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Abstrak :
Infestasi tuma kepala sering terjadi pada anak-anak yang tinggal di lingkungan padat penghuni misalnya di pesantren. Pengetahuan mengenai cara penularan tuma kepala diharapkan dapat menurunkan keparahan infestasi tuma. Tujuan penelitian ini adalah mengetahui hubungan tingkat keparahan infestasi dengan pengetahuan mengenai penularan tuma kepala pada santriwati di sebuah pesantren di Jakarta. Desain penelitian ini adalah studi potong lintang yang dilakukan pada bulan Maret 2014. Subyek penelitian adalah semua santriwati yang hadir saat pengumpulan data dan bersedia berpartisipasi. Data dikumpulkan dengan kuesioner yang berisi lima pertanyaan mengenai pengetahuan santriwati tentang penularan tuma kepala dan pemeriksaan kepala untuk menilai keparahan infestasi. Data dianalisis menggunakan SPSS versi 20 dan diuji dengan chi-square. Hasil penelitian menunjukan semua anak perempuan (n=74) terinfestasi tuma kepala dengan kasus infestasi parah 24,3%. Sebagian besar santriwati (49/66,2%) memiliki pengetahuan rendah mengenai penularan tuma kepala. Uji chi-square tidak menunjukkan perbedaan signifikan pada tingkat keparahan infestasi antara santriwati yang memiliki tingkat pengetahuan baik dan kurang. Disimpulkan keparahan infestasi tuma pada santriwati tergolong tinggi dan tidak berhubungan dengan tingkat pengetahuan mengenai penularan tuma kepala. ......Head lice infestation commonly found in children which live in overcrowded areas such as in pesantren. Having knowledge on head lice transmission is expected to decrease the severity of head lice infestation in children in pesantren. The aim of this research is to find the relationship between severity of infestation and level of knowledge on transmission of head lice in female students in a pesantren in Jakarta. The study design was cross-sectional study which is held on March, 2014. The subjects of research were all female students that presented on the day of data collection and were willing to participate. Data were collected through questionnaire that consisted of five questions regarding level of female students? knowledge on head lice transmission and physical examination that assessed the level of head lice infestation severity. Data were analyzed through SPSS version 20 and chi-square test. The result showed that all female students (n=74) infested by head lice with 24.3% of infestations were severe cases. Majority of female students (49/66.2%) had poor knowledge on head lice transmission. Chi-square test did not reveal significant difference on severity of head lice infestation between female students with good and poor knowledge on head lice transmission. As a conclusion, the severity of head lice infestation in female students was considered high and was not related to the level of knowledge on head lice transmission.;

Abstrak :
Wireless power transmission is being investigated as a means to operate tiny medical devices such as the capsular endoscope, which is able to exist for a long period during diagnostic procedures within the body. In this paper, we examine the wireless power transmission to a capsular endoscope by electromagnetic waves to show its usability for medical applications. A modified helical antenna inside the endoscope is proposed as a power receiving antenna, operating at 915 MHz. By calculating a maximum received power in the stomach using such antenna, the results show that adequate power can be well received.

Abstrak :
Aliran dua fase adalah bagian dari aliran multi fase yang dibedakan berdasarkan pada aliran fasenya (likuid - gas; solid - likuid; gas - solid), arah aliran dan posisi pipa (vertikal, horizontal dan miring). Penelitian eksperimen disini adalah untuk mendapatkan pola aliran konveksi paksa pada pipa horizontal khusus aliran dua fase yang berasal dari satu komponen. Berdasarkan daya heater yang bervariasi (342 watt sampai dengan 2070 watt) dan kapasitas aliran yang bervariasi 30 1/jam dan 60 1/jam, didih nukleat mulai terjadi pada laju aliran 30 1/jam dengan daya heater 2070 watt. Dari pengamatan pada pipa transparan dapat dilihat adanya pola aliran tertentu, yaitu aliran peralihan berupa kantung gas dan aliran sumbat likuid. Dari analisa perhitungan kualitas uap (xi) yang tercapai adalah 0,086; 0,102; 0,11; 0,116 , sedangkan fraksi hampa (a) yang tercapai adalah 0,879; 0,885; 0,888; 0,889. Dengan menggunakan diagram Taitle dan Dukler dapat dibuktikan aliran adalah aliran kantung gas dan aliran sumbat likuid. ...... Two-phase flow is a part of multi-phase flow that is distinguished according to its flow phases (liquid-gas, solid-liquid and gas-solid), flow directions (concurrent and countercurrent) and pipe positions (vertical, horizontal or inclined). The objectives of this research were to obtain the configuration of the internal forced convection flow in horizontal pipe particularly two-phase flow from one component. The experiment was conducted at variable heater power (342 Watt until 2070 Watt) and the variable capacity of water flow were 30 l/hr and 60 l/hr. Boiling happened at flow rate of 30 l/hr and heater power was 2070 Watt. The research was conducted by using transparent pipe and could be seen a certain pattern flow were intermittent flow like plug flow and slug flow. By calculation analysis the result showed that the quality of gas mass flow (x1) were 0.086;0.102;0.11;0.116. The void fraction (a) were 0.879 ; 0.885 ; 0,888 ; 0.889. By using Taitel and Dukler diagram could be proved that the flow were plug flow and slug flow.

