Analisis coal losses pada kegiatan penambangan di Pit Inul Middle Panel 3 PT Kaltim Prima Coal

Coal Losses merupakan proses hilangnya batubara yang terjadi pada saat proses penambangan berlangsung sampai pada saat pengiriman batubara ke tujuan. Proses penambangan batubara seperti clean up roof batubara, proses pemuatan batubara, serta saat pengangkutan batubara menuju stockpile berpotensi menimbulkan coal losses. PT Kalimantan Prima Coal menetapkan coal recovery criteria sebesar 98,5%, lebih ketat dari yang ditetapkan Kementerian Energi dan Sumber Daya Mineral (ESDM) sebesar 90%. Penelitian ini bertujuan untuk menghitung coal losses pada proses clean up batubara, pemuatan batubara di loading point, dan pengangkutan batubara; mengetahui faktor-faktor yang menyebabkan terjadinya coal losses; dan memberi rekomendasi upaya penanganan coal losses.Penelitian dilakukan di Pit Inul Middle Panel 3 pada PT KPC bulan Mei dan Juni 2019. Ada lima seam batubara yang diamati, yaitu seam K17LR, K13, K12, K9 dan K4. PT KPC menggunakan survey yang dibandingkan dengan truck count untuk menghitung coal recovery. Total coal losses yang didapat dari setiap seam dibagi menjadi tiga proses penambangan batubara, yaitu coal losses pada saat clean up roof batubara, di loading point, dan saat hauling.Coal Losses yang didapatkan pada seam K17LR bulan Mei dan Juni 2019 sebesar 4,49% dan 3,93%; seam K13 bulan Mei dan Juni 2019 sebesar 2,83% dan 1,47%; seam K12 bulan Mei dan Juni 2019 sebesar 3,57% dan 2,71%; seam K9 bulan Mei dan Juni 2019 sebesar 4,24% dan 4,15%; seam K4 bulan Mei dan Juni 2019 sebesar 4,3% dan 1,11%. Coal losses yang terjadi masih di atas dari kriteria yang diberikan oleh ESDM sehingga masih memenuhi batas kriteria. Persentase coal losses terbesar terjadi di loading point sehingga dilakukan simulasi pengurangan coal losses di loading point. Total losses 19.43% pada Bulan Mei and dan 13.38% pada Bulan Juni berhasil diturunkan menjadi 9,44% and 6,98%. Kata-kata kunci : batubara, recovery, clean up, loading point, hauling

Prediction Score of Antegrade Chronic Total Occlusion Percutaneous Coronary Intervention Success in Dr. Kariadi Central General Hospital Semarang

Background: Lesion characteristics of chronic total occlusion (CTO) are predictors of percutaneous coronary intervention (PCI) success. A prediction score consist of these predictors can help CTO-PCI operators. Various prediction score had been established but none had been established in Indonesian population. Methods: This observational cohort study was performed in patients underwent native vessel CTO-PCI in Dr.Kariadi Hospital during 2018. Target vessels, ostial lesion, blunt stump, calcification, long lesion, bending, side branch, bridging collateral, and retrograde collateral were angiographic variables proposed to be predictors of CTO-PCI success. All of the variables were quantitatively assessed by two observers. Bivariate and multivariate analysis used to identify independent predictors of CTO-PCI success and to establish a scoring model. Results: A total 200 patients underwent CTO-PCI procedures were included to this study. All of the procedures used antegrade approach. The prediction score established as follows: bending (1 point), calcification (2 point), blunt stump (3 point), long lesion (1 point), and poor retrograde collateral filling (2 point). Total score ranged from 0 to 9 with decreased probability of success from 92.3% to 0.5%. Score value ? 3 categorized as difficult lesion with higher risk to failure compared to score value <3 (OR 15.4; p<0.001). The score model had good calibration and discrimination in predict CTO-PCI success (AUC 0.88; p<0.001). Conclusion: Bending, calcification, blunt stump, long lesion, and poor retrograde collateral were predictors of CTO-PCI success. The score consist of these variables could predict antegrade CTO-PCI success. Keywords: chronic total occlusion; percutaneous coronary intervention; success; prediction score.

