Earticle

RSS(rotary steerable system)는 시추 비트의 각을 변화시키거나 횡력을 가하여 즉각적인 방향제어가가능한 기술로써, 높은 굴진율로 시추기간을 단축시켜 시추비용을 절감할 수 있다는 장점을 갖고 있어 대규모의유·가스전 개발뿐만 아니라 셰일가스 등의 비전통자원개발에 널리 적용되고 있다. 본 연구에서는 RSS의 작동메커니즘에 관한 기술적 특징에 대해 고찰하고 시추 시험을 수행한 실험실 및 현장 프로젝트 사례를 소개하였다. 실험실 시험사례를 통해 RSS의 방향성 거동 예측이 가능함을 확인하였으며, 현장 적용사례 분석 결과 슬라이드없이 작업해 굴진율이 증가함으로써 시추시간이 단축됨을 확인하였다. 다양한 콘크리트 강도와 비트 특성에따른 방향성 거동 분석 결과는 향후 국내외 유전 개발 시 RSS를 이용한 방향성 시추 계획 수립 및 적용에활용할 수 있을 것으로 판단된다.

The rotary steerable system(RSS) is technically capable of controlling a direction during drilling bychanging angle of bits or applying lateral force. The RSS has an advantage which is reducing the drilling timedue to its high rate of penetration(ROP). RSS has been widely applied to develop oil and gas reservoir, as wellas unconventional resources such as shale gas. This study presents technical characteristics about mechanism ofthe RSS operating and introduces laboratory experimental cases and field projects. Laboratory tests show thatit is possible to predict directional behavior of RSS. Furhemore, field projects show that the drilling time is reducedby the increasing ROP since slide was not required. The results in the directional behavior by various concretestrength and bit characteristics can be used to build and apply to a directional drilling plan for oil and gas fielddevelopment.

As the automotive industry has recently undergone a rapidly changing trend, it is now evolving around software, a key component of the electrical and electronic systems that are directly involved in the various functions of a car. The automotive SPICE standards specific to automotive embedded software have emerged, differentiating it from the existing software development process standard ISO. Within the model, there is a separate HIS Scope, a key process that must be achieved by small and medium sized electric vehicle companies as a minimum standard for car supply requirements. Especially, in the testing stage, it takes a lot of resources for the work, which is a big burden for small and medium automotive electric part. In this paper, we proposed and implemented a method that automatically generates the test cases used in the software integration test process based on the UML sequence diagram. Through case studies, we can see how well the automatically generated test cases with the proposed tool chain meet the requirements of the HIS Scope. We confirmed that it is possible to use test resources efficiently in terms of rewriting test cases according to design change and revision issues. and the results of this study can contribute greatly to the activities of the study to comply with Automotive SPICE standards.

현재 우주산업은 정부주도에서 민간 주도의 시장으로의 뉴페이스 시대가 가속화되고 있다. 특히, 저궤도·초저궤도 군집위 성을 활용한 위성 네트워크가 기존 정지·중궤도 위성을 대체하며, 고성능 위성 보안모듈 수요가 증가하고 있다. 본 연구는 ESA 표준과 시뮬레이션을 통해 초저궤도 우주 환경을 분석하고, 상용 EEE 부품을 사용하는 보안모듈에 실제 방사선 방호 소 재를 적용해 방사선 흡수 선량 저감을 실험적으로 검증했다. Al 단일 소재 대비 복합 소재 차폐 하우징 설계로 비용과 제작 기간을 줄이면서 우주 방사선 피해를 효과적으로 감소시키는 방안을 제시하였다. 이 연구는 저궤도 및 초저궤도 위성의 상용 부품(COTS, Commercial off-the-shelf)기반 보안 모듈 내구성 및 적응성을 향상시켜 미래 군 및 상업용 위성시스템에 상용부 품 활용의 중요한 기반이 될 것이다.

The space industry is rapidly entering a new era, transitioning from a government-led model to a commercially driven market. In particular, satellite networks based on low Earth orbit (LEO) and very low Earth orbit (VLEO) constellations are replacing traditional geostationary and medium Earth orbit satellites, leading to a growing demand for high-performance satellite security modules. This study analyzes the VLEO space environment using ESA standards and simulations, and experimentally verifies the reduction of absorbed radiation dose by applying practical radiation shielding materials to security modules built with commercial off-the-shelf (COTS) EEE components. By designing a composite-material shielding housing instead of a single aluminum material, the proposed approach reduces cost and fabrication time while effectively mitigating space radiation effects.This research enhances the durability and adaptability of COTS-based security modules for LEO and VLEO satellites and provides an important foundation for expanding the use of commercial components in future military and commercial satellite systems.

