On the investigation of investment style allocation under the OCIO structure: Evidence from the Korean stock market

( Jeongjoon Park ),( Jaewan Bae ),( Changjun Lee ) 한국파생상품학회(구 한국선물학회) 2021 선물연구 Vol.29 No.2

Purpose - Given the importance of style allocation strategy under the outsourced chief investment officer (OCIO) structure, the authors examine the validity of style allocation strategies in the Korean stock market. The authors find that external investment agencies can improve performance by using newly suggested investment styles such as high dividend yield and low volatility as well as traditional styles. In addition, the authors find that the style combination strategies create economically large and statistically significant returns. Finally, empirical results indicate that factor timing strategies suggested in this study can improve the reward-to-risk ratio. In sum, the empirical findings indicate that external investment agencies under the OCIO structure can improve performance using active style allocation strategies.

Population dynamics of Tetranychus urticae and its predatory mites, Neoseiulus californicus and Phytoseiulus persimilis, on connected strawberry leaf arena

JeongJoon Ahn,Joon-Ho Lee 한국응용곤충학회 2008 한국응용곤충학회 학술대회논문집 Vol.2008 No.10

The two-spotted spider mite, Tetranychus urticae Koch, is one of major pests in greenhouse strawberry. Two predator mites, Neoseiulus californicus (McGregor) and Phytoseiulus persimilis (Athias-Henriot), have been widely used for control of T. urticae because they have good functional and numerical responses and searching behaviors. The study of single species releasing and combined releasing of two predatory mites, N. californicus and P. persimilis, was conducted on connected strawberry leaves. The experiments were run under laboratory conditions, 24±1oC, 50-65% RH, and a photoperiod of 16:8 (L:D) h. The excised leaf disk (diameter 3cm) of two strawberry varieties – Maehyang, Sulhyang– were placed upside down on a water-saturated cotton pad in an aluminum pan (width × length 17.4 × 21.5 cm). Twenty leaf disks were placed on each experimental set and the disks (width × length 4×5 cm.) were connected with each other for dispersing of T. urticae and its predatory mite. There were four different experiments – two strawberry varieties and two treatments (releasing single predatory mite, releasing two predator mites). The experiment sets were covered with plastic cage to protect from invading other insects and mites. All life stages of T. urticae and predatory mites were recorded until all mites were vanished. The data were transformed by ln (x+1). Repeated-measures analysis of variance was used to compare the temporal variation in the overall T. urticae and predatory mite density. The average number of T. urticae per leaf arena was significantly different among treatments in Sulhyang (Treatment, df=3, 196, F=17.86, P=0.0001; Time, df=6, 1176, F=47.76, P=0.0001; Time ×Treatment, df=18, 1176, F=22.06, P=0.0001) and in Maehyang (Treatment, df=3, 196, F=42.07, P=0.0001; Time, df=6, 1176, F=64.51, P=0.0001; Time x Treatment, df=18, 1176, F=24.19, P=0.0001). When N. californicus was introduced to P. persimilis system with diminishing prey, P. persimilis population increased more rapidly than N. alifornicus but P. persimilis was displaced by N. californicus. In single or combined releasing system, N. californicus persisted longer after prey depletion than P. persimilis. We examined population growth of P. persimilis and N. californicus in single and combined predatory mite released system with diminishing prey.

Forecasting the phenology of important lepidopterous pests, Grapholita molesta, Grapholita dimorpha and Carposina sasakii: II. Case study of apple

JeongJoon Ahn,Jiwon Kim,Seon Ah Jeong,Lalit Prasad Sah,Chuleui Jung 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.10

Grapholita molesta, G. dimorpha and C. sasakii as “internal feeders” are important apple pests in Korea. Three species overwinters around and in apple orchards. New young larvae of three species bore into new shoots or fruits and then feed inside apple. When mature larvae escape from fruits they make holes that reduces the commercial value of fruit. Therefore, understanding the phenological distribution of three species is critical to establish the precise management system for reducing three species population. The study was conducted to investigate the adult emergence of G. molesta, G. dimorpha and C. sasakii using pheromone traps and to forecast the cumulative proportion of each population. This study is second part of consecutive experiment. Data collection was carried out on three commercial apple orchards and one experimental orchard of Giran in 2010 and 2011. The experimental process was same in the study of plum. More than 50% of G. molesta male was occurred in spring season (within 500 degree-days), 2010 and 2011. The adult emergence of G. dimorpha and C. sasakii was linear and sigmoidal pattern in each year. The phenology of C. sasakii was explained well by nonlinear functions and the equation 3, 6, 8 and 11 were selected based on AICc and BIC. The selected equations were validated by the data of present year (2011) in each region. The performance of G. molesta and G. dimorpha was analyzed well by bimodal functions. The importance of phenological model is discussed to develop and maintain a more precise system for multiple pest management on apple orchard.

