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Widarti, Hayuni Retno, Deni Ainur Rokhim, M. Muchson, Endang Budiasih, Sutrisno Sutrisno, Rico Wahyu Pratama et Moh Ilmanul Hakim. « Developing Integrated Triplet Multi-Representation Virtual Laboratory in Analytic Chemical Materials ». International Journal of Interactive Mobile Technologies (iJIM) 15, no 08 (23 avril 2021) : 119. http://dx.doi.org/10.3991/ijim.v15i08.21573.
Texte intégralRésumé :
<p>Technological developments have triggered the emergence of various kinds of learning media innovations. Learning media is a very important part of the learning process. In this study, researchers designed a learning media in the form of a virtual laboratory on the practicum material of the basics of analytical chemistry which is integrated with multi-representation triplets to create and describe the results of learning media.</p>The method used in this development was Research and Development (R&D) method using the 4-D (four-D) development model. Data collection used qualitative and quantitative data. The qualitative data were in the form of comments and suggestions from the validator, while the quantitative data were the validation questionnaire and legibility test. The results showed that the validation of the material obtained a percentage of 84% (very valid), media validation of 78% (valid), and the results of trials on correspondents obtained a percentage in the range 81-92% (very valid). It can be concluded that the virtual laboratory learning media on the analytical chemistry laboratory material with the integration of the developed multi-representation triplet explanations is feasible to use, especially in the practicum of the basics of analytical chemistry on the topic of group I cation analysis and argentometry. This shows that the virtual laboratory developed has the potential to support online practicum learning, and the macroscopic, submicroscopic, and symbolic depiction in the virtual laboratory can help the process of receiving information by students
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Romadhiyana Kisno Saputri et Akhmad Al-Bari. « PERSEPSI MAHASISWA TERHADAP PRAKTIKUM DARING MATA KULIAH KIMIA ANALISIS ». Jurnal Educatio FKIP UNMA 6, no 2 (23 décembre 2020) : 676–83. http://dx.doi.org/10.31949/educatio.v6i2.723.
Texte intégralRésumé :
During the COVID-19 pandemic period, every education unit requires an online learning process, not only for theoretical courses, but also for practical courses, including analytical chemistry practicum courses. Student perceptions of online lectures can help students in implementing the process lectures during the Covid 19 pandemic, because a good and correct lecture will help students improve their understanding and knowledge of students. This study aims to find out students perception about online practicum in analytical chemistry. This research is a qualitative descriptive study. The sample was taken using simple random sampling consisted of 45 students. Data were obtained using questionnaires and in-depth interviews. Student perceptions were seen from three aspects, teaching and learning process, the ability of lecturers, facilities and infrastructure which were assessed using a likert scale. The data analysis by qualitative analysis, consisting of data collection, data reduction, data presentation, and conclusion drawing. Student perceptions in all aspects have a mean of 64.95% so that students 'perceptions of online practicum in analytical chemistry are positive. Students' perceptions of teaching and learning aspects have a value of 69.57% which indicates a positive perception, on aspects of lecturer competence have a value. 77.90% which shows a positive perception of the infrastructure aspect has a value of 47.39% which indicates a positive perception.
Keywords: students perceptions; online practicum; Analytic Chemistry
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Rosita, Betti, et Ulfa Khairani. « ANALISIS LAMA WAKTU PELAYANAN LABORATORIUM DI RUMAH SAKIT UMUM DAERAH PASAMAN BARAT ». JURNAL KESEHATAN PERINTIS (Perintis's Health Journal) 5, no 1 (29 juin 2018) : 114–21. http://dx.doi.org/10.33653/jkp.v5i1.153.
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Hospital laboratory services is one of the activities in hospitals that support quality health services. One indicator of the success of health services in the field of clinical pathology laboratory services is the waiting time for laboratory services. The standard set for laboratory service outcome waiting time is ≤ 140 minutes for blood chemistry and routine blood. This research analyzed the service time of outpatient laboratory that conducted hematology and clinical chemistry examination in the laboratory of Pasaman Barat Hospital. This research is a type of descriptive analytic research that is quantitative and supported by qualitative using cross sectional approach. The result of the research showed that laboratory service time at RSUD Pasaman Barat fulfilled the standard (≤ 140 minutes) for hematology examination 33.94 minutes, clinical chemistry 83.92 minutes, hematology and clinical chemistry 98 minutes. Based on the results of this study, the stages that contribute to the length of time laboratory services for hematological examination lies in the pre analytical stage, for clinical chemistry examination is located at the analytical stage, as well as for hematology and clinical chemistry examination lies in the analytic stage as well as the factors that affect the length of time laboratory services are human resources that is in the ability of officers and infrastructure facilities
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Upadhyay, Hemant K., Sapna Juneja, Ghulam Muhammad, Ali Nauman et Nancy Awadallah Awad. « Analysis of IoT-Related Ergonomics-Based Healthcare Issues Using Analytic Hierarchy Process Methodology ». Sensors 22, no 21 (27 octobre 2022) : 8232. http://dx.doi.org/10.3390/s22218232.
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The objective of the present work is for assessing ergonomics-based IoT (Internet of Things) related healthcare issues with the use of a popular multi-criteria decision-making technique named the analytic hierarchy process (AHP). Multiple criteria decision making (MCDM) is a technique that combines alternative performance across numerous contradicting, qualitative, and/or quantitative criteria, resulting in a solution requiring a consensus. The AHP is a flexible strategy for organizing and simplifying complex MCDM concerns by disassembling a compound decision problem into an ordered array of relational decision components (evaluation criteria, sub-criteria, and substitutions). A total of twelve IoT-related ergonomics-based healthcare issues have been recognized as Lumbago (lower backache), Cervicalgia (neck ache), shoulder pain; digital eye strain, hearing impairment, carpal tunnel syndrome; distress, exhaustion, depression; obesity, high blood pressure, hyperglycemia. “Distress” has proven itself the most critical IoT-related ergonomics-based healthcare issue, followed by obesity, depression, and exhaustion. These IoT-related ergonomics-based healthcare issues in four categories (excruciating issues, eye-ear-nerve issues, psychosocial issues, and persistent issues) have been compared and ranked. Based on calculated mathematical values, “psychosocial issues” have been ranked in the first position followed by “persistent issues” and “eye-ear-nerve issues”. In several industrial systems, the results may be of vital importance for increasing the efficiency of human force, particularly a human–computer interface for prolonged hours.
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Raga, A. C., et J. Cantó. « Mixing layers in flows in star forming regions ». Symposium - International Astronomical Union 178 (1997) : 89–102. http://dx.doi.org/10.1017/s0074180900009268.
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There are now many observations of high velocity, molecular emission associated with outflows from young stars. This emission might come from molecules that are formed in the outflowing material, or from entrained, ambient molecular gas. The present paper explores the latter possibility, describing the efforts that have been made to model the “lateral entrainment” that occurs in the turbulent mixing layer formed along the edges of a jet-like flow (or, equivalently, at any interface between a fast moving flow and the surrounding environment). A simple, analytic approach based on model equations is used to provide a qualitative picture of the dynamical, thermal and chemical structure of such a turbulent mixing layer. Finally, a review of the efforts up to date of modelling the dynamics and chemistry of turbulent mixing layers is presented.
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Seo, Sang, et Dohoon Kim. « Study on Inside Threats Based on Analytic Hierarchy Process ». Symmetry 12, no 8 (29 juillet 2020) : 1255. http://dx.doi.org/10.3390/sym12081255.
