bluuebunny/crossref_metadata_2025 huggingface dataset:
Production Tubing Leak Repair Using Reinforced Thermoplastic Pipe
Authors: Oloruntobi Olalere Sunday , Chandran Prasanna Kumar , Abu Bakar M Azuan , Zulkarnain Nurul Nazmin , A Rahman Hasrizal , Das Debasis Priyadarshan , Tiwari Pankaj Kumar , Yahaya Azahari
Published: March 2021

Operators are faced with never-ending well integrity issues relating to tubing leaks. This situation is particularly important in oil and gas wells that are producing in corrosive environments. When a well can no longer be safely produced due to well integrity issues relating to tubing leaks, an expensive workover is often performed to restore the tubing integrity. To improve the economics of a well intervention involving tubing leak repairs, a new cost-effective method is being proposed. The novel technology involves the installation of reinforced thermoplastic pipe (RTP) inside the existing tubing to isolate multiple leaks using a coiled tubing unit or an E-line. The RTP is engineered for downhole applications with custom designed connectors and accessories. It is designed to handle corrosive fluids (CO2 and H2S) and prevent downhole erosion caused by sand production. The RTP can be used to eliminate tubing – annulus communication in both producers and injectors with full compliance to well integrity management system. The results of the field trial in a gas injector well in Malaysia basin show that the RTP can provide a reliable means of restoring and enhancing the production of oil and gas with considerable cost savings (up to 80% cost reduction when compared to a conventional workover). In most cases, the high cost associated with a conventional workover can make it uneconomical when compared to the expected hydrocarbon recovery from the well, resulting in production deferment (well shut-in). The RTP can significantly increase the viability of repairing a larger percentage of the wells that are shut-in due to the loss of tubing integrity when the hydrocarbon recovery from the well is insufficient to justify a full workover. The significant cost savings provided by the RTP would dramatically improve economics and would likely result in more reserves recovered. The RTP also has a smoother surface that contributes to minimum friction and reduces the risk of scales formation when compared to the steel tubing of the same internal diameter.
Design and Execution of the First Large-Scale Polymer Injection Pilot in Sirikit Oil Field
Authors: Wuttipittayamongkol Weeraya , Trinavarat Pannapon , Nuntaprayoon Warisa , Pancharoen Monrawee , Laochamroonvorapongse Rapheephan
Published: March 2021

Becoming more mature with field-wide water flooding implementation for more than 30 years, Sirikit Oil Field (S1) is going forward to the next rejuvenating step of enhanced oil recovery (EOR). Generally, the field contains light oil (40° API) in highly stratified sand-shale sequences with low net-to-gross ratios. High reservoir temperature, low permeability, and high water cut observed from production make it even more challenging for polymer injection projects. Nonetheless, the success from a small-scale field trial has shown a promising future of EOR application in the field and brought an execution of the first large-scale polymer injection pilot.

Polymer screening laboratory tests, a reservoir simulation study, data acquisition program and techniques, injectivity tests, polymer injection unit design, and risk assessment were parts of the pilot preparation, in which the key learnings from the previous pilot have been incorporated. The gathering and determination of baseline parameters including production performance, injection profiles, reservoir fluid saturation profiles, etc., were registered for ultimate evaluation. Then, the continuous polymer injection has been started since October 2019 in two separated fault blocks where 12 injectors and 20 producers are located in different injection patterns.

During several months of polymer injection, both foreseen and unforeseen changes have enlivened the pilot management. Although the injectivity test with polymer solution prior to the pilot demonstrated no injection difficulty, several wells have shown injectivity deterioration with time. Mechanical degradation is induced in these wells by the installation of flow restriction devices to lessen solution viscosity and, hence, prolong polymer injectivity. Well integrity issues and artificial lift breakdown negatively affect field production and close-in wells make it harder for voidage replacement control. Immediate troubleshooting and close monitoring have been placed and eventually leads to the recognition of encouraging results. Polymer helps improve vertical injection profiles as seen from injection logging. Saturation logging presents a sign of oil saturation decrease around the wellbore area. Reduction of water cut and rise of oil production have pleasantly come after a few months from the start. Intensive surveillance program will be continued over the course of pilot injection.

The critical success of the EOR pilot execution depends on the detailed planning, prudent surveillance and comprehensive evaluation. Sirikit oil field is moving to a turning point and the pilot outcome would lead the way to a further milestone, so as to avoid premature end of the field's production.
An Integrated Reservoir Predicting Approach with Geological Constraints from Stratigraphic Forward Modeling of the Miocene Fan Delta in Albert Basin, Uganda
Authors: Xu Wei , Fang Lei , Zou Jingyun , Guo Fuxin , Zhang Yingchun , Chen Kaiyuan
Published: March 2021