Spatio-temporal distribution of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) within orchard and among orchards.

JeongJoon Ahn,Yonggyun Kim,Seon Ah Jeong,Lalit Prasad Sah,Chuleui Jung 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.10

Understanding the spatial pattern of G. molesta and the temporal variation of their patterns are important to develop and maintain pest management programs in fruit orchards. The overwintering larvae of G. molesta pupate early in the spring and new adults begin a flight for several reasons such as mating, seeking resources (food or shelter) and oviposition. It was known that G. molesta presented “low movement activity” and male G. molesta flight behavior was closely related to the proximity of its host crops. Unmated males remain near the site of emergence in order to find and copulate with unmated females. The fruit-bearing status of orchards are important factors for G. molesta movement. To elucidate the spatial distribution and temporal variation of G. molesta within and among orchards, pheromone traps targeting male G. molesta were used because the trap represent a reliable and economic tool for monitoring adult G. molesta populations. The study was conducted in two apple orchards (one is isolated from other fruit orchards and another is surrounded by apple orchards), Andong and in seven plum orchards, Uiseong, 2010. Using spatial analysis by distance indices, the spatial pattern of G. molesta in each sampling date was presented. In the study of the spatial pattern within apple orchard, the index of aggregation (Ia) of isolated orchard were presented >1, indicating an aggregated distribution pattern, from monitoring results. The spatial association between successive monitoring using X (the index of spatial association) was negative during spring season and after then the value was changed to positive. In the experiment of the spatial pattern among orchards, the index of aggregation was >1 in most monitoring date and the index of spatial association was negative during early and late growing season. Factors influencing the spatial-temporal dynamics of G. molesta are discussed.

Dispersal of Tetranychus urticae and its predatory mite on connected strawberry leaves

JeongJoon Ahn,Joon-Ho Lee 한국응용곤충학회 2008 한국응용곤충학회 학술대회논문집 Vol.2008 No.05

The study was conducted to investigate dispersal of T.urticae and its predatory mite on connected strawberry leaves. The experiments were run on laboratory conditions, 24±1℃, 50-65% RH, and a photoperiod of 16:8 (L:D). The excised leaf disk (diameter 3cm) of two strawberry varieties- Maehyang, Seolhyang- were placed upside down on a water-saturated cotton pad in an aluminum pan (width x length 17.4 x 21.5cm). Twenty leaf disks were placed on each experimental set and the disks (width x length 4 x 5 ca) were connected with each other for dispersing of T. urticae and its predatory mite. There were six different experiment sets - two strawberry varieties and three treatments (no predatory mite, releasing Neoseiulus californicus, and releasing Phytoseiulus persimilis). The experiment sets were covered with plastic cage to protect from invading other insects and mites. The investigation was conducted by examining two or three times per week and all life stages of T. urticae and predatory mite were reported until all leaves were occupied by mites. Repeated-measures data were analyzed by MANOVA. The average number of T.urticae per cm2 was no significant difference between two strawberry varieties in no predatory mite system (F=0.65, p>0.4195). Although the external structure of two strawberry varieties is very similar the dispersal rate of T. urticae was different between two strawberry varieties in all experiment sets. However, the number of T. urticae per cm2 was no significant different (df=1, F=1.28, p>0.2628). Within the same strawberry variety T.urticae populations among experiment sets were significant different (df=2, F=14.95, p<0.0001 Seolhyang, df=2, F=15.03, p<0.0001 Maehyang).

Degree-day Model and Phenology of Grapholita mole (Tortricidae: Lepidoptera) in Pear Orchards

JeongJoon Ahn,Lalit Prasad Sah,Hyangmi Kim,Soonwon Lee,Chuleui Jung 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

Grapholita molesta is one of economically important pests in pear orchards and has four to five generations per year depending on food resources, geographic location, and temperature. The overwintering larvae of G. molesta pupate early in the spring and new adults start to flight for several reasons such as mating, seeking resources and oviposition. The study was conducted to develop the full seasonal phenology model of G. molesta and to investigate the phenology of G. molesta adult in pear orchards. Data collection was carried out in five pear-growing location (Anseong, Icheon, Sangju, Ulju and Naju). Three commercial orchards of each location was selected for collecting data in 2011 and 2012. The flight phenology of G. molesta was investigated by the commercial pheromone monitoring trap (GreenAgroTech) once per week. The phenology of G. molesta per generation was predicted by the relationships between degree-day accumulation above the low temperature threshold and cumulative proportion of accumulated moth caught per generation. The phenology of G. molesta per generation was calculated by Weibull 2-parameter function. Although the latitude of Sangju was higher than that of Naju, the first flight of G. molesta adult from two orchards was similar. The average number of G. molesta adult caught in every pear orchards was increased from 2011 to 2012. The occurrence of G. molesta adult was explained well by degree-day model using Weibull 2-parameter function.