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Insider threats that occur within organizations cause more serious damage than external threats. However, there are many factors that are difficult to determine, such as the definition, classification, and severity of security breaches; hence, it is necessary to analyze system logs and user behavior-based scenarios within organizations. The reality is that qualitative judgment criteria are different for everyone to apply, and there is no detailed verification procedure to compare them objectively. In this study, realistic insider threats were examined through the definition, classification, and correlation/association analysis of various human–machine logs of acts associated with security breaches that occur in an organization. In addition, a quantitative process and decision-making tool were developed for insider threats by establishing various internal information leakage scenarios. As a result, insider threats were assessed quantitatively and a decision-making process was completed that enabled case analysis based on several insider threat scenarios. This study will enable precise modeling of insider threats that occur in real organizations and will support an objective process and a decision-making system to establish a range of required information for security protection measures.
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Halliwell, BS, IBCLC, Hannah A., Ebony King, MD, Maggie Gonzalez-Matute, BS, Jeremy A. Kirksey, BS, Cheldy Martinez, BS, Micharri Pratts, BA, RN, Sivanah Ybarra, BSPH, Nikesha Williams, BS et Shervin Assari, MD, MPH. « “It’s Like the Elephant in the Room” A Qualitative Analysis of Racism in a U.S. High School ». World Journal of Educational Research 9, no 4 (17 août 2022) : p28. http://dx.doi.org/10.22158/wjer.v9n4p28.
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Identifying and addressing systemic racial oppression in the education system is a key component in confronting pervasive health and economic disparities for Black students. In this qualitative study, we conducted secondary analysis of existing data. Transcripts of interviews and focus group discussions belonged to 21 Black students in a charter school in Michigan in the year 2013. Open access data were downloaded from University of Michigan’s Inter-university Consortium for Political and Social Research (ICPSR) database in 2022. We used an inductive analytic approach to analyze the qualitative data for constructs related to experiences of structural racism. Three constructs that characterized students’ experiences of structural racism in the U.S. education system were found: (a) Lack of Color-conscious Curriculum; (b) Selective Cultural Erasure; and (c) The Demonstration of Racialized Power. For researchers, these data highlight a need for more studies on the effects of structural racism in the U.S. education system on educational, economic, and health outcomes. For administrative and policy makers, the results emphasize the need for educational initiatives that address deeply-rooted structural inequalities in the U.S. education system. This may include adoption of color-conscious curriculum and culturally responsive pedagogy, the utilization of restorative justice practices, and reparations for Black Americans.
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ElQasaby, Ahmed R., Fahad K. Alqahtani et Mohammed Alheyf. « State of the Art of BIM Integration with Sensing Technologies in Construction Progress Monitoring ». Sensors 22, no 9 (4 mai 2022) : 3497. http://dx.doi.org/10.3390/s22093497.
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The necessity for automatic monitoring tools led to using 3D sensing technologies to collect accurate and precise data onsite to create an as-built model. This as-built model can be integrated with a BIM-based planned model to check the project’s status based on algorithms. This article investigates the construction progress monitoring (CPM) domain, including knowledge gaps and future research direction. Synthesis literature was conducted on 3D sensing technologies in CPM depending on crucial factors, including the scanning environment, assessment level, and object recognition indicators’ performance. The scanning environment is important to determine the volume of data acquired and the applications conducted in the environment. The level of assessment between as-planned and as-built models is another crucial factor that could precisely help define the knowledge gaps in this domain. The performance of object recognition indicators is an essential factor in determining the quality of studies. Qualitative and statistical analyses for the latest studies are then conducted. The qualitative analysis showed a shortage of articles performed on 5D assessment. Then, statistical analysis is conducted using a meta-analytic regression model to determine the development of the performance of object recognition indicators. The meta-analytic model presented a good sign that the performance of those indicators is effective where [p-value is = 0.0003 < 0.05]. The study is also envisaged to evaluate the collected studies in prioritizing future works from the limitations within these studies. Finally, this is the first study to address ranking studies of 3D sensing technologies in the CPM domain integrated with BIM.
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Wulandari, Wulandari, Suci Siti Lathifah et Oding Sunardi. « IMPLEMENTASI PEMBELAJARAN BIOLOGI BAGI ANAK BERKEBUTUHAN KHUSUS DI SEKOLAH LUAR BIASA BAGIAN B (TUNARUNGU) SMALB DHARMA WANITA KOTA BOGOR ». Bioilmi : Jurnal Pendidikan 7, no 1 (1 janvier 2021) : 18–23. http://dx.doi.org/10.19109/bioilmi.v7i1.9495.
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This research is a qualitative research with descriptive analytic method. The purpose of this study was to describe an analyze learning at SMALB Dharma Wanita Kota Bogor. This research was carried out from February 2019 to Juli 2019 with several informan namely Biology Teacher 1, Principal, Biology Teacher 2, Parents Of Students, Students and Curriculum. This research was conducted with direct contact with the subject of research foun in the field and obtained two types of data, namely primary data derived from interviews and observations, as well as secondary data derived from study documentation, based on data analysis, biology learning in to 3 processes, bamely planning, implementation and evaluation. Biology learning planning at SMALB Dharma Wanita, namely the teacher holding a work meeting ( in house training) discusses the completeness of the administration of the teacher and strategies or methods that will be used by the class. The implementation of biology learning at SMALB Dharma Wanita consists of introductory, core and concluding activities. Evaluation of learning in SMALB Dharma Wanita consists of cognitive, affektive and psychomotor.
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Kumar, Nand Kishor. « Relationship Between Differential Equations and Difference Equation ». NUTA Journal 8, no 1-2 (31 décembre 2021) : 88–93. http://dx.doi.org/10.3126/nutaj.v8i1-2.44113.
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The study of Differential equations and Difference equations play animportant and significant role in many sciences. These equations are used as mathematical tool used in solving various problems in modeling,physics, chemistry,biology, anthropology, etc. or even in social studies. Differential equations are used to solve real life problems by approximation of numerical methods. Theory of Differential and Difference equations has been taught at all levels in high schools and at the universities for all students, including students majoring in Mathematics.
This is a micro –study in which the research is designed in an exploitative, qualitative, descriptive and analytic framework to analyze the differential-difference equations. In this study, theoretical concepts, descriptive, analytical and numerical methods about differential-difference equations which areclarified by related examples. This research article seeks to study the relationship between them.
The finite difference method for solving equations leads to difference equationtheory, developing a parallel between difference equations and differential equations. The first differences are related to the first derivatives. Difference equations are discrete versions of differential equations, and similarly differential equations are continuous versions of difference equations.
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Carlton, Robert A., Edward Orton, Charles E. Lyman et James E. Roberts. « Qualitative Analysis of Solid Phase Synthesis Reaction Products by X-ray Spectrometry ». Microscopy and Microanalysis 3, no 6 (novembre 1997) : 520–29. http://dx.doi.org/10.1017/s1431927697970409.
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Abstract: A novel method for the synthesis of polypeptides using polystyrene/divinylbenzene copolymers as solid supports has drawn the attention of medicinal, pharmaceutical, and agricultural chemists because of its utility in combinatorial chemistry and parallel synthesis. In this method, arrays of solid-phase organic synthesis experiments are conducted simultaneously thereby enabling the preparation of large numbers of novel compounds over a short time period. The analysis of organic compounds attached to polymer supports presents unique challenges to chemists. This study presents some results of the application of energy-dispersive X-ray spectrometry (EDS) in the environmental scanning electron microscope (ESEM) to this problem. EDS in the ESEM has the advantages of minimal sample size, speed, and simplicity because the analyses are performed without special specimen preparation. The progress of a two-step synthetic transformation was followed using EDS-ESEM by the presence of a sulfur peak in the first synthetic step and by a bromine peak in the second step. The synthetic products were also evaluated by infrared spectroscopy and by elemental analysis (ion chromatography). The agreement of the qualitative analysis among all three techniques was good. Analysis by EDS-ESEM not only complements current analytical techniques in solid phase synthesis; it also provides insight into the details of the synthetic transformation.
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Hoque, Muhammad, Saima Tasfia, Naser Ahmed et Biswajeet Pradhan. « Assessing Spatial Flood Vulnerability at Kalapara Upazila in Bangladesh Using an Analytic Hierarchy Process ». Sensors 19, no 6 (15 mars 2019) : 1302. http://dx.doi.org/10.3390/s19061302.
