본 연구는 패류 독소 중 기억상실성 독성을 유발하는 domoic acid의 분석법 개선, 검증 및 분석적용성을 살펴보 았다. SAX 카트리지 정제, 검체 및 추출용매 양의 변경 과 더불어 이동상을 용매구매 조건으로 변경시킨 분석법 은 지중해담치, 홍게 그리고 멸치의 세 가지 매트릭스를 대상으로 세 농도에 대하여 식품공전법과 비교하여 유효 성을 검증하였다. 그 결과 변경된 분석법은 LOD 0.02-0.03 mg/kg, LOQ 0.05-0.09 mg/kg, 일내 및 일간 정확도 86.2- 100.4%와 일내 및 일간 정밀도 0.2-4.0%로 CODEX가이 드라인을 만족하는 우수한 분석능을 나타내었다. 특히 변 경된 시험법에서는 domoic acid와 유사한 머무름 시간을 갖는 방해물질이 검출되지 않아 위양성 결과를 방지할 수 있을 것으로 생각된다. 더 나아가 본 분석법이 국내 유통 중인 수산물을 대상으로 적용될 수 있는지 확인하고자 식 품공전의 기억상실성 패독 분석법과 함께 수산물에 적용 하여 분석하였다. 그 결과 5종의 수산물 87건 중 공전시 험법으로 분석했을 때 domoic acid가 검출된 시료는 없었 으나 변경된 분석법을 통하여 멸치 1건에 대하여 0.14 mg/ kg의 domoic acid이 미량 검출되었다. 따라서 본 연구에 서 확립된 분석법은 수산물 중 domoic acid 분석에 활용 이 가능할 것으로 보인다.
The importance of urban green space creation is increasingly recognized as the most realistic and efficient approach for fine dust mitigation in urban areas. Particularly considering the characteristics of domestic cities, the application of buffer green spaces along roads can maximize the efficiency of fine dust reduction without the need for separate green space creation. Accordingly, this study analyzed the fine dust mitigation effects based on the types of plantings in the central dividers and roadside trees in Jeonju City, Jeollabuk-do. To do this, we controlled various external variables of urban space and considered the planting arrangement types in the central dividers, carrying out the analysis using a CFD simulation. The simulation results confirmed that the central dividers with plantings demonstrated more effective ultrafine dust reduction than those without. Moreover, the arrangement of roadside trees showed a greater ultrafine dust reduction effect when adopting a multilayered structure compared to a single layer. Based on these findings, we concluded that installing both trees and shrubs simultaneously in the central dividers and along roads was effective for ultrafine dust mitigation. On this basis, we quantified the dust reduction effects of plants in urban street environments and proposed planting guidelines for roadside green spaces to improve air quality.
Recently, a closed-type plant factory has been receiving attention as a advanced agricultural method. It has diverse advantages such as climate-independence, high productivity and stable year-round production. However, high energy cost caused by environmental control system is considered as a challenges of a closed-type plant factory. In order to reduce the energy cost, investigation about energy load which is directly connected to energy consumption needs to be conducted. In this study, energy load changes of a plant factory have been analytically analyzed according to the environmental changes. The target plant factory was a lettuce growing container farm. Firstly, the impact of photoperiod, set temperature and relative humidity change were examined. Under the climate condition of Daejeon in South Korea, increase of photoperiod and set temperature rose a yearly energy demand of a container farm. However, increase of set relative humidity decreased a yearly energy demand. Secondly, the climate environment effect was compared by investigating the energy demand under 9 different climate conditions. As a result, the difference between maximum and minimum value of the yearly energy demand showed 21.7%. Lastly, sensitivity analysis of each parameter (photoperiod, set temperature and relative humidity) has been suggested under 3 different climate conditions. The ratio of heating and cooling demand was varied depending on the climate, so the effect of each parameter became different.
