• KSII Transactions on Internet and Information Systems (TIIS)
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• 제12권10호
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• pp.4835-4855
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• 2018

In this paper, we study the sparse signal recovery that uses information of both support and amplitude of the sparse signal. A convergent iterative algorithm for sparse signal recovery is developed using Majorization-Minimization-based Non-convex Optimization (MM-NcO). Furthermore, it is shown that, typically, the sparse signals that are recovered using the proposed iterative algorithm are not globally optimal and the performance of the iterative algorithm depends on the initial point. Therefore, a modified MM-NcO-based iterative algorithm is developed that uses prior information of both support and amplitude of the sparse signal to enhance recovery performance. Finally, the modified MM-NcO-based iterative algorithm is used to estimate the time-varying sparse wireless channels with temporal correlation. The numerical results show that the new algorithm performs better than related algorithms.

• 대한토목학회논문집
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• 제34권6호
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• pp.1893-1899
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• 2014

본 연구는 노무중심의 전문건설업체의 경영성과지표와 건설경기지표와의 상관성 분석을 통해 노무중심의 전문건설업체의 대응전략을 제시하는 것을 목적으로 수행되었다. 노무중심의 전문건설업체는 건설수주액이 유동자산회전율에 장기적으로 영향을 미치고 있다. 이는 인력확보를 위해 유동자산을 운용하고 있기 때문인 것으로 판단된다. 즉, 노무중심의 전문건설업체는 특정 자재 혹은 장비에 대한 확보가 아닌 근로자의 수급에 초점을 맞추고 있기 때문에, 원활한 인력수급을 위해 유동부채 해결을 위한 유동자산을 운영하여 매출액 증가를 도모하기 때문인 것으로 판단된다.

• 한국식생활문화학회지
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• 제32권6호
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• pp.527-533
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• 2017

The purpose of this study was to investigate on the characteristics of the use of a fine dining restaurant using NVivo 11 qualitative analysis. As a result, customers using the fine dining restaurant were aware that the fine dining restaurant was a special and expensive restaurant, serving a variety of food with luxurious food, service and ingredients. The result of motivation for using the fine dining restaurant was food, specialty, atmosphere, luxury, service. Basically, it is natural to visit restaurant to eat, but it is special in using fine dining restaurant, we were able to find that it was to visit, to eat atmosphere and luxurious service and delicious food. The results of using the benefits of using a fine dinning restaurant show that the benefits of food, dining atmosphere, specialty, service, variety, and meals are high, specialty, service, variety of meals, price, delicious, newness, and timely benefits. The result of customers' use loss when using the fine dining restaurant shows the loss of food, specialty, service, price, atmosphere, variety, and luxurious. In this regard, it is estimated that customers often see losses as a result of lower than expected customers when using fine dinning restaurants. Therefore, it is thought that this research will help the establishment of differentiated marketing information for the restaurant company through continuous research on the fine dining restaurant which is recognized by the users.

• 한국건축시공학회지
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• 제8권5호
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• pp.67-73
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• 2008

Recent trends in construction towards larger scale and taller buildings are causing problems by ineffective existing management approach in construction industry have emerged. Delivering necessary materials and mobilizing the human resources and equipment In a timely manner to keep labor on schedule have become a critical issue to be addressed. In particular, many specialty contractors carrying out multiple projects have been experiencing difficulties mobilizing the manpower on time and in right places due to poor communication at each stage of labor supply, resulting in waste of valuable resources. Hence, it's imperative for the specialty contractors to obtain specific information on labor demand so as to set up a communication and labor management system to ensure the right human resources will be mobilized in the right place at the right time. The study therefore is aimed at developing an optimal human resources management system for specialty contractors performing multiple projects. To that end, the study is focused on rebar and concrete work. The outcome of the study is expected to help allocate the right human resources to the right place in a timely fashion, thereby achieving an effective workflow at construction sites.

