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"Speech compression techniques based on traditional psychoacoustic model have been proposed by many researchers. We have suggested Discrete Wavelet Transform (DWT) supported by the same psychoacoustic model for speech compression. This paper presents a traditional psychoacoustic model to process equal partitions of total bandwidth spectrum of audio signal frequency to reduce redundancy by filtering out the tones and noise masker in speech signal. Here, the uniform filter banks are used for efficient computations and selection of appropriate threshold level for better compression of Discrete Wavelet Transformed coefficients. Daubechies wavelet filter bank is a nonlinear and asymmetric wavelet filter bank. It is equivalent to cochlear filter of human hearing system. The resemblance between Daubechies Filter Bank and our hearing system is used to develop the novel speech coder. Results have shown better performance in terms of compression factor (CF) and Signal-to-Noise Ratio (SNR) as compare to the methods suggested earlier."

"Ruang lingkup dan Cara penelitian : Karbon monoksida, merupakan gas sangat beracun yang dapat dihasilkan oleh kompresor. Kompresor konvensional yang digunakan nelayan penyelam sebagai alat penghasil udara tekan untuk 'media pernafasan' dalam air, dapat memberikan dampak negatif jika digunakan dalam jangka waktu yang lama. Penelitian tentang dampak pemakaian kompresor untuk penyelaman belum pernah dilaporkan, khususnya di Indonesia. Penelitian ini bertujuan untuk mengetahui gambaran rata-rata kadar CO dalam udara kompresor konvensional; prevalensi intoksikasi CO; hubungan antara pajanan CO udara kompresor terhadap peningkatan COHb; besarnya peranan faktor resiko terhadap gambaran hematologi (peningkatan COHb). Parameter gambaran hematologi yang digunakan dalam penelitian ini adalah COHb, Hemoglobin, Hematokrit dan Eritrosit. Disain penelitian adalah dengan menggunakan pendekatan cross sectional terhadap 75 subyek. Pengumpulan data dilakukan melalui wawancara terstruktur, pemeriksaan lisik, dan survey lingkungan kerja (laut). Hasil, kesimpulan dan saran : Subyek terpajan dengan CO udara kompresor rata-rata 4,3 ppm, suatu pajanan yang masih tergolong dalam batas-batas aman untuk penyelaman dengan pemakaian kompresor atau SCUBA. Prevalensi intoksikasi CO dalam penelitian ini berada pada tingkat 'sub level CO intoxication'. Terdapat 9,3 % dari subyek menunjukkan gambaran hematologi bawah normal, dan 90,7 % menunjukkan gambaran normal. Efek hematologi yang merupakan peningkatan COHb mempunyai hubungan secara bermakna terhadap faktor resiko kondisi kompresor dengan O.R 15,58 (95 % C.I: 2,16 - 112,38 ), dan terhadap beban penyelaman dengan O.R 7,65 (95 % C.l : 1,30 - 44,93). Hubungan antara faktor resiko tersebut terhadap peningkatan COHb ternyata didukung pula oleh hasil analisis hubungannya terhadap gambaran hematologi secara bermakna pula. Dengan hasil penelitian ini dapatlah disarankan agar nelayan penyelam selalu memperhatikan kesehatan dan keselamatan kerja dan berpedoman pada buku panduan, antara lain tentang hagaimana cara penggunaan dan perawatan kompresor, memperhatikan arah angin, dan beban penyelaman. Subyek perlu menyediakan waktu untuk aktivitas olahraga, melengkapi menu sehari-hari mereka dengan vitamin, dan sedapat-dapatnya dengan gizi yang haik. Perlu dikembangkan kerjasama dengan instansi Departemen Kesehatan, Departemen Pertanian, gubernur KDKI Jakarta, RSAL Dr. Mintoharjo Jakarta, dan Program Studi Kesehatan dan Keselamatan Kerja Universitas Indonesia atau lembaga pendidikan yang terkait untuk membentuk suatu sistem atau organisasi yang dapat dilimpahkan wewenang serta tanggung jawabnya terhadap kesehatan nelayan penyelam, pembangunan chamber (HBO), riset dan pengembangan di bidang kedokteran kelautan di Indonesia umumnya dan di DKI khususnya.

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Scope and methodology : Carbon monoxide is a highly toxic gas which could be produced by a compressor. Fishermen diver applied it as a compressed air producer, which can be used for sub aquatic breathing. Negative impact might be evoked if is used for a long period. Unfortunately, there has never been reported any study refer to this impact, nor any prevalence of carbon monoxide intoxication published concerning to application of compressor in diving, especially in Indonesia.