Reservoir prediction is a core area of research in oilfield exploration and development, and it is generally constructed on a combination of well data, seismic attributes or inversion. However, reservoir prediction in sparse well areas poses great challenges due to insufficient well control. If the quality of seismic data is poor, the spatial distribution characteristics of reservoirs cannot be effectively characterized through inversion or attribute analysis, which seriously affects the prediction accuracy. This paper proposes a new method to solve the difficulty in reservoir prediction of oilfields with sparse data and poor quality seismic cube, which evolves from depositional models, forward stratigraphic modeling (FSM) to geocellular modeling. First, based on the comprehensive analysis of core, seismic, grain size, heavy minerals, dip data, it is believed that a special fan delta developed in the Miocene strata in the south of Albert Basin. The reservoirs are dominated by distributary channels, which are in medium-coarse grains, and the provenance is from the southwest to flowing to the northeast. The formation thickness of the stratum decreases from the boundary fault to the direction of the basin. Then, the input parameters of FSM modeling are quantitatively expressed based on the sedimentary model research, including model boundary conditions, basic input information, sediment supply and transportation. FSM results were used to quantitatively characterize the deposition process. The FSM simulation results are compared with the depositional model and well data to verify the reliability. Finally, the shale content model in FSM results is resampled to the geocellular grids and used as the constraint for facies model and property model in geological modeling. This model is used for well pattern design and optimization. This new approach integrates the conceptual depositional model with quantitative FSM results. It improves the accuracy of reservoir prediction and provides a new technical workflow for reservoir characterization. Furthermore, it helps to obtain more insight into the sedimentary process and reduces the risk of oilfield exploration and development.
Modeling Condensate Banking Mitigation by Enhanced Gas Recovery Methods
Authors: Mohsin Adel , Abd Abdul Salam , Abushaikha Ahmad
Published: March 2021

Condensate banking in natural gas reservoirs can hinder the productivity of production wells dramatically due to the multiphase flow behaviour around the wellbore. This phenomenon takes place when the reservoir pressure drops below the dew point pressure. In this work, we model this occurrence and investigate how the injection of CO2 can enhance the well productivity using novel discretization and linearization schemes such as mimetic finite difference and operator-based linearization from an in-house built compositional reservoir simulator. The injection of CO2 as an enhanced recovery technique is chosen to assess its value as a potential remedy to reduce carbon emissions associated with natural gas production. First, we model a base case with a single producer where we show the deposition of condensate banking around the well and the decline of pressure and production with time. In another case, we inject CO2 into the reservoir as an enhanced gas recovery mechanism. In both cases, we use fully tensor permeability and unstructured tetrahedral grids using mimetic finite difference (MFD) method. The results of the simulation show that the gas and condensate production rates drop after a certain production plateau, specifically the drop in the condensate rate by up to 46%. The introduction of a CO2 injector yields a positive impact on the productivity and pressure decline of the well, delaying the plateau by up to 1.5 years. It also improves the productivity index by above 35% on both the gas and condensate performance, thus reducing production rate loss on both gas and condensate by over 8% and the pressure, while in terms of pressure and drawdown, an improvement of 2.9 to 19.6% is observed per year.
Gas Migration Mechanisms and Their Effects on Caprock Seal Capacity: A Case Study in Depleted Gas Fields in the Sarawak Basin, Offshore Malaysia
Authors: Widyanita Ana , Cai Zhong , Mat M Noor , Ali Siti Syareena , Hamid Mohd Khaidhir , Jones Ernest A
Published: March 2021

This paper focuses on the gas characteristics in caprock interval and the gas migration mechanisms from the carbonate reservoir into the caprock and its effects on caprock seal capacity. The workflow mainly includes three methods:(1) Gas geochemistry analysis from the GWD (Gas While Drilling) data to understand the gas composition, their distribution and mechanism for gas migration; (2) Petrophysical analysis to understand the rock types, petrophysical properties and the pore-throat system; and (3) Pore pressure prediction to understand the pressure sealing capacity of the caprock. Integrating the results from these three aspects, the sealing capacity can be evaluated by capillary pressure sealing, pore pressure sealing and the effects on the sealing efficiency for CO2.

There are two gas migration mechanisms in the area: gas diffusion and gas advection. The gas in the caprock of Field A shows decreasing molecular weight trend from deep to shallow depths implying migration from the underlying carbonate reservoir by gas diffusion. However, the gas in the caprock of Field B where there is a gas chimney visible in the seismic data, has composition similar to the gas in carbonate reservoir, suggesting that the gas came from carbonate reservoir below by gas advection through faults and induced fractures and occurred simultaneously with the gas accumulation in the reservoir. There is also gas in the caprock above the gas chimney with lighter molecular weight representing gas that migrated from the gas chimney by gas diffusion.

The caprock seal capability in the two fields are different. The gas in the carbonate reservoir in Field A can be sealed and trapped by the high displacement/entry pressure of the capillary pore-throat system and the abnormally high pore pressure in the caprock. The gas chimney at Field B would be connected to the carbonate reservoir below over geological time and there is effective seal enough to contain hundreds ft of gas column in the carbonate reservoir.

The understanding of the leaking mechanism in these two fields is helpful for understanding the leakage scale, the effects on the sealing capacity, the risk evaluation and mitigation amendment.
Design and Implementation of a Water-Based Micronized Weighting Agent Fluid System for Deepwater Drill Stem Testing Operation in Environmentally Restricted Location
Authors: Motta Marcelo Dourado , Loureiro Sebastião de Andrade
Published: March 2021

The use of micronized weighting agents, in multiple operations, have become more commonplace over the years, with current applications now going far beyond their targeted original purpose of reducing pressure losses in extended reach wells. This specific case reports the development of a fit for purpose system engineered to tackle multiple challenges such as: limitation in using heavy density brines composed of bromides in an offshore environment; hydrate suppression under Drill Stem Test (DST) conditions; weighting agent sagging control; plugging of downhole tools due to heavy solids loading; proper pressure transmission for downhole tools activation; and formation damage prevention.