In light of recent social concerns related to issues such as water supply pipe deterioration leading to problems like leaks and degraded water quality, the significance of maintenance efforts to enhance water source quality and ensure a stable water supply has grown substantially. In this study, scan statistic was applied to analyze water quality complaints and water leakage accidents from 2015 to 2021 to present a reasonable method to identify areas requiring improvement in water management. SaTScan, a spatio-temporal statistical analysis program, and ArcGIS were used for spatial information analysis, and clusters with high relative risk (RR) were determined using the maximum log-likelihood ratio, relative risk, and Monte Carlo hypothesis test for I city, the target area. Specifically, in the case of water quality complaints, the analysis results were compared by distinguishing cases occurring before and after the onset of "red water." The period between 2015 and 2019 revealed that preceding the occurrence of red water, the leak cluster at location L2 posed a significantly higher risk (RR: 2.45) than other regions. As for water quality complaints, cluster C2 exhibited a notably elevated RR (RR: 2.21) and appeared concentrated in areas D and S, respectively. On the other hand, post-red water incidents of water quality complaints were predominantly concentrated in area S. The analysis found that the locations of complaint clusters were similar to those of red water incidents. Of these, cluster C7 exhibited a substantial RR of 4.58, signifying more than a twofold increase compared to pre-incident levels. A kernel density map analysis was performed using GIS to identify priority areas for waterworks management based on the central location of clusters and complaint cluster RR data.
PURPOSES : This study aims to analyze the causes of pedestrian traffic accidents on community roads. METHODS : This study collected variables affecting pedestrian traffic accidents on community roads based on field surveys and analyzed them using negative binomial regression and zero-inflated negative binomial regression models. RESULTS : Model analysis results showed that the negative binomial regression model is more suitable than the zero-inflation negative binomial regression model. Additionally, the segment length (m), pedestrian volume (persons/15 min), traffic volume (numbers/15 min.), the extent of illegal parking, pedestrian-vehicle conflict ratio, and one-way traffic (one: residential, two: commercial) were found to influence pedestrian traffic accidents on community roads. Model fitness indicators, comparing actual values with predicted values, showed an MPB of 1.54, MAD of 2.57, and RMSE of 7.03. CONCLUSIONS : This study quantified the factors contributing to pedestrian traffic accidents on community roads by considering both static and dynamic elements. Instead of uniformly implementing measures, such as pedestrian priority zones and facility improvements on community roads, developing diverse strategies that consider various dynamic factors should be considered.
PURPOSES : Traffic volume, an important basic data in the field of road traffic, is collected from traffic survey equipment installed at certain locations, which sometimes results in missing traffic volume data and abnormal detection. Therefore, this study presents various missing correction techniques using traffic characteristic analysis to obtain accurate traffic volume statistics. METHODS : The fundamental premise behind the development of a traffic volume correction and prediction model is to set the corrected data as the reference value, and the traffic volume correction and prediction process for the outliers and missing values in the raw data were performed based on the set values. RESULTS : The simulation results confirmed that the algorithm combining seasonal composition, quantile AD, and aggregation techniques showed a detection performance of more than 91% compared with actual values. CONCLUSIONS : Raw data collected due to difficulties faced by traffic survey equipment will result in missing traffic volume data and abnormal detection. If these abnormal data are used without appropriate corrections, it is difficult to accurately predict traffic demand. Therefore, it is necessary to improve the accuracy of demand prediction through characteristic analysis and the correction of missing data or outliers in the traffic data.
본 연구의 목적은 청소년의 진로적응력의 잠재프로파일 유형과 사회적 지지인 양육태도, 친구관계, 교사관계의 영향력을 확인하는 것이다. 연구 대상자는 한국청소년정책연구원에서 실시한 「한국아동·청소년패널조사 2018 (KCYPS 2018)」에서 중1코호트의 제4차 조사(2021년)에 해당하는 고등 학생 1학년 응답자 2,265명을 최종 연구 대상자로 선정하였다. 진로적응 력의 잠재프로파일 분류와 예측 변인들의 영향력을 확인하기 위해서 SPSS 26.0과 JAMOVI 2.2.5를 활용하여 잠재프로파일분석과 다항로지스 틱회귀분석을 수행하였다. 연구결과에서는 ‘진로적응 매우미흡집단’, ‘진 로적응 미흡집단’, ‘진로적응 보통집단’, ‘진로적응 우수집단’ 총 4개의 잠재프로파일 집단으로 분류되었다. 또한, 양육태도와 교사관계는 모두 잠재프로파일 분류에 유의한 영향을 미치는 것으로 나타났다. 그러나, 친 구관계는 잠재프로파일 분류에 유의한 영향을 주지 않는 것으로 확인되 었다. 이러한 연구결과는 향후, 청소년들의 진로적응력을 강화할 수 있는 교육제도 수립 및 프로그램 개발에 도움이 될 수 있을 것이다.
