Sweet potato (Ipomoea batatas L.) is an essential crop in the Paraguayan diet. It plays a crucial role in food security. It is a source of income for family agriculture. It has a significant potential to adapt to various climatic and soil conditions in Paraguay, making it a promising crop for improving productivity. However, Paraguay faces a deficit in the development of sweet potato cultivation technology, resulting in a low productivity of 5.3 ton/ha. Efforts have been made to collect and characterize sweet potato genotypes, covering a diversity of native varieties. These efforts have laid the groundwork for future sweet potato research and development. Still, ongoing research and development of strategies are needed to address existing challenges of improving genetic resource traits and developing cultivation technology and to fully exploit growth opportunities in this sector. This review summarizes sweet potato cultivation in Paraguay, focusing on several key technical aspects. It analyzes current market situation and production conditions as well as the availability of genetic materials adapted to different ecoregions. Additionally, it explores prospects for the development of advanced sweet potato crops, including the production of high-quality, virus-free sweet potato plants with improved productivity.

In this study, we undertook detailed experiments to increase hydrogen production efficiency by optimizing the thickness of titanium dioxide (TiO2) thin films. TiO2 films were deposited on p-type silicon (Si) wafers using atomic layer deposition (ALD) technology. The main goal was to identify the optimal thickness of TiO2 film that would maximize hydrogen production efficiency while maintaining stable operating conditions. The photoelectrochemical (PEC) properties of the TiO2 films of different thicknesses were evaluated using open circuit potential (OCP) and linear sweep voltammetry (LSV) analysis. These techniques play a pivotal role in evaluating the electrochemical behavior and photoactivity of semiconductor materials in PEC systems. Our results showed photovoltage tended to improve with increasing thickness of TiO2 deposition. However, this improvement was observed to plateau and eventually decline when the thickness exceeded 1.5 nm, showing a correlation between charge transfer efficiency and tunneling. On the other hand, LSV analysis showed bare Si had the greatest efficiency, and that the deposition of TiO2 caused a positive change in the formation of photovoltage, but was not optimal. We show that oxide tunneling-capable TiO2 film thicknesses of 1~2 nm have the potential to improve the efficiency of PEC hydrogen production systems. This study not only reveals the complex relationship between film thickness and PEC performance, but also enabled greater efficiency and set a benchmark for future research aimed at developing sustainable hydrogen production technologies.

This study aimed to grow single crystals with low dislocation density using a heat exchange method using room temperature water, and investigated the effect of the structure of the heat exchanger under the crucible on the defects and dislocation density of the single crystals and the shape of the solid-liquid interface of the crystals, and obtained the following conclusions. The dislocation density of sapphire single crystal grown at 2,200℃ for 30 min and a growth rate of 0.2℃/min was 0.92x103pcs/㎠. Mo guard was used to stabilize the solid-liquid interface grown from seeds, and sapphire single crystals with a diameter of 130㎜ and a height of 75㎜ were grown.

본고는 기술혁신과 경제성장 간의 관계에 대한 연구동향을 비판적으로 검토한 다. 경제성장에서 혁신의 역할에 대한 여러 가지 입장들이 존재하며 이러한 입장들에 따라 그러한 연구동향을 정리한다. 신고전파의 성장론, 국가혁신체제론, 기술역량론, 경제추격론 등의 관점에 따라 한국을 대상으로 한 기술혁신과 경제성장에 관한 국내⋅외 연구가 본고의 검토대상이다. 이러한 비판적 검토와 성찰을 통해 앞으로의 연구과제들을 제시한다.

이 연구는 중국 내몽고 쿠부치사막지역의 사막화확산 방지를 위한 사막복구조림을 실시함으로써 장기적으로 사막화지역에 적합한 사방기술을 향상시키는데 기여하고자 수행하였다. 연구지역은 모래가 약 97%로 식재시 지속적인 수분공급이 필요하고, 토양pH가 7.2~7.9인 약알칼리성토양으로 토양양료가 대단히 부족한 상태로 나타났다. 우리나라 산림청이 조림한 지역에서 양수(楊樹, Populus simonii Carr.)의 평균활착률은 87.8%로 나타난 반면, 사류(沙柳, Salix gordejevaii Chang et. Skv.) 평균활착률은 76.8%로, 양수보다 저조하였다. 양수의 평균 신초생장량은 50.4 cm로 나타났고, 사류의 평균 신초생장량은 67.8 cm로 나타나 신초생장량은 사류가 양수보다 높은 것으로 나타났다. 경기도가 조림한 지역에서 양수의 평균활착률은 89.5%로 나타난 반면, 사류의 평균활착률은 68.3%로 양수보다 현저히 낮아, 보식이 필요한 것으로 나타났다. 양수의 평균 신초생장량은 56.7 cm로 나타났고, 사류의 평균 신초생장량은 56.9 cm로 나타나 두 수종 간 차이는 없는 것으로 나타났다.