• Journal of Microbiology and Biotechnology
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• 제21권7호
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• pp.697-702
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• 2011

A strain of the cyanobacterium Arthrospira was isolated from Lake Chahannaoer in northern China and was characterized according to microscopic morphology, photosynthetic oxygen-evolving activity, growth rate, and nutritional profile. Compared with thermophilic Arthrospira species occurring naturally in tropical and subtropical lakes, this isolate is mesophilic and grows optimally at ${\sim}20^{\circ}C$. The total protein, fatty acid, phycocyanin, carotenoid, and chlorophyll a contents were 67.6, 6.1, 4.32, 0.29, and 0.76 grams per 100 grams of dry weight, respectively. The strain is rich in polyunsaturated fatty acids (PUFAs). An essential omega-3 fatty acid, docosahexaenoic acid (DHA), was detected, and ${\gamma}$-linolenic acid (GLA) and DHA accounted for 28.3% of the total fatty acid content. These features of this newly isolated strain make it potentially useful in commercial mass culture in local areas or as a biofuel feedstock. It is also an alternative resource for studying the metabolic PUFA pathways and mechanisms of cold stress tolerance in cyanobacteria.

• 한국안전학회지
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• 제36권2호
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• pp.18-25
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• 2021

Specialty contractor facilities, which involve a combination of welding and commissioning, face a high risk of serious accidents such as fire, explosion, and suffocation associated with welding work, nitrogen, and argon use. In such facilities, the organizational safety culture has considerable impact on the frequency of accidents. In this study, a safety culture evaluation was conducted on specialty contractors. NOSACQ-50, a standardized survey method on safety culture, was selected as an assessment tool to evaluate the safety culture in specialized construction companies that could not afford to invest heavily in safety. The self-administered questionnaire survey was conducted with 201 workers of four construction companies and the results were analyzed. It was found that in companies with low safety culture, the occurrence of irrationality was 66.0%, while in companies with high safety culture, the occurrence of irrationality was 42.6%. Thus, the difference in the occurrence of irrationality by safety culture was statistically significant. The difference in safety culture level according to the experience of occurrence of irrationality was also significant. It was also found that the higher the belief in safety management authorization, safety responsibilities of managers, worker safety priorities, and safety system effects, the lower the probability of irrationality.

• 분석과학
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• 제34권4호
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• pp.172-179
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• 2021

Oleanane-type triterpenoids exist as secondary metabolites in various plants. In particular, soyasaponin, an oleanane-type triterpenoid, is abundant in the hypocotyl of soybean, one of the most widely cultivated crops in the world. Depending on their chemical structure, soyasaponins are categorized as group A saponins or group DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one) saponins. The different soyasaponin chemical structures present different health functionalities and taste characteristics. However, conventional phenotype screening of soybean requires a substantial amount of time for functionality of soyasaponins. Therefore, we attempted to use liquid chromatography with a photodiode array detector and tandem mass spectrometry (LC-PDA/MS/MS) for accurately predicting the phenotype and chemical structure of soyasaponins in the hypocotyl of five common soybean natural mutants. In this method, the aglycones (soyasapogenol A [SS-A] and soyasapogenol B [SS-B]) were detected after acid hydrolysis. These results indicated that the base peak and fragmentation differ depending on the chemical structure of soyasaponin with aglycone. Thus, a fragmentation database can help predict the chemical structure of soyasaponins in soyfoods and plants.