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Floods are common natural disasters worldwide, frequently causing loss of lives and huge economic and environmental damages. A spatial vulnerability mapping approach incorporating multi-criteria at the local scale is essential for deriving detailed vulnerability information for supporting flood mitigation strategies. This study developed a spatial multi-criteria-integrated approach of flood vulnerability mapping by using geospatial techniques at the local scale. The developed approach was applied on Kalapara Upazila in Bangladesh. This study incorporated 16 relevant criteria under three vulnerability components: physical vulnerability, social vulnerability and coping capacity. Criteria were converted into spatial layers, weighted and standardised to support the analytic hierarchy process. Individual vulnerability component maps were created using a weighted overlay technique, and then final vulnerability maps were produced from them. The spatial extents and levels of vulnerability were successfully identified from the produced maps. Results showed that the areas located within the eastern and south-western portions of the study area are highly vulnerable to floods due to low elevation, closeness to the active channel and more social components than other parts. However, with the integrated coping capacity, western and south-western parts are highly vulnerable because the eastern part demonstrated particularly high coping capacity compared with other parts. The approach provided was validated by qualitative judgement acquired from the field. The findings suggested the capability of this approach to assess the spatial vulnerability of flood effects in flood-affected areas for developing effective mitigation plans and strategies.
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Susilanigsih, Endang. « MODEL EVALUASI PRAKTIKUM KIMIA DI LEMBAGA PENDIDIKAN TENAGA KEPENDIDIKAN ». Jurnal Penelitian dan Evaluasi Pendidikan 16, no 1 (14 janvier 2013) : 234–48. http://dx.doi.org/10.21831/pep.v16i1.1115.
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Penelitian ini bertujuan untuk memperoleh model evaluasi program yang teruji, untuk mengevaluasi kualitas praktikum kimia. Pengembangan model evaluasi program terdiri atas empat variabel sebagai komponen model yaitu: (1) environmemt context yang dieksplanasi menjadi environment, laboratory work, technology and society; (2) evaluasi Input; (3) evaluasi process; dan (4) evaluasi result yang disesuaikan dengan praktikum kimia analisis dasar. Penetapan konstruk instrumen terdiri atas instrumen penilaian model dan instrumen penilaian kinerja mahasiswa dilakukan melalui pendapat: (1) pakar evaluasi; (2) pakar psikometri, dan (3) praktisi laboratorium. Subjek coba penelitian ini terdiri atas mahasiswa dan praktisi. Uji model evaluasi program dilakukan dengan uji: (1) utility; (2) feasibility; (3) proprietly; dan (4) accuracy. Uji kecocokan model untuk mengetahui reliability komponen program dan goodness of fit index menggunakan program Lisrel. Hasil pe-nelitian menunjukkan bahwa evaluasi program yang dikembangkan diberi nama model ECIPR sudah teruji memenuhi kriteria: (1) utility; (2) feasibili-ty; (3) proprietly; dan (4) accuracy reliability untuk komponen Environment context =0,8649, input=0,8429, process=0,7828, result=0,9560. Goodness of fit index: p = 0,107 RMSEA=0,051, GFI=0,910. Dampak implentasi model yang dikembangkan terbukti dapat meningkatkan kinerja mahasiswa, keterampilan dan pengalaman laboratorium mahasiswa sebagai sasaran program.Kata kunci: model evaluasi program, praktikum kimia, keterampilan laboratorium______________________________________________________________ THE EVALUATION MODEL OF THE CHEMISTRY PRACTICUM IN TEACHER EDUCATION INSTITUTIONSAbstract This study aims to produce a program evaluation model which is valid to evaluate the quality of chemistry practicum. The program evaluation model consists of four variables as model components,i.e:(1) the context environment which is elaborated into environment, laboratory work, technology, and society; (2) the input evaluation; (3) the process evaluation; and (4) the result evaluation adjusted to basic analytic chemistry practicum.The establishment of the instrument constructs, consisting of a model evaluation instrument and a student performance evaluation instrument, was based on the opinions of (1) evaluation experts, (2) psychometrics experts, and (3) laboratory practitioners. The subjects for tryout in this research consisted of students and practitioners. The test of the program evaluation model was carried out on the basis of: (1) utility, (2) feasibility, (3) propriety, and (4) accuracy. The model fit test to find out the reliability of the program components and the goodness of fit index used the LISREL program package. The calculation of the reliability coefficient of the instrument for the laboratory performance evaluation used the SPSS program based on the Generalizability coefficient model developed by Thorndike. The components of the variance were the person, rater, item, interactions of the person and rater, the person and item, the rater and item, and the interaction of the person, rater and item.The results of the study show that the ECIPR program evaluation model is valid and satisfies the criteria for: (1) utility, (2) feasibility, (3) propriety, and (4) accuracy. The indicator reliability of the component of environment context is 0.8649, that of the input is 0.8429, that of the process is 0.7828, and that of the result is 0.9560. The goodness of fit index is indicated by p = 0.107, RMSEA = 0.051, and GFI = 0.910. The generalizability coefficient of the qualitative analytic instrument is 0.8726 and that of the quantitative analytic instrument is 0.9384. The implementation of the ECIPR model has been proved capable of improving the students’ performances, which have effects on the improvement of their laboratory skills and experiences as the program target.Keywords: program evaluation model, chemistry practicum, laboratory skills
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Kazakov, S. P., et L. A. Suslova. « Development of preanalytical criteria assessment of quality of vacuum blood collection systems affecting clinical examination of patients ». Medical Immunology (Russia) 22, no 3 (21 mai 2020) : 585–98. http://dx.doi.org/10.15789/1563-0625-dop-1920.
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This paper presents comparative studies of preanalytical quality indices of vacuum gel systems (VGS) from four manufacturers, i.e., GL 795 (China), Vacuette (Austria), BD Vacutainer SST (USA) and Zdravmedtech (Russia). The analysis of the number of qualitative defects of the preanalytic phase of blood collection in vacuum gel tubes at the inpatient departments and in Department of Clinical Chemistry (preanalytic laboratory), in accordance with adopted criteria based on Russian industry standards, which are implemented with European indices of pre-analytic stage. The obtained results allowed us to identify a number of qualitative defects at pre-analytic stage for the vacuum gel systems from each manufacturer, including to summarize the data on number of these defects. Based on these results, the most common defects in each of the VGS presented by manufacturers are formulated. The results obtained can be used by manufacturers to improve the quality (structures) of the mentioned vacuum gel tubes.The results of the comparative characteristics of VGS of different manufacturers were evaluated by their influence on the indexes of hemolysis (IH), ictericity, lipemia. The resulting indices of ictericity and lipemia do not allow to use them as criteria for assessing quality of the gel systems. The frequency of IH occurrence in serum at > 50 conventional units in VGS of different manufacturers was studied. It was revealed, that IH in the range from 10 to 50 conventional units and more, can be used as a criterion of VGS quality.Comparison of routine biochemical parameters in VGS of different manufacturers, i.e., alanine aminotransferase, aspartate aminotransferase, direct bilirubin, lactate dehydrogenase (LDH), serum K+, was also carried out. It was found that the largest deviations from the average value were obtained for aspartate aminotransferase indices of more than 12.47% in Russian test tubes, and for direct bilirubin of more than 12.25% in Chinese test tubes and more than 9.15% in Russian test tubes. The study showed influence of IH upon quantitative values of lactate dehydrogenase for VGS from different manufacturers. It is proposed to use lactate dehydrogenase as an analyte. On this basis, it is possible to recommend a comparative quality assessment of vacuum gel systems, with IH cutoff level of more than 19 conventional units. It remains relevant to search for other analytes that can be used to assess the quality of VGS from different manufacturers. Some areas of research in biochemical testing are outlined. Preliminary data are obtained on usage of vacuum systems from different manufacturers for quality assessment, as well as conditions for performing these tests, along with the level of the hemolysis index of more than 10 conventional units.