본 연구는 웹 브라우저에서 실행되는 웹 UI의 동적 테스트를 위한 노코드(no-code) 기반 테스트케이스 및 시나리오 자동 생성 기법을 제안한다. 기존의 스크립트 작성이나 녹화 방식과 달리, 본 기법은 웹 브라우저에서 발생하는 이벤트를 감 지하여 관련 데이터를 자동으로 수집하고, 이를 기반으로 테스트케이스와 시나리오를 생성한다. 제안된 기법의 검증을 위해 자동 생성된 테스트케이스를 사용하여 재테스트를 실행한 결과, 수집 당시 테스트를 동일하게 재현할 수 있었으며 실행 결과 의 정확성도 확인되었다. 본 연구는 사람이 별도의 사전 작업 없이 동적 테스트를 자동 수행할 수 있는 가능성을 제시하며, 향 후 복잡한 사용자 인터랙션 처리영역까지 확장하여 복잡한 업무단위까지 확장할 수 있을 것이라 기대된다.

This research proposes a no-code-based test case and scenario generation technique for dynamic testing of web UIs running in a web browser. Unlike traditional scripting or recording methods, this method detects events occurring in a web browser, automatically collects relevant data, and generates test cases and scenarios based on them. To validate the proposed method, we ran retests using the automatically generated test cases and found that we were able to reproduce the same tests as when they were collected, and the accuracy of the execution results was confirmed. This study shows the possibility of automatically performing dynamic testing without any prior human intervention, and it is expected that it can be extended to complex user interaction processing areas and complex business units in the future.

자율주행차량(AV)의 기술 발전으로 실도로 내 자율주행이 가능해졌지만, 주변 요소로 AV 의 인지 범위 또는 능력이 제한되는 인지 음영으로 완전한 자율주행에 어려움이 있다. 오늘날 Lv 4+ 자율주행 테스트 시나리오를 개발하기 위해서는 실제 도로에서 발생할 수 있는 다양한 인지 음영 상황을 파악하고 대비 전략을 구상하는 것이 중요하다. 따라서, 본 연구는 미국 캘리 포니아 차량관리국(DMV)의 AV 사고 데이터를 통해 자율주행 모드 활성화 여부에 따라 AV와 일반차량의 사고 형태와 특성을 비교하고, AV 제어권 전환 데이터를 단계적으로 분류하여 인 지 음영으로 인한 제어권 전환의 유형과 실제 사례를 도출하였다. 분석 결과, AV의 안전 운전 기동으로 일반 차량과 다른 사고 유형이 나타났으며, 3가지 유형의 인지 음영 사례를 파악하였 다. 본 연구 결과는 Lv 4+ 자율주행 테스트 시나리오 개발의 중요한 기초자료가 될 것이며, 다양한 인지 음영이 고려된 테스트 시나리오를 통해 상황별 인지 음영을 해소하는 효율적인 전략을 마련할 수 있다. 이를 통해 실제 도로에서의 AV 주행 안전성을 효과적으로 평가하고 향상할 수 있을 것으로 기대된다.

With the advancement of autonomous vehicle (AV) technology, autonomous driving on real roads has become feasible. However, there are challenges in achieving complete autonomy due to perceptual blind areas, which occur when the AV’s sensory range or capabilities are limited or impaired by surrounding objects or environmental factors. This study aims to analyze AV accident patterns and safety issues of perceptual blind area that may occur in urban areas, with the goal of developing test scenarios for Level 4+ autonomous driving. It utilized AV accident data from the California Department of Motor Vehicles (DMV) to compare accident patterns and characteristics between AVs and conventional vehicles based on activation status of autonomous mode. It also categorized AV disengagement data to identify types and real-world cases of disengagements caused by perceptual blind areas. The analysis revealed that AVs exhibit different accident types due to their safe driving maneuvers, and three types of perceptual blind area scenarios were identified. The findings of this study serve as crucial foundational data for developing Level 4+ autonomous driving test scenarios, enabling the design of efficient strategies to mitigate perceptual blind areas in various scenarios. This, in turn, is expected to contribute to the effective evaluation and enhancement of AV driving safety on real roads.

