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"A series of cyclic triaxial tests at very low frequency was carried out on unsaturated clean sand in order to quantitatively investigate the influence of the degree of saturation on dynamic response. The conventional triaxial testing apparatus, which is usually used on saturated soil, was employed to test the unsaturated soil with the additional pore air pressure controller. During the series of tests, four different degrees of saturation level (Sr = 55%, 70%, 85%, 98%) were applied to the soil specimen based on a single value of effective confining pressure (?’3). The results revealed that the application of cyclic loading at a very low frequency occurring continuously triggered the decrease of soil resistance. For degree saturation, Sr = 55% revealed that the resistance of soil was stronger in comparison to another level. Furthermore, the experimental results confirmed that applied cyclic loading induced a change in saturation level before and after testing. In addition, at a certain level of saturation, a phenomenon of settlements was likely to occur and the soil specimen then underwent liquefaction."

"In this research, based on actual data gathered from an industrial scale vacuum gas oil (VGO) hydrocracker and artificial neural network (ANN) method, a model is proposed to simulate yields of products including light gases, liquefied petroleum gas (LPG), light naphtha, heavy naphtha, kerosene, diesel and unconverted oil (off-test). The input layer of the ANN model consists of the catalyst, feed and recycle flow rates, and bed temperatures, while the output neurons are yields of those products. The results showed that the AAD% (average absolute deviation) of the developed ANN model for training, testing, and validating data are 0.445%, 1.131% and 0.755%, respectively. Then, by considering all operational constraints, the results confirmed that the decision variables (i.e., recycle rate and bed temperatures) generated by the optimization approach can enhance the gross profit of the hydrocracking process to more than $0.81 million annually, which is significant for the economy of the target refinery."

"Penelitian ini telah berhasil melakukan pengujian produksi gas klor menggunakan membran penukar kation dan membran nafion dengan metode elektrolisis plasma. Pengujian ini meliputi pengukuran pH, konduktivitas, produksi gas klor dan konsumsi energi selama proses reaksi berlangsung. Hasil pengujian menunjukkan penggunaan membran penukar kation meningkatkan kemurnian produk NaOH. Produksi gas klor pada membran penukar kation meningkat 4,3 kali dibandingkan dengan membran nafion dan meningkat 1,3 kali dibandingkan dengan tanpa menggunakan membran. Sementara konsumsi energi per mmol produk menurun 3,1 kali dibandingkan dengan membran nafion dan menurun 1,7 kali dibandingkan dengan tanpa menggunakan membran. Hasil pengujian elektrolisis plasma dengan membran penukar kation menunjukkan terjadi peningkatan produksi gas klor sebesar 33,3 kali dibanding proses elektrolisis dengan membran penukar kation. Sementara konsumsi energi per mmol produk menunjukkan penurunan dari 473,64 kJ/mmol pada proses elektrolisis menjadi 25,85 kJ/mmol pada proses elektrolisis plasma.

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This study has successfully tested the production of chlorine gas using a cation-exchange membrane and nafion membrane with plasma electrolysis method. These tests include measurement of pH, conductivity, chlorine gas production and energy consumption during the reaction. The test results showed the use of cation exchange membrane increases NaOH product purity. The production of chlorine gas on the cation exchange membrane increased 4.3 times compared with the nafion membrane and increased 1.3 times compared with no use of membrane. While energy consumption per mmol product decreased 3.1 times compared with the nafion membrane and decreased 1.7 times compared with no use of membranes. The test results of plasma electrolysis with cation exchange membrane showed an increase in the production of chlorine gas by 33.3 times compared with the electrolysis process cation exchange membrane. While energy consumption per mmol of the product showed a decline of 473.64 kJ / mmol in the electrolysis process be 25.85 kJ / mmol on plasma electrolysis process."