The operation involved the following steps: 1 - development of a Water-based Micronized Weighting Agent Fluid System (WBMWAFS), laboratory testing, simulation evaluation and testing validation for all target properties; 2 - development of an appropriate DST approach with the usage of a designed set of explosives to minimize formation damage and the interaction of the DST fluid with such cargos; and 3 - the evaluation of the overall system performance in order to validate the integrated approach used to design such solution.

The DST results indicated that the WBMWAFS is capable of delivering all the technical requirements for a trouble-free operation, with no significant register of weighting agent sag, hydrates or with any variation in fluid properties, whilst enabling a DST operation that demonstrated a negative skin damage during the clean-up period and no damage associated with the WBMWAFS. The WBMWAFS performance opens the possibility of the application of this type of fluid as a replacement for high-density clear brines in many challenging environments.
One Trip 7" Multi Zone Gravel Pack System: Success Case and Learning Points from the First Installation in Malaysia
Authors: Nordin M. Helmi , Jamal Ajmal Faliq , Hairi M. Helmie , Magna Bela Sunanda
Published: March 2021

Main reservoirs in this brown field are designed with Cased Hole Gravel Pack (CHGP), which is a proven sand control technique in the area. Most multi-stack reservoirs in these wells require individual sand control treatment on each zone as the formation properties varies from one to another. One of the most recent success case was the installation of One Trip 7" Multi Zone System that enabled implementation of an optimized High Rate Water Pack sand control operation in the casing size. This new technique helps to make more multi zone CHGP in infill or sidetracked wells feasible and more economical.

Previously, CHGP design in 7" casing was limited to stack pack design which means the steps of sump packer installation, perforation, deburr run, GP assembly installation and GP pumping have to be repeated for every zone. The repeated process was laborious and incurred a lot of cost due to the extensive rig time. With the new 7" one-trip design that evolved from the existing 9-5/8" system, the multiple zone GP treatment can be done in single trip and contributes to significantly reduced well cost. One of the design consideration that need to be focused on is selection of carrier fluid to ensure optimum carrying capability during proppant placement while reducing the pumping friction through the one trip system.

Full coverage of screens and blanks was achieved for both zones that were completed with the One Trip 7" Multi Zone completion. Both zones were treated with hybrid pack that is combination of circulating and HRWP. The primary objectives on optimizing rig time were achieved in eliminating multiple runs for different zones, as well as reducing risks of multiple disengagement with lower assembly that adds difficulty during reverse-out operation.

One of the key limitations of this system is the high friction pressure when pumping through long concentric wash pipes and this can affect the effectiveness during proppant reverse out, especially considering the burst rating of the casing as well. Due to this known restriction, cement have been designed and tested up to the anticipated annular pressure during reversing out operation. Another design factor that could also pose a challenge during operation is the limit of sand concentration that is 1 ppa and this again is due to concentric wash pipe design.
Effectiveness of Dynamic Response Spectroscopy and Microwave Inspection Technology for Substrate Pipe and Composite Wraps
Authors: Ahmed Rehan , Mohd Ramli Siti Haslina , A. Aziz Fadhlan B. , Arifin Rosman
Published: March 2021

This paper discusses in depth the technical differentiations of the Direct Response Spectroscopy (DRS) and Microwave (MW) system along with its capabilities of inspecting through various hard to inspect coatings and wraps, making the DRS and MW combo an ideal inspection technique. As with every technology, the limitations of the DRS and MW systems will also be covered to give an unbiased view in the technology selection. This paper will also course through the successful trial at one of PETRONAS operating onshore plants with the detailed result presentation concluding with the efficiency and cost effectiveness of employing the DRS and MW for inspection of composite wraps.

The DRS and MW systems, both proprietary technologies developed by Sonomatic, are used in combination to assess the integrity of pipes and pipelines under composite overwrap repairs. These Non-Destructive Testing technique. are robust, reliable and possess the ability to inspect composite overwrap repairs and the piping substrate while online.

The DRS is essentially an ultrasonic corrosion mapping technique that Measures steel WT with ±0.5 mm accuracy and identifies flaws in composite materials. It is engineered to excite the steel with low ultrasonic frequencies where conventional high frequency ultrasound could not penetrate. The MW measures depth of flaws in the wrapping materials identified by DRS inspection. It operates on very low power and is excellent on the inspection of non-conductive material.
Mechanism and Prevention Method of Producing Hydrogen Sulfide in High Temperature Hydraulic Fracturing Well
Authors: Yuan Zebo , Wang Xiaoqiang , Zhou Lizhi , Liu Huifeng , Li Xu , Jin Yu
Published: March 2021

For a successful hydraulic fracturing operation, shear recovery and thermal stability are critical in terms of successful fracture creation and proppant placement. Sodium thiosulfate is one of the most commonly used gel stabilizers in fracturing gel. This paper reported a well in sulfur-free gas reservoir produced hydrogen sulfide as much as 20000ppm after hydraulic fracturing operation.

A series of experiments were carried out to reveal the mechanism of hydrogen sulfide production. Results showed that in solution with PH less than 6.5, when the temperature is higher than 119 degrees Celsius, sodium thiosulfate will react with hydrogen ions to generate hydrogen sulfide. In this complex reaction, there is also precipitation of elemental sulfur, which may block the pores of the reservoir and thence counteract the effect of hydraulic fracturing. The acidic solution in a fractured well is from (1) Spent acid left downhole due to pre-acid used to reduce fracturing pressure, and (2) Sulfuric acid produced by the decomposition of ammonium persulfate which is used as gel breaker at high temperature.