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Santos, Stéfanno Souza, Isis Gomes Dos Santos, Cinara Vanconcelos Da Silva et Edith C. L. Cazedey. « Qualitative Analysis of Hydroxyurea ». Drug Analytical Research 4, no 1 (16 juillet 2020) : 18–21. http://dx.doi.org/10.22456/2527-2616.100682.
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Hydroxyurea (HU) is a cytostatic agent with antineoplastic activity and it has great clinical efficacy in the treatment of sickle cell disease. HU is part of the National Relation of Essential Medicines of Brazil and despite of its clinical importance, only the Portuguese, American and European Pharmacopoeias present monographs for this medicine. This study aimed to develop qualitative methods for identification and verification of purity of HU. For the HU identification, IR and UV spectroscopy were used, as well as TLC. The IR and UV spectra showed compatibility and the maximum absorption at 213 nm. For TLC, various pure or polarity gradient solvents were tested with results satisfactory for a mobile phase containing acetone and ethyl acetate (99:1, v/v). The replacement of the mobile phase generated less chemical waste, while minimizing the risks to the health of the operator, in accordance with the main concept of green analytical chemistry.
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Alkan, Fatma. « Analytical Chemistry Laboratory Qualitative Analysis Process Examination : Links Between Experimental Data and Calculations ». Jurnal Ilmiah Peuradeun 9, no 3 (30 septembre 2021) : 719. http://dx.doi.org/10.26811/peuradeun.v9i3.663.
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Analytical chemistry and qualitative-quantitative analysis practices have an important place in chemistry education. Operations such as experimental steps in volumetric analysis, reactions, and determining the amount of matter require problem-solving and higher-order thinking skills due to mathematical calculations. Students have difficulty and anxiety in making calculations in the volumetric analysis. This research aimed to examine the ability of chemistry teacher candidates to use the data obtained from the neutralization titration experiments in the calculation of the experimental result and to analyze the effects of information obtained from experiments on solving volumetric analysis problems. The sample of the study consisted of 13 chemistry teacher candidates studying in the chemistry teaching program of a state university. The research employed a descriptive survey model. Experiment data sheets and question solutions were taken as written answers. As a result of the research, it is noteworthy that the teacher candidates have problems in calculating the results of the experiment, and this has been overcome with increasing applications.
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Mak, D. K. « Carrier Concentrations and Drift Currents in the Depletion Region of a p–n Junction ». Surface Review and Letters 10, no 04 (août 2003) : 649–60. http://dx.doi.org/10.1142/s0218625x03005360.
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It has always been stated in electronics, semiconductor and solid state device textbooks that the hole drift and electron drift currents in the depletion region of a p–n junction are constant and independent of applied voltage (biasing). However, the explanations given are qualitative and unclear. We extrapolate the existing analytic theory of a p–n junction to give a quantitative explanation of why the currents are constant. We have also shown that the carrier concentrations in the depletion region, as depicted in some of the textbooks, are incorrect, and need to be revised. Our calculations further demonstrate that in reverse biasing, both hole and electron carrier concentrations each experience a local maximum and a local minimum, indicating that their diffusion currents change directions twice within the depletion region.
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Anim-Eduful, Benjamin, et Kenneth Adu-Gyamfi. « Chemistry students’ conceptual understanding of organic qualitative analysis ». Pedagogical Research 7, no 4 (6 août 2022) : em0132. http://dx.doi.org/10.29333/pr/12307.
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Toby, Sidney. « What's Present ? Qualitative Analysis Problems in General Chemistry ». Journal of Chemical Education 72, no 11 (novembre 1995) : 1008. http://dx.doi.org/10.1021/ed072p1008.
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Syamsuri, Syofi Aruni Mafaza et Imam Kamaluddin. « Strategi dalam Menciptakan Falah dengan Pendekatan Rasionalitas Ekonomi Ibnu Thufail : Telaah Kitab Hayy bin Yaqzan ». MALIA (TERAKREDITASI) 12, no 2 (2 septembre 2021) : 209–24. http://dx.doi.org/10.35891/ml.v12i2.2624.
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In the middle ages, the renaissance became the starting point for human awakening as a creature free from the constraints of tradition, culture and religion. The theory of rationality is more dominant or commonly called secularism, which separates religion and reason. This concept impacts on the principle that reason has no authority over revelation. So that the human condition in realizing welfare always justifies all means, unconsciously it has made damage to natural resources which has an impact on scarcity of goods (scharcity). By using a descriptive analytic method and a qualitative approach that analyzes the book "Hayy bin Yaqzan" by Ibn Thufail's masterpiece, which combines reason and religion. Finally, this article presents several concepts of economic rationality which are believed to be capable of creating equality. Some of the principles outlined in the book are the principles of ta'awun in utilizing natural resources, adaptive and creative as well as the support of good science and technology. Apart from that, he also provides strategies in creating welfare that can only be achieved by practicing the value of economic rationality by measuring the level of efficiency in fulfilling satisfaction without neglecting the balance of the surrounding nature.
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Souza Andrada Anconi, Amanda Carolina, Maísa Martins Monteiro et Cleber Paulo Andrada. « Separation and Qualitative Analysis of Carbonate, Phosphate and Chromate Anions in Qualitative Inorganic Courses ». Educación Química 29, no 4 (10 octobre 2018) : 49. http://dx.doi.org/10.22201/fq.18708404e.2018.4.65228.
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In the present work, our experience with a new methodology for separation and characterization of carbonate, phosphate and chromate anions is discussed. Since 2014 this laboratory experiment has been applied in undergraduate Chemistry courses in University of Lavras, Brazil, has shown to be satisfactory along Qualitative Inorganic or Analytical courses. In order to understand and to discuss the experiment, concepts involving equilibria of precipitation, acidity and basicity, liquid-liquid extraction, as well as the notions of solubility, phases distribution of solutes, and distribution diagram of the species were explored.
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Temel, Senar, et Özgür Özcan. « Students’ Understanding of Quantum Numbers : A Qualitative Study ». SHS Web of Conferences 48 (2018) : 01002. http://dx.doi.org/10.1051/shsconf/20184801002.
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Quantum physics involves counterintuitive abstract concepts and complex mathematical procedures that are difficult to understand by physics and chemistry students at university level. This study employs case study- one of the methods of qualitative study- and it aims to determine the difficulties prospective chemistry and physics teachers encounter in understanding quantum numbers. 17 students in total were included in the study. The data were collected via a test of three open-ended questions developed by the researchers. The collected data were then analysed by using the content analysis method. It was found accordingly that both prospective chemistry teachers and prospective physics teachers had difficulties in understanding quantum numbers. The findings obtained in this study were compared with the ones obtained in similar studies and were discussed accordingly.
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Wang, Chia-Nan, Hsiung-Tien Tsai, Van Thanh Nguyen, Viet Tinh Nguyen et Ying-Fang Huang. « A Hybrid Fuzzy Analytic Hierarchy Process and the Technique for Order of Preference by Similarity to Ideal Solution Supplier Evaluation and Selection in the Food Processing Industry ». Symmetry 12, no 2 (2 février 2020) : 211. http://dx.doi.org/10.3390/sym12020211.
