• Natural Product Sciences
• /
• 제2권1호
• /
• pp.37-42
• /
• 1996

Several species and varieties of Allium spp. grown in Indonesia were screened for their in vitro antiplatelet aggregation activities. The extracts were also analyzed by GC for their volatile sulfur-containing compounds, and measured for their Volatile Reducing Substances (VRS) contents. Antiplatelet aggregation potencies of Allium spp. were varied among the species and varieties studied. Garlic extracts showed the greatest ability to inhibit platelet aggregation followed by extract of shallot, chive, yellow onion, and green onion. The 'Jawi' and 'local Padang' variety of garlic showed high activities with $IC_{50}$ values of 9.1 and $9.8\;{\mu}g/ml$, respectively. The local Kupang variety of shallot showed the highest antiplatelet activity among the shallot varieties evaluated, with an $IC_{50}$ value of $111\;{\mu}g/ml$. Antiplatelet aggregation activities of Allium extracts showed a positive correlation with the level of volatile compounds.

• 한국해양공학회지
• /
• 제31권4호
• /
• pp.299-307
• /
• 2017

The design of the mooring line to maintain the position of an offshore structure in rough marine environments is recognized as a very important consideration. Conventional fatigue evaluation of a mooring line was performed by considering the tensile force acting on the mooring line, but the mooring line broke after 238 days in the girassol area even though the expected fatigue life was expected to be longer. The causes of this event are known to be due to OPB/IPB (out-of-plane bending/in-plane bending) caused by chain link friction due to the excessive tensile strength of the mooring line. In this study, three models with different boundary conditions were proposed for fatigue analysis of a mooring line considering OPB/IPB. Interlink stiffness was calculated by nonlinear structure analysis and a stress concentration factor was derived. In addition, the sensitivity of interlink stiffness according to the magnitude of tensile force, large deformation effect, and coefficient of friction was analyzed, and the effect of critical elastic slip and bending moment calculation position on interlink stiffness was confirmed.

• The Journal of Asian Finance, Economics and Business
• /
• 제8권5호
• /
• pp.939-950
• /
• 2021

The purpose of this study was to measure the significance and contribution of sensory appeal, lifestyle, and health motive in determining coffee drink consumption. The theory adopted is the SOR (stimulus-organism-response) theory and the AISAS (attention-interest-search-action-share) model approach. Data was collected online in April-May 2020, and obtained 413 valid respondent data. The data were processed using SEM (Structural Equation Modeling) framework. The results showed that the variable sensory appeal of coffee drinks, lifestyle variables and health motive variables had a significant effect on coffee consumption. Of the 13 hypotheses proposed, nine hypotheses are accepted and four hypotheses are rejected. Sensory appeal has a positive effect on attitude and action of coffee consumption. Lifestyle has a positive effect on attitude, search, and action, whereas health motive has a positive effect on attitude of coffee consumption. Lifestyle variables have the greatest role in determining coffee consumption, followed by health motive variables and sensory appeal of coffee drinks. The SOR theory and the AISAS approach can both be used to analyze coffee drinking behavior. The research suggests that, to increase coffee consumption, a marketing approach should touch the lifestyle of the community and increase the promotion of the health aspects of coffee drinks.

• Journal of the Korean Wood Science and Technology
• /
• 제47권5호
• /
• pp.617-632
• /
• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• International Journal of Naval Architecture and Ocean Engineering
• /
• 제11권1호
• /
• pp.178-201
• /
• 2019

The appropriate design of a mooring system to maintain the position of an offshore structure in deep sea under various environmental loads is important. Fatigue design of the mooring line considering OPB/IPB(out-of-plane bending/in-plane bending) became an essential factor after the incident of premature fatigue failure of the mooring chain due to OPB/IPB in the Girassol region in West Africa. In this study, mooring line fatigue analysis was performed considering the OPB/IPB of a spread moored FPSO in deep sea. The tension of the mooring line was derived by hydrodynamic analysis using the de-coupled analysis method. The floater motion time histories were calculated under the assumption that the mooring line behaves in quasi-static manner. Additional time domain analysis was carried out by prescribing the obtained motions on top of the selected critical mooring line, which was determined based on spectral fatigue analysis. In addition, nonlinear finite element analysis was performed considering the material nonlinearities, and both the interlink stiffness and stress concentration factors were derived. The fatigue damage to the chain surface was estimated by combining both the hydrodynamic and stress analysis results.

• The Journal of Asian Finance, Economics and Business
• /
• 제9권5호
• /
• pp.531-539
• /
• 2022

The goal of the research is to identify the relationship between organizational justice, job satisfaction, and work attitudes in the context of job rotation. The competence and loyalty of the employees of an organization are critical to the organization's success. Therefore, organization should invest in developing their employees, including creating effective procedures and human resource management policies. A job rotation program is one of the critical policies in developing employees, as through this program employees can develop and actualize their abilities. However, there are some challenges in practice regarding implementing the procedures of job rotation. One of the challenges is related to the concept of organizational justice, which then impacts on employees' job satisfaction and work attitudes. This study was conducted in focused group discussions. The sample is 272 of a state-owned organization. In this study, the concept of organizational justice, with the dimensions of distributive justice, procedural justice, and interactional justice, were used along with the discussion of job satisfaction and other work attitudes. The results were issues of fairness in perceiving organizational justice in the job rotation context, and the most significant response lies in procedural justice.