This paper proposed two solutions to the problem of high-temperature fracturing fluids,one is to use a sulfur-free temperature stabilizer,and the other is to create a non-acid downhole environment. The opinions provided by this paper can help the operators reduce the risk of the damage of hydrogen sulfide and protect the integrity of the well of high temperature fracturing wells.
Pushing 30 Years Multiple Brown Fields Limits Through Artificial Lift and Facilities Improvement
Authors: Ariffin Mohd Hafizi , M Khalil Muhammad Idraki , M Razali Abdullah , Mostaffa M Iman
Published: March 2021

Most of the oil fields in Sarawak has already producing more than 30 years. When the fields are this old, the team is most certainly facing a lot of problems with aging equipment and facilities. Furthermore, the initial stage of platform installation was not designed to accommodate a large space for an artificial lift system. Most of these fields were designed with gas lift compressors, but because of the space limitation, the platforms can only accommodate a limited gas lift compressor capacity due to space constraints. Furthermore, in recent years, some of the fields just started with their secondary recovery i.e. water, gas injection where the fluid gradient became heavier due to GOR drop or water cut increases. With these limitations and issues, the team needs to be creative in order to prolong the fields’ life with various artificial lift.

In order to push the limits, the team begins to improve gas lift distribution among gas lifted wells in the field. This is the cheapest option. Network model recommends the best distribution for each gas lifted wells.

Gas lifted wells performance highly dependent on fluid weight, compressor pressure, and reservoir pressure. The change of these parameters will impact the production of these wells. Rigorous and prudent data acquisitions are important to predict performance. Some fields are equipped with pressure downhole gauges, wellhead pressure transmitters, and compressor pressure transmitters. The data collected is continuous and good enough to be used for analysis.

Instead of depending on compressor capacity, a high-pressure gas well is a good option for gas lift supply. The issues are to find gas well with enough pressure and sustainability. Usually, this was done by sacrificing several barrels of oil to extract the gas.

Electrical Submersible Pump (ESP) is a more expensive option compared to a gas lift method. The reason is most of these fields are not designed to accommodate ESP electricity and space requirements. Some equipment needs to be improved before ESP installation. Because of this, the team were considering new technology such as Thru Tubing Electrical Submersible Pump (TTESP) for a cheaper option.

With the study and implementation as per above, the fields able to prolong its production until the end of Production Sharing Contract (PSC). This proactive approach has maintained the fields’ production with

The paper seeks to present on the challenges, root cause analysis and the lessons learned from the subsequent improvement activities. The lessons learned will be applicable to oil fields with similar situations to further improve the fields’ production.
Useful Parameters in Dynamic Contrast-enhanced Ultrasonography for Identifying Early Response to Chemotherapy in a Rat Liver Tumor Model
Authors: Taiji Ryosuke , Nishiofuku Hideyuki , Tanaka Toshihiro , Minamiguchi Kiyoyuki , Fukuoka Yasushi , Saito Natsuhiko , Taguchi Hidehiko , Matsumoto Takeshi , Marugami Nagaaki , Hirai Toshiko , Kichikawa Kimihiko
Published: March 2021

Objectives:

The objective of the study is to determine a parameter on the time-intensity curve (TIC) of dynamic contrast-enhanced ultrasonography (DCE-US) that best correlates with tumor growth and to evaluate whether the parameter could correlate with the early response to irinotecan in a rat liver tumor model.

Material and Methods:

Twenty rats with tumors were evaluated (control: Saline, n = 6; treatment: Irinotecan, n = 14) regarding four parameters from TIC: Peak intensity (PI), k value, slope (PI × k), and time to peak (TTP). Relative changes in maximum tumor diameter between day 0 and 10, and parameters in the first 3 days were evaluated. The Mann-Whitney U-test was used to compare differences in tumor size and other parameters. Pearson’s correlation coefficients (r) between tumor size and parameters in the control group were calculated. In the treatment group, relative changes of parameters in the first 3 days were compared between responder and non-responder (<20% and ≥20% increase in size on day 10, respectively).

Results:

PI, k value, PI × k, and TTP significantly correlated with tumor growth (r = 0.513, 0.911, 0.665, and 0.741, respectively). The mean RC in k value among responders (n = 6) was significantly lower than non-responders (n = 8) (mean k value, 4.96 vs. 72.5; P = 0.003).

Conclusion:

Parameters of DCE-US could be a useful parameter for identifying early response to irinotecan.
Effect of Dental Thermoplastic Materials on the Clinical Effectiveness of Clear Aligner
Authors:   School of Dentistry, Kiel University, Germany, L Hallmann , MD Gerngro ,   Institute of Material Science, Faculty of Engineering, Kiel University, Germany
Published: March 2021

