나무이는 감귤그린병, 제브라칩병과 같은 식물병원균의 매개충이 되는 경제적으로 중요한 해충그룹으로서, 귤나무이(Diaphorina citri Kuwayama)는 감귤산업에 큰 피해를 주는 감귤그린병(Citrus Huanglongbing Disease)을 매개하여 전 세계적으로 문제가 되고 있다. 최근 기후 온난화로 귤나무이가 유입될시 제주도를 비롯한 남부지방에서도 하우스 재배 감귤에는 충분히 월동 가능할 것으로 분석된다(감귤연구소, 2015).제주도지역이 경우, 묘목 수입에 의하여 전파될 가능성이 가장 클 것으로 예상된다. 이에 국내 유입 대비를 위한 예찰방법 및 동정법 개발이 필요한 실정이다. 제주도 지역을 2016년부터 현재까지 43지점을 조사한 결과, 18종의 나무이와 14종의 기주식물을 확인되었다. 또한 실내사육을 통해서 생육단계별 생태사진과 동정에 필요한 암수 생식기 표본, DNA 염기서열을 확보하였다. 현재까지 운향과를 기주로하는 나무이는 발견되지 않았으며 귤나무이 또한 발견되지 않았다.

사회성 말벌류의 분류학적 연구는 과거 1960-1980년도까지 1차적으로 한국산 말벌을 정리하여 그 개략적인 윤곽이 나타났으며 90년대 이후 전문 분류학자들에 의해 연구되어 현재 남한지역에서 보고된 사회성 말벌류는 총 2아과 5속 30종이다. 그러나 아직도 분류학적 논의가 필요한 종이 남아 있는 상태이며 특히 각 계급별 및 벌집의 특성은 아직 밝혀지지 않은 종들이 많은 상태이다. 최근 들어서는 외래종 말벌의 침입을 통해 전국으로 확산되고 있는 가운데 공중보건적, 경제적, 생태적 피해가 나타남에 따라 이들의 조절 및 관리에 대한 연구가 일부 진행되고 있다. 또한 기후변화 및 도시화에 의해 전국적으로 말벌류가 증가함에 따라 119 소방서의 벌집제거수가 연간 20만건을 나타내고 있으며 각종 벌쏘임 사고가 빈발하여 연간 10여명의 사망사고가 나타나고 있어 이에 대한 국가적 대책이 필요한 실정이다. 또한 최근 말벌을 이용하여 만든 노봉방주의 수요가 급증하는 가운데 이들의 과학적 검증에 대한 요구가 증가하면서 독성, 타액 등의 효능분석 및 유해성 분석도 일부 진행되고 있다. 그 외 말벌의 공격성분석, 먹이 원분석, 사냥행동 특성, 기생, 천적 등의 생태적 연구도 일부 진행 중에 있다. 이처럼 말벌에 대한 사회적 문제가 커지고 있음에도 불구하고 국내의 말벌 전문 학자 부족으로 인해 가시적인 연구 성과가 미진하며 문제 해결에 대해 제대로 대처하지 못하고 있는 상황이다.

Attitudes toward advertising as an institution remain an important research topic in developing countries. Even in the West, the issue is currently being revisited to update for various online media contexts. This paper examines attitudes toward advertising among college students in Egypt. There was little difference in attitudes depending on whether they were thinking of traditional TV advertising or advertising on social media, although they use SM much more frequently. Generally the respondents agreed with a range of issues related to the beneficial aspects of advertising, and only slightly agreed or were roughly neutral on most issues related to detrimental effects. There is strong support for laws about ‘truth-in-advertising’ and legal responsibility for claims, but only weak support for direct government control of advertising.