The Phenology and degree-day Model of Grapholita molesta (Tortricidae: Lepidoptera) in Apple Orchards

JeongJoon Ahn,Lalit Prasad Sah,Hyangmi Kim,Soonwon Lee,Chuleui Jung 한국응용곤충학회 2013 한국응용곤충학회 학술대회논문집 Vol.2013 No.04

The study was conducted to investigate the phenology of G. molesta adult, and to develop and validate the degree-day model of G. molesta in apple orchards. It was known that G. molesta is a multi-voltine insect depending on temperature and geographic location. G. molesta damage to many economically important fruit trees such as apple and pear. Data collection was carried out in five apple-growing location (Chungju, Bonghwa, Andong, Uiseong, and Geochang) and at least three commercial orchards of each location was selected for collecting data in 2011 and 2012. The commercial pheromone monitoring trap (GreenAgroTech) was used to investigate the flight phenology of G. molesta. The relationships between degree-day accumulated above the low temperature threshold and cumulative proportion of accumulated G. molesta caught per generation were used to predict the phenology of G. molesta. The phenology of G. molesta per generation was analyzed by Weibull 2-parameter function. The generation of G. molesta was depending on local environmental conditions, specially temperature. The first flight of G. molesta adult in Chungju was later than other places. The average number of G. molesta caught in Uiseong was significanlty decreased from 2011 to 2012. The occurrence of G. molesta adult was explained well by degree-day model using Weibull 2 parameter function. The developed model system could be applied to manage G. molesta population in apple orchards.

The Evolution of Outward Processing Scheme in Korea’s FTAs: The Case of the Gaeseong Industrial Complex in Korea-ASEAN and Korea-Vietnam FTA

Jeongjoon Park 서울대학교 국제학연구소 2016 Journal of International and Area Studies Vol.23 No.1

South-North Korean trade, also often referred to as inter- or Intra-Korean trade, is politically and diplomatically justifiable but legally controversial. Under the GATT and WTO regime, regardless of kind, a treatment by a Member ‘nation’ to another must immediately and unconditionally be applied to all other Member countries in the equal manner. Because under the South Korean Constitution, North Korea is not identified as a ‘nation’ but a partial territory of the Korean peninsula, all the goods delivered in and out between the two are therefore duty-free – that is to say, no tariff is applied. From the other parts of the world, however, both South and North Korea are the independent Members of the UN, and thus provoke the non-discriminatory treatment irony. South Korea runs the Gaeseong Industrial Complex on North Korean soil, and has constantly included the special consideration for the products manufactured in the Complex and carried into South Korea under the name of outward processing scheme (OPS) in order to label them as originating from South Korea. This paper investigates the changes and developments made within such frame, particularly based upon the present schemes in Korea-ASEAN and Korea-Vietnam FTA, then suggests a more advanced model, which could be considered in Korea’s future FTA negotiations.

Spring emergence pattern and its forecasting of Grapholita molesta (Busck) (Lepidoptera: Tortricidae) in stone fruit orchards

JeongJoon Ahn,Jiwon Kim,Soon Won Lee,Chuleui Jung 한국응용곤충학회 2011 한국응용곤충학회 학술대회논문집 Vol.2011 No.05

The study was conducted to investigate the spring emergence pattern of G. molesta and to forecast the emerging time of overwintering G. molesta on tree fruit orchards. G. molesta is one of major insect pests on fruit trees in Korea. The host range of G. molesta includes many economically important tree fruit plants such as apple, pear, peach and plum. The overwintering G. molesta emerge from late March as an adult lay eggs on the shoot of peach or fruits of apple, plum and peach. Therefore, it is important to understand the biofix and to forecast the emerging peak period of overwintering G. molesta for establishing the pest management strategy. The pheromone trap of G. molesta has been utilized to monitor the population density in apple orchard. The commercial stick trap (GreenAgroTech) and lure (Z8-12:AC, E8-12:Ac, Z8-12:OH, 95:5:1) was set to monitor the population density of G. molesta on each place (56 different fruit orchards). The record of temperature was received from meteorological center close to monitoring orchards. The parameters for forecasting the emerging time and peak period of overwintering G. molesta were calculated from the results of Yang et al (1997 and 2001). Although the estimated biofix of G. molesta was not fitted well, the peak period of overwintering G. molesta was explained by linear regression model. The spring emergence pattern of G. molesta was presented differently related to host plant and geographical location. The peak period of G. molesta at the same mornitoring county was presented differently according to host plant. The synchronization between host plant and G. molesta may be studied to figure out the spring emerging time of overwintering G. molesta.