• 한국가스학회지
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• 제24권5호
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• pp.74-81
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• 2020

일반적으로 반도체를 제조할 때는 인화성, 독성, 부식성의 유해·위험물질이 다수 사용되며, 특히 화학적 증착(CVD), 식각(Etch) 등의 공정에서는 특수가스를 사용하여 반도체를 제조하고 있다. 특수가스는 압축 또는 액화가스의 상태로 용기에 충전되어 있는데, 특수가스를 반도체 제조공정에 공급하는 설비로서 가스캐비닛(Gas Cylinder Cabinet)이 사용되고 있다. 이러한 가스공급시스템 내에서 실린더 이상 발생 시 배관·계측기 등 공급시스템의 안전 확보를 위해 가스실린더에 설치된 압력방출장치를 통해 가스가 방출하게 되는데, 이 경우 가스캐비닛 내부에 방출되는 가스가 캐비닛 외부로 누출될 위험성이 존재한다. 따라서 가스캐비닛 내부의 유체유동을 분석하여 누출에 따른 위험성을 파악하고 이에 대한 위험도 감소를 위한 대책을 제시하고자 한다.

• Journal of Microbiology and Biotechnology
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• 제25권12호
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• pp.2116-2124
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• 2015

To understand the effects of physicochemical factors on nitrite transformation by microalgae, a lipid-rich Chlorella with high nitrite tolerance was cultured with 8 mmol/l sodium nitrite as sole nitrogen source under different conditions. The results showed that nitrite transformation was mainly dependent on the metabolic activities of algal cells rather than oxidation of nitrite by dissolved oxygen. Light intensity, temperature, pH, NaHCO₃ concentrations, and initial cell densities had significant effects on the rate of nitrite transformation. Single-factor experiments revealed that the optimum conditions for nitrite transformation were light intensity: 300 μmol/m²/s; temperature: 30℃ pH: 7-8; NaHCO₃ concentration: 2.0 g/l; and initial cell density: 0.15 g/l; and the highest nitrite transformation rate of 1.36 mmol/l/d was achieved. There was a positive correlation between nitrite transformation rate and the growth of Chlorella. The relationship between nitrite transformation rate (mg/l/d) and biomass productivity (g/l/d) could be described by the regression equation y = 61.3x (R² = 0.9665), meaning that 61.3 mg N element was assimilated by 1.0 g dry biomass on average, which indicated that the nitrite transformation is a process of consuming nitrite as nitrogen source by Chlorella. The results demonstrated that the Chlorella suspension was able to assimilate nitrite efficiently, which implied the feasibility of using flue gas for mass production of Chlorella without preliminary removal of NO_X.

• 간호행정학회지
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• 제5권1호
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• pp.99-111
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• 1999

The purpose of this study was to investigate the relationship between public health nurse's decentralization, participation of decision-making and organizational commitment and to provide basic data for the improvement of public health nurse's organizational effectiveness. Data were collected from Aug. 1 to Aug. 30, 1998 (collection rate-96%) through questionnaires by 163 public health nurses working in Taejon and Chungnam. The instruments were used Van de Ven and Ferry's Job Authority scale, Hage and Aiken's Hierarchy of Authority scale. Participation of Decision-making scale. and Mowday's Organizational Commitment Questionnaires. Collected data were analyzed by SPSS PC+. The results were as follows 1. There were significant differences of age(P<.05), career, spending time for major study, and experience who called expert(P<.01) to decentralization. 2. There were significant differences of career (P<.05), educational level, and spending time for major study(P<'OOl) to participation of decision-making. 3. There were significant differences of career. spending time for D1ajor study, self-evaluation to specialty(P<.01) and experience who called expert (P<.001) to organizational commitment. 4. 1) A significant correlation was found between decentralization and self-evaluation to specialty (P<.05), age, career, spending time for major study, and experience who called expert (P<.01.). 2) A significant correlation was found between participation of decision-making and self-eval-uation to specialty(P<.05), age, career, spending time for major study, experience to call expert, and decentralization (P<.01). 3) A significant correlation was found between organizational commitment and age(P<.05). career. spending time for major study, self-eval-uation to specialty, experience who called expert. decentralization, and participation of decision-making (P<.01). 5. Decentralization w·as the best predictor of or ganizational commitment(17%), also experience who called expert, self-evaluation to specialty explained the organizational commitment.