Asphalt pavement overlay method is one of widely chosen construction methods for remodelling existing aged concrete pavement layer. However, in this case reflective cracking is a challenging issue due to movement of transverse joints: built in existing concrete pavement layer with constant interval length. In this paper, collecting field data: collection of displacement and temperature data on existing concrete pavement layer for further complicated pavement performance analysis, was performed. To fulfil this objective, various types of thermometer were embedded into concrete layer with different depth level. Then, movement of existing concrete layer was measured numerically. Each Displacement Measuring Gauge (DMG) along with thermometer was embedded with depth of 3cm and 15cm, respectively. Additional thermometers were embedded at the middle depth of overlaid asphalt pavement layer for further extensive analysis and data collection. Total four testing sites were considered based on different asphalt mixture type and construction method. The 1st site was constructed with conventional construction approach, the 2nd site was constructed with a new pavement equipment contains simultaneous tack-coating function, the 3rd site was similar to 1st site but Guss-asphalt was constructed as a binder course, and in 4th site Noise-Reduction Porous Asphalt (NRPA) was constructed as a surface course and regular Dense Grade Asphalt (DGA) was constructed as a binder course. A field asphalt pavement layer sample coring works: along with basic material property tests, were also performed to acquire not only overlaid asphalt but also existing concrete pavement materials. This gauge measuring work in this study is an initial step therefore, long-term movement data of each pavement layer was not able to be collected, unfortunately. However through collecting and analysing initial data on each test site, two crucial findings were acquired. First, in all four tested site highest temperature variations were observed at the upper asphalt pavement layer and the variation trends decreased with increase of pavement depth (in case of concrete pavement layer, temperature and movement variations also decreased with increase of pavement depth). Secondly, when Guss-asphalt was applied as a binder course temperature variations of existing concrete pavement layer was crucially smaller than those of other comparison cases. These current findings and collected data set can provide successful input information for further pavement structure analysis such as 2D (and/or 3D) Finite Element Method (FEM) analysis as a future study.

Generally, remarkable amount of Reclaimed Asphalt Pavement (RAP) is produced annually by pavement surface cutting: due to early distress on asphalt pavement layer and remodelling construction work on existing aged-asphalt pavement layer. In South Korea, various types of research on proper and optimized RAP material development and field application (including evaluation process) are performed because of increase of existing road maintenance budget and technology. The major material of RAP is recycled aggregate coated with aged asphalt binder. The advantages of application of RAP on asphalt pavement are recyclable material proportion can be increased due to re-using of existing aggregate and eco-friendly characteristics. However, more amount of specific additives (and/or agent) needs to be implemented during production with increase amount (and/or proportion) of RAP on virgin asphalt material inevitably. This action is highly needed because of recovery of penetration grade and absolute viscosity of final production. The required amount of additives tends to be vary based on different aging level of RAP, amount of RAP and types of virgin asphalt binder. But it is well known that required amount of additives tends to be increased with increase of RAP proportion compared to virgin asphalt mixture. Moreover, it also should be known that mere increase of additives on RAP asphalt can provide negative effect on its quality and mechanical performance. In this study, high penetration grade asphalt binder: contains between 200 and 300 level of penetration grade, was used for producing RAP asphalt mixture with small amount of required additive application. After the sample preparation, various characteristics of RAP asphalt were analysed with extensive experimental work.

In this paper, first the aging level of Stone Mastic Asphalt (SMA): one of the widely applied asphalt mixture types for highway construction in South Korea, was analysed then those aging effects on various performance characteristics were studied. Then, a suitable methodology for improving performance on real asphalt pavement construction site was recommended. To fulfil the objective, Gel-Permeation Chromatography (GPC) experimental work was performed on various aged SMA mixtures by measuring Large Molecular Size (LMS) then the Absolute Viscosity (AV) value was predicted based on the findings in the previous step. As results, it was found that types of performance change on aged asphalt binders could be estimated by computed Estimated Absolute Viscosity (EAV) values. It also should be mentioned that the performances of tested SMA mixture presented negative trend after aging effect increases; even though the performance deterioration level of SMA is lower than that of regular Dense Grade Asphalt (DGA) mixture, which means proper reactions are recommended to keep its quality. Moreover, better resistance against aging effect was found by applying Hydrated-Lime (HL) or Low Density Poly-Ethylene (LDPE) compared to any other additives on asphalt mixtures. A unique Aging Quantity (AQ) model for SMA mixtures was developed by using two factors: collected aging time data set from field (and/or laboratory) and AV values based on different temperature conditions. The Predicted Absolute Viscosity (PAV) on SMA mixtures was computed by using the introduced AQ model then the aging level of asphalt binder was estimated as a final step. Additionally, five performance characteristics of asphalt binder: Dynamic Shear Rheometer(DSR) high temperature limit, Bending Beam Rheometer (BBR) low temperature limit, G*/sinδ, Creep stiffness, and m-value, were analysed. The value of AV showed the best performance for predicting and representing aging level. Finally, the aging level of given asphalt mixtures in the field can be easily predicted by choosing one of three approaches presented in this research. It can be concluded that the performance of asphalt pavement can be increased by selecting proper materials and performance prediction methodologies introduced in this study. However, only limited number of specimens were considered in this study due to limit of raw materials and laboratory equipment condition. Therefore, extensive experimental works with various types of asphalt materials are recommended for strengthen findings in this thesis as a future research.

