건설공사 안전관리비 반영기준 개선방안 연구 : 단지개발사업을 중심으로

이영헌 경상국립대학교 융합과학기술대학원 2024 국내석사

In 2022, the number of deaths from accidents in the construction industry is 341, the highest among domestic industries, accounting for 53% of the total number of industrial accident deaths of 644. From January 2022, the Act on the Punishment of Serious Accidents, which strengthens the responsibility of business owners and managers, came into effect. Under the ?Industrial Safety and Health Act?, occupational safety and health management expenses have clear standards for appropriation, such as differentiating the application rate according to the type of construction and target amount. However, the Construction Technology Promotion Act does not specify the detailed appropriation standards for safety management expenses. This situation can bring confusion to the construction site and is directly related to safety. Therefore, this study was conducted because it was necessary to prepare a plan to improve the safety management cost standard. This study analyzes the standards for reflecting various costs related to safety management costs of LH, a representative construction company, and analyzes the current status of actual use of 50 complex development projects to study safety management cost standards improvement plans. This study analyzes the start and completion details of the completed project, the initial and current (at the time of investigation) safety management cost accounting for the LH Complex Development Corporation. The establishment of detailed standards for safety management expenses is an active response to the government's industrial safety policies, such as the Act on the Punishment of Serious Accidents. Through this study, it is believed that domestic construction safety and quality improvement can be induced.

건설공사의 안전 관련법 개선에 관한 연구

이기필 경상국립대학교 융합과학기술대학원 2024 국내석사

Looking at the recent status of accidents, the number of industrial accident deaths in Korea has been continuously decreasing from 992 in 2014 to 855 in 2020 (11% decrease), but the number of accident deaths in the construction industry has declined from 434 to 458 (5.5% increase). The construction industry accounts for more than 50% of all industrial accident deaths. The causes of construction accidents are very diverse, such as the complexity and enlargement of structures due to urban development, insolvent construction and bidding system problems due to low-cost bidding, application of new technologies and new construction methods, and inadequate systems that do not reflect construction site conditions. This study compares and analyzes the contents of the Occupational Safety and Health Act and the Construction Technology Promotion Act, which are representative laws of construction safety management, and seeks to find problems and improvement measures. The first problem is that the Occupational Safety and Health Act marks the construction industry among the entire industries in the law, paying attention to safety management of construction works, and reinforcing the safety management of construction works and supplementing the Occupational Safety and Health Act through the enactment of the Construction Technology Promotion Act. Due to the overlapping part, it takes time to understand the safety management contents of the Occupational Safety and Health Act and the Construction Technology Promotion Act. In addition, there are many foreigners in recent construction workers, which makes it difficult to understand and implement the contents of the law in Korean. Second, the departments in charge of the two laws are set up by the Ministry of Employment and Labor and the Ministry of Land, Infrastructure and Transport, respectively, which lacks efficiency. Third, the two laws have overlapping content, as each law separately stipulates similar tasks for the safety management organization and education at the construction site. Fourth, because risk assessment and safety review are separately conducted by the two laws, consistency and efficiency are insufficient. The Occupational Safety and Health Act prescribes risk assessment and confirmation before or during construction, and safety accident management. The Construction Technology Promotion Act implements a system to remove risk factors before construction by conducting safety reviews when designing construction works. Since the risk assessment and safety review conducted by the two laws are carried out by each of the two departments, feedback for safety management is difficult and consistent measures are difficult when problems arise, so it is judged that the efficiency of the results obtained by implementing the system for safety management is insufficient. Fifth, it takes a lot of time to implement the administrative procedure, as it is necessary to obtain approval of a hazard prevention plan and safety management plan with similar contents from each of the two organizations. Sixth, systematic and efficient cost execution is difficult due to the dualization of safety management costs. Occupational safety and health management costs in the Occupational Safety and Health Act are calculated by multiplying the construction cost by a certain rate according to the size of the construction, and the safety management costs in the Construction Technology Promotion Act are required to account for the cost required for safety management. The safety management costs stipulated in both laws can be sufficiently duplicated and executed, which is an obstacle to the efficient use of the budget. As an improvement plan, for effective safety management of construction works, the department in charge is unified with the Ministry of Land, Infrastructure and Transport, and the laws are integrated with the Construction Technology Promotion Act.If the accident rate and death rate are similar to the entire industry, safety management in all industrial fields It is reasonable to transfer to the Ministry of Employment and Labor, which is in charge of the job, and take charge of overall industrial safety management. Secondly, it is necessary to integrate the laws and regulations into one, and for detailed information, a plan is needed to make use of the strengths of the construction work safety management of the two laws and to compensate for the shortcomings. 1) The safety management organization follows the name and composition specified in the “Integration Guidelines for Hazard Risk Prevention and Safety Management Plan, 2007” of the Ministry of Land, Infrastructure and Transport. 2) Education is prepared by integrating the contents of the Occupational Safety and Health Act and the Construction Technology Promotion Act. 3) The administrative procedure needs a complementary system that, if the law is integrated, is reviewed by the Ministry of Employment and Labor and approved by the Ministry of Land, Infrastructure and Transport. 4) By unifying safety management costs, we establish reasonable standards for calculating safety management costs. 5) Reinforce feedback by integrating risk assessment and design safety review into one system. As for the improvement plan, it is proposed to revise the Occupational Safety and Health Act and the Construction Technology Promotion Act by referring to similar papers and cases of integration of laws. Since it is considered desirable for each committee member and department in charge to participate. The approximate adjustment bill is the improvement plan by newly establishing the safety management contents expressed in the Construction Technology Promotion Act “Chapter 5 Management of Construction Works, Section 2 Quality and Safety Management of Construction Works” as “Section 3 Safety Management of Construction Works”. Including the information presented in the section suggests a revision. I think a lot of discussion and consultation are needed for the integration of the two laws. Safety accidents in the construction industry may not be reduced if no one makes concessions and only claims my own territory. To reduce safety accidents in the construction industry, it is hoped that the improvement measures that analyze and propose the advantages and disadvantages of representative laws and regulations will be used for safety management in the construction industry. Key words: Occupational Safety and Health Act, Construction Technology Promotion Act, overlapping, legislation integration