Objective: The aim of this review is to evaluate the influence of chemical and mechanical material properties properties on the effectiveness of the clinical treatment with a clear aligner. Methods: A systematic literature study of recent and most relevant publications in this field has been performed to identify the most important material effects on the clinical effectiveness of clear aligners. Results: Clear aligner devices have found a wide application in orthodontics. The development of new materials which are metal-free and the CAD/CAM engineering technique make it possible to treat the various kinds of malocclusion. Patients prefer clear aligners because of their aesthetics and comfort. The thermoplastic materials have inherent advantages: excellent aesthetic appearance, simple to be used and superior formability. Various thermoplastic materials are being developed for manufacturing of clear aligners. The mechanical properties of polymers play a crucial role in the effectiveness of the therapeutic treatments. Therefore, the elasticity, dimension and environment stability as well as biocompatibility are the main conditions, which the polymer must meet for being used in clear aligners. Conclusions: The main advantages of clear aligner in comparison to metal or ceramic devices is their excellence aesthetic with better patient acceptance and a general better quality of life. From a clinical point of view, the treatment with clear aligner causes less pain compared to a traditional treatment and also reduce the damage to the gingiva and perodontal tissue. The clinical success of the clear aligner therapy strongly depends on the properties of the used aligner materials. Significance: The use of thermoplastic materials for orthodontic tooth movements requires a better understanding of the material properties for selecting the optimal material and design.
Editorial note
Authors: Editors QIC
Published: March 2021

quantum information, statistics, probability
Toward implementation of coding for quantum sources and channels
Authors: Sasaki M.
Published: March 2021

We review our experiment on quantum source and channel codings, the most fundamental operations in quantum info-communications. For both codings, entangling letter states is essential. Our model is based on the polarization-location coding, and a quasi-single photon linear optics implementation to entangle the polarization and location degrees of freedom. Using single-photon events in a subset of possible cases, we simulate quantum coding-decoding operations for nonorthogonal states under the quasi-pure state condition. In the quantum channel coding, we double the spatial bandwidth (number of optical paths), and demonstrate the information more than double can be transmitted. In the quantum source coding, we halve the spatial bandwidth to compress the data and decompress the original data with the high fidelity approaching the theoretical limit.
On the quantumness of a Hilbert space
Authors: Fuchs C.A.
Published: March 2021

We derive an exact expression for the quantumness of a Hilbert space (defined in C.A. Fuchs and M. Sasaki, Quant. Info. Comp. {\bf 3}, 377 (2003)), and show that in composite Hilbert spaces the signal states must contain at least some entangled states in order to achieve such a sensitivity. Furthermore, we establish that the accessible fidelity for symmetric informationally complete signal ensembles is equal to the quantumness. Though spelling the most trouble for an eavesdropper because of this, it turns out that the accessible fidelity is nevertheless easy for her to achieve in this case: Any measurement consisting of rank-one POVM elements is an optimal measurement, and the simple procedure of reproducing the projector associated with the measurement outcome is an optimal output strategy.
Quantum circuits for incompletely specified two-qubit operators
Authors: Shende V.V. , Markov I.L.
Published: March 2021

While the question ``how many CNOT gates are needed to simulate an arbitrary two-qubit operator'' has been conclusively answered -- three are necessary and sufficient -- previous work on this topic assumes that one wants to simulate a given unitary operator up to global phase. However, in many practical cases additional degrees of freedom are allowed. For example, if the computation is to be followed by a given projective measurement, many dissimilar operators achieve the same output distributions on all input states. Alternatively, if it is known that the input state is $\ket{0}$, the action of the given operator on all orthogonal states is immaterial. In such cases, we say that the unitary operator is incompletely specified; in this work, we take up the practical challenge of satisfying a given specification with the smallest possible circuit. In particular, we identify cases in which such operators can be implemented using fewer quantum gates than are required for generic completely specified operators.
An information theoretical model for quantum secret sharing schemes
Authors: Imai H. , Mueller-Quade J. , Nascimento A.C.A. , Tuyls P. , Winter A.
Published: March 2021

Similarly to earlier models for quantum error correcting codes, we introduce a quantum information theoretical model for quantum secret sharing schemes. This model provides new insights into the theory of quantum secret sharing. By using our model, among other results, we give a shorter proof of Gottesman's theorem that the size of the shares in a quantum secret sharing scheme must be as large as the secret itself. Also, we introduced approximate quantum secret sharing schemes and showed robustness of quantum secret sharing schemes by extending Gottesman's theorem to the approximate case.
New construction of mutually unbiased bases in square dimensions
Authors: Wocjan P. , Beth T.
Published: March 2021

We show that k=w+2 mutually unbiased bases can be constructed in any square dimension d=s^2 provided that there are w mutually orthogonal Latin squares of order s. The construction combines the design-theoretic objects (s,k)-nets (which can be constructed from w mutually orthogonal Latin squares of order s and vice versa) and generalized Hadamard matrices of size s. Using known lower bounds on the asymptotic growth of the number of mutually orthogonal Latin squares (based on number theoretic sieving techniques), we obtain that the number of mutually unbiased bases in dimensions d=s^2 is greater than s^{1/14.8} for all s but finitely many exceptions. Furthermore, our construction gives more mutually unbiased bases in many non-prime-power dimensions than the construction that reduces the problem to prime power dimensions.
Quantum computing and polynomial equations over Z_2
Authors: Dawson C.M. , Haselgrove H.L. , Hines A.P. , Mortimer D. , Nielsen M.A. , Osborne T.J.
Published: March 2021

What is the computational power of a quantum computer? We show that determining the output of a quantum computation is equivalent to counting the number of solutions to an easily computed set of polynomials defined over the finite field Z_2. This connection allows simple proofs to be given for two known relationships between quantum and classical complexity classes, namely BQP/P/\#P and BQP/PP.
Can quantum cryptography imply quantum mechanics? -- reply to Smolin
Authors: Halvorson H. , Bub J.
Published: March 2021