"ABSTRAKSegmen 2 Kota Bogor dan Segmen 3 Kabupaten Bogor DAS Ciliwung bagiantengah mengalami perubahan penggunaan lahan yang cukup pesat selama duadekade terakhir. Tujuan penelitian adalah menganalisis trend penggunaan lahanpada 1989-2012, dampaknya terhadap penurunan stok karbon/peningkatan emisiCO2eq, dan penyebab utamanya, memproyeksikan Reference Level (RL) padatahun 2020, dan menyusun strategi pembangunan rendah emisi karbon di keduasegmen. Metode yang digunakan yaitu survey lokasi pada tiap tipe penggunaanlahan yang diolah menggunakan Sistem Informasi Geografis (SIG), telaahdokumen sosial ekonomi dan kebijakan, dan forecasting RL. Hasilnya diharapkandapat memberikan berbagai arahan kegiatan mitigasi emisi karbon dalam strategipembangunan rendah emisi karbon pada kedua segmen. Perubahan penggunaanlahan pada 1989-2012 memperlihatkan bahwa terjadi penurunan luasan ruangterbuka hijau (RTH) hingga 2.575,57 ha sedangkan non-RTH meningkat hingga2.575,57 ha. Hal ini berdampak pada menurunnya stok karbon hingga 26.900ton.C dan melepaskan emisi CO2eq hingga 98.723 ton.CO2eq. Penyebabperubahan penggunaan lahan yaitu pertambahan penduduk, kebutuhan lahan, danketerbatasan lahan. Proyeksi RL hingga tahun 2020 dilakukan berdasarkankondisi standar (BAU) dan rencana ke depan (FL). Hasil proyeksimemperlihatkan bahwa FL adalah skenario terbaik yang diestimasi menyimpankarbon hingga 217.610 ton.C di tahun 2020. Strategi pembangunan rendah emisikarbon diarahkan pada penambahan luasan RTH hingga 20% melalui arahankegiatan mitigasi emisi karbon pada penggunaan lahan RTH dan non-RTHmeliputi kegiatan perlindungan, pemantauan, penyuluhan, dan penegakan hukum.

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ABSTRACTSecond Segment Bogor City and Third Segment Bogor Regency of Ciliwungmiddlestream watershed land use has changed drastically over the past twodecades. This study was conducted to analyze land use trend in 1989-2012, itsimpact on decreasing carbon stock/increasing CO2eq emission, to projectReference Level (RL) to 2020, and establishment of Low Carbon EmissionDevelopment Strategy in both segments. The methods were survey on each type ofland use which would be processed using Geographical Information System(GIS), literature study of socio-economic and policy documents, and forecastingRL. The results were expected to provide guidance for carbon emission mitigationactivities in low carbon emission strategies in both segments. Land use changes in1989-2012 indicated a reduction of green space area by 2.575,57 ha whereasnon-green space area increases by 2.575,57 ha. These changes resulted indecreasing carbon stock by 26.900 ton.C and releasing CO2eq emission by98.723ton.CO2eq. Population growth, demand for lands, and land constraintswere found to be the driving factors of land use changes in these area. ReferenceLevel to 2020 was established based on business as usual (BAU) and forwardlooking (FL). The projection shows that FL was the best scenario which estimatedcarbon storage by 217.610 ton.C in 2020. Low carbon development strategydirected at the area of green space adding up to 20% through the guidance forcarbon emission mitigation activities based on green space and non-green spacewhich covered from protection, supervision, extention/awareness rising, and lawenforcement activities."

"This text is an introduction to the physics of collisional plasmas, as opposed to plasmas in space. It is intended for graduate students in physics and engineering . The first chapter introduces with progressively increasing detail, the fundamental concepts of plasma physic. The motion of individual charged particles in various configurations of electric and magnetic fields is detailed in the second chapter while the third chapter considers the collective motion of the plasma particles described according to a hydrodynamic model. The fourth chapter is most original in that it introduces a general approach to energy balance, valid for all types of discharges comprising direct current(DC) and high frequency (HF) discharges, including an applied static magnetic field. The basic concepts required in this fourth chapter have been progressively introduced in the previous chapters. The text is enriched with approx. 100 figures, and alphabetical index and 45 fully resolved problems. Mathematical and physical appendices provide complementary information or allow to go deeper in a given subject."

"ABSTRAKStudi teoritis struktur dan spektrum elektronik kompleks lantanida terpyridinetersubstitusi gugus heterosiklik tak jenuh cincin 5 yaitu pyrrole, furan danthiophene telah dilakukan menggunakan metode Sparkle/RM1 untuk memperolehgeometri yang mendekati keadaan yang sebenarnya. Analisis energi, muatanparsial dan panjang ikatan dilakukan untuk memperoleh sifat strukturnya. Untukmendapatkan spektrum elektronik, sparkle diganti dengan titik muatan denganposisi ligan hasil optimasi geometri Sparkle/RM1, dengan menggunakan metodeZINDO/S. Hasil optimasi geometri menunjukkan bahwa metode Sparkle/RM1dapat digunakan untuk memprediksi geometri ligan dan kompleks lantanidaterpyridine tersubstitusi gugus heterosiklik tak jenuh. Hasil optimasi menunjukkanbahwa ion lantanida pada kompleks [Ln(L)(NO3)3] memiliki bilangan koordinasi9, yang berikatan dengan satu ligan tridentat L (terpyridine tersubstitusi gugusheterosiklik) dan tiga gugus nitrat sebagai ligan bidentat Perhitungan frekuensiligan dan kompleks lantanida terpyridine tersubstitusi gugus heterosiklik tak jenuhmenghasilkan spektrum IR dengan cukup akurat. Analisis spektrum elektronikmenghasilkan spektrum UV-Vis kompleks [Ln(L)(NO3)3] memiliki serapan yanglebih tinggi dan memiliki serapan yang lebih besar dari spektrum UV-Vis ligandalam keadaan bebas.