The church growth movement, which is one of the most influential school of mission theology in the 20th century, was born in the postcolonial turmoil which traditional Western churches began to experience stagnation and decline on the home front in North America as well as Europe. In this climate of uncertainty, the research of Donald A. McGavran who had been influenced by the research project of J. Wascon Pickett for the church growth in India, questioned the status quo in missions. This produced The Bridges of God (1955) which suggests new ways to envision the missionary task of the churches. Later on McGaveran’s church growth theories based on research continually challenged the traditional mission strategies and suggested more effective and culturally sensitive ways to win people to Christ. Under his influence, church growth, together with his strong recommendation to adopt research for the church growth, became an indispensable and essential] condition of missions. It is because effective mission strategy based on research for church growth is an indicator of faithfulness to God's command to him. Whereas early church growth movement was mainly concerned with the twothird world church, in 1970s it had been applied into the North American church. Later on many institutes of church growth and church growth scholars have influenced missiology through the different research models. However, it is notable that, while social scientists focus on the contextual factors over which the church have no control, McGavran’s research paradigm usually emphasizes on institutional factors over which the church has control. Nevertheless, it does not discard its contextual factors. By accepting the methodologies of social sciences, the church growth movement has continually developed the effective manuals for research to standardize the research procedures. Although research is not a perfect tool for church growth, strategic research for church growth may well be the most important legacy of church growth movement.

본 연구는 병원에서 원예치료 프로그램으로 식물을 원예용 상토, 분갈이 용토, 물을 이용한 재배방법으로 식물을 식재한 뒤 병원과 똑같은 환경의 조건 내에서 토양과 수질에 병원성 미생물을 조사하고, 식물 생육의 변화를 알아보기 위해 수행되었다. 토양 유해 미생물을 조사하 기 위하여 원예활동에서 가장 많이 사용되고 있는 헤테라(Hedera helix L.), 테이블 야자(Chamaedorea elegans)를 원예용 상토(팜한농), 분갈이 용토(흥전농산), 수돗물(경산)을 이용한 수경재배로 12cm 플라스틱 화분에 각각 이식하였다. 실험 장소는 병원환경과 비슷한 온도 인 20~23℃, 습도 60~70%, 광도 1000Lux로 설정한 실내공간에서 2017년 2월 27일부터 5월 1일까지 63일간 실시하였으며 4일 간격으로 50mL씩 관수하였다. 이식 전 원예용 상토, 분갈이 용토, 수돗물의 E. coli O157:H7과 Salmonella spp.을 분석하였으며 실험 마지막 날에도 식물 근권에 위치한 토양을 채취하여 유해미생물을 분석하였다. 또한 병원과 비슷한 환경조건에서 10주간 재배하는 동안 일주일 간격으로 초장, 엽장, 엽폭과 엽수, 엽록소 함량을 측정하였다. 연구 결과는 다음과 같다. 첫째 토양 내 병원성 미생물 분석 결과 이식전과 실험 마지막 날 모두 원예용 상토, 분갈이 용토, 수경재배 모두 E. coli O157:H7과 Salmonella spp.은 검출되지 않았다. 이는 오염된 토양이 아닌 한 토양 자체 내에서 유해 미생물이 발생되지 않았고 병원 내 주변 환경보다는 공기 중 미생물 농도에 따라 영향을 미친다(Jaffal et al., 1996)는 연구 결과와 맥을 같이 하고 있다. 둘째 식물 생육 변화를 관찰한 결과 병원과 동일한 환경조건아래에서 아이비와 테이블 야자의 생육변화가 현 저히 차이가 났다. 먼저 아이비의 초장은 수경재배(19.2cm)>원예용 상토(10.6cm)>분갈이 용토(7.2cm) 순으로 증가하였으며 엽수는 원예 용 상토(37.6)>수경재배(30.3)>분갈이 용토(25.0)순으로 증가하였다. 엽록소 함량으로 추정한 결과 아이비는 이식한 뒤 원예용 상토, 분갈 이 용토, 수경 재배 모두 35일이 지난 시점부터 엽록소 함량이 떨어지기 시작하였다. 그중 수경재배에서의 아이비는 원예용 상토의 2배, 분 갈이 용토의 3배만큼 엽록소 함량이 급격히 떨어졌으며 잎이 고사하여 떨어지는 현상도 나타났다. 테이블 야자는 원예용 상토, 분갈이 용 토, 수경재배 모두 초장의 성장률은 극히 적은 변화를 보였지만 그중에서 원예용 상토에서 제일 높은 증감률을 보였다(0.39cm). 엽록소 함 량은 28일 지난 시점부터 낮아지기 시작하였으며 수경재배를 한 테이블 야자의 엽록소 함량이 제일 급격히 떨어지는 것을 알 수 있었다. 원 예활동 시 치료의 목적으로 식물의 빠른 성장을 보기 위해선 아이비, 테이블야자 모두 원예용 상토에 식재하는 것이 효과를 줄 수 있다. 또 한 수경재배를 통한 원예활동 시 어떠한 영양분을 첨가하지 않았기 때문에 35일이 지나면 영양분을 첨가해 주거나 병실 내에서 제거해주 는 것이 좋을 것으로 사료된다

