scholarly journals PENERAPAN METODE V-SHAPE LOADING UNTUK MENINGKATKAN PRODUKTIVITAS PC-2000 & PC-1250 DI PIT 10 & 11 MADHANI TALATAH NUSANTARA PT. ARUTMIN INDONESIA TAMBANG ASAMASAM

2020 ◽  
Vol 1 (1) ◽  
pp. 69-80
Author(s):  
Enos Enos ◽  
Kurnia Candra Utama ◽  
Rahimatul Fadhilah
Keyword(s):  
Hard Material ◽  
Material Characteristic ◽  
Time Efficiency ◽  
Average Productivity ◽  
Productivity Data ◽  
Loading Method ◽  
Lower Elevation ◽  
Loading Methods

ABSTRAK Data produktivitas fleets overburden removal PT. Madhani Talatah Nusantara Asamasam Coal Project (ACP) Bulan Januari – Mei 2018 masih jauh di bawah target sehingga analisis untuk mengetahui akar permasalahan dan penyelesaiannya perlu dilakukan. Karakteristik material di ACP merupakan material free dig (no blasting & no ripping), namun semakin dalamnya elevasi banyak terdapat area yang merupakan material keras. Pengambilan data awal dengan metode konvensional loading menunjukkan rendahnya produktivitas disebabkan karena lamanya loading time dan spotting time. Lamanya loading time diakibatkan digging rate yang tinggi, sedangkan lamanya spotting time disebabkan karena jauhnya manuver truk untuk memposisikan siap loading. Untuk mempertahankan efisiensi loading time excavator dan mempercepat waktu manuver truk diperlukan perubahan metode loading, yaitu metode V-shape loading.Metode V-shape loading merupakan metode loading dimana posisi truk membentuk sudut “V” terhadap face penggalian. Penerapan metode V-shape loading memerlukan front kerja dengan luas minimal 20 meter untuk PC-2000 dan 15 meter untuk PC-1250. Metode V-shape loading bertujuan untuk mempercepat waktu manuver truk saat memposisikan siap loading, mengurangi swing radius excavator, dan mengurangi waktu angkat bucket excavator sehingga loading time semakin efisien dan produktivitas akan meningkat. Selain itu, metode ini juga mengurangi waktu delay perbaikan front loading oleh alat dorong dozer karena bekas front loading yang tidak dilalui oleh truk.Metode V-shape loading tidak membutuhkan tambahan biaya untuk diterapkan, hanya diperlukan kepedulian pengawas dalam pengaturan di loading point. Sebelum penerapan metode ini, dilakukan sosialisasi untuk mendapatkan pemahaman dari semua pihak yang terlibat, terutama operator dan pengawas lapangan. Setelah itu, barulah dilakukan implementasi di lapangan dengan pengawasan yang ketat. Hasil penerapan dalam 5 bulan pengamatan  menunjukkan adanya efisiensi loading time excavator dan manuver truk sehingga menghasilkan produktivitas yang meningkat. Pada PC-2000, rata-rata produktivitas meningkat 107%, dari sebelumnya 491 bcm/jam menjadi  527 bcm/jam. Sedangkan pada PC-1250, rata-rata produktivitas meningkat 145%, dari sebelumnya 245 bcm/jam menjadi 355 bcm/jam. Kata kunci : produktivitas, V-shape loading  ABSTRACT Productivity data fleets overburden removal at PT. Madhani Talatah Nusantara Asamasam Coal Project (ACP) January – May 2019 was below target, so analysis for knowing the root of the problems and this solution is needed. Material characteristic at ACP is free dig material (no blasting & no ripping), but there are much hard material in case of lower elevation. Conventional loading methods showed low productivity was caused by loading time & spotting time above plan. Longer loading time was caused by longer digging rate, while longer spotting time was caused by longer truck positioning ready to load. For maintaining loading time efficiency & maintaining spotting time, V-shape loading method is applied to change conventional loading method.V-shape loading method is loading method which truck position at “V” angle to loading face. Application V-shape loading method needs large front loading minimal 20 meters for PC-2000 and 15 meters for PC-1250. The purpose of V-shape loading method is for speeding up spotting time for ready to load, reducing bucket excavator lifting time so efficiency loading time & productivity increased. Moreover, this method is reducing delay front loading maintenance by dozer because truck spotting did not get through past loading point.V-shape loading method did not need any cost for applying, just needed concern from foreman for observing at loading point. First, all foreman & operator was given socialization for understanding how to apply this method. Then, V-shape loading applied with tight supervision. The result at 5 month application, there was efficiency loading time excavator & spotting time excavator. For PC-2000, average productivity increased 107%, from 492 bcm/hrs to 533 bcm/hrs. Moreover, for PC-1250, average productivity increased 145% from 245 bcm/hrs to 355 bcm/hrs. Keywords : productivity, V-shape loading 