• 한국컴퓨터정보학회논문지
• /
• 제19권10호
• /
• pp.13-21
• /
• 2014

집합 커버링 문제는 대표적인 조합 최적화 문제들 중 하나로서 n개의 열로부터 일부를 선택하여 m개의 행을 커버하되 비용을 최소화하는 문제로 정의된다. 본 논문에서는 집합 커버링 문제를 해결하기 위한 정수 계획법 기반 지역 탐색의 적용 방안을 제시하고 있다. 정수계획법 기반 지역 탐색은 이웃해를 탐색하여 현재해를 반복적으로 개선하는 지역 탐색 기법의 일종으로서 이웃해를 생성하기 위한 알고리즘으로 정수계획법을 사용한다. 본 논문에서 제시한 기법의 효과를 검증하기 위해 OR-Library의 테스트 데이터를 대상으로 실험을 수행하였다. 실험 결과, 모든 테스트 데이터에 있어서 정수계획법 기반 지역 탐색을 통해 지금까지 알려진 가장 좋은 해를 탐색할 수 있었다. 특히 4개의 테스트 데이터에 대해서는 지금까지 알려진 가장 좋은 해보다 더 좋은 해를 도출할 수 있음을 확인할 수 있었다.

• Journal of the Korean Wood Science and Technology
• /
• 제48권1호
• /
• pp.41-49
• /
• 2020

Jabon (Anthocephalus cadamba) is a fast-growing wood species that is widely utilized for light construction and other purposes in Indonesia. The objectives of the current study were to determine the effects of monoethylene glycol (MEG) and SiO₂ nanoparticles (nano SiO₂) impregnation treatment on the dimensional stability and density of jabon wood and to identify the characteristics of impregnated jabon wood. Wood samples were immersed in water (as untreated), MEG, 0.5% MEGSiO₂, then impregnated by applying 0.5 bar of vacuum for 60 min, and then applying 2.5 bar of pressure for 120 min. The results showed that impregnation with MEG and Nano SiO₂ had a significant effect on the dimensional stability of jabon wood. Polymers can fill cell walls in wood indicated by increasing weight percentgain, antiswelling efficiency, bulking effect, and density, then decreasing in water uptake value. Jabon wood morphology by using SEM showed that MEGSiO₂ polymers can cover part of the pitsin the wood vessel wall of jabon. This finding was reinforced by EDX results showing that the silicon content was increased due to the addition of SiO₂ nano. The XRD diffraction pattern indicated that MEGSiO₂ treatment increased the degree of crystallinity in wood samples. Overall, treatment with 0.5% MEGSiO₂ led to the most improvement in the dimensional stability of 5-year-old jabon wood in this study.

• 융합보안논문지
• /
• 제19권2호
• /
• pp.129-136
• /
• 2019

지상작전 시 지휘관 및 참모의 주된 업무는 지속적으로 발생되는 상황에 대처하기 위해 수행되는 의사결정의 연속이라고 볼 수 있다. 하지만 현재의 의사결정 과정은 지휘관 및 참모의 정성적인 방법에 의존하고 있기 때문에 제4차 산업혁명을 기반으로 현재 및 미래에 도입되고 있는 의사결정 도구와의 연결을 보장하기 어려운 실정이다. 본 연구에서는 지상작전과 연관된 의사결정 고려요소들의 정량화에 대해 전장정보분석(IPB) 시 접근로 평가요소들의 상대적 중요도를 AHP를 이용하여 도출하는 것을 중심으로 제시된다. 전장정보분석에서 가장 중요한 과정 중에 하나가 접근로에 대한 평가이며, 평가요소에는 목표 접근성 관측과 사계 은폐와 엄폐 장애물, 기동의 용이성 인접 접근로로의 전환 용이성을 포함하고 있다. 기존의 방식은 비교요소에 의한 방법과 장단점에 의한 비교가 있지만, 위 평가요소들의 중요도가 동등하게 적용된다는 문제점이 항상 제기되어 왔다. 전문가집단을 통한 분석적계층과정(AHP) 기법을 적용하였고, 분석결과 목표 접근성이 가장 중요한 평가요소임을 확인할 수 있었다.

• 한국미생물·생명공학회지
• /
• 제49권3호
• /
• pp.432-439
• /
• 2021

Microbial community plays important roles in the culture environment of mud crab Scylla serrata. One of the environmental management efforts for the cultivation of S.serrata is by stabilizing microorganisms involved in nitrogen cycle process. The availability of dissolved inorganic nitrogen in its culture environment under a recirculating system closely relates to the nitrogen cycle, which involves both anaerobic and aerobic bacterial activities. Anaerobically, there are two major nitrogen compound degradation processes, i.e., denitrification and dissimilatory nitrate reduction to ammonium (DNRA). This study aimed to identify denitrifying and DNRA bacteria isolated from the recirculating cultivation of S. serrata. The water samples were collected from anaerobic filters called close filter system, which is anaerobically conditioned with the addition of varying physical filter materials in the recirculating mud crab cultures. The results showed that three denitrifying bacterial isolates and seven DNRA bacterial isolates were successfully identified. The phylogenetic analysis based on 16S rRNA gene of the denitrifying bacteria revealed that HIB_7a had the closest similarity to Stenotrophomonas daejeonensis strain MJ03. Meanwhile, DNRA bacterial isolate of HIB_92 showed a 100% similarity to Bacillus sonorensis strain N3, Bacillus vallismortis strain VITS-17, Bacillus tequlensis strain TY5, Geobacillus sp. strain DB24, Bacillus subtilis strain A1, and Bacillus mojavensis strain SSRAI21. This study provides basic information denitrifying and DNRA bacterial isolates identity which might have the potential to be applied as probiotics in aquaculture systems in order to maintain optimal environmental conditions.