The volatilization of alkali ions in (K,Na)NbO3 (KNN) ceramics was inhibited by doping them with alkaline earth metal ions. In addition, the grain growth behavior changed significantly as the sintering duration (ts) increased. At 1,100 °C, the volatilization of alkali ions in KNN ceramics was more suppressed when doped with alkaline earth metal ions with smaller ionic size. A Ca2+-doped KNN specimen with the least alkali ion volatilization exhibited a microstructure in which grain growth was completely suppressed, even under long-term sintering for ts = 30 h. The grain growth in Sr2+-doped and Ba2+-doped KNN specimens was suppressed until ts = 10 h. However, at ts = 30 h, a heterogeneous microstructure with abnormal grains and small-sized matrix grains was observed. The size and number of abnormal grains and size distribution of matrix grains were considerably different between the Sr2+-doped and Ba2+-doped specimens. This microstructural diversity in KNN ceramics could be explained in terms of the crystal growth driving force required for two-dimensional nucleation, which was directly related to the number of vacancies in the material.

본 연구는 졸업학년 간호대학생의 성장마인드셋과 셀프리더십이 진로준비행동에 미치는 영향을 규명하고자 시도된 서술적 조사연구이다. 자료수집 기간은 2021년 11월 1일부터 30일까지이며, 연구대상 은 G시와 J도에 소재한 3개 대학교 간호대학생 173명이다. 자료 분석은 SPSS 26.0 프로그램을 이용하여 t-test, ANOVA, 기술분석, Pearson‘s correlation, 통제회귀분석을 실시하였다. 연구결과, 성장마인드셋은 셀프리더십(r=.343, p<.001) 및 진로준비행동(r=.373, p<.001)과 정적상관을 보였으며, 셀프리더십과 진로 준비행동도(r=.515, p<.001) 정적상관을 보였다. 또한, 셀프리더십(β=.435, p<.001)과 성장마인드셋(β =.193, p=.005)은 진로준비행동에 정적영향을 미치며, 진로준비행동을 32.0% 설명하였다. 이에 졸업학년 간호대학생의 진로준비행동을 촉진하기 위한 방안으로 셀프리더십과 성장마인드셋의 함양을 위한 실제적 인 전략이 필요함을 시사한다.

The grain growth behavior in the (1-x)K0.5Na0.5NbO3-xCaZrO3 (KNNCZ-x) system is studied as a function of the amount of CZ and grain shape. The (1-x)K0.5Na0.5NbO3-xCaZrO3 (KNNCZ-x) powders are synthesized using a conventional solid-state reaction method. A single orthorhombic phase is observed at x = 0 – 0.03. However, rhombohedral and orthorhombic phases are observed at x = 0.05. The grain growth behavior changes from abnormal grain growth to the suppression of grain growth as the amount of CaZrO3 (CZ) increases. With increasing CZ content, grains become more faceted, and the step-free energy increases. Therefore, the critical growth driving force increases. The grain size distribution broadens with increasing sintering time in KNNCZ-0.05. As a result, some large grains with a driving force larger than the critical driving force for growth exhibit abnormal grain growth behavior during sintering. Therefore, CZ changes the grain growth behavior and microstructure of KNN. Grain growth at the faceted interface of the KNNCZ system occurs via two-dimensional nucleation and growth.

본 연구는 Holstein 거세 비육우의 성장 단계에 따른 채식 및 반추행동에 미치는 영향을 규명하기 위하여 실시하였다. 실험에 사용한 공시 Holstein 거세우는 육성 단계(T1), 비육전기 단계(T2) 그리고 비육 후기 단계(T3)을 각각 3두씩, 총 9두를 3처리 3반복으로 배치하였다. 사료급여는 농후사료 체중의 1.62%, 조사료는 자유 채식시킨 후 육안으로 48시간 채식 행동관찰을 실시하였다. 체중대비 건물섭취량은 T1구(2.21%) 가장 높게 T3구 (1.39%)가 가장 낮게 나타났다. 채식시간은 T1, 반추시간은 T2 그리고 휴식시간은 T3 구에서 높게 나타났다(p<0.05, 0.01). 저작 시간은 T1 및 T2구에 비하여 T3구가 현저히 떨어지는 것으로 나타났다(p<0.01). 식괴수와 총 저작수는 다른 처리구에 비하여 T2구가 유의적으로 높게 나타났다(p<0.01). 그러나 식괴 당 저작수 및 분 당 식괴수는 T1구가 높게 나타났지만 상호 처리간 유의적인 수준은 나타나지 않았다. 음수 회수 및 배분 회수는 처리 구들 간에 유의적인 차이가 없었다. 그러나 배뇨 회수는 어린 단 계인 T1 구에서 유의적으로 높게 나타났다(p<0.01). 음수 시간, 배분시간, 배뇨시간은 T1 구에서 높게 나타났지만, 개체 차이가 심하여 유의적인 차이는 보이지 않았다. 이상의 결과를 종합하면 비육후기 단계(T3)는 육성(T1) 및 비육전기(T2)비하여 체중대비 채식량이 낮음에 따라 채식시간 반추시간은 줄어들고 휴식시간은 증가하는 것으로 나타났다. 또한 T3구는 총 식괴수 및 총 저작수도 떨어지는 것으로 나타났다.