Hydroxyapatite as a Carrier for Bone Morphogenetic Protein

2011 ◽  
Vol 37 (6) ◽  
pp. 659-672 ◽  
Author(s):  
Ramin Rohanizadeh ◽  
Kimberly Chung
Keyword(s):  
Bone Morphogenetic Proteins ◽  
Therapeutic Effects ◽  
Dicalcium Phosphate Dihydrate ◽  
Immersion Method ◽  
Ideal Candidate ◽  
Loading Method ◽  
Phosphate Dihydrate ◽  
Morphogenetic Protein ◽  
Loading Methods ◽  
Dental Applications

Bone morphogenetic proteins (BMPs) can induce the formation of new bone in numerous orthopedic and dental applications in which loss of bone is the main issue. The combination of BMP with a biomaterial that can carry and deliver proteins has been demonstrated to maximize the therapeutic effects of BMPs. However, no ideal candidate with optimal characteristics as a carrier has emerged for clinical use of BMPs. Hydroxyapatite (HA) is a potential BMP carrier with its osteoconductive properties and desirable characteristics as a bone graft biomaterial. In this study, 3 different methods to load BMP into HA materials were characterized and compared based on the BMP uptake and release profile. BMP was loaded into HA in 3 ways: (1) incorporation of BMP during HA precipitation, (2) HA immersion in BMP solution, and (3) BMP incorporation during dicalcium phosphate dihydrate (DCPD) conversion to HA. The size of HA crystals decreased when BMP was loaded during HA precipitation and HA immersion in BMP solution; however, it did not change when BMP was loaded during DCPD-to-HA conversion. The highest BMP uptake was achieved using the immersion method followed by HA precipitation, and the lowest via DCPD conversion. It is interesting to note that BMP loading during HA precipitation resulted in sustained and prolonged BMP release compared with the 2 other BMP loading methods. In conclusion, BMP incorporation during HA precipitation revealed itself to be the best loading method.

scholarly journals Produktivitas Cengkih Hutan (Syzygium obtusifolium L.) di Kecamatan Leihitu Kabupaten Maluku Tengah

2019 ◽  
Vol 15 (1) ◽  
pp. 31-37
Author(s):  
Herman Rehatta ◽  
Dessy A Marasabessy ◽  
Safril H Sopalauw
Keyword(s):  
Significant Role ◽  
Research Method ◽  
Survey Method ◽  
State Revenue ◽  
Average Productivity ◽  
Yield Level ◽  
Productivity Data ◽  
Old Trees