A Study on Bio-Diesel and Jet Fuel Blending for the Production of Renewable Aviation Fuel

Aviation industry is considered one of the contributors to atmospheric CO2emissions. It is forced to cut off carbon dioxide emission starting 2020. Current trends in bio-jet production involve mega projects with million dollars of investments. In this study, bio-jet fuel production by blending bio-diesel with traditional jet fuel at different concentrations of bio-diesel (5, 10, 15, 20 vol. %) was investigated. This blending technique will reduce bio-jet production cost compared to other bio-jet techniques. Bio-diesel was originally produced by the transesterification of non-edible vegetable oil (renewable sources), so, its blend with jet fuel will has a reduced carbon foot print. The blend was tested to ensure that the end product will meet the ASTM D1655 international specifications for Jet A-1 and Jet A and can be used in aircrafts.Available data on biodiesel blending with jet fuel in the literature is not consistent, there are many contradictory results. Hence, more investigations are required using locally available feedstocks. The main physicochemical properties for Jet A-1 and Jet A according to ASTM D1655 were tested to check if the blend will be compatible with existing turbojet engine systems. Different tests were conducted; vacuum distillation, smoke point, kinematic viscosity, density, flash point, total acidity and freezing point. In addition, heating value of the blend was calculated. The result was then compared with calculated value using blending indices available in the literature. Blending indices were able to predict the laboratory measured specifications for the studied blends.It was found that only 5% bio-diesel- 95% jet fuel blend (B5) meets ASTM standard for Jet A. Hence, biodiesel can be safely used as a blend with fossil-based jet for a concentration of up to 5% without any change in the ASTM specifications. Freezing point is the most important constrain for this blending technique. Higher blends of biodiesel will cause the bio-jet blend to fail ASTM specifications. In general, blending technique will reduce the cost impact that may have been incurred due to change in infrastructure when using other production techniques.

Neutrophil-Lymphocyte Ratio Superior to Total Leukocyte and Neutrophil in Diagnosing Acute Appendicitis Using Alvarado Score

Background: The diagnosis of acute appendicitis must be performed quickly and accurately to reduce the risk of negative appendectomy without increasing the risk of perforation. Objective: To analyze whether Neutrophil-Lymphocyte Ratio (NL-R) in the modified Alvarado score is more accurate in diagnosing acute appendicitis in comparison with total leukocyte and neutrophil. Method: This was a cross-sectional study and the data were collected from Telogorejo Hospital Semarang (Indonesia) from November 2018 until October 2019. The best cut-off point of NL-R for predicting acute appendicitis was provided through receiver operating characteristic (ROC) curve. NL-R was used to replace total leukocyte and neutrophil to form a modified Alvarado score. Area Under Curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the original Alvarado Score and modified Alvarado score were measured. Results: Sensitivity, specificity, positive predictive value, negative predictive value of the original Alvarado score are 100%, 84.6%, 91.3%, and 100% respectively with cut-off point total score of >4.5. Sensitivity, specificity, positive predictive value, negative predictive value of modified Alvarado score were 100%, 100%, 100%, and 100% respectively with cut-off point total score of >5.5. AUC modified Alvarado Score was 1.000 and AUC original Alvarado Score was 0.985. Conclusion: Modified Alvarado score diagnoses acute appendicitis more accurately than the original Alvarado Score.

ANALISIS PENGENDALIAN PERSEDIAAN BAHAN BAKU DENGAN METODE ECONOMIC ORDER QUANTITY PADA CV. DIKA JOK JENGGAWAH

Tujuan yang diharapkan dari penelitian ini adalah ingin menganalisis persediaan bahan baku optimal yang dibutuhkan dengan menggunakan metode Economic Order Quantity (EOQ), menganalisis berapa besar persediaan pengaman (Safety stock), menganalisis kapan waktu yang tepat untuk melakukan pemesanan kembali (reorder point), menganalisis total persediaan bahan baku atau Total Inventory Cost (TIC). Jenis penelitian yang digunakan adalah kuantitatif deskriptif. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah wawancara, observasi, dan dokumentasi. Penelitian dan hasil perhitungan yang dilakukan menunjukkan bahwa persediaan bahan baku setiap tahunnya tidak stabil. Bahan baku yang dibutuhkan oleh perusahaan apabila dihitung menggunakan metode Economic Order Quantity (EOQ) pada tahun 2016 adalah sebesar 11,52 m3 dengan frekuensi pembelian 6 kali per periode (1 tahun). Tahun 2017 sebesar 9,90 m3 dengan frekuensi pembelian 6 kali per periode (1 tahun). Persediaan pengaman (safety stock) pada tahun 2016 adalah sebesar 16,48 m3. Pada tahun 2017 sebesar 11,25 m3. Titik pemesanan kembali (reorder point) pada tahun 2016 adalah sebesar 17,18 m3. Pada tahun 2017 sebesar 13,1 m3. Total biaya persediaan bahan baku yang dihitung menurut Economic Order Point (EOQ) lebih sedikit dibandingkan dengan yang dikeluarkan oleh perusahaan, maka ada penghematan biaya persediaan. Pada tahun 2016 sebesar Rp.110.499.402 dan pada tahun 2017 sebesar Rp.81.655.306. Kata Kunci: Economic Order Quantity (EOQ), Persediaan Pengaman (Safety Stock), Titik Pemesanan Kembali (Reorder Point), Total Biaya Persediaan atau Total Inventory Cost (TIC).