The Semi-Rigid Pavement (SRP) mixture is composed of Gap Graded Asphalt (GGA) mixture (air void = 20~28%) and cement paste. By inserting cement paste into voids in GGA mixture, SRP can provide not only flexibility but also rigidity characteristics on pavement performance. SRP can mitigate pavement surface temperature increase during summer session, provide better smoothness and mitigate rutting distress due to heavy weight vehicles, successfully. In Japan, SRP is widely applied in cross section area, heavy vehicle parking lot and highway ticketing booth in highway network system. In South Korea, SRP was introduced and applied since 2005. However, still more researches and studies are needed to understand material characteristics and improve performance of SRP. Moreover, the current SRP system in South Korea merely follows and adapts the aggregate gradation information from Japan which needs to be amended and customized into original material (i.e. aggregate, binder and cement) situation of South Korea. In this paper, SRP system based on Stone Mastic Asphalt (SMA) mixture design originated from Korea Expressway Corporation (KEC) and enhanced cement paste with addition of fly-ash and slags was developed. In addition, an optimized proportion between asphalt mixture air voids and cement paste amount with consideration of economic benefit was introduced. Based on field evaluation process it can be said that the newly developed SRP system can successfully adapted not only in static site on highway: parking lots or ticketing booth, but also in dynamic site on highway: driving and wheel path.

The ride quality (i.e. smoothness) is a key factor for evaluating the construction quality of expressway asphalt pavement. Conventionally, three paving devices are widely used to control the surface layer thickness: leveling sensor (i.e. LS), short-range-surfacing-contact-ski (i.e. SSCS) and long-range-surfacing-contact-ski (i.e. LSCS). However, each of these levelling tools presents one major drawback. In the case of LS, if the original sub-layer evenness is poor, the final asphalt pavement surface and its smoothness will be negatively affected. The SSCS cannot assure satisfactory smoothness when relatively long paving section (in the order of 10 km) are paved. While the LSCS would reduce the drawback of the SSCS, its weight on the one hand and its length on the other discourage its use in the paving site especially for curved sections. In this paper, a next generation pavement smoothness leveling equipment, known as non-contact-digital-ski (i.e. NCDS) was implemented, evaluated and compared to the conventional equipment leveling device. The international Roughness Index (IRI m/km) was measured on sections paved with and without NCDS and the results visually and statistically compared. In addition, for the same sections, the modulus of the pavement layers was computed and compared by means of Falling Weight Deflectometer (i.e. FWD). It was observed that when NCDS is used for asphalt pavement overlay of existing concrete pavement, significant improvement in IRI (i.e. IRI<1.0m/km) and consistently uniform elastic modulus could be achieved compared to the conventional levelling and paving method.

In the second half of the twentieth century, climate scientists have observed significant climate change events. Climate change scenarios characterized by increased temperature and precipitation in urban areas have resulted in disasters such as the urban heat island effect or street flooding. In response to these extreme climate scenarios, engineers have proposed permeable pavement technology. Permeable pavement is a type of pavement that allows water to flow through existing cavities into the pavement. The benefits of permeable pavement include reducing storm water runoff, reducing the heat island effect, and improving water quality, and reducing noise. In this study, a mechanistic-empirical analysis was performed to model the performance of permeable pavement in a subtropical climate with two variations of base and soil materials under both low and high traffic scenarios. The performance criteria for fatigue cracking and rutting were used to determine the service life of the permeable pavements. Furthermore, the estimated pavement performance was used to perform the life cycle analysis of the permeable pavements. Economic, environmental, and social sustainability aspects during the construction, maintenance, and operation periods were modelled for a 20 year analysis.