Clove trees (Syzygium obtusifolium L.) have a significant role in supporting efforts to increase state revenue. The purpose of this study was to obtain a productivity data of the forest clove in the Leihitu Sub-district, Central Maluku District, from a case study in Hitu Lama, Hitu Mesing, Mamala, and Morela villages. The research method used was a survey method.  The results showed that variations in the yield level in each study location were influenced by the factor of the proportion of immature trees, productive trees, and damaged old trees.  The average productivity of forest clove in the study location was 5603.5 kg/ha or equivalent to 5.6 tons/ha.   Keywords: forest clove, production, productivity, tree conditions   ABSTRAK Tanaman cengkih (Syzygium obtusifolium L.) mempunyai peranan yang cukup besar dalam menunjang upaya peningkatan pendapatan negara. Tujuan penelitian ini adalah untuk mendapatkan data produktivitas cengkih hutan di kecamatan Leihitu Kabupaten Maluku Tengah, dari studi kasus di desa-desa Hitu Lama, Hitu Mesing, Mamala, dan Morela. Metode penelitian menggunakan metode survey. Hasil penelitian menunjukkan adanya variasi tingkat produksi pada masing-masing lokasi penelitian, dipengaruhi oleh faktor proporsi tanaman belum menghasilkan, tanaman menghasilkan, dan tanaman tua rusak. Menunjukkan rata-rata produktivitas cengkih hutan di lokasi penelitian adalah 5603,5 kg/ha atau setara dengan 5,6 ton/ha. Kata Kunci: cengkih hutan, produksi, produktivitas, kondisi tanaman

scholarly journals Assessment of Photocatalytic Hydrogen Production from Biomass or Wastewaters Depending on the Metal Co-Catalyst and Its Deposition Method on TiO2

Catalysts ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 584 ◽  
Author(s):  
Mikel Imizcoz ◽  
Alberto V. Puga
Keyword(s):  
Hydrogen Production ◽  
Noble Metals ◽  
Treatment Method ◽  
H2 Production ◽  
Catalyst Loading ◽  
Co Catalyst ◽  
Photocatalytic Hydrogen Production ◽  
Loading Method ◽  
Pre Treatment ◽  
Loading Methods

A systematic study on the solar photocatalytic hydrogen production (photoreforming) performance of M/TiO2 (M = Au, Ag, Cu or Pt) using glucose as a model substrate, and further extended to lignocellulose hydrolysates and wastewaters, is herein presented. Three metal (M) co-catalyst loading methods were tested. Variation of the type of metal results in significantly dissimilar H2 production rates, albeit the loading method exerts an even greater effect in most cases. Deposition-precipitation (followed by hydrogenation) or photodeposition provided better results than classical impregnation (followed by calcination). Interestingly, copper as a co-catalyst performed satisfactorily as compared to Au, and slightly below Pt, thus representing a realistic inexpensive alternative to noble metals. Hydrolysates of either α-cellulose or rice husks, obtained under mild conditions (short thermal cycles at 160 °C), were rich in saccharides and thus suitable as feedstocks. Nonetheless, the presence of inhibiting byproducts hindered H2 production. A novel photocatalytic UV pre-treatment method was successful to initially remove the most recalcitrant portion of these minor products along with H2 production (17 µmol gcat−1 h−1 on Cu/TiO2). After a short UV step, simulated sunlight photoreforming was orders of magnitude more efficient than without the pre-treatment. Hydrogen production was also directly tested on two different wastewater streams, that is, a municipal influent and samples from operations in a fruit juice producing plant, with remarkable results obtained for the latter (up to 115 µmol gcat−1 h−1 using Au/TiO2).

Welder learning curves behaviour: “focus on welding productivity with the TIG process of marine platforms stainless steel pipes”

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Bruno Sobral Macedo ◽  
Miguel Luiz Ribeiro Ferreira
Keyword(s):  
Stainless Steel ◽  
Learning Curves ◽  
Superior Performance ◽  
Content Type ◽  
Average Productivity ◽  
Productivity Data ◽  
Asme Code ◽  
The Impact ◽  
Welding Productivity

