• Title/Summary/Keyword: System Delay

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Application of Big Data and Machine-learning (ML) Technology to Mitigate Contractor's Design Risks for Engineering, Procurement, and Construction (EPC) Projects

  • Choi, Seong-Jun;Choi, So-Won;Park, Min-Ji;Lee, Eul-Bum
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.823-830
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    • 2022
  • The risk of project execution increases due to the enlargement and complexity of Engineering, Procurement, and Construction (EPC) plant projects. In the fourth industrial revolution era, there is an increasing need to utilize a large amount of data generated during project execution. The design is a key element for the success of the EPC plant project. Although the design cost is about 5% of the total EPC project cost, it is a critical process that affects the entire subsequent process, such as construction, installation, and operation & maintenance (O&M). This study aims to develop a system using machine-learning (ML) techniques to predict risks and support decision-making based on big data generated in an EPC project's design and construction stages. As a result, three main modules were developed: (M1) the design cost estimation module, (M2) the design error check module, and (M3) the change order forecasting module. M1 estimated design cost based on project data such as contract amount, construction period, total design cost, and man-hour (M/H). M2 and M3 are applications for predicting the severity of schedule delay and cost over-run due to design errors and change orders through unstructured text data extracted from engineering documents. A validation test was performed through a case study to verify the model applied to each module. It is expected to improve the risk response capability of EPC contractors in the design and construction stage through this study.

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A Study on the Establishment of the IDS Using Machine Learning (머신 러닝을 활용한 IDS 구축 방안 연구)

  • Kang, Hyun-Sun
    • Journal of Software Assessment and Valuation
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    • v.15 no.2
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    • pp.121-128
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    • 2019
  • Computing systems have various vulnerabilities to cyber attacks. In particular, various cyber attacks that are intelligent in the information society have caused serious social problems and economic losses. Traditional security systems are based on misuse-based technology, which requires the continuous updating of new attack patterns and the real-time analysis of vast amounts of data generated by numerous security devices in order to accurately detect. However, traditional security systems are unable to respond through detection and analysis in real time, which can delay the recognition of intrusions and cause a lot of damage. Therefore, there is a need for a new security system that can quickly detect, analyze, and predict the ever-increasing cyber security threats based on machine learning and big data analysis models. In this paper, we present a IDS model that combines machine learning and big data technology.

Design of a Delayed Dual-Core Lock-Step Processor with Automatic Recovery in Soft Errors (소프트 에러 발생 시 자동 복구하는 이중 코어 지연 락스텝 프로세서의 설계)

  • Juho Kim;Seonghyun Yang;Seongsoo Lee
    • Journal of IKEEE
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    • v.27 no.4
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    • pp.683-686
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    • 2023
  • In this paper, we designed a Delayed Dual Core Lock-Step (D-DCLS) processor where two cores operate same instructions with delay and the result is compared to mitigate soft errors and common mode failures in automotive electronic systems. Because D-DCLS does not know which core an error occurred in, each core must be recovered to the point before the error occurred, but complex hardware modifications are required to return all intermediate values on the pipeline stage. In this paper, in order for easy hardware implementation, all register values are saved to a buffer whenever a branch instruction is executed. When an error is detected, the saved register values are automatically restored, and then 'BX LR' instruction is executed to return to the last branch point. The proposed D-DCLS processor was designed using Verilog HDL and was confirmed to continue normal operation after automatically recovering error.

Research on RAM-C-based Cost Estimation Methods for the Supply of Military Depot Maintenance PBL Project (군직 창정비 수리부속 보급 PBL 사업을 위한 RAM-C 기반 비용 예측 방안 연구)

  • Junho Park;Chie Hoon Song
    • Journal of the Korean Society of Industry Convergence
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    • v.26 no.5
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    • pp.855-866
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    • 2023
  • With the rapid advancement and sophistication of defense weapon systems, the government, military, and the defense industry have conducted various innovative attempts to improve the efficiency of post-logistics support(PLS). The Ministry of Defense has mandated RAM-C(Reliability, Availability, and Maintainability-Cost) analysis as a requirement according to revised Total Life Cycle System Management Code of Practice in May 2022. Especially, for the project budget forecast of new PBL(Performance Based Logistics) business contacts, RAM-C is recognized as an obligatory factor. However, relevant entities have not officially provided guidelines or manuals for RAM-C analysis, and each defense contractor conducts RAM-C analysis with different standards and methods to win PBL-related business contract. Hence, this study aims to contribute to the generalization of the analysis procedure by presenting a cost analysis case based on RAM-C for the supply of military depot maintenance PBL project. This study presents formulas and procedures to determine requirements of military depot maintenance PBL project for repair parts supply. Moreover, a sensitivity analysis was conducted to find the optimal cost/utilization ratio. During the process, a correlation was found between supply delay and total cost of ownership as well as between cost variability and utilization rate. The analysis results are expected to provide an important basis for the conceptualization of the cost analysis for the supply of military depot maintenance PBL project and are capable of proposing the optimal utilization rate in relation to cost.