건설공사 사전안전성 평가서 적정성 심사제도 개선 방안에 관한 연구

이태호 경상국립대학교 융합과학기술대학원 2026 국내석사

The industry that causes the most accident deaths among domestic industries is the construction industry, with an average of 392 accident deaths per year over the past five years(2020-2024). As part of the measures to prevent industrial accidents in the construction industry, the government stipulates that risk factors should be analyzed before construction work begins and a preliminary safety evaluation report reflecting countermeasures is prepared. In addition, the preliminary safety evaluation form stipulates that to prevent poor evaluation report, it must be confirmed through an appropriateness review by qualified experts or specialized institutions. On the other hand, domestic prior studies related to the preliminary safety evaluation mainly focus on writing and suggest a direction to strengthen the efficiency of the system, but studies on appropriateness reviews, which is a follow-up task after writing the preliminary safety evaluation, are insufficient. The purpose of this study is to examine whether the appropriateness review system is operating in accordance with the purpose of introducing the system and to suggest ways to improve the system, such as amendments. It is important to verify the appropriateness of the preliminary safety evaluation through fair and objective examination and to increase the degree of completion by asking the author to supplement it if any deficiencies are identified. However, as a result of examining the operation of the preliminary safety evaluation system, focusing on the representative safety laws in Korea, Occupational Safety And Health Act and Construction Technology Promotion Act, an institutional vulnerability that could lead to a so-called "self-review" in which the person who wrote the preliminary safety evaluation report and the person who reviews the appropriateness are the same. In the case of the safety management plan and the safety and health ledger, preparation agency through specialized agencies was common on behalf of the author, but it was confirmed that the person placing an order for construction works requested a specialized agency to review the appropriateness of the preparation without knowing the situation. As a result, the agency reviewed the safety management plan and the safety and health ledger prepared by the agency. Based on the results of the study, three main causes of self-review were judged, and improvement measures for each cause were presented in terms of system, orderer, and reviewer, respectively. First, in consideration of the generalization of preliminary safety evaluation agencies, related laws and regulations were proposed to prevent institutions or experts who participated in preliminary safety evaluation preparations and advice. Second, in consideration of the fact that the person placing an order for construction works is causing self-review without realizing it, a measure was proposed to establish a procedure for confirming the status of the preparation of the preliminary safety evaluation report to the designer or construction company before requesting an appropriateness review. Third, referring to Act On The Prevention Of Conflict Of Interest Related To Duties Of Public Servants, a measure was proposed to prove that the institution or expert requested to review the preliminary safety evaluation report can perform their work fairly.