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Selecting suppliers plays an important role in improving efficiency of supply chains. In the field of extraction of vegetable oil, one of the main submaterials is hexane solvent. Choosing a supplier of hexane solvent is a multicriteria decision-making task that decision-makers must have an understanding of the quantitative and qualitative elements for assessing the symmetrical impact of the criteria to reach the most accurate result. In this paper, the authors suggest a multicriteria decision-making (MCDM) model for N-hexane solvent (C6H14) supplier evaluation and selection for vegetable oil production. All criteria affecting to the hexane solvent supplier evaluation and selection process are defined by experts. Then, a fuzzy analytic hierarchy process (FAHP) multicriteria comparative analysis method has been applied for determining the weight of all criteria. Finally, the technique for order of preference by similarity to ideal solution (TOPSIS) was applied to select the optimal hexane solvent supplier. As a result, decision making unit 003 (DMU3) is the optimal supplier. The contribution of this research is to propose an MCDM model for hexane solvent supplier selection in the food industry. The work also proposed a useful guideline for supplier evaluation and selection processes in other industries.
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Iqbal, Zafar, Jorge E. Macías-Díaz, Nauman Ahmed, Aqsa Javaid, Muhammad Rafiq et Ali Raza. « Analytical and Numerical Boundedness of a Model with Memory Effects for the Spreading of Infectious Diseases ». Symmetry 14, no 12 (1 décembre 2022) : 2540. http://dx.doi.org/10.3390/sym14122540.
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In this study, an integer-order rabies model is converted into the fractional-order epidemic model. To this end, the Caputo fractional-order derivatives are plugged in place of the classical derivatives. The positivity and boundedness of the fractional-order mathematical model is investigated by applying Laplace transformation and its inversion. To study the qualitative behavior of the non-integer rabies model, two steady states and the basic reproductive number of the underlying model are worked out. The local and global stability is investigated at both the steady states of the fractional-order epidemic model. After analytic treatment, a structure-preserving numerical template is constructed to numerically solve the fractional-order epidemic model. Moreover, the positivity, boundedness and symmetry of the numerical scheme are examined. Lastly, numerical experiment and simulations are accomplished to substantiate the significant traits of the projected numerical design. Consequences of the study are highlighted in the closing section.
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Oliveri, Paolo, Cristina Malegori, Eleonora Mustorgi et Monica Casale. « Qualitative pattern recognition in chemistry : Theoretical background and practical guidelines ». Microchemical Journal 162 (mars 2021) : 105725. http://dx.doi.org/10.1016/j.microc.2020.105725.
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Zhang, Xuelong, Hui Wang, Jiangxia Nan, Yuxi Luo et Yanling Yi. « Modeling and Numerical Methods of Supply Chain Trust Network with the Complex Network ». Symmetry 14, no 2 (25 janvier 2022) : 235. http://dx.doi.org/10.3390/sym14020235.
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Finding reliable partners is the key to supply chain management. However, the symmetrical evaluation of enterprise trust is complex, so the decision-makers must understand its quantitative and qualitative characteristics in order to realize a reasonable evaluation. Based on the analysis of the causes and influencing factors of supply chain trust, this paper constructed four primary indexes and 16 secondary indexes to define enterprise trust, and used analytic network process (ANP) to evaluate and rank the indicators. Then, the paper constructed a supply chain directed weighted trust evolution network model based on complex network theory, integrated trust into the network with edge weights, and put forward the merit index of comprehensive node degree, weight, and efficiency to study the supply chain network evolution. The simulation results show that the node degree distribution in the trust evolution network conforms to the power-law distribution rule, and the trust evolution model of the complex network has obvious scale-free characteristics, which effectively avoid the situation that the node influence is too high due to the excessive strength of a single index. At the same time, it can quickly evaluate the node influence of the directed weighted complex network, and provide certain practical value for the node trust prediction of the supply chain network.
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Christian, Gary D. « Evolution of Analytical Sciences in the United States : A Historical Account ». Annual Review of Analytical Chemistry 13, no 1 (12 juin 2020) : 475–96. http://dx.doi.org/10.1146/annurev-anchem-091119-120456.
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The current teaching and practice of analytical chemistry reflect the evolution of measurement science over time. Qualitative and quantitative measurements can be traced back to prebiblical times, have been important throughout human history, and today are key to the functioning of a modern society. This review is designed to provide a brief overview of the evolution of analytical science and a summary of the evolution, development, and growth of analytical chemistry in the United States, with emphasis on developments up to the mid-twentieth century. Some degree of emphasis is placed on early centers of analytical chemistry and contributions of pioneers of analytical chemistry within the United States. The evolution of journals, early textbooks, and reference books on analytical chemistry as well as developments in analytical chemistry curricula in the United States are traced.
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Daniel Tan, Kim-Chwee, Ngoh-Khang Goh, Lian-Sai Chia et David F. Treagust. « Secondary Students' Perceptions about Learning Qualitative Analysis in Inorganic Chemistry ». Research in Science & ; Technological Education 19, no 2 (novembre 2001) : 223–34. http://dx.doi.org/10.1080/02635140120087740.
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Parga-Lozano, Diana Lineth, et William Fernando Moreno-Torres. « Conocimiento didáctico del contenido en química orgánica : Estudio de caso de un profesor universitario ». Revista Electrónica Educare 21, no 3 (28 août 2017) : 1. http://dx.doi.org/10.15359/ree.21-3.3.
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From Science Education, the Pedagogical Content Knowledge (PCK) is making an important contribution to the analysis of teacher training and the improvement of professionals. As such, a study was conducted to characterise the PCK of a teacher holding a degree in chemistry teaching; he teaches organic chemistry concepts at a higher education institution. The research involved a case study and was qualitative in nature; document analysis was also used as an analytical technique; besides, information was collected by use of Representations of Content (ReCo), Pedagogical and Professional Experience Repertoires (PaP-eR), document analysis of the participating teacher’s work, classroom observation, and interviews. With these tools, we were able to determine the strengths and weaknesses of the participating teacher, and from there, to infer aspects that needed improving in training undergraduates in chemistry. I found that, in this case, the teacher sees himself as chemist and not as chemistry teacher (i.e. there is a lack of professional identity); perhaps, because it is the dominant factor in his disciplinary knowledge at the expense of topics related to the knowledge of school context, as well as historical-epistemological and psycho-pedagogical knowledge. The latter indicates, as a characteristic of the participant’s PCK, that this PCK is incipient due to the disarticulation of its components, which weakens the teaching of organic chemistry concepts. This suggests the need to strengthen the initial training of teachers in their role as teaching professionals, and to integrate components of the PCK.
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Shamsulbahri, Mohamad Mahathir, et Norehan Zulkiply. « EXAMINING THE EFFECT OF DIRECTED ACTIVITY RELATED TO TEXTS (DARTs) AND GENDER ON STUDENTS’ ACHIEVEMENT IN QUALITATIVE ANALYSIS IN CHEMISTRY ». Malaysian Journal of Learning and Instruction 18, Number 1 (31 janvier 2021) : 157–81. http://dx.doi.org/10.32890/mjli2021.18.1.7.
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Purpose – The present study examined the effect of Directed Activity Related to Texts (DARTs) and gender on students’ achievement in Chemistry. The present study focused on the qualitative analysis component of Chemistry which has been perceived as being most difficult among students. Methodology – The study involved 120 form four science stream students from two local fully residential schools. In a quasi-experiment, participants studied the qualitative analysis of salt topic using one of these three instructional methods: Experiment, DARTs, and Combination of Experiment and DARTs; and later their knowledge about salt was tested. Findings – Results of a two-way independent ANOVA performed on the experiment data revealed a significant main effect of Instructional method—the mean scores for the combined method group was the highest, followed by the DARTs group and then the Experiment group. Further analysis using an independent t-test showed that the difference in mean scores between the DARTs and Experiment groups was significant. It is argued that participants’ learning in the Combined method group might have been enhanced by the DARTs instructional method. The effect of gender and the interaction effect between the variables were not significant. Significance – The present findings provides experimental evidence regarding the role of the DARTs instructional method in enhancing qualitative analysis learning in Chemistry. The present findings also provide insights to educators on DARTs as an alternative methods of teaching and learning qualitative analysis topics in Chemistry. Keywords: directed activity related to texts, qualitative analysis, chemistry, students’ achievement, salt topic, gender.