PurposeThe purpose of the study is to analyse the feasibility of using the potential and exponential curve models to assess the learning of a group of welders, when welding stainless steel piping with the tungsten inert gas process.Design/methodology/approachThe welding productivity data grouped according to the requirements of the ASME SECTION IX code is organised into two groups: average productivity and baseline productivity. When processing the adjustment to the two models, the Excel software Solver tool was used. The criteria for assessing the quality of the fit were: least squared method, Spearman's correlation coefficient and graphical method. The impact of the variation coefficient on the average productivity and the amplitude (difference between the minimum and maximum productivity) was also evaluated on the baseline productivity.FindingsThe curves elaborated based on the average productivity presented better quality of adjustment than those constructed from the baseline productivity. The potential and exponential models presented similar adjustment conditions, with the second having a slightly superior performance. There were no productivity gains due to learning in the studied time interval. The grouping of the average daily productivity data based on the diameter range established in the ASME code section IX presented satisfactory results, enabling its use by the industry.Originality/valueThere is no news of work on piping welding with this focus. The proposal to group the productivity data according to the degree of difficulty of execution established by the ASME code section IX, widely used in the industry, is a significant contribution to monitoring the evolution of learning. In the same way, the results allow to adopt the average productivity determined from the first 20 days of realisation of a project, as a reasonable indicator to estimate the future performance of the work, helping to correct deadlines during the realisation of a project.

Research on Different Loading Methods of the Multi-Roller-Pressing Flexible Stretch Forming

2014 ◽  
Vol 898 ◽  
pp. 257-260
Author(s):  
Wei Chuan Zhang ◽  
Yong Feng Li ◽  
Ming Zhe Li
Keyword(s):  
Vibration Amplitude ◽  
Sheet Material ◽  
Stretch Forming ◽  
Forming Force ◽  
Forming Process ◽  
Explicit Finite Element ◽  
Force Loading ◽  
Loading Method ◽  
Loading Methods ◽  
Distribution Of Stress

Based on the multi-roller-pressing flexible stretch forming (MRPFSF) process, force loading and displacement loading were researched. The process of spherical parts of 08AL sheet material were simulated by means of an explicit finite element method. The variations of the forming force in stretch-forming process and the distribution of stress after springback were analyzed comparatively for both loading methods. The results show that the change of the forming force in the force loading method has fluctuation. With the depressing of rollers, the vibration amplitude is smaller. At the end of forming, the forming forces of both loading methods are gradually consistent. The stress distribution of spherical parts formed by the two loading method is accordant.

scholarly journals Assessment of the Mixing of Polydisperse Solid Particles in the Rotary Drum and Slant Cone Mixers Using Discrete Element Method

2021 ◽  
Author(s):  
Basel Alchikh-Sulaiman
Keyword(s):  
Discrete Element Method ◽  
Discrete Element ◽  
Direct Result ◽  
Disperse Particles ◽  
Loading Method ◽  
Mixing Quality ◽  
Rotary Drum ◽  
Loading Methods ◽  
The Impact ◽  
Element Method

In spite of wide applications of powders in industry, there is a lack of sufficient knowledge regarding the mixing of poly-disperse particles in rotary drum and slant cone mixers. The main objective of this study was to explore the mixing quality of mono-disperse, bi-disperse, tri-disperse, and poly-disperse particles inside rotary drum and slant cone mixers as a function of the drum speed, particle size, agitator speed, and the initial loading method through the discrete element method (DEM). To achieve this objective, experimental work and simulations were carried out. DEM results were validated using experimental data obtained from both sampling and image analysis techniques. DEM simulation results were in good agreement with the experimentally determined data, both qualitatively and quantitatively. Three major loading methods were defined: side-side, top-bottom, and back-front. Also, the mixing metric was utilized to measure the mixing quality. For bi-disperse particles inside the slant cone mixer, the mixing index increased to a maximum and decreased slightly before reaching a plateau at the drum speed of 15 rpm with different loading methods as a direct result of the segregation of particles of different sizes. The same behavior was observed in the rotary drum for bi-disperse, tri-disperse, and poly-disperse particles. The effect of agitator speed on the mixing performance for bi-disperse particles inside the slant cone mixer was also investigated. The addition of the agitator increased the mixing quality and reduced the segregation of particles with different sizes. The best mixing qualities for the tri-disperse and poly-disperse particles inside the rotary drum were recorded for the top-bottom smaller-to-larger loading method. For the slant cone mixer, highest mixing indices for tri-disperse and poly-disperse particles with the top-bottom smaller-to-larger loading method were obtained at drum speeds of 15 and 55 rpm, respectively. The impact of segregation for both mixers was reduced by introducing additional intermediate size particles.