리더의 행동은 부하, 즉 구성원들에게 긍정 또는 부정적 영향을 미칠 수밖에 없다. 그것은 리더가 가진 권력의 영향 때문일 것이다. 리더십 연구는 대부분 긍정적 측면에서의 리더십 효과를 탐구해왔다. 이는 리더십이라는 용어가 내포하는 긍정적인 뉘앙스 때문일 것이다. 그에 따라 각각 그 개념과 정의는 다르더라도 리더십의 여러 유형들은 구성원들의 직무태도, 직무성과 등 다수의 변수에 긍정적 영향을 준다는 많은 연구 증거들이 제시되었다. 그러나 최근 리더의 행동으로 인해 발생하는 부정적 영향, 즉 부정적 리더십에 대한 연구가 점차 증가하고 있는 추세다. Einarsen, Aasland, & Skogstad(2007)은 구성원 뿐 아니라 조직에도 손상을 가하는 리더의 부정적 행동을 파괴적 리더십 행동으로 정의하였다. 이후 다양한 형태의 부정적 리더십 유형이 제시되었는데, 독재적 리더십은 대표적인 부정적 리더십 유형 중 하나이다. 국외 연구들에 의하면, 독재적 리더십은 구성원의 의견을 무시하거나 의사결정과정에서 배제함으로써 구성원들에게 리더의 행위에 대한 부정적 감정을 유발시키고, 궁극적으로는 직무태도, 조직목표 달성에 대한 열정 등에 악영향을 초래하는 것으로 나타났다. 독재적 리더십의 부정적 영향을 밝히는 국외연구는 점차 증가하고 있으나, 국내의 연구 사례는 찾아보기 힘들다. 본 연구는 독재적 리더십이 LMX에 부정적 영향을 미치고, 이는 다시 부하의 주도적 행동을 떨어뜨린다는 것을 밝히고자 국내에서 수행된 실증연구다. 아울러 이 과정에서 구성원의 성장욕구 강도가 어떤 조절역할을 하는지를 살펴보았다. 공군 간부 272쌍을 대상으로 분석한 결과, 독재적 리더십은 LMX에 부적(-) 영향을 미치는 것으로 나타났고, 이로 인해 주도 적 행동이 저하되는 것으로 확인되었다. 또한 구성원의 성장욕구 강도가 높은 구성원일수록 독재적 리더 십이 LMX에 미치는 부정적 효과가 더 강하게 나타났다. 본 연구는 주로 서구에서 행해진 독재적 리더십의 부정적 효과가 동양 문화권에서도 유효하게 나타난다는 것을 밝혔다. 구체적으로, 리더의 부정적 행동이 상사와 부하 간 관계의 질을 떨어뜨리며, 이는 다시 조직을 위한 구성원의 주도적 행동에 부정적 영향을 미칠 수 있다는 사실을 알아냄으로써, 조직 내에서 리더의 역할, 행동이 얼마나 중요한 영향을 미칠 수 있는가를 잘 보여주고 있다. 아울러 무한 경쟁 속에서 갈수록 중요해지고 있는 구성원의 주도적 행동을 장려하려면 조직의 경영진은 현장에서 어떠한 리더십을 강조하고 예방해야 하는지에 대한 시사점을 제공해주고 있다.

Solid state grain growth (SSCG) is a method of growing large single crystals from seed single crystals by abnormal grain growth in a small-grained matrix. During grain growth, pores are often trapped in the matrix and remain in single crystals. Aerosol deposition (AD) is a method of manufacturing films with almost full density from nano grains by causing high energy collision between substrates and ceramic powders. AD and SSCG are used to grow single crystals with few pores. BaTiO3 films are coated on (100) SrTiO3 seeds by AD. To generate grain growth, BaTiO3 films are heated to 1,300 oC and held for 10 h, and entire films are grown as single crystals. The condition of grain growth driving force is ΔGmax < ΔGc ≤ ΔGseed. On the other hand, the condition of grain growth driving force in BaTiO3 AD films heat-treated at 1,100 and 1,200 oC is ΔGc < ΔGmax, and single crystals are not grown.