PURPOSES : This study aims to examine actual cases of providing detour information in accidental situations such as traffic accidents and road construction through a VMS installed on national highways in metropolitan areas with alternative routes, as well as cases of simultaneously providing travel time information on parallel paths such as national and regular highways. For each case, we analyzed whether the provision of VMS traffic information leads to route changes and substantial effects. METHODS : To analyze traffic changes on the main and detour roads based on the detour information provided on traffic accidents in actual cases, the traffic volume and speed on the accident day were compared with those on the same days and at the same time of the day (regular days) based on the VDS data of the main and detour roads. Cases providing more detour information on road construction were investigated by examining three time periods: one week from construction initiation and one week before and after the construction period (regular days). The traffic volume and speed on the main road were compared based on the VDS data, and those on the detour road were compared based on data made available by private entities. Regarding the cases of simultaneously providing drivers with comparative information on travel time over parallel sections of national and regular highways, traffic situation changes in highways were analyzed in the following special traffic control periods (New Year's Day, NY Day), during which congestion is expected due to heavy traffic: before and after the provision of comparative information for 2015 New Year's Day and 2016 NY Day. RESULTS : The detour rate related to route changes based on the detour information for traffic accidents was 35%. On the detour route, the traffic volume increases as traffic from the main road is absorbed. However, the average travel speeds did not differ significantly. When further detour information regarding a road construction project was provided, the detour rate from the main road was 21%. The travel speeds were similar, except on the first day of construction. Almost no changes were observed in the first section of the detour. The speed slightly decreased in the second section but did not significantly hinder the traffic flow. When comparative traffic time information on parallel routes (national highways and expressways) was provided, the traffic volume increased to some extent after the report was provided for every case. However, the data frequency rate in the 5-min unit, which was still under the congestion speed standard (40 km/h), decreased. This indicates that traffic congestion was significantly relieved. CONCLUSIONS : Previous studies on detour rates or route changes based on VMS traffic information have focused on VMS instruments on expressways. Although their estimates were based on simulated situations, this study used actual VMS installed on national highways. In addition, this study utilizes the existing case records of national highway ITS centers, covering traffic situation monitoring, measures for accidental situations, etc., in regular times or special traffic control periods, as well as statistical data, including ITS real-time traffic information. The analysis results of this study accurately represent situations on actual roads and can be utilized to analyze future ITS operation and installation project effects.