Near-Optimal Low-Complexity Hybrid Precoding for THz Massive MIMO Systems

  • Yuke Sun;Aihua Zhang;Hao Yang;Di Tian;Haowen Xia
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.18 no.4
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    • pp.1042-1058
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    • 2024
  • Terahertz (THz) communication is becoming a key technology for future 6G wireless networks because of its ultra-wide band. However, the implementation of THz communication systems confronts formidable challenges, notably beam splitting effects and high computational complexity associated with them. Our primary objective is to design a hybrid precoder that minimizes the Euclidean distance from the fully digital precoder. The analog precoding part adopts the delay-phase alternating minimization (DP-AltMin) algorithm, which divides the analog precoder into phase shifters and time delayers. This effectively addresses the beam splitting effects within THz communication by incorporating time delays. The traditional digital precoding solution, however, needs matrix inversion in THz massive multiple-input multiple-output (MIMO) communication systems, resulting in significant computational complexity and complicating the design of the analog precoder. To address this issue, we exploit the characteristics of THz massive MIMO communication systems and construct the digital precoder as a product of scale factors and semi-unitary matrices. We utilize Schatten norm and Hölder's inequality to create semi-unitary matrices after initializing the scale factors depending on the power allocation. Finally, the analog precoder and digital precoder are alternately optimized to obtain the ultimate hybrid precoding scheme. Extensive numerical simulations have demonstrated that our proposed algorithm outperforms existing methods in mitigating the beam splitting issue, improving system performance, and exhibiting lower complexity. Furthermore, our approach exhibits a more favorable alignment with practical application requirements, underlying its practicality and efficiency.

Design of Navigation Filter to Improve Tracking Performance in Radar with a Moving Platform (기동 플랫폼 탑재 레이다 추적 성능 향상을 위한 항법 필터 설계)

  • Hyeong-Jun Cho;Hyun-Wook Moon;Ji-Hoon An;Sung-Hwan Sohn
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.24 no.3
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    • pp.115-121
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    • 2024
  • As the radar mounted on a moving platform moves and rotates, the state of the radar's coordinate system also changes. At this time, in order to track target, the target's coordinates should be converted using the platform state measured from the sensor, and tracking performance may deteriorate due to causes such as sensor noise, communication delay, and sensor update cycle. In this paper, to minimize the degradation of tracking performance because of sensor error, we designed a navigation filter to estimate the state of the moving platform and analyzed the effect of improving tracking performance by applying the navigation filter through a simulation test. To design this navigation filter, three filter algorithms were applied and analyzed to confirm the effect of improving platform position and attitude performance for each filter, and the navigation filter designed by applying the highest performance filter algorithm was applied to a tracking simulation test. Finally we confirmed Improvement in tracking performance before and after applying navigation filters.

The Evaluation of the Radiation Dose and Image Quality Through the Change of the Tube Voltage in Cerebral CT Angiography (전산화단층촬영장치를 이용한 뇌 혈관조영 검사에서 관전압 변화에 따른 방사선량과 영상의 질 평가)

  • LEE, Ji-Won;Jung, Kang-Kyo;Cho, Pyong-Kon
    • Journal of radiological science and technology
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    • v.38 no.2
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    • pp.121-126
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    • 2015
  • To image diagnosis in neurovascular diseases using Multi-Detector Computed Tomography(MDCT), injected the same contrast material when inspecting Brain Computed Tomography Angiography(BCTA) to examine radiation dose and Image quality on changing Cerebral Artery CT number by tube voltage. Executed an examination with same condition[Beam Collimation $128{\times}0.6mm$, Pitch 0.6, Rotation Time 0.5s, Slice Thickness 5.0mm, Increment 5.0mm, Delay Time 3.0sec, Care Dose 4D(Demension ; D)] except for tube voltage on 50 call patients for BCTA and divided them into two groups (25 people for a group, group A: 80, group B: 120kVp). From all the acquired images, set a ROI(Region of Interest) on four spots such as left cerebral artery, right cerebral artery, posterior cerebral artery and cerebral parenchyma to compare quantitative evaluation, qualitative evaluation and effective dose after measuring CT number value from Picture Archiving Communications System(PACS). Evaluating images with CT number acquired from BCTA examination, images with 80 kVp was 18% higher in Signal to Noise Ratio and 19% in Contrast to Noise Ratio than those with 120 kVp. It was seen that expose dose was decreased by over 50% with tube voltage 80 kVp than with 120 kVp. Group A (25 patients) was examination with tube voltage 80kVp while group B with 120 kVp to examine radiation dose and Image quality. It is considered effective to inspect with lower tube voltage than with conventional high kVp, which can reduce radiation dose without any affect on diagnosis.