Kitozán hatóanyagú orrtampon tulajdonságainak vizsgálata állatkísérletes modellen

Introduction: The usefulness of nasal packing after endoscopic sinus surgery is still debated in the literature. Aim: Our aim was to evaluate the effects of a new chitosan-based nasal dressing in animal model. Methods: Standard mucosal damage was caused in both nostrils during endoscope-assisted procedure in ten rabbits. Chitosan nasal packing was inserted in a randomly selected nasal fossa of each animal, while the other side was left unpacked. Symptoms were evaluated during nasal endoscopy on the 12th postoperative week. The degree of mucosal oedema, crusting, adhesions and the nasal discharge were observed according to the modification of the grading system of Berlucchi et al. The higher scores indicated the worse complaints. Results: Assessing the adhesion formation, 1 point was given (mean: 0.1; standard deviation [SD]: 0.32) for the unpacked side, while in the tamponated side no adhesion formation was observed. The total score of crusting in the non-packed side was lower with 1 point (total score: 9, mean: 0.90; SD: 0.74) than in the chitosan side (total score: 10, mean 1.00; SD: 0.82). Discharge or mucosal oedema were not observed during the follow-up period. The mean rate, measured with electronmicroscopy, was 22.06% (SD: 0.25) in the chitosan side, while in the non-packed side it was 36.11% (SD: 0.48). The differences did not show any significance (p = 0.806). Conclusion: During the examinations, none of the animals suffered complications. The symptoms of the packed and the non-packed nasal cavities did not differ significantly on the basis of our examinations. Orv Hetil. 2018; 159(47): 1981–1987.

Breast Self-Examination: Attitudes and Knowledge Among Polish Nurses

Background: Breast cancer (BC) is 1 of the most challenging types of malignant cancer, both in Poland and in the world. Accordingly to the latest epidemiologic data, in Poland in 2015 BC was the most frequent cancer among women and was second leading cause of cancer deaths. World Health Organization highlights that BSE has significant role in empowering women to take responsibility for their own health and is recommended as an educational tool in raising women's awareness about BC risk. Appropriate knowledge level about BSE is especially crucial among nurses - in many cases nurses are the first and only source of knowledge about BSE and BC for women. Aim: To investigate level of knowledge about BSE among Polish nurses. Methods: To assess BSE correctness performed by nurses, authors used the scale based on 4 items. Each item referred to 1 following principle of appropriate BSE: regularity (once a month); BSE performed 2-3 days after menstruation among women in premenopausal age and within the set day among postmenopausal women; using both visual and palpation technique; examination in standing and lying position. For each principle respondent received 1 point. Total maximum number of points was 4. Among the variables characterizing the examined group of nurses potential qualitative and quantitative factors were identified, the impact of which on the correctness of BSE performance has been assessed. To evaluate the impact of specific factors on the probability of correct BSE performance the logistic regression method has been used. Results: In our study all nurses declared that they had performed BSE at least once in their life. However, less than half (41.1%) did this for the first time at the age of 20 or earlier. 56.7% of nurses regularly examined their breasts once a month. Among menstruating women (N = 1058) at the recommended time (2-3 days after the end of menstruation), BSE was performed by 67.3% of nurses, the others during different periods of the menstrual cycle. Among postmenopausal women (N = 184) 30.4% have been performing BSE on a specific day of the month. Almost all subjects (about 98%) used both - viewing and palpation method. 58.9% did it in 2 positions - standing and lying. The average number of points on the BSE correctness scale, including 4 items, was 2.8 points. BSE was fully correctly performed by 27.5% of women (4 p.) and almost fully correctly by 33.9% of nurses (3 p.). Less than 1% of nurses carried out BSE contrary to the 4 recommendations assessed during the study. Conclusion: Despite medical education only about 1/3 of nurses has performed BSE in a completely correct way. It shows the need of constant education in this matter which has significant meaning for same nurses but also for women educated by them. Moreover, in the face of alarming epidemiologic data on BC and unsatisfactory quality of performed BSE, devoting more attention in the nurses´ education process for BC issues should be considered.