Clifton, Bub, and Halvorson (CBH) have argued that quantum mechanics can be derived from three cryptographic, or broadly information-theoretic, axioms. But Smolin disagrees, and he has given a toy theory that he claims is a counterexample. Here we show that Smolin's toy theory violates an independence condition for spacelike separated systems that was assumed in the CBH argument. We then argue that any acceptable physical theory should satisfy this independence condition.
Webcorner updates
Authors: Kok P.
Published: March 2021

conferences, meetings, schools
Reducing hERG Toxicity Using hERG Classification Model and Fragment-growing Network
Authors: Yang Yan , Zhang Yanmin , Chen Xingye , Hua Yi , Xing Guomeng , Deng Chenglong , Liang Li , Lu Tao , Chen Yadong , Liu Haichun
Published: March 2021

Drug-induced cardiotoxicity has become one of the major reasons leading to drug withdrawal in past decades, which is closely related to the blockade of human Ether-a-go-go-related gene (hERG) potassium channel. Developing reliable hERG predicting model and optimizing model can greatly reduce the risk faced in drug discovery. In this study, we constructed eight hERG classification models, the best of which shows desirable generalization ability on low-similarity clinical compounds, as well as advantages in perceiving activity gap caused by small structural changes. Furthermore, we developed a hERG optimizer based on fragment grow strategy and explored its usage in four cases. After reinforcement learning, our model successfully suggests same or similar compounds as chemists’ optimization. Results suggest that our model can provide reasonable optimizing direction to reduce hERG toxicity when hERG risk is corresponding to lipophilicity, basicity, the number of rotatable bonds and pi-pi interactions. Overall, we demonstrate our model as a promising tool for medicinal chemists in hERG optimization attempts.
Anti-diabetic activity of Erythrina subumbrans (Hassk.) Merr.
Authors: Ganesh S  , Vijey Aanandhi M
Published: March 2021

α-amylase inhibitors present in pancreatic region has an operative strategy by controlling the breakdown of starch and helps to minimize the post-prandial hyperglycemia levels. In this study, vegetative (leaf) part of herbal plant Erythrina subumbrans (Hassk.) was assessed for anti-diabetic activity. Aqueous ethanol (80 %) extract was prepared in the different concentration (10, 20, 40, 80, 160, and 320 µg/ml). Acarbose was used as a standard and treated in similar way as that of sample. Control samples were also prepared without standard and sample solutions. A known volume of α-amylase solution was added (0.1mg/mL) was added to standard, sample, control solutions which were preincubated at 37 °C for 15 minutes. Further, known volume of starch solution was added and incubated for 60 min to initiate the reaction. Hydrochloric acid (HCl) and iodine reagent was added to the test tubes and absorbance was measured at 580 nm in UV-Vis spectrophotometer. A strong pancreatic amylase inhibitory activity (>50 %) was obtained from aqueous ethanolic extract with IC50 (half maximal inhibitory concentration) value of 23 µg/ml against standard acarbose with IC50 value of 27 µg/ml. The values endorse Erythrina subumbrans (Hassk.) for further experiments on their potential for managing Diabetes.
Efficacy of Ashwagandha (withania somnifera [l.] Dunal) in improving cardiorespiratory endurance (VO2 max test) in healthy subjects
Authors: Bargale Sushant Sukumar  , Tripathy T B  , Shashirekha H K  , Suhas Kumar Shetty
Published: March 2021

In Ayurveda, certain herbal formulas are considered to be Rasayana and they are typically taken over periods of time to regenerate both brain and body tissue. Ashwagandha (Withania Somnifera) is used as an adaptogen, antioxidant, immune modulator, free radical scavenger, anti stress, anti arthritic, antispasmodic, anti inflammatory, nervous tonic, nerve soothing and anticancer agent. Ashwagandha (WS) as a nutritional supplement is yet too established. Maximum oxygen uptake (VO2 max) is a gold standard of cardiopulmonary and muscle cell fitness is considered.  The study evaluated the efficacy of Ashwagandha to improve cardiorespiratory endurance (VO2 max) in healthy subjects. They randomized single blind controlled comparative clinical study. 54 health volunteers in each group, study group received Ashwagandha Choorna 12gm with milk (200ml) empty stomach in the morning and the control group only milk (200ml). Maximal capacity of oxygen intake in ml/kg/min (VO2 max) with Rockport fitness walking test of both study and control group were measured before intervention (0th day), after the intervention (60th day) and follow up (90th day). A significant improvement in the VO2 max (F=20.675, P <0.0001) and Hemoglobin (X2=74.150 P <0.0001) in the study group was found. Supplementation of Ashwagandha (Withania Somnifera) with milk improve hemoglobin and VO2 max (maximum aerobic capacity).
BUDAYA KONTEMPLASI SUATU KUNCI KEBAHAGIAAN HIDUP (WELL BEING): Dalam Perspektif Psikologi Islami
Authors: Sutarjo Sutarjo
Published: March 2021

Contemplation becomes a necessity for individuals who want his happiness. Happiness is here not only means happiness lahiriyah alone, but also about the inner happiness that is hard to measure empirically.In this paper the word contemplation more mentioned the term "evaluation" or muhasabah, because the term is more often heard. This paper discusses how an individual effort that happy life (well-being) in this modern era in Islamic psychology perspective.In contemplation of the psychological perspective of Islamic culture can be beneficial for the individual to be more careful of his life. To gain peace of mind, it takes a kind of guidebook in life. So with no manual human steps to be sure, and no way home. This paper describes what a Muslim is supposed to make a guide book in his life in order to achieve well-being
KONSEP PENDIDIKAN ISLAM MASA RASULULLAH DAN SAHABA
Authors: Rahman Abdul
Published: March 2021

