cone-shaping for graded-index fibers. The result was used as coupling elements in an experimental star coupler. The evaluation of the result is carried out based on the concept of radiation pattern of electromagnetic field in cone-shaped end-face of fibers- It. is concluded that the experimental star coupler is predicted to be useful with some improvement in choosing fiber-core diameter. matching the size of the coupled fibers and aligning the suitable axes of the outgoing fibers."

"The rapidly increasing concern of non-ionizing microwave radiations affecting human health adversely has been gaining much of attention. a large volume of research studies have been published in the past decade. most of the previous review literature in this key research area are limited to a certain domain leading to questionable gaps that still need to be filled. this paper, therefore, investigates and analyses all possible gaps, which are left in recent literature related to this issue and aims to provide an inclusive up-to-date overview of evidences and epidemiological studies on different parts of human body, in both adult and children. based on the literature review, it is evident that the rise in the Specific Absorption Rate (SAR) above its maximum value due to the exposure from non-ionizing radiation can cause severe effect on human body such as a cataract formation in the eye, a shortfall in sperm count in men etc. specific Anthropomorphic Mannequin (SAM) model, which is used as a certification technique for cell phone, is found to be overestimating the adult and child head exposure by using same geometric model for child and adult head types. It has also been observed that the electromagnetic radiation has both positive and negative effect on the human life, depending on the context of its application. It is envisaged that human can gain from the positive side and avoid the negative effect. A step by step example of numerical simulation model is illustrated to support future researchers in developing further work in this research area."

"The dualistic theory is utilized as the framework for our analysis of the emerging spatial pattern of development in Nigeria’s Federal Capital Territory. The analysis is carried out using the principal axis method of factoring out data set. Furthermore, the scores of the extracted orthogonal factors are mapped and interpreted in spatial terms. The space economy of our study is observed to conform with the dualistic theory in two major ways. It is suggested that the development of an asymmetrical relationship between the two structural components of the observed spatial dualism must be prevented by adopting appropriate regional development policies."

"This study tries to detremine the concertration of sea surface microlayer from different coastal environments (Port Dickson, Negeri Sembilan and Perhentian Island,Terengganu)...."

"Radiografer secara umum mempunyai tugas dan tanggung jawab untuk melakukan pemeriksaan pasien secara radiografi meliputi pemeriksaan untuk radiodiagnostik termasuk kedokteran nuklir dan ultrasonografi (USG) dan melakukan tindakan proteksi radiasi dalam mengoperasikan peralatan radiologi. Penelitian ini bertujuan memprakirakan risiko pajanan radiasi sinar-X pada pekerja radiasi di Departemen Radiologi RSUPN Cipto Mangunkusumo. Dalam perhitungan prakiraan risiko pajanan radiasi sinar-X, dosis pajanan radiasi sianr-X radiografer diperoleh dari hasil pengukuran film badge. Data pola aktifitas (lama kerja, frekuensi pajanan dan masa kerja) diperoleh berdasarkan hasil wawancara pada 35 radiografer di Departemen Radiologi RSUPN Cipto Mangunkusumo. Berdasarkan perhitungan yang dilakukan, nilai rata-rata Excess Cancer Risk (ECR) lifetime (4,8E-2) dan realtime (1,9E-2). Karena secara teoretis karsinogenisitas tidak mempunyai nilai ambang atau non threshold, maka prakiraan risiko dinyatakan unacceptable (dosis tidak dapat diterima) bila ECR < E4. Kisaran angka E-4 diperoleh dari nilai default karsinogenistas yang digunakan oleh US-EPA (1990). Berdasarkan perhitungan ECR lifetime dan ECR realtime diperoleh gambaran prakiraan risiko efek karsinogenik yang terjadi pada radiografer di Departemen Radiologi RSUPN CM, dinyatakan aceptable pada risiko kanker baik pada ECR lifetime maupun realtime.

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Radiographer in general have a duty and responsibility to audit includes examined patients for radiodiagnostic including nuclear medicine and ultrasonography (USG), and radiation protection in radiology and operating equipment. This study aims to estimated the risk of X-ray radiation exposure to radiographer in the Department of Radiology RSUPN Cipto Mangunkusumo using Environmental Health Risk Analysis (ARKL). In calculating the estimated risk forecasts ARKL, risk of X-ray radiation exposure dose radiographer obtained from measurements of the film badge. Data patterns of activity (duration of work, frequency of exposure and years of work) obtained based on the results of a survey of 35 radiographers in the Department of Radiology RSUPN Cipto Mangunkusumo.

Based on the calculations performed, the average value of Excess Cancer lifetime Risk (ELCR) is 4,8E-2 and the value of Excess Real-time Cancer Risk (ERRC) the average is 1,9E-2. Because theoretically carcinogenicity has non-threshold value, then the forecast is declared unacceptable when ECR < E-4. Range of numbers obtained from the E-4, carcinogenicity default values used by the US-EPA (1990). Based on the calculation of the ELCR and ERCR forecasts illustrate the risk of carcinogenic effects that occur in the radiographers in the Department of Radiology RSUPN CM, acceptable on cancer risk both in the ELCR and ERRC."

"Energi merupakan unsur yang selalu berhadapan dengan manusia dalam kehidupan sehari-hari, yang terdiri dari beberapa jenis, seperti energi potensial, energi mekanik, energi kinetik dan lainya. Kalor juga merupakan energi yang sangat dibutuhkan kemampuan untuk memanfaatkan energi ini. Kalor juga memiliki sifat dapat berpindah dari suatu tempat ke tempat lainya, salah satunya adalah radiasi. Radiasi kalor merupakan sumber energi yang sangat baik untuk dimanfaatkan karena sifatnya yang mampu berpindah tanpa adanya perantara. Namun radiasi juga dapat membahayakan jika fluks kalor yang dipaparkan sangat besar yang mampu memicu penyalaan api pada objek yang terpapar.untuk menghindari hal tersebut maka perlu diantisipasi dengan salah satu cara melakukan pemetaan radiasi kalor pada suatu area tersebut. Pemetaan yang dilakukan terdiri dari beberapa faktor seperti jarak, offset, elevasi dan sudut pandang. Tentu saja jika sumber panas berada pada area fluida menyebabkan adanya pengaruh konveksi pada fluks kalor yang terukur. Kalor yang dihasilkan akan mengubah karakteristik udara disekitar objek yang dipaparkan dan akan membentuk sebuah lapisan batas yang memiliki ketebalan sesuai dengan karakteristik aliran kalor.

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Energy is always connected with human life in every day, which is like potential energy, mechanical energy, kinetic energy and others. Heat is also a kind of energy, that rsquo s needed skill and capabilites to use this energy. Heat also has properties that can devolve to others place, one of that is radiation. Heat radiation is a very good energy to be exploited because of the nature characteristics of radiation is being able to move without a medium. However, radiation can also be dangerous if the heat flux is very large which can be triggered ignition fire of the object. To keep those things it is necessary to anticipate, one of them is to make a mapping of radiation in the area. Mapping consists of several factors such as distance, offset, elevation and view factor. Of course, if there is heat in the fluid region it will cause influence of convection in measurable heat flux. The heat produced of the heater will change the properties of air around exposed object and will form a layer that has a thickness according to the heat flow."