공공건설의 건설사업관리 효율화 방안에 관한 연구

최재영 경상국립대학교 융합과학기술대학원 2025 국내석사

우리나라에서 건설사업관리는 1994년 성수대교 붕괴 이후 책임감리 제도를 최초로 도입하였으며, 글로벌 스탠다드에 맞춰 2014년 건설사업관리 제도로 발전되었다. 최근 연이은 부실시공 발생과 건설시장 규모 대비 건설사업관리 규모가 과도한 증가 되었고 이는 기존 건설사업관리 방식의 책임과 한계에 있어 건설사업관리에 대한 인력구조와 기술수준을 고민하게된 배경이기도 하다. 본 연구에서는 국내외 건설사업관리의 조직형태와 적용제도, 실행직무 등을 종합적 으로 분석하고 사업관리 과정의 문제점을 적시하였으며, 효율화 방안으로 미래인재 육성 17개 과제와 선진화 전략 17개 과제를 카드형태로 제안하였다. 입찰시 청년기술인에게 가점을 주고, 적정 연령의 다양한 등급 기술인 배치와 스마 트건설을 위한 건설분야 기술인정 업종의 확대, 현장에 상주하는 청년기술인에 대 한 복지지원정책을 통해 미래인재 육성방식을 상세히 제안하였으며, 또한 발주자, 감리자, 시공자 등 건설현장 참여자의 역할분담을 명확화히 하고 현장 행정사무에 대한 디지털화와 책임기술인 중심으로 현장을 운영하고 지원하는 기술 역량과 인력역량 강화를 통해 선진화가 필요하다는 결론을 도출하였다. 카드형태로 제시된 전략과 육성과제의 연구결과로서 검토배경, 문제점, 개선방향, 기대효과가 상세히 정리되어 건설산업 전반에 적용할 수 있으며, 건설사업관리용역 의 효율화와 건설산업의 발전에 핀포인트가 되기를 기대한다.

단지분야 건설정보분류체계의 BIM 활용방안

김준호 경상국립대학교 융합과학기술대학원 2025 국내석사

BIM is a digital technology that integrates and utilizes all construction information generated throughout the entire life cycle of a facility on a 3D model basis. It efficiently manages construction information generated at each stage, such as design, construction, and maintenance, minimizes errors due to information disconnection, maximizes productivity and efficiency, and improves the quality of construction projects. In particular, BIM is recognized as a new tool that organically links the creation, sharing, and utilization of construction information and supports decision-making by construction project stakeholders. In order to effectively utilize BIM in the field of land development, it is essential to build a construction information classification system that reflects the characteristics of land construction projects and the construction information requirements. This will enable consistent information generation from the planning stage of a land construction project to the final maintenance stage, support smooth communication between project stakeholders, and improve the usefulness of information, which will ultimately contribute to improving the productivity of the entire project. Therefore, this study aims to propose a construction plan for a BIM construction information classification system that takes into account the characteristics of land construction projects, and by linking it with BIM model data, present an efficient management and utilization plan for construction information throughout the entire life cycle of a land construction project. The construction information classification system proposed in this study is expected to strengthen collaboration among construction parties involved in a project and efficiently manage the various construction information generated at each construction stage, thereby maximizing the use of BIM in the construction lifecycle and further accelerating the digital transformation in the construction industry.