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ABSTRACTTheoretical studies of structure and electronic spectra on lantanides complexes ofunsaturated five-membered heterocyclic rings substituted terpyridine has beenconducted using the Sparkle/RM1 method. The structures optimized usingSparkle/RM1 method to obtain the most close structures with those in realexperiments. Energy, partial charge and bond distance analysis have been done topredict the structure properties. For the calculation of the electronic spectra of thecomplexes, the sparkle is replaced by a point charge with ligand held in thepositions as determined by Sparkle/RM1, and uses a ZINDO/S methods. Theresult of the calculation showed that free ligand and its lanthanides complexescould be predicted by Sparkle/RM1 methods. Optimized geometri showed that inthe complex [Ln(L)(NO3)3], lanthanide ion is 9-coordinate, being bonded to onetridentate L ligand (unsaturated heterocyclic substituted terpyridine) and threebidentate nitrates. IR spectra from the frequency calculation of the ligand and itscomplexes has been obtained with a good acuracy. The calculation of theelectronic/UV-Vis spectra of the complexe [Ln(L)(NO3)3] has more higherabsorption and displaying a red shift than UV-Vis spectra of free ligand."

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Pertumbuhan perusahaan penyedia jasa ride-hailing adalah sebuah fenomena yang sudah cukup umum terjadi, khususnya di negara-negara berkembang. Permintaan yang terus meningkat sejalan dengan pertumbuhan populasi membuat perusahaan dan layanannya ini disebut sebagai salah satu inovasi yang paling berdampak selama satu dekade terakhir. Selain mampu memfasilitasi kebutuhan mobilisasi dari masyarakat di daerah perkotaan, khususnya Jabodetabek, keberadaan dari perusahaan penyedia layanan ride-hailing juga berhasil mendorong kenaikan yang signifikan pada perekonomian digital Indonesia. Namun, meskipun demikian, permasalahan emisi gas rumah kaca yang timbul dari operasionalnya tidak bisa dihindari seiring dengan pertumbuhan perusahaan tersebut. Melihat potensi pencemaran udara yang akan semakin parah seiring berjalannya waktu, pemerintah harus mengambil langkah tegas untuk bisa mengatasi hal ini. Kebijakan untuk mendorong kesadaran masyarakat dalam menggunakan transportasi publik dan menetapkan target penggunaan kendaraan listrik sebagai operasional layanan ride-hailing adalah beberapa hal yang harus pemerintah pertimbangkan dalam mengatasi permasalahan yang akan datang nantinya. Pemodelan kondisi nyata dengan metode sistem dinamis digunakan untuk menguji signifikansi dari faktor-faktor yang akan diajukan sebagai fokus pemerintah dalam membuat kebijakan. Dengan begitu, alternatif yang sudah teruji faktornya bisa dijadikan sebagai rekomendasi untuk membuat kebijakan terkait perusahaan penyedia layanan ride-hailing.

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The growth of ride-hailing service providers is a fairly common phenomenon, especially in developing countries. Increasing demand in line with population growth has made this company and its services nominated as one of the most impactful innovations of the past decade. Apart from being able to facilitate the mobilization needs of people in urban areas, especially Jabodetabek, the presence of ride-hailing service providers has also succeeded in driving a significant increase in Indonesia's digital economy. However, even so, the problem of greenhouse gas emissions arising from its operations cannot be avoided along with the company's growth. Seeing the potential for air pollution to get worse over time, the government must take firm steps to overcome this. Policies to encourage public awareness in using public transportation and setting targets for the use of electric vehicles as ride-hailing service operations are some of the things the government must consider in overcoming future problems. Real conditions modeling with the system dynamic method is used to test the significance of the factors that will be proposed as the government's focus in making policies. Therefore, alternatives that have been factor-tested can be used as recommendations for making policies regarding ride-hailing service provider companies."