PURPOSES : This study investigates the factors affecting extra-long tunnel accidents by integrating data on tunnel geometry, traffic flow, and traffic accidents and derives the underlying implications to mitigate the severity of accidents. METHODS : Two processes centered on three key data points (tunnel geometry, traffic flow, and traffic accidents) were used in this study. The first is to analyze the spatial characteristics of extra-long tunnel traffic accidents and categorize them from multiple perspectives. The other was to investigate the factors affecting extra-long tunnel traffic accidents using the equivalent property-damage-only (EPDO) of individual accidents and the aforementioned data as the dependent and independent variables, respectively, by employing an ordered logistic regression model. RESULTS : Gyeonggi-do, Gyeongsangnam-do, and Gangwon-do are three metropolitan municipalities that have a significant number of extra-long tunnel accidents; Busan and Seoul have the most extra-long tunnel accidents, accounting for 23.2% (422 accidents) and 18.6% (339 accidents) of the 1,821 accidents that occurred from 2007 to 2020, respectively. In addition, approximately 70% of extra-long tunnel traffic accidents occurred along tunnels with lengths of less than 2 km, and Seoul and Busan accounted for over 60% of the top 20 extra-long tunnels with accidents. Most importantly, the Hwangryeong (down) tunnel in Busan experienced the most extra-long tunnel traffic accidents, with 77 accidents occurring during the same period. As a result of the ordered logistic regression modeling with EPDO and multiple independent variables, the significant factors affecting the severity of extra-long tunnel traffic accidents were determined to be road type (freeway, local route, and metropolitan city road), traffic flow (speed), accident time (year, summer, weekend, and afternoon), accident type (rear end), traffic law violations (safe distance violation and center line violation), and offending vehicles (van, sedan, and truck). CONCLUSIONS : Based on these results, the following measures and implications for mitigating the severity of extra-long tunnel traffic accidents must be considered: upgrading the emergency response level of all road types to that of freeways and actively promoting techniques for regulating high-speed vehicles approaching and traversing within extra-long tunnels are necessary. In addition, the emergency response and preparation system should be reinforced, particularly when the damage from extra-long tunnel traffic accidents is more serious, such as during the summer, weekends, and afternoons. Finally, traffic law violations such as safe distance and centerline violations in extra-long tunnels should be prohibited.
PURPOSES : To prevent an increasing number of drowsiness-related accidents, considering driver fatigue is necessary, which is the main cause of drowsiness accidents. The purpose of this study is to propose a methodology for selecting drowsiness hotspots using continuous driving time, a variable that quantifies driver fatigue. METHODS : An analysis was conducted by dividing driver fatigue, which changes according to time and space, into temporal and spatiotemporal scenarios. The analysis technique derived four evaluation indicators (precision, recall, accuracy, and F1 score) using a random forest classification model that is effective for processing large amounts of data. RESULTS : Both the temporal and spatiotemporal scenarios performed better in models that reflected the characteristics of road sections with changes in time and space. Comparing the two scenarios, it was found that the spatiotemporal scenario showed a difference in precision of approximately 10% compared with the temporal scenarios. In addition, [Model 2-2] of the spatiotemporal scenario showed the best predictive power by assessing the model’s accuracy via a comparison of (1-recall) and precision. This shows better performance in predicting drowsy accidents by considering changes in time and space together rather than constructing only temporal changes. CONCLUSIONS : To classify hotspots of drowsiness, spatiotemporal factors must be considered. However, it is possible to develop a methodology with better performance if data on individuals driving vehicles can be collected.
본 연구는 크리스천 아동, 부모, 교사의 리더십에 관한 국내 연구동향을 살펴 봄으로써 향후 크리스천 아동, 부모, 교사의 리더십 연구의 발전 방향을 제시하 는데 연구의 목적이 있다. 연구의 객관성과 타당성의 확보를 위해 공동연구자 이외에 크리스천 리더십 전문가 3인을 포함하여 5인으로 평정 집단을 구성했으 며 평정 절차를 거쳐 총 36편의 분석 대상 논문을 선정했다. 크리스천 아동의 리더십 연구는 주로 섬김의 리더십을 주제로 청소년을 대상 으로 한 연구가 많이 수행되었고, 다양한 연구방법 접근 시도가 있었다. 크리스 천 부모의 리더십 연구는 대부분 부모 교육 연구에서 이뤄졌으며, 프로그램 개 발 연구는 소수의 연구에 그쳤다. 크리스천 교사의 리더십 연구는 다른 리더십 연구에 비해 많은 비중을 차지했으나 대부분 섬김의 리더십과 변혁적 리더십으 로 제한적이었으며, 이론적 탐색 연구에 그쳤다. 향후 크리스천 아동, 부모, 교사의 리더십에 관한 연구를 위한 제언은 3가지로 요약된다. 첫째, 이론적 측면에서 크리스천 아동, 부모, 교사의 리더십에 관한 연 구의 학문적 체계화를 위한 이론 구축이 필요하다. 둘째, 방법론적 측면에서 크리 스천 아동, 부모, 교사의 리더십에 관한 프로그램 및 척도개발이 수행 되어야하며 질적연구를 통한 다각도의 접근이 필요하다. 셋째, 실천적 측면에서 크리스천 아 동, 부모, 교사의 리더십 개발 및 확장, 보급을 위한 코칭 접근을 제언한다.