Education is something that is essential for human life. Because of the importance of education, Islamic education puts a high position. This can be seen in the Qur'an and Hadith that explains a lot about education. This paper describes the intricacies of the concept of education at the time of the Prophet and his best friend. Prophet as uswatun hasanah for Muslims, of course, has a lot of incised gold ink on education. Similarly, the friends that are the best ummah after the Prophet, had left the pillars of Islamic education that is worth for us to learn and apply in life. As the next generation of the Islamic caliphate, Muslims today should always explore the relics of the education system and the time of the Prophet Sahat. In this way, the Islamic education in the present and future will remain victorious.
GURU: DIGUGU DAN DITIRU
Authors: Ghofar Abdul
Published: March 2021

The paper intitled: â€œTeachers: Obeyed and Imatated â€œ describes how criteria and requirement for any requirements that must be possessed by the teacherÂ  so thatÂ  he becomes a teacher who is heard his advice and obeyed all his orders, as well as his behavior could be an example for his student . He is a professional teacher.To be a professional teacher then he shoud seek as optimal as possible to meet the competencies that must be owned by a teacher. The competencies include professional competence,Â  pedagogical competent, social competence and personal competence as well he should be healthy physically and spiritually. Profesional teachers are teachers who are able to manage themselves in carrying out their duties daily.Criteria professional teachers include : 1) having tellent as a teacher, 2) having skill as ateacher, 3) having a good as expertise and integrated, 4) having a healthy mental, 5) able-bodied, 6) having extensive experience and knowledge, 7)having spirit of Pancasila, 8) the teacher is a good citizen.There are four programs that can be developed in the framework of the establishment of professional teachers, namely 1) pre-service education; 2) in-service education; 3) in-service training; andÂ  4) on-service training.
MENIMBANG KUALITAS PENDIDIKAN ISLAM DAN KOMPETENSI MANAJERIAL KEPALA SEKOLA
Authors: Solihah Een
Published: March 2021

The quality of educational institutions will not be separated from the quality and managerial competence of the leadership of the institution. The more competent and professional managerial, a principal will bring an effect on the quality of the institution he leads. Because of the importance of the principal's quality and managerial competence, it is regulated in several government regulations. As a manager, the principal must have at least four strategies, namely Plan, do, check, act. In addition, the principal must always be oriented towards quality, so the institution he leads still exists.
PENGARUH DIVERSIFIKASI OPERASIONAL DAN PROFITABILITAS TERHADAP STRUKTUR MODAL PADA PERUSAHAAN BUMN SEKTOR PERBANKAN YANG TERDAFTAR DI BURSA EFEK INDONESIA
Authors: Wairooy Mohamad Ali
Published: March 2021

This study aims to examine and analyze the effect of operational diversification and profitability on capital structure in state-owned banking companies listed on the Indonesia stock exchange. Data collection uses secondary data by using purposive sampling technique. The population in this study were all state-owned banking sector companies listed on the Indonesia stock exchange during the period 2008-2016 a total of 41 companies, while the sample taken met the criteria of 4 companies the number of observations for 9 years (2008-2016). The data obtained were analyzed using multiple linear regression analysis. The results showed that all hypotheses had a positive and significant effect based on the F test and t test. This means that both simultaneous and partial operational diversification and profitability have a positive and significant effect on the capital structure of state-owned banking companies listed on the Indonesia stock exchange.
PENGARUH DANA PIHAK KETIGA DAN RASIO KECUKUPAN MODAL TERHADAP PEMBIAYAAN MURABAHAH
Authors: Aziz Kresnhanto , Nurdiansyah Dian Hakip
Published: March 2021

This study aims to examine the effect of Third Party Funds and Capital Adequacy Ratio on Murabahah Financing in Indonesia from 2017-2019. This research method uses quantitative approach. The data used in this study comes from financial statements of sharia bank companies in Indonesia for the period of 2017-2019. Then, the data that has been obtained will be analyzed using multiple linear regression analysis and hypothesis testing consisting of the t test and f test with the help from SPSS 23 software. The sampling technique uses non probability sampling with purposive sampling technique. The results of statistical testing show that partially Third Party Funds has positive effect on Murabahah Financing and Capital Adequacy Ratio has positive effect on Murabahah Financing. Meanwhile, simultaneously Third Party Funds and Capital Adequacy Ratio has an effect on Murabahah Financing. Then, the coefficient of determination (R2) was 97,5%. This shows that Third Party Funds and Capital Adequacy Ratio variables can effect the Murabahah Financing by 97,5% and the remaining of 2,5% is influenced by other variables which are not used in this study. Keywords: Third Party Funds, Capital Adequacy Ratio, Murabahah Financing
ANALISIS PENERAPAN PSAK 34 DALAM PENGAKUAN PENDAPATAN PERUSAHAAN JASA KONTRUKSI PADA PT ARTERI CIPTA RENCANA
Authors: Pahlevi Lola Venna , Sari Ratna , Ahmad Hamzah
Published: March 2021

