The repeated use of biocidal products, including household insecticides and disinfectants, has led people to seek safer alternatives, such as light traps, ultrasound generators, or repellent lamps. By appearances, these physical/non-chemical alternatives seem appealing to many consumers and are gaining more attention. However, unlike biocidal products, these alternatives are not subject to mandatory approval and registration processes, and no standards for efficacy and safety are in place. Given the increasing numbers of insect traps on the market, there is an urgent need to investigate their efficacy. In the present study, we examined the attraction activity of ten commercially available insect trap products. They varied in size, structure, trapping methods (fan or sticky pad), and attractants. Their efficacies were assessed under both laboratory condition (1.8m x 1.8m x 1.8m) and semi-field room condition (4m x 6m x 2m). Ul*****APTM demonstrated the highest capture rate (%), leading us to further study the role of its attractant. Notably, the capture rate increased by 28.9% when the CO2 attractant was used, displaying statistical differences (P = 0.032). For practical application in the field, consumer acceptance and satisfaction were monitored using 20 participants. The potential of insect traps as viable alternatives to biocidal products is discussed.

In Vietnam, reclaimed asphalt pavement technology is considered as the key to reduce the cost of pavement construction, and decrease the industrial waste from flexible pavement rehabilitation. Ministry of Transportation has concentrated to develop RAP technology since 2008. As a result, there are three trademark of recycling technologies applied in Vietnam such as Wirtgen (Germany), Hall Brothers (U.S.), and Sakai (Japan). This paper is focused on asphalt pavement investigation of field and laboratory tests from Cold In-place recycling technology. The laboratory tests carried out on the material were conventional tests including Marshall stability, indirect tensile strength... Field data was collected using a Benkelman beam and core specimens for indirect tensile strength test.

It has been recognized that the performance of pavements is closely related to the properties of the underlying unbound layers and subgrade. It has also been recognized that unbound pavement materials possess a complex nature and often exhibit nonlinear behaviors [1, 2]. The Mechanistic-Empirical Pavement Design Guide (MEPDG) is founded on the use of resilient modulus as the primary input parameter when characterizing unbound pavement materials [3, 4]. The resilient moduli of unbound materials are typically determined by performing repeated load triaxial (RLT) tests in the laboratory. Due to that laboratory resilient modulus tests require sophisticated equipment and trained operators following complicated test procedures, many transportation agencies may not have access to the laboratory facility and opt to correlate resilient modulus with field tests [5]. The long-term pavement performance (LTPP) program offers a large and diverse database that includes a range of laboratory-derived and field-derived properties for unbound materials of many in-service pavement sections. This study is aimed to utilize LTPP data to develop a correlation between the laboratory-derived resilient modulus and a field-derived parameter, dynamic cone penetration index (DCPI) for unbound aggregate materials. Data extracted from the LTPP database were subjected to a thorough quality check to ensure that the data are of good quality and without errors. One-on-one univariate regression was first performed to examine the significance of different variables, including DCPI and some physical properties such as dry unit weight, water content, plasticity index, percent passing No.200 sieve. The physical properties that show strong correlation were selected to be combined with field test parameter (DCPI) to conduct a multivariate regression analysis. A statistical model was developed for the prediction of resilient modulus of unbound aggregates from the DCP test parameters and physical properties. The model predicted a separate data set that did not participate in the correlation analysis, suggesting the success of applying the DCP test in evaluating the resilient modulus of pavement unbound aggregate materials.

The hawthorn spider mite, Amphitetranychus viennensis (Zacher), is an important tetranychid causing damage on fruittrees and woody ornamental plants. We investigated the effect of a mycoinsecticide BotaniGard® ES at different humiditylevels on the eggs and adults mortality of A. viennensis. In a laboratory condition, egg mortality was significantly influencedby the conidial concentration and RHs. Highest mortality of eggs was observed at 1×108 conidia/ml with 95% RH thanother conditions. In 1×108 conidia/ml, LT50 at 95 and 75% RH were significantly different from 55% RH. In BotaniGard®spray in cherry plants, mites decreased on day 6 at all the concentrations, but the mite populations rebounded exceptin 1×109 conidia/ml where it maintained 0 until 9 days after spraying. It is therefore concluded that B. bassiana hasa potential to be used against A. viennensis