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Hakim, Femiliana. « Efektifitas Metode Scramble Dalam Pembelajaran Pendidikan Agama Islam di SDN Balonggabus Sidoarjo ». eL Bidayah : Journal of Islamic Elementary Education 3, no 2 (30 septembre 2021) : 161–78. http://dx.doi.org/10.33367/jiee.v3i2.1917.
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Islamic religious education learning (PAI) at elementary school has been dominated teacher and is not conducted maximally. This causes students' attention less focused in the teaching and learning process. To overcme this problem, it needs an alternative learning method. This article is descriptive analytic using a qualitative approach. The data is collected used literature study. The research results indicate three things. The first is, the scramble method is a relatively new learning technique, it also makes students are actively involved in the teaching and learning process. The second is, PAI learning is still dominated by the teacher which causes students to be less active and resulted learning outcomes too low. The third is, the scramble method is very important to be applied in PAI learning for elementary schools. This is done to improve student learning outcomes and change the monotonous learning methods.
[Pembelajaran pendidikan agama Islam (PAI) pada jenjang sekolah dasar menunjukkan masih didominasi belum berlangsung secara maksimal. Hal ini menyebabkan perhatian siswa kurang fokus saat belajar di sekolah. Diperlukan metode pembelajaran alternatif untuk mengakhiri permasalahan ini. Artikel ini bersifat deskriptif-analitik dengan menggunakan pendekatan kualitatif. Pengumpulan datanya menggunakan studi kepustakaan. Hasil pembahasan tulisan ini menunjukkan kepada tiga hal. Pertama menunjukkan bahwa metode scramble adalah teknik pembelajaran yang tergolong baru dan mampu menjadikan siswa aktif dalam proses pembelajaran. Kedua adalah kondisi pembelajaran PAI selama ini masih didominasi oleh metode ceramah yang menyebabkan siswa kurang aktif sehingga hasil belajar siswa masih tergolong rendah. Ketiga adalah metode scramble semakin penting (urgent) untuk diterapkan dalam pembelajaran PAI pada sekolah dasar. Hal ini didorong keinginan untuk menaikkan hasil belajar siswa dan mengakhiri metode pembelajaran yang selama ini masih monoton]
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Velcárcel, M., S. Cárdenas et M. Gallego. « Qualitative Analysis Revisited ». Critical Reviews in Analytical Chemistry 30, no 4 (juillet 2000) : 345–61. http://dx.doi.org/10.1080/10408340008984164.
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Musumarra, Giuseppe, Giuseppe Scarlata, Giuseppe Cirma, Guido Romano, Silvana Palazzo, Sergio Clementi et Gianfranco Giulietti. « Qualitative organic analysis ». Journal of Chromatography A 350 (janvier 1985) : 151–68. http://dx.doi.org/10.1016/s0021-9673(01)93515-0.
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Trstenjak, Maja, Tihomir Opetuk, Hrvoje Cajner et Miro Hegedić. « Industry 4.0 Readiness Calculation—Transitional Strategy Definition by Decision Support Systems ». Sensors 22, no 3 (4 février 2022) : 1185. http://dx.doi.org/10.3390/s22031185.
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The digitization of the manufacturing industry, 10 years after the introduction of the Industry 4.0 concept, is still one of the most demanding tasks for the companies, especially for SMEs. As one of the biggest barriers in new business model implementation, the lack of strategy and workforce skills is frequently mentioned in the literature. The high level of investments it requires and the perception of high risks with unclear future benefits can be avoided with readiness factor calculation. This paper presents a novel model for readiness factor calculation, oriented to process planning and based on decision support systems. The model enables the definition of the optimal strategic plan for the digitization with the use of decision support systems (analytic hierarchy process) and through the use of statistical methods implemented within the model it minimizes the influence of human subjectivity and quantification of qualitative criteria. This innovative approach enables the understanding of the transition process to new technology-enabled business models, in this case oriented towards process planning. The useability and reliability of the model is proven in a case study of a metal machining company.
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Cao, Jie, Bowen He, Nan Qu, Jiaxin Zhang, Chaoqiang Liu, Yaowei Liu et Chin-Ling Chen. « Benefits Evaluation Method of an Integrated Energy System Based on a Fuzzy Comprehensive Evaluation Method ». Symmetry 15, no 1 (28 décembre 2022) : 84. http://dx.doi.org/10.3390/sym15010084.
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Building an integrated energy system (IES) is an excellent solution to environmental pollution and energy consumption currently. However, there are usually various IES configurations with different performances, and it is usually difficult for the decision-makers to select the most sustainable IES solution among multiple choices. In this paper, we attempt to design an evaluation method that considers the renewable energy and energy system model for evaluating the benefit of an IES. Firstly, this paper constructs an evaluation index system including four dimensions of technology, economy, environment, and society, based on the physical architecture of IES and its benefit influencing factors. It focuses on multiple energy sources or systems, and satisfies the overall evaluation of IES, resulting in accurate benefit evaluation results. Secondly, the subjective weight is determined by combining the triangular fuzzy number (TFN) and the analytic hierarchy process (AHP). The objective weight is determined by the entropy method. The combined weight is obtained by combining the subjective and objective weights, which solves the problem of the weight calculation error caused by the mutual influence between the indexes. Finally, the fuzzy comprehensive evaluation method is used to conduct the benefit evaluation of the IES, which solves the problem that the qualitative index cannot be calculated. This paper takes an IES project in a city in northern China as a case study. Through sensitivity analysis and comparative analysis, the reliability and feasibility of the evaluation results and proposed method are verified. The analysis results show that the model evaluation results are intuitive and consistent with reality, and the data information utilization rate is high.
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Valcárcel, Miguel, et Soledad Cárdenas. « Modern qualitative analysis ». TrAC Trends in Analytical Chemistry 24, no 6 (juin 2005) : 467. http://dx.doi.org/10.1016/j.trac.2005.04.008.
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Mukani. « KH. M. Mahsun Adnan dan Kontribusinya Bagi Perkembangan MI Al-Adnani Kayangan Diwek Jombang ». eL Bidayah : Journal of Islamic Elementary Education 3, no 2 (30 septembre 2021) : 145–60. http://dx.doi.org/10.33367/jiee.v3i2.1872.
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The madrasa role has long been recognized by community. Based on Law Number 20 of 2003 concerning National Education System, madrasa is a national education sub-system. This article is descriptive-analytic with a qualitative approach. The data was collected through interviews, documentation and observation. The data then analyzed by non-statistics, such as data reduction, data presentation and conclusion drawing. The study describes a brief biography of KH. M. Mahsun Adnan, he was born in Nglaban, he studied at Tebuireng, after that he studied at PGA. After graduating, he then continued his study at Undar and then dedicated himself to da'wah and education until his death. The second focus is the struggle of KH. M. Mahsun Adnan toward Al-Adnani Islamic Elementary School Jombang, starting from being a pioneer, becoming the head of a madrasa, teaching in it and fighting to make the madrasa run up. So far, Al-Adnani Islamic Elementary School Jombang shows its existence continuesly in bringing forword the community arround through education.
[Peran madrasah telah lama diakui oleh masyarakat. Madrasah berdasarkan UU Nomor 20 Tahun 2003 tentang Sisdiknas adalah sebagai sub sistem pendidikan nasional. Artikel ini berjenis deskriptif-analitik dengan pendekatan kualitatif. Pengumpulan data melalui wawancara, dokumentasi dan observasi. Analisis data menggunakan non-statistik, yaitu reduksi data, penyajian data dan pengambilan kesimpulan. Pembahasan tulisan ini mendeskripsikan biografi singkat KH. M. Mahsun Adnan, mulai lahir di Dusun Nglaban, menimba ilmu ke Tebuireng, PGA dan kuliah di Undar lalu mengabdikan diri bagi dakwah dan dunia pendidikan hingga wafatnya. Fokus kedua adalah perjuangan KH. M. Mahsun Adnan kepada MI Al-Adnani Kayangan, mulai dari menjadi merintis, menjadi kepala madrasah, mengajar di dalamnya hingga berjuang agar madrasah tersebut tetap berkiprah. Hingga sekarang, MI Al-Adnani Kayangan tetap menunjukkan eksistensi dalam memajukan warga masyarakat sekitar melalui dunia pendidikan]
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Wu, Fengpei, Xiang Su, Young Seok Ock et Zhiying Wang. « Personal Credit Risk Evaluation Model of P2P Online Lending Based on AHP ». Symmetry 13, no 1 (5 janvier 2021) : 83. http://dx.doi.org/10.3390/sym13010083.