SNS를 활용한 주중 성경학교 교사들의 의사소통에 관한 사례연구

김정준(Jeongjoon Kim) 한국기독교교육정보학회 2021 기독교교육정보 Vol.- No.71

본 연구는 SNS를 활용한 교회학교 교사들의 의사소통 내용과 의미를 분석하여 자발적 교사학습공동체로서 의미를 발견하고 지원방안을 탐색하기 위한 관찰 사례연구이다. 이를 위하여 본 연구자가 협력권사로 섬기고 있는 서울 소재 예장 합동 A 교회의 사례를 살펴 보았다. 연구자는 A 교회의 주중 성경학교 시범 프로그램 저학년 교사 8명의 사전 승인을 받은 후, 2021년 5월 22일부터 28일까지 일주일간 카톡방의 의사소통 과정에 소극적으로 참여하고 자료를 수집하였다. 수집된 자료를 분석한 연구 결과를 요약하면 다음과 같다. 첫째, 교사들은 자신들이 연구하고 정리한 자료, 수집한 사진, 제작한 영상들을 공유하고 발문과 수업 전개 방향을 의논하고 평가하며 수업을 준비하였다. 둘째, 교사는 연계활동을 사전에 실행해 본 후, 경험을 공유하고 활동의 다양한 전개 방법을 의논하였다. 또한 수업을 마친 후 교사들끼리 어린이의 반응과 수업 결과물을 게시하고 공유하였다. 셋째, 교사들은 일상적 삶에서 겪는 문제를 나누고, 기도를 부탁하거나, 서로를 위해 기도하고 안부에 관심을 가졌다. 교사들은 공유한 자료, 제안한 아이디어를 칭찬하고 격려하였으며 이 사역을 함께 할 수 있다는데 감사했다. 특히, 교사들은 수업 준비와 실제 수업을 통해 배운 것과 받은 것들에 대해 감사하였다. 넷째, 교사들은 교회에서 제공하는 교사교육에 그치지 않고 수업의 질을 높이기 위해 자발적으로 공부하고 체득한 지식을 함께 공유하고, 문제를 해결하며 정서적으로 상호 지지하고 친밀한 교제를 나누는 교사학습공동체로 의미를 부여할 수 있었다. 코로나 팬데믹이 발생하기 전까지 한국교회는 시간적 제약으로 인하여 지속적인 교사교육을 하는 데 어려움이 많았다. 그러나 비대면이 새로운 일상이 된 지금, SNS를 활용한 교회학교 교사학습공동체의 형성은 교회학교 수업의 질을 제고하고 교사전문성을 높여 “스스로 그리고 함께” 참여하는 교회학교 교사교육의 새로운 가능성을 보여준다. This study is an observational case study to analyze the communication content and meaning of church school teachers using SNS. For this purpose, it was examined the case of Presbyterian Church A in Seoul. The researcher passively participated in the communication process of the Kakao Talk room, and collect data for a week from May 22 to 28, 2021 after receiving the prior approval of 8 teachers in the weekday Bible School pilot program of Church A. The results of the study analyzing the collected data are summarized as follows. First, the teachers prepared their own class by sharing the materials, the photos, and the videos and discussed and evaluated the questions and lesson plan. Second, the teacher implemented the hands-on activity in advance, the experience was shared and the application of the activity was discussed. After class, they posted and shared children"s reactions and portfolios. Third, the teachers shared the difficulties in their daily life, asked for prayers. Teachers praised and encouraged the shared materials and suggested ideas for class preparation, and were grateful to be able to do this service together. Finally, the teachers created a community that cooperated and supported each other. In particular, the teachers were grateful for what they had learned and received through the midweek Bible school. This researcher was able to observe the characteristics of the teacher learning community. Teachers did not stop at the one-sided teacher education provided by the church, but voluntarily study and share to improve the quality of their classes, solve problems, emotionally support each other with close fellowship. Before the corona pandemic, church schools in Korea had many difficulties in providing continuous teacher education due to time constraints. This is a case of new hope that teacher learning community using social media can improve the quality of church school classes and raise teacher professionalism.