PURPOSES : In this study, energy-consuming processes in asphalt plants were evaluated, and the drying and mixing processes were characterized using a thermal equilibrium equation-based model to quantitatively estimate the amount of energy consumed during the production of mixtures in asphalt concrete plants. METHODS : An energy consumption model based on the thermal equilibrium equation was used to estimate the energy consumption of the aggregate drying process that consumes the maximum energy; the energy consumed for material transportation, storage, and operation of other facilities was cited from the literature. The results were compared with the actual results obtained for recycled hot asphalt mixtures and recycled warm mix asphalt mixtures, and a sensitivity analysis was performed by varying the conditions. RESULTS : An analysis of the main processes required to produce asphalt mixtures showed that the water content had the largest impact on energy consumption (approximately 80%). This quantitatively supports the opinion of field practitioners that maximum energy is consumed during aggregate drying. Although some discrepancies were observed, the results were found to be reasonable and within the range of typical measurements. CONCLUSIONS : The thermal energy consumption estimation model provides consistent results that reflect the characteristics of the mixture and can be used to derive the thermal energy consumption rates for individual materials, such as aggregates and binders. This can be used to identify the priorities for process optimization within a plant.
PURPOSES : The purpose of this study was to evaluate the common performance of asphalt pavements, determine the timing of preventive maintenance, and determine the optimal timing of application of the preventive maintenance methods by analyzing PMS data. METHODS : Using PMS data on asphalt pavement performance on highways, we derived the major damage factors and evaluated them according to the public period and traffic level. Among the factors evaluated, we determined those that could be improved by preventive maintenance, calculated the amount of change annually, and derived the timing of the application of the preventive maintenance method through correlation analysis. RESULTS : Among highway PMS data factors, crack variation was found to affect preventive maintenance, which increased rapidly after five years of performance. Traffic analysis showed that changes increased rapidly in the fifth, sixth, and seventh years when AADT exceeded 20,000, exceeded 10,000, and was under 10,000, respectively. Analysis of the amount of crack variation according to the pavement type showed that crack variation increased rapidly in the overlay section compared to the general AP section. CONCLUSIONS : Crack variation is the performance factor that was expected to be effective in preventive maintenance, and the PMS data showed that the initial application time of the preventive maintenance method varied by one year, depending on the traffic volume.
본 연구는 영화 <헤어질 결심>을 중심으로 영화 속 색상의 상징적 의 미와 감독의 제작 스타일을 탐구하여 영화 속에서 색상이 얼마나 중요한 지를 이해하고, 감독이 색상을 통해 주제를 어떻게 전달하는지를 보여주 고자 한다. 본 연구는 움베르토 에코 기호학을 바탕으로 색상의 보편적 인 상징성과 결합하여 ‘표현-내용-해석체’의 삼원론적 기호 관계를 분석 방법으로 사용하고, 추측 방법을 통해 색상 기호 의미의 생산 과정을 설 명하고 영화 속 색상의 다양한 표현 방식이 상징하는 의미를 심도 있게 발굴하였다. 또한, ‘기호 활동’의 반복 이론을 통해 서로 다른 색상의 반 복적인 등장을 분석하여 색상과 영화 주제와의 연관성을 설명하였다. 본 연구를 통해 박찬욱 감독이 독창적인 색상 활용을 영화의 디테일한 부분 과 잘 접목시켜 영화 표현 형식의 다양화와 주제 강화를 실현하고, 관객 의 감성적 참여를 높인다는 것을 알 수 있다. 색상은 긴장감이 넘치는 분위기를 조성할 뿐만 아니라 인물에게 신비한 매력을 부여해 전반적인 스토리에 예술적 요소를 더한다. 본 연구는 영화 속 색상 활용에 따른 기호학 분석에 새로운 아이디어와 방법을 제시하고, 영화 제작에 이론적 인 참고 자료를 제공하고자 한다. 향후 연구에서는 더 많은 기호학 이론 을 활용해 연구 범위를 확대하고, 영화 색상 활용에 대한 인식을 풍부하 게 하여 영화 예술 발전을 더욱 촉진할 수 있을 것이다.