3기 신도시 교량 경관개선을 위한 초고강도 콘크리트(UHPC) 활용 연구

이기남 경상국립대학교 융합과학기술대학원 2024 국내석사

1. 연구 배경 3기 신도시 관련 교통, 에너지 절감, 환경 등 다양한 분야에서 특화방안이 진행 중이며 특색 있는 디자인 도시를 목표로 계획되어 있다. 그러나 3기 신도시 내·외 주요 지역을 연결하는 다수 교량 구조물의 경관에 대한 고민이 부재하다. 따라서 기존 1,2기 신도시의 교량과 차별화되고 랜드마크로써 도시경관을 특화할 수 있는 기술검토가 요구된다. 또한, 일반적으로 건설되고 있는 콘크리트 교량은 평균수명이 40~50년 수준이고 준공 후 보수·보강 및 교체공사에 투입되는 비용이 매년 발생하는 등 유지관리를 위한 개선방안이 시급한 상황이다. 이러한 문제를 해결하기 위하여 2000년 중반부터 초고강도콘크리트(Ultra High Performance Concrete)의 적용이 활발하게 이루어지고 있다. 특히 구조물의 경관개선 및 장수명화, 경량화 등 유지관리에 우수한 UHPC재료의 장점으로 인하여 지속적인 보급· 확대가 이루어지고 있다. 프랑스와 미국, 유럽, 일본 등 선진국에서는 전술한 UHPC의 장점을 교량에 접 목함으로써 구조물의 안전성 확보, 장수명화, 경량화를 실현하는 동시에 유지관리 비용을 혁신적으로 절감하고 있다. 국내에서도 UHPC 교량 기술은 현장적용 수준 까지 도달한 상태이지만 적용확대에 필요한 구체적인 현장적용 핵심기술인 내구성, 경제성, 시공성, 현장조건 및 설계지침 등의 검토가 부족하여 많은 장점에도 불구 하고 UHPC 교량이 적용된 사례는 매우 적은 실정이다. 따라서 본 연구에서는 UHPC를 3기 신도시 교량 구조물 특화에 적용함으로써 현장적용에 필요한 핵심기술을 검토하고 신도시 내 신설예정인 장경간 교량에 대 해 경관성을 향상하여 상징적인 구조물로서 도입 및 활용방안을 검토하고자 한다. - 2 - 2. 연구 목적 3기 신도시 내 교량에 일괄적인 강구조물 적용을 지양하고 선도적인 재료로서 우수한 특성이 있는 초고강도 콘크리트(UHPC)을 활용하여 경관성 개선을 위한 활 용방안 검토가 본 연구개발의 최종목표이다. 기존의 철근콘크리트 구조물은 노후화로 인해 급격한 유지보수비용이 증가하고 연간 폐기물중 50% 내외가 건설폐기물로 이를 처리하기 위한 막대한 비용뿐만 아 니라 환경보존에도 악영향을 주고 있으며 이에 따른 구조물의 수명을 획기적으로 연장하기 위한 적극적인 신소재 활용이 필요하다. 따라서, UHPC의 내구성, 경제성, 경관개선 등의 효과를 검토하여 3기 신도시 현장여건을 고려한 UHPC 교량 도입방안을 확보하는데 목표가 있다. ◦ UHPC의 재료적 특징을 분석하여 3기 신도시 교량 구조물에 경관성 향상을 위한 방안을 제시 ◦ 3기 신도시 경관개선 방안을 통해 신도시의 상징성 및 경쟁력 증대 등 공사 이미지 제고 ◦ 저형고, 미관개선, 고내구성, 장수명, 저유지비용 등 효과를 검토하여 교량 구 조물에 UHPC 적용 가이드라인 제시 ◦ UHPC 유지관리 가이드라인 제시 ◦ UHPC 교량의 기대효과 제시 교량에 UHPC를 적용함에 있어 재료적 특성과 역학적 특성의 차이가 있으므로 UHPC에 적합한 가이드라인이 적용될 필요가 있다. 따라서, 기존 교량의 한계성과 UHPC의 적용 효과를 분석하여 3기 신도시 교량 구조물 특화에 적용에 필요한 핵 심기술의 도입 및 활용방안을 검토하고자 한다. A Study on the Utilization of Ultra High Performance Concrete(UHPC) to Improve the Landscape of the 3rd New City Bridge Gi Nam, Lee Major in Safety Engineering, Graduate School of Gyeongsang National University Jinju, Korea Specialized measures are in progress in various fields such as transportation, energy conversation, and environment related to th 3 rd new city, and are planned with the goal of becoming a uniquely designed city. However, there is no concern about the landscape of the multiple bridge structures connecting the main area inside and outside the 3 rd new city. In addition, the average lifespan of concrete bridges that are generally constructed is around 40 to 50 years, and costs for repair, reinforcement and replacement are incurred every year after completion, so improvement measures for maintenance are urgently needed. To solve these problems, Ultra-High Performance Concrete has been actively applied since the mid-2000s. Inparticular, the distribution of - VI - UHPC materials is continuously expanding due to its excellent advantages in maintaining the structure, such as improving the landscape, extending lifespan, and reducing weight. Developed countries such as France, the United States, Europe, and Japan are applying the advantages of UHPC mantioned above to bridges to ensure structural safety, longer lifespan, and lighter structures, while at the same time innovatively reducing maintenance costs. In Korea, UHPC bridge technology has reached the level of field application, but due to lack of review of specific field application core technologies required for expansion of application, such as durability, economic feasibility, constructability, field conditions, and design guidelines, UHPC bridge technology has been applied despite its many advantages. The situation is very small. Therefore, in this study, we review the core technologies required for field application by applying UHPC to the specialization of bridge structures in the 3 rd new city, and review ways to introduce and utilize long-span bridges scheduled to be built in new cities as symbolic structures by improving the landscape.