NKN [(Na,K)NbO3] is a candidate lead-free piezoelectric material to replace PZT [Pb(Zr,Ti)O3]. A single crystal has excellent piezoelectric-properties and its properties are dependent of the crystal orientation direction. However, it is hard to fabricate a single crystal with stoichiometrically stable composition due to volatilization of sodium during the growth process. To solve this problem, a solid solution composition is designed (Na,K)NbO3-Ba(Cu,Nb)O3 and solid state grain growth is studied for a sizable single crystal. Ceramic powders of (Na,K)NbO3-M(Cu,Nb)O3 (M = Ca, Sr, Ba) are synthesized and grain growth behavior is investigated for different temperatures and times. Average normal grain sizes of individual specimens, which are heat-treated at 1,125 oC for 10 h, are 6.9, 2.8, and 1.6 m for M = Ca, Sr, and Ba, respectively. Depending on M, the distortion of NKN structure can be altered. XRD results show that (NKN-CaCuN: shrunken orthorhombic; NKN-SrCuN: orthorhombic; NKN-BaCuN: cubic). For the sample heat-treated at 1,125 oC for 10 h, the maximum grain sizes of individual specimens are measured as 40, 5, and 4,000 m for M = Ca, Sr, and Ba, respectively. This abnormal grain size is related to the partial melting temperature (NKN-CaCuN: 960 oC; NKN-SrCuN: 971 oC; NKN-BaCuN: 945 oC).

Single crystals, which have complexed composition, are fabricated by solid state grain growth. However, it is hard to achieve stable properties in a single crystal due to trapped pores. Aerosol deposition (AD) is suitable for fabrication of single crystals with stable properties because this process can make a high density coating layer. Because of their unique features (nano sized grains, stress inner site), it is hard to fabricate single crystals, and so studies of grain growth behavior of AD film are essential. In this study, a BaTiO3 coating layer with ~ 9 μm thickness is fabricated using an aerosol deposition method on (100) and (110) cut SrTiO3 single crystal substrates, which are adopted as seeds for grain growth. Each specimen is heat-treated at various conditions (900, 1,100, and 1,300℃ for 5 h). BaTiO3 layer shows different growth behavior and X-ray diffraction depending on cutting direction of SrTiO3 seed. Rectangular pillars at SrTiO3 (100) and laminating thin plates at SrTiO3 (110), respectively, are observed.

The purpose of this study was to determine the effects of mixed or split-sex feeding on growth performance and behavior of Korean native chickens. Three variants of the sex ratio, FO (female only), MO (male only) and MI (mixed) were tested in Korean native chickens (Hanhyop 3) that were between the ages of 7 and 91 days. Body weight gain was the highest (p<0.05) in the MO treatment and the lowest (p<0.05) in the MI treatment. The feed intake (FI) of birds in the MO treatment was higher (p<0.05) than that of birds in the MI treatment during days 14-21, also MO treatment was higher (p<0.05) than that of birds in the MI treatment during days 21-28. However, the FI of birds in the MI group was higher (p<0.05) than that of birds in FO treatment during days 35-42. The behavioral frequency of walking, drinking, and aggressive pecking were not affected by sex ratio treatment. The behavioral frequency of feeding was higher in the FO treatment than that of birds in the other treatments. The comfort time of birds in the MI treatment was longer (p<0.05) than that of birds in the other treatments. The behavioral frequency of pecking was higher in the MO treatment than that of birds in the other treatments. The study suggests that when male and female Korean native chickens are reared together, sex ratio can influence growth performance and behavior frequency.

Pb(Zr,Ti)O3 (PZT) is used for the various piezoelectric devices owing to its high piezoelectric properties. However, lead (Pb), which is contained in PZT, causes various environment contaminations. (K,Na)NbO3 (NKN) is the most well-known candidate for a lead-free composition to replace PZT. A single crystal has excellent piezoelectric-properties and its properties can be changed by changing the orientation direction. It is hard to fabricate a NKN single crystal due to the sodium and potassium. Thus, (Na,K)NbO3-Ba(Cu,Nb)O3 (NKN-BCuN) is chosen to fabricate the single crystal with relative ease. NKNBCuN pellets consist of two parts, yellow single crystals and gray poly-crystals that contain copper. The area that has a large amount of copper particles may melt at low temperature but not the other areas. The liquid phase may be responsible for the abnormal grain growth in NKN-BCuN ceramics. The dielectric constant and tan δ are measured to be 684 and 0.036 at 1 kHz in NKN-BCuN, respectively. The coercive field and remnant polarization are 14 kV/cm and 20 μC/cm2.