scholarly journals Assessment of the Mixing of Polydisperse Solid Particles in the Rotary Drum and Slant Cone Mixers Using Discrete Element Method

2021 ◽  
Author(s):  
Basel Alchikh-Sulaiman
Keyword(s):  
Discrete Element Method ◽  
Discrete Element ◽  
Direct Result ◽  
Disperse Particles ◽  
Loading Method ◽  
Mixing Quality ◽  
Rotary Drum ◽  
Loading Methods ◽  
The Impact ◽  
Element Method

In spite of wide applications of powders in industry, there is a lack of sufficient knowledge regarding the mixing of poly-disperse particles in rotary drum and slant cone mixers. The main objective of this study was to explore the mixing quality of mono-disperse, bi-disperse, tri-disperse, and poly-disperse particles inside rotary drum and slant cone mixers as a function of the drum speed, particle size, agitator speed, and the initial loading method through the discrete element method (DEM). To achieve this objective, experimental work and simulations were carried out. DEM results were validated using experimental data obtained from both sampling and image analysis techniques. DEM simulation results were in good agreement with the experimentally determined data, both qualitatively and quantitatively. Three major loading methods were defined: side-side, top-bottom, and back-front. Also, the mixing metric was utilized to measure the mixing quality. For bi-disperse particles inside the slant cone mixer, the mixing index increased to a maximum and decreased slightly before reaching a plateau at the drum speed of 15 rpm with different loading methods as a direct result of the segregation of particles of different sizes. The same behavior was observed in the rotary drum for bi-disperse, tri-disperse, and poly-disperse particles. The effect of agitator speed on the mixing performance for bi-disperse particles inside the slant cone mixer was also investigated. The addition of the agitator increased the mixing quality and reduced the segregation of particles with different sizes. The best mixing qualities for the tri-disperse and poly-disperse particles inside the rotary drum were recorded for the top-bottom smaller-to-larger loading method. For the slant cone mixer, highest mixing indices for tri-disperse and poly-disperse particles with the top-bottom smaller-to-larger loading method were obtained at drum speeds of 15 and 55 rpm, respectively. The impact of segregation for both mixers was reduced by introducing additional intermediate size particles.

Effect of Drug Loading Method on Drug Dissolution Mechanism of Amoxicillin Trihydrate Encapsulated in Chitosan-Poly(N-Vinylpyrrolidone) Full-IPN Hydrogel as a Floating Drug Delivery System Matrix

2019 ◽  
Vol 964 ◽  
pp. 251-256
Author(s):  
Ahmad Ichsan Baihaqi ◽  
Dyah Utami Cahyaning Rahayu ◽  
E. Budianto
Keyword(s):  
Drug Loading ◽  
Drug Dissolution ◽  
Dissolution Mechanism ◽  
Dissolution Test ◽  
Cross Sectional ◽  
First Order ◽  
Loading Method ◽  
Amoxicillin Trihydrate ◽  
Loading Methods

Amoxicillin trihydrate suits to be encapsulated into a modified matrix to increase its bioavailability. In this study, the effect of drug loading methods on drug dissolution mechanism from chitosan-poly(N-vinylpyrrolidone) hydrogel with CaCO3 as the effervescent agent has been studied. It was found that the encapsulation efficiency of in situ and post loading methods were 93% and 75%, respectively. The dissolution values were 94% and 98%, respectively for in situ and post loading. The dissolution test data was incorporated into zero-order, first-order, Higuchi and Korsmeyer-Peppas models to evaluate the kinetic and the mechanism of the drug dissolutions. The in situ loading method fits well to first-order model (R2 = 0.9772), while the post loading method fits well to Higuchi model (R2 = 0.9880). Based on Korsmeyer-Peppas model, the dissolution mechanism of in situ loading was Fickian diffusion (n = 0.4024), while post loading was a combination of diffusion and erosion (n = 0.5532). From the SEM images, it showed that the surface and cross-sectional of the post loading method hydrogel formed pores and pore channels, both before and after the dissolution test. Meanwhile, on the surface and the cross-sectional of in situ loading method hydrogel had pores and pore channels only after dissolution test.