노후신도시 재정비사업 추진을 위한 건설폐기물 자원화 정책 제안 방안 연구

구정원 경상국립대학교 융합과학기술대학원 2025 국내석사

For a sustainable future, we are promoting policies to prepare for resource depletion worldwide. Now, globalized RE100 is also a campaign aimed at using 100% renewable energy in preparation for resource depletion In line with this international situation, Korea is also adopting and promoting measures to reduce waste and turn it into a resource as a national policy task. The life cycle of the city is in this tone The characteristics of urban construction in Korea are that of responding to the national housing problem through large-scale urban construction It was expected to cause many problems during the reorganization process. The aging of the first new city built in the 1990s It created a national demand for urban finance from residents Accordingly, for the smooth implementation of large-scale reorganization In August 2024, a bill to reorganize the old new city is expected to accelerate urban regeneration. Accordingly, the disposal of large-scale construction waste generated by urban finance is It's believed to be a social issue Related research is lacking. So for sustainable urban renewal Efficient management of construction waste generated during refurbishment Research on how to turn it into a resource is an immediate challenge. In this study, depending on the source of waste and the process of treatment The need for an efficient management system for waste resource conversion is proposed Considering the current status of waste disposal and related systems Policy measures for proper processing and resource conversion were proposed.

기반시설내 퍼스널 모빌리티의 이용환경과 안전성 개선 방안

한승훈 경상국립대학교 융합과학기술대학원 2025 국내석사

PM(Personal Mobility) is recognized as an important alternative for the creation of smart cities and the connection of transportation systems, and the number of users has increased rapidly, centering on the younger generation, due to its advantages such as efficiency of use. The government is also revising 'the Traffic laws' and 'laws related to bicycles' use to reorganize the PM system, allowing PM to pass by bicycle paths, and supporting its use and safety. However, the number of PM-related traffic accidents and non-compliance with stability standards is increasing, and the rather negative image of using it only for a specific generation or region is emerging. As a result, the need for infrastructure and safety measures for users to use safely is also increasing. The 3rd new city aims to be a smart city and reflects the smart transportation system. In addition, in order to create a safe transportation environment for individuals and build a differentiated network, it is necessary to secure sufficient travel space for each transportation, operate pedestrian and bicycle paths, and apply them to land use plans, district unit plans, and design standards. Therefore, in this study, improvement measures were proposed through identification of standards and problem analysis for 10 infrastructures such as traffic roads, intersection crossings, entrance and exit connections, sidewalk jaw lowering, bus stops, three-dimensional intersection facilities, protected areas, parking facilities, pavement facilities, safety signs, and road markings. When planning and creating the 3rd new city in the future, it is hoped that PM will be used as a popular transportation system, away from some generations of transportation, and create a safe and convenient transportation environment in the city, comprehensively considering the network with various transportation systems and the movement efficiency of each land-use facility.