본 연구는 보육교사가 지각하는 직무만족, 교육신념, 조직몰입, 역할수행에 대한 인식을 바탕으로 직업적합도와 근무 기관유형에 따른 차이를 알아보고, 주요변수들 간의 구조적 관계를 분석하는 것을 목적으로 하였다. 이를 통해 보육교사 가 자신의 역할수행을 원활하게 수행함으로써 영·유아교육기관이 교육서비스의 질을 향상시킬 수 있는 방안을 모색해보 고자 하였다. 이를 위해 보육교사 339명을 대상으로 설문조사를 실시하였으며, IBM SPSS Statistics 26.0과 AMOS 26.0 프로그램을 활용하여 수집된 자료를 분석하였다. 본 연구의 주요 결과는 다음과 같다. 첫째, 보육교사가 지각하는 직무만 족, 교육신념, 조직몰입의 수준은 보통이었고, 역할수행은 보통 이상으로 나타났다. 둘째, 보육교사는 직업적합도가 높을 수록 직무만족, 교육신념, 조직몰입, 역할수행에 대한 인식이 높았고, 보육교사가 국·공립어린이집에 근무하는 경우, 민간 어린이집 또는 가정어린이집에 근무하는 보육교사보다 직무만족, 조직몰입(정서적몰입), 역할수행에 대한 인식이 높았다. 셋째, 보육교사의 직무만족은 교육신념과 조직몰입에, 교육신념은 역할수행에 정(+)적인 영향을 미치는 반면, 직무만족과 조직몰입은 역할수행에, 교육신념은 조직몰입에 유의한 영향을 미치지 않는 것으로 나타났다. 넷째, 보육교사의 직무만 족이 역할수행에 미치는 영향에서 교육신념은 매개효과가 존재하나, 조직몰입은 매개효과가 유의하지 않은 것으로 나타 났다. 영·유아교육기관의 교육서비스 질을 향상시키기 위해서는 보육교사의 근무환경이 국·공립어린이집 수준으로 개선 되어야 하고, 이를 통해 보육교사의 직무만족과 조직몰입의 수준을 높이는 방안이 마련되어야 하며, 보육교사의 교육신 념을 제고시키기 위한 교육이 필요하다.
This study was conducted to examine the architectural characteristics of Hak-seong Lee Family's Geun-jae-gong Historic House located in Seok-cheon-ri, Ung-chon-myeon, Ulju-gun, Ulsan. The house is said to have been rebuilt in the early 20th century after it was built in the 18th century, and now there are nine buildings left, including the An-chae, Sa-rang-chae, Sa-dang, storehouses and etc. This house is a large-scale house that is difficult to find similar cases in near region. The division of areas on each building is clear, and it is evaluated that it retains the typical characteristics of the head family in the late Joseon Dynasty in terms of its overall size and layout. In addition, the current wooden structure, which is said to have been rebuilt in the early 20th century, shows the composition method and space utilization method of the 3-Dori type upper structure, which have become more diverse since the late Joseon Dynasty. This has not been dealt with in the previous survey, and should be considered in detail through this paper.