Low temperature cracking on asphalt material is one of the serious distresses for asphalt pavement built in northern U.S., Europe and Canada. Thermal stress is a key factor for measuring (and estimating) the resistant capability of asphalt pavement against low temperature cracking. For this reason, many road agencies have recognized thermal stress as a crucial parameter for evaluating the low temperature performance of asphalt pavement materials. Thermal stress is conventionally computed through two steps. First, the relaxation modulus E(t) is generated thorough the conversion of the experimental creep compliance data D(t). Then thermal stress (T℃) is numerically estimated solving convolution integral. In this paper, a one-step approach to the calculation of thermal stress is proposed. This method is based on Laplace transformation. Thermal stress and corresponding critical cracking temperature obtained with single- and double-step procedure on a set of three mixtures are graphically and statistically compared. It is observed that the application of Laplace transformation provides reliable computation results of thermal stress compared to the conventional computation approach.

In case of performing asphalt pavement overlay on existing concrete pavement layer, applying asphalt emulsion tack-coating or spreading prime-coating is considered to improve adhesion between asphalt and concrete layer. After coating work is done a curing process is considered not only for promoting evaporation process in coated (and/or spread) asphalt emulsion, but also for generating a membrane which can act as a bonding agent. Finally, asphalt overlay construction is performed when this curing process is completely done. However, during asphalt overlay construction process remarkable amount of spread tack-coating layer is lost due to asphalt material transfer vehicles (e.g. trucks, approximately 40~50% of total spread tack coating material is lost). In this paper, a new pavement equipment contains simultaneous asphalt emulsion spreading ability and corresponding construction techniques are introduced. Through applying this equipment, non-stop two step sequent working process: spreading asphalt emulsion on to existing concrete pavement layer then paving asphalt material for overlay construction, is available. During pavement working process temperature of asphalt material was kept with ranged between 130ºC and 170ºC. After performing field performance evaluation, it was found that crucial improvement in pavement layer adhesion, crack and rutting resistant ability were observed compared to the conventional paving method.

We propose a speedy two-step deposit process to form an Au electrode on hole transport layer(HTL) without any damage using a general thermal evaporator in a perovskite solar cell(PSC). An Au electrode with a thickness of 70 nm was prepared with one-step and two-step processes using a general thermal evaporator with a 30 cm source-substrate distance and 6.0 × 10−6 torr vacuum. The one-step process deposits the Au film with the desirable thickness through a source power of 60 and 100 W at a time. The two-step process deposits a 7 nm-thick buffer layer with source power of 60, 70, and 80 W, and then deposits the remaining film thickness at higher source power of 80, 90, and 100W. The photovoltaic properties and microstructure of these PSC devices with a glass/FTO/TiO2/perovskite/ HTL/Au electrode were measured by a solar simulator and field emission scanning electron microscope. The one-step process showed a low depo-temperature of 88.5 oC with a long deposition time of 90 minutes at 60 W. It showed a high depo-temperature of 135.4 oC with a short deposition time of 8 minutes at 100 W. All the samples showed an ECE lower than 2.8% due to damage on the HTL. The two-step process offered an ECE higher than 6.25% without HTL damage through a deposition temperature lower than 88 oC and a short deposition time within 20 minutes in general. Therefore, the proposed two-step process is favorable to produce an Au electrode layer for the PSC device with a general thermal evaporator.

The property changes of 18, 14, and 8K green gold alloys for jewelry are observed by adding 0.0, 3.0, and 5.0 wt% of indium (In), respectively. To check the composition of the alloys, an energy dispersive spectroscopy (EDS) analysis is conducted. Color and microstructure analysis is executed through bare-eye, macro camera, UV-VIS-NIR-colormeter, and optical microscope. The melting point, wetting angle, and hardness are measured using TGA-DTA, a wetting angle tester, and a Vickers hardness tester. The EDS analysis result demonstrates that each of the green gold alloys was manufactured with purposed contents. The color analysis result shows that the color of the alloys is similar to the color of the conventional 4 wt%- Cd 18K green gold, and the green color improves as the In content increases. The micro structure analysis result demonstrates that grain refinement improves as the amount of In increases. Enhancements in the melting point, wettability, and Vickers hardness changes appear as the In content increases and Au content decreases. The hardness is up to 260, which implies good durability. Therefore, the results suggest that the proposed 18, 14, and 8K In-added green gold alloys enhance the properties of jewelry products with regard to the green color, castability, and durability.