The objective of the present study was to perform a comparative analysis of the chemical properties of the cultivation site soil and growth characteristics of organically and conventionally cultivated ginseng (Panax ginseng C. A. Meyer). Organically and conventionally cultivated ginseng samples (4-, 5-, and 6-year-old) were collected from 52 fields at 14 locations throughout Korea. The samples were collected over three years from 2013 to 2015, with the collection period between October and November of each year. In order to increase the yield of organically cultivated ginseng, the amount of nutrients was increased to match that of the conventional cultivation system, which highlights the need for proper management in accordance with the standards for chemical properties of soil. Growth duration of organic ginseng was ≥60 days shorter than that of conventional ginseng and its average yield per 1ha was 60% than that of conventional ginseng. Root weight of organically cultivated ginseng was approximately 54% that of conventionally cultivated ginseng. Rhizome diameter and body shape index of organically cultivated ginseng were lower than those of conventionally cultivated ginseng, indicating that organically cultivated ginseng was thinner and longer than conventionally cultivated ginseng. Root length was greater in 5-year-old conventionally cultivated ginseng with a low percentage of paddy-upland rotation fields. The number of rootlets was lower in 5- and 6-year-old organically cultivated ginseng with a high percentage of direct seeding cultivation. Dry weight was distinctly lower in 5- and 6-year-old organically cultivated ginseng with early defoliation than that of conventionally cultivated ginseng. Incidences of notched belly and root rot tended to be higher in conventional cultivation, with the incidence of notched belly being distinctly higher in 4- and 6-year-old roots and root rot being more prevalent in 5- and 6-year-old roots. Red discoloration and eelworm damage, which are highly affected by soil moisture, were most common in the organically cultivated 4-year-old roots. Organically cultivated ginseng showed early defoliation than conventionally cultivated ginseng, as a result, its yield and weight were low, while the incidence of physiological disorders was low. In order to increase the yield of organically cultivated ginseng, studies on cultivation technology that can overcome early defoliation, as well as soil moisture management that can minimize physiological disorders, are required.

Recent years, there is increasing demand for seedlings of Daphniphyllum macropodum. However, the bare-root nursery of the species has been reported to be challenging due to meteorological disasters caused by climate change. The study aims to investigate the appropriate levels of shade and fertilization of container-grown D. macropodum, which has shade tolerance in seedling stage. The shading treatment was regulated with the shading level of full sun, and 35%, 55%, 75% of full sun. The fertilizing level was made by regulating Multifeed 19 (N:P:K =19:19:19, v/v) with 1000mg·L-¹, 2000mg·L-¹, 3000mg·L-¹, together with the control. The height was indicated to be the highest in 3000mg·L-¹ under 55% of shading. The root collar diameter was surveyed to be the highest in 1000mg·L-¹ and 3000mg·L-¹ of full sun. A case of the whole dry mass production was surveyed to be the highest in 3000mg·L-¹ under 55% of shading and 2000mg·L-¹ under 35% of shading. Moreover, the study is to explore the possibility of production and sound growth of D. macropodum seedlings by container nursery; consequently, the result is expected to provide the production method of the seedlings of D. macropodum that is to overcome meteorological disasters from bare-root nursery.