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"Many applications and industrial processes require very low cooling temperature, such as cold storage in the biomedicalfield, requiring temperature below -80 °C. However, single-cycle refrigeration systems can only achieve the effectivecooling temperature of -40 °C and, also, the performance of the cycle will decrease drastically for cooling temperatureslower than -35°C. Currently, most of cascade refrigeration systems use refrigerants that have ozone depletion potential(ODP) and global warming potential (GWP), therefore, in this study, a cascade system is simulated using a mixture ofenvironmentally friendly refrigerants, namely, carbon dioxide and a hydrocarbon (propane, ethane or ethylene) as therefrigerant of the low temperature circuit. A thermodynamic analysis is performed to determine the optimal compositionof the mixture of carbon dioxide and hydrocarbons in the scope of certain operating parameters. In addition, aneconomic analysis was also performed to determine the annual cost to be incurred from the cascade refrigeration system.The multi-objective/thermoeconomic optimization points out optimal operating parameter values of the system, toaddressing both exergy efficiency and its relation to the costs to be incurred."

"Banyak aplikasi dan proses-proses di industri yang membutuhkan temperatur pendinginan sangat rendah, bahkan bidang biomedis membutuhkan cold storage yang mampu mendinginkan hingga temperatur -80°C. Penggunaan sistem refrigerasi siklus tunggal pada aplikasi temperatur sangat rendah menjadi tidak ekonomis karena tinggi nya rasio tekanan dan juga menghasilkan efek pendinginan yang tidak efektif karena rendah nya tekanan evaporasi, sehingga digunakan sistem refrigerasi cascade. Penggunaan refrigeran alamiah, seperti campuran karbon dioksida dan hidrokarbon merupakan alternatif dari penggunaan refrigeran yang mengandung bahan perusak lapisan ozon dan pemanasan global. Pada penelitian ini, dilakukan analisis termodinamika untuk menentukan komposisi campuran karbon dioksida dan hidrokarbon yang optimum. Selanjutnya, dilakukan optimisasi secara termoekonomi untuk menentukan kondisi operasi yang optimum dari sistem refrigerasi cascade, dimana peningkatan efisiensi exergy merupakan sasaran optimisasi secara termodinamika, sedangkan meminimumkan pengeluaran biaya tahunan merupakan sasaran optimisasi secara ekonomi.

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There are many industrial applications and processes in which ultra-low temperature is necessary, even the biomedical preservation that needs cold storage providing temperature about -80°C. The use of single cycle refrigeration system for ultra-low temperature application is economically unacceptable caused by the high pressure ratio and results the ineffective evaporating effect as the low evaporating pressure, hence the cascade refrigeration system is applied. Natural refrigerants, such as carbon dioxide and hydrocarbon will be the alternative solutions of the used of ozon depleting and global warming effect refrigerants. In this research, thermodynamic analysis is applied to decide the optimum composition of the mixtures between carbon dioxide and hydrocarbon. Furthermore, thermoeconomic optimization results the optimum operating conditions of the cascade refrigeration system where the increasing of exergetic efficiency is the thermodynamic objective, while the minimization of the annual cost is the economic objective."

"AbstrakPentingnya proses belajar mengajar guna menghasilkan penerbang TNI yang handal maka perlu suatu edia pembelajaran yang efektif dan efisien serta interaktif terhadap siswa siswa penerbang tersebut. untuk itu perlu dikembangkan suatu media interaktif yang bisa membantu peserta didik dalam memahami materi khususnya materi instrument landing system dan membantu infrastruktur penerbang dalam menyampaikan bahan pelajaran tersebut sehingga diharapkan semua peserta didik nantinya dapat menguasai materi dengan mudah. oleh karena itu pada penelitian kali ini akan dikembangkan suatu media pembelajaran frngan menggunakan multimedia interaktif yaitu mengkombinasikan brebagai unsur media yang terdiri dari teks, grafis,foto, animasi, video, dan suara yang disajikan secara interaktif dalam media pembelajaran untuk materi instrument landing system dengan berbasis adobe flash. untuk menambah kenyamanan dalam belajar, multimedia interaktif ini dilengkapi dengan animasi tentang penggambaran instrument landing system yang disajikan dengan tamplan yang menarik sehingga user dapat dengan mudah memahami materi. untuk menguji seberapa jauh pemahaman user, di lengkapi dengan quiz tentang materi localizer, glide slope dan marken beacon"

"ABSTRAKThis study conducts the energy and exergy analysis of a light-vent pipe which is integrated into attic space. The roof is a shed roof with 30 degrees of inclination angle. The LVP is manufactured from an aluminum sheet with a translucent flat cover and is 0.15 m in diameter. The results show that the test house integrated with the LVP could well transfer heat accumulated in attic space by natural ventilation through the LVP. The natural daylight has an influent to the air mass flow rate corresponding to energy and exergy efficiency. The total energy and exergy efficiencies were 37-67% and 12.3-33%, respectively. In addition, the ceiling heat gain and exergy heat gain performed that, the requirement of space cooling of the house with LVP lower than that the reference house."

"ABSTRAKRice bran oil soapstock (RBOS) is a by-product from the chemical refining process of rice bran oil production. It contains a large amount of -oryzanol. The main objective of this study was to investigate the amount of -oryzanol obtained by solvent extraction using soxhlet apparatus. RBOS was saponified and was then dehydrated and extracted with ethyl acetate. The optimum conditions were determined using response surface methodology (RSM) with a Box-Behnken experimental design (BBD). BBD was used to investigate the effects of three independent variables, namely solid to solvent ratio (w/v), extraction temperature (C), and extraction time (h). The results showed that the most suitable conditions for the extraction of RBOS that can provide the highest yield of -oryzanol (9.04% dry basis) were 1:12 solid to solvent ratio, 70.1C extraction temperature and 7.26 h extraction time."