New emerging technology industries will be created because of the rapid development of technologies for the 4th industrial revolution and the convergence of these technologies. Government research institutes are recognized as an innovator that will lead the Fourth Industrial Revolution based on their core, fundamental, and innovative technology capabilities. Demonstration activities of Government research institutes (technology development demonstration commercialization and follow-up support) are important in order to create a virtuous cycle structure and increase technological value. Therefore, It is necessary to create a new infrastructure-based platform or demonstration research complex to support their demonstration activities. Therefore, this study explores on the cases of Sweden and the United States, which operate large-scale comprehensive test-beds, and identified key success factors such as regional bases, operating organization, partnerships and cooperative networks. We proposed benchmarks factors and strategic alternatives for construction demonstration research complex. So, this research is expected to be used as a guideline and evidence for formulating innovative cluster strategic implication and making innovation policies of research complex development for test-beds and demonstration in Saemangeum .

Use case based Software testing concerned with testing an entire system’s functionality and its constraints. User’s requirements can be drawn in form of use cases to show the internal and external behaviour of a system. The use case has been used to test software system for different levels as well as through many ways according to nature of software. Rather than proposing a new technique, it is necessary to synthesize the existing techniques of Use case based software testing which is available in the literature. A Systematic Literature Review has been performed to investigate all the current approaches of Use case based software testing techniques. A question-wise analysis has also been presented for the researchers to investigate the effectiveness of these techniques. In results, we have discussed all the existing approaches of Use case based software testing along with its strengths & weaknesses and measure the characteristics of these approaches based on some key parameters. We have concluded the current state of the art of all the existing approaches of Use case based testing. Results are based on both types of analysis; Qualitative as well as Quantitative.

Database applications play an important role in nearly every organization, yet little has been done on testing of database applications. They are becoming increasingly complex and are subject to constant change. They are often designed to be executed concurrently by many clients. Testing of database application hence is of utmost importance to avoid any future errors encountered in the application, since a single fault in database application can result in unrecoverable data loss. Many tools and frameworks for performing testing of database applications has been proposed to populate the test database and generate test cases which checks the correctness of application. They check database applications for consistency constraints and transactions concurrency. In this paper we present a DBGEN- database (test) GENerator, an automated framework for database application testing. In this framework Test Strategies for testing of embedded SQL queries within imperative language are presented. Finally we present strategies for performing efficient regression tests by reducing the resets that may occur while testing database applications. We have also computed the coverage of various test cases to predict the quality of testing. By this, we reduce the testing time and cost by approximately by 30% , thereby easing the tester to manage his testing activities easily.

To generate test cases for the unit testing of business process written in BPEL, developers have to prepare input data for the BPEL process under test (PUT) and verification conditions for output data from the PUT. It could be a tedious task due to the complexity of the PUT which describes the web flow of a distributed collaboration of individual service providers executing concurrently. This paper shows how Stream X-machine (SXM) based testing techniques could be applied to automatically generate test cases for BPEL process. The SXM describes a system as a finite set of states, an internal memory and a number of transitions between the states. One of the strengths of using a SXM to specify a system is that, under certain well defined conditions, it is possible to produce a test suite that is guaranteed to determine the correctness of the implementation under test.

Since the emergence of ChatGPT, transformer-based language models have become highly popular. This study utilizes a transformer-based approach to measure Korean sentence similarity for software testing. By doing so, we propose test cases using metamorphic relationships. The performance of the transformer models is then compared using similarity measures. First, we create a test set by transforming sentences from the Defense Daily according to specific rules. We then input these transformed sentences into the RoBERTa, Electra, and T5 models. We check whether the similarity measure between the original sentence and its variant satisfies the metamorphic relationship. The performance of each model is then compared using a similarity measure. In our experiments, the RoBERTa model satisfied metamorphic relations in MR5 and MR6, which involved transforming nouns and verbs into synonyms, and in MR7, which involved altering sentence order, with accuracy rates of 80%, 85%, and 88%, respectively. All tests passed except MR7 (77%) for the Electra model and MR1 (73%) for the T5 model. Finally, we compared the performance of each model. In the comparison, the Electra model outperformed the T5 model (99.96%) and the RoBERTa model (99.62%) with an accuracy of 99.97%.