Abstrak :
Dalam tesis ini diajukan sistem gabungan multicarrier code-division multiple-access (Multicarrier CDMA) dengan skema Pure Aloha (P-Aloha) dan Slotted Aloha (S-Aloha), yang disebut multicarrier CDMA P-Aloha dan multicarrier CDMA S-Aloha. Analisa terhadap kedua sistem dilakukan terhadap salah satu parameter kinerja sistem yaitu throughput. Dalam sistem multicarrier CDMA P-Aloha dan multicarrier CDMA S-Aloha, data mula-mula dikonversi dari serial menjadi paralel. Data tersebut kemudian dimodulasi dengan direct sequence spread-spectrum (DS-SS) menggunakan kode penyebar yang spesifik pada setiap user, dan semua sinyal DS tersebut ditransmisikan secara paralel pada subcarrier yang berbeda-beda. Setelah dikodekan, data dikirim secara acak untuk sistem multicarrier CDMA P-Aloha, sedangkan pada multicarrier CDMA S-Aloha data dikirim pada permulaan time-slot sesuai mekanisme sistem S-Aloha. Hasil penelitian menunjukkan bahwa kedua sistem memiliki throughput yang tinggi untuk transmisi sinyal dengan laju tinggi, dan multicarrier CDMA S-Aloha memiliki throughput yang lebih tinggi daripada multicarrier CDMA P-Aloha. Hasil penelitian juga menunjukkan bahwa throughput kedua sistem semakin tinggi dengan meningkatnya jumlah subcarrier dan panjang kode single-carrier yang digunakan, sementara peningkatan panjang subpaket menurunkan throughput kedua sistem. Multicarrier CDMA Aloha memiliki throughput yang lebih baik dari CDMA Aloha.

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This thesis proposes integrated systems consisting of multicarrier code-division multiple-access (Multicarrier CDMA) with Pure Aloha (P-Aloha) and Slotted Aloha (S-Aloha) schemes, named multicarrier CDMA P-Aloha and multicarrier CDMA S-Aloha, respectively. The performance analysis of both systems is stated as throughput, Multicarrier CDMA Aloha is proposed to improve the performance of CDMA Aloha. In multicarrier CDMA P-Aloha and multicarrier COMA S-Aloha the initial data is serial-to-parallel converted to a number of lower rate data streams. Each stream which consists of a part of the initial data called sub-packet will be then direct sequence spread-spectrum modulated using specific spreading code for each user, and all the DS-SS signals are transmitted in parallel on different subcarriers. The coded data is sent randomly in multicarrier CDMA P-Aloha system, whereas in multicarrier CDMA S-Aloha, the data is sent at the beginning of the time-slot according to the mechanism of S-Aloha system. Results show that both systems have high throughput for high bit rate signal transmission, and multicarrier CDMA S-Aloha outperforms multicarrier CDMA P-Aloha. It is also shown that the throughput of both systems improves as the number of subcarriers and the length of single-carrier code increase, while the increase of subpacket length degrades the throughput of both systems. Multicarrier CDMA Aloha has better performance compared to CDMA Aloha.

Abstrak :
Emisi asap (smoke) merupakan polutan utama pada mesin diesel. Smoke dihasilkan oleh pembakaran akibat kekurangan oksigen. Hal tersebut kebanyakan terjadi pada inti (core) spray yang mempunyai λ < 0,8. Secara tradisional pengurangan emisi smoke dapat dicapai dengan cara modifikasi sistem bahan bakar, geometri mesin, kontrol dari mesin atau menggunakan kombinasi dari ketiga cara diatas. Metode yang lain yang sering digunakan adalah menggunakan bahan bakar reformulasi atau biodiesel yang mengandung oksigen. Hal ini karena penambahan oksigen didalam bahan bakar menyebabkan inti dari spray menjadi tidak terlalu kaya, sehingga memungkinkan penurunan emisi smoke. Beberapa studi telah membuktikan hal ini, namun mekanisme kerja oksigen dalam hal ini belum begitu jelas. Oleh karena itu studi kali ini berusaha untuk mempelajari lebih jauh peranan dan efek oksigen dalam proses pembakaran dengan cara ekperimen dengan menggunakan bahan bakar solar murni dan dibandingkan dengan bahan bakar campuran solar-biodiesel. Pada studi kali ini proses pembakaran didalam ruang bakar dipelajari dengan menggunakan analisa heat release, tekanan puncak silinder dan waktu tunda pembakaran. Dan hasil penelitian dengan variasi beban nampak bahwa pengurangan fraksi pembakaran difusi menghasilkan pengurangan emisi smoke. Hasil eksperimen memperlihatkan adanya hubungan antara durasi Mixing controlled combustion dengan emisi smoke yang dihasilkan. Durasi pembakaran pada fase tersebut memegang peranan penting dalam penurunan emisi smoke. Analisa heat release menunjukkan penggunaan bahan bakar solar-Biodiesel dalam hal ini menggunakan Metyl Ester 30 % berat, mempersingkat waktu pembakaran pada mixing controlled combustion dan memperpanjang lama pembakaran di late combution.

