• Applied Chemistry for Engineering
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• v.25 no.5
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• pp.447-454
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• 2014

Organic solar cells (OSCs) have intensively studied in recent years due to their advantages such as cost effectiveness and possibility of applications in flexible devices. In spite of the high power conversion efficiency (PCE) of 10 %, the OSCs still have a draw back of their low environmental stability due to the oxidization of aluminum cathode and etching of transparent conducting oxide as electrode. To solve these problems, the inverted structured OSCs (I-OSCs) having greatest potential for achieving an improvement of device performances are suggested. Therefore, there are a lot of studies to develope of interface layer based on organic/inorganic materials for the electron transport layer (ETL) and passivation layer, significant advancements in I-OSCs have driven the development of interface functional materials including electron transport layer. Recent efforts to employing 2D/3D zinc oxide (ZnO) based ETL into I-OSCs have produced OSCs with a power conversion efficiency level that matches the efficiency of ~9 %. In this review, the technical issues and recent progress of ZnO based ETL in I-OSCs to enhancement of device efficiency and stability in terms of materials, process and characterization have summarized.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.3
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• pp.205-212
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• 2013

The objective of this study was to investigate the feasibility of replacing a conventional plate fin-tube evaporator with a spiral fin-tube evaporator by comparing the performance of domestic refrigerator-freezers adopting either the plate fin-tube evaporator or spiral fin-tube evaporator. Experiments were conducted for the domestic refrigerator-freezers using either a 2-column and 15-row plate fin-tube evaporator or three spiral fin-tube evaporators with 11, 13, and 15 tube rows (N). The optimum refrigerant charge decreased with a decrease in the number of tube rows. The power consumptions of the domestic refrigerator-freezers using the spiral fin-tube evaporators with N = 11 and 13 were 2.8% and 1.5% lower than those using the plate fin-tube evaporator, respectively. In addition, the cooling capacity of the spiral fin-tube evaporator with N = 13 was 3%-7% higher than that of the plate fin-tube evaporator under the frosting condition. In a cooling speed test, all of the evaporators showed similar performances.

• International Journal of Highway Engineering
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• v.13 no.3
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• pp.147-156
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• 2011

Since the urbanization process has been taking place, negative outcomes such as environmental pollution and traffic congestion have produced as well. Reflecting the phenomenon, our study assumed that physical structure of urban form were implicit in relation to both economic performance and cost. It can be interpreted that as the urban space has been growing bigger, economic performances such as regional product output, economy of scale and the effect of agglomeration economies are increased. On the contrary, the negative effects such as environmental pollution and traffic congestion were incurred as economic loss and expenses. It means that even though economic performance can help increase regional product output, we should consider the loss on economic expenses which are paid for social problems such as environmental pollution and traffic congestion, which are caused by urbanization. Therefore, this study aims to statistically validate the relationship between traffic congestion as the most representative economy costs and physical characteristics of urban in a large city such as Seoul and to suggest its implications. As a result of model development for empirical analysis, GRDP(0.604), the population(0.582), employment GINI coefficients(0.296), population GINI coefficients(0.254) in order led to congestion cost. We can come to the conclusion that in case of scale factor such as the population, if the population tends to concentrate, urban becomes more crowded and that if GINI coefficients (the population, employment) which are variable on inequality according to region have the disparity with surrounding areas, congestion cost is caused a lot on account of movement related with employment. In addition, this phenomenon was caused if both the population and employment were geographically biased on one side.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4523-4535
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• 2012

As a way to popularize Karatedo, a curriculum for developing excellent trainers is needed. For that, DACUM was used to specifically look into the field of duty and work that a Karatedo trainer should have, and the purpose of this study is to present fundamental data necessary for developing and organizing the curriculum of cultivating Karatedo and create a useful material that can contribute to improve Karatedo trainers' performances who are working on site. A survey using Likert scale's 7 stages was conducted on DACUM meeting data, 28 managers and 108 trainers. Based on the collected data, this study had a test in order to solve the presented subject using DACUM method and SPSS WIN Ver. 14.0. This core work through the requirements analysis process. And karate leaders the necessary knowledge, skills, and tools, and attitude analysis was carried out to perform the tasks of each. Knowledge, skills, tools and attitude for each task, toward the results of the analysis were 47 core tasks. 167 knowledge items, function 143 items, the tool 60 items, 16 attitude items reclassified a total of 18 subjects were derived. The configuration of the karate leader training program curriculum model 'Karate practical expert area', 'theory karate expert area', 'Karate gym business area experts' was composed. Basic process of how it works Step 1, Step 2 integration process, replenishment process intensified Step 3 was composed.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.10
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• pp.1518-1523
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• 2003