OBJECTIVES : Visibility at night can be improved by using retroreflection for short distances and phosphorescent line markings for long distances. In this study, we analyzed the characteristics of the phosphorescent line marking through a laboratory luminance test. Field performance analysis was performed through tests conducted on the road. We also examined the luminance measurement methods using the digital image obtained during the phosphorescent visibility evaluation. METHODS : In this study, the laboratory luminance test of the phosphorescent line marking was conducted using seven specimens to characterize the luminance changes according to the type of the glass beads, the thickness of the phosphorescent line marking, and the brightness and irradiation time of the light source. Phosphorescent and general line markings were made at 150 m to investigate the field luminance performance. A preliminary review of the luminance measurement methods was made using a digital image from a digital singlelens reflex (DSLR) camera. The measured luminance ratio of the general and the phosphorescent line markings was compared with the calculated luminance ratio using luminance analysis. RESULTS: Through the laboratory luminance test, it was seen that the change in luminance, which corresponds to the brightness of the light source, appears large but the influence of the thickness and irradiation time is low. The field performance test of the phosphorescent line marking conducted on the road involved measuring the luminance on the day the marking was made and 7 days after the marking was made. The luminance was found to be 190 mcd/m2 at 30 min after sunset and approximately 10-12 mcd/m2 4h after sunset. The results of the luminance test were captured using a digital image for each time group. The luminance ratio of the phosphorescent line marking, when compared to that of the general line marking, showed a similar trend within a 13% maximum error. Additionally, when this luminance ratio is compared to the direct field measurement, it could be confirmed that the luminance ratio, as captured in the digital image, showed a similar tendency. CONCLUSIONS : 1) The change in luminance corresponding to the brightness of the light source is significant in comparison with that corresponding to the thickness and the irradiation time. In addition, the results of the field test for the phosphorescent line marking satisfied the phosphorescent fire protection standard. 2) We examined the validity of the luminance measurement method using a digital image and we concluded that the change in the luminance ratio shows a similar tendency in both the cases. The results can form the basis for luminance measurement methodology for the construction and maintenance of phosphorescent line markings.

PURPOSES: The purpose of this study is to suggest a specific investigation guideline to decide priority of repairing old concrete pavements that pile up substantially. METHODS : In this study, a principle of division of homogeneous sections was proposed to reflect the characteristics of the pavement reasonably in the specific investigation results. In addition, a checklist and guideline of field investigation were suggested for the old concrete pavement sections, which require inspection toward their durability and structural performance. Furthermore, the items of laboratory test necessary to the old concrete pavement were suggested based on the existing laboratory test considering characteristics of the old concrete pavement. The present condition of the old concrete pavement could be analyzed by the test results. RESULTS: A method of division of homogeneous sections suitable for the specific investigation of the old concrete pavement was suggested. The proportions of distress severity of pavement sections were compared by distress type to figure out the present state of the old concrete pavement. Scaling, durability cracking (or alkali-silica reaction), and longitudinal spalling were selected as the most severe distress types. The detailed positions of the sections were also suggested. The checklist of the specific investigation was categorized by field survey and laboratory test, and its evaluation criteria were proposed. The three types of the sections of durability cracking (or alkali-silica reaction), bridge connection, and asphalt overlay were selected as the sections of the field survey. The compressive strength, void structure, and chloride penetration depth were suggested as the items of the laboratory test. CONCLUSIONS : A fundamental level of the guideline was suggested in this study to resolve the problem of old concrete pavement. Appropriate guidelines related to the repair of the old concrete pavement should be provided by performing additional research efforts.

PURPOSES : The purpose of this study is to evaluate of field application and laboratory performance of warm-mix asphalt (WMA) according to the dosage rate of organic-based WMA additive. METHODS: Three asphalt mixtures, i.e., hot mix asphalt (HMA), WMA with the dosage rate of 1.5%, WMA with the dosage rate of 1.0%, were sampled from the asphalt plant when the field trial project were constructed. With these mixtures, the laboratory testings were performed to evaluate the linear viscoelastic characteristics and the resistance to moisture, rutting and fatigue damage. RESULTS : From the laboratory test results, it was found that the WMA with the reduced dosage rate of additive would be comparable to HMA and WMA with the original dosage rate in terms of the dynamic modulus, tensile strength ratio, rutting resistance. However, the fatigue reisistance of WMA with the reduced dosage rate was slightly worse but it should be noted that the fatigue performance is necessarily predicted by combining the material properties and pavement structure. CONCLUSIONS: Through the field construction and laboratory testings, the dosage rate of organic-based WMA additive could be reduced from 1.5% to 1.0% without the significant decrease of compactability and laboratory performance. The long-term performance of the constructed pavement will be periodically monitored to support the findings from this study.