A Novel Cell-Loading Method into Porous β-TCP Blocks

2006 ◽  
Vol 309-311 ◽  
pp. 993-996
Author(s):  
Ichiro Torigoe ◽  
Shinichi Sotome ◽  
A. Tsuchiya ◽  
Kenichi Shinomiya
Keyword(s):  
Bone Formation ◽  
The Novel ◽  
Cell Loading ◽  
Pressure Method ◽  
Loading Method ◽  
Loading Efficiency ◽  
Novel Method ◽  
Loading Methods ◽  
In Vivo Bone Formation

In the field of bone tissue engineering using cells combined with scaffolds, it is important to efficiently load cells into porous scaffolds. We devised a novel cell-loading method into porous beta-tricalcium phosphate (β-TCP) blocks. In this study, we compared this method with two conventional cell-loading methods in terms of cell-loading efficiency and in vivo bone formation capability. Bone marrow stromal cells (BMSCs) were obtained from the femurs of Fisher rats. After about 10 days of culture, BMSCs were harvested and suspended in the plasma of the Fisher rats at a concentration of 2×106 cells/ml. This cell suspension was loaded into porous β-TCP cubes (5×5×5mm) by using three loading methods: a soaking method, a post low-pressure method and a pre low-pressure method (the novel method). These β-TCP cubes were cross-sectioned and stained with toluidine blue and cell-counted. Cell-loading efficiency was significantly higher when using the novel methods. For the study of in vivo bone formation capability, nearly confluent BMSCs were exposed in an osteogenic medium supplemented with 10-7 M dexamethasone, 50µg/ml L-ascorbic acid phosphate and 10mM β-glycerophosphate for 4 days. These osteogenic cells were harvested and suspended in the plasma of the Fisher rats at a concentration of 2×106 cells/ml. This cell suspension was loaded into porous β-TCP cubes (5×5×5mm) by using the three cell-loading methods. Immediately, these β-TCP cubes were implanted at subcutaneous sites in the backs of 7-week-old male Fisher rats and harvested at postoperative 3 and 6 weeks. After cross-sectioning, these sections were stained with hematoxylin and eosin, and the new bone formation area was quantified. Consistent with cell-loading efficiency, in vivo bone formation capability was significantly higher in the novel method at postoperative 6 weeks. We showed the usefulness of the novel cell-loading method in bone tissue engineering.

Accuracy of Four Language Analysis Procedures Performed Automatically

2001 ◽  
Vol 10 (2) ◽  
pp. 180-188 ◽  
Author(s):  
Steven H. Long ◽  
Ron W. Channell
Keyword(s):  
Automatic Identification ◽  
Published Data ◽  
Typically Developing ◽  
Language Impaired ◽  
Productivity Data ◽  
Language Analysis ◽  
Word Classes ◽  
Human Coder ◽  
Impaired Children ◽  
Metalinguistic Skills

Most software for language analysis has relied on an interaction between the metalinguistic skills of a human coder and the calculating ability of the machine to produce reliable results. However, probabilistic parsing algorithms are now capable of highly accurate and completely automatic identification of grammatical word classes. The program Computerized Profiling combines a probabilistic parser with modules customized to produce four clinical grammatical analyses: MLU, LARSP, IPSyn, and DSS. The accuracy of these analyses was assessed on 69 language samples from typically developing, speech-impaired, and language-impaired children, 2 years 6 months to 7 years 10 months. Values obtained with human coding and by the software alone were compared. Results for all four analyses produced automatically were comparable to published data on the manual interrater reliability of these procedures. Clinical decisions based on cutoff scores and productivity data were little affected by the use of automatic rather than human-generated analyses. These findings bode well for future clinical and research use of automatic language analysis software.

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