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With the rapid development of the P2P (peer-to-peer) online lending industry, which is facing significant credit risk, personal credit evaluation is an important method to reduce credit risk. Based on the various indexes of personal credit risk evaluation of domestic and foreign commercial banks, and according to the characteristics of P2P online lending, this paper analyzes the factors that affect the credit risk of P2P online borrowers, introduces the unique risk factors in the field of Internet information, and constructs an index system of personal credit risk evaluation of P2P online lending, which combines qualitative and quantitative indexes, including six major indexes and 21 small indexes. It then quantifies each index and defines the judgment standard of the evaluation results. Using analytic hierarchy process (AHP), expert scoring method, and fuzzy comprehensive evaluation method, this paper establishes a personal credit risk evaluation model of P2P online lending based on AHP method. The public information of two borrowers on the “PaiPai Lending” platform are selected for experimental verification. The results show that the improved personal credit risk evaluation model has better applicability and can evaluate the borrower’s credit status more scientifically, accurately, and comprehensively; thus, it is an effective method of personal credit risk evaluation of P2P online lending.
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Kurkina, Oxana, et Efim Pelinovsky. « Nonlinear Transformation of Sine Wave within the Framework of Symmetric (2+4) KdV Equation ». Symmetry 14, no 4 (24 mars 2022) : 668. http://dx.doi.org/10.3390/sym14040668.
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This paper considers the transformation of a sine wave in the framework of the extended modified Korteweg–de Vries equation or (2+4) KdV, which includes a combination of cubic and quintic nonlinearities. It describes the internal waves in a medium with symmetric vertical density stratification, and all the considerations in this study are produced for the reasonable combinations of the signs of the coefficients for nonlinear and dispersive terms, provided by this physical problem. The features of Riemann waves—solutions of the dispersionless limit of the model—are described in detail: The times and levels of breaking are derived in an implicit analytic form depending on the amplitude of the initial sine wave. It is demonstrated that the shock occurs at two (for small amplitudes) or four (for moderate and large amplitudes) levels per period of sine wave. Breaking at different levels occurs at different times. The symmetric (2+4) KdV equation is not integrable, but nevertheless it has stationary solutions in the form of traveling solitary waves of both polarities with a limiting amplitude. With the help of numerical calculations, the features of the processes of a sinusoidal wave evolution and formation of undular bores are demonstrated and analyzed. Qualitative features of multiple inelastic interactions of emerging soliton-like pulses are displayed.
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Watts, Field M., et Solaire A. Finkenstaedt-Quinn. « The current state of methods for establishing reliability in qualitative chemistry education research articles ». Chemistry Education Research and Practice 22, no 3 (2021) : 565–78. http://dx.doi.org/10.1039/d1rp00007a.
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The tradition of qualitative research drives much of chemistry education research activity. When performing qualitative studies, researchers must demonstrate the trustworthiness of their analysis so researchers and practitioners consuming their work can understand if and how the presented research claims and conclusions might be transferable to their unique educational settings. There are a number of steps researchers can take to demonstrate the trustworthiness of their work, one of which is demonstrating and reporting evidence of reliability. The purpose of this methodological review is to investigate the methods researchers use to establish and report reliability for chemistry education research articles including a qualitative research component. Drawing from the literature on qualitative research methodology and content analysis, we describe the approaches for establishing the reliability of qualitative data analysis using various measures of inter-rater reliability and processes including negotiated agreement. We used this background literature to guide our review of research articles containing a qualitative component and published in Chemistry Education Research and Practice and the Journal of Chemical Education from the years 2010 through 2019 for whether they report evidence of reliability. We followed this by a more in-depth analysis of how articles from the years 2017 through 2019 discuss reliability. Our analysis indicates that, overall, researchers are presenting evidence of reliability in chemistry education research (CER) articles by reporting reliability measures, describing a process of negotiated agreement, or mentioning reliability and the steps taken to demonstrate it. However, there is a reliance on reporting only percent agreement, which is not considered an acceptable measure of reliability when used on its own. In addition, the descriptions of how reliability was established were not always clear, which may make it difficult for readers to evaluate the veracity of research findings. Our findings indicate that, as a field, CER researchers should be more cognizant of the appropriateness of how we establish reliability for qualitative analysis and should more clearly present the processes by which reliability was established in CER manuscripts.
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Pascher, Ute, Melanie Roski et Brigitte Halbfas. « Entrepreneurial aspirations and start-up motives of women chemists in Germany ». International Journal of Gender and Entrepreneurship 7, no 3 (14 septembre 2015) : 272–90. http://dx.doi.org/10.1108/ijge-03-2013-0026.
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Purpose – The purpose of this paper is to promote better understanding of different women entrepreneurs and self-employed women with regard to their educational level and field of study. Foremost, the aim is providing detailed knowledge about the phenomenon of women self-employed chemists in R & D sectors and throwing light not only on the single women but also on the general conditions they are working in and their opportunities to get ahead. Design/methodology/approach – The interdisciplinary research team followed an integrated research approach and combined qualitative with quantitative methods. By focussing on motives and causes of women self-employed chemists, this paper refers to the findings of two sub-studies, an online survey on self-employed (female and male) chemists in Germany and a qualitative study on the basis of biographical interviews tracing the professional biographies of women self-employed chemists. Moreover, the findings are analysed based on other sub-studies, like the analysis of the (start-up) conditions within the chemical industry and a discourse analysis of a well-known chemical periodical. Findings – It was found that the differences between female and male chemists turning self-employed or starting a business are less pronounced than the differences between male and female founders, in general. Research demonstrates that women chemists do have high qualifications and if they become entrepreneurs, the main cause for that is escaping their organisational employment. Being entrepreneurially active, women chemists might work more satisfactorily, at least they are able to surround the glass ceiling. Originality/value – This paper seeks to fill the gap of limited in-depth information on knowledge about female entrepreneurs and self-employed women with an academic background in chemistry. Focussing on one single field of study and profession of female entrepreneurs is, in that way, unique, as the research has looked on professionals who are not predestined for entry in entrepreneurship.
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Danczak, S. M., C. D. Thompson et T. L. Overton. « ‘What does the term Critical Thinking mean to you?’ A qualitative analysis of chemistry undergraduate, teaching staff and employers' views of critical thinking ». Chemistry Education Research and Practice 18, no 3 (2017) : 420–34. http://dx.doi.org/10.1039/c6rp00249h.
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Good critical thinking is important to the development of students and a valued skill in commercial markets and wider society. There has been much discussion regarding the definition of critical thinking and how it is best taught in higher education. This discussion has generally occurred between philosophers, cognitive psychologists and education researchers. This study examined the perceptions around critical thinking of 470 chemistry students from an Australian University, 106 chemistry teaching staff and 43 employers of chemistry graduates. An open-ended questionnaire was administered to these groups, qualitatively analysed and subsequently quantified. When asked to define critical thinking respondents identified themes such as ‘analysis’, ‘critique’, ‘objectivity’, ‘problem solving’, ‘evaluate’ and ‘identification of opportunities and problems’. Student respondents described the smallest number of themes whereas employers described the largest number of themes. When asked where critical thinking was developed during the study of chemistry students overwhelmingly described practical environments and themes around inquiry-based learning. When teaching staff were asked this question they commonly identified critiques, research, projects and practical environments to some extent. This research highlights that there is only limited shared understanding of the definition of critical thinking and where it is developed in the study of chemistry. The findings within this article would be of interest to higher education teaching practitioners of science and chemistry, those interested in development of graduate attributes and higher order cognitive skills (HOCS) and those interested in the student and employer perspectives.