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Smoke emission is the major pollutant from diesel engine. Smoke is emitted in diesel engine because fuel injected into combustion chamber burns with insuffient oxygen. The process takes place in the spray core that has λ < 0,8. Reductions of diesel engine emissions have traditionally been achieved through modification fuel system, combustion chamber geometry, engine control or combination of those. Another method to decrease smoke emissions is by using reformulating diesel fuel or biodiesel that contains oxygen in the fuel. The additional oxygen content into fuel would make a leaner mixture in the core spray. Therefore oxygenated diesel fuel offers the possibility of reduction particulates matter emissions significantly. The mechanism by which oxygen content leads to particulates matter reductions is still unclear. In this study author would attempt to further study about the oxygen effect in combustion process experimentally using diesel fuel and of mixture diesel fuel-biodiesel. The study was conducted using in-cylinder pressure analysis to obtain heat release, peak pressure, and ignition delay. The results load variation experiment so that the smoke would increase with the diffusion combustion fraction. The experiment results show a relationship between mixing controlled combustion durations with the smoke emitted from the engine. The duration in this phase combustion plays important role on smoke reductions. Heat release rate shows that using mixture of diesel fuel-biodiesel, in these case methyl ester sawit 30% by mass, would decrease premixed and mixing controlled combustion durations and increase late combustion duration.

Abstrak :
Industri pertanian umumnya adalah industri kecil, dimana tenaga kerja yang bekerja pada industri tersebut tingkat pendidikannya sangat rendah sehingga sulit untuk berkembang dan kesadaran akan mutu sangat rendah. Dalam penelitian ini peningkatan kualitas dilakukan dengan perlakuan panas yang pemanasannya dilakukan bersama-sama dengan proses pembentukan pegangan cangkul. Perlakuan panas dilakukan dengan pemanasan sampai suhu austenit dengan variasi suhu, 900°C, 1000°C dan 1100°C, variasi penahanan 30 menit, 45 menit dan 60 menit. Proses pendinginan dengan menggunakan media pendingin air dan oli serta metode pendinginan dicelup sebagian dan dicelup seluruhnya. Berdasarkan hasil penelitian diatas dilakukan percobaan tahap dua yaitu dengan pemanasan pada arang batok kelapa selama 60 menit, 75 menit, 90 menit dan 105 menit, kemudian dicelup kedalam media air. Dari hasil penelitian didapatkan bahwa dengan pemanasan sampai 900°C, dan penahan selama 30 menit kemudian dicelupkan kedalam air mendapat kekerasan 171 BHN atau naik 50 %. Pemanasan menggunakan dapur listrik dengan suhu penahanan 1000°C, selama 45 menit kemudian didinginkan dengan oli menghasilkan kekerasan tertinggi 143 BHN, dan dengan pemanasan di arang kayu selama 75 menit mendapatkan kekerasan tertinggi yaitu 187 BHN atau naik sebesar 64 %. Biaya yang diperlukan untuk perlakuan panas Rp.890,- tiap cangkul. Proses perlakuan panas dilakukan sebelum pengerjaan akhir.

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Agriculture industry is generally a small industry that the labors who work in the industry have low education so that wake difficultly to develop and have low consideration in quality. In this research quality increases done by heat treatment which is conducted together with process of hoe handle forming. Heat treatment is performed variously with heating at austenite temperature of 900°C, 1000°C and 1100°C for 30, 45, 60 minutes. Cooling process is done in cool water and oil. The cooling method is done by sinking partly and wholly. Based on the above research, the second try is conducted by heating on coconut shell for 60,75, 90 and 105 minutes. Then, it is cooled in cool water. The research result that heating at approx, 900 °C for 30 minutes, then cooled in cool water is gained a hardness of 171 BHN or 50 % increases. Heating using an electric furnace at 1000 °C for 45 minutes, then cooled with oil result a highest hardness of 143 BHN. Heating using charcoal for 75 minutes is gotten a highest hardness of 187 BHN or 64 % increases. Cost spent for this heat treatment is Rp 890,- each hoe. Process of heat treatment is done when the finishing work will end.