This experiment was conducted to investigate the effect of various feeding regimens on growth performance, nutrient digestibilities, nitrogen retention, blood urea nitrogen (BUN) concentration and feed cost in young pigs weaned at 21 days of age. One hundred twenty crossbred pigs (Landrace${\times}$Large White${\times}$Duroc, average 6.8 kg BW), weaned at 21 days of age, were allotted to 5 treatments in a 5 replicates by a randomized completely block (RCB) design. Treatments were as follow: 1) 1P (1-4 weeks: CP 23% and lysine 1.60%), 2) 2P-I (1 week: CP 23% and lysine 1.60%, 2-4 weeks: CP 21% and lysine 1.45%), 3) 2P-II (1-2 weeks: CP 23% and lysine 1.60%, 3-4 weeks: CP 21% and lysine 1.45%), 4) 2P-III (1-3 weeks: CP 23% and lysine 1.60%, 4 week: CP 21% and lysine 1.45%), 5) 3P (1 week: CP 23% and lysine 1.60%, 2-3 weeks: CP 21% and lysine 1.45%, 4 week: CP 19% and lysine 1.30%). Three different diets were formulated and supplied according to phase feeding programs. Diet 1 contains 23% crude protein and 1.60% lysine, diet 2 contains 21% crude protein and 1.45% lysine and diet 3 contains 19% crude protein and 1.30 lysine, respectively. Although there was no significant difference in growth performances, there was a beneficial effect of 3 phase feeding. The ADG was higher in 3P treatment than other treatments and it was observed clearly in late period (3-4 weeks) than in early period. Also, with increase in age, growth rate of pigs in 3P treatment was higher than that in 1P treatment approximately 37% (p=0.1379). There were no significant differences among all treatments in nutrient digestibility. The concentration of BUN was higher in pigs were fed diet containing 21% crude protein and 1.45% lysine (eg, 2P-1 and 3P) than those supplied diet containing high nutrient value at 2 week. The lowest feed cost/kg weight gain of pigs showed in 3P among treatments (p<0.05) whereas, high feed cost/kg weight gain of pigs was calculated in 1P and 2P-II treatments compared with 2P-I and 2 P-II (p<0.05), because of high milk products were used in those diet.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.4
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• pp.549-553
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• 2006

In this study, the effects of granite-grit offered free-choice on voluntary intakes of grit and subsequently on some morphologic traits of the digestive tract and performance of broilers were investigated. A total of 240 7d-old male broiler chicks (Ross 308) were allotted randomly to 10 floor pens supplied with wood shavings. The experiment lasted for 42 days. There were 2 dietary treatments, each consisting of 5 replicates. Each replicate consisted of 24 birds kept in an experimental unit with a floor size of $2{\times}2m$. Dietary treatments consisted of control (C) in which broilers were fed standard broiler rations, and acid insoluble granite-grit choice (AIGG) in which broilers were fed standard broiler rations and grit in separate troughs. Mean amounts consumed varied quite widely from week to week, but on average broilers ate 3.41 g per d per bird during the experimental period. Birds had a higher voluntary intake of granite-grit at an early age (7 to 21 d of age) than later (22 to 42 d of age). The voluntary intake of granite-grit of AIGG broilers increased (p<0.05) from 2.7 g/day at 7-14 d to 4.4 g at 15-21 d of age, and then it decreased to 3.4, 3.2 and 3.4 g/day between 22-28, 29-35 and 36-42 d of age, respectively. This level of grit intake increased (p<0.05) weights of empty gizzard (0.97 vs. 1.30 g), edible inner organs (3.51 vs. 3.69 g), and length of gut (8.86 vs. 9.01 cm) as a proportion of body weight and the content of insoluble ash (8.4 vs. 42.2 g/kg) in the faeces compared to the control group. Feeding free-choice grit had little or no effect on final live weights (2,542 vs. 2,543 g), daily gains (69 vs. 69 g), carcass weights (1,924 vs. 1,911), dressing percentages (75.6% vs. 75.1%) and feed efficiencies (1.69 vs. 1.66). Birds given grit did not gain more weight than those not given grit but they tended to have (p<0.07) lower feed intake (116.7 vs. 114.5 g), and consequently lower protein and energy intake. In conclusion, the granite-grit consumed voluntarily by broilers increased gut length and empty gizzard weight without affecting growth performance of broilers. Thus, it can be assumed that the voluntary consumption of granite-grit was too low to affect performance.