The objectives of study is to get a description of carbon monoxide level in air breathing of compressor, prevalence of carbon monoxide intoxication, and analysis of connection between car-bon monoxide exposure and hematologic figure or carboxyhemoglobin elevation. The parameters used in this study are carboxyhemoglobin level in blood, hemoglobin, hematocrit and red blood cell count.

The design of study was cross sectional. Data were collected by structured interview, physical examination, and field survey (offshore) over 75 subjects.

Result, conclusion and suggestion : The subjects were exposed to 4,3 ppm carbon monoxide level in average, within safe range in SCUBA diving or compressor's diving. Prevalence of carbon monoxide intoxication was sub level intoxication. Approximately, 9,3 % subjects had an undernormal figure, and 90,7 % showed normal hematologic figure. Hematological effect, which recorded as carboxyhemoglobin elevation exhibited a significant connection to the risk factors, namely compressor condition, with odds ratio 15,58 ( 95 % C.I: 2,16 - 112,38 ), and diving load with O.R 7,65 ( 95 % C.I: 1,30 - 44,93 ). This connection was supported by analysis of these risk factor with significant connection to hematologic figure.

Referring to this result, it might be suggested to the fishermen diver that they have to notice carefully their health and safety work. They are always guided by a diving manual in their duty, far instance, how to care and use the compressor, pay attention to the wind condition, and the load of diving. The subjects have to provide a time for physical exercise, vitamin supplement and good nutrient as much as they could.

A cooperation should be established among Health Department, Agriculture Department, local government ( Jakarta governor), Naval Hospital Dr. Mintoharjo Jakarta, University of Indonesia ( post graduate program of occupational health and safety) or another relevant institutes in developing a system or organization which take care of fishermen diver's health, chamber of LIBO, research and development of hyperbaric medicine in Indonesia, especially in Jakarta."

"Stuttered speech is a dysfluency rich speech, more prevalent in males than females. It has been associated with insufficient air pressure or poor articulation, even though the root causes are more complex. The primary features include prolonged speech and repetitive speech, while some of its secondary features include, anxiety, fear, and shame. This study used LPC analysis and synthesis algorithms to reconstruct the stuttered speech. The results were evaluated using cepstral distance, Itakura-Saito distance, mean square error, and likelihood ratio. These measures implied perfect speech reconstruction quality. ASR was used for further testing, and the results showed that all the reconstru-cted speech samples were perfectly recognized while only three samples of the original speech were perfectly recognized.Shuttered speech adalah speech yang kaya dysfluency, lebih banyak terjadi pada laki-laki daripada perempuan. Ini terkait dengan tekanan udara yang tidak cukup atau artikulasi yang buruk, meskipun akar penyebabnya lebih kompleks. Fitur utama termasuk speech yang berkepanjangan dan berulang-ulang, sementara beberapa fitur sekunder meliputi, kecemasan, ketakutan, dan rasa malu. Penelitian ini menggunakan LPC analysis dan synthesis algoritma untuk merekonstruksi stuttered speech. Hasil dievaluasi menggunakan jarak cepstral, jarak Itakura-Saito, mean square error, dan rasio likelihood. Langkah-langkah ini terkandung kualitas speech reconstruction yang sempurna. ASR digunakan untuk pengujian lebih lanjut, dan hasilnya menunjukkan bahwa semua sampel speech yang terekonstruksi dikenali dengan sempurna sementara hanya tiga sampel dari speech asli dikenali dengan sempurna."

"Unit Straight Run Motor-Gas Compressor (SRM-GC) merupakan unit kompresor yang mendapatkan tenaga dari sebuah motor yang dikopel secara langsung. Dalam sebuah industri pengolahan, unit SRM-GC memiliki fungsi untuk mengkompresi gas yang didapatkan setelah proses pemisahan antara bahan bakar berbentuk padat, cair, dan gas. Dengan adanya pengkompresian maka gas-gas tersebut dapat dipisahkan berdasarkan fraksi karbonnya.Dalam dunia pemeliharaan (maintenance), reliabilitas dapat diartikan sebagai probabilitas dari suatu item untuk dapat melaksanakan fungsi yang telah ditetapkan selama interval waktu tertentu dalam kondisi pengoperasian yang telah ditetapkan. Jika berbicara tentang reliabilitas maka faktor-faktor lain yang ikut mempengaruhinya tidak dapat dilepaskan, seperti availability, kegagalan (failure), laju kegagalan (failure rate), dan maintainability (M).Reliability Block Diagram (RBD) atau yang sering juga disebut sebagai Dependence Diagram (DD) adalah gambaran grapikal dari hubungan reliabilitas antar komponen dalam suatu sistem untuk menentukan reliabilitas keseluruhan dari sistem tersebut. Dalam RBD dikenal beberapa pola hubungan, tiga diantaranya yang sering digunakan adalah seri (chain of component), paralel (alternative component), dan k-out-of-n. Penelitian pada SRM-GC ini dilakukan untuk mengetahui model reliabilitas dari unit tersebut dengan melakukan pengukuran parameter reliabilitas, pencarian model yang tepat, dan melakukan simulasi Reliability Block Diagram (RBD).