Grain-growth behavior in the 95Na1/2Bi1/2TiO3-5BaTiO3 (mole fraction, NBT-5BT) system has been investigated with the addition of Na2CO3. When Na2CO3 is added to NBT-5BT, the growth rate is higher than desired and grains are already impinging each other during the initial stage of sintering. The grain size decreases as the sintering temperature increases. With the addition of Na2CO3, a liquid phase infiltrates the interfaces between grains during sintering. The interface structure can be changed to be more faceted and the interface migration rate can increase due to fast material transport through the liquid phase. As the sintering temperature increases, the impingement of abnormal grains increases because the number of abnormal grains increases. Therefore, the average grain size of abnormal grains can be decreased as the temperature increases. The phenomenon can provide evidence that grain coarsening in NBT-5BT with addition of Na2CO3 is governed by the growth of facet planes, which would occur via mixed control.

This study was performed to investigate how changing the period of light and dark influences the vegetative growth and the photosynthesis of Doritaenopsis Queen Beer ‘Mantefon’. Clones of Dtps. Queen Beer ‘Mantefon’ at 4-month-old stage were grown in a closed-plant factory system with four different light/dark cycles; 06/06 h, 08/08 h, 10/10 h, and 12/12 h. Temperature and relative humidity were set at 28oC and 80%, respectively, with a photosynthetic photon flux density of 160 ± 10 μmol·m-2·s-1. Repetitive measurements showed that the leaf length and the leaf width were the longest under 12/12 h closely followed by 10/10 h. The fresh weight and the dry weight of leaves and roots were the heaviest at 10/10 h treated samples. Different CO2 uptake patterns were observed from different light/dark cycles. Under 10/10 h and 12/12 h treatments, the CO2 uptake started at early dark period. When the light/dark cycles were shortened to 06/06 h and 08/08 h, the CO2 uptake started at the middle of dark period. Total CO2 uptake amounts were the highest under 12/12 h treatment followed by 10/10 h, 06/06 h, and 08/08 h treatments. Quantitative measurements showed that the vegetative growths under 10/10 h treatment were comparable with that of 12/12 h treatment. These studies indicated that manipulating light/dark can modify the photosynthesis patterns and vegetative growth of Dtps. Queen Beer ‘Mantefon’, resulting in the reduction of the production period.

본 연구는 grooming brush의 제공에 따른 한우 암소 육성우의 사양성적, 행동특성, 혈액 내 cortisol 및 혈액성상의 변화를 조사하였다. 6개월령의 암소 육성우(110.63±12.23kg) 32두를 32m2 우방에서 대조 구(non grooming brush), 처리구 1(Chevron angle type grooming brush, CHAT), 처리구 2(Straight type grooming brush, ST) 및 처리구 3(Chevron angle type and Straight type grooming brush, CHAST)으로 처리당 4두씩, 4처리 2반복으로 완전임의 배치하여, 2주간 예비시험 후 8개월간 본 시험 을 실시하였다. 시험결과 grooming brush 제공에 따른 사양성적으로 종료 시 체중과 일당증체량에서 는 대조구 대비 처리구에서 유의적(p<0.05)으로 증가하였고, 사료요구율에서는 대조구에서 가장 낮은 사양성적을 보였다(p<0.05). 행동특성 중 횡화 및 걷기시간은 대조구 대비 grooming brush를 제공한 모든 처리구에 유의적으로 높게 나타났다(p<0.05). 음수행동의 빈도는 처리구 3에서 유의적(p<0.05)으 로 증가하였다. 또한, 몸단장행동인 자기몸 핥기, brushing 행동과 투쟁행동은 대조구에서 다른 처리구 에 비해 유의적으로 증가하였다(p<0.05). 혈액성상에서 헤모글로빈수치는 처리구에서 유의적(p<0.05) 으로 높았고, 스트레스 호르몬인 cortisol 농도는 대조구에서 유의적(p<0.05)으로 높은 수치를 보였다. 따라서, grooming brush 제공에 따른 한우 육성 성적, 행동특성 그리고 혈액 내 cortisol의 변화는 집 단생활을 하는 소의 사회적인 행동에 긍정적인 영향을 미치는 것으로 볼 수 있으며, 스트레스 저감으로 인해 건강한 발육에 기여하는 것으로 나타났다.