본 연구에서는 낙동강 진우도 해빈에 모래 포집시험구(실험 Site)를 설치하고 자연해빈에서의 비사 계측, 광파측거의를 통해 대표 해빈단면의 변화를 관찰하여 서로 비교분석하였다. 또한 해빈에서 바람에 의해 공급되는 모래(비사)의 해안 법선방향 및 평행한 방향의 모래 공급량을 정량적으로 평가하고자 하였다. 또한 실내에서의 풍동실험장치를 이용하여 해빈상에 초기 성장조건에 해당하는 식생의 이식하여 바람에 의해 이송되는 비사의 포집특성을 관찰하였다.

PURPOSES : This study evaluated the field applicability and laboratory performance of warm-mix asphalt (WMA) as an alternative technology in asphalt pavement. METHODS : The pilot road using two different types of WMA mixture and one HMA mixture was constructed in Waegwan-Seokjeok road construction site and the mixtures were sampled at the asphalt plant for laboratory testings. The field applicability was assessed in environmental aspects, such as CO2 emission, and in aspects of constructibility using the existing equipment and procedure, i.e., thickness and density measurement. The laboratory testings included the moisture susceptibility test by AASHTO T283, dynamic modulus test, triaxial repeated load permanent deformation test, and the fatigue test. RESULTS : The temperatures for production and compaction of WMA were 20~30℃ lower than those for HMA and therefore, the noxious gas emission were significantly reduced. The field density of WMA pavements was similar or better than that of HMA pavement. From the laboratory testings, it was found that WMA mixtures exhibit comparable performance to HMA mixture in moisture susceptibility, permanent deformation, and fatigue performance. CONCLUSIONS : With these results, it would be concluded that WMA could replace the existing HMA technology without any significant issue. To support this conclusion, it is necessary to track the long-term performance of WMA in pilot road.

본 연구에서는 도심지 열섬현상을 완화 시킬 수 있는 아크릴 수지와 차열안료를 혼합한 차열성 포장을 개발하였다. 태양 복사열에 의한 포장체의 온도상승을 모사한 실내 시험으로부터 60℃의 포장 온도에서 차열성 포장이 12℃ 이상의 온도 저감 효과를 나타냈다. 이러한 온도 감소 효과는 차열안료의 배합비가 증가함에 따라 증가하였고, 반면에 점도의 증가로 인하여 작업성은 떨어졌다. 이러한 결과로부터 아크릴 수지 대비 차열안료의 최적혼합비율을 15%로 결정하였다. 차열성 포장의 칸타브로 손실률은 일반 배수성 포장의 손실률 1/4 수준으로 골재 비산 저항성이 우수하게 나타났다. 휠트랙킹 시험결과 차열성 포장의 동적안정도가 일반 배수성 포장에 비해 두 배 증가하였다. 차열성 포장재의 높은 부착력으로 인하여 탈리에 의한 손상 가능성은 낮은 것으로 나타났다. 시험 시공 구간에서의 소음도 측정 시험 결과 일반 배수성 포장에 비하여 평균 3.7dB의 소음저감 효과가 있었고, 미끄럼 저항치는 일반 배수성 포장에 비해서 평균 30% 정도 높아 우수한 미끄럼 저항성을 가지는 것으로 판단된다. 투수 시험 결과 차열성 포장의 투수성은 일반 배수성 포장보다 다소 작았으나 국내 배수성 포장 기준을 만족하는 것으로 나타났다.

The indoor thermal conductivity test, unfrozen water test, and freezing pressure test were conducted on soil mixed with waste vinyl aggregate (PE aggregate). Consequently, lower thermal conductivity, less unfrozen water, and lower freezing pressure resulted from higher PE aggregate mixing ratios. Furthermore, the plate loading test and frost penetration depth test were conducted on field model road with a sub-base of PE aggregate and crushed stone. As a result, the bearing capacity of the road mixed with 10% PE aggregate exceeded the requirement, whereas frost penetration depth was reduced by 39% compared to that of using crushed stone only.

Recently, the use of eco-friendly deicer is recommended for solving problem of chloride deicing salts. The laboratory tests are often used to evaluate deicer performance, but they have been shown to correlate poorly to actual field performance. Thus, we would like to introduce the field test method for improving the performance qualification of anti-icing materials.