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Unit-Straight Run Gas Compressor Motor (SRM-GC) is a compressor unit which is getting power from a motor that is coupled directly. In a processing industry, SRM-GC unit has a function for compressing gas obtained after the separation of solid fuels, liquid, and gas. By the compression, the gases can be separated based on the fraction of carbon.

In the field of maintenance (maintenance), reliability can be defined as the probability of an item to be able to perform the functions that have been established for a specific time interval in a predetermined operating conditions. If we’re talking about the reliability, we can not ignore the other factors that influence it, such as availability, failure, failure rate and maintainability (M).

Reliability Block Diagram (RBD) or known well as Dependence Diagram (DD) is a grapichal image of the reliability relationship between components in a system to determine the overall reliability of the system. In the RBD, we known some pattern of relationships, three of which are commonly used are the series (chain of component), parallel (alternative component), and k-out-of-n. This SRM-GC study was conducted to determine the reliability models of the unit by measuring the reliability parameters, searching the right model, and simulate Reliability Block Diagram (RBD)."

"ABSTRAKListrik merupakan kebutuhan yang sangat penting dalam kehidupan manusia pada abad ke-21. Salah satu upaya untuk memenuhi kebutuhan energi listrik tersebut adalah teknologi turbin gas. Oleh karena itu, desain impeler dari kompresor merupakan salah satu faktor yang mempengaruhi kinerja dari turbin gas. Metode yang dapat digunakan untuk menganalisis kinerja impeler kompresor adalah metode analisis segitiga kecepatan. Analisis segitiga kecepatan dilakukan dengan perhitungan komponen segitiga kecepatan menggunakan hasil pengukuran FARO Edge dan data aktual pengujian turbin gas GT85-2. Berdasarkan hasil perhitungan, kompresor menghasilkan daya teoritis sebesar 29,2 kW, daya aktual sebesar 24,3 kW, dengan efisiensi 83,15 pada kecepatan putar 90.000 rpm.

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ABSTRACTElectricity is the most important needs for humanity in 21st century. There is one technology to fulfill this need, called gas turbine. One of the factor that influence the performance of gas turbine is compressor impeller design. To analyze the performance of compressor rsquo s impeller, one of the method can be used is velocity triangle analysis. This analysis done by calculation of velocity triangle component that measured using FARO Edge and actual test data for gas turbine GT85 2. Based on the analysis, compressor can afford 29.2 kW theoretical power, 24,3 kW actual power, 83.15 hidrolic efficiency with 90,000 rpm rotational speed."

"In the current study, two experiments are reported that investigated the effects of simple white noise and mixture of white noise and other sounds on perception of speech. In both experiments, university students were recruited to listen to short sentences under various sound masking conditions. Experiment 1, where standard sets of speakers were used for both speech and masking stimuli, has shown that, compared to baseline where there was no masking sound, the participants had significantly greater difficulties in understanding the sentences where the average level of understanding was 28% for the white noise condition and 20% for the mixed noise condition in which white noise was mixed with pink noise and sounds of running water. In Experiment 2, a test model of the specially designed sound masking speaker was used to present the masking noise. Further, sounds of tweeting birds and healing music were added to the mixed noise from Experiment 1 to create the three masking noise conditions. The average level of understanding for the mixed noise condition was 14%, while that for the bird and music conditions were 24% and 30% respectively. The higher understanding rates for the latter conditions were due to lower volume of the mixed white noise in order to keep the overall volume including the birds and music at 55dB. There were also significant effects of sentence type and reading voice gender, suggesting that auditory legibility does not solely depend on the speech-to-noise sound level ratio, but also on other variables, such as, predictability of the sentences, and clarity of the speech. Feedback at the end of the sessions revealed that the participants found mixed noise less irritating than pure white noise, and they preferred mixed noise with bird tweeting or music even better. Thus, it was concluded that mixed noise with occasional sounds of tweeting birds, was the most suitable masking sound for commercial use, being efficient and not unpleasant."