산업과 기술의 발전으로 인해 수계로의 화학물질 배출이 증가하고, 이로 인해 환경오염과 인체 건강에 부정적인 영향을 미치 는 위험이 더욱 증가하였다. 따라서, 수질을 종합적으로 평가할 수 있는 생태독성평가의 중요성이 강조되고 있다. 본 연구에서는 렌즈프 리 그림자 이미징 기술을 활용한 Cellytics 플랫폼을 소개하며, 화학물질에 의한 로티퍼(Brachionus plicatilis)와 미세조류(Dunaliella tertiolecta) 의 생물학적 변화를 신속하게 측정하고 독성을 분석하는 기법을 제안한다. 이를 위해 로티퍼와 미세조류를 톨루엔에 각각 1분과 5분 동 안 노출한 뒤, Cellytics를 이용하여 로티퍼의 이동성과 미세조류의 형태 변화를 측정하여 독성을 평가하였다. 로티퍼의 이동성과 미세조류 의 형태변화는 모두 110.4 mg/L의 농도에서 대조군과 유의미한 차이를 나타내며(p<0.05), 이는 로티퍼의 생존율로 분석한 톨루엔의 LC50(552 mg/L)보다 낮은 농도였다. 본 연구에 따르면, 로티퍼와 미세조류를 전통적인 방식으로 최소 수 일 간 배양하여 얻을 수 있는 생 태독성평가 결과를 매우 짧은 시간(5분 이내)에 분석하고, 두 생물의 독성평가 결과를 신속하게 제공하여 현장에서 활용 가능한 신뢰성 높은 정보를 제공할 수 있음을 보여준다. 이는 독성평가를 이용하는 다양한 연구의 활용에 기여할 수 있으며, 환경보호 및 인체 건강 관 련 정책 수립에 도움이 될 것으로 기대된다.
용인 영문리유적 출토 편주형 석도 5점에 대한 사용흔을 분석하여 그 사용 방식을 추정하였다. 분 석 결과 아래쪽 날에 대해서는 기존의 사용 방식을 다시 한 번 입증하게 되었다. 구체적인 사용법은 오른손 중지에 끈을 연결하여 석도를 잡은 다음, 엄지로 벼과식물을 석도에 밀착시키고 검지로 누르 면서 손목을 비틀어 이삭을 따는 형태로 복원되었다. 측면 날에 대한 분석에서는 날을 따라 분포하는 발달된 벼과식물 접촉 광택, 날과 같은 방향의 선상흔 등이 관찰되어, 수확 후 짚 확보나 잡초 제거를 위해 날과 평행하는 방향으로 석도를 움직여 여러 줄기의 벼과식물을 한 번에 자르는 용도가 상정되 었다. 또한 앞뒷면 광택 발달 정도의 차이에 따라 오른손잡이와 왼손잡이의 사용을 구분할 수 있었으 며, 구체적인 사용법으로 직접 석도를 손에 잡고 다른 손으로 벼과식물의 윗부분을 잡은 다음 작업자 의 몸 쪽으로 석도를 당기면서 절단하는 방식이 추정되었다. 그리고 이러한 분석을 통해 편주형 석도 가 수확 현장에서 이루어지는 두 가지의 다른 작업에 대응 가능한 다목적 도구임을 확인할 수 있었다.
Recently, the market competition has been fiercer due to the acceleration of technological change and the launch of intelligent products. In this situation, technology cooperation activities through networks rather than independent technological innovation activities of a single company or institution are recognized as a crucial strategy to gain competitiveness. Technology cooperation can take various forms depending on the target technology, and researchers have conducted performance analyses of technology cooperation types. However, there have not been data-based quantitative studies on the types and trends of technology cooperation for the target technology. In this paper, we explored the difference between the technology cooperation types by technology and time using the formal concept analysis method and co-patent information. In particular, the proposed methodology has been verified through the case study of electric vehicles, and it is intended to suggest the direction of technological cooperation according to specific technologies and cooperation targets in the future
Recently, the government has provided support such as entering new markets, expanding sales channels, and supporting manpower, not just in the form of funding, to efficiently and effectively support limited national resources to improve corporate performance. In this study, we tried to find out the effect of government support for companies that have benefited from the Excellent Technology Research Center Project (ATC Project) and the World Class 300 project using propensity score matching. As a result of the analysis, the effect of government support for the ATC project became visible after the appointment period, while the effect of the World Class 300 project was insignificant. This means that when the size of the company is small, the effect of government support is more pronounced. This suggests that in order to maximize the effectiveness of government support, appropriate national policy interventions such as government innovation funding are needed when the size of the company is small. In this study, differences in the timing, performance indicators, and company size of policy support effects were found in the growth stage of a company from a mid- to long-term time series perspective, suggesting that support policies based on this need to be adjusted and redesigned.