P PERBANDINGAN KUALITAS PELUMAS MOTOR 4T DI PALEMBANG DENGAN PARAMETER UJI SPECIFIC GRAVITY, KINEMATIC VISCOSITY, FLASH POINT, POUR POINT, TOTAL ACID NUMBER (TAN) DAN VACUUM DISTILLATION

Pelumas baik yang berasal dari minyak bumi (mineral oil) atau pelumas sintetik umumnya berupa cairan, yang berfungsi untuk mengurangi gesekan diantara dua benda yang bergerak. Pelumas merupakan bagian yang tak terpisahkan dari mesin. Pelumas dibutuhkan mesin untuk melindungi komponen-komponen mesin dari keausan. Proses pembuatan minyak pelumas adalah distilasi atmosfir, distilasi hampa, deasphalting, solvent extraction, dewaxing, blending dan packaging. Untuk mendapatkan pelumas yang baik perlu ditambahkannya aditif yang sesuai dengan kebutuhan. Aditif adalah senyawa kimia yang bila ditambahkan ke dalam pelumas akan menaikkan unjuk kerja pelumas seperti yang diharapkan. Aditif dapat menentukan mutu pelumas yang digunakan karena dapat merubah sifat kimia maupun sifat fisik dari pelumas. Untuk mengetahui kualitas minyak pelumas diperlukan adanya pengujian sifat fisika dan sifat kimia dari pelumas dengan membandingkan hasil uji dari sampel.

Rapid and Simultaneous Prediction of Eight Diesel Quality Parameters through ATR-FTIR Analysis

Quality assessment of diesel fuel is highly necessary for society, but the costs and time spent are very high while using standard methods. Therefore, this study aimed to develop an analytical method capable of simultaneously determining eight diesel quality parameters (density; flash point; total sulfur content; distillation temperatures at 10% (T10), 50% (T50), and 85% (T85) recovery; cetane index; and biodiesel content) through attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and the multivariate regression method, partial least square (PLS). For this purpose, the quality parameters of 409 samples were determined using standard methods, and their spectra were acquired in ranges of 4000–650 cm−1. The use of the multivariate filters, generalized least squares weighting (GLSW) and orthogonal signal correction (OSC), was evaluated to improve the signal-to-noise ratio of the models. Likewise, four variable selection approaches were tested: manual exclusion, forward interval PLS (FiPLS), backward interval PLS (BiPLS), and genetic algorithm (GA). The multivariate filters and variables selection algorithms generated more fitted and accurate PLS models. According to the validation, the FTIR/PLS models presented accuracy comparable to the reference methods and, therefore, the proposed method can be applied in the diesel routine monitoring to significantly reduce costs and analysis time.

Quantification of Training Load During Return to Play After Upper- and Lower-Body Injury in Australian Rules Football

Context:Training volume, intensity, and distribution are important factors during periods of return to play.Purpose:To quantify the effect of injury on training load (TL) before and after return to play (RTP) in professional Australian Rules football.Methods:Perceived training load (RPE-TL) for 44 players was obtained for all indoor and outdoor training sessions, while field-based training was monitored via GPS (total distance, high-speed running, mean speed). When a player sustained a competition time-loss injury, weekly TL was quantified for 3 wk before and after RTP. General linear mixed models, with inference about magnitudes standardized by between-players SDs, were used to quantify effects of lower- and upper-body injury on TL compared with the team.Results:While total RPE-TL was similar to the team 2 wk before RTP, training distribution was different, whereby skills RPE-TL was likely and most likely lower for upper- and lower-body injury, respectively, and most likely replaced with small to very large increases in running and other conditioning load. Weekly total distance and high-speed running were most likely moderately to largely reduced for lower- and upper-body injury until after RTP, at which point total RPE-TL, training distribution, total distance, and high-speed running were similar to the team. Mean speed of field-based training was similar before and after RTP compared with the team.Conclusions:Despite injured athletes’ obtaining comparable TLs to uninjured players, training distribution is different until after RTP, indicating the importance of monitoring all types of training that athletes complete.