The aims of this research are to analyze the application of work contracts and the recognition of revenue for construstion service companies in accordance with PSAK 34 at PT Arteri Cipta Rencana. The data required in this study is secondary data, namely the financial statements of PT Arteri Cipta Rencana project for the period 2017-2019. Methods of data collection through interviews, observation and documentary. Data analysis techniques used by qualitative analysis.  This result of this research show that that the implementation of PSAK 34 at PT Arteri Cipta Rencana had executed project contracts sequentially in accordance with the prevailing tender regulations and realized the budget appropriately. The recognition of income and expenses carried out by PT Arteri Cipta Rencana is in accordance with PSAK 34 where revenue recognition for construction contracts is carried out using the completed contract method in the short-term period in the 2016-2018 financial statements. This is in accordance with PSAK 34 applicable in Indonesia. Short-term projects using the completed contract method minimize the risk of errors in estimating the specified value. The financial statements are considered to have met the criteria for the quality of financial reports well.Keyword: PSAK 34, Construction Company and Revenue Recognition
(شێواندنی وێنەی كورد وكوردستان لە سەرچاوە ئەمریكییەكاندا لە نێوان (1825-1914
Authors: Hussien Ahmed Saman
Published: March 2021

لە دوای ساڵی( 1822) ەوە، كە یەكەم نێردەی مسیۆنەری ئەمریكی هاتۆتە ناوچەكانی ژێر دەسەڵاتی دەوڵەتی عوسمانی . هەمیشە كورد یەكێك بووە لەو گەلانەی ناوچەكە ، كە جێی بایەخی ئەوان بووە و بە دەیان كاری رۆژنامەگەری و نووسین و لێكۆڵینەوە و یاداشتنامەیان لە بارەی كوردەوە نووسیوە، كە لە ئێستادا ئەم كارانە بەشێكی گرنگ لە كەرەستە و سەرچاوەكانی مێژووی, ئابوری , كۆمەڵایەتی وسیاسی كورد پێك دەهێنن. ئەم كارەی ئێمە هەوڵێكە بۆ كاركردن لەسەر ئەو سەرچاوە مێژوویانە ،بە تایبەتیش كاركردن لە سەر هەڵسەنگاندن و لەمەحەكدانی ئەو زانیارییە مێژوویانەی , كە لەو سەرچاوانەدا هاتوون ، بە تایبەتی ئەو زانیارییانەی كە شێواندنی تێدایە و كاریگەری نەرێنی دەكاتە سەر راستییە مێژووییەكان و رۆڵی دەبێت لە شێواندنی وێنەی كەسایەتی تاكی كورد و هەروەها واقعی مێژوویی ئەو سەردەمە. ئەم توێژینەوەیە لە پێنج تەوەرەی سەرەكی پێكدێت بەمجۆرە : تەوەرەی یەكەم تایبەتە بە قسەكردن لەسەر هاتنی ئەمریكییەكان بۆ ناوچەكانی كوردستان و ئەو كار وبەرهەمانەی ،كە ئەنجامیان داوە و زانیاری لە بارەی كورد و كوردستانەوە لە خۆ دەگرن .تەوەری دووەمیش، باسی ئەو شێواندنانە دەكات ، كە لەو سەرچاوانەدا لە بارەی ژیانی شارستانی كورد و كوردستانەوە لەو سەرچاوانەدا ئەنجامدراون و كورد وەك گەلێكی كێوی دەخەنەڕوو .تەوەرەی سێیەمیش , تەرخانكراوە بۆ تاوتوێكرنی ئەو زانیاریانەی , كە لەو سەرچاوانەدا لە بارەی دەرخستنی كورد وەكو گەلێكی توندوتیژ و شەڕانگێز و دەمارگیر هاتوون . تەوەرەی چوارەمیش , تایبەتكراوە بۆ گفتوگۆكردن دەربارەی ئەو سەرچاوانەی , كە كوردیان وەكو گەلێكی تاڵانچی و چەتەگەر خستۆتەڕوو . لە تەوەرەی پێنجەم و كۆتاییشدا, هەندێك لەو هەڵە مێژووییانە خراونەتە بەر باس و لێكۆڵینەوە ,كە لەو سەرچاوانەد لە بارەی مێژووی كوردەوە هاتوون .
Studi deskriptif prakik menyusui pada ibu pekerja industri dalam memberikan ASI di pabrik tekstil dan garmen
Authors: Afindaningrum Rochmanita Sandya , Emilia Ova
Published: March 2021

Menyusui memberi manfaat luar biasa bagi bayi karena ASI mengandung nutrisi yang penting dan terbaik untuk menunjang kesehatan, pertumbuhan, dan perkembangan bayi secara optimal .Meningkatnya ibu pekerja di Indonesia dapat mempengaruhi angka cakupan pemberian ASI ekslusif. Dukungan menyusui dapat meningkatkan konsentrasi ditempat bekerja karena berkurangnya kekhawatiran ibu terhadap nutrisi bayi sehingga produktivitas pekerja tinggi. Tujuan penelitian ini adalah untuk menggali secara mendalam dukungan yang diperoleh dalam memberikan  ASI pada ibu menyusui pekerja industri di pabrik tekstil dan garmen. Jenis penelitian iniadalah deskriptif kualitatif. Teknik pengambilan sampel menggunakan purposive sampling. Jumlah sampel pada penelitian ini adalah 26 informan. Penelitian dilakukan dengan wawancara. Hasil penelitian pada informan didapatkan bahwa dukungan yang diterima ibu adalah dukungan keluarga yang terdiri dari dukungan dengan memberikan bantuan fisik dan dukungan emosional. Ketika bekerja ibu menerima dukungan dari rekan kerja dan perusahaan.