• Journal of Korea Technology Innovation Society
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• v.19 no.1
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• pp.48-79
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• 2016

Recently, to overcome the global economic recession and stimulate the sluggish economy, Korea government has adopted various policies designed to strengthen the innovative capabilities of its small or medium sized enterprises (SMEs). With our focus on ICT technology companies, this study empirically analyzes both the potentials and the limitations of the R&D information support programs which are part of these governmental efforts. Our goal is to generate insights and help develop policies based on evidence. In this study, we used statistics from 2014 on small or medium business technologies to analyze the effect that the government's R&D information support policy has had on the technological or economic performance of small or medium businesses. According to these research results, R&D support programs (assistance with R&D planning and provision of technological information) made available to small or medium businesses did have a significant correlation to technological investment. By contrast, R&D information supporting programs were found to have no direct, significant correlation to technological or economic performance. One exception was that programs that gained the benefits of R&D planning support did have a significant correlation to technological performance in the case of companies engaged in ICT research. The results of this study will provide various insights for policymakers designing policies to support technologically-driven small or medium businesses, including ICT-based companies. We anticipate that this study will be a particularly helpful guide to policy development for corporations or researchers that provide supportive information to small or medium businesses.

• Proceedings of the Korea Contents Association Conference
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• 2006.11a
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• pp.677-681
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• 2006

In this paper, we suggest the GUI Management Tool, named K-Manager, for management and service of science and technology information that stored in distributed retrieval databases. Generally, it must be adapted retrieval database system for web based S&T contents service. But, It is inconvenient contents manager or the system administrator controls information easily, because it does not support the S&T information management process like TOAD, which can use for the relation database, in information retrieval database system. Using K-Manager, content manager can process the S&T content and system manager can manage the databases easily. The proposed tool active controls information effectively which is stored in the distributed retrieval database which guarantee the safety management of the contents stored in database and operate retrieval with efficient performances. Our tool consists of two sub systems, one is content manager, the other is database manager for YESKISTI based on KRISTAL-IRMS.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.11
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• pp.1193-1203
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• 2008

An active antenna(AA) can have wider bandwidth and more gain with small antenna size than those of passive antennas. However, AA inherently generates thermal noise and spurious signals from an active device. Moreover, the spurious performance of AA is very important in a highly sensitive receiving system since it is located at the front end of the receiving system. In this study, we developed an AA with $100{\sim}500\;MHz$, having the output P1dB higher than 3 dBm and little spurious signals in real environments. To achieve such performance, we designed an AA with 3-stage amplifier using CD(common drain) FET and 2 BJTs. Its electrical performances were simulated using ADS. The measurement results for typical gain, NF, OIP3, VSWR and P1dB in the required frequency band were 9.7 dBi, 10 dB, 14 dBm, 1.7:1 and 3 dBm respectively. They are in good agreement with simulation results. The unwanted spectrum level of the proposed AA is $10{\sim}30\;dB$ lower than that of the antenna with CS(common source) FET configuration at a west suburban area of Seoul, which shows that the proposed AA can be applicable to a highly sensitive receiving system for detecting unknown weak signals mixed with broadcasting and civilian communication signals.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.45 no.6
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• pp.117-122
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• 2008

Although the pulse diagnosis is the one of the most important diagnostic process to traditional medical doctors, there is no proper communication tool between experts and trainees. In this paper, we have developed a indentation training system which consists of a hardware measuring indent pressure on artificial arm quantitatively and a software providing a indentation training program. The hardware for measurement of indent pressure profile includes 3 load cells embedded in the artificial arm, signal amplification part and digitization part, NI-USB 6009 with 200Hz sampling rate. For setting up a relationship table between weights and output voltages, 8 standard weights were used. To evaluate this hardware, 3 oriental medical specialists were involved and their indent pressure profile were recorded three times respectively. From these, it was found that pulse diagnosis process could be divided into 3 periods and the maximum load were $500g{\cdot}f$ approximately while doctors perform a pulse diagnosis. The indentation training program was implemented with LabView and designed to monitor the differences between the pressure profile of a expert and that of a trainee so to offer some visual feedback to the trainee. Also, this program could provide the trends of training performances. With this developed system, the education of pulse diagnosis is expected to be more quantitative and effective.