"Carola Vogel’s PhD thesis focuses on the synthesis, and structural and spectroscopic characterization of the first high valent iron nitride complexes. In her interdisciplinary and collaborative research Carola also describes the reactivity studies of a unique iron (V) nitride complex with water. These studies show that quantitative yields of ammonia are given at ambient conditions. High valent iron nitride and oxo species have been proposed as key intermediates in many bio-catalytic transformations, but until now these species have proven exceedingly challenging to isolate and study. Iron complexes in high oxidation states can thus serve as models for iron-containing enzymes to help us understand biological systems or aid our development of more efficient industrial catalysts."

"Emisi gas buang kendaraan bermotor khususnya yang berbahan bakar bensin berpotensi meningkatkan kandungan CO di perparkiran bawah tanah dua kali lebih besar dalam empat bulan. Korelasi konsentrasi CO, HC dan Opasitas dari emisi gas buang dengan perparkiran sangat erat dengan nilai r untuk rata-rata kandungan CO mencapai 0.9845. Kandungan CO dan HC dapat terakumulasi di perparkiran tertutup dengan terbatasnya ventilasi, sirkulasi udara dan exhaust. Perancangan sistem perparkiran yang memadai dan memenuhi kaidah Kesehatan dan Keselamatan Kerja menentukan seberapa besar akumulasi CO.Kandungan CO dalam darah dan Phenol dalam air kemih merupakan indikasi paparan CO emisi gas buang kendaraan dengan udara ruang parlor P2 BEJ. Kandungan CO berdampak negatif langsung terhadap kesehatan manusia. CO dengan cepat dapat menggeser 02 dari dalam darah karena CO dengan Hb membentuk COHb dengan cepat 200 - 300 kali lebih kuat dari oksigen dalam mengikat Hb darah. Dampak CO terhadap pekerja parkir tergantung lamanya pemajanan dan konsentrasi CO nya. Perokok lebih berisiko terhadap pajanan CO di P2. Kondisi pekerja yang terpajan CO di P2 sudah relatif terganggu, potensi hipoksia sudah megganggu sistem kardiovaskuler terlihat dari keluhan-keluhan pekerja seperti nyeri kepala, pusing, mual dan vertigo.Pengendalian dampak emisi gas buang dapat dilakukan oleh pekerja secara proaktif. Tindakan preventif dengan menekan emisi gas buang melalui penyuluhan pemeliharaan mesin secara teratur, pemiiihan jenis dan tahun produksi kendaraan. Pengelola gedung sebaiknya melakukan tindakan perbaikan yang terpadu mencakup perencanaan system perparkiran, ventilasi, sirkulasi udara dan sistem pengaturan kerja.

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Within four month periods the gas emissions from burning gasoline vehicles has the potential to doubling increase of the carbon monoxide (CO) concentration in the underground parking area. The correlation of HC, CO and Opacity of gas emission is very close to the parking indoor air quality, it shows by the r-value of CO about 0.9845. CO and HC content can be accumulated in the indoor parking area due to the poor ventilation, air circulation, number and capacity of exhaust fans. The adequate parking system designs that meet with Health and Safety requirement will effect the CO content accumulation.

The CO content in the blood and phenol in the urine are indicating the employee exposure to CO vehicles gas emission and P2 BET parking indoor air quality. The CO concentration at P2 has direct impact to the parking employee health. Carbon monoxide quickly reduce the oxygen intake from blood stream and by binding carbon monoxide with hemoglobin (Hb) to become a carboxyhemoglobin (COHb) compounds that toxic to human. CO bound Hb rapidly 200 - 300 times stronger than oxygen in the blood. The effect of carbon monoxide to the employee depends on the duration of exposure and CO concentration. Moreover smokers have a higher risk to the CO exposure in the P2. The condition of employee who expose to the CO at P2 has relatively been affected of the gas emission and will suffering from hypoxia with aggravated cardiovascular problem such as head pain, headache, fatigue and vertigo.

The employee can proactively participate in controlling of vehicles gas emission. Preventive action by minimizes the gas emission through awareness program, regular engine maintenance, choosing type of vehicles and year of product are parts of better control_ The building management should concern a continuous improvement through corrective action such as redesign the parking system, ticketing system, ventilation system, and shift work system of the employee."