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Galloway, Kelli R., Carlee Stoyanovich et Alison B. Flynn. « Students’ interpretations of mechanistic language in organic chemistry before learning reactions ». Chemistry Education Research and Practice 18, no 2 (2017) : 353–74. http://dx.doi.org/10.1039/c6rp00231e.
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Research on mechanistic thinking in organic chemistry has shown that students attribute little meaning to the electron-pushing (i.e., curved arrow) formalism. At the University of Ottawa, a new curriculum has been developed in which students are taught the electron-pushing formalism prior to instruction on specific reactions—this formalism is part of organic chemistry's language. Students then learn reactions according to the pattern of their governing mechanism and in order of increasing complexity. If students are fluent in organic chemistry's language, they should have lower cognitive load demands when learning new reactions, and be better positioned to connect the three levels of chemistry's triplet (i.e., Johnstone's triangle). We developed a qualitative research protocol to explore how students use and interpret the mechanistic language. Twenty-nine first-semester organic chemistry students were interviewed, in which they were asked to (1) explain a mechanism, given all the starting materials, intermediates, products, and electron-pushing arrows, (2) draw in arrows for a reaction mechanism, given the starting materials and products of each step, and (3) predict the product of a reaction step, given the starting materials and electron-pushing arrows for that step. To investigate the students’ ideas about mechanistic language rather than their knowledge of specific reactions, we selected reactions for the interview guide that had not yet been taught. Following transcription, we analyzed the interviews using constant comparative analysis to explore how students used and interpreted the mechanistic language. Four categories of student thinking emerged with electron movement underlying students’ thinking throughout the interviews. Herein, we discuss these categories, students’ interpretation of the symbolism, connections to learning theory, and implications for teaching, learning, and research.
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Braun, R. D. « General chemistry with qualitative analysis ; 2nd edition (Petrucci, Ralph ; Wismer, Robert K.) ». Journal of Chemical Education 65, no 8 (août 1988) : A214. http://dx.doi.org/10.1021/ed065pa214.1.
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Furlong, William R., Michael R. Quackenbush et Ramee Indralingam. « What Is That Colorless Solution ? A Qualitative Analysis Laboratory for General Chemistry ». Journal of Chemical Education 86, no 8 (août 2009) : 953. http://dx.doi.org/10.1021/ed086p953.
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Harshman, Jordan, et Ellen Yezierski. « Characterizing high school chemistry teachers' use of assessment data via latent class analysis ». Chemistry Education Research and Practice 17, no 2 (2016) : 296–308. http://dx.doi.org/10.1039/c5rp00215j.
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In this study, which builds on a previous qualitative study and literature review, high school chemistry teachers' characteristics regarding the design of chemistry formative assessments and interpretation of results for instructional improvement are identified. The Adaptive Chemistry Assessment Survey for Teachers (ACAST) was designed to elicit these characteristics in both generic formative assessment prompts and chemistry-specific prompts. Two adaptive scenarios, one in gases and one in stoichiometry, required teachers to design and interpret responses to formative assessments as they would in their own classrooms. A national sample of 340 high school chemistry teachers completed the ACAST.Vialatent class analysis of the responses, it was discovered that a relatively small number of teachers demonstrated limitations in aligning items with chemistry learning goals. However, the majority of teachers responded in ways consistent with a limited consideration of how item design affects interpretation. Details of these characteristics are discussed. It was also found that these characteristics were largely independent of demographics such as teaching experience, chemistry degree, and teacher education. Lastly, evidence was provided regarding the content- and topic-specificity of the characteristics by comparing responses from generic formative assessment prompts to chemistry-specific prompts.
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Xu, Zian, et Minshui Huang. « Improving Bridge Expansion and Contraction Installation Replacement Decision System Using Hybrid Chaotic Whale Optimization Algorithm ». Applied Sciences 11, no 13 (5 juillet 2021) : 6222. http://dx.doi.org/10.3390/app11136222.
Texte intégralRésumé :
Bridge expansion and contraction installation (BECI) has proved to be an essential component of the bridge structure due to its stability, comfort, and durability benefits. At present, traditional replacement technologies for modular type, comb plate type, and seamless type BECIs are widely applied worldwide. Nevertheless, it is unfortunate that the research conducted on decision-making (DM) approaches for the technical condition assessment and the optimal replacement plan selection of existing BECIs remain scarce, which results in the waste of resources and the increase in cost. Therefore, a BECI technical condition assessment approach, which contains specific on-site inspection regulations with both qualitative and quantitative descriptions, is proposed in this research, and a corresponding calculation program has been developed based on the MATLAB platform, which provides the basis for the necessity of replacement. Simultaneously, the hybrid chaotic whale optimization algorithm is designed and performed to improve and automate the process of optimal replacement plan selection under the assistance of the analytic hierarchy process (AHP), where both the achievement in consistency modification and the reservation of initial information are perused, and its superiority and effectiveness are verified via the comparative experimental analysis. The improved BECI replacement decision system is established, and the corresponding case study demonstrates that the proposed system in this research proves reasonable and feasible. The improved system can effectively assist bridge managers in making more informed operation and maintenance (O and M) decisions in actual engineering projects.
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Salleh, Muhamad Furkan Mat, Rose Amnah Abd Rauf, Rohaida Mohd Saat et Mohamad Hisyam Ismail. « Learners’ issues in the preparation and qualitative analysis of salts topics in chemistry : Teachers’ perspectives ». European Journal of Science and Mathematics Education 11, no 3 (1 juillet 2023) : 392–409. http://dx.doi.org/10.30935/scimath/12789.
Texte intégralRésumé :
This study examines learners’ issues in learning the preparation and qualitative analysis of salts topic from Malaysian chemistry teachers’ perspectives. The researchers adopted a qualitative design and conducted semi-structured interviews with sixteen informants who have experience of teaching chemistry for more than five years. They were selected via purposive sampling. Document analysis was conducted to verify and supplement findings obtained from the interviews. The study reports five issues that emerged from the data analysis: negative perceptions, dealing with the number of information, imagining abstract concepts, mastery of basic knowledge and solving problems, and fulfilling the grading criteria. The study results confirm the unanimity of past studies on students’ unfavorable views on these topics and their struggle in learning abstract concepts involved in the salts formation and analysis. Besides, students’ issues are also significantly rooted in having weak prior knowledge of salts, affecting their ability to solve related problems. The study suggested that teachers must practice various approaches and strategies deemed effective in aiding learners in learning and be more selective in choosing approaches tailored to the individual students’ issues in learning these topics in class.
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Xiang, Qian, Ying Gao et Shang Wen Yang. « Recent Advances of Application of Capillary Electrophoresis in Traditional Chinese Medicine Analysis ». Advanced Materials Research 634-638 (janvier 2013) : 1388–91. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.1388.
Texte intégralRésumé :
The capillary electrophoresis (CE) is a powerful analytical technique in analytical chemistry and bioanalytical chemistry due to its high resolution, minimal sample requirements and low operating costs. Recent advances of application of CE for the analysis of traditional Chinese medicine is critically reviewed in this paper. After a simple discussion of the mode of separation and detection, special attention is focused on application of CE techniques and strategies for the qualitative and quantitative analysis in traditional Chinese medicine.
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Lumme, Paavo O. « Thioacetamide in qualitative analysis ». Journal of Chemical Education 67, no 2 (février 1990) : 184. http://dx.doi.org/10.1021/ed067p184.2.
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