머신러닝을 활용한 콘크리트 압축강도 예측

구정모 경상국립대학교 융합과학기술대학원 2024 국내석사

Objectives : The central objective of this research is to build, implement, and evaluate a Machine Learning tool that can predict concrete compressive strength with a high degree of accuracy. Specific research goals include: · Selection and development of appropriate Machine Learning algorithms for predictive modeling. · Creation of a comprehensive and representative dataset for training and validation purposes. · Optimization of the model's hyperparameters to achieve optimal predictive performance Methods : In this study, a Machine learning model was developed using a Python program to correlate W/B ratio, Water content per unit volume or concrete, sandcoarse aggregate ratio, fly ash, superplasticizer, blast furnace slag, 7 input properties and output values of concrete compression strength, which affect concrete compressive strength. Scikit-learn, Keras, and TensorFlow open source were used to simplify the development process. And, data was preprocessed and characterized with ANN, Random Forest Regressor, LGBM, and Catboost, With grid search, the model was optimized and verified, Finally, the model verification and evaluation process were performed using the K-fold method. By training and validating the K-fold cross-validation model using 10 datasets several times, an accurate model was made possible, and a model with a small RMSE(root mean square error) was created with 20% of the evaluation data not included in the training. Conclusions : Among the Machine Learning models proposed in this study, Catboost was evaluated as a more accurate model than ANN, Random Forest Regressor, and LGBM, although large errors occurred in some predictions. Although the performance of the models based on ANN and Random Forest was low, they reached a fitting coefficient of 0.913 and 0.917 respectively, indicating a MAE(mean absolute error) value similar to that of other models. As a result, the four ensemble models for concrete compression strength prediction are sufficiently guaranteed in performance and are considered to be applicable. As there is a lot of data, it is expected that machine learning models can predict more accurately, and adding more variables such as atmospheric temperature and humidity not covered in this study can also develop models with better predictive performance.

현장조사에 기반한 공동주택 기계설비공사 안전사고 원인분석 및 저감대책 제시에 관한 연구

이창희 경상국립대학교 융합과학기술대학원 2024 국내석사

Purpose: Multi-family housing construction is the industry with the most safety accidents. Construction work consists of a comprehensive construction business and a specialized construction business. However, the overall system for safety management has mainly focused on original contractors and comprehensive construction industries. Therefore, it is necessary to find ways to prevent safety accidents for subcontractors and professional construction companies that directly employ the labor force. The purpose of this study was to identify risk factors and prepare reduction measures to prevent safety accidents. In particular, construction of housing facilities has increased in importance by constructing air conditioning, cooling, heating, and ventilation facilities for buildings, but it may be insufficient for safety management compared to electricity and fire fighting construction that is integrated and placed separately. Therefore, it focused on the construction of housing facilities Methods: As a research method, field surveys and literature surveys were conducted. The survey targets 292 stakeholders in charge of construction of housing facilities in apartment construction projects nationwide. For the survey, personal information, safety accidents, high-risk work management, and smart safety equipment were surveyed. In addition, based on domestic construction safety laws and systems and guidelines operated by actual ordering organizations, safety management deficiencies and reduction measures that may occur in construction of housing facilities were studied. Results and Discussion : The most common type of disaster in the entire construction industry and construction of housing facilities is "falling" accidents, and it is considered important to educate safety awareness and wear safety equipment to prevent safety accidents. In addition, welding work and high-altitude work of less than 2 meters should be additionally classified as high-risk work in the Safety Work Permit. Most of the smart safety equipment had no application cases, and the "closed space hazardous substance meter" would be the most effective, and the "smart safety helmet" was the most necessary to introduce. However, they responded that smart safety equipment should be reflected in the contract details such as safety management costs due to low utilization rates due to site design changes. In addition, according to the contract structure of the subcontracting method, quality deterioration and safety management problems arise due to low-cost orders, and illegal subcontracting is prevalent in the industry for separate orders. Therefore, strong management and supervision at the client and government level is needed. Construction of housing facilities should fulfill its safety management obligations, such as the preparation of safety management registers that each contractor must perform at each stage of design and construction, and it is necessary to improve awareness to ensure independent safety management. In order to derive risk factors that may occur in construction of housing facilities, the Ministry of Land, Infrastructure and Transport and LH specifications analyzed the main work contents by process and part, and compared them with the risk factor profile of the Construction Safety Management Integrated Information(CSI) to establish risk factors and reduction measures. Conclusion: In order to solve the cause of safety accidents in construction of housing facilities, it is necessary to solve various problems such as changes in systems, application of smart safety equipment, changes in industrial structure, and improvement of awareness of safety management. construction of housing facilities needs to establish a separate safety management system for construction of housing facilities itself, away from the existing safety management that is dependent on construction and leaders, and consideration and research on the prevention of safety accidents at construction sites should be continued. Key words: Construction of Housing Facilities, Apartment House, Safety Accident, Survey, Risk Factors, Reduction Measures