Extracting valuable information from source code automatically was the subject of many research papers. Such information can be used for document traceability, concept or feature extraction, etc. In this paper, we used an Information Retrieval (IR) technique: Latent Semantic Indexing (LSI) for the automatic extraction of source code concepts for the purpose of test cases’ reduction. We used and updated the open source FLAT Eclipse add on to try several code stemming approaches. The goal is to check the best approach to extract code concepts that can improve the process of test cases’ selection or reduction.

This paper presents the concepts of test case based approach for the development of software systems. A variety of software development approaches are presented wherein they share some common methodology stages wherein testing plays a vital role for the success of the product. Software testing provides an objective, independent view of the software to allow the end-user to appreciate and understand the risks of software implementation. Examples of test cases for developed software have been presented.

One of the most important activities in software maintenance is Regression testing. The re-execution of all test cases during the regression testing is costly. And even though several of the code based proposed techniques address procedural programs, so many of them can’t be use directly on object-oriented programs. This paper presents modification-revealing test case selection for regression testing of object-oriented software using dependence graph model analysis of the source code. The experimental evaluation of our proposed approach was done using nine programs. We measured the performances of our selection approach using precision and inclusiveness metrics. It was observed from the results that our approach increase the efficiency and effectiveness of regression testing in term of precision and inclusiveness. It was concluded that selection of modification-revealing test cases based on affected statements provides considerably better results for precision and inclusiveness compared to retest-all and random technique, and reducing the cost of regression testing.

Regression testing remains one of the most laborious and costly software testing activities in software maintenance. Its laboriousness and costing increases with increasing number of test suits: need to changed re-testing strategy. The strategy should identify and eliminate redundant test cases in order to minimize the test cases from test suites. The aim of regression testing is to reduce the retesting effort and achieve the adequate testing coverage. An important research problem, in this context, is the new developed algorithm is needed to reduce the retesting effort, cost and time without disturbance of thoroughness. The traditional optimal page replacement algorithm is used for managing the virtual memory. Our approach has been showing that the novel optimal page replacement algorithm reducing the redundant test cases during retesting of modified object oriented program. Our testing approach is on unit level. The logic based transitive relationship model achieves the adequate testing coverage to the modified object oriented program. Hybridization of clock page replacement-counting based algorithm is used for making the logic based transition relationship model. An Illustrative example has been presented to establish the effectiveness of our methodology coupled with logic based transitive relationship model.

Generation of test cases is challenging part of software testing phase. Test cases must have ability to cover more test objective features i.e., achieve more test coverage. The different techniques for automatic generation of test cases find small set of test cases reduce human efforts as well as cost of software testing and produce most efficient and effective testing of software product. This survey gives overview of different techniques of automatic test cases generation.

In principle, structural coverage criterion enables the evaluation of test results and the automation of test execution; however, it is limited in that it cannot be applied to specification based testing. Model-Based Testing is one of the solutions used to overcome this limitation. We propose an approach in which UML activity diagrams are used as a model. Once these activity diagrams are generated from program specifications, test cases are selected systematically according to the coverage criteria identified for the activity diagrams. Applying criteria to specification-based testing is very helpful for programmers who are supposed to write tests before source codes in Agile developments. With our proposed approach, they design tests in accordance with test models rather than their intuition. In this paper, we report on an empirical study conducted in which our approach generated a more effective suite of test cases than that of the Siemens Suite.

The Unified Modeling Language (UML) is a standard notation used to model user’s requirements for object oriented software systems. With the growing adoption of UML by software developers and researchers, studies have begun to investigate how it can be used to conduct testing. Several approaches of UML-based software testing have been proposed where test cases are derived from UML diagrams based on efficient algorithms. However, these approaches still suffer from three major limitations namely; inadequate test coverage criteria, insufficient diagrams coverages and incompatibility with various UML tools. Therefore, this paper proposes an improved approach for generating test cases from various UML diagrams based on full coverage criteria. To achieve this aim, a robust method for extracting artefacts from the underlying diagrams of the software under test (SUT) was developed, where the artefacts are represented in an intermediate form using a tree and test cases are generated by traversing the contents of the tree. The proposed approach is fully automated and the generated test cases satisfied the criteria defined for the generation process. The novelty of this approach is its systematic rather than ad hoc test case generation from UML diagrams to achieve high test coverage.