Studies on the Fracture Healing in the Alloxan treated Rabbits (Alloxan 투여 가토(家兎)에 대한 골절치유 실험)

  • Kim, Sung-Joon
    • The Korean Journal of Pharmacology
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    • v.7 no.1
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    • pp.53-65
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    • 1971
  • It is well known that diabetes mellitus is associated with metabolic derangements, such as hyper-glycemia, ketosis, glycosuria, and also widespread alterations in the blood vessels, kidneys, eyes, peripheral nerves and heart. It is also recognized that healing of skin wound is delayed in diabetics. In bone, according to Aegerter, osteopenia develops in diabetes mellitus and it is chiefly ascribed to overutilization of protein. Shim claims that total blood flow to the entire skeletal system is approximately 4 to 8 percent of resting cardiac output and blood supply to the skeletal system would be decreased on account of secondary arteriosclerotic changes in the diabetics. An adequate blood supply is an essential factor in the healing process of fracture, and disturbed blood flow, either local or systemic, will invariably delay union of the fragments or the fragments from being fused. As the author has encountered several cases of diabetics in whom healing of fracture was delayed or incomplete, this experimental study was undertaken to elucidate the effects of hyperglycemia and diabetes mellitus on the healing process of fracture. In this experiment adult albino rabbits, weighing about 2 kg. were used and divided into 6 groups. The femur of each animal was fractured surgically, and then the healing process of fracture was periodically checked by radiography at an interval of one week for a period of 6 weeks. Thereafter, all the rabbits were killed to obtain tissue preparation of the femur. The experimental groups were as follows; 1) Control group: Six rabbits sustained a surgical fracture to the femur, without being given any other treatment or drug. 2) Alloxan-treated group: For inducing diabetes, alloxan was given intravenously to 17 rabbits in various dose as follows; to 7 of them 40 mg/kg, to 6 rabbits 80 mg/kg and to 4 rabbits 120 mg/kg of body weight, respectively. 3) Insulin-treated group: Protamine-zinc insulin was injected subcutaneously to each of 6 rabbits in a daily dose of 1 unit per kilogram of body weight. 4) Group treated with insulin after alloxan: Four rabbits were given 80 mg of alloxan once and than 1 unit of insulin per kilogram of body weight daily. Another 5 rabbits were injected 1 unit of insulin per kg of body weight daily following administration of alloxan in a dose of 120 mg/kg. 5) Homotransplantation group: Following intravenous injection of alloxan in a dose of 120 mg/kg, 10 rabbits underwent homotransplantation of a short bone segment to the femur. Five of them were subsequently given 1 unit/kg of insulin daily. 6) Sugar-treated group: six rabbits were fed $15{\sim}20$ gm of sugar daily throughout the period of experiment. The results obtained are summarized as follows; 1. Blood sugar level and damage to the pancreatic islet increased proportionately when alloxan was given to the rabbits in various doses. No appreciable change could be observed in the islets when the blood sugar level was altered by either oral administration of sugar or subcutaneous injection of insulin. 2. Comparing with the control group, healing of fracture was delayed in the alloxan-treated group, while callus formation and periosteal reaction were shown to be more prominent in this group and subsequently, the ultimate osseous tissue formed at the fracture site was significantly smaller in amount and less compact. These findings were more marked as the amount of alloxan increased. 3. Administration of insulin prevented the delay in healing process of fracture in the rabbits with alloxan-induced hyperglycemia. In this case, the course and progression of fracture healing were almost similar to those of control group. 4. Union between the host bone and the fragment transplanted from other rabbit of the same species was more delayed in the group treated with alloxan alone than in the group to which insulin was administered after development of alloxan-induced diabetes. In both groups periosteal new bone developed from the ends of the host bone, above and below the transplanted fragment, and directly fused with failure of periosteal callus to bridge the adjacent ends of the host bone and the transplanted fragment. 5. The healing process of fracture was not inhibited by alteration in blood sugar level when the blood sugar was abnormally increased by excessive sugar intake or lowered by administration of insulin alone. The healing of fracture in these groups progressed similarly as in the control group. In brief summary, it appears that the healing process of fracture would be definitely disturbed in diabetic state brought about by damage to the pancreatic islet. As such an inhibition could be overcome with insulin, it seems that insulin plays an important role in healing of fracture, but alteration in blood sugar level alone does not modify healing process of fracture to significant degree.