다이옥신류(Polychlorinated dibenzo-p-dioxins and furans: PCDD/Fs)는 화학적으로 매우 안정화 되어 있으며 난분해성 이자 강한 독성을 가지고 있다. 특히 환경 매체의 오염을 통해 생태계 내 생물의 생체에 종종 축적된다. 외래종 등검은말벌은 2003년 국내 침입 후 전국적으로 확산되었으며, 최근 말벌(집)을 민간요법으로 식음하는 사례가 늘면서 이로 인한 오염물질 노출 가능성이 높아지고 있다. 본 연구에서는 도시 및 산림지역에서 말벌(집)을 채집한 후 비의도적 잔류성유기오염물질 공정시험방법에 따라 전처리 후 가스크로마토그래프/고분해능질량분석기(GC/HRMS) 를 이용하여 다이옥신류의 농도수준과 경향을 확인하였다. 농도는 WHO에서 제시한 2015 독성등가계수를 이용하여 TEQ농도(pg-TEQ/g)로 환산하였다. 그 결과, OCDD 등 일부 다이옥신 물질이 검출되었으나, 인체의 유해정도는 낮은 것으로 보인다. 그러나 다양한 지역에서의 등검은말벌 채취 및 분석, 위해성평가 등 추가연구가 필요하다.

감귤그린병(Citrus Huanglongbing Disease)은 전 세계적으로 감귤산업에 가장 큰 피해를 주는 병해로 국내 미분포종인 귤나무이(Diaphorina citri Kuwayama)가 매개충으로 알려져 있다. 바이러스에 감염된 나무는 5~12년내에 대부분 고사하며 열매는 크지 못하고 색이 들지 않는 증상을 보여 상품성을 저해시킨다. 현재 접목, 묘목, 매개충등의 유입으로 전 세계적으로 확산되고 있는 실정이다. 귤나무이의 국내 분포가능성이 꾸준히 제시되면서 유입 대비를 위한 예찰방법 및 동정법 개발이 필요한 실정이다. 제주도에는 총 33종이 분포하는 것으로 알려져 있으며(권, 1983; Cho & burckhardt, 2017) 2016년부터 지금까지의 조사로 11종의 나무이와 10종의 기주식물을 확인되었다. 귤나무가 속해있는 운향과를 기주로 하는 나무이는 발견되지 않았다.

Recently, the migration of refugees has been drastically increasing and became a global issue which indirectly affects the shipmasters, authorities and shipowners during rescue operations. The objective of this paper is to study the challenges or difficulties in rescuing refugees at sea from the perspectives of shipmasters, authorities and shipowners in Malaysia. In this study, the key challenges faced by these three groups of individuals are collected and classified based on the primary data reviewed. The interview sessions were conducted with selected expertise and the data collected are analyzed based on the Analytical Hierarchy Process (AHP) or precisely the pair-wise comparison methods. Through the calculations, the challenges are ranked from the most important challenges to the least important challenges. Furthermore, the data is analyzed by using expert judgments focusing on the relatively most important challenges faced by the three groups of individuals. Finally, the most important challenge faced by shipmasters is the safety of ships and crews, while for authorities, the most important challenge faced is delays in the initiation of rescue operations. For ship-owners, the most important challenge faced is time sensitive cargo loss. Ultimately, two suggestions have been proposed to encounter the most important challenge faced by these groups.

The goal of this study is to get a better understanding of the relationship between online customer reviews (OCRs), product returns and sales after returns in online fashion. Furthermore, we generate deeper insights about the moderating role of mobile shopping usage, product involvement and brand equity in this context. We answer our research questions by empirically analyzing a unique data set from a European fashion e-commerce company. This study links a wide range of transaction data (2.5 billion page clicks, 46 thousand different products, 700 brands, 40 product categories, 72 million sold and 33 million returned items) with a large set of OCRs (0.9 million). Our results show that positive OCRs can lead to higher sales, lower returns, and better conversion rates. Considering higher search costs on mobile devices, we reveal a weaker impact of OCRs in the mobile than in the desktop sales channel. Furthermore, in line with involvement theory, we see a significant impact of product involvement in this context such as the influence of positive OCRs is stronger for high-involvement products than vice versa. Moreover, we find strong support for statements from brand signaling literature, that OCRs matter more for weak than for strong brands.