"Jaringan komputer sangat berguna dalam pekerjaan manusia diantaranya dalam saling berkomunikasi satu sama lain. Oleh karena itu dibutuhkan keamanan jaringan yang berguna dapat menjaga kerahasiaan informasi dan juga menghindari serangan-serangan yang menimbulkan dampak negatif.Pada skripsi ini akan dibahas mengenai bagaimana pengujian dan analisis dalam salah satu tools IDS (Intrusion Detection System) berbasis host atau yang biasa disebut HIDS (Host-Based Intrusion Detection System). HIDS yang digunakan adalah OSSEC karena bersifat Open Source. Pengujian ini bertujuan untuk mencari tahu keberhasilan, response time dan pengaruh OSSEC terhadap performansi jaringan melalui throughput yang didapat. Juga membandingkan OSSEC dengan Suricata dan Honeyd. Hasil dari pengujian terhadap functional test, OSSEC mampu mendeteksi serangan berupa port scanning dan SSHD brute force attack. Pada perhitungan response time, dihitung berdasarkan fitur OSSEC sebagaimana active-response yang mampu memutuskan koneksi terhadap IP penyerang dan response time yang didapat sebesar 2.1397618 detik. Juga OSSEC tidak mempunyai pengaruh yang besar pada performansi jaringan.

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Computer network is very useful in work beings communicate with each other. Therefore network security is needed which will keep the secret of information and also avoid the attacks that inflict a negative impact.

At this final project will discuss about how to test and analysis of one of the IDS (Intrusion Detection System) tools based on host or commonly called HIDS (Host-Based Intrusion Detection System). And HIDS used is OSSEC because it is open source. This test aims to find out the success of OSSEC, response time and influence ossec againt network performance through throughput obtained. Also compare ossec with suricata and honeyd. Results from testing of the functional test, OSSEC is able to detect port scanning attack and SSHD brute force attack. On the calculation of response time, calculated based on the features OSSEC as active-response capable of disconnecting against the attacker's IP and response time obtained is 2.1397618 seconds. Also OSSEC have no great influence on network performance."

"ABSTRAKSince the increasing demand of molasses as raw material for ethanol production in Thailand, the feasibility of applying raw sugar as an alternative raw material for ethanol production is studied in this research. However, although raw sugar has higher sugar content and pure quality than molasses, raw sugar costs are higher than molasses. Thus, it is necessary to evaluate the optimum proportion of raw sugar by considering the value of fermentation efficiency by analyzing the ratio of raw sugar to molasses from 0%:100% to 100%:0%. The results showed that the mixture of raw sugar and molasses in Experiment No.1 at a ratio of 20%:80% gained the highest fermentation efficiency at 82.71%. With the addition of enzyme (Experiment No.2), it would enhance the fermentation efficiency to 84.27% at a ratio of 60%:40%. Moreover, by adding enzyme and ferment nutrients (Experiment No.3) it could enhance the fermentation efficiency to 85.98% at a ratio of 80%:20%. These results indicated that the higher amount of applying raw sugar, the more fermentation efficiency in ethanol production. Furthermore, the economic results shown that even though a ratio of 80%:20% from Experiment No.3 had the highest fermentation efficiency, a ratio of 20%:80% presented the best economic result (profit) with high fermentation efficiency (around 85%). Moreover, when the prices of raw sugar and molasses were changed, the Experiment No.3 had more appropriate operation than Experiment No.1 and No.2, because the Experiment No.3 provieded the best economic results with any conditions."

"ABSTRAKDue to the situation of increasingly severe PM-10 pollution that adverse affects on humans and environment across the globe, the purpose of this work is to implement the optimal PM-10 forecast model as a basis tool in process of planing/controlling air pollution and public awareness apply to Chiang Mai city and surrounding area, in Northern Thailand. Accurate and reliable forecasting model are our goal. Due to the fuzzy feature of PM-10 as well as the high correlated hotspot during open burning and forest fires season of this study area, the adaptive neuro-fuzzy inference system (ANFIS)-based forecasting model has been statistically implemented as tool for daily mean PM-10 concentration estimation. For achieving more efficient and realistic model, the hotspot count among other meteorological parameters is utilized as the exogenous variable through the design and optimization. The forecasting performance evaluated in terms of the tradeoff between accuracy with regard to RMSE and MAE, computational complexity with respect to the multiplications per an execution, and reliablity through Akaike criterion information (AIC) is used to assess the forecast models. As forecasting results, the proposed ANFIS model with an integrated hotspots outperforms the other existing models."

"ABSTRAKHigh annealing temperature - random amplified polymorphic DNA (HAT-RAPD) marker was used to identify and investigate the genetic relationship among 15 Paphiopedilum species of Venus slipper. The total of 72 primers was screened and 16 primers could be used for DNA amplification with clear amplified products to construct DNA fingerprints. The total of 248 polymorphic bands was found. A dendrogram, which constructed from the polymorphic bands using UPGMA by the NTSYS program, showed genetic similarities among 15 Paphiopedilum species with similarity coefficients ranging from 0.252 to 0.624. The orchids were classified into 3 clusters. These results indicated that the HAT-RAPD markers are capable to specify Paphiopedilum, and can be used in the breeding program and for genetic resource conservation in the future."