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The Records and Archives Administrative Reform in China in 1930s (1930년대 중국 문서당안 행정개혁론의 이해)

  • Lee, Won-Kyu
    • The Korean Journal of Archival Studies
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    • no.10
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    • pp.276-322
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    • 2004
  • Historical interest in China in 1930s has been mostly focused on political characteristic of the National Government(國民政府) which was established by the KMT(中國國民黨) as a result of national unification. It is certain that China had a chance to construct a modern country by the establishment of the very unified revolutionary government. But, it was the time of expanding national crises that threatened the existence of the country such as the Manchurian Incident and the Chinese-Japanese War as well as the chaos of the domestic situation, too. So it has a good reason to examine the characteristic and pattern of the response of the political powers of those days. But, as shown in the recent studies, the manifestation method of political power by the revolutionary regime catches our attention through the understanding of internal operating system. Though this writing started from the fact that the Nationalist Government executed the administrative reform which aimed at "administrative efficiency" in the middle of 1930s, but it put stress on the seriousness of the problem and its solution rather than political background or results. "Committee on Administrative Efficiency(行政效率委員會)", the center of administrative reform movement which was established in 1934, examined the plan to execute the reform through legislation by the Executive Council(行政院) on the basis of the results of relevant studies. They claimed that the construction of a modern country should be performed by not political revolution anymore but by gradual improvement and daily reform, and that the operation of the government should become modern, scientific and efficient. There were many fields of administrative reform subjects, but especially, the field of records and archives adminstration(文書檔案行政) was studied intensively from the initial stage because that subject had already been discussed intensively. They recognized that records and archives were the basic tool of work performance and general activity but an inefficient field in spite of many input staff members, and most of all, archival reform bring about less conflicts than the fields of finance, organization and personnel. When it comes to the field of records adminstration, the key subjects that records should be written simply, the process of record treatment should be clear and the delay of that should be prevented were already presented in a records administrative meeting in 1922. That is, the unified law about record management was not established, so each government organization followed a conventional custom or performed independent improvement. It was through the other records administrative workshop of the Nationalist Government in 1933 when the new trend was appeared as the unified system improvement. They decided to unify the format of official records, to use marker and section, to unify the registration of receipt records and dispatch records and to strengthen the examination of records treatment. But, the method of records treatment was not unified yet, so the key point of records administrative reform was to establish a unified and standard record management system for preventing repetition by simplifying the treatment procedure and for intensive treatment by exclusive organizations. From the foundation of the Republic of China to 1930s, there was not big change in the field of archives administration, and archives management methods were prescribed differently even in the same section as well as same department. Therefore, the point at issue was to centralize scattered management systems that were performed in each section, to establish unified standard about filing and retention period allowance and to improve searching system through classification and proper number allowance. Especially, the problem was that each number system and classification system bring about different result due to dual operation of record registration and archives registration, and that strict management through mutual contrast, searching and application are impossible. Besides, various problems such as filing tools, arrangement method, preservation facilities & equipment, lending service and use method were raised also. In the process this study for the system improvement of records and archives management, they recognized that records and archives are the identical thing and reached to create a successive management method of records and archives called "Records and Archives Chain Management Method(文書檔案連鎖法)" as a potential alternative. Several principles that records and archives management should be performed unitedly in each organization by the general record recipient section and the general archives section under the principle of task centralization, a consistent classification system should be used by classification method decided in advance according to organizational constitution and work functions and an identical number system should be used in the process of record management stage and archive management stage by using a card-type register were established. Though, this "Records and Archives Chain Management Method" was developed to the stage of test application in several organizations, but it was not adopted as a regular system and discontinued. That was because the administrative reform of the Nationalist Government was discontinued by the outbreak of the Chinese-Japanese War. Even though the administrative reform in the middle of 1930s didn't produce practical results but merely an experimentation, it was verified that the reform against tradition and custom conducted by the Nationalist Government that aimed for the construction of a modern country was not only a field of politics, but on the other hand, the weak basis of the government operation became the obstacle to the realization of the political power of the revolutionary regime. Though the subject of records and archives administrative reform was postponed to the future, it should be understood that the consciousness of modern records and archives administration and overall studies began through this examination of administrative reform.