In experiment dealt with 240 Hanwoo (172 steers and 68 heifers) among the 456 cattle during growing and fattening period were used from 2004 to 2015. Growth period was divided into 6, 12, 18, and 24 months for steers and 6, 12, 18, and 43 months for heifers. The results showed that lying down, feeding, and drinking behavior increased according to the growth. In contrary, the time of locomotion behavior including standing and walking behavior were reduced. Aggressive behavior was observed to be mostly generated in the first 6-months. Thus the results showed that different growth period of Hanwoo steers can be used as management systems for breeding and disease management. It conclude that providing a comfortable living space is a useful management systems suppress stress to the minimum extent without giving unnecessary stress to the animals.

Fatigue crack growth rate tests were conducted as a function of temperature, dissolved hydrogen (DH) level, and frequency in a simulated PWR environment. Fatigue crack growth rates increased slightly with increasing temperature in air. However, the fatigue crack growth rate did not change with increasing temperature in PWR water conditions. The DH levels did not affect the measured crack growth rate under the given test conditions. At 316 oC, oxides were observed on the fatigue crack surface, where the size of the oxide particles was about 0.2 μm at 5 ppb. Fatigue crack growth rate increased slightly with decreasing frequency within the frequency range of 0.1 Hz and 10 Hz in PWR water conditions; however, crack growth rate increased considerably at 0.01 Hz. The decrease of the fatigue crack growth rate in PWR water condition is attributed to crack closure resulting from the formation of oxides near the crack tips at a rather fast loading frequency of 10 Hz.

In this study, modified catalytic chemical vapor deposition (CCVD) method was applied to control the CNTs (carbon nanotubes) growth. Since titanium (Ti) substrate and iron (Fe) catalysts react one another and form a new phase (Fe2TiO5) above 700℃, the decrease of CNT yield above 800℃ where methane gas decomposes is inevitable under common CCVD method. Therefore, we synthesized CNTs on the Ti substrate by dividing the tube furnace into two sections (left and right) and heating them to different temperatures each. The reactant gas flew through from the end of the right tube furnace while the Ti substrate was placed in the center of the left tube furnace. When the CNT growth temperature was set 700/950℃ (left/right), CNTs with high yield were observed. Also, by examining the micro-structure of CNTs of 700/950℃, it was confirmed that CNTs show the bamboo-like structure.

Sheet aluminum alloys have been used in manufacturing of machine structures. In fatigue crack propagation behavior of thin sheet aluminum alloys, it is important that fatigue crack growth rate is affected by crack closure phenomenon. In this work, we analyzed the characteristics of fatigue crack propagation behavior in experiment of constant stress condition for thin sheet Al 2024-T3 alloys, and identified the retardation behavior of crack growth by comparing experimental results of thin and thick plate specimen. We attempt to operate the fatigue life estimating process using the fatigue related material constants from referred fatigue crack propagation analysis. And we analyzed the experimental and prediction results of fatigue life of thin sheet aluminum alloy in order to identify the relation between retardation behavior of fatigue crack growth and crack closure phenomenon.

Recently, nanotubes have considerably researched because of their novel application about photocatalysis, dye-sensitized solar cells (DSSCs), lithium ion battery, etc. In this work, self-standing nanotube arrays were fabricated by anodic oxidation method using pure Ti foil as a working electrode in ethylene glycole with 0.3M + . Growth behavior of nanotube arrays was compared according to temperature, voltage and time. The morphology, structure and crystalline of anodized nanotube arrays were observed by FE-SEM (field emission scanning electron microscope) and XRD (X-ray diffraction).

Growth behavior of InGaN/GaN self-assembled quantum dots (QDs) was investigated with respect to different growth parameters in low pressure metalorganic chemical vapor deposition. Locally formed examples of three dimensional InGaN islands were confirmed from the surface observation image with increasing indium source ratio and growth time. The InGaN/GaN QDs were formed in Stranski-Krastanow (SK) growth mode by the continuous supply of metalorganic (MO) sources, whereas they were formed in the Volmer-Weber (V-W) growth mode by the periodic interruption of the MO sources. High density InGaN QDs with 1~2nm height and 40~50nm diameter were formed by the S-K growth mode. Dome shape InGaN dots with 200~400nm diameter were formed by the V-W growth mode. InN content in InGaN QDs was estimated to be reduced with the increase of growth temperature. A strong peak between 420-460 nm (2.96-2.70 eV) was observed for the InGaN QDs grown by S-K growth mode in photoluminescence spectrum together with the GaN buffer layer peak at 362.2 nm (3.41 eV).