Abstrak :
The advantages optical fiber in communication field are widely utilized in developing steps from electrical communication to optical communication. Optical fiber communication promise extremely high data rate over long distance transmission without needing to amplify and retransmit along the way. It is well understood that if frequency of the transmitted signals. is increased some problems such as electromagnetic interferences. crosstalk and signal distortions will appear. Those difficulties can. be solved or eliminated by using optical fiber cable. instead of copper cable. Optical fiber used to transmit and to receive information signal mutinously was usually separated in difference fibers for transmitting and receiving direction. I n this thesis a bi-directional transmission system through a single fiber with same wavelength by the use of rod lenses was constructed. A simple circuit design techniques have been used in order to make transmitter and receiver. To combine and to separate transmitter and receiver in each side to and from the fiber, two quarter-pitch GRIN rod lenses functioning as optical directional coupler was used. The result of the experiment as a model of bi-directional optical communication system shows a good performance with an appropriate reliability. The measurement results of power distribution loss. crosstalk and signal transmission quality that have been evaluated to conclude the entire result.

Abstrak :
Karakteristik medan termal dalam aliran resirkulasi akibat injeksi gas panas pada backward facing step dapat mengindikasikan efektifitas percampuran antara aliran udara dingin yang mengalir melalui kontur tangga (step) dengan gas panas yang diinjeksikan pada jarak dekat dengan step atau mendekati daerah reattachment point. Rasio momentum injeksi, temperatur injeksi dan jarak injeksi dapat menjadi variabel kontrol/kendali terhadap percampuran yang optimal antara aliran udara dingin dan injeksi udara panas setelah melewati backward facing step. Hasil penelitian menunjukkan bahwa injeksi gas panas akan mempengaruhi efektifitas percampuran udara panas dan udara dingin, dengan menaikan rasio momentum injeksi akan diperoleh percampuran yang efektif pada daerah downstream demikian pula dalam arah spanwise pada daerah ini distribusi temperaturnya akan lebih baik. Tetapi efektifitasnya akan menurun pada daerah injeksi. Pada Lf=4H, efektifitas percampuran akan menurun pada daerah downstream karena aliran kalor akan tersebar di daerah free stream akibat dari blocking effect dari aliran injeksi yang lebih kuat terhadap aliran resirkulasi.

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Characteristic of thermal field in re-circulation zone with effect hot gas injection for backward facing step can identify of effectiveness mixing air influence to step and hot gas injection near the step or reattachment point Momentum injection ratio, temperature injection and injection location can variable control of optimal mixing for flow air and hot gas injection after backward facing step. The experiment showing that the increase of the specific momentum ratio can develop to effectiveness mixing of air and hot gas injection in downstream area, included for temperature distribution with span wise direction is well. But the mixing effectiveness can down for injection zone. This phenomenon is quite different to that found in case of injection location near reattachment point (L1= 4H). In this condition, most of the hot gas contained in the injection will distribute to the down stream due to stronger blowing effect of free stream to the re-circulation flow.

Abstrak :
Penelitian terhadap nanofluida telah banyak dilakukan untuk menunjukkan bahwa nanofluida berpotensi untuk perpindahan kalor yang lebih baik Nanofluida adalah campuran antara partikel padat dengan ukuran nanometer dengan fluida dasarnya yakni air. Partikel berukuran nanometer tersebut tersuspensi dalam fluida dasar secara permanen yang dikarenakan adanya efek Brownian pada partikel tersebut. Sebelum nanofluida tersebut diaplikasikan untuk keperluan komersil, diperlukan penelitian lebih lanjut untuk menyempurnakannya. Pada penelitian ini dilakukan penelitian koefisien perpindahan kalor pada proses kondensasi film dengan kondenser vertikal. Dengan variasi laju aliran pendingin, hash penelitian mengindikasikan koefisien perpindahan kalor konveksi nanofluida mengalami peningkatan 12%-19% untuk konsentrasi I% dan peningkatan 23%-33% untuk konsentrasi 4% dari fluida pendingin air.

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Research to nanofluida have a lot of conducted to indicate that nanofluida has a great potency for better heat transfer. Nanofluida is mixture between solid particle of nanosize with the based-fluids. Nano particle suspended in based-fluid permanently which is because of existence of Brownian effect at that particle. Before nanofluids can applicator commercial, needed furthermore advance research to complete it. This research conducted the measurement of heat transfer coefficient film condensation that used vertical condenser with variation the flow rate of cooling fluid The result shows the enhancement of heat transfer coefficient compared to base fluids : 12-19% for I% particles concentration and 23-33% for 4% particles concentration. The enhancement coefficient for condensation, its depend on the thickness of film or condensat that build.