Field Study For The Improvement of Medication System and Method for Inpatients at General Hospital (입원환자의 투약체계와 방법의 개선을 위한 현장연구)

  • Yoo, Hyung-Sook;Kuwan, Young-Mi;Song, Mi-Sook;Kim, Hyung-Ae;Park, Kyung-Sook
    • Journal of Korean Academy of Nursing Administration
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    • v.1 no.1
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    • pp.147-211
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    • 1995
  • Medication is a kind of medical service and a therapeutic nursing function which takes large portion of nursing service and requires complicated procedures. So many different medical personnel should be involved and cooporate each other in order to accomplish medication. Medication is also a vital nursing service, So nurse feels heavy responsibi lity in that she gives medication to the patient finally, so she has much responsibility if medication error is happened. Therefore it seems very important to clarify the problem of medication system and method, and find the subculture of medication situation because it may promote nursing productivity. The study was conducted to 1. Describe and interpret medication situation. 2. Find out the problem of medication system and method and on alternatives. 3. Compare the medication system and method of hospitals which are located in Seoul with object hospital Ethnographic methodology was used to study medication situation by doing participant observation and interview of health care personnel. Ten nurses and three nurse aids were interviewed. Two residents and internists, two phamacists and two accountants were also interviewed. Data was obtained and analized according to Developmental Research Sequence introduced by Spradly. On the basis of this data the results were as follows. 1. The overall flow of medication system was devided into six stage : first, checking doctor's order : second writing doctor's order, : third, transfering slip into the related departments such as account department, pharmacy : fourth, distribution of medication from pharmacy to unit : fifth, identifing medication by nurses : and finally, medicating to the patient. Behaviorors have been under a lot of stress in that they have to do much works, especially paperworks, So too much time were needed. They also have been suffered interpersonal conflicts among health care personnel and role conflicts in the process of doing medication service. 2. In the process of checking order, the problem was that too much time was required for checking order and paperwork. The more the order changes the more the paperwork is. Nurses have been suffering difficulties in calling internist in order to get bill. Even if writing down slip for medication order is doctor's job, Sometimes nurse has been expected to write slip by doctors or nurse would write slip beacuse of two much complexities and efforts for calling doctors. If the slip were incorrect, much time complicated procedures were more required for correcting it. So delay of administering drug would be resulted consequently. Drugs were delivered from pharmacy to units by delivery agent and phamacist. But because drugs were delivered without arranging room number of patient. Nurse should rearrange drugs in order of the room number So it had made waste time and effort, and Even when emergency drugs were needed, Prompt delivery of drug was not easy because of many reasons. For nurses, it took too long in the identification of the right drug. Actually nurses have heavy burden when medication error happens because nurse is the final actor who gives medication to the patient, So every three shift nurse ought to check drugs as soon as every shift begins. That's why it took too much time due to repeated confirming procedure. When nurses had to go patient room in order to give medications, there were difficulties in watching patient until the patient take medicine correctly. So it was impossible to check every patient wheather he took medicine or not especially in hectic situation. 3. There were many hospitals in Seoul which have similar medication system and method as object hospital according to the results of questionaire. This means that many hospitals have been suffering srimilar problems which were identified in object hospital. 4. Recommendations for promoting simplification of medication system and method were the following : Redesigning of slip from two pieces of paper into one : early discharge announcement system, and slip confirming through computer and controlling of period of prescreption from one day to two or three days : designing personal drug storage box for each patient and using it. If nurses follow the recommendations, they will make medication short & simple, and also have enough time of direct nursing care 5. Even though there were many difficulties in medicating patients. Medication itself has been considered as a caring among nurses because it makes rapport between nurse and patient. So nurses had better accept medication as a portion of nusing service not a original portion of phamacist. There are some limits in this research in terms of confining to only one unit of one hospital, and treating it especially in view of nurses' aspects, So further researchs should be continnued from various kmds of viewpoints of doctors, phamacists and so on. ${\cdot\cdot\cdot}$. Especially esthnographic study of computerized medication system and method seems to be followed.

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